Pass the kernel's task port to proc.

Previously, the early server bootstrap relied upon a specific task
layout to determine the kernels task port.  Explicitly pass it from
the kernel instead.

* boot/boot.c (default_boot_script): Add '--kernel-task' parameter to
ext2fs.
(main): New bootscript variable 'kernel-task'.
* libdiskfs/boot-start.c (diskfs_kernel_task): Declaration variable.
(diskfs_start_bootstrap): If '--kernel-task' was given to us, pass it
along to startup.
* libdiskfs/opts-std-startup.c (diskfs_kernel_task): New variable.
(startup_options): Add '--kernel-task' option.
(parse_startup_opt): Handle option.
* proc/main.c (kernel_task): New variable.
(OPT_KERNEL_TASK): New macro.
(options): New variable.
(parse_opt): New function.
(main): Parse options.  Use 'kernel_task' if provided.
* release/servers.boot: Add '--kernel-task' parameter to ext2fs.
* startup/startup.c (OPT_KERNEL_TASK): New macro.
(options): Add '--kernel-task' option.
(kernel_task): New variable.
(insert_ports_fnc_t): New declaration.
(run): Add argument for a function that inserts rights into the newly
created task and adds arguments to the argument vector.
(argz_task_insert_right): New function.
(proc_insert_ports): Likewise.
(parse_opt): New function.
(main): Pass the kernel's task port to proc.
(frob_kernel_process): Use the kernel's task port.

2 files changed, 39 insertions, 10 deletions

diff --git a/libdiskfs/boot-start.c b/libdiskfs/boot-start.c
index 0fb3e89d..f048badf 100644
--- a/libdiskfs/boot-start.c
+++ b/libdiskfs/boot-start.c
@@ -40,6 +40,7 @@
 
 static mach_port_t diskfs_exec_ctl;
 extern task_t diskfs_exec_server_task;
+extern task_t diskfs_kernel_task;
 static task_t parent_task = MACH_PORT_NULL;
 
 static pthread_mutex_t execstartlock;
@@ -206,9 +207,6 @@ diskfs_start_bootstrap ()
       /* We have a boot command line to run instead of init.  */
       err = argz_create (_diskfs_boot_command, &exec_argv, &exec_argvlen);
       assert_perror (err);
-      initname = exec_argv;
-      while (*initname == '/')
-	initname++;
     }
   else
     {
@@ -223,10 +221,42 @@ diskfs_start_bootstrap ()
       err = argz_add_sep (&exec_argv, &exec_argvlen,
 			  diskfs_boot_command_line, ' ');
       assert_perror (err);
+    }
+
+  err = task_create (mach_task_self (),
+#ifdef KERN_INVALID_LEDGER
+		     NULL, 0,	/* OSF Mach */
+#endif
+		     0, &newt);
+  assert_perror (err);
 
-      initname = exec_argv + 1;
+  if (MACH_PORT_VALID (diskfs_kernel_task))
+    {
+      mach_port_t kernel_task_name = MACH_PORT_NULL;
+      char buf[20];
+      int len;
+
+      do
+        {
+          kernel_task_name += 1;
+          err = mach_port_insert_right (newt, kernel_task_name,
+                                        diskfs_kernel_task, MACH_MSG_TYPE_MOVE_SEND);
+        }
+      while (err == KERN_NAME_EXISTS);
+      diskfs_kernel_task = MACH_PORT_NULL;
+
+      len = snprintf (buf, sizeof buf, "--kernel-task=%d", kernel_task_name);
+      assert (len < sizeof buf);
+      /* Insert as second argument.  */
+      err = argz_insert (&exec_argv, &exec_argvlen,
+                         argz_next (exec_argv, exec_argvlen, exec_argv), buf);
+      assert_perror (err);
     }
 
+  initname = exec_argv;
+  while (*initname == '/')
+    initname++;
+
  lookup_init:
   err = dir_lookup (root_pt, (char *) initname, O_READ, 0, &retry, pathbuf,
                     &startup_pt);
@@ -270,12 +300,6 @@ diskfs_start_bootstrap ()
   err = argz_create (environ, &exec_env, &exec_envlen);
   assert_perror (err);
 
-  err = task_create (mach_task_self (),
-#ifdef KERN_INVALID_LEDGER
-		     NULL, 0,	/* OSF Mach */
-#endif
-		     0, &newt);
-  assert_perror (err);
   if (_diskfs_boot_pause)
     {
       printf ("pausing for %s...\n", exec_argv);
diff --git a/libdiskfs/opts-std-startup.c b/libdiskfs/opts-std-startup.c
index ed25a18d..a38db99a 100644
--- a/libdiskfs/opts-std-startup.c
+++ b/libdiskfs/opts-std-startup.c
@@ -35,6 +35,7 @@ int _diskfs_boot_pause;
 extern char **diskfs_argv;
 
 mach_port_t diskfs_exec_server_task = MACH_PORT_NULL;
+mach_port_t diskfs_kernel_task = MACH_PORT_NULL;
 
 /* ---------------------------------------------------------------- */
 
@@ -45,6 +46,7 @@ mach_port_t diskfs_exec_server_task = MACH_PORT_NULL;
 #define OPT_BOOT_COMMAND	(-5)
 #define OPT_BOOT_INIT_PROGRAM	(-6)
 #define OPT_BOOT_PAUSE		(-7)
+#define OPT_KERNEL_TASK		(-8)
 
 static const struct argp_option
 startup_options[] =
@@ -68,6 +70,7 @@ startup_options[] =
   {"host-priv-port",     OPT_HOST_PRIV_PORT,     "PORT"},
   {"device-master-port", OPT_DEVICE_MASTER_PORT, "PORT"},
   {"exec-server-task",   OPT_EXEC_SERVER_TASK,   "PORT"},
+  {"kernel-task",        OPT_KERNEL_TASK,        "PORT"},
 
   {0}
 };
@@ -106,6 +109,8 @@ parse_startup_opt (int opt, char *arg, struct argp_state *state)
       _hurd_host_priv = atoi (arg); break;
     case OPT_EXEC_SERVER_TASK:
       diskfs_exec_server_task = atoi (arg); break;
+    case OPT_KERNEL_TASK:
+      diskfs_kernel_task = atoi (arg); break;
     case OPT_BOOT_CMDLINE:
       diskfs_boot_command_line = arg; break;
     case OPT_BOOT_INIT_PROGRAM: