text: /*
   * Copyright (c) 2004-2005 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: Gabe Black
   *          Ali Saidi
   *          Korey Sewell
   */
  
  #include "arch/mips/process.hh"
  
  #include "arch/mips/isa_traits.hh"
  #include "base/loader/elf_object.hh"
  #include "base/loader/object_file.hh"
  #include "base/misc.hh"
  #include "cpu/thread_context.hh"
  #include "debug/Loader.hh"
  #include "mem/page_table.hh"
  #include "sim/process.hh"
  #include "sim/process_impl.hh"
  #include "sim/syscall_return.hh"
  #include "sim/system.hh"
  
  using namespace std;
  using namespace MipsISA;
  
  MipsLiveProcess::MipsLiveProcess(LiveProcessParams * params,
          ObjectFile *objFile)
      : LiveProcess(params, objFile)
  {
      // Set up stack. On MIPS, stack starts at the top of kuseg
      // user address space. MIPS stack grows down from here
      stack_base = 0x7FFFFFFF;
  
      // Set pointer for next thread stack.  Reserve 8M for main stack.
      next_thread_stack_base = stack_base - (8 * 1024 * 1024);
  
      // Set up break point (Top of Heap)
      brk_point = objFile->dataBase() + objFile->dataSize() + objFile->bssSize();
      brk_point = roundUp(brk_point, PageBytes);
  
      // Set up region for mmaps.  Start it 1GB above the top of the heap.
      mmap_end = brk_point + 0x40000000L;
  }
  
  void
  MipsLiveProcess::initState()
  {
      LiveProcess::initState();
  
      argsInit<uint32_t>(PageBytes);
  }
  
  template<class IntType>
  void
  MipsLiveProcess::argsInit(int pageSize)
  {
      int intSize = sizeof(IntType);
  
      // Patch the ld_bias for dynamic executables.
      updateBias();
  
      // load object file into target memory
      objFile->loadSections(initVirtMem);
  
      typedef AuxVector<IntType> auxv_t;
      std::vector<auxv_t> auxv;
  
      ElfObject * elfObject = dynamic_cast<ElfObject *>(objFile);
      if (elfObject)
      {
          // Set the system page size
          auxv.push_back(auxv_t(M5_AT_PAGESZ, MipsISA::PageBytes));
          // Set the frequency at which time() increments
          auxv.push_back(auxv_t(M5_AT_CLKTCK, 100));
          // For statically linked executables, this is the virtual
          // address of the program header tables if they appear in the
          // executable image.
          auxv.push_back(auxv_t(M5_AT_PHDR, elfObject->programHeaderTable()));
          DPRINTF(Loader, "auxv at PHDR %08p\n", elfObject->programHeaderTable());
          // This is the size of a program header entry from the elf file.
          auxv.push_back(auxv_t(M5_AT_PHENT, elfObject->programHeaderSize()));
          // This is the number of program headers from the original elf file.
          auxv.push_back(auxv_t(M5_AT_PHNUM, elfObject->programHeaderCount()));
          // This is the base address of the ELF interpreter; it should be
          // zero for static executables or contain the base address for
          // dynamic executables.
          auxv.push_back(auxv_t(M5_AT_BASE, getBias()));
          //The entry point to the program
          auxv.push_back(auxv_t(M5_AT_ENTRY, objFile->entryPoint()));
          //Different user and group IDs
          auxv.push_back(auxv_t(M5_AT_UID, uid()));
          auxv.push_back(auxv_t(M5_AT_EUID, euid()));
          auxv.push_back(auxv_t(M5_AT_GID, gid()));
          auxv.push_back(auxv_t(M5_AT_EGID, egid()));
      }
  
      // Calculate how much space we need for arg & env & auxv arrays.
      int argv_array_size = intSize * (argv.size() + 1);
      int envp_array_size = intSize * (envp.size() + 1);
      int auxv_array_size = intSize * 2 * (auxv.size() + 1);
  
      int arg_data_size = 0;
      for (vector<string>::size_type i = 0; i < argv.size(); ++i) {
          arg_data_size += argv[i].size() + 1;
      }
      int env_data_size = 0;
      for (vector<string>::size_type i = 0; i < envp.size(); ++i) {
          env_data_size += envp[i].size() + 1;
      }
  
      int space_needed =
          argv_array_size +
          envp_array_size +
          auxv_array_size +
          arg_data_size +
          env_data_size;
  
      // set bottom of stack
      stack_min = stack_base - space_needed;
      // align it
      stack_min = roundDown(stack_min, pageSize);
      stack_size = stack_base - stack_min;
      // map memory
      allocateMem(stack_min, roundUp(stack_size, pageSize));
  
      // map out initial stack contents
      IntType argv_array_base = stack_min + intSize; // room for argc
      IntType envp_array_base = argv_array_base + argv_array_size;
      IntType auxv_array_base = envp_array_base + envp_array_size;
      IntType arg_data_base = auxv_array_base + auxv_array_size;
      IntType env_data_base = arg_data_base + arg_data_size;
  
      // write contents to stack
      IntType argc = argv.size();
  
      argc = htog((IntType)argc);
  
      initVirtMem.writeBlob(stack_min, (uint8_t*)&argc, intSize);
  
      copyStringArray(argv, argv_array_base, arg_data_base, initVirtMem);
  
      copyStringArray(envp, envp_array_base, env_data_base, initVirtMem);
  
      // Copy the aux vector
      for (typename vector<auxv_t>::size_type x = 0; x < auxv.size(); x++) {
          initVirtMem.writeBlob(auxv_array_base + x * 2 * intSize,
                  (uint8_t*)&(auxv[x].a_type), intSize);
          initVirtMem.writeBlob(auxv_array_base + (x * 2 + 1) * intSize,
                  (uint8_t*)&(auxv[x].a_val), intSize);
      }
  
      // Write out the terminating zeroed auxilliary vector
      for (unsigned i = 0; i < 2; i++) {
          const IntType zero = 0;
          const Addr addr = auxv_array_base + 2 * intSize * (auxv.size() + i);
          initVirtMem.writeBlob(addr, (uint8_t*)&zero, intSize);
      }
  
      ThreadContext *tc = system->getThreadContext(contextIds[0]);
  
      setSyscallArg(tc, 0, argc);
      setSyscallArg(tc, 1, argv_array_base);
      tc->setIntReg(StackPointerReg, stack_min);
  
      tc->pcState(getStartPC());
  }
  
  
  MipsISA::IntReg
  MipsLiveProcess::getSyscallArg(ThreadContext *tc, int &i)
  {
      assert(i < 6);
      return tc->readIntReg(FirstArgumentReg + i++);
  }
  
  void
  MipsLiveProcess::setSyscallArg(ThreadContext *tc,
          int i, MipsISA::IntReg val)
  {
      assert(i < 6);
      tc->setIntReg(FirstArgumentReg + i, val);
  }
  
  void
  MipsLiveProcess::setSyscallReturn(ThreadContext *tc, SyscallReturn sysret)
  {
      if (sysret.successful()) {
          // no error
          tc->setIntReg(SyscallSuccessReg, 0);
          tc->setIntReg(ReturnValueReg, sysret.returnValue());
      } else {
          // got an error, return details
          tc->setIntReg(SyscallSuccessReg, (IntReg) -1);
          tc->setIntReg(ReturnValueReg, sysret.errnoValue());
      }
  }
  