[PATCH 03/17] Add proc_set_init_task, make runsystem pid 1

[Justus Winter]

* hurd/process.defs (proc_set_init_task): New procedure.
* hurd/process_reply.defs (proc_set_init_task): Likewise.
* hurd/process_request.defs (proc_set_init_task): Likewise.
* include/pids.h: Add HURD_PID_INIT as 1, adjust others accordingly.
* init/init.c (start_child): Register the child task.
* proc/proc.h (init_proc): New variable.
(create_startup_proc): Rename to create_init_proc.
* proc/main.c (main): Create placeholder proc object for pid 1.
* proc/mgt.c: Use init_proc instead of startup_proc, as the former is
  the new root of the process tree.
(create_startup_proc): Rename to create_init_proc.
(S_proc_set_init_task): New function.
---
 hurd/process.defs         |    8 +++++
 hurd/process_reply.defs   |    2 ++
 hurd/process_request.defs |    9 ++++++
 include/pids.h            |    5 +--
 init/init.c               |    2 +-
 proc/main.c               |    9 ++++--
 proc/mgt.c                |   76 +++++++++++++++++++++++++++++++++------------
 proc/proc.h               |    8 +++--
 8 files changed, 91 insertions(+), 28 deletions(-)

diff --git a/hurd/process.defs b/hurd/process.defs
index 43cc9f2..95d63f5 100644
--- a/hurd/process.defs
+++ b/hurd/process.defs
@@ -370,3 +370,11 @@ routine proc_getnports (
        process: process_t;
        which: pid_t;
        out nports: mach_msg_type_number_t);
+
+/*** Routines related to early server bootstrapping ***/
+
+/* Set the task of process HURD_PID_INIT. Only the startup process
+   HURD_PID_STARTUP may use this interface.  */
+routine proc_set_init_task (
+       process: process_t;
+       task: task_t);
diff --git a/hurd/process_reply.defs b/hurd/process_reply.defs
index bb66399..3a946c7 100644
--- a/hurd/process_reply.defs
+++ b/hurd/process_reply.defs
@@ -174,3 +174,5 @@ simpleroutine proc_getnports (
        reply_port: reply_port_t;
        RETURN_CODE_ARG;
        nports: mach_msg_type_number_t);
+
+skip; /* proc_set_init_task */
diff --git a/hurd/process_request.defs b/hurd/process_request.defs
index 80a2828..5b87166 100644
--- a/hurd/process_request.defs
+++ b/hurd/process_request.defs
@@ -371,3 +371,12 @@ simpleroutine proc_getnports_request (
        process: process_t;
        ureplyport reply: reply_port_t;
        which: pid_t);
+
+/*** Routines related to early server bootstrapping ***/
+
+/* Set the task of process HURD_PID_INIT. Only the startup process
+   HURD_PID_STARTUP may use this interface.  */
+simpleroutine proc_set_init_task_request (
+       process: process_t;
+       ureplyport reply: reply_port_t;
+       task: task_t);
diff --git a/include/pids.h b/include/pids.h
index 485916b..ccb7fff 100644
--- a/include/pids.h
+++ b/include/pids.h
@@ -23,7 +23,8 @@
 #define _HURD_PROCESSES_H
 
 #define HURD_PID_PROC          0
-#define HURD_PID_STARTUP       1
-#define HURD_PID_KERNEL                2
+#define HURD_PID_INIT          1
+#define HURD_PID_STARTUP       2
+#define HURD_PID_KERNEL                3
 
 #endif  /* _HURD_PROCESSES_H */
diff --git a/init/init.c b/init/init.c
index 05fce78..09b657b 100644
--- a/init/init.c
+++ b/init/init.c
@@ -1050,7 +1050,7 @@ start_child (const char *prog, char **progargs)
               NULL, 0, /* OSF Mach */
 #endif
               0, &child_task);
-  proc_child (procserver, child_task);
+  proc_set_init_task (procserver, child_task);
   proc_task2pid (procserver, child_task, &child_pid);
   proc_task2proc (procserver, child_task, &default_ports[INIT_PORT_PROC]);
 
diff --git a/proc/main.c b/proc/main.c
index 73abbc0..6fe2330 100644
--- a/proc/main.c
+++ b/proc/main.c
@@ -1,5 +1,5 @@
 /* Initialization of the proc server
-   Copyright (C) 1993,94,95,96,97,99,2000,01 Free Software Foundation, Inc.
+   Copyright (C) 1993,94,95,96,97,99,2000,01,13 Free Software Foundation, Inc.
 
 This file is part of the GNU Hurd.
 
@@ -82,7 +82,12 @@ main (int argc, char **argv, char **envp)
   generic_port = ports_get_right (genport);
 
   /* Create the initial proc object for init (PID 1).  */
-  startup_proc = create_startup_proc ();
+  init_proc = create_init_proc ();
+
+  /* Create the startup proc object for /hurd/init (PID 2).  */
+  startup_proc = allocate_proc (MACH_PORT_NULL);
+  startup_proc->p_deadmsg = 1;
+  complete_proc (startup_proc, HURD_PID_STARTUP);
 
   /* Create our own proc object (we are PID 0).  */
   self_proc = allocate_proc (mach_task_self ());
diff --git a/proc/mgt.c b/proc/mgt.c
index 1a881d0..cea9a41 100644
--- a/proc/mgt.c
+++ b/proc/mgt.c
@@ -1,5 +1,6 @@
 /* Process management
-   Copyright (C) 1992,93,94,95,96,99,2000,01,02 Free Software Foundation, Inc.
+   Copyright (C) 1992,93,94,95,96,99,2000,01,02,13
+     Free Software Foundation, Inc.
 
 This file is part of the GNU Hurd.
 
@@ -184,7 +185,7 @@ S_proc_child (struct proc *parentp,
   /* Process hierarchy.  Remove from our current location
      and place us under our new parent.  Sanity check to make sure
      parent is currently init. */
-  assert (childp->p_parent == startup_proc);
+  assert (childp->p_parent == init_proc);
   if (childp->p_sib)
     childp->p_sib->p_prevsib = childp->p_prevsib;
   *childp->p_prevsib = childp->p_sib;
@@ -574,7 +575,7 @@ allocate_proc (task_t task)
 /* Allocate and initialize the proc structure for init (PID 1),
    the original parent of all other procs.  */
 struct proc *
-create_startup_proc (void)
+create_init_proc (void)
 {
   static const uid_t zero;
   struct proc *p;
@@ -583,7 +584,7 @@ create_startup_proc (void)
   p = allocate_proc (MACH_PORT_NULL);
   assert (p);
 
-  p->p_pid = HURD_PID_STARTUP;
+  p->p_pid = HURD_PID_INIT;
 
   p->p_parent = p;
   p->p_sib = 0;
@@ -629,7 +630,7 @@ proc_death_notify (struct proc *p)
 }
 
 /* Complete a new process that has been allocated but not entirely initialized.
-   This gets called for every process except startup_proc (PID 1).  */
+   This gets called for every process except init_proc (PID 1).  */
 void
 complete_proc (struct proc *p, pid_t pid)
 {
@@ -648,30 +649,47 @@ complete_proc (struct proc *p, pid_t pid)
 
   p->p_pid = pid;
 
-  ids_ref (&nullids);
-  p->p_id = &nullids;
+  if (pid == HURD_PID_STARTUP)
+    {
+      /* Equip HURD_PID_STARTUP with the same credentials as
+         HURD_PID_INIT.  */
+      static const uid_t zero;
+      p->p_id = make_ids (&zero, 1);
+      assert (p->p_id);
+    }
+  else
+    {
+      ids_ref (&nullids);
+      p->p_id = &nullids;
+    }
 
   p->p_login = nulllogin;
   p->p_login->l_refcnt++;
 
   /* Our parent is init for now.  */
-  p->p_parent = startup_proc;
+  p->p_parent = init_proc;
 
-  p->p_sib = startup_proc->p_ochild;
-  p->p_prevsib = &startup_proc->p_ochild;
+  p->p_sib = init_proc->p_ochild;
+  p->p_prevsib = &init_proc->p_ochild;
   if (p->p_sib)
     p->p_sib->p_prevsib = &p->p_sib;
-  startup_proc->p_ochild = p;
+  init_proc->p_ochild = p;
   p->p_loginleader = 0;
   p->p_ochild = 0;
   p->p_parentset = 0;
 
   p->p_noowner = 1;
 
-  p->p_pgrp = startup_proc->p_pgrp;
+  p->p_pgrp = init_proc->p_pgrp;
 
-  proc_death_notify (p);
-  add_proc_to_hash (p);
+  /* At this point, we do not know the task of the startup process,
+     defer registering death notifications and adding it to the hash
+     tables.  */
+  if (pid != HURD_PID_STARTUP)
+    {
+      proc_death_notify (p);
+      add_proc_to_hash (p);
+    }
   join_pgrp (p);
 }
 
@@ -733,7 +751,7 @@ process_has_exited (struct proc *p)
            nowait_msg_proc_newids (tp->p_msgport, tp->p_task,
                                    1, tp->p_pgrp->pg_pgid,
                                    !tp->p_pgrp->pg_orphcnt);
-         tp->p_parent = startup_proc;
+         tp->p_parent = init_proc;
          if (tp->p_dead)
            isdead = 1;
        }
@@ -741,17 +759,17 @@ process_has_exited (struct proc *p)
        nowait_msg_proc_newids (tp->p_msgport, tp->p_task,
                                1, tp->p_pgrp->pg_pgid,
                                !tp->p_pgrp->pg_orphcnt);
-      tp->p_parent = startup_proc;
+      tp->p_parent = init_proc;
 
       /* And now append the lists. */
-      tp->p_sib = startup_proc->p_ochild;
+      tp->p_sib = init_proc->p_ochild;
       if (tp->p_sib)
        tp->p_sib->p_prevsib = &tp->p_sib;
-      startup_proc->p_ochild = p->p_ochild;
-      p->p_ochild->p_prevsib = &startup_proc->p_ochild;
+      init_proc->p_ochild = p->p_ochild;
+      p->p_ochild->p_prevsib = &init_proc->p_ochild;
 
       if (isdead)
-       alert_parent (startup_proc);
+       alert_parent (init_proc);
     }
 
   /* If an operation is in progress for this process, cause it
@@ -868,3 +886,21 @@ genpid ()
 
   return nextpid++;
 }
+
+/* Implement proc_set_init_task as described in <hurd/process.defs>.  */
+error_t
+S_proc_set_init_task(struct proc *callerp,
+                    task_t task)
+{
+  if (! callerp)
+    return EOPNOTSUPP;
+
+  if (callerp != startup_proc)
+    return EPERM;
+
+  init_proc->p_task = task;
+  proc_death_notify (init_proc);
+  add_proc_to_hash (init_proc);
+
+  return 0;
+}
diff --git a/proc/proc.h b/proc/proc.h
index 247795d..368b743 100644
--- a/proc/proc.h
+++ b/proc/proc.h
@@ -1,5 +1,6 @@
 /* Process server definitions
-   Copyright (C) 1992,93,94,95,96,99,2000,01 Free Software Foundation, Inc.
+   Copyright (C) 1992,93,94,95,96,99,2000,01,13
+     Free Software Foundation, Inc.
 
 This file is part of the GNU Hurd.
 
@@ -133,7 +134,8 @@ struct zombie *zombie_list;
 
 mach_port_t authserver;
 struct proc *self_proc;                /* process 0 (us) */
-struct proc *startup_proc;     /* process 1 (init) */
+struct proc *init_proc;                /* process 1 (sysvinit) */
+struct proc *startup_proc;     /* process 2 (hurd/init) */
 
 struct port_bucket *proc_bucket;
 struct port_class *proc_class;
@@ -193,7 +195,7 @@ void exc_clean (void *);
 struct proc *add_tasks (task_t);
 int pidfree (pid_t);
 
-struct proc *create_startup_proc (void);
+struct proc *create_init_proc (void);
 struct proc *allocate_proc (task_t);
 void proc_death_notify (struct proc *);
 void complete_proc (struct proc *, pid_t);
-- 
1.7.10.4