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init_main.c revision 1.165
      1 /*	$NetBSD: init_main.c,v 1.165 2000/03/23 06:30:07 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 struct	timeval runtime;
    142 
    143 __volatile int start_init_exec;		/* semaphore for start_init() */
    144 
    145 static void check_console __P((struct proc *p));
    146 static void start_init __P((void *));
    147 static void start_pagedaemon __P((void *));
    148 static void start_reaper __P((void *));
    149 void main __P((void));
    150 
    151 extern char sigcode[], esigcode[];
    152 #ifdef SYSCALL_DEBUG
    153 extern char *syscallnames[];
    154 #endif
    155 
    156 struct emul emul_netbsd = {
    157 	"netbsd",
    158 	NULL,
    159 	sendsig,
    160 	SYS_syscall,
    161 	SYS_MAXSYSCALL,
    162 	sysent,
    163 #ifdef SYSCALL_DEBUG
    164 	syscallnames,
    165 #else
    166 	NULL,
    167 #endif
    168 	0,
    169 	copyargs,
    170 	setregs,
    171 	sigcode,
    172 	esigcode,
    173 };
    174 
    175 /*
    176  * System startup; initialize the world, create process 0, mount root
    177  * filesystem, and fork to create init and pagedaemon.  Most of the
    178  * hard work is done in the lower-level initialization routines including
    179  * startup(), which does memory initialization and autoconfiguration.
    180  */
    181 void
    182 main()
    183 {
    184 	struct proc *p;
    185 	struct pdevinit *pdev;
    186 	int i, s, error;
    187 	extern struct pdevinit pdevinit[];
    188 	extern void roundrobin __P((void *));
    189 	extern void schedcpu __P((void *));
    190 	extern void disk_init __P((void));
    191 #if defined(NFSSERVER) || defined(NFS)
    192 	extern void nfs_init __P((void));
    193 #endif
    194 
    195 	/*
    196 	 * Initialize the current process pointer (curproc) before
    197 	 * any possible traps/probes to simplify trap processing.
    198 	 */
    199 	p = &proc0;
    200 	curproc = p;
    201 	/*
    202 	 * Attempt to find console and initialize
    203 	 * in case of early panic or other messages.
    204 	 */
    205 	consinit();
    206 	printf("%s", copyright);
    207 
    208 	uvm_init();
    209 
    210 	/* Initialize callouts. */
    211 	callout_startup();
    212 
    213 	/* Do machine-dependent initialization. */
    214 	cpu_startup();
    215 
    216 	/* Finish initializing callouts. */
    217 	callout_startup1();
    218 
    219 	/*
    220 	 * Initialize mbuf's.  Do this now because we might attempt to
    221 	 * allocate mbufs or mbuf clusters during autoconfiguration.
    222 	 */
    223 	mbinit();
    224 
    225 	/* Initialize sockets. */
    226 	soinit();
    227 
    228 	/*
    229 	 * The following 3 things must be done before autoconfiguration.
    230 	 */
    231 	disk_init();		/* initialize disk list */
    232 	tty_init();		/* initialize tty list */
    233 #if NRND > 0
    234 	rnd_init();		/* initialize RNG */
    235 #endif
    236 
    237 	/*
    238 	 * Initialize process and pgrp structures.
    239 	 */
    240 	procinit();
    241 
    242 	/*
    243 	 * Create process 0 (the swapper).
    244 	 */
    245 	s = proclist_lock_write();
    246 	LIST_INSERT_HEAD(&allproc, p, p_list);
    247 	proclist_unlock_write(s);
    248 
    249 	p->p_pgrp = &pgrp0;
    250 	LIST_INSERT_HEAD(PGRPHASH(0), &pgrp0, pg_hash);
    251 	LIST_INIT(&pgrp0.pg_members);
    252 	LIST_INSERT_HEAD(&pgrp0.pg_members, p, p_pglist);
    253 
    254 	pgrp0.pg_session = &session0;
    255 	session0.s_count = 1;
    256 	session0.s_sid = p->p_pid;
    257 	session0.s_leader = p;
    258 
    259 	/*
    260 	 * Set P_NOCLDWAIT so that kernel threads are reparented to
    261 	 * init(8) when they exit.  init(8) can easily wait them out
    262 	 * for us.
    263 	 */
    264 	p->p_flag = P_INMEM | P_SYSTEM | P_NOCLDWAIT;
    265 	p->p_stat = SRUN;
    266 	p->p_nice = NZERO;
    267 	p->p_emul = &emul_netbsd;
    268 	strncpy(p->p_comm, "swapper", MAXCOMLEN);
    269 
    270 	callout_init(&p->p_realit_ch);
    271 	callout_init(&p->p_tsleep_ch);
    272 
    273 	/* Create credentials. */
    274 	cred0.p_refcnt = 1;
    275 	p->p_cred = &cred0;
    276 	p->p_ucred = crget();
    277 	p->p_ucred->cr_ngroups = 1;	/* group 0 */
    278 
    279 	/* Create the file descriptor table. */
    280 	finit();
    281 	p->p_fd = &filedesc0.fd_fd;
    282 	fdinit1(&filedesc0);
    283 
    284 	/* Create the CWD info. */
    285 	p->p_cwdi = &cwdi0;
    286 	cwdi0.cwdi_cmask = cmask;
    287 	cwdi0.cwdi_refcnt = 1;
    288 
    289 	/* Create the limits structures. */
    290 	p->p_limit = &limit0;
    291 	for (i = 0; i < sizeof(p->p_rlimit)/sizeof(p->p_rlimit[0]); i++)
    292 		limit0.pl_rlimit[i].rlim_cur =
    293 		    limit0.pl_rlimit[i].rlim_max = RLIM_INFINITY;
    294 
    295 	limit0.pl_rlimit[RLIMIT_NOFILE].rlim_max = maxfiles;
    296 	limit0.pl_rlimit[RLIMIT_NOFILE].rlim_cur =
    297 	    maxfiles < NOFILE ? maxfiles : NOFILE;
    298 
    299 	limit0.pl_rlimit[RLIMIT_NPROC].rlim_max = maxproc;
    300 	limit0.pl_rlimit[RLIMIT_NPROC].rlim_cur =
    301 	    maxproc < MAXUPRC ? maxproc : MAXUPRC;
    302 
    303 	i = ptoa(uvmexp.free);
    304 	limit0.pl_rlimit[RLIMIT_RSS].rlim_max = i;
    305 	limit0.pl_rlimit[RLIMIT_MEMLOCK].rlim_max = i;
    306 	limit0.pl_rlimit[RLIMIT_MEMLOCK].rlim_cur = i / 3;
    307 	limit0.pl_corename = defcorename;
    308 	limit0.p_refcnt = 1;
    309 
    310 	/*
    311 	 * Initialize proc0's vmspace, which uses the kernel pmap.
    312 	 * All kernel processes (which never have user space mappings)
    313 	 * share proc0's vmspace, and thus, the kernel pmap.
    314 	 */
    315 	uvmspace_init(&vmspace0, pmap_kernel(), round_page(VM_MIN_ADDRESS),
    316 	    trunc_page(VM_MAX_ADDRESS), TRUE);
    317 	p->p_vmspace = &vmspace0;
    318 
    319 	p->p_addr = proc0paddr;				/* XXX */
    320 
    321 	/*
    322 	 * We continue to place resource usage info in the
    323 	 * user struct so they're pageable.
    324 	 */
    325 	p->p_stats = &p->p_addr->u_stats;
    326 
    327 	/*
    328 	 * Charge root for one process.
    329 	 */
    330 	(void)chgproccnt(0, 1);
    331 
    332 	rqinit();
    333 
    334 	/* Configure virtual memory system, set vm rlimits. */
    335 	uvm_init_limits(p);
    336 
    337 	/* Initialize the file systems. */
    338 #if defined(NFSSERVER) || defined(NFS)
    339 	nfs_init();			/* initialize server/shared data */
    340 #endif
    341 	vfsinit();
    342 
    343 	/* Configure the system hardware.  This will enable interrupts. */
    344 	configure();
    345 
    346 #ifdef SYSVSHM
    347 	/* Initialize System V style shared memory. */
    348 	shminit();
    349 #endif
    350 
    351 #ifdef SYSVSEM
    352 	/* Initialize System V style semaphores. */
    353 	seminit();
    354 #endif
    355 
    356 #ifdef SYSVMSG
    357 	/* Initialize System V style message queues. */
    358 	msginit();
    359 #endif
    360 
    361 	/* Attach pseudo-devices. */
    362 	for (pdev = pdevinit; pdev->pdev_attach != NULL; pdev++)
    363 		(*pdev->pdev_attach)(pdev->pdev_count);
    364 
    365 	/*
    366 	 * Initialize protocols.  Block reception of incoming packets
    367 	 * until everything is ready.
    368 	 */
    369 	s = splimp();
    370 	ifinit();
    371 	domaininit();
    372 	splx(s);
    373 
    374 #ifdef GPROF
    375 	/* Initialize kernel profiling. */
    376 	kmstartup();
    377 #endif
    378 
    379 	/* Initialize system accouting. */
    380 	acct_init();
    381 
    382 	/*
    383 	 * Initialize signal-related data structures, and signal state
    384 	 * for proc0.
    385 	 */
    386 	signal_init();
    387 	p->p_sigacts = &sigacts0;
    388 	siginit(p);
    389 
    390 	/* Kick off timeout driven events by calling first time. */
    391 	roundrobin(NULL);
    392 	schedcpu(NULL);
    393 
    394 	/*
    395 	 * Create process 1 (init(8)).  We do this now, as Unix has
    396 	 * historically had init be process 1, and changing this would
    397 	 * probably upset a lot of people.
    398 	 *
    399 	 * Note that process 1 won't immediately exec init(8), but will
    400 	 * wait for us to inform it that the root file system has been
    401 	 * mounted.
    402 	 */
    403 	if (fork1(p, 0, SIGCHLD, NULL, 0, NULL, &initproc))
    404 		panic("fork init");
    405 	cpu_set_kpc(initproc, start_init, initproc);
    406 
    407 	/*
    408 	 * Create any kernel threads who's creation was deferred because
    409 	 * initproc had not yet been created.
    410 	 */
    411 	kthread_run_deferred_queue();
    412 
    413 	/*
    414 	 * Now that device driver threads have been created, wait for
    415 	 * them to finish any deferred autoconfiguration.  Note we don't
    416 	 * need to lock this semaphore, since we haven't booted any
    417 	 * secondary processors, yet.
    418 	 */
    419 	while (config_pending)
    420 		(void) tsleep((void *)&config_pending, PWAIT, "cfpend", 0);
    421 
    422 	/*
    423 	 * Now that autoconfiguration has completed, we can determine
    424 	 * the root and dump devices.
    425 	 */
    426 	cpu_rootconf();
    427 	cpu_dumpconf();
    428 
    429 	/* Mount the root file system. */
    430 	do {
    431 		domountroothook();
    432 		if ((error = vfs_mountroot())) {
    433 			printf("cannot mount root, error = %d\n", error);
    434 			boothowto |= RB_ASKNAME;
    435 			setroot(root_device,
    436 			    (rootdev != NODEV) ? DISKPART(rootdev) : 0);
    437 		}
    438 	} while (error != 0);
    439 	mountroothook_destroy();
    440 
    441 	mountlist.cqh_first->mnt_flag |= MNT_ROOTFS;
    442 	mountlist.cqh_first->mnt_op->vfs_refcount++;
    443 
    444 	/*
    445 	 * Get the vnode for '/'.  Set filedesc0.fd_fd.fd_cdir to
    446 	 * reference it.
    447 	 */
    448 	if (VFS_ROOT(mountlist.cqh_first, &rootvnode))
    449 		panic("cannot find root vnode");
    450 	cwdi0.cwdi_cdir = rootvnode;
    451 	VREF(cwdi0.cwdi_cdir);
    452 	VOP_UNLOCK(rootvnode, 0);
    453 	cwdi0.cwdi_rdir = NULL;
    454 
    455 	/*
    456 	 * Now that root is mounted, we can fixup initproc's CWD
    457 	 * info.  All other processes are kthreads, which merely
    458 	 * share proc0's CWD info.
    459 	 */
    460 	initproc->p_cwdi->cwdi_cdir = rootvnode;
    461 	VREF(initproc->p_cwdi->cwdi_cdir);
    462 	initproc->p_cwdi->cwdi_rdir = NULL;
    463 
    464 	/*
    465 	 * Now can look at time, having had a chance to verify the time
    466 	 * from the file system.  Reset p->p_rtime as it may have been
    467 	 * munched in mi_switch() after the time got set.
    468 	 */
    469 	proclist_lock_read();
    470 	s = splclock();		/* so we can read time */
    471 	for (p = LIST_FIRST(&allproc); p != NULL;
    472 	     p = LIST_NEXT(p, p_list)) {
    473 		p->p_stats->p_start = runtime = mono_time = boottime = time;
    474 		p->p_rtime.tv_sec = p->p_rtime.tv_usec = 0;
    475 	}
    476 	splx(s);
    477 	proclist_unlock_read();
    478 
    479 	/* Create the pageout daemon kernel thread. */
    480 	uvm_swap_init();
    481 	if (kthread_create1(start_pagedaemon, NULL, NULL, "pagedaemon"))
    482 		panic("fork pagedaemon");
    483 
    484 	/* Create the process reaper kernel thread. */
    485 	if (kthread_create1(start_reaper, NULL, NULL, "reaper"))
    486 		panic("fork reaper");
    487 
    488 	/* Create the filesystem syncer kernel thread. */
    489 	if (kthread_create1(sched_sync, NULL, NULL, "ioflush"))
    490 		panic("fork syncer");
    491 
    492 #if defined(MULTIPROCESSOR)
    493 	/* Boot the secondary processors. */
    494 	cpu_boot_secondary_processors();
    495 #endif
    496 
    497 	/*
    498 	 * Okay, now we can let init(8) exec!  It's off to userland!
    499 	 */
    500 	start_init_exec = 1;
    501 	wakeup((void *)&start_init_exec);
    502 
    503 	/* The scheduler is an infinite loop. */
    504 	uvm_scheduler();
    505 	/* NOTREACHED */
    506 }
    507 
    508 static void
    509 check_console(p)
    510 	struct proc *p;
    511 {
    512 	struct nameidata nd;
    513 	int error;
    514 
    515 	NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, "/dev/console", p);
    516 	error = namei(&nd);
    517 	if (error == 0)
    518 		vrele(nd.ni_vp);
    519 	else if (error == ENOENT)
    520 		printf("warning: no /dev/console\n");
    521 	else
    522 		printf("warning: lookup /dev/console: error %d\n", error);
    523 }
    524 
    525 /*
    526  * List of paths to try when searching for "init".
    527  */
    528 static char *initpaths[] = {
    529 	"/sbin/init",
    530 	"/sbin/oinit",
    531 	"/sbin/init.bak",
    532 	NULL,
    533 };
    534 
    535 /*
    536  * Start the initial user process; try exec'ing each pathname in "initpaths".
    537  * The program is invoked with one argument containing the boot flags.
    538  */
    539 static void
    540 start_init(arg)
    541 	void *arg;
    542 {
    543 	struct proc *p = arg;
    544 	vaddr_t addr;
    545 	struct sys_execve_args /* {
    546 		syscallarg(const char *) path;
    547 		syscallarg(char * const *) argp;
    548 		syscallarg(char * const *) envp;
    549 	} */ args;
    550 	int options, i, error;
    551 	register_t retval[2];
    552 	char flags[4], *flagsp;
    553 	char **pathp, *path, *slash, *ucp, **uap, *arg0, *arg1 = NULL;
    554 
    555 	/*
    556 	 * Now in process 1.
    557 	 */
    558 	strncpy(p->p_comm, "init", MAXCOMLEN);
    559 
    560 	/*
    561 	 * Wait for main() to tell us that it's safe to exec.
    562 	 */
    563 	while (start_init_exec == 0)
    564 		(void) tsleep((void *)&start_init_exec, PWAIT, "initexec", 0);
    565 
    566 	/*
    567 	 * This is not the right way to do this.  We really should
    568 	 * hand-craft a descriptor onto /dev/console to hand to init,
    569 	 * but that's a _lot_ more work, and the benefit from this easy
    570 	 * hack makes up for the "good is the enemy of the best" effect.
    571 	 */
    572 	check_console(p);
    573 
    574 	/*
    575 	 * Need just enough stack to hold the faked-up "execve()" arguments.
    576 	 */
    577 	addr = USRSTACK - PAGE_SIZE;
    578 	if (uvm_map(&p->p_vmspace->vm_map, &addr, PAGE_SIZE,
    579                     NULL, UVM_UNKNOWN_OFFSET,
    580                     UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_COPY,
    581 		    UVM_ADV_NORMAL,
    582                     UVM_FLAG_FIXED|UVM_FLAG_OVERLAY|UVM_FLAG_COPYONW))
    583 		!= KERN_SUCCESS)
    584 		panic("init: couldn't allocate argument space");
    585 	p->p_vmspace->vm_maxsaddr = (caddr_t)addr;
    586 
    587 	for (pathp = &initpaths[0]; (path = *pathp) != NULL; pathp++) {
    588 		ucp = (char *)(addr + PAGE_SIZE);
    589 
    590 		/*
    591 		 * Construct the boot flag argument.
    592 		 */
    593 		flagsp = flags;
    594 		*flagsp++ = '-';
    595 		options = 0;
    596 
    597 		if (boothowto & RB_SINGLE) {
    598 			*flagsp++ = 's';
    599 			options = 1;
    600 		}
    601 #ifdef notyet
    602 		if (boothowto & RB_FASTBOOT) {
    603 			*flagsp++ = 'f';
    604 			options = 1;
    605 		}
    606 #endif
    607 
    608 		/*
    609 		 * Move out the flags (arg 1), if necessary.
    610 		 */
    611 		if (options != 0) {
    612 			*flagsp++ = '\0';
    613 			i = flagsp - flags;
    614 #ifdef DEBUG
    615 			printf("init: copying out flags `%s' %d\n", flags, i);
    616 #endif
    617 			(void)copyout((caddr_t)flags, (caddr_t)(ucp -= i), i);
    618 			arg1 = ucp;
    619 		}
    620 
    621 		/*
    622 		 * Move out the file name (also arg 0).
    623 		 */
    624 		i = strlen(path) + 1;
    625 #ifdef DEBUG
    626 		printf("init: copying out path `%s' %d\n", path, i);
    627 #endif
    628 		(void)copyout((caddr_t)path, (caddr_t)(ucp -= i), i);
    629 		arg0 = ucp;
    630 
    631 		/*
    632 		 * Move out the arg pointers.
    633 		 */
    634 		uap = (char **)((long)ucp & ~ALIGNBYTES);
    635 		(void)suword((caddr_t)--uap, 0);	/* terminator */
    636 		if (options != 0)
    637 			(void)suword((caddr_t)--uap, (long)arg1);
    638 		slash = strrchr(path, '/');
    639 		if (slash)
    640 			(void)suword((caddr_t)--uap,
    641 			    (long)arg0 + (slash + 1 - path));
    642 		else
    643 			(void)suword((caddr_t)--uap, (long)arg0);
    644 
    645 		/*
    646 		 * Point at the arguments.
    647 		 */
    648 		SCARG(&args, path) = arg0;
    649 		SCARG(&args, argp) = uap;
    650 		SCARG(&args, envp) = NULL;
    651 
    652 		/*
    653 		 * Now try to exec the program.  If can't for any reason
    654 		 * other than it doesn't exist, complain.
    655 		 */
    656 		error = sys_execve(p, &args, retval);
    657 		if (error == 0 || error == EJUSTRETURN)
    658 			return;
    659 		if (error != ENOENT)
    660 			printf("exec %s: error %d\n", path, error);
    661 	}
    662 	printf("init: not found\n");
    663 	panic("no init");
    664 }
    665 
    666 /* ARGSUSED */
    667 static void
    668 start_pagedaemon(arg)
    669 	void *arg;
    670 {
    671 
    672 	uvm_pageout();
    673 	/* NOTREACHED */
    674 }
    675 
    676 /* ARGSUSED */
    677 static void
    678 start_reaper(arg)
    679 	void *arg;
    680 {
    681 
    682 	reaper();
    683 	/* NOTREACHED */
    684 }
    685