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("$FreeBSD$");
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
89 static int parse_mount(char **);
90 static struct mntarg *parse_mountroot_options(struct mntarg *, const char *);
91 static int sysctl_vfs_root_mount_hold(SYSCTL_HANDLER_ARGS);
92 static int vfs_mountroot_wait_if_neccessary(const char *fs, const char *dev);
93
94 /*
95 * The vnode of the system's root (/ in the filesystem, without chroot
96 * active.)
97 */
98 struct vnode *rootvnode;
99
100 /*
101 * Mount of the system's /dev.
102 */
103 struct mount *rootdevmp;
104
105 char *rootdevnames[2] = {NULL, NULL};
106
107 struct mtx root_holds_mtx;
108 MTX_SYSINIT(root_holds, &root_holds_mtx, "root_holds", MTX_DEF);
109
110 struct root_hold_token {
111 const char *who;
112 LIST_ENTRY(root_hold_token) list;
113 };
114
115 static LIST_HEAD(, root_hold_token) root_holds =
116 LIST_HEAD_INITIALIZER(root_holds);
117
118 enum action {
119 A_CONTINUE,
120 A_PANIC,
121 A_REBOOT,
122 A_RETRY
123 };
124
125 static enum action root_mount_onfail = A_CONTINUE;
126
127 static int root_mount_mddev;
128 static int root_mount_complete;
129
130 /* By default wait up to 3 seconds for devices to appear. */
131 static int root_mount_timeout = 3;
132 TUNABLE_INT("vfs.mountroot.timeout", &root_mount_timeout);
133
134 SYSCTL_PROC(_vfs, OID_AUTO, root_mount_hold,
135 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE,
136 NULL, 0, sysctl_vfs_root_mount_hold, "A",
137 "List of root mount hold tokens");
138
139 static int
sysctl_vfs_root_mount_hold(SYSCTL_HANDLER_ARGS)140 sysctl_vfs_root_mount_hold(SYSCTL_HANDLER_ARGS)
141 {
142 struct sbuf sb;
143 struct root_hold_token *h;
144 int error;
145
146 sbuf_new(&sb, NULL, 256, SBUF_AUTOEXTEND | SBUF_INCLUDENUL);
147
148 mtx_lock(&root_holds_mtx);
149 LIST_FOREACH(h, &root_holds, list) {
150 if (h != LIST_FIRST(&root_holds))
151 sbuf_putc(&sb, ' ');
152 sbuf_printf(&sb, "%s", h->who);
153 }
154 mtx_unlock(&root_holds_mtx);
155
156 error = sbuf_finish(&sb);
157 if (error == 0)
158 error = SYSCTL_OUT(req, sbuf_data(&sb), sbuf_len(&sb));
159 sbuf_delete(&sb);
160 return (error);
161 }
162
163 struct root_hold_token *
root_mount_hold(const char * identifier)164 root_mount_hold(const char *identifier)
165 {
166 struct root_hold_token *h;
167
168 if (root_mounted())
169 return (NULL);
170
171 h = malloc(sizeof *h, M_DEVBUF, M_ZERO | M_WAITOK);
172 h->who = identifier;
173 mtx_lock(&root_holds_mtx);
174 LIST_INSERT_HEAD(&root_holds, h, list);
175 mtx_unlock(&root_holds_mtx);
176 return (h);
177 }
178
179 void
root_mount_rel(struct root_hold_token * h)180 root_mount_rel(struct root_hold_token *h)
181 {
182
183 if (h == NULL)
184 return;
185 mtx_lock(&root_holds_mtx);
186 LIST_REMOVE(h, list);
187 wakeup(&root_holds);
188 mtx_unlock(&root_holds_mtx);
189 free(h, M_DEVBUF);
190 }
191
192 int
root_mounted(void)193 root_mounted(void)
194 {
195
196 /* No mutex is acquired here because int stores are atomic. */
197 return (root_mount_complete);
198 }
199
200 static void
set_rootvnode(void)201 set_rootvnode(void)
202 {
203 struct proc *p;
204
205 if (VFS_ROOT(TAILQ_FIRST(&mountlist), LK_EXCLUSIVE, &rootvnode))
206 panic("Cannot find root vnode");
207
208 VOP_UNLOCK(rootvnode, 0);
209
210 p = curthread->td_proc;
211 FILEDESC_XLOCK(p->p_fd);
212
213 if (p->p_fd->fd_cdir != NULL)
214 vrele(p->p_fd->fd_cdir);
215 p->p_fd->fd_cdir = rootvnode;
216 VREF(rootvnode);
217
218 if (p->p_fd->fd_rdir != NULL)
219 vrele(p->p_fd->fd_rdir);
220 p->p_fd->fd_rdir = rootvnode;
221 VREF(rootvnode);
222
223 FILEDESC_XUNLOCK(p->p_fd);
224 }
225
226 static int
vfs_mountroot_devfs(struct thread * td,struct mount ** mpp)227 vfs_mountroot_devfs(struct thread *td, struct mount **mpp)
228 {
229 struct vfsoptlist *opts;
230 struct vfsconf *vfsp;
231 struct mount *mp;
232 int error;
233
234 *mpp = NULL;
235
236 if (rootdevmp != NULL) {
237 /*
238 * Already have /dev; this happens during rerooting.
239 */
240 error = vfs_busy(rootdevmp, 0);
241 if (error != 0)
242 return (error);
243 *mpp = rootdevmp;
244 } else {
245 vfsp = vfs_byname("devfs");
246 KASSERT(vfsp != NULL, ("Could not find devfs by name"));
247 if (vfsp == NULL)
248 return (ENOENT);
249
250 mp = vfs_mount_alloc(NULLVP, vfsp, "/dev", td->td_ucred);
251
252 error = VFS_MOUNT(mp);
253 KASSERT(error == 0, ("VFS_MOUNT(devfs) failed %d", error));
254 if (error)
255 return (error);
256
257 opts = malloc(sizeof(struct vfsoptlist), M_MOUNT, M_WAITOK);
258 TAILQ_INIT(opts);
259 mp->mnt_opt = opts;
260
261 mtx_lock(&mountlist_mtx);
262 TAILQ_INSERT_HEAD(&mountlist, mp, mnt_list);
263 mtx_unlock(&mountlist_mtx);
264
265 *mpp = mp;
266 rootdevmp = mp;
267 }
268
269 set_rootvnode();
270
271 error = kern_symlinkat(td, "/", AT_FDCWD, "dev", UIO_SYSSPACE);
272 if (error)
273 printf("kern_symlink /dev -> / returns %d\n", error);
274
275 return (error);
276 }
277
278 static void
vfs_mountroot_shuffle(struct thread * td,struct mount * mpdevfs)279 vfs_mountroot_shuffle(struct thread *td, struct mount *mpdevfs)
280 {
281 struct nameidata nd;
282 struct mount *mporoot, *mpnroot;
283 struct vnode *vp, *vporoot, *vpdevfs;
284 char *fspath;
285 int error;
286
287 mpnroot = TAILQ_NEXT(mpdevfs, mnt_list);
288
289 /* Shuffle the mountlist. */
290 mtx_lock(&mountlist_mtx);
291 mporoot = TAILQ_FIRST(&mountlist);
292 TAILQ_REMOVE(&mountlist, mpdevfs, mnt_list);
293 if (mporoot != mpdevfs) {
294 TAILQ_REMOVE(&mountlist, mpnroot, mnt_list);
295 TAILQ_INSERT_HEAD(&mountlist, mpnroot, mnt_list);
296 }
297 TAILQ_INSERT_TAIL(&mountlist, mpdevfs, mnt_list);
298 mtx_unlock(&mountlist_mtx);
299
300 cache_purgevfs(mporoot);
301 if (mporoot != mpdevfs)
302 cache_purgevfs(mpdevfs);
303
304 VFS_ROOT(mporoot, LK_EXCLUSIVE, &vporoot);
305
306 VI_LOCK(vporoot);
307 vporoot->v_iflag &= ~VI_MOUNT;
308 VI_UNLOCK(vporoot);
309 vporoot->v_mountedhere = NULL;
310 mporoot->mnt_flag &= ~MNT_ROOTFS;
311 mporoot->mnt_vnodecovered = NULL;
312 vput(vporoot);
313
314 /* Set up the new rootvnode, and purge the cache */
315 mpnroot->mnt_vnodecovered = NULL;
316 set_rootvnode();
317 cache_purgevfs(rootvnode->v_mount);
318
319 if (mporoot != mpdevfs) {
320 /* Remount old root under /.mount or /mnt */
321 fspath = "/.mount";
322 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE,
323 fspath, td);
324 error = namei(&nd);
325 if (error) {
326 NDFREE(&nd, NDF_ONLY_PNBUF);
327 fspath = "/mnt";
328 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE,
329 fspath, td);
330 error = namei(&nd);
331 }
332 if (!error) {
333 vp = nd.ni_vp;
334 error = (vp->v_type == VDIR) ? 0 : ENOTDIR;
335 if (!error)
336 error = vinvalbuf(vp, V_SAVE, 0, 0);
337 if (!error) {
338 cache_purge(vp);
339 mporoot->mnt_vnodecovered = vp;
340 vp->v_mountedhere = mporoot;
341 strlcpy(mporoot->mnt_stat.f_mntonname,
342 fspath, MNAMELEN);
343 VOP_UNLOCK(vp, 0);
344 } else
345 vput(vp);
346 }
347 NDFREE(&nd, NDF_ONLY_PNBUF);
348
349 if (error && bootverbose)
350 printf("mountroot: unable to remount previous root "
351 "under /.mount or /mnt (error %d).\n", error);
352 }
353
354 /* Remount devfs under /dev */
355 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, "/dev", td);
356 error = namei(&nd);
357 if (!error) {
358 vp = nd.ni_vp;
359 error = (vp->v_type == VDIR) ? 0 : ENOTDIR;
360 if (!error)
361 error = vinvalbuf(vp, V_SAVE, 0, 0);
362 if (!error) {
363 vpdevfs = mpdevfs->mnt_vnodecovered;
364 if (vpdevfs != NULL) {
365 cache_purge(vpdevfs);
366 vpdevfs->v_mountedhere = NULL;
367 vrele(vpdevfs);
368 }
369 mpdevfs->mnt_vnodecovered = vp;
370 vp->v_mountedhere = mpdevfs;
371 VOP_UNLOCK(vp, 0);
372 } else
373 vput(vp);
374 }
375 if (error && bootverbose)
376 printf("mountroot: unable to remount devfs under /dev "
377 "(error %d).\n", error);
378 NDFREE(&nd, NDF_ONLY_PNBUF);
379
380 if (mporoot == mpdevfs) {
381 vfs_unbusy(mpdevfs);
382 /* Unlink the no longer needed /dev/dev -> / symlink */
383 error = kern_unlinkat(td, AT_FDCWD, "/dev/dev",
384 UIO_SYSSPACE, 0);
385 if (error && bootverbose)
386 printf("mountroot: unable to unlink /dev/dev "
387 "(error %d)\n", error);
388 }
389 }
390
391 /*
392 * Configuration parser.
393 */
394
395 /* Parser character classes. */
396 #define CC_WHITESPACE -1
397 #define CC_NONWHITESPACE -2
398
399 /* Parse errors. */
400 #define PE_EOF -1
401 #define PE_EOL -2
402
403 static __inline int
parse_peek(char ** conf)404 parse_peek(char **conf)
405 {
406
407 return (**conf);
408 }
409
410 static __inline void
parse_poke(char ** conf,int c)411 parse_poke(char **conf, int c)
412 {
413
414 **conf = c;
415 }
416
417 static __inline void
parse_advance(char ** conf)418 parse_advance(char **conf)
419 {
420
421 (*conf)++;
422 }
423
424 static int
parse_skipto(char ** conf,int mc)425 parse_skipto(char **conf, int mc)
426 {
427 int c, match;
428
429 while (1) {
430 c = parse_peek(conf);
431 if (c == 0)
432 return (PE_EOF);
433 switch (mc) {
434 case CC_WHITESPACE:
435 match = (c == ' ' || c == '\t' || c == '\n') ? 1 : 0;
436 break;
437 case CC_NONWHITESPACE:
438 if (c == '\n')
439 return (PE_EOL);
440 match = (c != ' ' && c != '\t') ? 1 : 0;
441 break;
442 default:
443 match = (c == mc) ? 1 : 0;
444 break;
445 }
446 if (match)
447 break;
448 parse_advance(conf);
449 }
450 return (0);
451 }
452
453 static int
parse_token(char ** conf,char ** tok)454 parse_token(char **conf, char **tok)
455 {
456 char *p;
457 size_t len;
458 int error;
459
460 *tok = NULL;
461 error = parse_skipto(conf, CC_NONWHITESPACE);
462 if (error)
463 return (error);
464 p = *conf;
465 error = parse_skipto(conf, CC_WHITESPACE);
466 len = *conf - p;
467 *tok = malloc(len + 1, M_TEMP, M_WAITOK | M_ZERO);
468 bcopy(p, *tok, len);
469 return (0);
470 }
471
472 static void
parse_dir_ask_printenv(const char * var)473 parse_dir_ask_printenv(const char *var)
474 {
475 char *val;
476
477 val = kern_getenv(var);
478 if (val != NULL) {
479 printf(" %s=%s\n", var, val);
480 freeenv(val);
481 }
482 }
483
484 static int
parse_dir_ask(char ** conf)485 parse_dir_ask(char **conf)
486 {
487 char name[80];
488 char *mnt;
489 int error;
490
491 printf("\nLoader variables:\n");
492 parse_dir_ask_printenv("vfs.root.mountfrom");
493 parse_dir_ask_printenv("vfs.root.mountfrom.options");
494
495 printf("\nManual root filesystem specification:\n");
496 printf(" <fstype>:<device> [options]\n");
497 printf(" Mount <device> using filesystem <fstype>\n");
498 printf(" and with the specified (optional) option list.\n");
499 printf("\n");
500 printf(" eg. ufs:/dev/da0s1a\n");
501 printf(" zfs:tank\n");
502 printf(" cd9660:/dev/cd0 ro\n");
503 printf(" (which is equivalent to: ");
504 printf("mount -t cd9660 -o ro /dev/cd0 /)\n");
505 printf("\n");
506 printf(" ? List valid disk boot devices\n");
507 printf(" . Yield 1 second (for background tasks)\n");
508 printf(" <empty line> Abort manual input\n");
509
510 do {
511 error = EINVAL;
512 printf("\nmountroot> ");
513 cngets(name, sizeof(name), GETS_ECHO);
514 if (name[0] == '\0')
515 break;
516 if (name[0] == '?' && name[1] == '\0') {
517 printf("\nList of GEOM managed disk devices:\n ");
518 g_dev_print();
519 continue;
520 }
521 if (name[0] == '.' && name[1] == '\0') {
522 pause("rmask", hz);
523 continue;
524 }
525 mnt = name;
526 error = parse_mount(&mnt);
527 if (error == -1)
528 printf("Invalid file system specification.\n");
529 } while (error != 0);
530
531 return (error);
532 }
533
534 static int
parse_dir_md(char ** conf)535 parse_dir_md(char **conf)
536 {
537 struct stat sb;
538 struct thread *td;
539 struct md_ioctl *mdio;
540 char *path, *tok;
541 int error, fd, len;
542
543 td = curthread;
544
545 error = parse_token(conf, &tok);
546 if (error)
547 return (error);
548
549 len = strlen(tok);
550 mdio = malloc(sizeof(*mdio) + len + 1, M_TEMP, M_WAITOK | M_ZERO);
551 path = (void *)(mdio + 1);
552 bcopy(tok, path, len);
553 free(tok, M_TEMP);
554
555 /* Get file status. */
556 error = kern_statat(td, 0, AT_FDCWD, path, UIO_SYSSPACE, &sb, NULL);
557 if (error)
558 goto out;
559
560 /* Open /dev/mdctl so that we can attach/detach. */
561 error = kern_openat(td, AT_FDCWD, "/dev/" MDCTL_NAME, UIO_SYSSPACE,
562 O_RDWR, 0);
563 if (error)
564 goto out;
565
566 fd = td->td_retval[0];
567 mdio->md_version = MDIOVERSION;
568 mdio->md_type = MD_VNODE;
569
570 if (root_mount_mddev != -1) {
571 mdio->md_unit = root_mount_mddev;
572 DROP_GIANT();
573 error = kern_ioctl(td, fd, MDIOCDETACH, (void *)mdio);
574 PICKUP_GIANT();
575 /* Ignore errors. We don't care. */
576 root_mount_mddev = -1;
577 }
578
579 mdio->md_file = (void *)(mdio + 1);
580 mdio->md_options = MD_AUTOUNIT | MD_READONLY;
581 mdio->md_mediasize = sb.st_size;
582 mdio->md_unit = 0;
583 DROP_GIANT();
584 error = kern_ioctl(td, fd, MDIOCATTACH, (void *)mdio);
585 PICKUP_GIANT();
586 if (error)
587 goto out;
588
589 if (mdio->md_unit > 9) {
590 printf("rootmount: too many md units\n");
591 mdio->md_file = NULL;
592 mdio->md_options = 0;
593 mdio->md_mediasize = 0;
594 DROP_GIANT();
595 error = kern_ioctl(td, fd, MDIOCDETACH, (void *)mdio);
596 PICKUP_GIANT();
597 /* Ignore errors. We don't care. */
598 error = ERANGE;
599 goto out;
600 }
601
602 root_mount_mddev = mdio->md_unit;
603 printf(MD_NAME "%u attached to %s\n", root_mount_mddev, mdio->md_file);
604
605 error = kern_close(td, fd);
606
607 out:
608 free(mdio, M_TEMP);
609 return (error);
610 }
611
612 static int
parse_dir_onfail(char ** conf)613 parse_dir_onfail(char **conf)
614 {
615 char *action;
616 int error;
617
618 error = parse_token(conf, &action);
619 if (error)
620 return (error);
621
622 if (!strcmp(action, "continue"))
623 root_mount_onfail = A_CONTINUE;
624 else if (!strcmp(action, "panic"))
625 root_mount_onfail = A_PANIC;
626 else if (!strcmp(action, "reboot"))
627 root_mount_onfail = A_REBOOT;
628 else if (!strcmp(action, "retry"))
629 root_mount_onfail = A_RETRY;
630 else {
631 printf("rootmount: %s: unknown action\n", action);
632 error = EINVAL;
633 }
634
635 free(action, M_TEMP);
636 return (0);
637 }
638
639 static int
parse_dir_timeout(char ** conf)640 parse_dir_timeout(char **conf)
641 {
642 char *tok, *endtok;
643 long secs;
644 int error;
645
646 error = parse_token(conf, &tok);
647 if (error)
648 return (error);
649
650 secs = strtol(tok, &endtok, 0);
651 error = (secs < 0 || *endtok != '\0') ? EINVAL : 0;
652 if (!error)
653 root_mount_timeout = secs;
654 free(tok, M_TEMP);
655 return (error);
656 }
657
658 static int
parse_directive(char ** conf)659 parse_directive(char **conf)
660 {
661 char *dir;
662 int error;
663
664 error = parse_token(conf, &dir);
665 if (error)
666 return (error);
667
668 if (strcmp(dir, ".ask") == 0)
669 error = parse_dir_ask(conf);
670 else if (strcmp(dir, ".md") == 0)
671 error = parse_dir_md(conf);
672 else if (strcmp(dir, ".onfail") == 0)
673 error = parse_dir_onfail(conf);
674 else if (strcmp(dir, ".timeout") == 0)
675 error = parse_dir_timeout(conf);
676 else {
677 printf("mountroot: invalid directive `%s'\n", dir);
678 /* Ignore the rest of the line. */
679 (void)parse_skipto(conf, '\n');
680 error = EINVAL;
681 }
682 free(dir, M_TEMP);
683 return (error);
684 }
685
686 static int
parse_mount_dev_present(const char * dev)687 parse_mount_dev_present(const char *dev)
688 {
689 struct nameidata nd;
690 int error;
691
692 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, dev, curthread);
693 error = namei(&nd);
694 if (!error)
695 vput(nd.ni_vp);
696 NDFREE(&nd, NDF_ONLY_PNBUF);
697 return (error != 0) ? 0 : 1;
698 }
699
700 #define ERRMSGL 255
701 static int
parse_mount(char ** conf)702 parse_mount(char **conf)
703 {
704 char *errmsg;
705 struct mntarg *ma;
706 char *dev, *fs, *opts, *tok;
707 int error;
708
709 error = parse_token(conf, &tok);
710 if (error)
711 return (error);
712 fs = tok;
713 error = parse_skipto(&tok, ':');
714 if (error) {
715 free(fs, M_TEMP);
716 return (error);
717 }
718 parse_poke(&tok, '\0');
719 parse_advance(&tok);
720 dev = tok;
721
722 if (root_mount_mddev != -1) {
723 /* Handle substitution for the md unit number. */
724 tok = strstr(dev, "md#");
725 if (tok != NULL)
726 tok[2] = '0' + root_mount_mddev;
727 }
728
729 /* Parse options. */
730 error = parse_token(conf, &tok);
731 opts = (error == 0) ? tok : NULL;
732
733 printf("Trying to mount root from %s:%s [%s]...\n", fs, dev,
734 (opts != NULL) ? opts : "");
735
736 errmsg = malloc(ERRMSGL, M_TEMP, M_WAITOK | M_ZERO);
737
738 if (vfs_byname(fs) == NULL) {
739 strlcpy(errmsg, "unknown file system", ERRMSGL);
740 error = ENOENT;
741 goto out;
742 }
743
744 error = vfs_mountroot_wait_if_neccessary(fs, dev);
745 if (error != 0)
746 goto out;
747
748 ma = NULL;
749 ma = mount_arg(ma, "fstype", fs, -1);
750 ma = mount_arg(ma, "fspath", "/", -1);
751 ma = mount_arg(ma, "from", dev, -1);
752 ma = mount_arg(ma, "errmsg", errmsg, ERRMSGL);
753 ma = mount_arg(ma, "ro", NULL, 0);
754 ma = parse_mountroot_options(ma, opts);
755 error = kernel_mount(ma, MNT_ROOTFS);
756
757 out:
758 if (error) {
759 printf("Mounting from %s:%s failed with error %d",
760 fs, dev, error);
761 if (errmsg[0] != '\0')
762 printf(": %s", errmsg);
763 printf(".\n");
764 }
765 free(fs, M_TEMP);
766 free(errmsg, M_TEMP);
767 if (opts != NULL)
768 free(opts, M_TEMP);
769 /* kernel_mount can return -1 on error. */
770 return ((error < 0) ? EDOOFUS : error);
771 }
772 #undef ERRMSGL
773
774 static int
vfs_mountroot_parse(struct sbuf * sb,struct mount * mpdevfs)775 vfs_mountroot_parse(struct sbuf *sb, struct mount *mpdevfs)
776 {
777 struct mount *mp;
778 char *conf;
779 int error;
780
781 root_mount_mddev = -1;
782
783 retry:
784 conf = sbuf_data(sb);
785 mp = TAILQ_NEXT(mpdevfs, mnt_list);
786 error = (mp == NULL) ? 0 : EDOOFUS;
787 root_mount_onfail = A_CONTINUE;
788 while (mp == NULL) {
789 error = parse_skipto(&conf, CC_NONWHITESPACE);
790 if (error == PE_EOL) {
791 parse_advance(&conf);
792 continue;
793 }
794 if (error < 0)
795 break;
796 switch (parse_peek(&conf)) {
797 case '#':
798 error = parse_skipto(&conf, '\n');
799 break;
800 case '.':
801 error = parse_directive(&conf);
802 break;
803 default:
804 error = parse_mount(&conf);
805 if (error == -1) {
806 printf("mountroot: invalid file system "
807 "specification.\n");
808 error = 0;
809 }
810 break;
811 }
812 if (error < 0)
813 break;
814 /* Ignore any trailing garbage on the line. */
815 if (parse_peek(&conf) != '\n') {
816 printf("mountroot: advancing to next directive...\n");
817 (void)parse_skipto(&conf, '\n');
818 }
819 mp = TAILQ_NEXT(mpdevfs, mnt_list);
820 }
821 if (mp != NULL)
822 return (0);
823
824 /*
825 * We failed to mount (a new) root.
826 */
827 switch (root_mount_onfail) {
828 case A_CONTINUE:
829 break;
830 case A_PANIC:
831 panic("mountroot: unable to (re-)mount root.");
832 /* NOTREACHED */
833 case A_RETRY:
834 goto retry;
835 case A_REBOOT:
836 kern_reboot(RB_NOSYNC);
837 /* NOTREACHED */
838 }
839
840 return (error);
841 }
842
843 static void
vfs_mountroot_conf0(struct sbuf * sb)844 vfs_mountroot_conf0(struct sbuf *sb)
845 {
846 char *s, *tok, *mnt, *opt;
847 int error;
848
849 sbuf_printf(sb, ".onfail panic\n");
850 sbuf_printf(sb, ".timeout %d\n", root_mount_timeout);
851 if (boothowto & RB_ASKNAME)
852 sbuf_printf(sb, ".ask\n");
853 #ifdef ROOTDEVNAME
854 if (boothowto & RB_DFLTROOT)
855 sbuf_printf(sb, "%s\n", ROOTDEVNAME);
856 #endif
857 if (boothowto & RB_CDROM) {
858 sbuf_printf(sb, "cd9660:/dev/cd0 ro\n");
859 sbuf_printf(sb, ".timeout 0\n");
860 sbuf_printf(sb, "cd9660:/dev/cd1 ro\n");
861 sbuf_printf(sb, ".timeout %d\n", root_mount_timeout);
862 }
863 s = kern_getenv("vfs.root.mountfrom");
864 if (s != NULL) {
865 opt = kern_getenv("vfs.root.mountfrom.options");
866 tok = s;
867 error = parse_token(&tok, &mnt);
868 while (!error) {
869 sbuf_printf(sb, "%s %s\n", mnt,
870 (opt != NULL) ? opt : "");
871 free(mnt, M_TEMP);
872 error = parse_token(&tok, &mnt);
873 }
874 if (opt != NULL)
875 freeenv(opt);
876 freeenv(s);
877 }
878 if (rootdevnames[0] != NULL)
879 sbuf_printf(sb, "%s\n", rootdevnames[0]);
880 if (rootdevnames[1] != NULL)
881 sbuf_printf(sb, "%s\n", rootdevnames[1]);
882 #ifdef ROOTDEVNAME
883 if (!(boothowto & RB_DFLTROOT))
884 sbuf_printf(sb, "%s\n", ROOTDEVNAME);
885 #endif
886 if (!(boothowto & RB_ASKNAME))
887 sbuf_printf(sb, ".ask\n");
888 }
889
890 static int
vfs_mountroot_readconf(struct thread * td,struct sbuf * sb)891 vfs_mountroot_readconf(struct thread *td, struct sbuf *sb)
892 {
893 static char buf[128];
894 struct nameidata nd;
895 off_t ofs;
896 ssize_t resid;
897 int error, flags, len;
898
899 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, "/.mount.conf", td);
900 flags = FREAD;
901 error = vn_open(&nd, &flags, 0, NULL);
902 if (error)
903 return (error);
904
905 NDFREE(&nd, NDF_ONLY_PNBUF);
906 ofs = 0;
907 len = sizeof(buf) - 1;
908 while (1) {
909 error = vn_rdwr(UIO_READ, nd.ni_vp, buf, len, ofs,
910 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred,
911 NOCRED, &resid, td);
912 if (error)
913 break;
914 if (resid == len)
915 break;
916 buf[len - resid] = 0;
917 sbuf_printf(sb, "%s", buf);
918 ofs += len - resid;
919 }
920
921 VOP_UNLOCK(nd.ni_vp, 0);
922 vn_close(nd.ni_vp, FREAD, td->td_ucred, td);
923 return (error);
924 }
925
926 static void
vfs_mountroot_wait(void)927 vfs_mountroot_wait(void)
928 {
929 struct root_hold_token *h;
930 struct timeval lastfail;
931 int curfail;
932
933 curfail = 0;
934 while (1) {
935 DROP_GIANT();
936 g_waitidle();
937 PICKUP_GIANT();
938 mtx_lock(&root_holds_mtx);
939 if (LIST_EMPTY(&root_holds)) {
940 mtx_unlock(&root_holds_mtx);
941 break;
942 }
943 if (ppsratecheck(&lastfail, &curfail, 1)) {
944 printf("Root mount waiting for:");
945 LIST_FOREACH(h, &root_holds, list)
946 printf(" %s", h->who);
947 printf("\n");
948 }
949 msleep(&root_holds, &root_holds_mtx, PZERO | PDROP, "roothold",
950 hz);
951 }
952 }
953
954 static int
vfs_mountroot_wait_if_neccessary(const char * fs,const char * dev)955 vfs_mountroot_wait_if_neccessary(const char *fs, const char *dev)
956 {
957 int delay, timeout;
958
959 /*
960 * In case of ZFS and NFS we don't have a way to wait for
961 * specific device.
962 */
963 if (strcmp(fs, "zfs") == 0 || strstr(fs, "nfs") != NULL ||
964 dev[0] == '\0') {
965 vfs_mountroot_wait();
966 return (0);
967 }
968
969 /*
970 * Otherwise, no point in waiting if the device is already there.
971 * Note that we must wait for GEOM to finish reconfiguring itself,
972 * eg for geom_part(4) to finish tasting.
973 */
974 DROP_GIANT();
975 g_waitidle();
976 PICKUP_GIANT();
977 if (parse_mount_dev_present(dev))
978 return (0);
979
980 /*
981 * No luck. Let's wait. This code looks weird, but it's that way
982 * to behave exactly as it used to work before.
983 */
984 vfs_mountroot_wait();
985 printf("mountroot: waiting for device %s...\n", dev);
986 delay = hz / 10;
987 timeout = root_mount_timeout * hz;
988 do {
989 pause("rmdev", delay);
990 timeout -= delay;
991 } while (timeout > 0 && !parse_mount_dev_present(dev));
992
993 if (timeout <= 0)
994 return (ENODEV);
995
996 return (0);
997 }
998
999 void
vfs_mountroot(void)1000 vfs_mountroot(void)
1001 {
1002 struct mount *mp;
1003 struct sbuf *sb;
1004 struct thread *td;
1005 time_t timebase;
1006 int error;
1007
1008 td = curthread;
1009
1010 sb = sbuf_new_auto();
1011 vfs_mountroot_conf0(sb);
1012 sbuf_finish(sb);
1013
1014 error = vfs_mountroot_devfs(td, &mp);
1015 while (!error) {
1016 error = vfs_mountroot_parse(sb, mp);
1017 if (!error) {
1018 vfs_mountroot_shuffle(td, mp);
1019 sbuf_clear(sb);
1020 error = vfs_mountroot_readconf(td, sb);
1021 sbuf_finish(sb);
1022 }
1023 }
1024
1025 sbuf_delete(sb);
1026
1027 /*
1028 * Iterate over all currently mounted file systems and use
1029 * the time stamp found to check and/or initialize the RTC.
1030 * Call inittodr() only once and pass it the largest of the
1031 * timestamps we encounter.
1032 */
1033 timebase = 0;
1034 mtx_lock(&mountlist_mtx);
1035 mp = TAILQ_FIRST(&mountlist);
1036 while (mp != NULL) {
1037 if (mp->mnt_time > timebase)
1038 timebase = mp->mnt_time;
1039 mp = TAILQ_NEXT(mp, mnt_list);
1040 }
1041 mtx_unlock(&mountlist_mtx);
1042 inittodr(timebase);
1043
1044 /* Keep prison0's root in sync with the global rootvnode. */
1045 mtx_lock(&prison0.pr_mtx);
1046 prison0.pr_root = rootvnode;
1047 vref(prison0.pr_root);
1048 mtx_unlock(&prison0.pr_mtx);
1049
1050 mtx_lock(&root_holds_mtx);
1051 atomic_store_rel_int(&root_mount_complete, 1);
1052 wakeup(&root_mount_complete);
1053 mtx_unlock(&root_holds_mtx);
1054
1055 EVENTHANDLER_INVOKE(mountroot);
1056 }
1057
1058 static struct mntarg *
parse_mountroot_options(struct mntarg * ma,const char * options)1059 parse_mountroot_options(struct mntarg *ma, const char *options)
1060 {
1061 char *p;
1062 char *name, *name_arg;
1063 char *val, *val_arg;
1064 char *opts;
1065
1066 if (options == NULL || options[0] == '\0')
1067 return (ma);
1068
1069 p = opts = strdup(options, M_MOUNT);
1070 if (opts == NULL) {
1071 return (ma);
1072 }
1073
1074 while((name = strsep(&p, ",")) != NULL) {
1075 if (name[0] == '\0')
1076 break;
1077
1078 val = strchr(name, '=');
1079 if (val != NULL) {
1080 *val = '\0';
1081 ++val;
1082 }
1083 if( strcmp(name, "rw") == 0 ||
1084 strcmp(name, "noro") == 0) {
1085 /*
1086 * The first time we mount the root file system,
1087 * we need to mount 'ro', so We need to ignore
1088 * 'rw' and 'noro' mount options.
1089 */
1090 continue;
1091 }
1092 name_arg = strdup(name, M_MOUNT);
1093 val_arg = NULL;
1094 if (val != NULL)
1095 val_arg = strdup(val, M_MOUNT);
1096
1097 ma = mount_arg(ma, name_arg, val_arg,
1098 (val_arg != NULL ? -1 : 0));
1099 }
1100 free(opts, M_MOUNT);
1101 return (ma);
1102 }
1103