src/sim/process.cc - arm/gem5 - Git at Google

 /*
  * Copyright (c) 2014 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
  */

 #include <fcntl.h>
 #include <unistd.h>

 #include <cstdio>
 #include <string>

 #include "base/loader/object_file.hh"
 #include "base/loader/symtab.hh"
 #include "base/intmath.hh"
 #include "base/statistics.hh"
 #include "config/the_isa.hh"
 #include "cpu/thread_context.hh"
 #include "mem/page_table.hh"
 #include "mem/multi_level_page_table.hh"
 #include "mem/se_translating_port_proxy.hh"
 #include "params/LiveProcess.hh"
 #include "params/Process.hh"
 #include "sim/debug.hh"
 #include "sim/process.hh"
 #include "sim/process_impl.hh"
 #include "sim/stats.hh"
 #include "sim/syscall_emul.hh"
 #include "sim/system.hh"

 #if THE_ISA == ALPHA_ISA
 #include "arch/alpha/linux/process.hh"
 #include "arch/alpha/tru64/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"
 #elif THE_ISA == X86_ISA
 #include "arch/x86/linux/process.hh"
 #elif THE_ISA == POWER_ISA
 #include "arch/power/linux/process.hh"
 #else
 #error "THE_ISA not set"
 #endif


 using namespace std;
 using namespace TheISA;

 // current number of allocated processes
 int num_processes = 0;

 template<class IntType>
 AuxVector<IntType>::AuxVector(IntType type, IntType val)
 {
     a_type = TheISA::htog(type);
     a_val = TheISA::htog(val);
 }

 template struct AuxVector<uint32_t>;
 template struct AuxVector<uint64_t>;

 Process::Process(ProcessParams * params)
     : SimObject(params), system(params->system),
       max_stack_size(params->max_stack_size),
       M5_pid(system->allocatePID()),
       useArchPT(params->useArchPT),
       pTable(useArchPT ?
         static_cast<PageTableBase *>(new ArchPageTable(name(), M5_pid, system)) :
         static_cast<PageTableBase *>(new FuncPageTable(name(), M5_pid)) ),
       initVirtMem(system->getSystemPort(), this,
                   SETranslatingPortProxy::Always)
 {
     string in = params->input;
     string out = params->output;
     string err = params->errout;

     // initialize file descriptors to default: same as simulator
     int stdin_fd, stdout_fd, stderr_fd;

     if (in == "stdin" || in == "cin")
         stdin_fd = STDIN_FILENO;
     else if (in == "None")
         stdin_fd = -1;
     else
         stdin_fd = Process::openInputFile(in);

     if (out == "stdout" || out == "cout")
         stdout_fd = STDOUT_FILENO;
     else if (out == "stderr" || out == "cerr")
         stdout_fd = STDERR_FILENO;
     else if (out == "None")
         stdout_fd = -1;
     else
         stdout_fd = Process::openOutputFile(out);

     if (err == "stdout" || err == "cout")
         stderr_fd = STDOUT_FILENO;
     else if (err == "stderr" || err == "cerr")
         stderr_fd = STDERR_FILENO;
     else if (err == "None")
         stderr_fd = -1;
     else if (err == out)
         stderr_fd = stdout_fd;
     else
         stderr_fd = Process::openOutputFile(err);

     // initialize first 3 fds (stdin, stdout, stderr)
     Process::FdMap *fdo = &fd_map[STDIN_FILENO];
     fdo->fd = stdin_fd;
     fdo->filename = in;
     fdo->flags = O_RDONLY;
     fdo->mode = -1;
     fdo->fileOffset = 0;

     fdo =  &fd_map[STDOUT_FILENO];
     fdo->fd = stdout_fd;
     fdo->filename = out;
     fdo->flags =  O_WRONLY | O_CREAT | O_TRUNC;
     fdo->mode = 0774;
     fdo->fileOffset = 0;

     fdo = &fd_map[STDERR_FILENO];
     fdo->fd = stderr_fd;
     fdo->filename = err;
     fdo->flags = O_WRONLY;
     fdo->mode = -1;
     fdo->fileOffset = 0;


     // mark remaining fds as free
     for (int i = 3; i <= MAX_FD; ++i) {
         fdo = &fd_map[i];
         fdo->fd = -1;
     }

     mmap_start = mmap_end = 0;
     nxm_start = nxm_end = 0;
     // other parameters will be initialized when the program is loaded
 }


 void
 Process::regStats()
 {
     using namespace Stats;

     num_syscalls
         .name(name() + ".num_syscalls")
         .desc("Number of system calls")
         ;
 }

 //
 // static helper functions
 //
 int
 Process::openInputFile(const string &filename)
 {
     int fd = open(filename.c_str(), O_RDONLY);

     if (fd == -1) {
         perror(NULL);
         cerr << "unable to open \"" << filename << "\" for reading\n";
         fatal("can't open input file");
     }

     return fd;
 }


 int
 Process::openOutputFile(const string &filename)
 {
     int fd = open(filename.c_str(), O_WRONLY | O_CREAT | O_TRUNC, 0664);

     if (fd == -1) {
         perror(NULL);
         cerr << "unable to open \"" << filename << "\" for writing\n";
         fatal("can't open output file");
     }

     return fd;
 }

 ThreadContext *
 Process::findFreeContext()
 {
     int size = contextIds.size();
     ThreadContext *tc;
     for (int i = 0; i < size; ++i) {
         tc = system->getThreadContext(contextIds[i]);
         if (tc->status() == ThreadContext::Halted) {
             // inactive context, free to use
             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);
 }

 // map simulator fd sim_fd to target fd tgt_fd
 void
 Process::dup_fd(int sim_fd, int tgt_fd)
 {
     if (tgt_fd < 0 || tgt_fd > MAX_FD)
         panic("Process::dup_fd tried to dup past MAX_FD (%d)", tgt_fd);

     Process::FdMap *fdo = &fd_map[tgt_fd];
     fdo->fd = sim_fd;
 }


 // generate new target fd for sim_fd
 int
 Process::alloc_fd(int sim_fd, string filename, int flags, int mode, bool pipe)
 {
     // in case open() returns an error, don't allocate a new fd
     if (sim_fd == -1)
         return -1;

     // find first free target fd
     for (int free_fd = 0; free_fd <= MAX_FD; ++free_fd) {
         Process::FdMap *fdo = &fd_map[free_fd];
         if (fdo->fd == -1) {
             fdo->fd = sim_fd;
             fdo->filename = filename;
             fdo->mode = mode;
             fdo->fileOffset = 0;
             fdo->flags = flags;
             fdo->isPipe = pipe;
             fdo->readPipeSource = 0;
             return free_fd;
         }
     }

     panic("Process::alloc_fd: out of file descriptors!");
 }


 // free target fd (e.g., after close)
 void
 Process::free_fd(int tgt_fd)
 {
     Process::FdMap *fdo = &fd_map[tgt_fd];
     if (fdo->fd == -1)
         warn("Process::free_fd: request to free unused fd %d", tgt_fd);

     fdo->fd = -1;
     fdo->filename = "NULL";
     fdo->mode = 0;
     fdo->fileOffset = 0;
     fdo->flags = 0;
     fdo->isPipe = false;
     fdo->readPipeSource = 0;
 }


 // look up simulator fd for given target fd
 int
 Process::sim_fd(int tgt_fd)
 {
     if (tgt_fd < 0 || tgt_fd > MAX_FD)
         return -1;

     return fd_map[tgt_fd].fd;
 }

 Process::FdMap *
 Process::sim_fd_obj(int tgt_fd)
 {
     if (tgt_fd < 0 || tgt_fd > MAX_FD)
         return NULL;

     return &fd_map[tgt_fd];
 }

 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);
 }

 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;
 }

 // find all offsets for currently open files and save them
 void
 Process::fix_file_offsets()
 {
     Process::FdMap *fdo_stdin = &fd_map[STDIN_FILENO];
     Process::FdMap *fdo_stdout = &fd_map[STDOUT_FILENO];
     Process::FdMap *fdo_stderr = &fd_map[STDERR_FILENO];
     string in = fdo_stdin->filename;
     string out = fdo_stdout->filename;
     string err = fdo_stderr->filename;

     // initialize file descriptors to default: same as simulator
     int stdin_fd, stdout_fd, stderr_fd;

     if (in == "stdin" || in == "cin")
         stdin_fd = STDIN_FILENO;
     else if (in == "None")
         stdin_fd = -1;
     else {
         // open standard in and seek to the right location
         stdin_fd = Process::openInputFile(in);
         if (lseek(stdin_fd, fdo_stdin->fileOffset, SEEK_SET) < 0)
             panic("Unable to seek to correct location in file: %s", in);
     }

     if (out == "stdout" || out == "cout")
         stdout_fd = STDOUT_FILENO;
     else if (out == "stderr" || out == "cerr")
         stdout_fd = STDERR_FILENO;
     else if (out == "None")
         stdout_fd = -1;
     else {
         stdout_fd = Process::openOutputFile(out);
         if (lseek(stdout_fd, fdo_stdout->fileOffset, SEEK_SET) < 0)
             panic("Unable to seek to correct location in file: %s", out);
     }

     if (err == "stdout" || err == "cout")
         stderr_fd = STDOUT_FILENO;
     else if (err == "stderr" || err == "cerr")
         stderr_fd = STDERR_FILENO;
     else if (err == "None")
         stderr_fd = -1;
     else if (err == out)
         stderr_fd = stdout_fd;
     else {
         stderr_fd = Process::openOutputFile(err);
         if (lseek(stderr_fd, fdo_stderr->fileOffset, SEEK_SET) < 0)
             panic("Unable to seek to correct location in file: %s", err);
     }

     fdo_stdin->fd = stdin_fd;
     fdo_stdout->fd = stdout_fd;
     fdo_stderr->fd = stderr_fd;


     for (int free_fd = 3; free_fd <= MAX_FD; ++free_fd) {
         Process::FdMap *fdo = &fd_map[free_fd];
         if (fdo->fd != -1) {
             if (fdo->isPipe){
                 if (fdo->filename == "PIPE-WRITE")
                     continue;
                 else {
                     assert (fdo->filename == "PIPE-READ");
                     //create a new pipe
                     int fds[2];
                     int pipe_retval = pipe(fds);

                     if (pipe_retval < 0) {
                         // error
                         panic("Unable to create new pipe.");
                     }
                     fdo->fd = fds[0]; //set read pipe
                     Process::FdMap *fdo_write = &fd_map[fdo->readPipeSource];
                     if (fdo_write->filename != "PIPE-WRITE")
                         panic ("Couldn't find write end of the pipe");

                     fdo_write->fd = fds[1];//set write pipe
                }
             } else {
                 //Open file
                 int fd = open(fdo->filename.c_str(), fdo->flags, fdo->mode);

                 if (fd == -1)
                     panic("Unable to open file: %s", fdo->filename);
                 fdo->fd = fd;

                 //Seek to correct location before checkpoint
                 if (lseek(fd,fdo->fileOffset, SEEK_SET) < 0)
                     panic("Unable to seek to correct location in file: %s",
                           fdo->filename);
             }
         }
     }
 }

 void
 Process::find_file_offsets()
 {
     for (int free_fd = 0; free_fd <= MAX_FD; ++free_fd) {
         Process::FdMap *fdo = &fd_map[free_fd];
         if (fdo->fd != -1) {
             fdo->fileOffset = lseek(fdo->fd, 0, SEEK_CUR);
         } else {
                 fdo->filename = "NULL";
                 fdo->fileOffset = 0;
         }
     }
 }

 void
 Process::setReadPipeSource(int read_pipe_fd, int source_fd)
 {
     Process::FdMap *fdo = &fd_map[read_pipe_fd];
     fdo->readPipeSource = source_fd;
 }

 void
 Process::FdMap::serialize(std::ostream &os)
 {
     SERIALIZE_SCALAR(fd);
     SERIALIZE_SCALAR(isPipe);
     SERIALIZE_SCALAR(filename);
     SERIALIZE_SCALAR(flags);
     SERIALIZE_SCALAR(readPipeSource);
     SERIALIZE_SCALAR(fileOffset);
 }

 void
 Process::FdMap::unserialize(Checkpoint *cp, const std::string &section)
 {
     UNSERIALIZE_SCALAR(fd);
     UNSERIALIZE_SCALAR(isPipe);
     UNSERIALIZE_SCALAR(filename);
     UNSERIALIZE_SCALAR(flags);
     UNSERIALIZE_SCALAR(readPipeSource);
     UNSERIALIZE_SCALAR(fileOffset);
 }

 void
 Process::serialize(std::ostream &os)
 {
     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_start);
     SERIALIZE_SCALAR(mmap_end);
     SERIALIZE_SCALAR(nxm_start);
     SERIALIZE_SCALAR(nxm_end);
     find_file_offsets();
     pTable->serialize(os);
     for (int x = 0; x <= MAX_FD; x++) {
         nameOut(os, csprintf("%s.FdMap%d", name(), x));
         fd_map[x].serialize(os);
     }
     SERIALIZE_SCALAR(M5_pid);

 }

 void
 Process::unserialize(Checkpoint *cp, const std::string &section)
 {
     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_start);
     UNSERIALIZE_SCALAR(mmap_end);
     UNSERIALIZE_SCALAR(nxm_start);
     UNSERIALIZE_SCALAR(nxm_end);
     pTable->unserialize(cp, section);
     for (int x = 0; x <= MAX_FD; x++) {
         fd_map[x].unserialize(cp, csprintf("%s.FdMap%d", section, x));
     }
     fix_file_offsets();
     UNSERIALIZE_OPT_SCALAR(M5_pid);
     // 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 instantianted value if not
     // found.
 }


 bool
 Process::map(Addr vaddr, Addr paddr, int size)
 {
     pTable->map(vaddr, paddr, size);
     return true;
 }


 ////////////////////////////////////////////////////////////////////////
 //
 // LiveProcess member definitions
 //
 ////////////////////////////////////////////////////////////////////////


 LiveProcess::LiveProcess(LiveProcessParams * params, ObjectFile *_objFile)
     : Process(params), objFile(_objFile),
       argv(params->cmd), envp(params->env), cwd(params->cwd)
 {
     __uid = params->uid;
     __euid = params->euid;
     __gid = params->gid;
     __egid = params->egid;
     __pid = params->pid;
     __ppid = params->ppid;

     // 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
 LiveProcess::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
 LiveProcess::getSyscallArg(ThreadContext *tc, int &i, int width)
 {
     return getSyscallArg(tc, i);
 }

 LiveProcess *
 LiveProcess::create(LiveProcessParams * params)
 {
     LiveProcess *process = NULL;

     string executable =
         params->executable == "" ? params->cmd[0] : params->executable;
     ObjectFile *objFile = createObjectFile(executable);
     if (objFile == NULL) {
         fatal("Can't load object file %s", executable);
     }

     if (objFile->isDynamic())
        fatal("Object file is a dynamic executable however only static "
              "executables are supported!\n       Please recompile your "
              "executable as a static binary and try again.\n");

 #if THE_ISA == ALPHA_ISA
     if (objFile->getArch() != ObjectFile::Alpha)
         fatal("Object file architecture does not match compiled ISA (Alpha).");

     switch (objFile->getOpSys()) {
       case ObjectFile::Tru64:
         process = new AlphaTru64Process(params, objFile);
         break;

       case ObjectFile::UnknownOpSys:
         warn("Unknown operating system; assuming Linux.");
         // fall through
       case ObjectFile::Linux:
         process = new AlphaLinuxProcess(params, objFile);
         break;

       default:
         fatal("Unknown/unsupported operating system.");
     }
 #elif THE_ISA == SPARC_ISA
     if (objFile->getArch() != ObjectFile::SPARC64 &&
         objFile->getArch() != ObjectFile::SPARC32)
         fatal("Object file architecture does not match compiled ISA (SPARC).");
     switch (objFile->getOpSys()) {
       case ObjectFile::UnknownOpSys:
         warn("Unknown operating system; assuming Linux.");
         // fall through
       case ObjectFile::Linux:
         if (objFile->getArch() == ObjectFile::SPARC64) {
             process = new Sparc64LinuxProcess(params, objFile);
         } else {
             process = new Sparc32LinuxProcess(params, objFile);
         }
         break;


       case ObjectFile::Solaris:
         process = new SparcSolarisProcess(params, objFile);
         break;

       default:
         fatal("Unknown/unsupported operating system.");
     }
 #elif THE_ISA == X86_ISA
     if (objFile->getArch() != ObjectFile::X86_64 &&
         objFile->getArch() != ObjectFile::I386)
         fatal("Object file architecture does not match compiled ISA (x86).");
     switch (objFile->getOpSys()) {
       case ObjectFile::UnknownOpSys:
         warn("Unknown operating system; assuming Linux.");
         // fall through
       case ObjectFile::Linux:
         if (objFile->getArch() == ObjectFile::X86_64) {
             process = new X86_64LinuxProcess(params, objFile);
         } else {
             process = new I386LinuxProcess(params, objFile);
         }
         break;

       default:
         fatal("Unknown/unsupported operating system.");
     }
 #elif THE_ISA == MIPS_ISA
     if (objFile->getArch() != ObjectFile::Mips)
         fatal("Object file architecture does not match compiled ISA (MIPS).");
     switch (objFile->getOpSys()) {
       case ObjectFile::UnknownOpSys:
         warn("Unknown operating system; assuming Linux.");
         // fall through
       case ObjectFile::Linux:
         process = new MipsLinuxProcess(params, objFile);
         break;

       default:
         fatal("Unknown/unsupported operating system.");
     }
 #elif THE_ISA == ARM_ISA
     ObjectFile::Arch arch = objFile->getArch();
     if (arch != ObjectFile::Arm && arch != ObjectFile::Thumb &&
         arch != ObjectFile::Arm64)
         fatal("Object file architecture does not match compiled ISA (ARM).");
     switch (objFile->getOpSys()) {
       case ObjectFile::UnknownOpSys:
         warn("Unknown operating system; assuming Linux.");
         // fall through
       case ObjectFile::Linux:
         if (arch == ObjectFile::Arm64) {
             process = new ArmLinuxProcess64(params, objFile,
                                             objFile->getArch());
         } else {
             process = new ArmLinuxProcess32(params, objFile,
                                             objFile->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 (objFile->getArch() != ObjectFile::Power)
         fatal("Object file architecture does not match compiled ISA (Power).");
     switch (objFile->getOpSys()) {
       case ObjectFile::UnknownOpSys:
         warn("Unknown operating system; assuming Linux.");
         // fall through
       case ObjectFile::Linux:
         process = new PowerLinuxProcess(params, objFile);
         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;
 }

 LiveProcess *
 LiveProcessParams::create()
 {
     return LiveProcess::create(this);
 }
	/*
	* Copyright (c) 2014 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
	*/

	#include <fcntl.h>
	#include <unistd.h>

	#include <cstdio>
	#include <string>

	#include "base/loader/object_file.hh"
	#include "base/loader/symtab.hh"
	#include "base/intmath.hh"
	#include "base/statistics.hh"
	#include "config/the_isa.hh"
	#include "cpu/thread_context.hh"
	#include "mem/page_table.hh"
	#include "mem/multi_level_page_table.hh"
	#include "mem/se_translating_port_proxy.hh"
	#include "params/LiveProcess.hh"
	#include "params/Process.hh"
	#include "sim/debug.hh"
	#include "sim/process.hh"
	#include "sim/process_impl.hh"
	#include "sim/stats.hh"
	#include "sim/syscall_emul.hh"
	#include "sim/system.hh"

	#if THE_ISA == ALPHA_ISA
	#include "arch/alpha/linux/process.hh"
	#include "arch/alpha/tru64/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"
	#elif THE_ISA == X86_ISA
	#include "arch/x86/linux/process.hh"
	#elif THE_ISA == POWER_ISA
	#include "arch/power/linux/process.hh"
	#else
	#error "THE_ISA not set"
	#endif


	using namespace std;
	using namespace TheISA;

	// current number of allocated processes
	int num_processes = 0;

	template<class IntType>
	AuxVector<IntType>::AuxVector(IntType type, IntType val)
	{
	a_type = TheISA::htog(type);
	a_val = TheISA::htog(val);
	}

	template struct AuxVector<uint32_t>;
	template struct AuxVector<uint64_t>;

	Process::Process(ProcessParams * params)
	: SimObject(params), system(params->system),
	max_stack_size(params->max_stack_size),
	M5_pid(system->allocatePID()),
	useArchPT(params->useArchPT),
	pTable(useArchPT ?
	static_cast<PageTableBase *>(new ArchPageTable(name(), M5_pid, system)) :
	static_cast<PageTableBase *>(new FuncPageTable(name(), M5_pid)) ),
	initVirtMem(system->getSystemPort(), this,
	SETranslatingPortProxy::Always)
	{
	string in = params->input;
	string out = params->output;
	string err = params->errout;

	// initialize file descriptors to default: same as simulator
	int stdin_fd, stdout_fd, stderr_fd;

	if (in == "stdin" \|\| in == "cin")
	stdin_fd = STDIN_FILENO;
	else if (in == "None")
	stdin_fd = -1;
	else
	stdin_fd = Process::openInputFile(in);

	if (out == "stdout" \|\| out == "cout")
	stdout_fd = STDOUT_FILENO;
	else if (out == "stderr" \|\| out == "cerr")
	stdout_fd = STDERR_FILENO;
	else if (out == "None")
	stdout_fd = -1;
	else
	stdout_fd = Process::openOutputFile(out);

	if (err == "stdout" \|\| err == "cout")
	stderr_fd = STDOUT_FILENO;
	else if (err == "stderr" \|\| err == "cerr")
	stderr_fd = STDERR_FILENO;
	else if (err == "None")
	stderr_fd = -1;
	else if (err == out)
	stderr_fd = stdout_fd;
	else
	stderr_fd = Process::openOutputFile(err);

	// initialize first 3 fds (stdin, stdout, stderr)
	Process::FdMap *fdo = &fd_map[STDIN_FILENO];
	fdo->fd = stdin_fd;
	fdo->filename = in;
	fdo->flags = O_RDONLY;
	fdo->mode = -1;
	fdo->fileOffset = 0;

	fdo = &fd_map[STDOUT_FILENO];
	fdo->fd = stdout_fd;
	fdo->filename = out;
	fdo->flags = O_WRONLY \| O_CREAT \| O_TRUNC;
	fdo->mode = 0774;
	fdo->fileOffset = 0;

	fdo = &fd_map[STDERR_FILENO];
	fdo->fd = stderr_fd;
	fdo->filename = err;
	fdo->flags = O_WRONLY;
	fdo->mode = -1;
	fdo->fileOffset = 0;


	// mark remaining fds as free
	for (int i = 3; i <= MAX_FD; ++i) {
	fdo = &fd_map[i];
	fdo->fd = -1;
	}

	mmap_start = mmap_end = 0;
	nxm_start = nxm_end = 0;
	// other parameters will be initialized when the program is loaded
	}


	void
	Process::regStats()
	{
	using namespace Stats;

	num_syscalls
	.name(name() + ".num_syscalls")
	.desc("Number of system calls")
	;
	}

	//
	// static helper functions
	//
	int
	Process::openInputFile(const string &filename)
	{
	int fd = open(filename.c_str(), O_RDONLY);

	if (fd == -1) {
	perror(NULL);
	cerr << "unable to open \"" << filename << "\" for reading\n";
	fatal("can't open input file");
	}

	return fd;
	}


	int
	Process::openOutputFile(const string &filename)
	{
	int fd = open(filename.c_str(), O_WRONLY \| O_CREAT \| O_TRUNC, 0664);

	if (fd == -1) {
	perror(NULL);
	cerr << "unable to open \"" << filename << "\" for writing\n";
	fatal("can't open output file");
	}

	return fd;
	}

	ThreadContext *
	Process::findFreeContext()
	{
	int size = contextIds.size();
	ThreadContext *tc;
	for (int i = 0; i < size; ++i) {
	tc = system->getThreadContext(contextIds[i]);
	if (tc->status() == ThreadContext::Halted) {
	// inactive context, free to use
	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);
	}

	// map simulator fd sim_fd to target fd tgt_fd
	void
	Process::dup_fd(int sim_fd, int tgt_fd)
	{
	if (tgt_fd < 0 \|\| tgt_fd > MAX_FD)
	panic("Process::dup_fd tried to dup past MAX_FD (%d)", tgt_fd);

	Process::FdMap *fdo = &fd_map[tgt_fd];
	fdo->fd = sim_fd;
	}


	// generate new target fd for sim_fd
	int
	Process::alloc_fd(int sim_fd, string filename, int flags, int mode, bool pipe)
	{
	// in case open() returns an error, don't allocate a new fd
	if (sim_fd == -1)
	return -1;

	// find first free target fd
	for (int free_fd = 0; free_fd <= MAX_FD; ++free_fd) {
	Process::FdMap *fdo = &fd_map[free_fd];
	if (fdo->fd == -1) {
	fdo->fd = sim_fd;
	fdo->filename = filename;
	fdo->mode = mode;
	fdo->fileOffset = 0;
	fdo->flags = flags;
	fdo->isPipe = pipe;
	fdo->readPipeSource = 0;
	return free_fd;
	}
	}

	panic("Process::alloc_fd: out of file descriptors!");
	}


	// free target fd (e.g., after close)
	void
	Process::free_fd(int tgt_fd)
	{
	Process::FdMap *fdo = &fd_map[tgt_fd];
	if (fdo->fd == -1)
	warn("Process::free_fd: request to free unused fd %d", tgt_fd);

	fdo->fd = -1;
	fdo->filename = "NULL";
	fdo->mode = 0;
	fdo->fileOffset = 0;
	fdo->flags = 0;
	fdo->isPipe = false;
	fdo->readPipeSource = 0;
	}


	// look up simulator fd for given target fd
	int
	Process::sim_fd(int tgt_fd)
	{
	if (tgt_fd < 0 \|\| tgt_fd > MAX_FD)
	return -1;

	return fd_map[tgt_fd].fd;
	}

	Process::FdMap *
	Process::sim_fd_obj(int tgt_fd)
	{
	if (tgt_fd < 0 \|\| tgt_fd > MAX_FD)
	return NULL;

	return &fd_map[tgt_fd];
	}

	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);
	}

	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;
	}

	// find all offsets for currently open files and save them
	void
	Process::fix_file_offsets()
	{
	Process::FdMap *fdo_stdin = &fd_map[STDIN_FILENO];
	Process::FdMap *fdo_stdout = &fd_map[STDOUT_FILENO];
	Process::FdMap *fdo_stderr = &fd_map[STDERR_FILENO];
	string in = fdo_stdin->filename;
	string out = fdo_stdout->filename;
	string err = fdo_stderr->filename;

	// initialize file descriptors to default: same as simulator
	int stdin_fd, stdout_fd, stderr_fd;

	if (in == "stdin" \|\| in == "cin")
	stdin_fd = STDIN_FILENO;
	else if (in == "None")
	stdin_fd = -1;
	else {
	// open standard in and seek to the right location
	stdin_fd = Process::openInputFile(in);
	if (lseek(stdin_fd, fdo_stdin->fileOffset, SEEK_SET) < 0)
	panic("Unable to seek to correct location in file: %s", in);
	}

	if (out == "stdout" \|\| out == "cout")
	stdout_fd = STDOUT_FILENO;
	else if (out == "stderr" \|\| out == "cerr")
	stdout_fd = STDERR_FILENO;
	else if (out == "None")
	stdout_fd = -1;
	else {
	stdout_fd = Process::openOutputFile(out);
	if (lseek(stdout_fd, fdo_stdout->fileOffset, SEEK_SET) < 0)
	panic("Unable to seek to correct location in file: %s", out);
	}

	if (err == "stdout" \|\| err == "cout")
	stderr_fd = STDOUT_FILENO;
	else if (err == "stderr" \|\| err == "cerr")
	stderr_fd = STDERR_FILENO;
	else if (err == "None")
	stderr_fd = -1;
	else if (err == out)
	stderr_fd = stdout_fd;
	else {
	stderr_fd = Process::openOutputFile(err);
	if (lseek(stderr_fd, fdo_stderr->fileOffset, SEEK_SET) < 0)
	panic("Unable to seek to correct location in file: %s", err);
	}

	fdo_stdin->fd = stdin_fd;
	fdo_stdout->fd = stdout_fd;
	fdo_stderr->fd = stderr_fd;


	for (int free_fd = 3; free_fd <= MAX_FD; ++free_fd) {
	Process::FdMap *fdo = &fd_map[free_fd];
	if (fdo->fd != -1) {
	if (fdo->isPipe){
	if (fdo->filename == "PIPE-WRITE")
	continue;
	else {
	assert (fdo->filename == "PIPE-READ");
	//create a new pipe
	int fds[2];
	int pipe_retval = pipe(fds);

	if (pipe_retval < 0) {
	// error
	panic("Unable to create new pipe.");
	}
	fdo->fd = fds[0]; //set read pipe
	Process::FdMap *fdo_write = &fd_map[fdo->readPipeSource];
	if (fdo_write->filename != "PIPE-WRITE")
	panic ("Couldn't find write end of the pipe");

	fdo_write->fd = fds[1];//set write pipe
	}
	} else {
	//Open file
	int fd = open(fdo->filename.c_str(), fdo->flags, fdo->mode);

	if (fd == -1)
	panic("Unable to open file: %s", fdo->filename);
	fdo->fd = fd;

	//Seek to correct location before checkpoint
	if (lseek(fd,fdo->fileOffset, SEEK_SET) < 0)
	panic("Unable to seek to correct location in file: %s",
	fdo->filename);
	}
	}
	}
	}

	void
	Process::find_file_offsets()
	{
	for (int free_fd = 0; free_fd <= MAX_FD; ++free_fd) {
	Process::FdMap *fdo = &fd_map[free_fd];
	if (fdo->fd != -1) {
	fdo->fileOffset = lseek(fdo->fd, 0, SEEK_CUR);
	} else {
	fdo->filename = "NULL";
	fdo->fileOffset = 0;
	}
	}
	}

	void
	Process::setReadPipeSource(int read_pipe_fd, int source_fd)
	{
	Process::FdMap *fdo = &fd_map[read_pipe_fd];
	fdo->readPipeSource = source_fd;
	}

	void
	Process::FdMap::serialize(std::ostream &os)
	{
	SERIALIZE_SCALAR(fd);
	SERIALIZE_SCALAR(isPipe);
	SERIALIZE_SCALAR(filename);
	SERIALIZE_SCALAR(flags);
	SERIALIZE_SCALAR(readPipeSource);
	SERIALIZE_SCALAR(fileOffset);
	}

	void
	Process::FdMap::unserialize(Checkpoint *cp, const std::string &section)
	{
	UNSERIALIZE_SCALAR(fd);
	UNSERIALIZE_SCALAR(isPipe);
	UNSERIALIZE_SCALAR(filename);
	UNSERIALIZE_SCALAR(flags);
	UNSERIALIZE_SCALAR(readPipeSource);
	UNSERIALIZE_SCALAR(fileOffset);
	}

	void
	Process::serialize(std::ostream &os)
	{
	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_start);
	SERIALIZE_SCALAR(mmap_end);
	SERIALIZE_SCALAR(nxm_start);
	SERIALIZE_SCALAR(nxm_end);
	find_file_offsets();
	pTable->serialize(os);
	for (int x = 0; x <= MAX_FD; x++) {
	nameOut(os, csprintf("%s.FdMap%d", name(), x));
	fd_map[x].serialize(os);
	}
	SERIALIZE_SCALAR(M5_pid);

	}

	void
	Process::unserialize(Checkpoint *cp, const std::string &section)
	{
	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_start);
	UNSERIALIZE_SCALAR(mmap_end);
	UNSERIALIZE_SCALAR(nxm_start);
	UNSERIALIZE_SCALAR(nxm_end);
	pTable->unserialize(cp, section);
	for (int x = 0; x <= MAX_FD; x++) {
	fd_map[x].unserialize(cp, csprintf("%s.FdMap%d", section, x));
	}
	fix_file_offsets();
	UNSERIALIZE_OPT_SCALAR(M5_pid);
	// 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 instantianted value if not
	// found.
	}


	bool
	Process::map(Addr vaddr, Addr paddr, int size)
	{
	pTable->map(vaddr, paddr, size);
	return true;
	}


	////////////////////////////////////////////////////////////////////////
	//
	// LiveProcess member definitions
	//
	////////////////////////////////////////////////////////////////////////


	LiveProcess::LiveProcess(LiveProcessParams * params, ObjectFile *_objFile)
	: Process(params), objFile(_objFile),
	argv(params->cmd), envp(params->env), cwd(params->cwd)
	{
	__uid = params->uid;
	__euid = params->euid;
	__gid = params->gid;
	__egid = params->egid;
	__pid = params->pid;
	__ppid = params->ppid;

	// 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
	LiveProcess::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
	LiveProcess::getSyscallArg(ThreadContext *tc, int &i, int width)
	{
	return getSyscallArg(tc, i);
	}

	LiveProcess *
	LiveProcess::create(LiveProcessParams * params)
	{
	LiveProcess *process = NULL;

	string executable =
	params->executable == "" ? params->cmd[0] : params->executable;
	ObjectFile *objFile = createObjectFile(executable);
	if (objFile == NULL) {
	fatal("Can't load object file %s", executable);
	}

	if (objFile->isDynamic())
	fatal("Object file is a dynamic executable however only static "
	"executables are supported!\n Please recompile your "
	"executable as a static binary and try again.\n");

	#if THE_ISA == ALPHA_ISA
	if (objFile->getArch() != ObjectFile::Alpha)
	fatal("Object file architecture does not match compiled ISA (Alpha).");

	switch (objFile->getOpSys()) {
	case ObjectFile::Tru64:
	process = new AlphaTru64Process(params, objFile);
	break;

	case ObjectFile::UnknownOpSys:
	warn("Unknown operating system; assuming Linux.");
	// fall through
	case ObjectFile::Linux:
	process = new AlphaLinuxProcess(params, objFile);
	break;

	default:
	fatal("Unknown/unsupported operating system.");
	}
	#elif THE_ISA == SPARC_ISA
	if (objFile->getArch() != ObjectFile::SPARC64 &&
	objFile->getArch() != ObjectFile::SPARC32)
	fatal("Object file architecture does not match compiled ISA (SPARC).");
	switch (objFile->getOpSys()) {
	case ObjectFile::UnknownOpSys:
	warn("Unknown operating system; assuming Linux.");
	// fall through
	case ObjectFile::Linux:
	if (objFile->getArch() == ObjectFile::SPARC64) {
	process = new Sparc64LinuxProcess(params, objFile);
	} else {
	process = new Sparc32LinuxProcess(params, objFile);
	}
	break;


	case ObjectFile::Solaris:
	process = new SparcSolarisProcess(params, objFile);
	break;

	default:
	fatal("Unknown/unsupported operating system.");
	}
	#elif THE_ISA == X86_ISA
	if (objFile->getArch() != ObjectFile::X86_64 &&
	objFile->getArch() != ObjectFile::I386)
	fatal("Object file architecture does not match compiled ISA (x86).");
	switch (objFile->getOpSys()) {
	case ObjectFile::UnknownOpSys:
	warn("Unknown operating system; assuming Linux.");
	// fall through
	case ObjectFile::Linux:
	if (objFile->getArch() == ObjectFile::X86_64) {
	process = new X86_64LinuxProcess(params, objFile);
	} else {
	process = new I386LinuxProcess(params, objFile);
	}
	break;

	default:
	fatal("Unknown/unsupported operating system.");
	}
	#elif THE_ISA == MIPS_ISA
	if (objFile->getArch() != ObjectFile::Mips)
	fatal("Object file architecture does not match compiled ISA (MIPS).");
	switch (objFile->getOpSys()) {
	case ObjectFile::UnknownOpSys:
	warn("Unknown operating system; assuming Linux.");
	// fall through
	case ObjectFile::Linux:
	process = new MipsLinuxProcess(params, objFile);
	break;

	default:
	fatal("Unknown/unsupported operating system.");
	}
	#elif THE_ISA == ARM_ISA
	ObjectFile::Arch arch = objFile->getArch();
	if (arch != ObjectFile::Arm && arch != ObjectFile::Thumb &&
	arch != ObjectFile::Arm64)
	fatal("Object file architecture does not match compiled ISA (ARM).");
	switch (objFile->getOpSys()) {
	case ObjectFile::UnknownOpSys:
	warn("Unknown operating system; assuming Linux.");
	// fall through
	case ObjectFile::Linux:
	if (arch == ObjectFile::Arm64) {
	process = new ArmLinuxProcess64(params, objFile,
	objFile->getArch());
	} else {
	process = new ArmLinuxProcess32(params, objFile,
	objFile->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 (objFile->getArch() != ObjectFile::Power)
	fatal("Object file architecture does not match compiled ISA (Power).");
	switch (objFile->getOpSys()) {
	case ObjectFile::UnknownOpSys:
	warn("Unknown operating system; assuming Linux.");
	// fall through
	case ObjectFile::Linux:
	process = new PowerLinuxProcess(params, objFile);
	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;
	}

	LiveProcess *
	LiveProcessParams::create()
	{
	return LiveProcess::create(this);
	}