1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 2010 Marcel Moolenaar
5 * Copyright (c) 1999-2004 Poul-Henning Kamp
6 * Copyright (c) 1999 Michael Smith
7 * Copyright (c) 1989, 1993
8 * The Regents of the University of California. All rights reserved.
9 * (c) UNIX System Laboratories, Inc.
10 * All or some portions of this file are derived from material licensed
11 * to the University of California by American Telephone and Telegraph
12 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
13 * the permission of UNIX System Laboratories, Inc.
14 *
15 * Redistribution and use in source and binary forms, with or without
16 * modification, are permitted provided that the following conditions
17 * are met:
18 * 1. Redistributions of source code must retain the above copyright
19 * notice, this list of conditions and the following disclaimer.
20 * 2. Redistributions in binary form must reproduce the above copyright
21 * notice, this list of conditions and the following disclaimer in the
22 * documentation and/or other materials provided with the distribution.
23 * 3. Neither the name of the University nor the names of its contributors
24 * may be used to endorse or promote products derived from this software
25 * without specific prior written permission.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37 * SUCH DAMAGE.
38 */
39
40 #include "opt_rootdevname.h"
41
42 #include <sys/cdefs.h>
43 __FBSDID("$FreeBSD$");
44
45 #include <sys/param.h>
46 #include <sys/conf.h>
47 #include <sys/cons.h>
48 #include <sys/eventhandler.h>
49 #include <sys/fcntl.h>
50 #include <sys/jail.h>
51 #include <sys/kernel.h>
52 #include <sys/malloc.h>
53 #include <sys/mdioctl.h>
54 #include <sys/mount.h>
55 #include <sys/mutex.h>
56 #include <sys/namei.h>
57 #include <sys/priv.h>
58 #include <sys/proc.h>
59 #include <sys/filedesc.h>
60 #include <sys/reboot.h>
61 #include <sys/sbuf.h>
62 #include <sys/stat.h>
63 #include <sys/syscallsubr.h>
64 #include <sys/sysproto.h>
65 #include <sys/sx.h>
66 #include <sys/sysctl.h>
67 #include <sys/systm.h>
68 #include <sys/vnode.h>
69
70 #include <geom/geom.h>
71
72 /*
73 * The root filesystem is detailed in the kernel environment variable
74 * vfs.root.mountfrom, which is expected to be in the general format
75 *
76 * <vfsname>:[<path>][ <vfsname>:[<path>] ...]
77 * vfsname := the name of a VFS known to the kernel and capable
78 * of being mounted as root
79 * path := disk device name or other data used by the filesystem
80 * to locate its physical store
81 *
82 * If the environment variable vfs.root.mountfrom is a space separated list,
83 * each list element is tried in turn and the root filesystem will be mounted
84 * from the first one that succeeds.
85 *
86 * The environment variable vfs.root.mountfrom.options is a comma delimited
87 * set of string mount options. These mount options must be parseable
88 * by nmount() in the kernel.
89 */
90
91 static int parse_mount(char **);
92 static struct mntarg *parse_mountroot_options(struct mntarg *, const char *);
93 static int sysctl_vfs_root_mount_hold(SYSCTL_HANDLER_ARGS);
94 static void vfs_mountroot_wait(void);
95 static int vfs_mountroot_wait_if_neccessary(const char *fs, const char *dev);
96
97 /*
98 * The vnode of the system's root (/ in the filesystem, without chroot
99 * active.)
100 */
101 struct vnode *rootvnode;
102
103 /*
104 * Mount of the system's /dev.
105 */
106 struct mount *rootdevmp;
107
108 char *rootdevnames[2] = {NULL, NULL};
109
110 struct mtx root_holds_mtx;
111 MTX_SYSINIT(root_holds, &root_holds_mtx, "root_holds", MTX_DEF);
112
113 static TAILQ_HEAD(, root_hold_token) root_holds =
114 TAILQ_HEAD_INITIALIZER(root_holds);
115
116 enum action {
117 A_CONTINUE,
118 A_PANIC,
119 A_REBOOT,
120 A_RETRY
121 };
122
123 enum rh_flags {
124 RH_FREE,
125 RH_ALLOC,
126 RH_ARG,
127 };
128
129 static enum action root_mount_onfail = A_CONTINUE;
130
131 static int root_mount_mddev;
132 static int root_mount_complete;
133
134 /* By default wait up to 3 seconds for devices to appear. */
135 static int root_mount_timeout = 3;
136 TUNABLE_INT("vfs.mountroot.timeout", &root_mount_timeout);
137
138 static int root_mount_always_wait = 0;
139 SYSCTL_INT(_vfs, OID_AUTO, root_mount_always_wait, CTLFLAG_RDTUN,
140 &root_mount_always_wait, 0,
141 "Wait for root mount holds even if the root device already exists");
142
143 SYSCTL_PROC(_vfs, OID_AUTO, root_mount_hold,
144 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE,
145 NULL, 0, sysctl_vfs_root_mount_hold, "A",
146 "List of root mount hold tokens");
147
148 static int
149 sysctl_vfs_root_mount_hold(SYSCTL_HANDLER_ARGS)
150 {
151 struct sbuf sb;
152 struct root_hold_token *h;
153 int error;
154
155 sbuf_new(&sb, NULL, 256, SBUF_AUTOEXTEND | SBUF_INCLUDENUL);
156
157 mtx_lock(&root_holds_mtx);
158 TAILQ_FOREACH(h, &root_holds, list) {
159 if (h != TAILQ_FIRST(&root_holds))
160 sbuf_putc(&sb, ' ');
161 sbuf_printf(&sb, "%s", h->who);
162 }
163 mtx_unlock(&root_holds_mtx);
164
165 error = sbuf_finish(&sb);
166 if (error == 0)
167 error = SYSCTL_OUT(req, sbuf_data(&sb), sbuf_len(&sb));
168 sbuf_delete(&sb);
169 return (error);
170 }
171
172 struct root_hold_token *
173 root_mount_hold(const char *identifier)
174 {
175 struct root_hold_token *h;
176
177 h = malloc(sizeof *h, M_DEVBUF, M_ZERO | M_WAITOK);
178 h->flags = RH_ALLOC;
179 h->who = identifier;
180 mtx_lock(&root_holds_mtx);
181 TSHOLD("root mount");
182 TAILQ_INSERT_TAIL(&root_holds, h, list);
183 mtx_unlock(&root_holds_mtx);
184 return (h);
185 }
186
187 void
188 root_mount_hold_token(const char *identifier, struct root_hold_token *h)
189 {
190 #ifdef INVARIANTS
191 struct root_hold_token *t;
192 #endif
193
194 h->flags = RH_ARG;
195 h->who = identifier;
196 mtx_lock(&root_holds_mtx);
197 #ifdef INVARIANTS
198 TAILQ_FOREACH(t, &root_holds, list) {
199 if (t == h) {
200 panic("Duplicate mount hold by '%s' on %p",
201 identifier, h);
202 }
203 }
204 #endif
205 TSHOLD("root mount");
206 TAILQ_INSERT_TAIL(&root_holds, h, list);
207 mtx_unlock(&root_holds_mtx);
208 }
209
210 void
211 root_mount_rel(struct root_hold_token *h)
212 {
213
214 if (h == NULL || h->flags == RH_FREE)
215 return;
216
217 mtx_lock(&root_holds_mtx);
218 TAILQ_REMOVE(&root_holds, h, list);
219 TSRELEASE("root mount");
220 wakeup(&root_holds);
221 mtx_unlock(&root_holds_mtx);
222 if (h->flags == RH_ALLOC) {
223 free(h, M_DEVBUF);
224 } else
225 h->flags = RH_FREE;
226 }
227
228 int
229 root_mounted(void)
230 {
231
232 /* No mutex is acquired here because int stores are atomic. */
233 return (root_mount_complete);
234 }
235
236 static void
237 set_rootvnode(void)
238 {
239
240 if (VFS_ROOT(TAILQ_FIRST(&mountlist), LK_EXCLUSIVE, &rootvnode))
241 panic("set_rootvnode: Cannot find root vnode");
242
243 VOP_UNLOCK(rootvnode);
244
245 pwd_set_rootvnode();
246 }
247
248 static int
249 vfs_mountroot_devfs(struct thread *td, struct mount **mpp)
250 {
251 struct vfsoptlist *opts;
252 struct vfsconf *vfsp;
253 struct mount *mp;
254 int error;
255
256 *mpp = NULL;
257
258 if (rootdevmp != NULL) {
259 /*
260 * Already have /dev; this happens during rerooting.
261 */
262 error = vfs_busy(rootdevmp, 0);
263 if (error != 0)
264 return (error);
265 *mpp = rootdevmp;
266 } else {
267 vfsp = vfs_byname("devfs");
268 KASSERT(vfsp != NULL, ("Could not find devfs by name"));
269 if (vfsp == NULL)
270 return (ENOENT);
271
272 mp = vfs_mount_alloc(NULLVP, vfsp, "/dev", td->td_ucred);
273
274 error = VFS_MOUNT(mp);
275 KASSERT(error == 0, ("VFS_MOUNT(devfs) failed %d", error));
276 if (error)
277 return (error);
278
279 error = VFS_STATFS(mp, &mp->mnt_stat);
280 KASSERT(error == 0, ("VFS_STATFS(devfs) failed %d", error));
281 if (error)
282 return (error);
283
284 opts = malloc(sizeof(struct vfsoptlist), M_MOUNT, M_WAITOK);
285 TAILQ_INIT(opts);
286 mp->mnt_opt = opts;
287
288 mtx_lock(&mountlist_mtx);
289 TAILQ_INSERT_HEAD(&mountlist, mp, mnt_list);
290 mtx_unlock(&mountlist_mtx);
291
292 *mpp = mp;
293 rootdevmp = mp;
294 vfs_op_exit(mp);
295 }
296
297 set_rootvnode();
298
299 error = kern_symlinkat(td, "/", AT_FDCWD, "dev", UIO_SYSSPACE);
300 if (error)
301 printf("kern_symlink /dev -> / returns %d\n", error);
302
303 return (error);
304 }
305
306 static void
307 vfs_mountroot_shuffle(struct thread *td, struct mount *mpdevfs)
308 {
309 struct nameidata nd;
310 struct mount *mporoot, *mpnroot;
311 struct vnode *vp, *vporoot, *vpdevfs;
312 char *fspath;
313 int error;
314
315 mpnroot = TAILQ_NEXT(mpdevfs, mnt_list);
316
317 /* Shuffle the mountlist. */
318 mtx_lock(&mountlist_mtx);
319 mporoot = TAILQ_FIRST(&mountlist);
320 TAILQ_REMOVE(&mountlist, mpdevfs, mnt_list);
321 if (mporoot != mpdevfs) {
322 TAILQ_REMOVE(&mountlist, mpnroot, mnt_list);
323 TAILQ_INSERT_HEAD(&mountlist, mpnroot, mnt_list);
324 }
325 TAILQ_INSERT_TAIL(&mountlist, mpdevfs, mnt_list);
326 mtx_unlock(&mountlist_mtx);
327
328 cache_purgevfs(mporoot);
329 if (mporoot != mpdevfs)
330 cache_purgevfs(mpdevfs);
331
332 if (VFS_ROOT(mporoot, LK_EXCLUSIVE, &vporoot))
333 panic("vfs_mountroot_shuffle: Cannot find root vnode");
334
335 VI_LOCK(vporoot);
336 vporoot->v_iflag &= ~VI_MOUNT;
337 vn_irflag_unset_locked(vporoot, VIRF_MOUNTPOINT);
338 vporoot->v_mountedhere = NULL;
339 VI_UNLOCK(vporoot);
340 mporoot->mnt_flag &= ~MNT_ROOTFS;
341 mporoot->mnt_vnodecovered = NULL;
342 vput(vporoot);
343
344 /* Set up the new rootvnode, and purge the cache */
345 mpnroot->mnt_vnodecovered = NULL;
346 set_rootvnode();
347 cache_purgevfs(rootvnode->v_mount);
348
349 if (mporoot != mpdevfs) {
350 /* Remount old root under /.mount or /mnt */
351 fspath = "/.mount";
352 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE,
353 fspath, td);
354 error = namei(&nd);
355 if (error) {
356 NDFREE(&nd, NDF_ONLY_PNBUF);
357 fspath = "/mnt";
358 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE,
359 fspath, td);
360 error = namei(&nd);
361 }
362 if (!error) {
363 vp = nd.ni_vp;
364 error = (vp->v_type == VDIR) ? 0 : ENOTDIR;
365 if (!error)
366 error = vinvalbuf(vp, V_SAVE, 0, 0);
367 if (!error) {
368 cache_purge(vp);
369 VI_LOCK(vp);
370 mporoot->mnt_vnodecovered = vp;
371 vn_irflag_set_locked(vp, VIRF_MOUNTPOINT);
372 vp->v_mountedhere = mporoot;
373 strlcpy(mporoot->mnt_stat.f_mntonname,
374 fspath, MNAMELEN);
375 VI_UNLOCK(vp);
376 VOP_UNLOCK(vp);
377 } else
378 vput(vp);
379 }
380 NDFREE(&nd, NDF_ONLY_PNBUF);
381
382 if (error)
383 printf("mountroot: unable to remount previous root "
384 "under /.mount or /mnt (error %d)\n", error);
385 }
386
387 /* Remount devfs under /dev */
388 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, "/dev", td);
389 error = namei(&nd);
390 if (!error) {
391 vp = nd.ni_vp;
392 error = (vp->v_type == VDIR) ? 0 : ENOTDIR;
393 if (!error)
394 error = vinvalbuf(vp, V_SAVE, 0, 0);
395 if (!error) {
396 vpdevfs = mpdevfs->mnt_vnodecovered;
397 if (vpdevfs != NULL) {
398 cache_purge(vpdevfs);
399 VI_LOCK(vpdevfs);
400 vn_irflag_unset_locked(vpdevfs, VIRF_MOUNTPOINT);
401 vpdevfs->v_mountedhere = NULL;
402 VI_UNLOCK(vpdevfs);
403 vrele(vpdevfs);
404 }
405 VI_LOCK(vp);
406 mpdevfs->mnt_vnodecovered = vp;
407 vn_irflag_set_locked(vp, VIRF_MOUNTPOINT);
408 vp->v_mountedhere = mpdevfs;
409 VI_UNLOCK(vp);
410 VOP_UNLOCK(vp);
411 } else
412 vput(vp);
413 }
414 if (error)
415 printf("mountroot: unable to remount devfs under /dev "
416 "(error %d)\n", error);
417 NDFREE(&nd, NDF_ONLY_PNBUF);
418
419 if (mporoot == mpdevfs) {
420 vfs_unbusy(mpdevfs);
421 /* Unlink the no longer needed /dev/dev -> / symlink */
422 error = kern_funlinkat(td, AT_FDCWD, "/dev/dev", FD_NONE,
423 UIO_SYSSPACE, 0, 0);
424 if (error)
425 printf("mountroot: unable to unlink /dev/dev "
426 "(error %d)\n", error);
427 }
428 }
429
430 /*
431 * Configuration parser.
432 */
433
434 /* Parser character classes. */
435 #define CC_WHITESPACE -1
436 #define CC_NONWHITESPACE -2
437
438 /* Parse errors. */
439 #define PE_EOF -1
440 #define PE_EOL -2
441
442 static __inline int
443 parse_peek(char **conf)
444 {
445
446 return (**conf);
447 }
448
449 static __inline void
450 parse_poke(char **conf, int c)
451 {
452
453 **conf = c;
454 }
455
456 static __inline void
457 parse_advance(char **conf)
458 {
459
460 (*conf)++;
461 }
462
463 static int
464 parse_skipto(char **conf, int mc)
465 {
466 int c, match;
467
468 while (1) {
469 c = parse_peek(conf);
470 if (c == 0)
471 return (PE_EOF);
472 switch (mc) {
473 case CC_WHITESPACE:
474 match = (c == ' ' || c == '\t' || c == '\n') ? 1 : 0;
475 break;
476 case CC_NONWHITESPACE:
477 if (c == '\n')
478 return (PE_EOL);
479 match = (c != ' ' && c != '\t') ? 1 : 0;
480 break;
481 default:
482 match = (c == mc) ? 1 : 0;
483 break;
484 }
485 if (match)
486 break;
487 parse_advance(conf);
488 }
489 return (0);
490 }
491
492 static int
493 parse_token(char **conf, char **tok)
494 {
495 char *p;
496 size_t len;
497 int error;
498
499 *tok = NULL;
500 error = parse_skipto(conf, CC_NONWHITESPACE);
501 if (error)
502 return (error);
503 p = *conf;
504 error = parse_skipto(conf, CC_WHITESPACE);
505 len = *conf - p;
506 *tok = malloc(len + 1, M_TEMP, M_WAITOK | M_ZERO);
507 bcopy(p, *tok, len);
508 return (0);
509 }
510
511 static void
512 parse_dir_ask_printenv(const char *var)
513 {
514 char *val;
515
516 val = kern_getenv(var);
517 if (val != NULL) {
518 printf(" %s=%s\n", var, val);
519 freeenv(val);
520 }
521 }
522
523 static int
524 parse_dir_ask(char **conf)
525 {
526 char name[80];
527 char *mnt;
528 int error;
529
530 vfs_mountroot_wait();
531
532 printf("\nLoader variables:\n");
533 parse_dir_ask_printenv("vfs.root.mountfrom");
534 parse_dir_ask_printenv("vfs.root.mountfrom.options");
535
536 printf("\nManual root filesystem specification:\n");
537 printf(" <fstype>:<device> [options]\n");
538 printf(" Mount <device> using filesystem <fstype>\n");
539 printf(" and with the specified (optional) option list.\n");
540 printf("\n");
541 printf(" eg. ufs:/dev/da0s1a\n");
542 printf(" zfs:zroot/ROOT/default\n");
543 printf(" cd9660:/dev/cd0 ro\n");
544 printf(" (which is equivalent to: ");
545 printf("mount -t cd9660 -o ro /dev/cd0 /)\n");
546 printf("\n");
547 printf(" ? List valid disk boot devices\n");
548 printf(" . Yield 1 second (for background tasks)\n");
549 printf(" <empty line> Abort manual input\n");
550
551 do {
552 error = EINVAL;
553 printf("\nmountroot> ");
554 cngets(name, sizeof(name), GETS_ECHO);
555 if (name[0] == '\0')
556 break;
557 if (name[0] == '?' && name[1] == '\0') {
558 printf("\nList of GEOM managed disk devices:\n ");
559 g_dev_print();
560 continue;
561 }
562 if (name[0] == '.' && name[1] == '\0') {
563 pause("rmask", hz);
564 continue;
565 }
566 mnt = name;
567 error = parse_mount(&mnt);
568 if (error == -1)
569 printf("Invalid file system specification.\n");
570 } while (error != 0);
571
572 return (error);
573 }
574
575 static int
576 parse_dir_md(char **conf)
577 {
578 struct stat sb;
579 struct thread *td;
580 struct md_ioctl *mdio;
581 char *path, *tok;
582 int error, fd, len;
583
584 td = curthread;
585 fd = -1;
586
587 error = parse_token(conf, &tok);
588 if (error)
589 return (error);
590
591 len = strlen(tok);
592 mdio = malloc(sizeof(*mdio) + len + 1, M_TEMP, M_WAITOK | M_ZERO);
593 path = (void *)(mdio + 1);
594 bcopy(tok, path, len);
595 free(tok, M_TEMP);
596
597 /* Get file status. */
598 error = kern_statat(td, 0, AT_FDCWD, path, UIO_SYSSPACE, &sb, NULL);
599 if (error)
600 goto out;
601
602 /* Open /dev/mdctl so that we can attach/detach. */
603 error = kern_openat(td, AT_FDCWD, "/dev/" MDCTL_NAME, UIO_SYSSPACE,
604 O_RDWR, 0);
605 if (error)
606 goto out;
607
608 fd = td->td_retval[0];
609 mdio->md_version = MDIOVERSION;
610 mdio->md_type = MD_VNODE;
611
612 if (root_mount_mddev != -1) {
613 mdio->md_unit = root_mount_mddev;
614 (void)kern_ioctl(td, fd, MDIOCDETACH, (void *)mdio);
615 /* Ignore errors. We don't care. */
616 root_mount_mddev = -1;
617 }
618
619 mdio->md_file = (void *)(mdio + 1);
620 mdio->md_options = MD_AUTOUNIT | MD_READONLY;
621 mdio->md_mediasize = sb.st_size;
622 mdio->md_unit = 0;
623 error = kern_ioctl(td, fd, MDIOCATTACH, (void *)mdio);
624 if (error)
625 goto out;
626
627 if (mdio->md_unit > 9) {
628 printf("rootmount: too many md units\n");
629 mdio->md_file = NULL;
630 mdio->md_options = 0;
631 mdio->md_mediasize = 0;
632 error = kern_ioctl(td, fd, MDIOCDETACH, (void *)mdio);
633 /* Ignore errors. We don't care. */
634 error = ERANGE;
635 goto out;
636 }
637
638 root_mount_mddev = mdio->md_unit;
639 printf(MD_NAME "%u attached to %s\n", root_mount_mddev, mdio->md_file);
640
641 out:
642 if (fd >= 0)
643 (void)kern_close(td, fd);
644 free(mdio, M_TEMP);
645 return (error);
646 }
647
648 static int
649 parse_dir_onfail(char **conf)
650 {
651 char *action;
652 int error;
653
654 error = parse_token(conf, &action);
655 if (error)
656 return (error);
657
658 if (!strcmp(action, "continue"))
659 root_mount_onfail = A_CONTINUE;
660 else if (!strcmp(action, "panic"))
661 root_mount_onfail = A_PANIC;
662 else if (!strcmp(action, "reboot"))
663 root_mount_onfail = A_REBOOT;
664 else if (!strcmp(action, "retry"))
665 root_mount_onfail = A_RETRY;
666 else {
667 printf("rootmount: %s: unknown action\n", action);
668 error = EINVAL;
669 }
670
671 free(action, M_TEMP);
672 return (0);
673 }
674
675 static int
676 parse_dir_timeout(char **conf)
677 {
678 char *tok, *endtok;
679 long secs;
680 int error;
681
682 error = parse_token(conf, &tok);
683 if (error)
684 return (error);
685
686 secs = strtol(tok, &endtok, 0);
687 error = (secs < 0 || *endtok != '\0') ? EINVAL : 0;
688 if (!error)
689 root_mount_timeout = secs;
690 free(tok, M_TEMP);
691 return (error);
692 }
693
694 static int
695 parse_directive(char **conf)
696 {
697 char *dir;
698 int error;
699
700 error = parse_token(conf, &dir);
701 if (error)
702 return (error);
703
704 if (strcmp(dir, ".ask") == 0)
705 error = parse_dir_ask(conf);
706 else if (strcmp(dir, ".md") == 0)
707 error = parse_dir_md(conf);
708 else if (strcmp(dir, ".onfail") == 0)
709 error = parse_dir_onfail(conf);
710 else if (strcmp(dir, ".timeout") == 0)
711 error = parse_dir_timeout(conf);
712 else {
713 printf("mountroot: invalid directive `%s'\n", dir);
714 /* Ignore the rest of the line. */
715 (void)parse_skipto(conf, '\n');
716 error = EINVAL;
717 }
718 free(dir, M_TEMP);
719 return (error);
720 }
721
722 static int
723 parse_mount_dev_present(const char *dev)
724 {
725 struct nameidata nd;
726 int error;
727
728 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, dev, curthread);
729 error = namei(&nd);
730 if (!error)
731 vput(nd.ni_vp);
732 NDFREE(&nd, NDF_ONLY_PNBUF);
733 return (error != 0) ? 0 : 1;
734 }
735
736 #define ERRMSGL 255
737 static int
738 parse_mount(char **conf)
739 {
740 char *errmsg;
741 struct mntarg *ma;
742 char *dev, *fs, *opts, *tok;
743 int delay, error, timeout;
744
745 error = parse_token(conf, &tok);
746 if (error)
747 return (error);
748 fs = tok;
749 error = parse_skipto(&tok, ':');
750 if (error) {
751 free(fs, M_TEMP);
752 return (error);
753 }
754 parse_poke(&tok, '\0');
755 parse_advance(&tok);
756 dev = tok;
757
758 if (root_mount_mddev != -1) {
759 /* Handle substitution for the md unit number. */
760 tok = strstr(dev, "md#");
761 if (tok != NULL)
762 tok[2] = '' + root_mount_mddev;
763 }
764
765 /* Parse options. */
766 error = parse_token(conf, &tok);
767 opts = (error == 0) ? tok : NULL;
768
769 printf("Trying to mount root from %s:%s [%s]...\n", fs, dev,
770 (opts != NULL) ? opts : "");
771
772 errmsg = malloc(ERRMSGL, M_TEMP, M_WAITOK | M_ZERO);
773
774 if (vfs_byname(fs) == NULL) {
775 strlcpy(errmsg, "unknown file system", ERRMSGL);
776 error = ENOENT;
777 goto out;
778 }
779
780 error = vfs_mountroot_wait_if_neccessary(fs, dev);
781 if (error != 0)
782 goto out;
783
784 delay = hz / 10;
785 timeout = root_mount_timeout * hz;
786
787 for (;;) {
788 ma = NULL;
789 ma = mount_arg(ma, "fstype", fs, -1);
790 ma = mount_arg(ma, "fspath", "/", -1);
791 ma = mount_arg(ma, "from", dev, -1);
792 ma = mount_arg(ma, "errmsg", errmsg, ERRMSGL);
793 ma = mount_arg(ma, "ro", NULL, 0);
794 ma = parse_mountroot_options(ma, opts);
795
796 error = kernel_mount(ma, MNT_ROOTFS);
797 if (error == 0 || timeout <= 0)
798 break;
799
800 if (root_mount_timeout * hz == timeout ||
801 (bootverbose && timeout % hz == 0)) {
802 printf("Mounting from %s:%s failed with error %d; "
803 "retrying for %d more second%s\n", fs, dev, error,
804 timeout / hz, (timeout / hz > 1) ? "s" : "");
805 }
806 pause("rmretry", delay);
807 timeout -= delay;
808 }
809 out:
810 if (error) {
811 printf("Mounting from %s:%s failed with error %d",
812 fs, dev, error);
813 if (errmsg[0] != '\0')
814 printf(": %s", errmsg);
815 printf(".\n");
816 }
817 free(fs, M_TEMP);
818 free(errmsg, M_TEMP);
819 if (opts != NULL)
820 free(opts, M_TEMP);
821 /* kernel_mount can return -1 on error. */
822 return ((error < 0) ? EDOOFUS : error);
823 }
824 #undef ERRMSGL
825
826 static int
827 vfs_mountroot_parse(struct sbuf *sb, struct mount *mpdevfs)
828 {
829 struct mount *mp;
830 char *conf;
831 int error;
832
833 root_mount_mddev = -1;
834
835 retry:
836 conf = sbuf_data(sb);
837 mp = TAILQ_NEXT(mpdevfs, mnt_list);
838 error = (mp == NULL) ? 0 : EDOOFUS;
839 root_mount_onfail = A_CONTINUE;
840 while (mp == NULL) {
841 error = parse_skipto(&conf, CC_NONWHITESPACE);
842 if (error == PE_EOL) {
843 parse_advance(&conf);
844 continue;
845 }
846 if (error < 0)
847 break;
848 switch (parse_peek(&conf)) {
849 case '#':
850 error = parse_skipto(&conf, '\n');
851 break;
852 case '.':
853 error = parse_directive(&conf);
854 break;
855 default:
856 error = parse_mount(&conf);
857 if (error == -1) {
858 printf("mountroot: invalid file system "
859 "specification.\n");
860 error = 0;
861 }
862 break;
863 }
864 if (error < 0)
865 break;
866 /* Ignore any trailing garbage on the line. */
867 if (parse_peek(&conf) != '\n') {
868 printf("mountroot: advancing to next directive...\n");
869 (void)parse_skipto(&conf, '\n');
870 }
871 mp = TAILQ_NEXT(mpdevfs, mnt_list);
872 }
873 if (mp != NULL)
874 return (0);
875
876 /*
877 * We failed to mount (a new) root.
878 */
879 switch (root_mount_onfail) {
880 case A_CONTINUE:
881 break;
882 case A_PANIC:
883 panic("mountroot: unable to (re-)mount root.");
884 /* NOTREACHED */
885 case A_RETRY:
886 goto retry;
887 case A_REBOOT:
888 kern_reboot(RB_NOSYNC);
889 /* NOTREACHED */
890 }
891
892 return (error);
893 }
894
895 static void
896 vfs_mountroot_conf0(struct sbuf *sb)
897 {
898 char *s, *tok, *mnt, *opt;
899 int error;
900
901 sbuf_printf(sb, ".onfail panic\n");
902 sbuf_printf(sb, ".timeout %d\n", root_mount_timeout);
903 if (boothowto & RB_ASKNAME)
904 sbuf_printf(sb, ".ask\n");
905 #ifdef ROOTDEVNAME
906 if (boothowto & RB_DFLTROOT)
907 sbuf_printf(sb, "%s\n", ROOTDEVNAME);
908 #endif
909 if (boothowto & RB_CDROM) {
910 sbuf_printf(sb, "cd9660:/dev/cd0 ro\n");
911 sbuf_printf(sb, ".timeout 0\n");
912 sbuf_printf(sb, "cd9660:/dev/cd1 ro\n");
913 sbuf_printf(sb, ".timeout %d\n", root_mount_timeout);
914 }
915 s = kern_getenv("vfs.root.mountfrom");
916 if (s != NULL) {
917 opt = kern_getenv("vfs.root.mountfrom.options");
918 tok = s;
919 error = parse_token(&tok, &mnt);
920 while (!error) {
921 sbuf_printf(sb, "%s %s\n", mnt,
922 (opt != NULL) ? opt : "");
923 free(mnt, M_TEMP);
924 error = parse_token(&tok, &mnt);
925 }
926 if (opt != NULL)
927 freeenv(opt);
928 freeenv(s);
929 }
930 if (rootdevnames[0] != NULL)
931 sbuf_printf(sb, "%s\n", rootdevnames[0]);
932 if (rootdevnames[1] != NULL)
933 sbuf_printf(sb, "%s\n", rootdevnames[1]);
934 #ifdef ROOTDEVNAME
935 if (!(boothowto & RB_DFLTROOT))
936 sbuf_printf(sb, "%s\n", ROOTDEVNAME);
937 #endif
938 if (!(boothowto & RB_ASKNAME))
939 sbuf_printf(sb, ".ask\n");
940 }
941
942 static int
943 vfs_mountroot_readconf(struct thread *td, struct sbuf *sb)
944 {
945 static char buf[128];
946 struct nameidata nd;
947 off_t ofs;
948 ssize_t resid;
949 int error, flags, len;
950
951 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, "/.mount.conf", td);
952 flags = FREAD;
953 error = vn_open(&nd, &flags, 0, NULL);
954 if (error)
955 return (error);
956
957 NDFREE(&nd, NDF_ONLY_PNBUF);
958 ofs = 0;
959 len = sizeof(buf) - 1;
960 while (1) {
961 error = vn_rdwr(UIO_READ, nd.ni_vp, buf, len, ofs,
962 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred,
963 NOCRED, &resid, td);
964 if (error)
965 break;
966 if (resid == len)
967 break;
968 buf[len - resid] = 0;
969 sbuf_printf(sb, "%s", buf);
970 ofs += len - resid;
971 }
972
973 VOP_UNLOCK(nd.ni_vp);
974 vn_close(nd.ni_vp, FREAD, td->td_ucred, td);
975 return (error);
976 }
977
978 static void
979 vfs_mountroot_wait(void)
980 {
981 struct root_hold_token *h;
982 struct timeval lastfail;
983 int curfail;
984
985 TSENTER();
986
987 curfail = 0;
988 lastfail.tv_sec = 0;
989 ppsratecheck(&lastfail, &curfail, 1);
990 while (1) {
991 g_waitidle();
992 mtx_lock(&root_holds_mtx);
993 if (TAILQ_EMPTY(&root_holds)) {
994 mtx_unlock(&root_holds_mtx);
995 break;
996 }
997 if (ppsratecheck(&lastfail, &curfail, 1)) {
998 printf("Root mount waiting for:");
999 TAILQ_FOREACH(h, &root_holds, list)
1000 printf(" %s", h->who);
1001 printf("\n");
1002 }
1003 TSWAIT("root mount");
1004 msleep(&root_holds, &root_holds_mtx, PZERO | PDROP, "roothold",
1005 hz);
1006 TSUNWAIT("root mount");
1007 }
1008 g_waitidle();
1009
1010 TSEXIT();
1011 }
1012
1013 static int
1014 vfs_mountroot_wait_if_neccessary(const char *fs, const char *dev)
1015 {
1016 int delay, timeout;
1017
1018 /*
1019 * In case of ZFS and NFS we don't have a way to wait for
1020 * specific device. Also do the wait if the user forced that
1021 * behaviour by setting vfs.root_mount_always_wait=1.
1022 */
1023 if (strcmp(fs, "zfs") == 0 || strstr(fs, "nfs") != NULL ||
1024 dev[0] == '\0' || root_mount_always_wait != 0) {
1025 vfs_mountroot_wait();
1026 return (0);
1027 }
1028
1029 /*
1030 * Otherwise, no point in waiting if the device is already there.
1031 * Note that we must wait for GEOM to finish reconfiguring itself,
1032 * eg for geom_part(4) to finish tasting.
1033 */
1034 g_waitidle();
1035 if (parse_mount_dev_present(dev))
1036 return (0);
1037
1038 /*
1039 * No luck. Let's wait. This code looks weird, but it's that way
1040 * to behave exactly as it used to work before.
1041 */
1042 vfs_mountroot_wait();
1043 if (parse_mount_dev_present(dev))
1044 return (0);
1045 printf("mountroot: waiting for device %s...\n", dev);
1046 delay = hz / 10;
1047 timeout = root_mount_timeout * hz;
1048 do {
1049 pause("rmdev", delay);
1050 timeout -= delay;
1051 } while (timeout > 0 && !parse_mount_dev_present(dev));
1052
1053 if (timeout <= 0)
1054 return (ENODEV);
1055
1056 return (0);
1057 }
1058
1059 void
1060 vfs_mountroot(void)
1061 {
1062 struct mount *mp;
1063 struct sbuf *sb;
1064 struct thread *td;
1065 time_t timebase;
1066 int error;
1067
1068 mtx_assert(&Giant, MA_NOTOWNED);
1069
1070 TSENTER();
1071
1072 td = curthread;
1073
1074 sb = sbuf_new_auto();
1075 vfs_mountroot_conf0(sb);
1076 sbuf_finish(sb);
1077
1078 error = vfs_mountroot_devfs(td, &mp);
1079 while (!error) {
1080 error = vfs_mountroot_parse(sb, mp);
1081 if (!error) {
1082 vfs_mountroot_shuffle(td, mp);
1083 sbuf_clear(sb);
1084 error = vfs_mountroot_readconf(td, sb);
1085 sbuf_finish(sb);
1086 }
1087 }
1088
1089 sbuf_delete(sb);
1090
1091 /*
1092 * Iterate over all currently mounted file systems and use
1093 * the time stamp found to check and/or initialize the RTC.
1094 * Call inittodr() only once and pass it the largest of the
1095 * timestamps we encounter.
1096 */
1097 timebase = 0;
1098 mtx_lock(&mountlist_mtx);
1099 mp = TAILQ_FIRST(&mountlist);
1100 while (mp != NULL) {
1101 if (mp->mnt_time > timebase)
1102 timebase = mp->mnt_time;
1103 mp = TAILQ_NEXT(mp, mnt_list);
1104 }
1105 mtx_unlock(&mountlist_mtx);
1106 inittodr(timebase);
1107
1108 /* Keep prison0's root in sync with the global rootvnode. */
1109 mtx_lock(&prison0.pr_mtx);
1110 prison0.pr_root = rootvnode;
1111 vref(prison0.pr_root);
1112 mtx_unlock(&prison0.pr_mtx);
1113
1114 mtx_lock(&root_holds_mtx);
1115 atomic_store_rel_int(&root_mount_complete, 1);
1116 wakeup(&root_mount_complete);
1117 mtx_unlock(&root_holds_mtx);
1118
1119 EVENTHANDLER_INVOKE(mountroot);
1120
1121 TSEXIT();
1122 }
1123
1124 static struct mntarg *
1125 parse_mountroot_options(struct mntarg *ma, const char *options)
1126 {
1127 char *p;
1128 char *name, *name_arg;
1129 char *val, *val_arg;
1130 char *opts;
1131
1132 if (options == NULL || options[0] == '\0')
1133 return (ma);
1134
1135 p = opts = strdup(options, M_MOUNT);
1136 if (opts == NULL) {
1137 return (ma);
1138 }
1139
1140 while((name = strsep(&p, ",")) != NULL) {
1141 if (name[0] == '\0')
1142 break;
1143
1144 val = strchr(name, '=');
1145 if (val != NULL) {
1146 *val = '\0';
1147 ++val;
1148 }
1149 if( strcmp(name, "rw") == 0 ||
1150 strcmp(name, "noro") == 0) {
1151 /*
1152 * The first time we mount the root file system,
1153 * we need to mount 'ro', so We need to ignore
1154 * 'rw' and 'noro' mount options.
1155 */
1156 continue;
1157 }
1158 name_arg = strdup(name, M_MOUNT);
1159 val_arg = NULL;
1160 if (val != NULL)
1161 val_arg = strdup(val, M_MOUNT);
1162
1163 ma = mount_arg(ma, name_arg, val_arg,
1164 (val_arg != NULL ? -1 : 0));
1165 }
1166 free(opts, M_MOUNT);
1167 return (ma);
1168 }
Cache object: bc4c1f6088b7cad0b4126cda81c8aeb0
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