xref: /freebsd/sys/kern/init_main.c (revision 6780ab54325a71e7e70112b11657973edde8655e)
1 /*
2  * Copyright (c) 1995 Terrence R. Lambert
3  * All rights reserved.
4  *
5  * Copyright (c) 1982, 1986, 1989, 1991, 1992, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  * (c) UNIX System Laboratories, Inc.
8  * All or some portions of this file are derived from material licensed
9  * to the University of California by American Telephone and Telegraph
10  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
11  * the permission of UNIX System Laboratories, Inc.
12  *
13  * Redistribution and use in source and binary forms, with or without
14  * modification, are permitted provided that the following conditions
15  * are met:
16  * 1. Redistributions of source code must retain the above copyright
17  *    notice, this list of conditions and the following disclaimer.
18  * 2. Redistributions in binary form must reproduce the above copyright
19  *    notice, this list of conditions and the following disclaimer in the
20  *    documentation and/or other materials provided with the distribution.
21  * 3. All advertising materials mentioning features or use of this software
22  *    must display the following acknowledgement:
23  *	This product includes software developed by the University of
24  *	California, Berkeley and its contributors.
25  * 4. Neither the name of the University nor the names of its contributors
26  *    may be used to endorse or promote products derived from this software
27  *    without specific prior written permission.
28  *
29  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
30  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
31  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
32  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
33  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
34  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
35  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
36  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
37  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
38  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
39  * SUCH DAMAGE.
40  *
41  *	@(#)init_main.c	8.9 (Berkeley) 1/21/94
42  * $FreeBSD$
43  */
44 
45 #include "opt_init_path.h"
46 #include "opt_mac.h"
47 
48 #include <sys/param.h>
49 #include <sys/kernel.h>
50 #include <sys/exec.h>
51 #include <sys/file.h>
52 #include <sys/filedesc.h>
53 #include <sys/ktr.h>
54 #include <sys/lock.h>
55 #include <sys/mac.h>
56 #include <sys/mount.h>
57 #include <sys/mutex.h>
58 #include <sys/syscallsubr.h>
59 #include <sys/sysctl.h>
60 #include <sys/proc.h>
61 #include <sys/resourcevar.h>
62 #include <sys/systm.h>
63 #include <sys/signalvar.h>
64 #include <sys/vnode.h>
65 #include <sys/sysent.h>
66 #include <sys/reboot.h>
67 #include <sys/sched.h>
68 #include <sys/sx.h>
69 #include <sys/sysproto.h>
70 #include <sys/vmmeter.h>
71 #include <sys/unistd.h>
72 #include <sys/malloc.h>
73 #include <sys/conf.h>
74 
75 #include <machine/cpu.h>
76 
77 #include <vm/vm.h>
78 #include <vm/vm_param.h>
79 #include <vm/pmap.h>
80 #include <vm/vm_map.h>
81 #include <sys/user.h>
82 #include <sys/copyright.h>
83 
84 void mi_startup(void);				/* Should be elsewhere */
85 
86 /* Components of the first process -- never freed. */
87 static struct session session0;
88 static struct pgrp pgrp0;
89 struct	proc proc0;
90 struct	thread thread0;
91 struct	kse kse0;
92 struct	ksegrp ksegrp0;
93 static struct procsig procsig0;
94 static struct filedesc0 filedesc0;
95 static struct plimit limit0;
96 static struct vmspace vmspace0;
97 struct	proc *initproc;
98 
99 int cmask = CMASK;
100 
101 struct	vnode *rootvp;
102 int	boothowto = 0;		/* initialized so that it can be patched */
103 SYSCTL_INT(_debug, OID_AUTO, boothowto, CTLFLAG_RD, &boothowto, 0, "");
104 int	bootverbose;
105 SYSCTL_INT(_debug, OID_AUTO, bootverbose, CTLFLAG_RW, &bootverbose, 0, "");
106 
107 /*
108  * This ensures that there is at least one entry so that the sysinit_set
109  * symbol is not undefined.  A sybsystem ID of SI_SUB_DUMMY is never
110  * executed.
111  */
112 SYSINIT(placeholder, SI_SUB_DUMMY, SI_ORDER_ANY, NULL, NULL)
113 
114 /*
115  * The sysinit table itself.  Items are checked off as the are run.
116  * If we want to register new sysinit types, add them to newsysinit.
117  */
118 SET_DECLARE(sysinit_set, struct sysinit);
119 struct sysinit **sysinit, **sysinit_end;
120 struct sysinit **newsysinit, **newsysinit_end;
121 
122 /*
123  * Merge a new sysinit set into the current set, reallocating it if
124  * necessary.  This can only be called after malloc is running.
125  */
126 void
127 sysinit_add(struct sysinit **set, struct sysinit **set_end)
128 {
129 	struct sysinit **newset;
130 	struct sysinit **sipp;
131 	struct sysinit **xipp;
132 	int count;
133 
134 	count = set_end - set;
135 	if (newsysinit)
136 		count += newsysinit_end - newsysinit;
137 	else
138 		count += sysinit_end - sysinit;
139 	newset = malloc(count * sizeof(*sipp), M_TEMP, M_NOWAIT);
140 	if (newset == NULL)
141 		panic("cannot malloc for sysinit");
142 	xipp = newset;
143 	if (newsysinit)
144 		for (sipp = newsysinit; sipp < newsysinit_end; sipp++)
145 			*xipp++ = *sipp;
146 	else
147 		for (sipp = sysinit; sipp < sysinit_end; sipp++)
148 			*xipp++ = *sipp;
149 	for (sipp = set; sipp < set_end; sipp++)
150 		*xipp++ = *sipp;
151 	if (newsysinit)
152 		free(newsysinit, M_TEMP);
153 	newsysinit = newset;
154 	newsysinit_end = newset + count;
155 }
156 
157 /*
158  * System startup; initialize the world, create process 0, mount root
159  * filesystem, and fork to create init and pagedaemon.  Most of the
160  * hard work is done in the lower-level initialization routines including
161  * startup(), which does memory initialization and autoconfiguration.
162  *
163  * This allows simple addition of new kernel subsystems that require
164  * boot time initialization.  It also allows substitution of subsystem
165  * (for instance, a scheduler, kernel profiler, or VM system) by object
166  * module.  Finally, it allows for optional "kernel threads".
167  */
168 void
169 mi_startup(void)
170 {
171 
172 	register struct sysinit **sipp;		/* system initialization*/
173 	register struct sysinit **xipp;		/* interior loop of sort*/
174 	register struct sysinit *save;		/* bubble*/
175 
176 	if (sysinit == NULL) {
177 		sysinit = SET_BEGIN(sysinit_set);
178 		sysinit_end = SET_LIMIT(sysinit_set);
179 	}
180 
181 restart:
182 	/*
183 	 * Perform a bubble sort of the system initialization objects by
184 	 * their subsystem (primary key) and order (secondary key).
185 	 */
186 	for (sipp = sysinit; sipp < sysinit_end; sipp++) {
187 		for (xipp = sipp + 1; xipp < sysinit_end; xipp++) {
188 			if ((*sipp)->subsystem < (*xipp)->subsystem ||
189 			     ((*sipp)->subsystem == (*xipp)->subsystem &&
190 			      (*sipp)->order <= (*xipp)->order))
191 				continue;	/* skip*/
192 			save = *sipp;
193 			*sipp = *xipp;
194 			*xipp = save;
195 		}
196 	}
197 
198 	/*
199 	 * Traverse the (now) ordered list of system initialization tasks.
200 	 * Perform each task, and continue on to the next task.
201 	 *
202 	 * The last item on the list is expected to be the scheduler,
203 	 * which will not return.
204 	 */
205 	for (sipp = sysinit; sipp < sysinit_end; sipp++) {
206 
207 		if ((*sipp)->subsystem == SI_SUB_DUMMY)
208 			continue;	/* skip dummy task(s)*/
209 
210 		if ((*sipp)->subsystem == SI_SUB_DONE)
211 			continue;
212 
213 		/* Call function */
214 		(*((*sipp)->func))((*sipp)->udata);
215 
216 		/* Check off the one we're just done */
217 		(*sipp)->subsystem = SI_SUB_DONE;
218 
219 		/* Check if we've installed more sysinit items via KLD */
220 		if (newsysinit != NULL) {
221 			if (sysinit != SET_BEGIN(sysinit_set))
222 				free(sysinit, M_TEMP);
223 			sysinit = newsysinit;
224 			sysinit_end = newsysinit_end;
225 			newsysinit = NULL;
226 			newsysinit_end = NULL;
227 			goto restart;
228 		}
229 	}
230 
231 	panic("Shouldn't get here!");
232 	/* NOTREACHED*/
233 }
234 
235 
236 /*
237  ***************************************************************************
238  ****
239  **** The following SYSINIT's belong elsewhere, but have not yet
240  **** been moved.
241  ****
242  ***************************************************************************
243  */
244 static void
245 print_caddr_t(void *data __unused)
246 {
247 	printf("%s", (char *)data);
248 }
249 SYSINIT(announce, SI_SUB_COPYRIGHT, SI_ORDER_FIRST, print_caddr_t, copyright)
250 SYSINIT(version, SI_SUB_COPYRIGHT, SI_ORDER_SECOND, print_caddr_t, version)
251 
252 static void
253 set_boot_verbose(void *data __unused)
254 {
255 
256 	if (boothowto & RB_VERBOSE)
257 		bootverbose++;
258 }
259 SYSINIT(boot_verbose, SI_SUB_TUNABLES, SI_ORDER_ANY, set_boot_verbose, NULL)
260 
261 struct sysentvec null_sysvec = {
262 	0,
263 	NULL,
264 	0,
265 	0,
266 	NULL,
267 	0,
268 	NULL,
269 	NULL,
270 	NULL,
271 	NULL,
272 	NULL,
273 	NULL,
274 	NULL,
275 	"null",
276 	NULL,
277 	NULL,
278 	0,
279 	PAGE_SIZE,
280 	VM_MIN_ADDRESS,
281 	VM_MAXUSER_ADDRESS,
282 	USRSTACK,
283 	PS_STRINGS,
284 	VM_PROT_ALL,
285 	NULL,
286 	NULL
287 };
288 
289 /*
290  ***************************************************************************
291  ****
292  **** The two following SYSINIT's are proc0 specific glue code.  I am not
293  **** convinced that they can not be safely combined, but their order of
294  **** operation has been maintained as the same as the original init_main.c
295  **** for right now.
296  ****
297  **** These probably belong in init_proc.c or kern_proc.c, since they
298  **** deal with proc0 (the fork template process).
299  ****
300  ***************************************************************************
301  */
302 /* ARGSUSED*/
303 static void
304 proc0_init(void *dummy __unused)
305 {
306 	register struct proc		*p;
307 	register struct filedesc0	*fdp;
308 	register unsigned i;
309 	struct thread *td;
310 	struct ksegrp *kg;
311 	struct kse *ke;
312 
313 	GIANT_REQUIRED;
314 	p = &proc0;
315 	td = &thread0;
316 	ke = &kse0;
317 	kg = &ksegrp0;
318 
319 	ke->ke_sched = kse0_sched;
320 	kg->kg_sched = ksegrp0_sched;
321 	p->p_sched = proc0_sched;
322 	td->td_sched = thread0_sched;
323 
324 	/*
325 	 * Initialize magic number.
326 	 */
327 	p->p_magic = P_MAGIC;
328 
329 	/*
330 	 * Initialize thread, process and pgrp structures.
331 	 */
332 	procinit();
333 	threadinit();
334 
335 	/*
336 	 * Initialize sleep queue hash table
337 	 */
338 	sleepinit();
339 
340 	/*
341 	 * additional VM structures
342 	 */
343 	vm_init2();
344 
345 	/*
346 	 * Create process 0 (the swapper).
347 	 */
348 	LIST_INSERT_HEAD(&allproc, p, p_list);
349 	LIST_INSERT_HEAD(PIDHASH(0), p, p_hash);
350 	mtx_init(&pgrp0.pg_mtx, "process group", NULL, MTX_DEF | MTX_DUPOK);
351 	p->p_pgrp = &pgrp0;
352 	LIST_INSERT_HEAD(PGRPHASH(0), &pgrp0, pg_hash);
353 	LIST_INIT(&pgrp0.pg_members);
354 	LIST_INSERT_HEAD(&pgrp0.pg_members, p, p_pglist);
355 
356 	pgrp0.pg_session = &session0;
357 	mtx_init(&session0.s_mtx, "session", NULL, MTX_DEF);
358 	session0.s_count = 1;
359 	session0.s_leader = p;
360 
361 	p->p_sysent = &null_sysvec;
362 
363 	/*
364 	 * proc_linkup was already done in init_i386() or alphainit() etc.
365 	 * because the earlier code needed to follow td->td_proc. Otherwise
366 	 * I would have done it here.. maybe this means this should be
367 	 * done earlier too.
368 	 */
369 	p->p_flag = P_SYSTEM;
370 	p->p_sflag = PS_INMEM;
371 	p->p_state = PRS_NORMAL;
372 	td->td_state = TDS_RUNNING;
373 	kg->kg_nice = NZERO;
374 	kg->kg_pri_class = PRI_TIMESHARE;
375 	kg->kg_user_pri = PUSER;
376 	td->td_priority = PVM;
377 	td->td_base_pri = PUSER;
378 	td->td_kse = ke; /* XXXKSE */
379 	ke->ke_oncpu = 0;
380 	ke->ke_state = KES_THREAD;
381 	ke->ke_thread = td;
382 	ke->ke_owner = td;
383 	p->p_peers = 0;
384 	p->p_leader = p;
385 
386 
387 	bcopy("swapper", p->p_comm, sizeof ("swapper"));
388 
389 	callout_init(&p->p_itcallout, 0);
390 	callout_init(&td->td_slpcallout, 1);
391 
392 	/* Create credentials. */
393 	p->p_ucred = crget();
394 	p->p_ucred->cr_ngroups = 1;	/* group 0 */
395 	p->p_ucred->cr_uidinfo = uifind(0);
396 	p->p_ucred->cr_ruidinfo = uifind(0);
397 	p->p_ucred->cr_prison = NULL;	/* Don't jail it. */
398 #ifdef MAC
399 	mac_create_proc0(p->p_ucred);
400 #endif
401 	td->td_ucred = crhold(p->p_ucred);
402 
403 	/* Create procsig. */
404 	p->p_procsig = &procsig0;
405 	p->p_procsig->ps_refcnt = 1;
406 
407 	/* Initialize signal state for process 0. */
408 	siginit(&proc0);
409 
410 	/* Create the file descriptor table. */
411 	fdp = &filedesc0;
412 	p->p_fd = &fdp->fd_fd;
413 	mtx_init(&fdp->fd_fd.fd_mtx, FILEDESC_LOCK_DESC, NULL, MTX_DEF);
414 	fdp->fd_fd.fd_refcnt = 1;
415 	fdp->fd_fd.fd_cmask = cmask;
416 	fdp->fd_fd.fd_ofiles = fdp->fd_dfiles;
417 	fdp->fd_fd.fd_ofileflags = fdp->fd_dfileflags;
418 	fdp->fd_fd.fd_nfiles = NDFILE;
419 
420 	/* Create the limits structures. */
421 	p->p_limit = &limit0;
422 	for (i = 0; i < sizeof(p->p_rlimit)/sizeof(p->p_rlimit[0]); i++)
423 		limit0.pl_rlimit[i].rlim_cur =
424 		    limit0.pl_rlimit[i].rlim_max = RLIM_INFINITY;
425 	limit0.pl_rlimit[RLIMIT_NOFILE].rlim_cur =
426 	    limit0.pl_rlimit[RLIMIT_NOFILE].rlim_max = maxfiles;
427 	limit0.pl_rlimit[RLIMIT_NPROC].rlim_cur =
428 	    limit0.pl_rlimit[RLIMIT_NPROC].rlim_max = maxproc;
429 	i = ptoa(cnt.v_free_count);
430 	limit0.pl_rlimit[RLIMIT_RSS].rlim_max = i;
431 	limit0.pl_rlimit[RLIMIT_MEMLOCK].rlim_max = i;
432 	limit0.pl_rlimit[RLIMIT_MEMLOCK].rlim_cur = i / 3;
433 	limit0.p_refcnt = 1;
434 	p->p_cpulimit = RLIM_INFINITY;
435 
436 	/* Allocate a prototype map so we have something to fork. */
437 	pmap_pinit0(vmspace_pmap(&vmspace0));
438 	p->p_vmspace = &vmspace0;
439 	vmspace0.vm_refcnt = 1;
440 	vm_map_init(&vmspace0.vm_map, p->p_sysent->sv_minuser,
441 	    p->p_sysent->sv_maxuser);
442 	vmspace0.vm_map.pmap = vmspace_pmap(&vmspace0);
443 
444 	/*
445 	 * We continue to place resource usage info and signal
446 	 * actions in the user struct so they're pageable.
447 	 */
448 	p->p_stats = &p->p_uarea->u_stats;
449 	p->p_sigacts = &p->p_uarea->u_sigacts;
450 
451 	/*
452 	 * Charge root for one process.
453 	 */
454 	(void)chgproccnt(p->p_ucred->cr_ruidinfo, 1, 0);
455 }
456 SYSINIT(p0init, SI_SUB_INTRINSIC, SI_ORDER_FIRST, proc0_init, NULL)
457 
458 /* ARGSUSED*/
459 static void
460 proc0_post(void *dummy __unused)
461 {
462 	struct timespec ts;
463 	struct proc *p;
464 
465 	/*
466 	 * Now we can look at the time, having had a chance to verify the
467 	 * time from the filesystem.  Pretend that proc0 started now.
468 	 */
469 	sx_slock(&allproc_lock);
470 	LIST_FOREACH(p, &allproc, p_list) {
471 		microtime(&p->p_stats->p_start);
472 		p->p_runtime.sec = 0;
473 		p->p_runtime.frac = 0;
474 	}
475 	sx_sunlock(&allproc_lock);
476 	binuptime(PCPU_PTR(switchtime));
477 	PCPU_SET(switchticks, ticks);
478 
479 	/*
480 	 * Give the ``random'' number generator a thump.
481 	 */
482 	nanotime(&ts);
483 	srandom(ts.tv_sec ^ ts.tv_nsec);
484 }
485 SYSINIT(p0post, SI_SUB_INTRINSIC_POST, SI_ORDER_FIRST, proc0_post, NULL)
486 
487 /*
488  ***************************************************************************
489  ****
490  **** The following SYSINIT's and glue code should be moved to the
491  **** respective files on a per subsystem basis.
492  ****
493  ***************************************************************************
494  */
495 
496 
497 /*
498  ***************************************************************************
499  ****
500  **** The following code probably belongs in another file, like
501  **** kern/init_init.c.
502  ****
503  ***************************************************************************
504  */
505 
506 /*
507  * List of paths to try when searching for "init".
508  */
509 static char init_path[MAXPATHLEN] =
510 #ifdef	INIT_PATH
511     __XSTRING(INIT_PATH);
512 #else
513     "/sbin/init:/sbin/oinit:/sbin/init.bak:/stand/sysinstall";
514 #endif
515 SYSCTL_STRING(_kern, OID_AUTO, init_path, CTLFLAG_RD, init_path, 0,
516 	"Path used to search the init process");
517 
518 /*
519  * Start the initial user process; try exec'ing each pathname in init_path.
520  * The program is invoked with one argument containing the boot flags.
521  */
522 static void
523 start_init(void *dummy)
524 {
525 	vm_offset_t addr;
526 	struct execve_args args;
527 	int options, error;
528 	char *var, *path, *next, *s;
529 	char *ucp, **uap, *arg0, *arg1;
530 	struct thread *td;
531 	struct proc *p;
532 	int init_does_devfs = 0;
533 
534 	mtx_lock(&Giant);
535 
536 	GIANT_REQUIRED;
537 
538 	td = curthread;
539 	p = td->td_proc;
540 
541 	vfs_mountroot();
542 
543 	/* Get the vnode for '/'.  Set p->p_fd->fd_cdir to reference it. */
544 	if (VFS_ROOT(TAILQ_FIRST(&mountlist), &rootvnode))
545 		panic("cannot find root vnode");
546 	FILEDESC_LOCK(p->p_fd);
547 	p->p_fd->fd_cdir = rootvnode;
548 	VREF(p->p_fd->fd_cdir);
549 	p->p_fd->fd_rdir = rootvnode;
550 	VREF(p->p_fd->fd_rdir);
551 	FILEDESC_UNLOCK(p->p_fd);
552 	VOP_UNLOCK(rootvnode, 0, td);
553 #ifdef MAC
554 	mac_create_root_mount(td->td_ucred, TAILQ_FIRST(&mountlist));
555 #endif
556 
557 	/*
558 	 * For disk based systems, we probably cannot do this yet
559 	 * since the fs will be read-only.  But a NFS root
560 	 * might be ok.  It is worth a shot.
561 	 */
562 	error = kern_mkdir(td, "/dev", UIO_SYSSPACE, 0700);
563 	if (error == EEXIST)
564 		error = 0;
565 	if (error == 0)
566 		error = kernel_vmount(0, "fstype", "devfs",
567 		    "fspath", "/dev", NULL);
568 	if (error != 0)
569 		init_does_devfs = 1;
570 
571 	/*
572 	 * Need just enough stack to hold the faked-up "execve()" arguments.
573 	 */
574 	addr = p->p_sysent->sv_usrstack - PAGE_SIZE;
575 	if (vm_map_find(&p->p_vmspace->vm_map, NULL, 0, &addr, PAGE_SIZE,
576 			FALSE, VM_PROT_ALL, VM_PROT_ALL, 0) != 0)
577 		panic("init: couldn't allocate argument space");
578 	p->p_vmspace->vm_maxsaddr = (caddr_t)addr;
579 	p->p_vmspace->vm_ssize = 1;
580 
581 	if ((var = getenv("init_path")) != NULL) {
582 		strlcpy(init_path, var, sizeof(init_path));
583 		freeenv(var);
584 	}
585 
586 	printf("Be nice to each other, mmmkay?\n");
587 
588 	for (path = init_path; *path != '\0'; path = next) {
589 		while (*path == ':')
590 			path++;
591 		if (*path == '\0')
592 			break;
593 		for (next = path; *next != '\0' && *next != ':'; next++)
594 			/* nothing */ ;
595 		if (bootverbose)
596 			printf("start_init: trying %.*s\n", (int)(next - path),
597 			    path);
598 
599 		/*
600 		 * Move out the boot flag argument.
601 		 */
602 		options = 0;
603 		ucp = (char *)p->p_sysent->sv_usrstack;
604 		(void)subyte(--ucp, 0);		/* trailing zero */
605 		if (boothowto & RB_SINGLE) {
606 			(void)subyte(--ucp, 's');
607 			options = 1;
608 		}
609 #ifdef notyet
610                 if (boothowto & RB_FASTBOOT) {
611 			(void)subyte(--ucp, 'f');
612 			options = 1;
613 		}
614 #endif
615 
616 #ifdef BOOTCDROM
617 		(void)subyte(--ucp, 'C');
618 		options = 1;
619 #endif
620 		if (init_does_devfs) {
621 			(void)subyte(--ucp, 'd');
622 			options = 1;
623 		}
624 
625 		if (options == 0)
626 			(void)subyte(--ucp, '-');
627 		(void)subyte(--ucp, '-');		/* leading hyphen */
628 		arg1 = ucp;
629 
630 		/*
631 		 * Move out the file name (also arg 0).
632 		 */
633 		(void)subyte(--ucp, 0);
634 		for (s = next - 1; s >= path; s--)
635 			(void)subyte(--ucp, *s);
636 		arg0 = ucp;
637 
638 		/*
639 		 * Move out the arg pointers.
640 		 */
641 		uap = (char **)((intptr_t)ucp & ~(sizeof(intptr_t)-1));
642 		(void)suword((caddr_t)--uap, (long)0);	/* terminator */
643 		(void)suword((caddr_t)--uap, (long)(intptr_t)arg1);
644 		(void)suword((caddr_t)--uap, (long)(intptr_t)arg0);
645 
646 		/*
647 		 * Point at the arguments.
648 		 */
649 		args.fname = arg0;
650 		args.argv = uap;
651 		args.envv = NULL;
652 
653 		/*
654 		 * Now try to exec the program.  If can't for any reason
655 		 * other than it doesn't exist, complain.
656 		 *
657 		 * Otherwise, return via fork_trampoline() all the way
658 		 * to user mode as init!
659 		 */
660 		if ((error = execve(td, &args)) == 0) {
661 			mtx_unlock(&Giant);
662 			return;
663 		}
664 		if (error != ENOENT)
665 			printf("exec %.*s: error %d\n", (int)(next - path),
666 			    path, error);
667 	}
668 	printf("init: not found in path %s\n", init_path);
669 	panic("no init");
670 }
671 
672 /*
673  * Like kthread_create(), but runs in it's own address space.
674  * We do this early to reserve pid 1.
675  *
676  * Note special case - do not make it runnable yet.  Other work
677  * in progress will change this more.
678  */
679 static void
680 create_init(const void *udata __unused)
681 {
682 	struct ucred *newcred, *oldcred;
683 	int error;
684 
685 	error = fork1(&thread0, RFFDG | RFPROC | RFSTOPPED, 0, &initproc);
686 	if (error)
687 		panic("cannot fork init: %d\n", error);
688 	/* divorce init's credentials from the kernel's */
689 	newcred = crget();
690 	PROC_LOCK(initproc);
691 	initproc->p_flag |= P_SYSTEM;
692 	oldcred = initproc->p_ucred;
693 	crcopy(newcred, oldcred);
694 #ifdef MAC
695 	mac_create_proc1(newcred);
696 #endif
697 	initproc->p_ucred = newcred;
698 	PROC_UNLOCK(initproc);
699 	crfree(oldcred);
700 	cred_update_thread(FIRST_THREAD_IN_PROC(initproc));
701 	mtx_lock_spin(&sched_lock);
702 	initproc->p_sflag |= PS_INMEM;
703 	mtx_unlock_spin(&sched_lock);
704 	cpu_set_fork_handler(FIRST_THREAD_IN_PROC(initproc), start_init, NULL);
705 }
706 SYSINIT(init, SI_SUB_CREATE_INIT, SI_ORDER_FIRST, create_init, NULL)
707 
708 /*
709  * Make it runnable now.
710  */
711 static void
712 kick_init(const void *udata __unused)
713 {
714 	struct thread *td;
715 
716 	td = FIRST_THREAD_IN_PROC(initproc);
717 	mtx_lock_spin(&sched_lock);
718 	TD_SET_CAN_RUN(td);
719 	setrunqueue(td);	/* XXXKSE */
720 	mtx_unlock_spin(&sched_lock);
721 }
722 SYSINIT(kickinit, SI_SUB_KTHREAD_INIT, SI_ORDER_FIRST, kick_init, NULL)
723