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init_main.c revision 1.169
      1 /*	$NetBSD: init_main.c,v 1.169 2000/05/28 05:49:05 thorpej Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1995 Christopher G. Demetriou.  All rights reserved.
      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	8.16 (Berkeley) 5/14/95
     42  */
     43 
     44 #include "fs_nfs.h"
     45 #include "opt_nfsserver.h"
     46 #include "opt_sysv.h"
     47 #include "opt_maxuprc.h"
     48 #include "opt_multiprocessor.h"
     49 
     50 #include "rnd.h"
     51 
     52 #include <sys/param.h>
     53 #include <sys/acct.h>
     54 #include <sys/filedesc.h>
     55 #include <sys/file.h>
     56 #include <sys/errno.h>
     57 #include <sys/exec.h>
     58 #include <sys/callout.h>
     59 #include <sys/kernel.h>
     60 #include <sys/mount.h>
     61 #include <sys/map.h>
     62 #include <sys/proc.h>
     63 #include <sys/kthread.h>
     64 #include <sys/resourcevar.h>
     65 #include <sys/signalvar.h>
     66 #include <sys/systm.h>
     67 #include <sys/vnode.h>
     68 #include <sys/tty.h>
     69 #include <sys/conf.h>
     70 #include <sys/disklabel.h>
     71 #include <sys/buf.h>
     72 #include <sys/device.h>
     73 #include <sys/socketvar.h>
     74 #include <sys/protosw.h>
     75 #include <sys/reboot.h>
     76 #include <sys/user.h>
     77 #ifdef SYSVSHM
     78 #include <sys/shm.h>
     79 #endif
     80 #ifdef SYSVSEM
     81 #include <sys/sem.h>
     82 #endif
     83 #ifdef SYSVMSG
     84 #include <sys/msg.h>
     85 #endif
     86 #include <sys/domain.h>
     87 #include <sys/mbuf.h>
     88 #include <sys/namei.h>
     89 #if NRND > 0
     90 #include <sys/rnd.h>
     91 #endif
     92 
     93 #include <sys/syscall.h>
     94 #include <sys/syscallargs.h>
     95 
     96 #include <ufs/ufs/quota.h>
     97 
     98 #include <miscfs/genfs/genfs.h>
     99 #include <miscfs/syncfs/syncfs.h>
    100 
    101 #include <machine/cpu.h>
    102 
    103 #include <vm/vm.h>
    104 #include <vm/vm_pageout.h>
    105 
    106 #include <uvm/uvm.h>
    107 
    108 #include <net/if.h>
    109 #include <net/raw_cb.h>
    110 
    111 char	copyright[] = "\
    112 Copyright (c) 1996, 1997, 1998, 1999, 2000
    113     The NetBSD Foundation, Inc.  All rights reserved.
    114 Copyright (c) 1982, 1986, 1989, 1991, 1993
    115     The Regents of the University of California.  All rights reserved.
    116 
    117 ";
    118 
    119 /* Components of the first process -- never freed. */
    120 struct	session session0;
    121 struct	pgrp pgrp0;
    122 struct	proc proc0;
    123 struct	pcred cred0;
    124 struct	filedesc0 filedesc0;
    125 struct	cwdinfo cwdi0;
    126 struct	plimit limit0;
    127 struct	vmspace vmspace0;
    128 struct	sigacts sigacts0;
    129 #ifndef curproc
    130 struct	proc *curproc = &proc0;
    131 #endif
    132 struct	proc *initproc;
    133 
    134 int	cmask = CMASK;
    135 extern	struct user *proc0paddr;
    136 
    137 struct	vnode *rootvp, *swapdev_vp;
    138 int	boothowto;
    139 int	cold = 1;			/* still working on startup */
    140 struct	timeval boottime;
    141 
    142 __volatile int start_init_exec;		/* semaphore for start_init() */
    143 
    144 static void check_console __P((struct proc *p));
    145 static void start_init __P((void *));
    146 static void start_pagedaemon __P((void *));
    147 static void start_reaper __P((void *));
    148 void main __P((void));
    149 
    150 extern char sigcode[], esigcode[];
    151 #ifdef SYSCALL_DEBUG
    152 extern char *syscallnames[];
    153 #endif
    154 
    155 struct emul emul_netbsd = {
    156 	"netbsd",
    157 	NULL,
    158 	sendsig,
    159 	SYS_syscall,
    160 	SYS_MAXSYSCALL,
    161 	sysent,
    162 #ifdef SYSCALL_DEBUG
    163 	syscallnames,
    164 #else
    165 	NULL,
    166 #endif
    167 	0,
    168 	copyargs,
    169 	setregs,
    170 	sigcode,
    171 	esigcode,
    172 };
    173 
    174 /*
    175  * System startup; initialize the world, create process 0, mount root
    176  * filesystem, and fork to create init and pagedaemon.  Most of the
    177  * hard work is done in the lower-level initialization routines including
    178  * startup(), which does memory initialization and autoconfiguration.
    179  */
    180 void
    181 main()
    182 {
    183 	struct proc *p;
    184 	struct pdevinit *pdev;
    185 	int i, s, error;
    186 	extern struct pdevinit pdevinit[];
    187 	extern void roundrobin __P((void *));
    188 	extern void schedcpu __P((void *));
    189 	extern void disk_init __P((void));
    190 #if defined(NFSSERVER) || defined(NFS)
    191 	extern void nfs_init __P((void));
    192 #endif
    193 
    194 	/*
    195 	 * Initialize the current process pointer (curproc) before
    196 	 * any possible traps/probes to simplify trap processing.
    197 	 */
    198 	p = &proc0;
    199 	curproc = p;
    200 	/*
    201 	 * Attempt to find console and initialize
    202 	 * in case of early panic or other messages.
    203 	 */
    204 	consinit();
    205 	printf("%s", copyright);
    206 
    207 	uvm_init();
    208 
    209 	/* Do machine-dependent initialization. */
    210 	cpu_startup();
    211 
    212 	/* Initialize callouts. */
    213 	callout_startup();
    214 
    215 	/*
    216 	 * Initialize mbuf's.  Do this now because we might attempt to
    217 	 * allocate mbufs or mbuf clusters during autoconfiguration.
    218 	 */
    219 	mbinit();
    220 
    221 	/* Initialize sockets. */
    222 	soinit();
    223 
    224 	/*
    225 	 * The following 3 things must be done before autoconfiguration.
    226 	 */
    227 	disk_init();		/* initialize disk list */
    228 	tty_init();		/* initialize tty list */
    229 #if NRND > 0
    230 	rnd_init();		/* initialize RNG */
    231 #endif
    232 
    233 	/*
    234 	 * Initialize process and pgrp structures.
    235 	 */
    236 	procinit();
    237 
    238 	/*
    239 	 * Create process 0 (the swapper).
    240 	 */
    241 	s = proclist_lock_write();
    242 	LIST_INSERT_HEAD(&allproc, p, p_list);
    243 	proclist_unlock_write(s);
    244 
    245 	p->p_pgrp = &pgrp0;
    246 	LIST_INSERT_HEAD(PGRPHASH(0), &pgrp0, pg_hash);
    247 	LIST_INIT(&pgrp0.pg_members);
    248 	LIST_INSERT_HEAD(&pgrp0.pg_members, p, p_pglist);
    249 
    250 	pgrp0.pg_session = &session0;
    251 	session0.s_count = 1;
    252 	session0.s_sid = p->p_pid;
    253 	session0.s_leader = p;
    254 
    255 	/*
    256 	 * Set P_NOCLDWAIT so that kernel threads are reparented to
    257 	 * init(8) when they exit.  init(8) can easily wait them out
    258 	 * for us.
    259 	 */
    260 	p->p_flag = P_INMEM | P_SYSTEM | P_NOCLDWAIT;
    261 	p->p_stat = SONPROC;
    262 	p->p_nice = NZERO;
    263 	p->p_emul = &emul_netbsd;
    264 	strncpy(p->p_comm, "swapper", MAXCOMLEN);
    265 
    266 	callout_init(&p->p_realit_ch);
    267 	callout_init(&p->p_tsleep_ch);
    268 
    269 	/* Create credentials. */
    270 	cred0.p_refcnt = 1;
    271 	p->p_cred = &cred0;
    272 	p->p_ucred = crget();
    273 	p->p_ucred->cr_ngroups = 1;	/* group 0 */
    274 
    275 	/* Create the file descriptor table. */
    276 	finit();
    277 	p->p_fd = &filedesc0.fd_fd;
    278 	fdinit1(&filedesc0);
    279 
    280 	/* Create the CWD info. */
    281 	p->p_cwdi = &cwdi0;
    282 	cwdi0.cwdi_cmask = cmask;
    283 	cwdi0.cwdi_refcnt = 1;
    284 
    285 	/* Create the limits structures. */
    286 	p->p_limit = &limit0;
    287 	for (i = 0; i < sizeof(p->p_rlimit)/sizeof(p->p_rlimit[0]); i++)
    288 		limit0.pl_rlimit[i].rlim_cur =
    289 		    limit0.pl_rlimit[i].rlim_max = RLIM_INFINITY;
    290 
    291 	limit0.pl_rlimit[RLIMIT_NOFILE].rlim_max = maxfiles;
    292 	limit0.pl_rlimit[RLIMIT_NOFILE].rlim_cur =
    293 	    maxfiles < NOFILE ? maxfiles : NOFILE;
    294 
    295 	limit0.pl_rlimit[RLIMIT_NPROC].rlim_max = maxproc;
    296 	limit0.pl_rlimit[RLIMIT_NPROC].rlim_cur =
    297 	    maxproc < MAXUPRC ? maxproc : MAXUPRC;
    298 
    299 	i = ptoa(uvmexp.free);
    300 	limit0.pl_rlimit[RLIMIT_RSS].rlim_max = i;
    301 	limit0.pl_rlimit[RLIMIT_MEMLOCK].rlim_max = i;
    302 	limit0.pl_rlimit[RLIMIT_MEMLOCK].rlim_cur = i / 3;
    303 	limit0.pl_corename = defcorename;
    304 	limit0.p_refcnt = 1;
    305 
    306 	/*
    307 	 * Initialize proc0's vmspace, which uses the kernel pmap.
    308 	 * All kernel processes (which never have user space mappings)
    309 	 * share proc0's vmspace, and thus, the kernel pmap.
    310 	 */
    311 	uvmspace_init(&vmspace0, pmap_kernel(), round_page(VM_MIN_ADDRESS),
    312 	    trunc_page(VM_MAX_ADDRESS), TRUE);
    313 	p->p_vmspace = &vmspace0;
    314 
    315 	p->p_addr = proc0paddr;				/* XXX */
    316 
    317 	/*
    318 	 * We continue to place resource usage info in the
    319 	 * user struct so they're pageable.
    320 	 */
    321 	p->p_stats = &p->p_addr->u_stats;
    322 
    323 	/*
    324 	 * Charge root for one process.
    325 	 */
    326 	(void)chgproccnt(0, 1);
    327 
    328 	rqinit();
    329 
    330 	/* Configure virtual memory system, set vm rlimits. */
    331 	uvm_init_limits(p);
    332 
    333 	/* Initialize the file systems. */
    334 #if defined(NFSSERVER) || defined(NFS)
    335 	nfs_init();			/* initialize server/shared data */
    336 #endif
    337 	vfsinit();
    338 
    339 	/* Configure the system hardware.  This will enable interrupts. */
    340 	configure();
    341 
    342 #ifdef SYSVSHM
    343 	/* Initialize System V style shared memory. */
    344 	shminit();
    345 #endif
    346 
    347 #ifdef SYSVSEM
    348 	/* Initialize System V style semaphores. */
    349 	seminit();
    350 #endif
    351 
    352 #ifdef SYSVMSG
    353 	/* Initialize System V style message queues. */
    354 	msginit();
    355 #endif
    356 
    357 	/* Attach pseudo-devices. */
    358 	for (pdev = pdevinit; pdev->pdev_attach != NULL; pdev++)
    359 		(*pdev->pdev_attach)(pdev->pdev_count);
    360 
    361 	/*
    362 	 * Initialize protocols.  Block reception of incoming packets
    363 	 * until everything is ready.
    364 	 */
    365 	s = splimp();
    366 	ifinit();
    367 	domaininit();
    368 	splx(s);
    369 
    370 #ifdef GPROF
    371 	/* Initialize kernel profiling. */
    372 	kmstartup();
    373 #endif
    374 
    375 	/* Initialize system accouting. */
    376 	acct_init();
    377 
    378 	/*
    379 	 * Initialize signal-related data structures, and signal state
    380 	 * for proc0.
    381 	 */
    382 	signal_init();
    383 	p->p_sigacts = &sigacts0;
    384 	siginit(p);
    385 
    386 	/* Kick off timeout driven events by calling first time. */
    387 	roundrobin(NULL);
    388 	schedcpu(NULL);
    389 
    390 	/*
    391 	 * Create process 1 (init(8)).  We do this now, as Unix has
    392 	 * historically had init be process 1, and changing this would
    393 	 * probably upset a lot of people.
    394 	 *
    395 	 * Note that process 1 won't immediately exec init(8), but will
    396 	 * wait for us to inform it that the root file system has been
    397 	 * mounted.
    398 	 */
    399 	if (fork1(p, 0, SIGCHLD, NULL, 0, start_init, NULL, NULL, &initproc))
    400 		panic("fork init");
    401 
    402 	/*
    403 	 * Create any kernel threads who's creation was deferred because
    404 	 * initproc had not yet been created.
    405 	 */
    406 	kthread_run_deferred_queue();
    407 
    408 	/*
    409 	 * Now that device driver threads have been created, wait for
    410 	 * them to finish any deferred autoconfiguration.  Note we don't
    411 	 * need to lock this semaphore, since we haven't booted any
    412 	 * secondary processors, yet.
    413 	 */
    414 	while (config_pending)
    415 		(void) tsleep((void *)&config_pending, PWAIT, "cfpend", 0);
    416 
    417 	/*
    418 	 * Now that autoconfiguration has completed, we can determine
    419 	 * the root and dump devices.
    420 	 */
    421 	cpu_rootconf();
    422 	cpu_dumpconf();
    423 
    424 	/* Mount the root file system. */
    425 	do {
    426 		domountroothook();
    427 		if ((error = vfs_mountroot())) {
    428 			printf("cannot mount root, error = %d\n", error);
    429 			boothowto |= RB_ASKNAME;
    430 			setroot(root_device,
    431 			    (rootdev != NODEV) ? DISKPART(rootdev) : 0);
    432 		}
    433 	} while (error != 0);
    434 	mountroothook_destroy();
    435 
    436 	mountlist.cqh_first->mnt_flag |= MNT_ROOTFS;
    437 	mountlist.cqh_first->mnt_op->vfs_refcount++;
    438 
    439 	/*
    440 	 * Get the vnode for '/'.  Set filedesc0.fd_fd.fd_cdir to
    441 	 * reference it.
    442 	 */
    443 	if (VFS_ROOT(mountlist.cqh_first, &rootvnode))
    444 		panic("cannot find root vnode");
    445 	cwdi0.cwdi_cdir = rootvnode;
    446 	VREF(cwdi0.cwdi_cdir);
    447 	VOP_UNLOCK(rootvnode, 0);
    448 	cwdi0.cwdi_rdir = NULL;
    449 
    450 	/*
    451 	 * Now that root is mounted, we can fixup initproc's CWD
    452 	 * info.  All other processes are kthreads, which merely
    453 	 * share proc0's CWD info.
    454 	 */
    455 	initproc->p_cwdi->cwdi_cdir = rootvnode;
    456 	VREF(initproc->p_cwdi->cwdi_cdir);
    457 	initproc->p_cwdi->cwdi_rdir = NULL;
    458 
    459 	/*
    460 	 * Now can look at time, having had a chance to verify the time
    461 	 * from the file system.  Reset p->p_rtime as it may have been
    462 	 * munched in mi_switch() after the time got set.
    463 	 */
    464 	proclist_lock_read();
    465 	s = splclock();		/* so we can read time */
    466 	for (p = LIST_FIRST(&allproc); p != NULL;
    467 	     p = LIST_NEXT(p, p_list)) {
    468 		p->p_stats->p_start = curcpu()->ci_schedstate.spc_runtime =
    469 		    mono_time = boottime = time;
    470 		p->p_rtime.tv_sec = p->p_rtime.tv_usec = 0;
    471 	}
    472 	splx(s);
    473 	proclist_unlock_read();
    474 
    475 	/* Create the pageout daemon kernel thread. */
    476 	uvm_swap_init();
    477 	if (kthread_create1(start_pagedaemon, NULL, NULL, "pagedaemon"))
    478 		panic("fork pagedaemon");
    479 
    480 	/* Create the process reaper kernel thread. */
    481 	if (kthread_create1(start_reaper, NULL, NULL, "reaper"))
    482 		panic("fork reaper");
    483 
    484 	/* Create the filesystem syncer kernel thread. */
    485 	if (kthread_create1(sched_sync, NULL, NULL, "ioflush"))
    486 		panic("fork syncer");
    487 
    488 #if defined(MULTIPROCESSOR)
    489 	/* Boot the secondary processors. */
    490 	cpu_boot_secondary_processors();
    491 #endif
    492 
    493 	/*
    494 	 * Okay, now we can let init(8) exec!  It's off to userland!
    495 	 */
    496 	start_init_exec = 1;
    497 	wakeup((void *)&start_init_exec);
    498 
    499 	/* The scheduler is an infinite loop. */
    500 	uvm_scheduler();
    501 	/* NOTREACHED */
    502 }
    503 
    504 static void
    505 check_console(p)
    506 	struct proc *p;
    507 {
    508 	struct nameidata nd;
    509 	int error;
    510 
    511 	NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, "/dev/console", p);
    512 	error = namei(&nd);
    513 	if (error == 0)
    514 		vrele(nd.ni_vp);
    515 	else if (error == ENOENT)
    516 		printf("warning: no /dev/console\n");
    517 	else
    518 		printf("warning: lookup /dev/console: error %d\n", error);
    519 }
    520 
    521 /*
    522  * List of paths to try when searching for "init".
    523  */
    524 static char *initpaths[] = {
    525 	"/sbin/init",
    526 	"/sbin/oinit",
    527 	"/sbin/init.bak",
    528 	NULL,
    529 };
    530 
    531 /*
    532  * Start the initial user process; try exec'ing each pathname in "initpaths".
    533  * The program is invoked with one argument containing the boot flags.
    534  */
    535 static void
    536 start_init(arg)
    537 	void *arg;
    538 {
    539 	struct proc *p = arg;
    540 	vaddr_t addr;
    541 	struct sys_execve_args /* {
    542 		syscallarg(const char *) path;
    543 		syscallarg(char * const *) argp;
    544 		syscallarg(char * const *) envp;
    545 	} */ args;
    546 	int options, i, error;
    547 	register_t retval[2];
    548 	char flags[4], *flagsp;
    549 	char **pathp, *path, *slash, *ucp, **uap, *arg0, *arg1 = NULL;
    550 
    551 	/*
    552 	 * Now in process 1.
    553 	 */
    554 	strncpy(p->p_comm, "init", MAXCOMLEN);
    555 
    556 	/*
    557 	 * Wait for main() to tell us that it's safe to exec.
    558 	 */
    559 	while (start_init_exec == 0)
    560 		(void) tsleep((void *)&start_init_exec, PWAIT, "initexec", 0);
    561 
    562 	/*
    563 	 * This is not the right way to do this.  We really should
    564 	 * hand-craft a descriptor onto /dev/console to hand to init,
    565 	 * but that's a _lot_ more work, and the benefit from this easy
    566 	 * hack makes up for the "good is the enemy of the best" effect.
    567 	 */
    568 	check_console(p);
    569 
    570 	/*
    571 	 * Need just enough stack to hold the faked-up "execve()" arguments.
    572 	 */
    573 	addr = USRSTACK - PAGE_SIZE;
    574 	if (uvm_map(&p->p_vmspace->vm_map, &addr, PAGE_SIZE,
    575                     NULL, UVM_UNKNOWN_OFFSET,
    576                     UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_COPY,
    577 		    UVM_ADV_NORMAL,
    578                     UVM_FLAG_FIXED|UVM_FLAG_OVERLAY|UVM_FLAG_COPYONW))
    579 		!= KERN_SUCCESS)
    580 		panic("init: couldn't allocate argument space");
    581 	p->p_vmspace->vm_maxsaddr = (caddr_t)addr;
    582 
    583 	for (pathp = &initpaths[0]; (path = *pathp) != NULL; pathp++) {
    584 		ucp = (char *)(addr + PAGE_SIZE);
    585 
    586 		/*
    587 		 * Construct the boot flag argument.
    588 		 */
    589 		flagsp = flags;
    590 		*flagsp++ = '-';
    591 		options = 0;
    592 
    593 		if (boothowto & RB_SINGLE) {
    594 			*flagsp++ = 's';
    595 			options = 1;
    596 		}
    597 #ifdef notyet
    598 		if (boothowto & RB_FASTBOOT) {
    599 			*flagsp++ = 'f';
    600 			options = 1;
    601 		}
    602 #endif
    603 
    604 		/*
    605 		 * Move out the flags (arg 1), if necessary.
    606 		 */
    607 		if (options != 0) {
    608 			*flagsp++ = '\0';
    609 			i = flagsp - flags;
    610 #ifdef DEBUG
    611 			printf("init: copying out flags `%s' %d\n", flags, i);
    612 #endif
    613 			(void)copyout((caddr_t)flags, (caddr_t)(ucp -= i), i);
    614 			arg1 = ucp;
    615 		}
    616 
    617 		/*
    618 		 * Move out the file name (also arg 0).
    619 		 */
    620 		i = strlen(path) + 1;
    621 #ifdef DEBUG
    622 		printf("init: copying out path `%s' %d\n", path, i);
    623 #endif
    624 		(void)copyout((caddr_t)path, (caddr_t)(ucp -= i), i);
    625 		arg0 = ucp;
    626 
    627 		/*
    628 		 * Move out the arg pointers.
    629 		 */
    630 		uap = (char **)((long)ucp & ~ALIGNBYTES);
    631 		(void)suword((caddr_t)--uap, 0);	/* terminator */
    632 		if (options != 0)
    633 			(void)suword((caddr_t)--uap, (long)arg1);
    634 		slash = strrchr(path, '/');
    635 		if (slash)
    636 			(void)suword((caddr_t)--uap,
    637 			    (long)arg0 + (slash + 1 - path));
    638 		else
    639 			(void)suword((caddr_t)--uap, (long)arg0);
    640 
    641 		/*
    642 		 * Point at the arguments.
    643 		 */
    644 		SCARG(&args, path) = arg0;
    645 		SCARG(&args, argp) = uap;
    646 		SCARG(&args, envp) = NULL;
    647 
    648 		/*
    649 		 * Now try to exec the program.  If can't for any reason
    650 		 * other than it doesn't exist, complain.
    651 		 */
    652 		error = sys_execve(p, &args, retval);
    653 		if (error == 0 || error == EJUSTRETURN)
    654 			return;
    655 		if (error != ENOENT)
    656 			printf("exec %s: error %d\n", path, error);
    657 	}
    658 	printf("init: not found\n");
    659 	panic("no init");
    660 }
    661 
    662 /* ARGSUSED */
    663 static void
    664 start_pagedaemon(arg)
    665 	void *arg;
    666 {
    667 
    668 	uvm_pageout();
    669 	/* NOTREACHED */
    670 }
    671 
    672 /* ARGSUSED */
    673 static void
    674 start_reaper(arg)
    675 	void *arg;
    676 {
    677 
    678 	reaper();
    679 	/* NOTREACHED */
    680 }
    681