示例#1
0
文件: main.c 项目: mwilbur/minix
/*===========================================================================*
 *		            sef_cb_init_fresh                                *
 *===========================================================================*/
PRIVATE int sef_cb_init_fresh(int type, sef_init_info_t *info)
{
/* Initialize the reincarnation server. */
  struct boot_image *ip;
  int s,i;
  int nr_image_srvs, nr_image_priv_srvs, nr_uncaught_init_srvs;
  struct rproc *rp;
  struct rproc *replica_rp;
  struct rprocpub *rpub;
  struct boot_image image[NR_BOOT_PROCS];
  struct boot_image_priv *boot_image_priv;
  struct boot_image_sys *boot_image_sys;
  struct boot_image_dev *boot_image_dev;
  int pid, replica_pid;
  endpoint_t replica_endpoint;
  int ipc_to;
  int *calls;
  int all_c[] = { ALL_C, NULL_C };
  int no_c[] = {  NULL_C };

  /* See if we run in verbose mode. */
  env_parse("rs_verbose", "d", 0, &rs_verbose, 0, 1);

  if ((s = sys_getinfo(GET_HZ, &system_hz, sizeof(system_hz), 0, 0)) != OK)
	  panic("Cannot get system timer frequency\n");

  /* Initialize the global init descriptor. */
  rinit.rproctab_gid = cpf_grant_direct(ANY, (vir_bytes) rprocpub,
      sizeof(rprocpub), CPF_READ);
  if(!GRANT_VALID(rinit.rproctab_gid)) {
      panic("unable to create rprocpub table grant: %d", rinit.rproctab_gid);
  }

  /* Initialize some global variables. */
  rupdate.flags = 0;
  shutting_down = FALSE;

  /* Get a copy of the boot image table. */
  if ((s = sys_getimage(image)) != OK) {
      panic("unable to get copy of boot image table: %d", s);
  }

  /* Determine the number of system services in the boot image table. */
  nr_image_srvs = 0;
  for(i=0;i<NR_BOOT_PROCS;i++) {
      ip = &image[i];

      /* System services only. */
      if(iskerneln(_ENDPOINT_P(ip->endpoint))) {
          continue;
      }
      nr_image_srvs++;
  }

  /* Determine the number of entries in the boot image priv table and make sure
   * it matches the number of system services in the boot image table.
   */
  nr_image_priv_srvs = 0;
  for (i=0; boot_image_priv_table[i].endpoint != NULL_BOOT_NR; i++) {
      boot_image_priv = &boot_image_priv_table[i];

      /* System services only. */
      if(iskerneln(_ENDPOINT_P(boot_image_priv->endpoint))) {
          continue;
      }
      nr_image_priv_srvs++;
  }
  if(nr_image_srvs != nr_image_priv_srvs) {
	panic("boot image table and boot image priv table mismatch");
  }

  /* Reset the system process table. */
  for (rp=BEG_RPROC_ADDR; rp<END_RPROC_ADDR; rp++) {
      rp->r_flags = 0;
      rp->r_pub = &rprocpub[rp - rproc];
      rp->r_pub->in_use = FALSE;
  }

  /* Initialize the system process table in 4 steps, each of them following
   * the appearance of system services in the boot image priv table.
   * - Step 1: set priviliges, sys properties, and dev properties (if any)
   * for every system service.
   */
  for (i=0; boot_image_priv_table[i].endpoint != NULL_BOOT_NR; i++) {
      boot_image_priv = &boot_image_priv_table[i];

      /* System services only. */
      if(iskerneln(_ENDPOINT_P(boot_image_priv->endpoint))) {
          continue;
      }

      /* Lookup the corresponding entries in other tables. */
      boot_image_info_lookup(boot_image_priv->endpoint, image,
          &ip, NULL, &boot_image_sys, &boot_image_dev);
      rp = &rproc[boot_image_priv - boot_image_priv_table];
      rpub = rp->r_pub;

      /*
       * Set privileges.
       */
      /* Get label. */
      strcpy(rpub->label, boot_image_priv->label);

      /* Force a static priv id for system services in the boot image. */
      rp->r_priv.s_id = static_priv_id(
          _ENDPOINT_P(boot_image_priv->endpoint));
      
      /* Initialize privilege bitmaps and signal manager. */
      rp->r_priv.s_flags = boot_image_priv->flags;          /* priv flags */
      rp->r_priv.s_trap_mask= SRV_OR_USR(rp, SRV_T, USR_T); /* traps */
      ipc_to = SRV_OR_USR(rp, SRV_M, USR_M);                /* targets */
      fill_send_mask(&rp->r_priv.s_ipc_to, ipc_to == ALL_M);
      rp->r_priv.s_sig_mgr= SRV_OR_USR(rp, SRV_SM, USR_SM); /* sig mgr */
      rp->r_priv.s_bak_sig_mgr = NONE;                      /* backup sig mgr */
      
      /* Initialize kernel call mask bitmap. */
      calls = SRV_OR_USR(rp, SRV_KC, USR_KC) == ALL_C ? all_c : no_c;
      fill_call_mask(calls, NR_SYS_CALLS,
          rp->r_priv.s_k_call_mask, KERNEL_CALL, TRUE);

      /* Set the privilege structure. */
      if(boot_image_priv->endpoint != RS_PROC_NR) {
          if ((s = sys_privctl(ip->endpoint, SYS_PRIV_SET_SYS, &(rp->r_priv)))
              != OK) {
              panic("unable to set privilege structure: %d", s);
          }
      }

      /* Synch the privilege structure with the kernel. */
      if ((s = sys_getpriv(&(rp->r_priv), ip->endpoint)) != OK) {
          panic("unable to synch privilege structure: %d", s);
      }

      /*
       * Set sys properties.
       */
      rpub->sys_flags = boot_image_sys->flags;        /* sys flags */

      /*
       * Set dev properties.
       */
      rpub->dev_flags = boot_image_dev->flags;        /* device flags */
      rpub->dev_nr = boot_image_dev->dev_nr;          /* major device number */
      rpub->dev_style = boot_image_dev->dev_style;    /* device style */
      rpub->dev_style2 = boot_image_dev->dev_style2;  /* device style 2 */

      /* Get process name. */
      strcpy(rpub->proc_name, ip->proc_name);

      /* Build command settings. */
      rp->r_cmd[0]= '\0';
      rp->r_script[0]= '\0';
      build_cmd_dep(rp);

      /* Initialize vm call mask bitmap. */
      calls = SRV_OR_USR(rp, SRV_VC, USR_VC) == ALL_C ? all_c : no_c;
      fill_call_mask(calls, NR_VM_CALLS, rpub->vm_call_mask, VM_RQ_BASE, TRUE);

      /* Scheduling parameters. */
      rp->r_scheduler = SRV_OR_USR(rp, SRV_SCH, USR_SCH);
      rp->r_priority = SRV_OR_USR(rp, SRV_Q, USR_Q);
      rp->r_quantum = SRV_OR_USR(rp, SRV_QT, USR_QT);

      /* Get some settings from the boot image table. */
      rpub->endpoint = ip->endpoint;

      /* Set some defaults. */
      rp->r_old_rp = NULL;                     /* no old version yet */
      rp->r_new_rp = NULL;                     /* no new version yet */
      rp->r_prev_rp = NULL;                    /* no prev replica yet */
      rp->r_next_rp = NULL;                    /* no next replica yet */
      rp->r_uid = 0;                           /* root */
      rp->r_check_tm = 0;                      /* not checked yet */
      getuptime(&rp->r_alive_tm);              /* currently alive */
      rp->r_stop_tm = 0;                       /* not exiting yet */
      rp->r_restarts = 0;                      /* no restarts so far */
      rp->r_period = 0;                        /* no period yet */
      rp->r_exec = NULL;                       /* no in-memory copy yet */
      rp->r_exec_len = 0;

      /* Mark as in use and active. */
      rp->r_flags = RS_IN_USE | RS_ACTIVE;
      rproc_ptr[_ENDPOINT_P(rpub->endpoint)]= rp;
      rpub->in_use = TRUE;
  }

  /* - Step 2: allow every system service in the boot image to run. */
  nr_uncaught_init_srvs = 0;
  for (i=0; boot_image_priv_table[i].endpoint != NULL_BOOT_NR; i++) {
      boot_image_priv = &boot_image_priv_table[i];

      /* System services only. */
      if(iskerneln(_ENDPOINT_P(boot_image_priv->endpoint))) {
          continue;
      }

      /* Lookup the corresponding slot in the system process table. */
      rp = &rproc[boot_image_priv - boot_image_priv_table];
      rpub = rp->r_pub;

      /* RS is already running as we speak. */
      if(boot_image_priv->endpoint == RS_PROC_NR) {
          if ((s = init_service(rp, SEF_INIT_FRESH)) != OK) {
              panic("unable to initialize RS: %d", s);
          }
          continue;
      }

      /* Allow the service to run. */
      if ((s = sched_init_proc(rp)) != OK) {
          panic("unable to initialize scheduling: %d", s);
      }
      if ((s = sys_privctl(rpub->endpoint, SYS_PRIV_ALLOW, NULL)) != OK) {
          panic("unable to initialize privileges: %d", s);
      }

      /* Initialize service. We assume every service will always get
       * back to us here at boot time.
       */
      if(boot_image_priv->flags & SYS_PROC) {
          if ((s = init_service(rp, SEF_INIT_FRESH)) != OK) {
              panic("unable to initialize service: %d", s);
          }
          if(rpub->sys_flags & SF_SYNCH_BOOT) {
              /* Catch init ready message now to synchronize. */
              catch_boot_init_ready(rpub->endpoint);
          }
          else {
              /* Catch init ready message later. */
              nr_uncaught_init_srvs++;
          }
      }
  }

  /* - Step 3: let every system service complete initialization by
   * catching all the init ready messages left.
   */
  while(nr_uncaught_init_srvs) {
      catch_boot_init_ready(ANY);
      nr_uncaught_init_srvs--;
  }

  /* - Step 4: all the system services in the boot image are now running.
   * Complete the initialization of the system process table in collaboration
   * with other system services.
   */
  for (i=0; boot_image_priv_table[i].endpoint != NULL_BOOT_NR; i++) {
      boot_image_priv = &boot_image_priv_table[i];

      /* System services only. */
      if(iskerneln(_ENDPOINT_P(boot_image_priv->endpoint))) {
          continue;
      }

      /* Lookup the corresponding slot in the system process table. */
      rp = &rproc[boot_image_priv - boot_image_priv_table];
      rpub = rp->r_pub;

      /* Get pid from PM. */
      rp->r_pid = getnpid(rpub->endpoint);
      if(rp->r_pid == -1) {
          panic("unable to get pid");
      }
  }

  /* Set alarm to periodically check service status. */
  if (OK != (s=sys_setalarm(RS_DELTA_T, 0)))
      panic("couldn't set alarm: %d", s);

  /* Now create a new RS instance with a private page table and let the current
   * instance live update into the replica. Clone RS' own slot first.
   */
  rp = rproc_ptr[_ENDPOINT_P(RS_PROC_NR)];
  if((s = clone_slot(rp, &replica_rp)) != OK) {
      panic("unable to clone current RS instance: %d", s);
  }

  /* Fork a new RS instance. */
  pid = srv_fork();
  if(pid == -1) {
      panic("unable to fork a new RS instance");
  }
  replica_pid = pid ? pid : getpid();
  replica_endpoint = getnprocnr(replica_pid);
  replica_rp->r_pid = replica_pid;
  replica_rp->r_pub->endpoint = replica_endpoint;

  if(pid == 0) {
      /* New RS instance running. */

      /* Live update the old instance into the new one. */
      s = update_service(&rp, &replica_rp, RS_SWAP);
      if(s != OK) {
          panic("unable to live update RS: %d", s);
      }
      cpf_reload();

      /* Clean up the old RS instance, the new instance will take over. */
      cleanup_service(rp);

      /* Map out our own text and data. */
      unmap_ok = 1;
      _minix_unmapzero();

      /* Ask VM to pin memory for the new RS instance. */
      if((s = vm_memctl(RS_PROC_NR, VM_RS_MEM_PIN)) != OK) {
          panic("unable to pin memory for the new RS instance: %d", s);
      }
  }
  else {
      /* Old RS instance running. */

      /* Set up privileges for the new instance and let it run. */
      s = sys_privctl(replica_endpoint, SYS_PRIV_SET_SYS, &(replica_rp->r_priv));
      if(s != OK) {
          panic("unable to set privileges for the new RS instance: %d", s);
      }
      if ((s = sched_init_proc(replica_rp)) != OK) {
          panic("unable to initialize RS replica scheduling: %d", s);
      }
      s = sys_privctl(replica_endpoint, SYS_PRIV_YIELD, NULL);
      if(s != OK) {
          panic("unable to yield control to the new RS instance: %d", s);
      }
      NOT_REACHABLE;
  }

  return(OK);
}
示例#2
0
/*===========================================================================*
 *		            sef_cb_init_fresh                                *
 *===========================================================================*/
PRIVATE int sef_cb_init_fresh(int type, sef_init_info_t *info)
{
/* Initialize the reincarnation server. */
  struct sigaction sa;
  struct boot_image *ip;
  int s,i,j;
  int nr_image_srvs, nr_image_priv_srvs, nr_uncaught_init_srvs;
  struct rproc *rp;
  struct rprocpub *rpub;
  struct boot_image image[NR_BOOT_PROCS];
  struct mproc mproc[NR_PROCS];
  struct exec header;
  struct boot_image_priv *boot_image_priv;
  struct boot_image_sys *boot_image_sys;
  struct boot_image_dev *boot_image_dev;

  /* See if we run in verbose mode. */
  env_parse("rs_verbose", "d", 0, &rs_verbose, 0, 1);

  /* Initialize the global init descriptor. */
  rinit.rproctab_gid = cpf_grant_direct(ANY, (vir_bytes) rprocpub,
      sizeof(rprocpub), CPF_READ);
  if(!GRANT_VALID(rinit.rproctab_gid)) {
      panic("RS", "unable to create rprocpub table grant", rinit.rproctab_gid);
  }

  /* Initialize the global update descriptor. */
  rupdate.flags = 0;

  /* Get a copy of the boot image table. */
  if ((s = sys_getimage(image)) != OK) {
      panic("RS", "unable to get copy of boot image table", s);
  }

  /* Determine the number of system services in the boot image table and
   * compute the size required for the boot image buffer.
   */
  nr_image_srvs = 0;
  boot_image_buffer_size = 0;
  for(i=0;i<NR_BOOT_PROCS;i++) {
      ip = &image[i];

      /* System services only. */
      if(iskerneln(_ENDPOINT_P(ip->endpoint))) {
          continue;
      }
      nr_image_srvs++;

      /* Lookup the corresponding entry in the boot image sys table. */
      boot_image_info_lookup(ip->endpoint, image,
          NULL, NULL, &boot_image_sys, NULL);

      /* If we must keep a copy of this system service, read the header
       * and increase the size of the boot image buffer.
       */
      if(boot_image_sys->flags & SF_USE_COPY) {
          if((s = sys_getaoutheader(&header, i)) != OK) {
              panic("RS", "unable to get copy of a.out header", s);
          }
          boot_image_buffer_size += header.a_hdrlen
              + header.a_text + header.a_data;
      }
  }

  /* Determine the number of entries in the boot image priv table and make sure
   * it matches the number of system services in the boot image table.
   */
  nr_image_priv_srvs = 0;
  for (i=0; boot_image_priv_table[i].endpoint != NULL_BOOT_NR; i++) {
      boot_image_priv = &boot_image_priv_table[i];

      /* System services only. */
      if(iskerneln(_ENDPOINT_P(boot_image_priv->endpoint))) {
          continue;
      }
      nr_image_priv_srvs++;
  }
  if(nr_image_srvs != nr_image_priv_srvs) {
      panic("RS", "boot image table and boot image priv table mismatch",
          NO_NUM);
  }

  /* Allocate boot image buffer. */
  if(boot_image_buffer_size > 0) {
      boot_image_buffer = rs_startup_sbrk(boot_image_buffer_size);
      if(boot_image_buffer == (char *) -1) {
          panic("RS", "unable to allocate boot image buffer", NO_NUM);
      }
  }

  /* Reset the system process table. */
  for (rp=BEG_RPROC_ADDR; rp<END_RPROC_ADDR; rp++) {
      rp->r_flags = 0;
      rp->r_pub = &rprocpub[rp - rproc];
      rp->r_pub->in_use = FALSE;
  }

  /* Initialize the system process table in 4 steps, each of them following
   * the appearance of system services in the boot image priv table.
   * - Step 1: get a copy of the executable image of every system service that
   * requires it while it is not yet running.
   * In addition, set priviliges, sys properties, and dev properties (if any)
   * for every system service.
   */
  for (i=0; boot_image_priv_table[i].endpoint != NULL_BOOT_NR; i++) {
      boot_image_priv = &boot_image_priv_table[i];

      /* System services only. */
      if(iskerneln(_ENDPOINT_P(boot_image_priv->endpoint))) {
          continue;
      }

      /* Lookup the corresponding entries in other tables. */
      boot_image_info_lookup(boot_image_priv->endpoint, image,
          &ip, NULL, &boot_image_sys, &boot_image_dev);
      rp = &rproc[boot_image_priv - boot_image_priv_table];
      rpub = rp->r_pub;

      /*
       * Get a copy of the executable image if required.
       */
      rp->r_exec_len = 0;
      rp->r_exec = NULL;
      if(boot_image_sys->flags & SF_USE_COPY) {
          exec_image_copy(ip - image, ip, rp);
      }

      /*
       * Set privileges.
       */
      /* Get label. */
      strcpy(rpub->label, boot_image_priv->label);

      if(boot_image_priv->endpoint != RS_PROC_NR) {
          /* Force a static priv id for system services in the boot image. */
          rp->r_priv.s_id = static_priv_id(
              _ENDPOINT_P(boot_image_priv->endpoint));

          /* Initialize privilege bitmaps. */
          rp->r_priv.s_flags = boot_image_priv->flags;         /* priv flags */
          rp->r_priv.s_trap_mask = boot_image_priv->trap_mask; /* traps */
          memcpy(&rp->r_priv.s_ipc_to, &boot_image_priv->ipc_to,
                            sizeof(rp->r_priv.s_ipc_to));      /* targets */

          /* Initialize kernel call mask bitmap from unordered set. */
          fill_call_mask(boot_image_priv->k_calls, NR_SYS_CALLS,
              rp->r_priv.s_k_call_mask, KERNEL_CALL, TRUE);

          /* Set the privilege structure. */
          if ((s = sys_privctl(ip->endpoint, SYS_PRIV_SET_SYS, &(rp->r_priv)))
              != OK) {
              panic("RS", "unable to set privilege structure", s);
          }
      }

      /* Synch the privilege structure with the kernel. */
      if ((s = sys_getpriv(&(rp->r_priv), ip->endpoint)) != OK) {
          panic("RS", "unable to synch privilege structure", s);
      }

      /*
       * Set sys properties.
       */
      rpub->sys_flags = boot_image_sys->flags;        /* sys flags */

      /*
       * Set dev properties.
       */
      rpub->dev_nr = boot_image_dev->dev_nr;          /* major device number */
      rpub->dev_style = boot_image_dev->dev_style;    /* device style */
      rpub->period = boot_image_dev->period;          /* heartbeat period */

      /* Get process name. */
      strcpy(rpub->proc_name, ip->proc_name);

      /* Get command settings. */
      rp->r_cmd[0]= '\0';
      rp->r_argv[0] = rp->r_cmd;
      rp->r_argv[1] = NULL;
      rp->r_argc = 1;
      rp->r_script[0]= '\0';

      /* Initialize vm call mask bitmap from unordered set. */
      fill_call_mask(boot_image_priv->vm_calls, NR_VM_CALLS,
          rpub->vm_call_mask, VM_RQ_BASE, TRUE);

      /* Get some settings from the boot image table. */
      rp->r_nice = ip->priority;
      rpub->endpoint = ip->endpoint;

      /* Set some defaults. */
      rp->r_uid = 0;                           /* root */
      rp->r_check_tm = 0;                      /* not checked yet */
      getuptime(&rp->r_alive_tm);              /* currently alive */
      rp->r_stop_tm = 0;                       /* not exiting yet */
      rp->r_restarts = 0;                      /* no restarts so far */
      rp->r_set_resources = 0;                 /* don't set resources */

      /* Mark as in use. */
      rp->r_flags = RS_IN_USE;
      rproc_ptr[_ENDPOINT_P(rpub->endpoint)]= rp;
      rpub->in_use = TRUE;
  }

  /* - Step 2: allow every system service in the boot image to run.
   */
  nr_uncaught_init_srvs = 0;
  for (i=0; boot_image_priv_table[i].endpoint != NULL_BOOT_NR; i++) {
      boot_image_priv = &boot_image_priv_table[i];

      /* System services only. */
      if(iskerneln(_ENDPOINT_P(boot_image_priv->endpoint))) {
          continue;
      }

      /* Ignore RS. */
      if(boot_image_priv->endpoint == RS_PROC_NR) {
          continue;
      }

      /* Lookup the corresponding slot in the system process table. */
      rp = &rproc[boot_image_priv - boot_image_priv_table];
      rpub = rp->r_pub;

      /* Allow the service to run. */
      if ((s = sys_privctl(rpub->endpoint, SYS_PRIV_ALLOW, NULL)) != OK) {
          panic("RS", "unable to initialize privileges", s);
      }

      /* Initialize service. We assume every service will always get
       * back to us here at boot time.
       */
      if(boot_image_priv->flags & SYS_PROC) {
          if ((s = init_service(rp, SEF_INIT_FRESH)) != OK) {
              panic("RS", "unable to initialize service", s);
          }
          if(rpub->sys_flags & SF_SYNCH_BOOT) {
              /* Catch init ready message now to synchronize. */
              catch_boot_init_ready(rpub->endpoint);
          }
          else {
              /* Catch init ready message later. */
              nr_uncaught_init_srvs++;
          }
      }
  }

  /* - Step 3: let every system service complete initialization by
   * catching all the init ready messages left.
   */
  while(nr_uncaught_init_srvs) {
      catch_boot_init_ready(ANY);
      nr_uncaught_init_srvs--;
  }

  /* - Step 4: all the system services in the boot image are now running.
   * Complete the initialization of the system process table in collaboration
   * with other system processes.
   */
  if ((s = getsysinfo(PM_PROC_NR, SI_PROC_TAB, mproc)) != OK) {
      panic("RS", "unable to get copy of PM process table", s);
  }
  for (i=0; boot_image_priv_table[i].endpoint != NULL_BOOT_NR; i++) {
      boot_image_priv = &boot_image_priv_table[i];

      /* System services only. */
      if(iskerneln(_ENDPOINT_P(boot_image_priv->endpoint))) {
          continue;
      }

      /* Lookup the corresponding slot in the system process table. */
      rp = &rproc[boot_image_priv - boot_image_priv_table];
      rpub = rp->r_pub;

      /* Get pid from PM process table. */
      rp->r_pid = NO_PID;
      for (j = 0; j < NR_PROCS; j++) {
          if (mproc[j].mp_endpoint == rpub->endpoint) {
              rp->r_pid = mproc[j].mp_pid;
              break;
          }
      }
      if(j == NR_PROCS) {
          panic("RS", "unable to get pid", NO_NUM);
      }
  }

  /*
   * Now complete RS initialization process in collaboration with other
   * system services.
   */
  /* Let the rest of the system know about our dynamically allocated buffer. */
  if(boot_image_buffer_size > 0) {
      boot_image_buffer = rs_startup_sbrk_synch(boot_image_buffer_size);
      if(boot_image_buffer == (char *) -1) {
          panic("RS", "unable to synch boot image buffer", NO_NUM);
      }
  }

  /* Set alarm to periodically check service status. */
  if (OK != (s=sys_setalarm(RS_DELTA_T, 0)))
      panic("RS", "couldn't set alarm", s);

  /* Install signal handlers. Ask PM to transform signal into message. */
  sa.sa_handler = SIG_MESS;
  sigemptyset(&sa.sa_mask);
  sa.sa_flags = 0;
  if (sigaction(SIGCHLD,&sa,NULL)<0) panic("RS","sigaction failed", errno);
  if (sigaction(SIGTERM,&sa,NULL)<0) panic("RS","sigaction failed", errno);

  /* Initialize the exec pipe. */
  if (pipe(exec_pipe) == -1)
	panic("RS", "pipe failed", errno);
  if (fcntl(exec_pipe[0], F_SETFD,
	fcntl(exec_pipe[0], F_GETFD) | FD_CLOEXEC) == -1)
  {
	panic("RS", "fcntl set FD_CLOEXEC on pipe input failed", errno);
  }
  if (fcntl(exec_pipe[1], F_SETFD,
	fcntl(exec_pipe[1], F_GETFD) | FD_CLOEXEC) == -1)
  {
	panic("RS", "fcntl set FD_CLOEXEC on pipe output failed", errno);
  }
  if (fcntl(exec_pipe[0], F_SETFL,
	fcntl(exec_pipe[0], F_GETFL) | O_NONBLOCK) == -1)
  {
	panic("RS", "fcntl set O_NONBLOCK on pipe input failed", errno);
  }

 /* Map out our own text and data. This is normally done in crtso.o
  * but RS is an exception - we don't get to talk to VM so early on.
  * That's why we override munmap() and munmap_text() in utility.c.
  *
  * _minix_unmapzero() is the same code in crtso.o that normally does
  * it on startup. It's best that it's there as crtso.o knows exactly
  * what the ranges are of the filler data.
  */
  unmap_ok = 1;
  _minix_unmapzero();

  return(OK);
}