gem5/src/sim/process.cc
Brandon Potter d3d983caf9 syscall_emul: [patch 10/22] refactor fdentry and add fdarray class
Several large changes happen in this patch.

The FDEntry class is rewritten so that file descriptors now correspond to
types: 'File' which is normal file-backed file with the file open on the
host machine, 'Pipe' which is a pipe that has been opened on the host machine,
and 'Device' which does not have an open file on the host yet acts as a pseudo
device with which to issue ioctls. Other types which might be added in the
future are directory entries and sockets (off the top of my head).

The FDArray class was create to hold most of the file descriptor handling
that was stuffed into the Process class. It uses shared pointers and
the std::array type to hold the FDEntries mentioned above.

The changes to these two classes needed to be propagated out to the rest
of the code so there were quite a few changes for that. Also, comments were
added where I thought they were needed to help others and extend our
DOxygen coverage.
2016-11-09 14:27:42 -06:00

515 lines
16 KiB
C++

/*
* Copyright (c) 2014-2016 Advanced Micro Devices, Inc.
* Copyright (c) 2012 ARM Limited
* All rights reserved
*
* The license below extends only to copyright in the software and shall
* not be construed as granting a license to any other intellectual
* property including but not limited to intellectual property relating
* to a hardware implementation of the functionality of the software
* licensed hereunder. You may use the software subject to the license
* terms below provided that you ensure that this notice is replicated
* unmodified and in its entirety in all distributions of the software,
* modified or unmodified, in source code or in binary form.
*
* Copyright (c) 2001-2005 The Regents of The University of Michigan
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met: redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer;
* redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution;
* neither the name of the copyright holders nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* Authors: Nathan Binkert
* Steve Reinhardt
* Ali Saidi
* Brandon Potter
*/
#include "sim/process.hh"
#include <fcntl.h>
#include <unistd.h>
#include <array>
#include <map>
#include <string>
#include <vector>
#include "base/intmath.hh"
#include "base/loader/object_file.hh"
#include "base/loader/symtab.hh"
#include "base/statistics.hh"
#include "config/the_isa.hh"
#include "cpu/thread_context.hh"
#include "mem/page_table.hh"
#include "mem/se_translating_port_proxy.hh"
#include "params/Process.hh"
#include "sim/emul_driver.hh"
#include "sim/fd_array.hh"
#include "sim/fd_entry.hh"
#include "sim/syscall_desc.hh"
#include "sim/system.hh"
#if THE_ISA == ALPHA_ISA
#include "arch/alpha/linux/process.hh"
#elif THE_ISA == SPARC_ISA
#include "arch/sparc/linux/process.hh"
#include "arch/sparc/solaris/process.hh"
#elif THE_ISA == MIPS_ISA
#include "arch/mips/linux/process.hh"
#elif THE_ISA == ARM_ISA
#include "arch/arm/linux/process.hh"
#include "arch/arm/freebsd/process.hh"
#elif THE_ISA == X86_ISA
#include "arch/x86/linux/process.hh"
#elif THE_ISA == POWER_ISA
#include "arch/power/linux/process.hh"
#elif THE_ISA == RISCV_ISA
#include "arch/riscv/linux/process.hh"
#else
#error "THE_ISA not set"
#endif
using namespace std;
using namespace TheISA;
Process::Process(ProcessParams * params, ObjectFile * obj_file)
: SimObject(params), system(params->system),
brk_point(0), stack_base(0), stack_size(0), stack_min(0),
max_stack_size(params->max_stack_size),
next_thread_stack_base(0),
useArchPT(params->useArchPT),
kvmInSE(params->kvmInSE),
pTable(useArchPT ?
static_cast<PageTableBase *>(new ArchPageTable(name(), params->pid,
system)) :
static_cast<PageTableBase *>(new FuncPageTable(name(), params->pid))),
initVirtMem(system->getSystemPort(), this,
SETranslatingPortProxy::Always),
objFile(obj_file),
argv(params->cmd), envp(params->env), cwd(params->cwd),
executable(params->executable),
_uid(params->uid), _euid(params->euid),
_gid(params->gid), _egid(params->egid),
_pid(params->pid), _ppid(params->ppid),
drivers(params->drivers),
fds(make_shared<FDArray>(params->input, params->output, params->errout))
{
mmap_end = 0;
// load up symbols, if any... these may be used for debugging or
// profiling.
if (!debugSymbolTable) {
debugSymbolTable = new SymbolTable();
if (!objFile->loadGlobalSymbols(debugSymbolTable) ||
!objFile->loadLocalSymbols(debugSymbolTable) ||
!objFile->loadWeakSymbols(debugSymbolTable)) {
// didn't load any symbols
delete debugSymbolTable;
debugSymbolTable = NULL;
}
}
}
void
Process::regStats()
{
SimObject::regStats();
using namespace Stats;
num_syscalls
.name(name() + ".num_syscalls")
.desc("Number of system calls")
;
}
ThreadContext *
Process::findFreeContext()
{
for (int id : contextIds) {
ThreadContext *tc = system->getThreadContext(id);
if (tc->status() == ThreadContext::Halted)
return tc;
}
return NULL;
}
void
Process::initState()
{
if (contextIds.empty())
fatal("Process %s is not associated with any HW contexts!\n", name());
// first thread context for this process... initialize & enable
ThreadContext *tc = system->getThreadContext(contextIds[0]);
// mark this context as active so it will start ticking.
tc->activate();
pTable->initState(tc);
}
DrainState
Process::drain()
{
fds->updateFileOffsets();
return DrainState::Drained;
}
void
Process::allocateMem(Addr vaddr, int64_t size, bool clobber)
{
int npages = divCeil(size, (int64_t)PageBytes);
Addr paddr = system->allocPhysPages(npages);
pTable->map(vaddr, paddr, size,
clobber ? PageTableBase::Clobber : PageTableBase::Zero);
}
bool
Process::fixupStackFault(Addr vaddr)
{
// Check if this is already on the stack and there's just no page there
// yet.
if (vaddr >= stack_min && vaddr < stack_base) {
allocateMem(roundDown(vaddr, PageBytes), PageBytes);
return true;
}
// We've accessed the next page of the stack, so extend it to include
// this address.
if (vaddr < stack_min && vaddr >= stack_base - max_stack_size) {
while (vaddr < stack_min) {
stack_min -= TheISA::PageBytes;
if (stack_base - stack_min > max_stack_size)
fatal("Maximum stack size exceeded\n");
allocateMem(stack_min, TheISA::PageBytes);
inform("Increasing stack size by one page.");
};
return true;
}
return false;
}
void
Process::serialize(CheckpointOut &cp) const
{
SERIALIZE_SCALAR(brk_point);
SERIALIZE_SCALAR(stack_base);
SERIALIZE_SCALAR(stack_size);
SERIALIZE_SCALAR(stack_min);
SERIALIZE_SCALAR(next_thread_stack_base);
SERIALIZE_SCALAR(mmap_end);
pTable->serialize(cp);
/**
* Checkpoints for file descriptors currently do not work. Need to
* come back and fix them at a later date.
*/
warn("Checkpoints for file descriptors currently do not work.");
#if 0
for (int x = 0; x < fds->getSize(); x++)
(*fds)[x].serializeSection(cp, csprintf("FDEntry%d", x));
#endif
}
void
Process::unserialize(CheckpointIn &cp)
{
UNSERIALIZE_SCALAR(brk_point);
UNSERIALIZE_SCALAR(stack_base);
UNSERIALIZE_SCALAR(stack_size);
UNSERIALIZE_SCALAR(stack_min);
UNSERIALIZE_SCALAR(next_thread_stack_base);
UNSERIALIZE_SCALAR(mmap_end);
pTable->unserialize(cp);
/**
* Checkpoints for file descriptors currently do not work. Need to
* come back and fix them at a later date.
*/
warn("Checkpoints for file descriptors currently do not work.");
#if 0
for (int x = 0; x < fds->getSize(); x++)
(*fds)[x]->unserializeSection(cp, csprintf("FDEntry%d", x));
fds->restoreFileOffsets();
#endif
// The above returns a bool so that you could do something if you don't
// find the param in the checkpoint if you wanted to, like set a default
// but in this case we'll just stick with the instantiated value if not
// found.
}
bool
Process::map(Addr vaddr, Addr paddr, int size, bool cacheable)
{
pTable->map(vaddr, paddr, size,
cacheable ? PageTableBase::Zero : PageTableBase::Uncacheable);
return true;
}
void
Process::syscall(int64_t callnum, ThreadContext *tc)
{
num_syscalls++;
SyscallDesc *desc = getDesc(callnum);
if (desc == NULL)
fatal("Syscall %d out of range", callnum);
desc->doSyscall(callnum, this, tc);
}
IntReg
Process::getSyscallArg(ThreadContext *tc, int &i, int width)
{
return getSyscallArg(tc, i);
}
EmulatedDriver *
Process::findDriver(std::string filename)
{
for (EmulatedDriver *d : drivers) {
if (d->match(filename))
return d;
}
return NULL;
}
void
Process::updateBias()
{
ObjectFile *interp = objFile->getInterpreter();
if (!interp || !interp->relocatable())
return;
// Determine how large the interpreters footprint will be in the process
// address space.
Addr interp_mapsize = roundUp(interp->mapSize(), TheISA::PageBytes);
// We are allocating the memory area; set the bias to the lowest address
// in the allocated memory region.
Addr ld_bias = mmapGrowsDown() ? mmap_end - interp_mapsize : mmap_end;
// Adjust the process mmap area to give the interpreter room; the real
// execve system call would just invoke the kernel's internal mmap
// functions to make these adjustments.
mmap_end = mmapGrowsDown() ? ld_bias : mmap_end + interp_mapsize;
interp->updateBias(ld_bias);
}
ObjectFile *
Process::getInterpreter()
{
return objFile->getInterpreter();
}
Addr
Process::getBias()
{
ObjectFile *interp = getInterpreter();
return interp ? interp->bias() : objFile->bias();
}
Addr
Process::getStartPC()
{
ObjectFile *interp = getInterpreter();
return interp ? interp->entryPoint() : objFile->entryPoint();
}
Process *
ProcessParams::create()
{
Process *process = NULL;
// If not specified, set the executable parameter equal to the
// simulated system's zeroth command line parameter
if (executable == "") {
executable = cmd[0];
}
ObjectFile *obj_file = createObjectFile(executable);
if (obj_file == NULL) {
fatal("Can't load object file %s", executable);
}
#if THE_ISA == ALPHA_ISA
if (obj_file->getArch() != ObjectFile::Alpha)
fatal("Object file architecture does not match compiled ISA (Alpha).");
switch (obj_file->getOpSys()) {
case ObjectFile::UnknownOpSys:
warn("Unknown operating system; assuming Linux.");
// fall through
case ObjectFile::Linux:
process = new AlphaLinuxProcess(this, obj_file);
break;
default:
fatal("Unknown/unsupported operating system.");
}
#elif THE_ISA == SPARC_ISA
if (obj_file->getArch() != ObjectFile::SPARC64 &&
obj_file->getArch() != ObjectFile::SPARC32)
fatal("Object file architecture does not match compiled ISA (SPARC).");
switch (obj_file->getOpSys()) {
case ObjectFile::UnknownOpSys:
warn("Unknown operating system; assuming Linux.");
// fall through
case ObjectFile::Linux:
if (obj_file->getArch() == ObjectFile::SPARC64) {
process = new Sparc64LinuxProcess(this, obj_file);
} else {
process = new Sparc32LinuxProcess(this, obj_file);
}
break;
case ObjectFile::Solaris:
process = new SparcSolarisProcess(this, obj_file);
break;
default:
fatal("Unknown/unsupported operating system.");
}
#elif THE_ISA == X86_ISA
if (obj_file->getArch() != ObjectFile::X86_64 &&
obj_file->getArch() != ObjectFile::I386)
fatal("Object file architecture does not match compiled ISA (x86).");
switch (obj_file->getOpSys()) {
case ObjectFile::UnknownOpSys:
warn("Unknown operating system; assuming Linux.");
// fall through
case ObjectFile::Linux:
if (obj_file->getArch() == ObjectFile::X86_64) {
process = new X86_64LinuxProcess(this, obj_file);
} else {
process = new I386LinuxProcess(this, obj_file);
}
break;
default:
fatal("Unknown/unsupported operating system.");
}
#elif THE_ISA == MIPS_ISA
if (obj_file->getArch() != ObjectFile::Mips)
fatal("Object file architecture does not match compiled ISA (MIPS).");
switch (obj_file->getOpSys()) {
case ObjectFile::UnknownOpSys:
warn("Unknown operating system; assuming Linux.");
// fall through
case ObjectFile::Linux:
process = new MipsLinuxProcess(this, obj_file);
break;
default:
fatal("Unknown/unsupported operating system.");
}
#elif THE_ISA == ARM_ISA
ObjectFile::Arch arch = obj_file->getArch();
if (arch != ObjectFile::Arm && arch != ObjectFile::Thumb &&
arch != ObjectFile::Arm64)
fatal("Object file architecture does not match compiled ISA (ARM).");
switch (obj_file->getOpSys()) {
case ObjectFile::UnknownOpSys:
warn("Unknown operating system; assuming Linux.");
// fall through
case ObjectFile::Linux:
if (arch == ObjectFile::Arm64) {
process = new ArmLinuxProcess64(this, obj_file,
obj_file->getArch());
} else {
process = new ArmLinuxProcess32(this, obj_file,
obj_file->getArch());
}
break;
case ObjectFile::FreeBSD:
if (arch == ObjectFile::Arm64) {
process = new ArmFreebsdProcess64(this, obj_file,
obj_file->getArch());
} else {
process = new ArmFreebsdProcess32(this, obj_file,
obj_file->getArch());
}
break;
case ObjectFile::LinuxArmOABI:
fatal("M5 does not support ARM OABI binaries. Please recompile with an"
" EABI compiler.");
default:
fatal("Unknown/unsupported operating system.");
}
#elif THE_ISA == POWER_ISA
if (obj_file->getArch() != ObjectFile::Power)
fatal("Object file architecture does not match compiled ISA (Power).");
switch (obj_file->getOpSys()) {
case ObjectFile::UnknownOpSys:
warn("Unknown operating system; assuming Linux.");
// fall through
case ObjectFile::Linux:
process = new PowerLinuxProcess(this, obj_file);
break;
default:
fatal("Unknown/unsupported operating system.");
}
#elif THE_ISA == RISCV_ISA
if (obj_file->getArch() != ObjectFile::Riscv)
fatal("Object file architecture does not match compiled ISA (RISCV).");
switch (obj_file->getOpSys()) {
case ObjectFile::UnknownOpSys:
warn("Unknown operating system; assuming Linux.");
// fall through
case ObjectFile::Linux:
process = new RiscvLinuxProcess(this, obj_file);
break;
default:
fatal("Unknown/unsupported operating system.");
}
#else
#error "THE_ISA not set"
#endif
if (process == NULL)
fatal("Unknown error creating process object.");
return process;
}
std::string
Process::fullPath(const std::string &file_name)
{
if (file_name[0] == '/' || cwd.empty())
return file_name;
std::string full = cwd;
if (cwd[cwd.size() - 1] != '/')
full += '/';
return full + file_name;
}