1/*-
2 * Copyright (c) 2010 Marcel Moolenaar
3 * Copyright (c) 1999-2004 Poul-Henning Kamp
4 * Copyright (c) 1999 Michael Smith
5 * Copyright (c) 1989, 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 * 4. Neither the name of the University nor the names of its contributors
22 * may be used to endorse or promote products derived from this software
23 * without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 * SUCH DAMAGE.
36 */
37
38#include "opt_rootdevname.h"
39
40#include <sys/cdefs.h>
41__FBSDID("$FreeBSD: head/sys/kern/vfs_mountroot.c 253847 2013-07-31 19:14:00Z ian $");
42
43#include <sys/param.h>
44#include <sys/conf.h>
45#include <sys/cons.h>
46#include <sys/fcntl.h>
47#include <sys/jail.h>
48#include <sys/kernel.h>
49#include <sys/malloc.h>
50#include <sys/mdioctl.h>
51#include <sys/mount.h>
52#include <sys/mutex.h>
53#include <sys/namei.h>
54#include <sys/priv.h>
55#include <sys/proc.h>
56#include <sys/filedesc.h>
57#include <sys/reboot.h>
58#include <sys/sbuf.h>
59#include <sys/stat.h>
60#include <sys/syscallsubr.h>
61#include <sys/sysproto.h>
62#include <sys/sx.h>
63#include <sys/sysctl.h>
64#include <sys/sysent.h>
65#include <sys/systm.h>
66#include <sys/vnode.h>
67
68#include <geom/geom.h>
69
70/*
71 * The root filesystem is detailed in the kernel environment variable
72 * vfs.root.mountfrom, which is expected to be in the general format
73 *
74 * <vfsname>:[<path>][ <vfsname>:[<path>] ...]
75 * vfsname := the name of a VFS known to the kernel and capable
76 * of being mounted as root
77 * path := disk device name or other data used by the filesystem
78 * to locate its physical store
79 *
80 * If the environment variable vfs.root.mountfrom is a space separated list,
81 * each list element is tried in turn and the root filesystem will be mounted
82 * from the first one that suceeds.
83 *
84 * The environment variable vfs.root.mountfrom.options is a comma delimited
85 * set of string mount options. These mount options must be parseable
86 * by nmount() in the kernel.
87 */
88
89static int parse_mount(char **);
90static struct mntarg *parse_mountroot_options(struct mntarg *, const char *);
91
92/*
93 * The vnode of the system's root (/ in the filesystem, without chroot
94 * active.)
95 */
96struct vnode *rootvnode;
97
98char *rootdevnames[2] = {NULL, NULL};
99
100struct root_hold_token {
101 const char *who;
102 LIST_ENTRY(root_hold_token) list;
103};
104
105static LIST_HEAD(, root_hold_token) root_holds =
106 LIST_HEAD_INITIALIZER(root_holds);
107
108enum action {
109 A_CONTINUE,
110 A_PANIC,
111 A_REBOOT,
112 A_RETRY
113};
114
115static enum action root_mount_onfail = A_CONTINUE;
116
117static int root_mount_mddev;
118static int root_mount_complete;
119
120/* By default wait up to 3 seconds for devices to appear. */
121static int root_mount_timeout = 3;
122
123struct root_hold_token *
124root_mount_hold(const char *identifier)
125{
126 struct root_hold_token *h;
127
128 if (root_mounted())
129 return (NULL);
130
131 h = malloc(sizeof *h, M_DEVBUF, M_ZERO | M_WAITOK);
132 h->who = identifier;
133 mtx_lock(&mountlist_mtx);
134 LIST_INSERT_HEAD(&root_holds, h, list);
135 mtx_unlock(&mountlist_mtx);
136 return (h);
137}
138
139void
140root_mount_rel(struct root_hold_token *h)
141{
142
143 if (h == NULL)
144 return;
145 mtx_lock(&mountlist_mtx);
146 LIST_REMOVE(h, list);
147 wakeup(&root_holds);
148 mtx_unlock(&mountlist_mtx);
149 free(h, M_DEVBUF);
150}
151
152int
153root_mounted(void)
154{
155
156 /* No mutex is acquired here because int stores are atomic. */
157 return (root_mount_complete);
158}
159
160void
161root_mount_wait(void)
162{
163
164 /*
165 * Panic on an obvious deadlock - the function can't be called from
166 * a thread which is doing the whole SYSINIT stuff.
167 */
168 KASSERT(curthread->td_proc->p_pid != 0,
169 ("root_mount_wait: cannot be called from the swapper thread"));
170 mtx_lock(&mountlist_mtx);
171 while (!root_mount_complete) {
172 msleep(&root_mount_complete, &mountlist_mtx, PZERO, "rootwait",
173 hz);
174 }
175 mtx_unlock(&mountlist_mtx);
176}
177
178static void
179set_rootvnode(void)
180{
181 struct proc *p;
182
183 if (VFS_ROOT(TAILQ_FIRST(&mountlist), LK_EXCLUSIVE, &rootvnode))
184 panic("Cannot find root vnode");
185
186 VOP_UNLOCK(rootvnode, 0);
187
188 p = curthread->td_proc;
189 FILEDESC_XLOCK(p->p_fd);
190
191 if (p->p_fd->fd_cdir != NULL)
192 vrele(p->p_fd->fd_cdir);
193 p->p_fd->fd_cdir = rootvnode;
194 VREF(rootvnode);
195
196 if (p->p_fd->fd_rdir != NULL)
197 vrele(p->p_fd->fd_rdir);
198 p->p_fd->fd_rdir = rootvnode;
199 VREF(rootvnode);
200
201 FILEDESC_XUNLOCK(p->p_fd);
202}
203
204static int
205vfs_mountroot_devfs(struct thread *td, struct mount **mpp)
206{
207 struct vfsoptlist *opts;
208 struct vfsconf *vfsp;
209 struct mount *mp;
210 int error;
211
212 *mpp = NULL;
213
214 vfsp = vfs_byname("devfs");
215 KASSERT(vfsp != NULL, ("Could not find devfs by name"));
216 if (vfsp == NULL)
217 return (ENOENT);
218
219 mp = vfs_mount_alloc(NULLVP, vfsp, "/dev", td->td_ucred);
220
221 error = VFS_MOUNT(mp);
222 KASSERT(error == 0, ("VFS_MOUNT(devfs) failed %d", error));
223 if (error)
224 return (error);
225
226 opts = malloc(sizeof(struct vfsoptlist), M_MOUNT, M_WAITOK);
227 TAILQ_INIT(opts);
228 mp->mnt_opt = opts;
229
230 mtx_lock(&mountlist_mtx);
231 TAILQ_INSERT_HEAD(&mountlist, mp, mnt_list);
232 mtx_unlock(&mountlist_mtx);
233
234 *mpp = mp;
235 set_rootvnode();
236
237 error = kern_symlink(td, "/", "dev", UIO_SYSSPACE);
238 if (error)
239 printf("kern_symlink /dev -> / returns %d\n", error);
240
241 return (error);
242}
243
244static int
245vfs_mountroot_shuffle(struct thread *td, struct mount *mpdevfs)
246{
247 struct nameidata nd;
248 struct mount *mporoot, *mpnroot;
249 struct vnode *vp, *vporoot, *vpdevfs;
250 char *fspath;
251 int error;
252
253 mpnroot = TAILQ_NEXT(mpdevfs, mnt_list);
254
255 /* Shuffle the mountlist. */
256 mtx_lock(&mountlist_mtx);
257 mporoot = TAILQ_FIRST(&mountlist);
258 TAILQ_REMOVE(&mountlist, mpdevfs, mnt_list);
259 if (mporoot != mpdevfs) {
260 TAILQ_REMOVE(&mountlist, mpnroot, mnt_list);
261 TAILQ_INSERT_HEAD(&mountlist, mpnroot, mnt_list);
262 }
263 TAILQ_INSERT_TAIL(&mountlist, mpdevfs, mnt_list);
264 mtx_unlock(&mountlist_mtx);
265
266 cache_purgevfs(mporoot);
267 if (mporoot != mpdevfs)
268 cache_purgevfs(mpdevfs);
269
270 VFS_ROOT(mporoot, LK_EXCLUSIVE, &vporoot);
271
272 VI_LOCK(vporoot);
273 vporoot->v_iflag &= ~VI_MOUNT;
274 VI_UNLOCK(vporoot);
275 vporoot->v_mountedhere = NULL;
276 mporoot->mnt_flag &= ~MNT_ROOTFS;
277 mporoot->mnt_vnodecovered = NULL;
278 vput(vporoot);
279
280 /* Set up the new rootvnode, and purge the cache */
281 mpnroot->mnt_vnodecovered = NULL;
282 set_rootvnode();
283 cache_purgevfs(rootvnode->v_mount);
284
285 if (mporoot != mpdevfs) {
286 /* Remount old root under /.mount or /mnt */
287 fspath = "/.mount";
288 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE,
289 fspath, td);
290 error = namei(&nd);
291 if (error) {
292 NDFREE(&nd, NDF_ONLY_PNBUF);
293 fspath = "/mnt";
294 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE,
295 fspath, td);
296 error = namei(&nd);
297 }
298 if (!error) {
299 vp = nd.ni_vp;
300 error = (vp->v_type == VDIR) ? 0 : ENOTDIR;
301 if (!error)
302 error = vinvalbuf(vp, V_SAVE, 0, 0);
303 if (!error) {
304 cache_purge(vp);
305 mporoot->mnt_vnodecovered = vp;
306 vp->v_mountedhere = mporoot;
307 strlcpy(mporoot->mnt_stat.f_mntonname,
308 fspath, MNAMELEN);
309 VOP_UNLOCK(vp, 0);
310 } else
311 vput(vp);
312 }
313 NDFREE(&nd, NDF_ONLY_PNBUF);
314
315 if (error && bootverbose)
316 printf("mountroot: unable to remount previous root "
317 "under /.mount or /mnt (error %d).\n", error);
318 }
319
320 /* Remount devfs under /dev */
321 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, "/dev", td);
322 error = namei(&nd);
323 if (!error) {
324 vp = nd.ni_vp;
325 error = (vp->v_type == VDIR) ? 0 : ENOTDIR;
326 if (!error)
327 error = vinvalbuf(vp, V_SAVE, 0, 0);
328 if (!error) {
329 vpdevfs = mpdevfs->mnt_vnodecovered;
330 if (vpdevfs != NULL) {
331 cache_purge(vpdevfs);
332 vpdevfs->v_mountedhere = NULL;
333 vrele(vpdevfs);
334 }
335 mpdevfs->mnt_vnodecovered = vp;
336 vp->v_mountedhere = mpdevfs;
337 VOP_UNLOCK(vp, 0);
338 } else
339 vput(vp);
340 }
341 if (error && bootverbose)
342 printf("mountroot: unable to remount devfs under /dev "
343 "(error %d).\n", error);
344 NDFREE(&nd, NDF_ONLY_PNBUF);
345
346 if (mporoot == mpdevfs) {
347 vfs_unbusy(mpdevfs);
348 /* Unlink the no longer needed /dev/dev -> / symlink */
349 error = kern_unlink(td, "/dev/dev", UIO_SYSSPACE);
350 if (error && bootverbose)
351 printf("mountroot: unable to unlink /dev/dev "
352 "(error %d)\n", error);
353 }
354
355 return (0);
356}
357
358/*
359 * Configuration parser.
360 */
361
362/* Parser character classes. */
363#define CC_WHITESPACE -1
364#define CC_NONWHITESPACE -2
365
366/* Parse errors. */
367#define PE_EOF -1
368#define PE_EOL -2
369
370static __inline int
371parse_peek(char **conf)
372{
373
374 return (**conf);
375}
376
377static __inline void
378parse_poke(char **conf, int c)
379{
380
381 **conf = c;
382}
383
384static __inline void
385parse_advance(char **conf)
386{
387
388 (*conf)++;
389}
390
391static __inline int
392parse_isspace(int c)
393{
394
395 return ((c == ' ' || c == '\t' || c == '\n') ? 1 : 0);
396}
397
398static int
399parse_skipto(char **conf, int mc)
400{
401 int c, match;
402
403 while (1) {
404 c = parse_peek(conf);
405 if (c == 0)
406 return (PE_EOF);
407 switch (mc) {
408 case CC_WHITESPACE:
409 match = (c == ' ' || c == '\t' || c == '\n') ? 1 : 0;
410 break;
411 case CC_NONWHITESPACE:
412 if (c == '\n')
413 return (PE_EOL);
414 match = (c != ' ' && c != '\t') ? 1 : 0;
415 break;
416 default:
417 match = (c == mc) ? 1 : 0;
418 break;
419 }
420 if (match)
421 break;
422 parse_advance(conf);
423 }
424 return (0);
425}
426
427static int
428parse_token(char **conf, char **tok)
429{
430 char *p;
431 size_t len;
432 int error;
433
434 *tok = NULL;
435 error = parse_skipto(conf, CC_NONWHITESPACE);
436 if (error)
437 return (error);
438 p = *conf;
439 error = parse_skipto(conf, CC_WHITESPACE);
440 len = *conf - p;
441 *tok = malloc(len + 1, M_TEMP, M_WAITOK | M_ZERO);
442 bcopy(p, *tok, len);
443 return (0);
444}
445
446static void
447parse_dir_ask_printenv(const char *var)
448{
449 char *val;
450
451 val = getenv(var);
452 if (val != NULL) {
453 printf(" %s=%s\n", var, val);
454 freeenv(val);
455 }
456}
457
458static int
459parse_dir_ask(char **conf)
460{
461 char name[80];
462 char *mnt;
463 int error;
464
465 printf("\nLoader variables:\n");
466 parse_dir_ask_printenv("vfs.root.mountfrom");
467 parse_dir_ask_printenv("vfs.root.mountfrom.options");
468
469 printf("\nManual root filesystem specification:\n");
470 printf(" <fstype>:<device> [options]\n");
471 printf(" Mount <device> using filesystem <fstype>\n");
472 printf(" and with the specified (optional) option list.\n");
473 printf("\n");
474 printf(" eg. ufs:/dev/da0s1a\n");
475 printf(" zfs:tank\n");
476 printf(" cd9660:/dev/acd0 ro\n");
477 printf(" (which is equivalent to: ");
478 printf("mount -t cd9660 -o ro /dev/acd0 /)\n");
479 printf("\n");
480 printf(" ? List valid disk boot devices\n");
481 printf(" . Yield 1 second (for background tasks)\n");
482 printf(" <empty line> Abort manual input\n");
483
484 do {
485 error = EINVAL;
486 printf("\nmountroot> ");
487 cngets(name, sizeof(name), GETS_ECHO);
488 if (name[0] == '\0')
489 break;
490 if (name[0] == '?' && name[1] == '\0') {
491 printf("\nList of GEOM managed disk devices:\n ");
492 g_dev_print();
493 continue;
494 }
495 if (name[0] == '.' && name[1] == '\0') {
496 pause("rmask", hz);
497 continue;
498 }
499 mnt = name;
500 error = parse_mount(&mnt);
501 if (error == -1)
502 printf("Invalid file system specification.\n");
503 } while (error != 0);
504
505 return (error);
506}
507
508static int
509parse_dir_md(char **conf)
510{
511 struct stat sb;
512 struct thread *td;
513 struct md_ioctl *mdio;
514 char *path, *tok;
515 int error, fd, len;
516
517 td = curthread;
518
519 error = parse_token(conf, &tok);
520 if (error)
521 return (error);
522
523 len = strlen(tok);
524 mdio = malloc(sizeof(*mdio) + len + 1, M_TEMP, M_WAITOK | M_ZERO);
525 path = (void *)(mdio + 1);
526 bcopy(tok, path, len);
527 free(tok, M_TEMP);
528
529 /* Get file status. */
530 error = kern_stat(td, path, UIO_SYSSPACE, &sb);
531 if (error)
532 goto out;
533
534 /* Open /dev/mdctl so that we can attach/detach. */
535 error = kern_open(td, "/dev/" MDCTL_NAME, UIO_SYSSPACE, O_RDWR, 0);
536 if (error)
537 goto out;
538
539 fd = td->td_retval[0];
540 mdio->md_version = MDIOVERSION;
541 mdio->md_type = MD_VNODE;
542
543 if (root_mount_mddev != -1) {
544 mdio->md_unit = root_mount_mddev;
545 DROP_GIANT();
546 error = kern_ioctl(td, fd, MDIOCDETACH, (void *)mdio);
547 PICKUP_GIANT();
548 /* Ignore errors. We don't care. */
549 root_mount_mddev = -1;
550 }
551
552 mdio->md_file = (void *)(mdio + 1);
553 mdio->md_options = MD_AUTOUNIT | MD_READONLY;
554 mdio->md_mediasize = sb.st_size;
555 mdio->md_unit = 0;
556 DROP_GIANT();
557 error = kern_ioctl(td, fd, MDIOCATTACH, (void *)mdio);
558 PICKUP_GIANT();
559 if (error)
560 goto out;
561
562 if (mdio->md_unit > 9) {
563 printf("rootmount: too many md units\n");
564 mdio->md_file = NULL;
565 mdio->md_options = 0;
566 mdio->md_mediasize = 0;
567 DROP_GIANT();
568 error = kern_ioctl(td, fd, MDIOCDETACH, (void *)mdio);
569 PICKUP_GIANT();
570 /* Ignore errors. We don't care. */
571 error = ERANGE;
572 goto out;
573 }
574
575 root_mount_mddev = mdio->md_unit;
576 printf(MD_NAME "%u attached to %s\n", root_mount_mddev, mdio->md_file);
577
578 error = kern_close(td, fd);
579
580 out:
581 free(mdio, M_TEMP);
582 return (error);
583}
584
585static int
586parse_dir_onfail(char **conf)
587{
588 char *action;
589 int error;
590
591 error = parse_token(conf, &action);
592 if (error)
593 return (error);
594
595 if (!strcmp(action, "continue"))
596 root_mount_onfail = A_CONTINUE;
597 else if (!strcmp(action, "panic"))
598 root_mount_onfail = A_PANIC;
599 else if (!strcmp(action, "reboot"))
600 root_mount_onfail = A_REBOOT;
601 else if (!strcmp(action, "retry"))
602 root_mount_onfail = A_RETRY;
603 else {
604 printf("rootmount: %s: unknown action\n", action);
605 error = EINVAL;
606 }
607
608 free(action, M_TEMP);
609 return (0);
610}
611
612static int
613parse_dir_timeout(char **conf)
614{
615 char *tok, *endtok;
616 long secs;
617 int error;
618
619 error = parse_token(conf, &tok);
620 if (error)
621 return (error);
622
623 secs = strtol(tok, &endtok, 0);
624 error = (secs < 0 || *endtok != '\0') ? EINVAL : 0;
625 if (!error)
626 root_mount_timeout = secs;
627 free(tok, M_TEMP);
628 return (error);
629}
630
631static int
632parse_directive(char **conf)
633{
634 char *dir;
635 int error;
636
637 error = parse_token(conf, &dir);
638 if (error)
639 return (error);
640
641 if (strcmp(dir, ".ask") == 0)
642 error = parse_dir_ask(conf);
643 else if (strcmp(dir, ".md") == 0)
644 error = parse_dir_md(conf);
645 else if (strcmp(dir, ".onfail") == 0)
646 error = parse_dir_onfail(conf);
647 else if (strcmp(dir, ".timeout") == 0)
648 error = parse_dir_timeout(conf);
649 else {
650 printf("mountroot: invalid directive `%s'\n", dir);
651 /* Ignore the rest of the line. */
652 (void)parse_skipto(conf, '\n');
653 error = EINVAL;
654 }
655 free(dir, M_TEMP);
656 return (error);
657}
658
659static int
660parse_mount_dev_present(const char *dev)
661{
662 struct nameidata nd;
663 int error;
664
665 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, dev, curthread);
666 error = namei(&nd);
667 if (!error)
668 vput(nd.ni_vp);
669 NDFREE(&nd, NDF_ONLY_PNBUF);
670 return (error != 0) ? 0 : 1;
671}
672
673#define ERRMSGL 255
674static int
675parse_mount(char **conf)
676{
677 char *errmsg;
678 struct mntarg *ma;
679 char *dev, *fs, *opts, *tok;
680 int delay, error, timeout;
681
682 error = parse_token(conf, &tok);
683 if (error)
684 return (error);
685 fs = tok;
686 error = parse_skipto(&tok, ':');
687 if (error) {
688 free(fs, M_TEMP);
689 return (error);
690 }
691 parse_poke(&tok, '\0');
692 parse_advance(&tok);
693 dev = tok;
694
695 if (root_mount_mddev != -1) {
696 /* Handle substitution for the md unit number. */
697 tok = strstr(dev, "md#");
698 if (tok != NULL)
699 tok[2] = '0' + root_mount_mddev;
700 }
701
702 /* Parse options. */
703 error = parse_token(conf, &tok);
704 opts = (error == 0) ? tok : NULL;
705
706 printf("Trying to mount root from %s:%s [%s]...\n", fs, dev,
707 (opts != NULL) ? opts : "");
708
709 errmsg = malloc(ERRMSGL, M_TEMP, M_WAITOK | M_ZERO);
710
711 if (vfs_byname(fs) == NULL) {
712 strlcpy(errmsg, "unknown file system", sizeof(errmsg));
713 error = ENOENT;
714 goto out;
715 }
716
717 if (strcmp(fs, "zfs") != 0 && strstr(fs, "nfs") == NULL &&
718 dev[0] != '\0' && !parse_mount_dev_present(dev)) {
719 printf("mountroot: waiting for device %s ...\n", dev);
720 delay = hz / 10;
721 timeout = root_mount_timeout * hz;
722 do {
723 pause("rmdev", delay);
724 timeout -= delay;
725 } while (timeout > 0 && !parse_mount_dev_present(dev));
726 if (timeout <= 0) {
727 error = ENODEV;
728 goto out;
729 }
730 }
731
732 ma = NULL;
733 ma = mount_arg(ma, "fstype", fs, -1);
734 ma = mount_arg(ma, "fspath", "/", -1);
735 ma = mount_arg(ma, "from", dev, -1);
736 ma = mount_arg(ma, "errmsg", errmsg, ERRMSGL);
737 ma = mount_arg(ma, "ro", NULL, 0);
738 ma = parse_mountroot_options(ma, opts);
739 error = kernel_mount(ma, MNT_ROOTFS);
740
741 out:
742 if (error) {
743 printf("Mounting from %s:%s failed with error %d",
744 fs, dev, error);
745 if (errmsg[0] != '\0')
746 printf(": %s", errmsg);
747 printf(".\n");
748 }
749 free(fs, M_TEMP);
750 free(errmsg, M_TEMP);
751 if (opts != NULL)
752 free(opts, M_TEMP);
753 /* kernel_mount can return -1 on error. */
754 return ((error < 0) ? EDOOFUS : error);
755}
756#undef ERRMSGL
757
758static int
759vfs_mountroot_parse(struct sbuf *sb, struct mount *mpdevfs)
760{
761 struct mount *mp;
762 char *conf;
763 int error;
764
765 root_mount_mddev = -1;
766
767retry:
768 conf = sbuf_data(sb);
769 mp = TAILQ_NEXT(mpdevfs, mnt_list);
770 error = (mp == NULL) ? 0 : EDOOFUS;
771 root_mount_onfail = A_CONTINUE;
772 while (mp == NULL) {
773 error = parse_skipto(&conf, CC_NONWHITESPACE);
774 if (error == PE_EOL) {
775 parse_advance(&conf);
776 continue;
777 }
778 if (error < 0)
779 break;
780 switch (parse_peek(&conf)) {
781 case '#':
782 error = parse_skipto(&conf, '\n');
783 break;
784 case '.':
785 error = parse_directive(&conf);
786 break;
787 default:
788 error = parse_mount(&conf);
789 break;
790 }
791 if (error < 0)
792 break;
793 /* Ignore any trailing garbage on the line. */
794 if (parse_peek(&conf) != '\n') {
795 printf("mountroot: advancing to next directive...\n");
796 (void)parse_skipto(&conf, '\n');
797 }
798 mp = TAILQ_NEXT(mpdevfs, mnt_list);
799 }
800 if (mp != NULL)
801 return (0);
802
803 /*
804 * We failed to mount (a new) root.
805 */
806 switch (root_mount_onfail) {
807 case A_CONTINUE:
808 break;
809 case A_PANIC:
810 panic("mountroot: unable to (re-)mount root.");
811 /* NOTREACHED */
812 case A_RETRY:
813 goto retry;
814 case A_REBOOT:
815 kern_reboot(RB_NOSYNC);
816 /* NOTREACHED */
817 }
818
819 return (error);
820}
821
822static void
823vfs_mountroot_conf0(struct sbuf *sb)
824{
825 char *s, *tok, *mnt, *opt;
826 int error;
827
828 sbuf_printf(sb, ".onfail panic\n");
829 sbuf_printf(sb, ".timeout %d\n", root_mount_timeout);
830 if (boothowto & RB_ASKNAME)
831 sbuf_printf(sb, ".ask\n");
832#ifdef ROOTDEVNAME
833 if (boothowto & RB_DFLTROOT)
834 sbuf_printf(sb, "%s\n", ROOTDEVNAME);
835#endif
836 if (boothowto & RB_CDROM) {
837 sbuf_printf(sb, "cd9660:/dev/cd0 ro\n");
838 sbuf_printf(sb, ".timeout 0\n");
839 sbuf_printf(sb, "cd9660:/dev/acd0 ro\n");
840 sbuf_printf(sb, ".timeout %d\n", root_mount_timeout);
841 }
842 s = getenv("vfs.root.mountfrom");
843 if (s != NULL) {
844 opt = getenv("vfs.root.mountfrom.options");
845 tok = s;
846 error = parse_token(&tok, &mnt);
847 while (!error) {
848 sbuf_printf(sb, "%s %s\n", mnt,
849 (opt != NULL) ? opt : "");
850 free(mnt, M_TEMP);
851 error = parse_token(&tok, &mnt);
852 }
853 if (opt != NULL)
854 freeenv(opt);
855 freeenv(s);
856 }
857 if (rootdevnames[0] != NULL)
858 sbuf_printf(sb, "%s\n", rootdevnames[0]);
859 if (rootdevnames[1] != NULL)
860 sbuf_printf(sb, "%s\n", rootdevnames[1]);
861#ifdef ROOTDEVNAME
862 if (!(boothowto & RB_DFLTROOT))
863 sbuf_printf(sb, "%s\n", ROOTDEVNAME);
864#endif
865 if (!(boothowto & RB_ASKNAME))
866 sbuf_printf(sb, ".ask\n");
867}
868
869static int
870vfs_mountroot_readconf(struct thread *td, struct sbuf *sb)
871{
872 static char buf[128];
873 struct nameidata nd;
874 off_t ofs;
875 ssize_t resid;
876 int error, flags, len;
877
878 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, "/.mount.conf", td);
879 flags = FREAD;
880 error = vn_open(&nd, &flags, 0, NULL);
881 if (error)
882 return (error);
883
884 NDFREE(&nd, NDF_ONLY_PNBUF);
885 ofs = 0;
886 len = sizeof(buf) - 1;
887 while (1) {
888 error = vn_rdwr(UIO_READ, nd.ni_vp, buf, len, ofs,
889 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred,
890 NOCRED, &resid, td);
891 if (error)
892 break;
893 if (resid == len)
894 break;
895 buf[len - resid] = 0;
896 sbuf_printf(sb, "%s", buf);
897 ofs += len - resid;
898 }
899
900 VOP_UNLOCK(nd.ni_vp, 0);
901 vn_close(nd.ni_vp, FREAD, td->td_ucred, td);
902 return (error);
903}
904
905static void
906vfs_mountroot_wait(void)
907{
908 struct root_hold_token *h;
909 struct timeval lastfail;
910 int curfail;
911
912 curfail = 0;
913 while (1) {
914 DROP_GIANT();
915 g_waitidle();
916 PICKUP_GIANT();
917 mtx_lock(&mountlist_mtx);
918 if (LIST_EMPTY(&root_holds)) {
919 mtx_unlock(&mountlist_mtx);
920 break;
921 }
922 if (ppsratecheck(&lastfail, &curfail, 1)) {
923 printf("Root mount waiting for:");
924 LIST_FOREACH(h, &root_holds, list)
925 printf(" %s", h->who);
926 printf("\n");
927 }
928 msleep(&root_holds, &mountlist_mtx, PZERO | PDROP, "roothold",
929 hz);
930 }
931}
932
933void
934vfs_mountroot(void)
935{
936 struct mount *mp;
937 struct sbuf *sb;
938 struct thread *td;
939 time_t timebase;
940 int error;
941
942 td = curthread;
943
944 vfs_mountroot_wait();
945
946 sb = sbuf_new_auto();
947 vfs_mountroot_conf0(sb);
948 sbuf_finish(sb);
949
950 error = vfs_mountroot_devfs(td, &mp);
951 while (!error) {
952 error = vfs_mountroot_parse(sb, mp);
953 if (!error) {
954 error = vfs_mountroot_shuffle(td, mp);
955 if (!error) {
956 sbuf_clear(sb);
957 error = vfs_mountroot_readconf(td, sb);
958 sbuf_finish(sb);
959 }
960 }
961 }
962
963 sbuf_delete(sb);
964
965 /*
966 * Iterate over all currently mounted file systems and use
967 * the time stamp found to check and/or initialize the RTC.
968 * Call inittodr() only once and pass it the largest of the
969 * timestamps we encounter.
970 */
971 timebase = 0;
972 mtx_lock(&mountlist_mtx);
973 mp = TAILQ_FIRST(&mountlist);
974 while (mp != NULL) {
975 if (mp->mnt_time > timebase)
976 timebase = mp->mnt_time;
977 mp = TAILQ_NEXT(mp, mnt_list);
978 }
979 mtx_unlock(&mountlist_mtx);
980 inittodr(timebase);
981
982 /* Keep prison0's root in sync with the global rootvnode. */
983 mtx_lock(&prison0.pr_mtx);
984 prison0.pr_root = rootvnode;
985 vref(prison0.pr_root);
986 mtx_unlock(&prison0.pr_mtx);
987
988 mtx_lock(&mountlist_mtx);
989 atomic_store_rel_int(&root_mount_complete, 1);
990 wakeup(&root_mount_complete);
991 mtx_unlock(&mountlist_mtx);
992
993 EVENTHANDLER_INVOKE(mountroot);
994}
995
996static struct mntarg *
997parse_mountroot_options(struct mntarg *ma, const char *options)
998{
999 char *p;
1000 char *name, *name_arg;
1001 char *val, *val_arg;
1002 char *opts;
1003
1004 if (options == NULL || options[0] == '\0')
1005 return (ma);
1006
1007 p = opts = strdup(options, M_MOUNT);
1008 if (opts == NULL) {
1009 return (ma);
1010 }
1011
1012 while((name = strsep(&p, ",")) != NULL) {
1013 if (name[0] == '\0')
1014 break;
1015
1016 val = strchr(name, '=');
1017 if (val != NULL) {
1018 *val = '\0';
1019 ++val;
1020 }
1021 if( strcmp(name, "rw") == 0 ||
1022 strcmp(name, "noro") == 0) {
1023 /*
1024 * The first time we mount the root file system,
1025 * we need to mount 'ro', so We need to ignore
1026 * 'rw' and 'noro' mount options.
1027 */
1028 continue;
1029 }
1030 name_arg = strdup(name, M_MOUNT);
1031 val_arg = NULL;
1032 if (val != NULL)
1033 val_arg = strdup(val, M_MOUNT);
1034
1035 ma = mount_arg(ma, name_arg, val_arg,
1036 (val_arg != NULL ? -1 : 0));
1037 }
1038 free(opts, M_MOUNT);
1039 return (ma);
1040}