xref: /netbsd-src/sys/kern/init_main.c (revision 53b02e147d4ed531c0d2a5ca9b3e8026ba3e99b5)
1 /*	$NetBSD: init_main.c,v 1.535 2021/04/01 04:41:38 simonb Exp $	*/
2 
3 /*-
4  * Copyright (c) 2008, 2009, 2019 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
17  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
20  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26  * POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 /*
30  * Copyright (c) 1982, 1986, 1989, 1991, 1992, 1993
31  *	The Regents of the University of California.  All rights reserved.
32  * (c) UNIX System Laboratories, Inc.
33  * All or some portions of this file are derived from material licensed
34  * to the University of California by American Telephone and Telegraph
35  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
36  * the permission of UNIX System Laboratories, Inc.
37  *
38  * Redistribution and use in source and binary forms, with or without
39  * modification, are permitted provided that the following conditions
40  * are met:
41  * 1. Redistributions of source code must retain the above copyright
42  *    notice, this list of conditions and the following disclaimer.
43  * 2. Redistributions in binary form must reproduce the above copyright
44  *    notice, this list of conditions and the following disclaimer in the
45  *    documentation and/or other materials provided with the distribution.
46  * 3. Neither the name of the University nor the names of its contributors
47  *    may be used to endorse or promote products derived from this software
48  *    without specific prior written permission.
49  *
50  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
51  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
52  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
53  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
54  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
55  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
56  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
57  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
58  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
59  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
60  * SUCH DAMAGE.
61  *
62  *	@(#)init_main.c	8.16 (Berkeley) 5/14/95
63  */
64 
65 /*
66  * Copyright (c) 1995 Christopher G. Demetriou.  All rights reserved.
67  *
68  * Redistribution and use in source and binary forms, with or without
69  * modification, are permitted provided that the following conditions
70  * are met:
71  * 1. Redistributions of source code must retain the above copyright
72  *    notice, this list of conditions and the following disclaimer.
73  * 2. Redistributions in binary form must reproduce the above copyright
74  *    notice, this list of conditions and the following disclaimer in the
75  *    documentation and/or other materials provided with the distribution.
76  * 3. All advertising materials mentioning features or use of this software
77  *    must display the following acknowledgement:
78  *	This product includes software developed by the University of
79  *	California, Berkeley and its contributors.
80  * 4. Neither the name of the University nor the names of its contributors
81  *    may be used to endorse or promote products derived from this software
82  *    without specific prior written permission.
83  *
84  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
85  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
86  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
87  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
88  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
89  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
90  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
91  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
92  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
93  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
94  * SUCH DAMAGE.
95  *
96  *	@(#)init_main.c	8.16 (Berkeley) 5/14/95
97  */
98 
99 #include <sys/cdefs.h>
100 __KERNEL_RCSID(0, "$NetBSD: init_main.c,v 1.535 2021/04/01 04:41:38 simonb Exp $");
101 
102 #include "opt_cnmagic.h"
103 #include "opt_ddb.h"
104 #include "opt_inet.h"
105 #include "opt_ipsec.h"
106 #include "opt_modular.h"
107 #include "opt_ntp.h"
108 #include "opt_pipe.h"
109 #include "opt_syscall_debug.h"
110 #include "opt_sysv.h"
111 #include "opt_fileassoc.h"
112 #include "opt_ktrace.h"
113 #include "opt_pax.h"
114 #include "opt_compat_netbsd.h"
115 #include "opt_wapbl.h"
116 #include "opt_ptrace.h"
117 #include "opt_splash.h"
118 #include "opt_kernhist.h"
119 #include "opt_gprof.h"
120 
121 #if defined(SPLASHSCREEN) && defined(makeoptions_SPLASHSCREEN_IMAGE)
122 extern void *_binary_splash_image_start;
123 extern void *_binary_splash_image_end;
124 #endif
125 
126 #include "ksyms.h"
127 
128 #include "veriexec.h"
129 
130 #include <sys/param.h>
131 #include <sys/acct.h>
132 #include <sys/filedesc.h>
133 #include <sys/file.h>
134 #include <sys/errno.h>
135 #include <sys/callout.h>
136 #include <sys/cpu.h>
137 #include <sys/cpufreq.h>
138 #include <sys/spldebug.h>
139 #include <sys/kernel.h>
140 #include <sys/mount.h>
141 #include <sys/proc.h>
142 #include <sys/kthread.h>
143 #include <sys/resourcevar.h>
144 #include <sys/signalvar.h>
145 #include <sys/systm.h>
146 #include <sys/vnode.h>
147 #include <sys/fstrans.h>
148 #include <sys/tty.h>
149 #include <sys/conf.h>
150 #include <sys/disklabel.h>
151 #include <sys/buf.h>
152 #include <sys/device.h>
153 #include <sys/exec.h>
154 #include <sys/socketvar.h>
155 #include <sys/protosw.h>
156 #include <sys/percpu.h>
157 #include <sys/pserialize.h>
158 #include <sys/pset.h>
159 #include <sys/sysctl.h>
160 #include <sys/reboot.h>
161 #include <sys/event.h>
162 #include <sys/mbuf.h>
163 #include <sys/sched.h>
164 #include <sys/sleepq.h>
165 #include <sys/ipi.h>
166 #include <sys/iostat.h>
167 #include <sys/vmem.h>
168 #include <sys/uuid.h>
169 #include <sys/extent.h>
170 #include <sys/disk.h>
171 #include <sys/msgbuf.h>
172 #include <sys/module.h>
173 #include <sys/module_hook.h>
174 #include <sys/event.h>
175 #include <sys/lockf.h>
176 #include <sys/once.h>
177 #include <sys/kcpuset.h>
178 #include <sys/ksyms.h>
179 #include <sys/uidinfo.h>
180 #include <sys/kprintf.h>
181 #include <sys/bufq.h>
182 #include <sys/threadpool.h>
183 #include <sys/futex.h>
184 #ifdef IPSEC
185 #include <netipsec/ipsec.h>
186 #endif
187 #include <sys/domain.h>
188 #include <sys/namei.h>
189 #include <sys/rnd.h>
190 #include <sys/pipe.h>
191 #if NVERIEXEC > 0
192 #include <sys/verified_exec.h>
193 #endif /* NVERIEXEC > 0 */
194 #ifdef KTRACE
195 #include <sys/ktrace.h>
196 #endif
197 #include <sys/kauth.h>
198 #include <net80211/ieee80211_netbsd.h>
199 #include <sys/cprng.h>
200 #include <sys/psref.h>
201 #include <sys/radixtree.h>
202 
203 #include <sys/syscall.h>
204 #include <sys/syscallargs.h>
205 
206 #include <sys/pax.h>
207 
208 #include <dev/clock_subr.h>
209 
210 #include <secmodel/secmodel.h>
211 
212 #include <ufs/ufs/quota.h>
213 
214 #include <miscfs/genfs/genfs.h>
215 #include <miscfs/specfs/specdev.h>
216 
217 #include <sys/cpu.h>
218 
219 #include <uvm/uvm.h>	/* extern struct uvm uvm */
220 
221 #include <dev/cons.h>
222 #include <dev/splash/splash.h>
223 
224 #include <net/bpf.h>
225 #include <net/if.h>
226 #include <net/pfil.h>
227 #include <net/raw_cb.h>
228 #include <net/if_llatbl.h>
229 
230 #include <prop/proplib.h>
231 
232 #include <sys/userconf.h>
233 
234 extern struct lwp lwp0;
235 extern time_t rootfstime;
236 
237 #ifndef curlwp
238 struct	lwp *curlwp = &lwp0;
239 #endif
240 struct	proc *initproc;
241 
242 struct	vnode *rootvp, *swapdev_vp;
243 int	boothowto;
244 int	cold __read_mostly = 1;		/* still working on startup */
245 int	shutting_down __read_mostly;	/* system is shutting down */
246 
247 int	start_init_exec;		/* semaphore for start_init() */
248 
249 static void check_console(struct lwp *l);
250 static void start_init(void *);
251 static void configure(void);
252 static void configure2(void);
253 static void configure3(void);
254 void main(void);
255 
256 /*
257  * System startup; initialize the world, create process 0, mount root
258  * filesystem, and fork to create init and pagedaemon.  Most of the
259  * hard work is done in the lower-level initialization routines including
260  * startup(), which does memory initialization and autoconfiguration.
261  */
262 void
263 main(void)
264 {
265 	struct timespec time;
266 	struct lwp *l;
267 	struct proc *p;
268 	int s, error;
269 #ifdef NVNODE_IMPLICIT
270 	int usevnodes;
271 #endif
272 	CPU_INFO_ITERATOR cii;
273 	struct cpu_info *ci;
274 
275 #ifdef DIAGNOSTIC
276 	/*
277 	 * Verify that CPU_INFO_FOREACH() knows about the boot CPU
278 	 * and only the boot CPU at this point.
279 	 */
280 	int cpucount = 0;
281 	for (CPU_INFO_FOREACH(cii, ci)) {
282 		KASSERT(ci == curcpu());
283 		cpucount++;
284 	}
285 	KASSERT(cpucount == 1);
286 #endif
287 
288 	l = &lwp0;
289 #ifndef LWP0_CPU_INFO
290 	l->l_cpu = curcpu();
291 #endif
292 	l->l_pflag |= LP_RUNNING;
293 
294 	/*
295 	 * Attempt to find console and initialize
296 	 * in case of early panic or other messages.
297 	 */
298 	consinit();
299 #ifdef CNMAGIC
300 	cn_set_magic(CNMAGIC);
301 #endif
302 
303 	kernel_lock_init();
304 	once_init();
305 	todr_init();
306 
307 	mi_cpu_init();
308 	kernconfig_lock_init();
309 	kthread_sysinit();
310 
311 	/* Initialize the device switch tables. */
312 	devsw_init();
313 
314 	/* Initialize event counters. */
315 	evcnt_init();
316 
317 	uvm_init();
318 	ubchist_init();
319 	kcpuset_sysinit();
320 
321 	prop_kern_init();
322 
323 #if ((NKSYMS > 0) || (NDDB > 0) || (NMODULAR > 0))
324 	ksyms_init();
325 #endif
326 	kprintf_init();
327 
328 	percpu_init();
329 
330 	/* Initialize lock caches. */
331 	mutex_obj_init();
332 
333 	/* Initialize radix trees (used by numerous subsystems). */
334 	radix_tree_init();
335 
336 	/* Passive serialization. */
337 	pserialize_init();
338 
339 	/* Initialize the extent manager. */
340 	extent_init();
341 
342 	/* Do machine-dependent initialization. */
343 	cpu_startup();
344 
345 	/* Initialize the sysctl subsystem. */
346 	sysctl_init();
347 
348 	/* Initialize callouts, part 1. */
349 	callout_startup();
350 
351 	/* Initialize the kernel authorization subsystem. */
352 	kauth_init();
353 
354 	secmodel_init();
355 
356 	spec_init();
357 
358 	/*
359 	 * Set BPF op vector.  Can't do this in bpf attach, since
360 	 * network drivers attach before bpf.
361 	 */
362 	bpf_setops();
363 
364 	/* Initialize what we can in ipi(9) before CPUs are detected. */
365 	ipi_sysinit();
366 
367 	/* Start module system. */
368 	module_init();
369 	module_hook_init();
370 
371 	/*
372 	 * Initialize the kernel authorization subsystem and start the
373 	 * default security model, if any. We need to do this early
374 	 * enough so that subsystems relying on any of the aforementioned
375 	 * can work properly. Since the security model may dictate the
376 	 * credential inheritance policy, it is needed at least before
377 	 * any process is created, specifically proc0.
378 	 */
379 	module_init_class(MODULE_CLASS_SECMODEL);
380 
381 	/* Initialize the buffer cache */
382 	bufinit();
383 	biohist_init();
384 
385 #ifdef KERNHIST
386 	sysctl_kernhist_init();
387 #endif
388 
389 
390 #if defined(SPLASHSCREEN) && defined(SPLASHSCREEN_IMAGE)
391 	size_t splash_size = (&_binary_splash_image_end -
392 	    &_binary_splash_image_start) * sizeof(void *);
393 	splash_setimage(&_binary_splash_image_start, splash_size);
394 #endif
395 
396 	/* Initialize sockets. */
397 	soinit();
398 
399 	/*
400 	 * The following things must be done before autoconfiguration.
401 	 */
402 	rnd_init();		/* initialize entropy pool */
403 
404 	cprng_init();		/* initialize cryptographic PRNG */
405 
406 	/* Initialize process and pgrp structures. */
407 	procinit();
408 	lwpinit();
409 
410 	/* Must be called after lwpinit (lwpinit_specificdata) */
411 	psref_init();
412 
413 	/* Initialize signal-related data structures. */
414 	signal_init();
415 
416 	/* Initialize resource management. */
417 	resource_init();
418 
419 	/* Create process 0. */
420 	proc0_init();
421 	lwp0_init();
422 
423 	/* Disable preemption during boot. */
424 	kpreempt_disable();
425 
426 	/* Initialize the threadpool system. */
427 	threadpools_init();
428 
429 	/* Initialize the UID hash table. */
430 	uid_init();
431 
432 	/* Charge root for one process. */
433 	(void)chgproccnt(0, 1);
434 
435 	/* Initialize the run queues, turnstiles and sleep queues. */
436 	sched_rqinit();
437 	turnstile_init();
438 	sleeptab_init(&sleeptab);
439 
440 	sched_init();
441 
442 	/* Initialize processor-sets */
443 	psets_init();
444 
445 	/* Initialize cpufreq(9) */
446 	cpufreq_init();
447 
448 	/* MI initialization of the boot cpu */
449 	error = mi_cpu_attach(curcpu());
450 	KASSERT(error == 0);
451 
452 	/* Initialize timekeeping. */
453 	time_init();
454 
455 	/*
456 	 * Initialize mbuf's.  Do this now because we might attempt to
457 	 * allocate mbufs or mbuf clusters during autoconfiguration.
458 	 */
459 	mbinit();
460 
461 	/* Initialize I/O statistics. */
462 	iostat_init();
463 
464 	/* Initialize the log device. */
465 	loginit();
466 
467 	/* Second part of module system initialization. */
468 	module_start_unload_thread();
469 
470 	/* Initialize autoconf data structures before any modules are loaded */
471 	config_init_mi();
472 
473 	/* Initialize the file systems. */
474 #ifdef NVNODE_IMPLICIT
475 	/*
476 	 * If maximum number of vnodes in namei vnode cache is not explicitly
477 	 * defined in kernel config, adjust the number such as we use roughly
478 	 * 10% of memory for vnodes and associated data structures in the
479 	 * assumed worst case.  Do not provide fewer than NVNODE vnodes.
480 	 */
481 	usevnodes = calc_cache_size(vmem_size(kmem_arena, VMEM_FREE|VMEM_ALLOC),
482 	    10, VNODE_KMEM_MAXPCT) / VNODE_COST;
483 	if (usevnodes > desiredvnodes)
484 		desiredvnodes = usevnodes;
485 #endif /* NVNODE_IMPLICIT */
486 #ifdef MAXFILES_IMPLICIT
487 	/*
488 	 * If maximum number of files is not explicitly defined in
489 	 * kernel config, adjust the number so that it is somewhat
490 	 * more reasonable on machines with larger memory sizes.
491 	 * Arbitary numbers are 20,000 files for 16GB RAM or more
492 	 * and 10,000 files for 1GB RAM or more.
493 	 *
494 	 * XXXtodo: adjust this and other values totally dynamically
495 	 */
496 	if (ctob((uint64_t)physmem) >= 16ULL * 1024 * 1024 * 1024)
497 		maxfiles = MAX(maxfiles, 20000);
498 	if (ctob((uint64_t)physmem) >= 1024 * 1024 * 1024)
499 		maxfiles = MAX(maxfiles, 10000);
500 #endif /* MAXFILES_IMPLICIT */
501 
502 	/* Initialize fstrans. */
503 	fstrans_init();
504 
505 	vfsinit();
506 	lf_init();
507 
508 	/* Initialize the file descriptor system. */
509 	fd_sys_init();
510 
511 	/* Initialize cwd structures */
512 	cwd_sys_init();
513 
514 	/* Initialize kqueue. */
515 	kqueue_init();
516 
517 	inittimecounter();
518 	ntp_init();
519 
520 	/* Initialize tty subsystem. */
521 	tty_init();
522 	ttyldisc_init();
523 
524 	/* Initialize the buffer cache, part 2. */
525 	bufinit2();
526 
527 	/* Initialize the disk wedge subsystem. */
528 	dkwedge_init();
529 
530 	/* Initialize pfil */
531 	pfil_init();
532 
533 	/* Initialize interfaces. */
534 	ifinit1();
535 
536 	spldebug_start();
537 
538 	/* Initialize sockets thread(s) */
539 	soinit1();
540 
541 	/*
542 	 * Initialize the bufq strategy sub-system and any built-in
543 	 * strategy modules - they may be needed by some devices during
544 	 * auto-configuration
545 	 */
546 	bufq_init();
547 	module_init_class(MODULE_CLASS_BUFQ);
548 
549 	/* Configure the system hardware.  This will enable interrupts. */
550 	configure();
551 #ifdef __HAVE_LEGACY_INTRCNT
552 	evcnt_attach_legacy_intrcnt();
553 #endif
554 
555 	/* Once all CPUs are detected, initialize the per-CPU cprng_fast.  */
556 	cprng_fast_init();
557 
558 	ssp_init();
559 
560 	ubc_init();		/* must be after autoconfig */
561 
562 	mm_init();
563 
564 	configure2();
565 
566 	/* Initialize the rest of ipi(9) after CPUs have been detected. */
567 	ipi_percpu_init();
568 
569 	futex_sys_init();
570 
571 	/* Now timer is working.  Enable preemption. */
572 	kpreempt_enable();
573 
574 	/* Get the threads going and into any sleeps before continuing. */
575 	yield();
576 
577 	/* Enable deferred processing of RNG samples */
578 	rnd_init_softint();
579 
580 	vmem_rehash_start();	/* must be before exec_init */
581 
582 	/* Initialize exec structures */
583 	exec_init(1);		/* seminit calls exithook_establish() */
584 
585 #if NVERIEXEC > 0
586 	/*
587 	 * Initialise the Veriexec subsystem.
588 	 */
589 	veriexec_init();
590 #endif /* NVERIEXEC > 0 */
591 
592 	pax_init();
593 
594 #ifdef	IPSEC
595 	/* Attach network crypto subsystem */
596 	ipsec_attach();
597 #endif
598 
599 	/*
600 	 * Initialize protocols.  Block reception of incoming packets
601 	 * until everything is ready.
602 	 */
603 	s = splnet();
604 	ifinit();
605 #if defined(INET) || defined(INET6)
606 	lltableinit();
607 #endif
608 	domaininit(true);
609 	ifinit_post();
610 	if_attachdomain();
611 	splx(s);
612 
613 #ifdef GPROF
614 	/* Initialize kernel profiling. */
615 	kmstartup();
616 #endif
617 
618 	/* Initialize system accounting. */
619 	acct_init();
620 
621 #ifndef PIPE_SOCKETPAIR
622 	/* Initialize pipes. */
623 	pipe_init();
624 #endif
625 
626 #ifdef KTRACE
627 	/* Initialize ktrace. */
628 	ktrinit();
629 #endif
630 
631 	machdep_init();
632 
633 	procinit_sysctl();
634 
635 	scdebug_init();
636 
637 	/*
638 	 * Create process 1 (init(8)).  We do this now, as Unix has
639 	 * historically had init be process 1, and changing this would
640 	 * probably upset a lot of people.
641 	 *
642 	 * Note that process 1 won't immediately exec init(8), but will
643 	 * wait for us to inform it that the root file system has been
644 	 * mounted.
645 	 */
646 	if (fork1(l, 0, SIGCHLD, NULL, 0, start_init, NULL, NULL))
647 		panic("fork init");
648 
649 	/*
650 	 * The initproc variable cannot be initialized in start_init as there
651 	 * is a race between vfs_mountroot and start_init.
652 	 */
653 	mutex_enter(&proc_lock);
654 	initproc = proc_find_raw(1);
655 	mutex_exit(&proc_lock);
656 
657 	/*
658 	 * Load any remaining builtin modules, and hand back temporary
659 	 * storage to the VM system.  Then require force when loading any
660 	 * remaining un-init'ed built-in modules to avoid later surprises.
661 	 */
662 	module_init_class(MODULE_CLASS_ANY);
663 	module_builtin_require_force();
664 
665 	/*
666 	 * Finalize configuration now that all real devices have been
667 	 * found.  This needs to be done before the root device is
668 	 * selected, since finalization may create the root device.
669 	 */
670 	config_finalize();
671 
672 	sysctl_finalize();
673 
674 	/*
675 	 * Now that autoconfiguration has completed, we can determine
676 	 * the root and dump devices.
677 	 */
678 	cpu_rootconf();
679 	cpu_dumpconf();
680 
681 	/* Mount the root file system. */
682 	do {
683 		domountroothook(root_device);
684 		if ((error = vfs_mountroot())) {
685 			printf("cannot mount root, error = %d\n", error);
686 			boothowto |= RB_ASKNAME;
687 			setroot(root_device,
688 			    (rootdev != NODEV) ? DISKPART(rootdev) : 0);
689 		}
690 	} while (error != 0);
691 	mountroothook_destroy();
692 
693 	configure3();
694 
695 	/*
696 	 * Initialise the time-of-day clock, passing the time recorded
697 	 * in the root filesystem (if any) for use by systems that
698 	 * don't have a non-volatile time-of-day device.
699 	 */
700 	inittodr(rootfstime);
701 
702 	/*
703 	 * Now can look at time, having had a chance to verify the time
704 	 * from the file system.  Reset l->l_rtime as it may have been
705 	 * munched in mi_switch() after the time got set.
706 	 */
707 	getnanotime(&time);
708 
709 	mutex_enter(&proc_lock);
710 	LIST_FOREACH(p, &allproc, p_list) {
711 		KASSERT((p->p_flag & PK_MARKER) == 0);
712 		mutex_enter(p->p_lock);
713 		TIMESPEC_TO_TIMEVAL(&p->p_stats->p_start, &time);
714 		LIST_FOREACH(l, &p->p_lwps, l_sibling) {
715 			lwp_lock(l);
716 			memset(&l->l_rtime, 0, sizeof(l->l_rtime));
717 			lwp_unlock(l);
718 		}
719 		mutex_exit(p->p_lock);
720 	}
721 	mutex_exit(&proc_lock);
722 	binuptime(&curlwp->l_stime);
723 
724 	for (CPU_INFO_FOREACH(cii, ci)) {
725 		ci->ci_schedstate.spc_lastmod = time_second;
726 	}
727 
728 	/* Create the pageout daemon kernel thread. */
729 	uvm_swap_init();
730 	if (kthread_create(PRI_PGDAEMON, KTHREAD_MPSAFE, NULL, uvm_pageout,
731 	    NULL, NULL, "pgdaemon"))
732 		panic("fork pagedaemon");
733 
734 	/* Create the filesystem syncer kernel thread. */
735 	if (kthread_create(PRI_IOFLUSH, KTHREAD_MPSAFE, NULL, sched_sync,
736 	    NULL, NULL, "ioflush"))
737 		panic("fork syncer");
738 
739 	/* Wait for final configure threads to complete. */
740 	config_finalize_mountroot();
741 
742 	/*
743 	 * Okay, now we can let init(8) exec!  It's off to userland!
744 	 */
745 	mutex_enter(&proc_lock);
746 	start_init_exec = 1;
747 	cv_broadcast(&lbolt);
748 	mutex_exit(&proc_lock);
749 
750 	/* The scheduler is an infinite loop. */
751 	uvm_scheduler();
752 	/* NOTREACHED */
753 }
754 
755 /*
756  * Configure the system's hardware.
757  */
758 static void
759 configure(void)
760 {
761 
762 	/*
763 	 * XXX
764 	 * callout_setfunc() requires mutex(9) so it can't be in config_init()
765 	 * on amiga and atari which use config_init() and autoconf(9) fucntions
766 	 * to initialize console devices.
767 	 */
768 	config_twiddle_init();
769 
770 	pmf_init();
771 
772 	/* Initialize driver modules */
773 	module_init_class(MODULE_CLASS_DRIVER);
774 
775 	userconf_init();
776 	if (boothowto & RB_USERCONF)
777 		userconf_prompt();
778 
779 	if ((boothowto & (AB_SILENT|AB_VERBOSE)) == AB_SILENT) {
780 		printf_nolog("Detecting hardware...");
781 	}
782 
783 	/*
784 	 * Do the machine-dependent portion of autoconfiguration.  This
785 	 * sets the configuration machinery here in motion by "finding"
786 	 * the root bus.  When this function returns, we expect interrupts
787 	 * to be enabled.
788 	 */
789 	cpu_configure();
790 }
791 
792 static void
793 configure2(void)
794 {
795 	CPU_INFO_ITERATOR cii;
796 	struct cpu_info *ci;
797 	int s;
798 
799 	/* Fix up CPU topology info, which has all been collected by now. */
800 	cpu_topology_init();
801 
802 	/*
803 	 * Now that we've found all the hardware, start the real time
804 	 * and statistics clocks.
805 	 */
806 	initclocks();
807 
808 	cold = 0;	/* clocks are running, we're warm now! */
809 	s = splsched();
810 	curcpu()->ci_schedstate.spc_flags |= SPCF_RUNNING;
811 	splx(s);
812 
813 	/* Setup the runqueues and scheduler. */
814 	runq_init();
815 	synch_init();
816 
817 	/* Boot the secondary processors. */
818 	for (CPU_INFO_FOREACH(cii, ci)) {
819 		uvm_cpu_attach(ci);
820 	}
821 
822 	/* Decide how to partition free memory. */
823 	uvm_page_rebucket();
824 
825 	mp_online = true;
826 #if defined(MULTIPROCESSOR)
827 	cpu_boot_secondary_processors();
828 #endif
829 
830 	/*
831 	 * Bus scans can make it appear as if the system has paused, so
832 	 * twiddle constantly while config_interrupts() jobs are running.
833 	 */
834 	config_twiddle_fn(NULL);
835 
836 	/*
837 	 * Create threads to call back and finish configuration for
838 	 * devices that want interrupts enabled.
839 	 */
840 	config_create_interruptthreads();
841 }
842 
843 static void
844 configure3(void)
845 {
846 
847 	/*
848 	 * Create threads to call back and finish configuration for
849 	 * devices that want the mounted root file system.
850 	 */
851 	config_create_mountrootthreads();
852 
853 	/* Get the threads going and into any sleeps before continuing. */
854 	yield();
855 }
856 
857 static void
858 rootconf_handle_wedges(void)
859 {
860 	struct disklabel label;
861 	struct partition *p;
862 	struct vnode *vp;
863 	daddr_t startblk;
864 	uint64_t nblks;
865 	device_t dev;
866 	int error;
867 
868 	if (booted_nblks) {
869 		/*
870 		 * bootloader passed geometry
871 		 */
872 		dev      = booted_device;
873 		startblk = booted_startblk;
874 		nblks    = booted_nblks;
875 
876 		/*
877 		 * keep booted_device and booted_partition
878 		 * in case the kernel doesn't identify a wedge
879 		 */
880 	} else {
881 		/*
882 		 * bootloader passed partition number
883 		 *
884 		 * We cannot ask the partition device directly when it is
885 		 * covered by a wedge. Instead we look up the geometry in
886 		 * the disklabel.
887 		 */
888 		vp = opendisk(booted_device);
889 
890 		if (vp == NULL)
891 			return;
892 
893 		error = VOP_IOCTL(vp, DIOCGDINFO, &label, FREAD, NOCRED);
894 		VOP_CLOSE(vp, FREAD, NOCRED);
895 		vput(vp);
896 		if (error)
897 			return;
898 
899 		KASSERT(booted_partition >= 0
900 			&& booted_partition < MAXPARTITIONS);
901 
902 		p = &label.d_partitions[booted_partition];
903 
904 		dev      = booted_device;
905 		startblk = p->p_offset;
906 		nblks    = p->p_size;
907 	}
908 
909 	dev = dkwedge_find_partition(dev, startblk, nblks);
910 	if (dev != NULL) {
911 		booted_device = dev;
912 		booted_partition = 0;
913 	}
914 }
915 
916 void
917 rootconf(void)
918 {
919 	if (booted_device != NULL)
920 		rootconf_handle_wedges();
921 
922 	setroot(booted_device, booted_partition);
923 }
924 
925 static void
926 check_console(struct lwp *l)
927 {
928 	struct vnode *vp;
929 	int error;
930 
931 	error = namei_simple_kernel("/dev/console",
932 				NSM_FOLLOW_NOEMULROOT, &vp);
933 	if (error == 0) {
934 		vrele(vp);
935 	} else if (error == ENOENT) {
936 		if (boothowto & (AB_VERBOSE|AB_DEBUG))
937 			printf("warning: no /dev/console\n");
938 	} else {
939 		printf("warning: lookup /dev/console: error %d\n", error);
940 	}
941 }
942 
943 /*
944  * List of paths to try when searching for "init".
945  */
946 static const char * const initpaths[] = {
947 	"/sbin/init",
948 	"/sbin/oinit",
949 	"/sbin/init.bak",
950 	"/rescue/init",
951 	NULL,
952 };
953 
954 /*
955  * Start the initial user process; try exec'ing each pathname in "initpaths".
956  * The program is invoked with one argument containing the boot flags.
957  */
958 static void
959 start_init(void *arg)
960 {
961 	struct lwp *l = arg;
962 	struct proc *p = l->l_proc;
963 	vaddr_t addr;
964 	struct sys_execve_args /* {
965 		syscallarg(const char *) path;
966 		syscallarg(char * const *) argp;
967 		syscallarg(char * const *) envp;
968 	} */ args;
969 	int options, i, error;
970 	register_t retval[2];
971 	char flags[4], *flagsp;
972 	const char *path, *slash;
973 	char *ucp, **uap, *arg0, *arg1, *argv[3];
974 	char ipath[129];
975 	int ipx, len;
976 
977 	/*
978 	 * Now in process 1.
979 	 */
980 	strncpy(p->p_comm, "init", MAXCOMLEN);
981 
982 	/*
983 	 * Wait for main() to tell us that it's safe to exec.
984 	 */
985 	mutex_enter(&proc_lock);
986 	while (start_init_exec == 0)
987 		cv_wait(&lbolt, &proc_lock);
988 	mutex_exit(&proc_lock);
989 
990 	/*
991 	 * This is not the right way to do this.  We really should
992 	 * hand-craft a descriptor onto /dev/console to hand to init,
993 	 * but that's a _lot_ more work, and the benefit from this easy
994 	 * hack makes up for the "good is the enemy of the best" effect.
995 	 */
996 	check_console(l);
997 
998 	/*
999 	 * Need just enough stack to hold the faked-up "execve()" arguments.
1000 	 */
1001 	addr = (vaddr_t)STACK_ALLOC(USRSTACK, PAGE_SIZE);
1002 	if (uvm_map(&p->p_vmspace->vm_map, &addr, PAGE_SIZE,
1003 	    NULL, UVM_UNKNOWN_OFFSET, 0,
1004 	    UVM_MAPFLAG(UVM_PROT_RW, UVM_PROT_RW, UVM_INH_COPY,
1005 	    UVM_ADV_NORMAL,
1006 	    UVM_FLAG_FIXED|UVM_FLAG_OVERLAY|UVM_FLAG_COPYONW)) != 0)
1007 		panic("init: couldn't allocate argument space");
1008 	p->p_vmspace->vm_maxsaddr = (void *)STACK_MAX(addr, PAGE_SIZE);
1009 
1010 	ipx = 0;
1011 	while (1) {
1012 		if (boothowto & RB_ASKNAME) {
1013 			printf("init path");
1014 			if (initpaths[ipx])
1015 				printf(" (default %s)", initpaths[ipx]);
1016 			printf(": ");
1017 			len = cngetsn(ipath, sizeof(ipath)-1);
1018 			if (len == 4 && strcmp(ipath, "halt") == 0) {
1019 				kern_reboot(RB_HALT, NULL);
1020 			} else if (len == 6 && strcmp(ipath, "reboot") == 0) {
1021 				kern_reboot(0, NULL);
1022 #if defined(DDB)
1023 			} else if (len == 3 && strcmp(ipath, "ddb") == 0) {
1024 				console_debugger();
1025 				continue;
1026 #endif
1027 			} else if (len > 0 && ipath[0] == '/') {
1028 				ipath[len] = '\0';
1029 				path = ipath;
1030 			} else if (len == 0 && initpaths[ipx] != NULL) {
1031 				path = initpaths[ipx++];
1032 			} else {
1033 				printf("use absolute path, ");
1034 #if defined(DDB)
1035 				printf("\"ddb\", ");
1036 #endif
1037 				printf("\"halt\", or \"reboot\"\n");
1038 				continue;
1039 			}
1040 		} else {
1041 			if ((path = initpaths[ipx++]) == NULL) {
1042 				ipx = 0;
1043 				boothowto |= RB_ASKNAME;
1044 				continue;
1045 			}
1046 		}
1047 
1048 		ucp = (char *)USRSTACK;
1049 
1050 		/*
1051 		 * Construct the boot flag argument.
1052 		 */
1053 		flagsp = flags;
1054 		*flagsp++ = '-';
1055 		options = 0;
1056 
1057 		if (boothowto & RB_SINGLE) {
1058 			*flagsp++ = 's';
1059 			options = 1;
1060 		}
1061 #ifdef notyet
1062 		if (boothowto & RB_FASTBOOT) {
1063 			*flagsp++ = 'f';
1064 			options = 1;
1065 		}
1066 #endif
1067 
1068 		/*
1069 		 * Move out the flags (arg 1), if necessary.
1070 		 */
1071 		if (options != 0) {
1072 			*flagsp++ = '\0';
1073 			i = flagsp - flags;
1074 #ifdef DEBUG
1075 			aprint_normal("init: copying out flags `%s' %d\n", flags, i);
1076 #endif
1077 			arg1 = STACK_ALLOC(ucp, i);
1078 			ucp = STACK_MAX(arg1, i);
1079 			if ((error = copyout((void *)flags, arg1, i)) != 0)
1080 				goto copyerr;
1081 		} else
1082 			arg1 = NULL;
1083 
1084 		/*
1085 		 * Move out the file name (also arg 0).
1086 		 */
1087 		i = strlen(path) + 1;
1088 #ifdef DEBUG
1089 		aprint_normal("init: copying out path `%s' %d\n", path, i);
1090 #else
1091 		if (boothowto & RB_ASKNAME || path != initpaths[0])
1092 			printf("init: trying %s\n", path);
1093 #endif
1094 		arg0 = STACK_ALLOC(ucp, i);
1095 		ucp = STACK_MAX(arg0, i);
1096 		if ((error = copyout(path, arg0, i)) != 0)
1097 			goto copyerr;
1098 
1099 		/*
1100 		 * Move out the arg pointers.
1101 		 */
1102 		ucp = (void *)STACK_ALIGN(ucp, STACK_ALIGNBYTES);
1103 		uap = (char **)STACK_ALLOC(ucp, sizeof(argv));
1104 		SCARG(&args, path) = arg0;
1105 		SCARG(&args, argp) = uap;
1106 		SCARG(&args, envp) = NULL;
1107 		slash = strrchr(path, '/');
1108 
1109 		argv[0] = slash ? arg0 + (slash + 1 - path) : arg0;
1110 		argv[1] = arg1;
1111 		argv[2] = NULL;
1112 		if ((error = copyout(argv, uap, sizeof(argv))) != 0)
1113 			goto copyerr;
1114 
1115 		/*
1116 		 * Now try to exec the program.  If it can't for any reason
1117 		 * other than it doesn't exist, complain.
1118 		 */
1119 		error = sys_execve(l, &args, retval);
1120 		if (error == 0 || error == EJUSTRETURN) {
1121 			KERNEL_UNLOCK_LAST(l);
1122 			return;
1123 		}
1124 		printf("exec %s: error %d\n", path, error);
1125 	}
1126 	printf("init: not found\n");
1127 	panic("no init");
1128 copyerr:
1129 	panic("copyout %d", error);
1130 }
1131 
1132 /*
1133  * calculate cache size (in bytes) from physmem and vsize.
1134  */
1135 vaddr_t
1136 calc_cache_size(vsize_t vsize, int pct, int va_pct)
1137 {
1138 	paddr_t t;
1139 
1140 	/* XXX should consider competing cache if any */
1141 	/* XXX should consider submaps */
1142 	t = (uintmax_t)physmem * pct / 100 * PAGE_SIZE;
1143 	if (vsize != 0) {
1144 		vsize = (uintmax_t)vsize * va_pct / 100;
1145 		if (t > vsize) {
1146 			t = vsize;
1147 		}
1148 	}
1149 	return t;
1150 }
1151 
1152 /*
1153  * Print the system start up banner.
1154  *
1155  * - Print a limited banner if AB_SILENT.
1156  * - Always send normal banner to the log.
1157  */
1158 #define MEM_PBUFSIZE	sizeof("99999 MB")
1159 
1160 void
1161 banner(void)
1162 {
1163 	static char notice[] = " Notice: this software is "
1164 	    "protected by copyright";
1165 	char pbuf[81];
1166 	void (*pr)(const char *, ...) __printflike(1, 2);
1167 	int i;
1168 
1169 	if ((boothowto & AB_SILENT) != 0) {
1170 		snprintf(pbuf, sizeof(pbuf), "%s %s (%s)",
1171 		    ostype, osrelease, kernel_ident);
1172 		printf_nolog("%s", pbuf);
1173 		for (i = 80 - strlen(pbuf) - sizeof(notice); i > 0; i--)
1174 			printf(" ");
1175 		printf_nolog("%s\n", notice);
1176 		pr = aprint_normal;
1177 	} else {
1178 		pr = printf;
1179 	}
1180 
1181 	memset(pbuf, 0, sizeof(pbuf));
1182 	(*pr)("%s%s", copyright, version);
1183 	format_bytes(pbuf, MEM_PBUFSIZE, ctob((uint64_t)physmem));
1184 	(*pr)("total memory = %s\n", pbuf);
1185 	format_bytes(pbuf, MEM_PBUFSIZE, ctob((uint64_t)uvm_availmem(false)));
1186 	(*pr)("avail memory = %s\n", pbuf);
1187 }
1188