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: releng/10.2/sys/kern/vfs_mountroot.c 267752 2014-06-22 21:21:27Z mav $");
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
92 /*
93 * The vnode of the system's root (/ in the filesystem, without chroot
94 * active.)
95 */
96 struct vnode *rootvnode;
97
98 char *rootdevnames[2] = {NULL, NULL};
99
100 struct mtx root_holds_mtx;
101 MTX_SYSINIT(root_holds, &root_holds_mtx, "root_holds", MTX_DEF);
102
103 struct root_hold_token {
104 const char *who;
105 LIST_ENTRY(root_hold_token) list;
106 };
107
108 static LIST_HEAD(, root_hold_token) root_holds =
109 LIST_HEAD_INITIALIZER(root_holds);
110
111 enum action {
112 A_CONTINUE,
113 A_PANIC,
114 A_REBOOT,
115 A_RETRY
116 };
117
118 static enum action root_mount_onfail = A_CONTINUE;
119
120 static int root_mount_mddev;
121 static int root_mount_complete;
122
123 /* By default wait up to 3 seconds for devices to appear. */
124 static int root_mount_timeout = 3;
125 TUNABLE_INT("vfs.mountroot.timeout", &root_mount_timeout);
126
127 struct root_hold_token *
128 root_mount_hold(const char *identifier)
129 {
130 struct root_hold_token *h;
131
132 if (root_mounted())
133 return (NULL);
134
135 h = malloc(sizeof *h, M_DEVBUF, M_ZERO | M_WAITOK);
136 h->who = identifier;
137 mtx_lock(&root_holds_mtx);
138 LIST_INSERT_HEAD(&root_holds, h, list);
139 mtx_unlock(&root_holds_mtx);
140 return (h);
141 }
142
143 void
144 root_mount_rel(struct root_hold_token *h)
145 {
146
147 if (h == NULL)
148 return;
149 mtx_lock(&root_holds_mtx);
150 LIST_REMOVE(h, list);
151 wakeup(&root_holds);
152 mtx_unlock(&root_holds_mtx);
153 free(h, M_DEVBUF);
154 }
155
156 int
157 root_mounted(void)
158 {
159
160 /* No mutex is acquired here because int stores are atomic. */
161 return (root_mount_complete);
162 }
163
164 void
165 root_mount_wait(void)
166 {
167
168 /*
169 * Panic on an obvious deadlock - the function can't be called from
170 * a thread which is doing the whole SYSINIT stuff.
171 */
172 KASSERT(curthread->td_proc->p_pid != 0,
173 ("root_mount_wait: cannot be called from the swapper thread"));
174 mtx_lock(&root_holds_mtx);
175 while (!root_mount_complete) {
176 msleep(&root_mount_complete, &root_holds_mtx, PZERO, "rootwait",
177 hz);
178 }
179 mtx_unlock(&root_holds_mtx);
180 }
181
182 static void
183 set_rootvnode(void)
184 {
185 struct proc *p;
186
187 if (VFS_ROOT(TAILQ_FIRST(&mountlist), LK_EXCLUSIVE, &rootvnode))
188 panic("Cannot find root vnode");
189
190 VOP_UNLOCK(rootvnode, 0);
191
192 p = curthread->td_proc;
193 FILEDESC_XLOCK(p->p_fd);
194
195 if (p->p_fd->fd_cdir != NULL)
196 vrele(p->p_fd->fd_cdir);
197 p->p_fd->fd_cdir = rootvnode;
198 VREF(rootvnode);
199
200 if (p->p_fd->fd_rdir != NULL)
201 vrele(p->p_fd->fd_rdir);
202 p->p_fd->fd_rdir = rootvnode;
203 VREF(rootvnode);
204
205 FILEDESC_XUNLOCK(p->p_fd);
206 }
207
208 static int
209 vfs_mountroot_devfs(struct thread *td, struct mount **mpp)
210 {
211 struct vfsoptlist *opts;
212 struct vfsconf *vfsp;
213 struct mount *mp;
214 int error;
215
216 *mpp = NULL;
217
218 vfsp = vfs_byname("devfs");
219 KASSERT(vfsp != NULL, ("Could not find devfs by name"));
220 if (vfsp == NULL)
221 return (ENOENT);
222
223 mp = vfs_mount_alloc(NULLVP, vfsp, "/dev", td->td_ucred);
224
225 error = VFS_MOUNT(mp);
226 KASSERT(error == 0, ("VFS_MOUNT(devfs) failed %d", error));
227 if (error)
228 return (error);
229
230 opts = malloc(sizeof(struct vfsoptlist), M_MOUNT, M_WAITOK);
231 TAILQ_INIT(opts);
232 mp->mnt_opt = opts;
233
234 mtx_lock(&mountlist_mtx);
235 TAILQ_INSERT_HEAD(&mountlist, mp, mnt_list);
236 mtx_unlock(&mountlist_mtx);
237
238 *mpp = mp;
239 set_rootvnode();
240
241 error = kern_symlink(td, "/", "dev", UIO_SYSSPACE);
242 if (error)
243 printf("kern_symlink /dev -> / returns %d\n", error);
244
245 return (error);
246 }
247
248 static int
249 vfs_mountroot_shuffle(struct thread *td, struct mount *mpdevfs)
250 {
251 struct nameidata nd;
252 struct mount *mporoot, *mpnroot;
253 struct vnode *vp, *vporoot, *vpdevfs;
254 char *fspath;
255 int error;
256
257 mpnroot = TAILQ_NEXT(mpdevfs, mnt_list);
258
259 /* Shuffle the mountlist. */
260 mtx_lock(&mountlist_mtx);
261 mporoot = TAILQ_FIRST(&mountlist);
262 TAILQ_REMOVE(&mountlist, mpdevfs, mnt_list);
263 if (mporoot != mpdevfs) {
264 TAILQ_REMOVE(&mountlist, mpnroot, mnt_list);
265 TAILQ_INSERT_HEAD(&mountlist, mpnroot, mnt_list);
266 }
267 TAILQ_INSERT_TAIL(&mountlist, mpdevfs, mnt_list);
268 mtx_unlock(&mountlist_mtx);
269
270 cache_purgevfs(mporoot);
271 if (mporoot != mpdevfs)
272 cache_purgevfs(mpdevfs);
273
274 VFS_ROOT(mporoot, LK_EXCLUSIVE, &vporoot);
275
276 VI_LOCK(vporoot);
277 vporoot->v_iflag &= ~VI_MOUNT;
278 VI_UNLOCK(vporoot);
279 vporoot->v_mountedhere = NULL;
280 mporoot->mnt_flag &= ~MNT_ROOTFS;
281 mporoot->mnt_vnodecovered = NULL;
282 vput(vporoot);
283
284 /* Set up the new rootvnode, and purge the cache */
285 mpnroot->mnt_vnodecovered = NULL;
286 set_rootvnode();
287 cache_purgevfs(rootvnode->v_mount);
288
289 if (mporoot != mpdevfs) {
290 /* Remount old root under /.mount or /mnt */
291 fspath = "/.mount";
292 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE,
293 fspath, td);
294 error = namei(&nd);
295 if (error) {
296 NDFREE(&nd, NDF_ONLY_PNBUF);
297 fspath = "/mnt";
298 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE,
299 fspath, td);
300 error = namei(&nd);
301 }
302 if (!error) {
303 vp = nd.ni_vp;
304 error = (vp->v_type == VDIR) ? 0 : ENOTDIR;
305 if (!error)
306 error = vinvalbuf(vp, V_SAVE, 0, 0);
307 if (!error) {
308 cache_purge(vp);
309 mporoot->mnt_vnodecovered = vp;
310 vp->v_mountedhere = mporoot;
311 strlcpy(mporoot->mnt_stat.f_mntonname,
312 fspath, MNAMELEN);
313 VOP_UNLOCK(vp, 0);
314 } else
315 vput(vp);
316 }
317 NDFREE(&nd, NDF_ONLY_PNBUF);
318
319 if (error && bootverbose)
320 printf("mountroot: unable to remount previous root "
321 "under /.mount or /mnt (error %d).\n", error);
322 }
323
324 /* Remount devfs under /dev */
325 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, "/dev", td);
326 error = namei(&nd);
327 if (!error) {
328 vp = nd.ni_vp;
329 error = (vp->v_type == VDIR) ? 0 : ENOTDIR;
330 if (!error)
331 error = vinvalbuf(vp, V_SAVE, 0, 0);
332 if (!error) {
333 vpdevfs = mpdevfs->mnt_vnodecovered;
334 if (vpdevfs != NULL) {
335 cache_purge(vpdevfs);
336 vpdevfs->v_mountedhere = NULL;
337 vrele(vpdevfs);
338 }
339 mpdevfs->mnt_vnodecovered = vp;
340 vp->v_mountedhere = mpdevfs;
341 VOP_UNLOCK(vp, 0);
342 } else
343 vput(vp);
344 }
345 if (error && bootverbose)
346 printf("mountroot: unable to remount devfs under /dev "
347 "(error %d).\n", error);
348 NDFREE(&nd, NDF_ONLY_PNBUF);
349
350 if (mporoot == mpdevfs) {
351 vfs_unbusy(mpdevfs);
352 /* Unlink the no longer needed /dev/dev -> / symlink */
353 error = kern_unlink(td, "/dev/dev", UIO_SYSSPACE);
354 if (error && bootverbose)
355 printf("mountroot: unable to unlink /dev/dev "
356 "(error %d)\n", error);
357 }
358
359 return (0);
360 }
361
362 /*
363 * Configuration parser.
364 */
365
366 /* Parser character classes. */
367 #define CC_WHITESPACE -1
368 #define CC_NONWHITESPACE -2
369
370 /* Parse errors. */
371 #define PE_EOF -1
372 #define PE_EOL -2
373
374 static __inline int
375 parse_peek(char **conf)
376 {
377
378 return (**conf);
379 }
380
381 static __inline void
382 parse_poke(char **conf, int c)
383 {
384
385 **conf = c;
386 }
387
388 static __inline void
389 parse_advance(char **conf)
390 {
391
392 (*conf)++;
393 }
394
395 static int
396 parse_skipto(char **conf, int mc)
397 {
398 int c, match;
399
400 while (1) {
401 c = parse_peek(conf);
402 if (c == 0)
403 return (PE_EOF);
404 switch (mc) {
405 case CC_WHITESPACE:
406 match = (c == ' ' || c == '\t' || c == '\n') ? 1 : 0;
407 break;
408 case CC_NONWHITESPACE:
409 if (c == '\n')
410 return (PE_EOL);
411 match = (c != ' ' && c != '\t') ? 1 : 0;
412 break;
413 default:
414 match = (c == mc) ? 1 : 0;
415 break;
416 }
417 if (match)
418 break;
419 parse_advance(conf);
420 }
421 return (0);
422 }
423
424 static int
425 parse_token(char **conf, char **tok)
426 {
427 char *p;
428 size_t len;
429 int error;
430
431 *tok = NULL;
432 error = parse_skipto(conf, CC_NONWHITESPACE);
433 if (error)
434 return (error);
435 p = *conf;
436 error = parse_skipto(conf, CC_WHITESPACE);
437 len = *conf - p;
438 *tok = malloc(len + 1, M_TEMP, M_WAITOK | M_ZERO);
439 bcopy(p, *tok, len);
440 return (0);
441 }
442
443 static void
444 parse_dir_ask_printenv(const char *var)
445 {
446 char *val;
447
448 val = getenv(var);
449 if (val != NULL) {
450 printf(" %s=%s\n", var, val);
451 freeenv(val);
452 }
453 }
454
455 static int
456 parse_dir_ask(char **conf)
457 {
458 char name[80];
459 char *mnt;
460 int error;
461
462 printf("\nLoader variables:\n");
463 parse_dir_ask_printenv("vfs.root.mountfrom");
464 parse_dir_ask_printenv("vfs.root.mountfrom.options");
465
466 printf("\nManual root filesystem specification:\n");
467 printf(" <fstype>:<device> [options]\n");
468 printf(" Mount <device> using filesystem <fstype>\n");
469 printf(" and with the specified (optional) option list.\n");
470 printf("\n");
471 printf(" eg. ufs:/dev/da0s1a\n");
472 printf(" zfs:tank\n");
473 printf(" cd9660:/dev/acd0 ro\n");
474 printf(" (which is equivalent to: ");
475 printf("mount -t cd9660 -o ro /dev/acd0 /)\n");
476 printf("\n");
477 printf(" ? List valid disk boot devices\n");
478 printf(" . Yield 1 second (for background tasks)\n");
479 printf(" <empty line> Abort manual input\n");
480
481 do {
482 error = EINVAL;
483 printf("\nmountroot> ");
484 cngets(name, sizeof(name), GETS_ECHO);
485 if (name[0] == '\0')
486 break;
487 if (name[0] == '?' && name[1] == '\0') {
488 printf("\nList of GEOM managed disk devices:\n ");
489 g_dev_print();
490 continue;
491 }
492 if (name[0] == '.' && name[1] == '\0') {
493 pause("rmask", hz);
494 continue;
495 }
496 mnt = name;
497 error = parse_mount(&mnt);
498 if (error == -1)
499 printf("Invalid file system specification.\n");
500 } while (error != 0);
501
502 return (error);
503 }
504
505 static int
506 parse_dir_md(char **conf)
507 {
508 struct stat sb;
509 struct thread *td;
510 struct md_ioctl *mdio;
511 char *path, *tok;
512 int error, fd, len;
513
514 td = curthread;
515
516 error = parse_token(conf, &tok);
517 if (error)
518 return (error);
519
520 len = strlen(tok);
521 mdio = malloc(sizeof(*mdio) + len + 1, M_TEMP, M_WAITOK | M_ZERO);
522 path = (void *)(mdio + 1);
523 bcopy(tok, path, len);
524 free(tok, M_TEMP);
525
526 /* Get file status. */
527 error = kern_stat(td, path, UIO_SYSSPACE, &sb);
528 if (error)
529 goto out;
530
531 /* Open /dev/mdctl so that we can attach/detach. */
532 error = kern_open(td, "/dev/" MDCTL_NAME, UIO_SYSSPACE, O_RDWR, 0);
533 if (error)
534 goto out;
535
536 fd = td->td_retval[0];
537 mdio->md_version = MDIOVERSION;
538 mdio->md_type = MD_VNODE;
539
540 if (root_mount_mddev != -1) {
541 mdio->md_unit = root_mount_mddev;
542 DROP_GIANT();
543 error = kern_ioctl(td, fd, MDIOCDETACH, (void *)mdio);
544 PICKUP_GIANT();
545 /* Ignore errors. We don't care. */
546 root_mount_mddev = -1;
547 }
548
549 mdio->md_file = (void *)(mdio + 1);
550 mdio->md_options = MD_AUTOUNIT | MD_READONLY;
551 mdio->md_mediasize = sb.st_size;
552 mdio->md_unit = 0;
553 DROP_GIANT();
554 error = kern_ioctl(td, fd, MDIOCATTACH, (void *)mdio);
555 PICKUP_GIANT();
556 if (error)
557 goto out;
558
559 if (mdio->md_unit > 9) {
560 printf("rootmount: too many md units\n");
561 mdio->md_file = NULL;
562 mdio->md_options = 0;
563 mdio->md_mediasize = 0;
564 DROP_GIANT();
565 error = kern_ioctl(td, fd, MDIOCDETACH, (void *)mdio);
566 PICKUP_GIANT();
567 /* Ignore errors. We don't care. */
568 error = ERANGE;
569 goto out;
570 }
571
572 root_mount_mddev = mdio->md_unit;
573 printf(MD_NAME "%u attached to %s\n", root_mount_mddev, mdio->md_file);
574
575 error = kern_close(td, fd);
576
577 out:
578 free(mdio, M_TEMP);
579 return (error);
580 }
581
582 static int
583 parse_dir_onfail(char **conf)
584 {
585 char *action;
586 int error;
587
588 error = parse_token(conf, &action);
589 if (error)
590 return (error);
591
592 if (!strcmp(action, "continue"))
593 root_mount_onfail = A_CONTINUE;
594 else if (!strcmp(action, "panic"))
595 root_mount_onfail = A_PANIC;
596 else if (!strcmp(action, "reboot"))
597 root_mount_onfail = A_REBOOT;
598 else if (!strcmp(action, "retry"))
599 root_mount_onfail = A_RETRY;
600 else {
601 printf("rootmount: %s: unknown action\n", action);
602 error = EINVAL;
603 }
604
605 free(action, M_TEMP);
606 return (0);
607 }
608
609 static int
610 parse_dir_timeout(char **conf)
611 {
612 char *tok, *endtok;
613 long secs;
614 int error;
615
616 error = parse_token(conf, &tok);
617 if (error)
618 return (error);
619
620 secs = strtol(tok, &endtok, 0);
621 error = (secs < 0 || *endtok != '\0') ? EINVAL : 0;
622 if (!error)
623 root_mount_timeout = secs;
624 free(tok, M_TEMP);
625 return (error);
626 }
627
628 static int
629 parse_directive(char **conf)
630 {
631 char *dir;
632 int error;
633
634 error = parse_token(conf, &dir);
635 if (error)
636 return (error);
637
638 if (strcmp(dir, ".ask") == 0)
639 error = parse_dir_ask(conf);
640 else if (strcmp(dir, ".md") == 0)
641 error = parse_dir_md(conf);
642 else if (strcmp(dir, ".onfail") == 0)
643 error = parse_dir_onfail(conf);
644 else if (strcmp(dir, ".timeout") == 0)
645 error = parse_dir_timeout(conf);
646 else {
647 printf("mountroot: invalid directive `%s'\n", dir);
648 /* Ignore the rest of the line. */
649 (void)parse_skipto(conf, '\n');
650 error = EINVAL;
651 }
652 free(dir, M_TEMP);
653 return (error);
654 }
655
656 static int
657 parse_mount_dev_present(const char *dev)
658 {
659 struct nameidata nd;
660 int error;
661
662 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, dev, curthread);
663 error = namei(&nd);
664 if (!error)
665 vput(nd.ni_vp);
666 NDFREE(&nd, NDF_ONLY_PNBUF);
667 return (error != 0) ? 0 : 1;
668 }
669
670 #define ERRMSGL 255
671 static int
672 parse_mount(char **conf)
673 {
674 char *errmsg;
675 struct mntarg *ma;
676 char *dev, *fs, *opts, *tok;
677 int delay, error, timeout;
678
679 error = parse_token(conf, &tok);
680 if (error)
681 return (error);
682 fs = tok;
683 error = parse_skipto(&tok, ':');
684 if (error) {
685 free(fs, M_TEMP);
686 return (error);
687 }
688 parse_poke(&tok, '\0');
689 parse_advance(&tok);
690 dev = tok;
691
692 if (root_mount_mddev != -1) {
693 /* Handle substitution for the md unit number. */
694 tok = strstr(dev, "md#");
695 if (tok != NULL)
696 tok[2] = '' + root_mount_mddev;
697 }
698
699 /* Parse options. */
700 error = parse_token(conf, &tok);
701 opts = (error == 0) ? tok : NULL;
702
703 printf("Trying to mount root from %s:%s [%s]...\n", fs, dev,
704 (opts != NULL) ? opts : "");
705
706 errmsg = malloc(ERRMSGL, M_TEMP, M_WAITOK | M_ZERO);
707
708 if (vfs_byname(fs) == NULL) {
709 strlcpy(errmsg, "unknown file system", ERRMSGL);
710 error = ENOENT;
711 goto out;
712 }
713
714 if (strcmp(fs, "zfs") != 0 && strstr(fs, "nfs") == NULL &&
715 dev[0] != '\0' && !parse_mount_dev_present(dev)) {
716 printf("mountroot: waiting for device %s ...\n", dev);
717 delay = hz / 10;
718 timeout = root_mount_timeout * hz;
719 do {
720 pause("rmdev", delay);
721 timeout -= delay;
722 } while (timeout > 0 && !parse_mount_dev_present(dev));
723 if (timeout <= 0) {
724 error = ENODEV;
725 goto out;
726 }
727 }
728
729 ma = NULL;
730 ma = mount_arg(ma, "fstype", fs, -1);
731 ma = mount_arg(ma, "fspath", "/", -1);
732 ma = mount_arg(ma, "from", dev, -1);
733 ma = mount_arg(ma, "errmsg", errmsg, ERRMSGL);
734 ma = mount_arg(ma, "ro", NULL, 0);
735 ma = parse_mountroot_options(ma, opts);
736 error = kernel_mount(ma, MNT_ROOTFS);
737
738 out:
739 if (error) {
740 printf("Mounting from %s:%s failed with error %d",
741 fs, dev, error);
742 if (errmsg[0] != '\0')
743 printf(": %s", errmsg);
744 printf(".\n");
745 }
746 free(fs, M_TEMP);
747 free(errmsg, M_TEMP);
748 if (opts != NULL)
749 free(opts, M_TEMP);
750 /* kernel_mount can return -1 on error. */
751 return ((error < 0) ? EDOOFUS : error);
752 }
753 #undef ERRMSGL
754
755 static int
756 vfs_mountroot_parse(struct sbuf *sb, struct mount *mpdevfs)
757 {
758 struct mount *mp;
759 char *conf;
760 int error;
761
762 root_mount_mddev = -1;
763
764 retry:
765 conf = sbuf_data(sb);
766 mp = TAILQ_NEXT(mpdevfs, mnt_list);
767 error = (mp == NULL) ? 0 : EDOOFUS;
768 root_mount_onfail = A_CONTINUE;
769 while (mp == NULL) {
770 error = parse_skipto(&conf, CC_NONWHITESPACE);
771 if (error == PE_EOL) {
772 parse_advance(&conf);
773 continue;
774 }
775 if (error < 0)
776 break;
777 switch (parse_peek(&conf)) {
778 case '#':
779 error = parse_skipto(&conf, '\n');
780 break;
781 case '.':
782 error = parse_directive(&conf);
783 break;
784 default:
785 error = parse_mount(&conf);
786 break;
787 }
788 if (error < 0)
789 break;
790 /* Ignore any trailing garbage on the line. */
791 if (parse_peek(&conf) != '\n') {
792 printf("mountroot: advancing to next directive...\n");
793 (void)parse_skipto(&conf, '\n');
794 }
795 mp = TAILQ_NEXT(mpdevfs, mnt_list);
796 }
797 if (mp != NULL)
798 return (0);
799
800 /*
801 * We failed to mount (a new) root.
802 */
803 switch (root_mount_onfail) {
804 case A_CONTINUE:
805 break;
806 case A_PANIC:
807 panic("mountroot: unable to (re-)mount root.");
808 /* NOTREACHED */
809 case A_RETRY:
810 goto retry;
811 case A_REBOOT:
812 kern_reboot(RB_NOSYNC);
813 /* NOTREACHED */
814 }
815
816 return (error);
817 }
818
819 static void
820 vfs_mountroot_conf0(struct sbuf *sb)
821 {
822 char *s, *tok, *mnt, *opt;
823 int error;
824
825 sbuf_printf(sb, ".onfail panic\n");
826 sbuf_printf(sb, ".timeout %d\n", root_mount_timeout);
827 if (boothowto & RB_ASKNAME)
828 sbuf_printf(sb, ".ask\n");
829 #ifdef ROOTDEVNAME
830 if (boothowto & RB_DFLTROOT)
831 sbuf_printf(sb, "%s\n", ROOTDEVNAME);
832 #endif
833 if (boothowto & RB_CDROM) {
834 sbuf_printf(sb, "cd9660:/dev/cd0 ro\n");
835 sbuf_printf(sb, ".timeout 0\n");
836 sbuf_printf(sb, "cd9660:/dev/acd0 ro\n");
837 sbuf_printf(sb, ".timeout %d\n", root_mount_timeout);
838 }
839 s = getenv("vfs.root.mountfrom");
840 if (s != NULL) {
841 opt = getenv("vfs.root.mountfrom.options");
842 tok = s;
843 error = parse_token(&tok, &mnt);
844 while (!error) {
845 sbuf_printf(sb, "%s %s\n", mnt,
846 (opt != NULL) ? opt : "");
847 free(mnt, M_TEMP);
848 error = parse_token(&tok, &mnt);
849 }
850 if (opt != NULL)
851 freeenv(opt);
852 freeenv(s);
853 }
854 if (rootdevnames[0] != NULL)
855 sbuf_printf(sb, "%s\n", rootdevnames[0]);
856 if (rootdevnames[1] != NULL)
857 sbuf_printf(sb, "%s\n", rootdevnames[1]);
858 #ifdef ROOTDEVNAME
859 if (!(boothowto & RB_DFLTROOT))
860 sbuf_printf(sb, "%s\n", ROOTDEVNAME);
861 #endif
862 if (!(boothowto & RB_ASKNAME))
863 sbuf_printf(sb, ".ask\n");
864 }
865
866 static int
867 vfs_mountroot_readconf(struct thread *td, struct sbuf *sb)
868 {
869 static char buf[128];
870 struct nameidata nd;
871 off_t ofs;
872 ssize_t resid;
873 int error, flags, len;
874
875 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, "/.mount.conf", td);
876 flags = FREAD;
877 error = vn_open(&nd, &flags, 0, NULL);
878 if (error)
879 return (error);
880
881 NDFREE(&nd, NDF_ONLY_PNBUF);
882 ofs = 0;
883 len = sizeof(buf) - 1;
884 while (1) {
885 error = vn_rdwr(UIO_READ, nd.ni_vp, buf, len, ofs,
886 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred,
887 NOCRED, &resid, td);
888 if (error)
889 break;
890 if (resid == len)
891 break;
892 buf[len - resid] = 0;
893 sbuf_printf(sb, "%s", buf);
894 ofs += len - resid;
895 }
896
897 VOP_UNLOCK(nd.ni_vp, 0);
898 vn_close(nd.ni_vp, FREAD, td->td_ucred, td);
899 return (error);
900 }
901
902 static void
903 vfs_mountroot_wait(void)
904 {
905 struct root_hold_token *h;
906 struct timeval lastfail;
907 int curfail;
908
909 curfail = 0;
910 while (1) {
911 DROP_GIANT();
912 g_waitidle();
913 PICKUP_GIANT();
914 mtx_lock(&root_holds_mtx);
915 if (LIST_EMPTY(&root_holds)) {
916 mtx_unlock(&root_holds_mtx);
917 break;
918 }
919 if (ppsratecheck(&lastfail, &curfail, 1)) {
920 printf("Root mount waiting for:");
921 LIST_FOREACH(h, &root_holds, list)
922 printf(" %s", h->who);
923 printf("\n");
924 }
925 msleep(&root_holds, &root_holds_mtx, PZERO | PDROP, "roothold",
926 hz);
927 }
928 }
929
930 void
931 vfs_mountroot(void)
932 {
933 struct mount *mp;
934 struct sbuf *sb;
935 struct thread *td;
936 time_t timebase;
937 int error;
938
939 td = curthread;
940
941 vfs_mountroot_wait();
942
943 sb = sbuf_new_auto();
944 vfs_mountroot_conf0(sb);
945 sbuf_finish(sb);
946
947 error = vfs_mountroot_devfs(td, &mp);
948 while (!error) {
949 error = vfs_mountroot_parse(sb, mp);
950 if (!error) {
951 error = vfs_mountroot_shuffle(td, mp);
952 if (!error) {
953 sbuf_clear(sb);
954 error = vfs_mountroot_readconf(td, sb);
955 sbuf_finish(sb);
956 }
957 }
958 }
959
960 sbuf_delete(sb);
961
962 /*
963 * Iterate over all currently mounted file systems and use
964 * the time stamp found to check and/or initialize the RTC.
965 * Call inittodr() only once and pass it the largest of the
966 * timestamps we encounter.
967 */
968 timebase = 0;
969 mtx_lock(&mountlist_mtx);
970 mp = TAILQ_FIRST(&mountlist);
971 while (mp != NULL) {
972 if (mp->mnt_time > timebase)
973 timebase = mp->mnt_time;
974 mp = TAILQ_NEXT(mp, mnt_list);
975 }
976 mtx_unlock(&mountlist_mtx);
977 inittodr(timebase);
978
979 /* Keep prison0's root in sync with the global rootvnode. */
980 mtx_lock(&prison0.pr_mtx);
981 prison0.pr_root = rootvnode;
982 vref(prison0.pr_root);
983 mtx_unlock(&prison0.pr_mtx);
984
985 mtx_lock(&root_holds_mtx);
986 atomic_store_rel_int(&root_mount_complete, 1);
987 wakeup(&root_mount_complete);
988 mtx_unlock(&root_holds_mtx);
989
990 EVENTHANDLER_INVOKE(mountroot);
991 }
992
993 static struct mntarg *
994 parse_mountroot_options(struct mntarg *ma, const char *options)
995 {
996 char *p;
997 char *name, *name_arg;
998 char *val, *val_arg;
999 char *opts;
1000
1001 if (options == NULL || options[0] == '\0')
1002 return (ma);
1003
1004 p = opts = strdup(options, M_MOUNT);
1005 if (opts == NULL) {
1006 return (ma);
1007 }
1008
1009 while((name = strsep(&p, ",")) != NULL) {
1010 if (name[0] == '\0')
1011 break;
1012
1013 val = strchr(name, '=');
1014 if (val != NULL) {
1015 *val = '\0';
1016 ++val;
1017 }
1018 if( strcmp(name, "rw") == 0 ||
1019 strcmp(name, "noro") == 0) {
1020 /*
1021 * The first time we mount the root file system,
1022 * we need to mount 'ro', so We need to ignore
1023 * 'rw' and 'noro' mount options.
1024 */
1025 continue;
1026 }
1027 name_arg = strdup(name, M_MOUNT);
1028 val_arg = NULL;
1029 if (val != NULL)
1030 val_arg = strdup(val, M_MOUNT);
1031
1032 ma = mount_arg(ma, name_arg, val_arg,
1033 (val_arg != NULL ? -1 : 0));
1034 }
1035 free(opts, M_MOUNT);
1036 return (ma);
1037 }
Cache object: 8d4cecec12dcfd2d986b4324d5caf8c6
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