1/*-
2 * Copyright (c) 1999-2004 Poul-Henning Kamp
3 * Copyright (c) 1999 Michael Smith
4 * Copyright (c) 1989, 1993
5 * The Regents of the University of California. All rights reserved.
6 * (c) UNIX System Laboratories, Inc.
7 * All or some portions of this file are derived from material licensed
8 * to the University of California by American Telephone and Telegraph
9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
10 * the permission of UNIX System Laboratories, Inc.
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 * notice, this list of conditions and the following disclaimer in the
19 * documentation and/or other materials provided with the distribution.
20 * 4. Neither the name of the University nor the names of its contributors
21 * may be used to endorse or promote products derived from this software
22 * without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 */
36
37#include <sys/cdefs.h>
38__FBSDID("$FreeBSD: head/sys/kern/vfs_mount.c 173064 2007-10-27 15:59:18Z rodrigc $");
39
40#include <sys/param.h>
41#include <sys/conf.h>
42#include <sys/clock.h>
43#include <sys/jail.h>
44#include <sys/kernel.h>
45#include <sys/libkern.h>
46#include <sys/malloc.h>
47#include <sys/mount.h>
48#include <sys/mutex.h>
49#include <sys/namei.h>
50#include <sys/priv.h>
51#include <sys/proc.h>
52#include <sys/filedesc.h>
53#include <sys/reboot.h>
54#include <sys/syscallsubr.h>
55#include <sys/sysproto.h>
56#include <sys/sx.h>
57#include <sys/sysctl.h>
58#include <sys/sysent.h>
59#include <sys/systm.h>
60#include <sys/vnode.h>
61#include <vm/uma.h>
62
63#include <geom/geom.h>
64
65#include <machine/stdarg.h>
66
67#include <security/audit/audit.h>
68#include <security/mac/mac_framework.h>
69
70#include "opt_rootdevname.h"
71#include "opt_ddb.h"
72#include "opt_mac.h"
73
74#ifdef DDB
75#include <ddb/ddb.h>
76#endif
77
78#define ROOTNAME "root_device"
79#define VFS_MOUNTARG_SIZE_MAX (1024 * 64)
80
81static int vfs_domount(struct thread *td, const char *fstype,
82 char *fspath, int fsflags, void *fsdata);
83static int vfs_mountroot_ask(void);
84static int vfs_mountroot_try(const char *mountfrom);
85static int vfs_donmount(struct thread *td, int fsflags,
86 struct uio *fsoptions);
87static void free_mntarg(struct mntarg *ma);
88static int vfs_getopt_pos(struct vfsoptlist *opts, const char *name);
89
90static int usermount = 0;
91SYSCTL_INT(_vfs, OID_AUTO, usermount, CTLFLAG_RW, &usermount, 0,
92 "Unprivileged users may mount and unmount file systems");
93
94MALLOC_DEFINE(M_MOUNT, "mount", "vfs mount structure");
95MALLOC_DEFINE(M_VNODE_MARKER, "vnodemarker", "vnode marker");
96static uma_zone_t mount_zone;
97
98/* List of mounted filesystems. */
99struct mntlist mountlist = TAILQ_HEAD_INITIALIZER(mountlist);
100
101/* For any iteration/modification of mountlist */
102struct mtx mountlist_mtx;
103MTX_SYSINIT(mountlist, &mountlist_mtx, "mountlist", MTX_DEF);
104
105TAILQ_HEAD(vfsoptlist, vfsopt);
106struct vfsopt {
107 TAILQ_ENTRY(vfsopt) link;
108 char *name;
109 void *value;
110 int len;
111};
112
113/*
114 * The vnode of the system's root (/ in the filesystem, without chroot
115 * active.)
116 */
117struct vnode *rootvnode;
118
119/*
120 * The root filesystem is detailed in the kernel environment variable
121 * vfs.root.mountfrom, which is expected to be in the general format
122 *
123 * <vfsname>:[<path>]
124 * vfsname := the name of a VFS known to the kernel and capable
125 * of being mounted as root
126 * path := disk device name or other data used by the filesystem
127 * to locate its physical store
128 */
129
130/*
131 * Global opts, taken by all filesystems
132 */
133static const char *global_opts[] = {
134 "errmsg",
135 "fstype",
136 "fspath",
137 "rdonly",
138 "ro",
139 "rw",
140 "nosuid",
141 "noexec",
142 "update",
143 NULL
144};
145
146/*
147 * The root specifiers we will try if RB_CDROM is specified.
148 */
149static char *cdrom_rootdevnames[] = {
150 "cd9660:cd0",
151 "cd9660:acd0",
152 NULL
153};
154
155/* legacy find-root code */
156char *rootdevnames[2] = {NULL, NULL};
157#ifndef ROOTDEVNAME
158# define ROOTDEVNAME NULL
159#endif
160static const char *ctrootdevname = ROOTDEVNAME;
161
162/*
163 * ---------------------------------------------------------------------
164 * Functions for building and sanitizing the mount options
165 */
166
167/* Remove one mount option. */
168static void
169vfs_freeopt(struct vfsoptlist *opts, struct vfsopt *opt)
170{
171
172 TAILQ_REMOVE(opts, opt, link);
173 free(opt->name, M_MOUNT);
174 if (opt->value != NULL)
175 free(opt->value, M_MOUNT);
176#ifdef INVARIANTS
177 else if (opt->len != 0)
178 panic("%s: mount option with NULL value but length != 0",
179 __func__);
180#endif
181 free(opt, M_MOUNT);
182}
183
184/* Release all resources related to the mount options. */
185void
186vfs_freeopts(struct vfsoptlist *opts)
187{
188 struct vfsopt *opt;
189
190 while (!TAILQ_EMPTY(opts)) {
191 opt = TAILQ_FIRST(opts);
192 vfs_freeopt(opts, opt);
193 }
194 free(opts, M_MOUNT);
195}
196
197void
198vfs_deleteopt(struct vfsoptlist *opts, const char *name)
199{
200 struct vfsopt *opt, *temp;
201
202 TAILQ_FOREACH_SAFE(opt, opts, link, temp) {
203 if (strcmp(opt->name, name) == 0)
204 vfs_freeopt(opts, opt);
205 }
206}
207
208/*
209 * Check if options are equal (with or without the "no" prefix).
210 */
211static int
212vfs_equalopts(const char *opt1, const char *opt2)
213{
214
215 /* "opt" vs. "opt" or "noopt" vs. "noopt" */
216 if (strcmp(opt1, opt2) == 0)
217 return (1);
218 /* "noopt" vs. "opt" */
219 if (strncmp(opt1, "no", 2) == 0 && strcmp(opt1 + 2, opt2) == 0)
220 return (1);
221 /* "opt" vs. "noopt" */
222 if (strncmp(opt2, "no", 2) == 0 && strcmp(opt1, opt2 + 2) == 0)
223 return (1);
224 return (0);
225}
226
227/*
228 * If a mount option is specified several times,
229 * (with or without the "no" prefix) only keep
230 * the last occurence of it.
231 */
232static void
233vfs_sanitizeopts(struct vfsoptlist *opts)
234{
235 struct vfsopt *opt, *opt2, *tmp;
236
237 TAILQ_FOREACH_REVERSE(opt, opts, vfsoptlist, link) {
238 opt2 = TAILQ_PREV(opt, vfsoptlist, link);
239 while (opt2 != NULL) {
240 if (vfs_equalopts(opt->name, opt2->name)) {
241 tmp = TAILQ_PREV(opt2, vfsoptlist, link);
242 vfs_freeopt(opts, opt2);
243 opt2 = tmp;
244 } else {
245 opt2 = TAILQ_PREV(opt2, vfsoptlist, link);
246 }
247 }
248 }
249}
250
251/*
252 * Build a linked list of mount options from a struct uio.
253 */
254static int
255vfs_buildopts(struct uio *auio, struct vfsoptlist **options)
256{
257 struct vfsoptlist *opts;
258 struct vfsopt *opt;
259 size_t memused;
260 unsigned int i, iovcnt;
261 int error, namelen, optlen;
262
263 opts = malloc(sizeof(struct vfsoptlist), M_MOUNT, M_WAITOK);
264 TAILQ_INIT(opts);
265 memused = 0;
266 iovcnt = auio->uio_iovcnt;
267 for (i = 0; i < iovcnt; i += 2) {
268 opt = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK);
269 namelen = auio->uio_iov[i].iov_len;
270 optlen = auio->uio_iov[i + 1].iov_len;
271 opt->name = malloc(namelen, M_MOUNT, M_WAITOK);
272 opt->value = NULL;
273 opt->len = 0;
274
275 /*
276 * Do this early, so jumps to "bad" will free the current
277 * option.
278 */
279 TAILQ_INSERT_TAIL(opts, opt, link);
280 memused += sizeof(struct vfsopt) + optlen + namelen;
281
282 /*
283 * Avoid consuming too much memory, and attempts to overflow
284 * memused.
285 */
286 if (memused > VFS_MOUNTARG_SIZE_MAX ||
287 optlen > VFS_MOUNTARG_SIZE_MAX ||
288 namelen > VFS_MOUNTARG_SIZE_MAX) {
289 error = EINVAL;
290 goto bad;
291 }
292
293 if (auio->uio_segflg == UIO_SYSSPACE) {
294 bcopy(auio->uio_iov[i].iov_base, opt->name, namelen);
295 } else {
296 error = copyin(auio->uio_iov[i].iov_base, opt->name,
297 namelen);
298 if (error)
299 goto bad;
300 }
301 /* Ensure names are null-terminated strings. */
302 if (opt->name[namelen - 1] != '\0') {
303 error = EINVAL;
304 goto bad;
305 }
306 if (optlen != 0) {
307 opt->len = optlen;
308 opt->value = malloc(optlen, M_MOUNT, M_WAITOK);
309 if (auio->uio_segflg == UIO_SYSSPACE) {
310 bcopy(auio->uio_iov[i + 1].iov_base, opt->value,
311 optlen);
312 } else {
313 error = copyin(auio->uio_iov[i + 1].iov_base,
314 opt->value, optlen);
315 if (error)
316 goto bad;
317 }
318 }
319 }
320 vfs_sanitizeopts(opts);
321 *options = opts;
322 return (0);
323bad:
324 vfs_freeopts(opts);
325 return (error);
326}
327
328/*
329 * Merge the old mount options with the new ones passed
330 * in the MNT_UPDATE case.
331 */
332static void
333vfs_mergeopts(struct vfsoptlist *toopts, struct vfsoptlist *opts)
334{
335 struct vfsopt *opt, *opt2, *new;
336
337 TAILQ_FOREACH(opt, opts, link) {
338 /*
339 * Check that this option hasn't been redefined
340 * nor cancelled with a "no" mount option.
341 */
342 opt2 = TAILQ_FIRST(toopts);
343 while (opt2 != NULL) {
344 if (strcmp(opt2->name, opt->name) == 0)
345 goto next;
346 if (strncmp(opt2->name, "no", 2) == 0 &&
347 strcmp(opt2->name + 2, opt->name) == 0) {
348 vfs_freeopt(toopts, opt2);
349 goto next;
350 }
351 opt2 = TAILQ_NEXT(opt2, link);
352 }
353 /* We want this option, duplicate it. */
354 new = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK);
355 new->name = malloc(strlen(opt->name) + 1, M_MOUNT, M_WAITOK);
356 strcpy(new->name, opt->name);
357 if (opt->len != 0) {
358 new->value = malloc(opt->len, M_MOUNT, M_WAITOK);
359 bcopy(opt->value, new->value, opt->len);
360 } else {
361 new->value = NULL;
362 }
363 new->len = opt->len;
364 TAILQ_INSERT_TAIL(toopts, new, link);
365next:
366 continue;
367 }
368}
369
370/*
371 * Mount a filesystem.
372 */
373int
374nmount(td, uap)
375 struct thread *td;
376 struct nmount_args /* {
377 struct iovec *iovp;
378 unsigned int iovcnt;
379 int flags;
380 } */ *uap;
381{
382 struct uio *auio;
383 struct iovec *iov;
384 unsigned int i;
385 int error;
386 u_int iovcnt;
387
388 AUDIT_ARG(fflags, uap->flags);
389
390 /*
391 * Filter out MNT_ROOTFS. We do not want clients of nmount() in
392 * userspace to set this flag, but we must filter it out if we want
393 * MNT_UPDATE on the root file system to work.
394 * MNT_ROOTFS should only be set in the kernel in vfs_mountroot_try().
395 */
396 uap->flags &= ~MNT_ROOTFS;
397
398 iovcnt = uap->iovcnt;
399 /*
400 * Check that we have an even number of iovec's
401 * and that we have at least two options.
402 */
403 if ((iovcnt & 1) || (iovcnt < 4))
404 return (EINVAL);
405
406 error = copyinuio(uap->iovp, iovcnt, &auio);
407 if (error)
408 return (error);
409 iov = auio->uio_iov;
410 for (i = 0; i < iovcnt; i++) {
411 if (iov->iov_len > MMAXOPTIONLEN) {
412 free(auio, M_IOV);
413 return (EINVAL);
414 }
415 iov++;
416 }
417 error = vfs_donmount(td, uap->flags, auio);
418
419 free(auio, M_IOV);
420 return (error);
421}
422
423/*
424 * ---------------------------------------------------------------------
425 * Various utility functions
426 */
427
428void
429vfs_ref(struct mount *mp)
430{
431
432 MNT_ILOCK(mp);
433 MNT_REF(mp);
434 MNT_IUNLOCK(mp);
435}
436
437void
438vfs_rel(struct mount *mp)
439{
440
441 MNT_ILOCK(mp);
442 MNT_REL(mp);
443 MNT_IUNLOCK(mp);
444}
445
446static int
447mount_init(void *mem, int size, int flags)
448{
449 struct mount *mp;
450
451 mp = (struct mount *)mem;
452 mtx_init(&mp->mnt_mtx, "struct mount mtx", NULL, MTX_DEF);
453 lockinit(&mp->mnt_lock, PVFS, "vfslock", 0, 0);
454 return (0);
455}
456
457static void
458mount_fini(void *mem, int size)
459{
460 struct mount *mp;
461
462 mp = (struct mount *)mem;
463 lockdestroy(&mp->mnt_lock);
464 mtx_destroy(&mp->mnt_mtx);
465}
466
467/*
468 * Allocate and initialize the mount point struct.
469 */
470struct mount *
471vfs_mount_alloc(struct vnode *vp, struct vfsconf *vfsp,
472 const char *fspath, struct thread *td)
473{
474 struct mount *mp;
475
476 mp = uma_zalloc(mount_zone, M_WAITOK);
477 bzero(&mp->mnt_startzero,
478 __rangeof(struct mount, mnt_startzero, mnt_endzero));
479 TAILQ_INIT(&mp->mnt_nvnodelist);
480 mp->mnt_nvnodelistsize = 0;
481 mp->mnt_ref = 0;
482 (void) vfs_busy(mp, LK_NOWAIT, 0, td);
483 mp->mnt_op = vfsp->vfc_vfsops;
484 mp->mnt_vfc = vfsp;
485 vfsp->vfc_refcount++; /* XXX Unlocked */
486 mp->mnt_stat.f_type = vfsp->vfc_typenum;
487 mp->mnt_gen++;
488 strlcpy(mp->mnt_stat.f_fstypename, vfsp->vfc_name, MFSNAMELEN);
489 mp->mnt_vnodecovered = vp;
490 mp->mnt_cred = crdup(td->td_ucred);
491 mp->mnt_stat.f_owner = td->td_ucred->cr_uid;
492 strlcpy(mp->mnt_stat.f_mntonname, fspath, MNAMELEN);
493 mp->mnt_iosize_max = DFLTPHYS;
494#ifdef MAC
495 mac_mount_init(mp);
496 mac_mount_create(td->td_ucred, mp);
497#endif
498 arc4rand(&mp->mnt_hashseed, sizeof mp->mnt_hashseed, 0);
499 return (mp);
500}
501
502/*
503 * Destroy the mount struct previously allocated by vfs_mount_alloc().
504 */
505void
506vfs_mount_destroy(struct mount *mp)
507{
508 int i;
509
510 MNT_ILOCK(mp);
511 for (i = 0; mp->mnt_ref && i < 3; i++)
512 msleep(mp, MNT_MTX(mp), PVFS, "mntref", hz);
513 /*
514 * This will always cause a 3 second delay in rebooting due to
515 * refs on the root mountpoint that never go away. Most of these
516 * are held by init which never exits.
517 */
518 if (i == 3 && (!rebooting || bootverbose))
519 printf("Mount point %s had %d dangling refs\n",
520 mp->mnt_stat.f_mntonname, mp->mnt_ref);
521 if (mp->mnt_holdcnt != 0) {
522 printf("Waiting for mount point to be unheld\n");
523 while (mp->mnt_holdcnt != 0) {
524 mp->mnt_holdcntwaiters++;
525 msleep(&mp->mnt_holdcnt, MNT_MTX(mp),
526 PZERO, "mntdestroy", 0);
527 mp->mnt_holdcntwaiters--;
528 }
529 printf("mount point unheld\n");
530 }
531 if (mp->mnt_writeopcount > 0) {
532 printf("Waiting for mount point write ops\n");
533 while (mp->mnt_writeopcount > 0) {
534 mp->mnt_kern_flag |= MNTK_SUSPEND;
535 msleep(&mp->mnt_writeopcount,
536 MNT_MTX(mp),
537 PZERO, "mntdestroy2", 0);
538 }
539 printf("mount point write ops completed\n");
540 }
541 if (mp->mnt_secondary_writes > 0) {
542 printf("Waiting for mount point secondary write ops\n");
543 while (mp->mnt_secondary_writes > 0) {
544 mp->mnt_kern_flag |= MNTK_SUSPEND;
545 msleep(&mp->mnt_secondary_writes,
546 MNT_MTX(mp),
547 PZERO, "mntdestroy3", 0);
548 }
549 printf("mount point secondary write ops completed\n");
550 }
551 MNT_IUNLOCK(mp);
552 mp->mnt_vfc->vfc_refcount--;
553 if (!TAILQ_EMPTY(&mp->mnt_nvnodelist)) {
554 struct vnode *vp;
555
556 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes)
557 vprint("", vp);
558 panic("unmount: dangling vnode");
559 }
560 MNT_ILOCK(mp);
561 if (mp->mnt_kern_flag & MNTK_MWAIT)
562 wakeup(mp);
563 if (mp->mnt_writeopcount != 0)
564 panic("vfs_mount_destroy: nonzero writeopcount");
565 if (mp->mnt_secondary_writes != 0)
566 panic("vfs_mount_destroy: nonzero secondary_writes");
567 if (mp->mnt_nvnodelistsize != 0)
568 panic("vfs_mount_destroy: nonzero nvnodelistsize");
569 mp->mnt_writeopcount = -1000;
570 mp->mnt_nvnodelistsize = -1000;
571 mp->mnt_secondary_writes = -1000;
572 MNT_IUNLOCK(mp);
573#ifdef MAC
574 mac_mount_destroy(mp);
575#endif
576 if (mp->mnt_opt != NULL)
577 vfs_freeopts(mp->mnt_opt);
578 crfree(mp->mnt_cred);
579 uma_zfree(mount_zone, mp);
580}
581
582static int
583vfs_donmount(struct thread *td, int fsflags, struct uio *fsoptions)
584{
585 struct vfsoptlist *optlist;
586 struct vfsopt *opt, *noro_opt;
587 char *fstype, *fspath, *errmsg;
588 int error, fstypelen, fspathlen, errmsg_len, errmsg_pos;
589 int has_rw, has_noro;
590
591 errmsg = NULL;
592 errmsg_len = 0;
593 errmsg_pos = -1;
594 has_rw = 0;
595 has_noro = 0;
596
597 error = vfs_buildopts(fsoptions, &optlist);
598 if (error)
599 return (error);
600
601 if (vfs_getopt(optlist, "errmsg", (void **)&errmsg, &errmsg_len) == 0)
602 errmsg_pos = vfs_getopt_pos(optlist, "errmsg");
603
604 /*
605 * We need these two options before the others,
606 * and they are mandatory for any filesystem.
607 * Ensure they are NUL terminated as well.
608 */
609 fstypelen = 0;
610 error = vfs_getopt(optlist, "fstype", (void **)&fstype, &fstypelen);
611 if (error || fstype[fstypelen - 1] != '\0') {
612 error = EINVAL;
613 if (errmsg != NULL)
614 strncpy(errmsg, "Invalid fstype", errmsg_len);
615 goto bail;
616 }
617 fspathlen = 0;
618 error = vfs_getopt(optlist, "fspath", (void **)&fspath, &fspathlen);
619 if (error || fspath[fspathlen - 1] != '\0') {
620 error = EINVAL;
621 if (errmsg != NULL)
622 strncpy(errmsg, "Invalid fspath", errmsg_len);
623 goto bail;
624 }
625
626 /*
627 * We need to see if we have the "update" option
628 * before we call vfs_domount(), since vfs_domount() has special
629 * logic based on MNT_UPDATE. This is very important
630 * when we want to update the root filesystem.
631 */
632 TAILQ_FOREACH(opt, optlist, link) {
633 if (strcmp(opt->name, "update") == 0)
634 fsflags |= MNT_UPDATE;
635 else if (strcmp(opt->name, "async") == 0)
636 fsflags |= MNT_ASYNC;
637 else if (strcmp(opt->name, "force") == 0)
638 fsflags |= MNT_FORCE;
639 else if (strcmp(opt->name, "multilabel") == 0)
640 fsflags |= MNT_MULTILABEL;
641 else if (strcmp(opt->name, "noasync") == 0)
642 fsflags &= ~MNT_ASYNC;
643 else if (strcmp(opt->name, "noatime") == 0)
644 fsflags |= MNT_NOATIME;
645 else if (strcmp(opt->name, "atime") == 0) {
646 free(opt->name, M_MOUNT);
647 opt->name = strdup("nonoatime", M_MOUNT);
648 }
649 else if (strcmp(opt->name, "noclusterr") == 0)
650 fsflags |= MNT_NOCLUSTERR;
651 else if (strcmp(opt->name, "clusterr") == 0) {
652 free(opt->name, M_MOUNT);
653 opt->name = strdup("nonoclusterr", M_MOUNT);
654 }
655 else if (strcmp(opt->name, "noclusterw") == 0)
656 fsflags |= MNT_NOCLUSTERW;
657 else if (strcmp(opt->name, "clusterw") == 0) {
658 free(opt->name, M_MOUNT);
659 opt->name = strdup("nonoclusterw", M_MOUNT);
660 }
661 else if (strcmp(opt->name, "noexec") == 0)
662 fsflags |= MNT_NOEXEC;
663 else if (strcmp(opt->name, "exec") == 0) {
664 free(opt->name, M_MOUNT);
665 opt->name = strdup("nonoexec", M_MOUNT);
666 }
667 else if (strcmp(opt->name, "nosuid") == 0)
668 fsflags |= MNT_NOSUID;
669 else if (strcmp(opt->name, "suid") == 0) {
670 free(opt->name, M_MOUNT);
671 opt->name = strdup("nonosuid", M_MOUNT);
672 }
673 else if (strcmp(opt->name, "nosymfollow") == 0)
674 fsflags |= MNT_NOSYMFOLLOW;
675 else if (strcmp(opt->name, "symfollow") == 0) {
676 free(opt->name, M_MOUNT);
677 opt->name = strdup("nonosymfollow", M_MOUNT);
678 }
679 else if (strcmp(opt->name, "noro") == 0) {
680 fsflags &= ~MNT_RDONLY;
681 has_noro = 1;
682 }
683 else if (strcmp(opt->name, "rw") == 0) {
684 fsflags &= ~MNT_RDONLY;
685 has_rw = 1;
686 }
687 else if (strcmp(opt->name, "ro") == 0 ||
688 strcmp(opt->name, "rdonly") == 0)
689 fsflags |= MNT_RDONLY;
690 else if (strcmp(opt->name, "snapshot") == 0)
691 fsflags |= MNT_SNAPSHOT;
692 else if (strcmp(opt->name, "suiddir") == 0)
693 fsflags |= MNT_SUIDDIR;
694 else if (strcmp(opt->name, "sync") == 0)
695 fsflags |= MNT_SYNCHRONOUS;
696 else if (strcmp(opt->name, "union") == 0)
697 fsflags |= MNT_UNION;
698 }
699
700 /*
701 * If "rw" was specified as a mount option, and we
702 * are trying to update a mount-point from "ro" to "rw",
703 * we need a mount option "noro", since in vfs_mergeopts(),
704 * "noro" will cancel "ro", but "rw" will not do anything.
705 */
706 if (has_rw && !has_noro) {
707 noro_opt = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK);
708 noro_opt->name = strdup("noro", M_MOUNT);
709 noro_opt->value = NULL;
710 noro_opt->len = 0;
711 TAILQ_INSERT_TAIL(optlist, noro_opt, link);
712 }
713
714 /*
715 * Be ultra-paranoid about making sure the type and fspath
716 * variables will fit in our mp buffers, including the
717 * terminating NUL.
718 */
719 if (fstypelen >= MFSNAMELEN - 1 || fspathlen >= MNAMELEN - 1) {
720 error = ENAMETOOLONG;
721 goto bail;
722 }
723
724 mtx_lock(&Giant);
725 error = vfs_domount(td, fstype, fspath, fsflags, optlist);
726 mtx_unlock(&Giant);
727bail:
728 /* copyout the errmsg */
729 if (errmsg_pos != -1 && ((2 * errmsg_pos + 1) < fsoptions->uio_iovcnt)
730 && errmsg_len > 0 && errmsg != NULL) {
731 if (fsoptions->uio_segflg == UIO_SYSSPACE) {
732 bcopy(errmsg,
733 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_base,
734 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_len);
735 } else {
736 copyout(errmsg,
737 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_base,
738 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_len);
739 }
740 }
741
742 if (error != 0)
743 vfs_freeopts(optlist);
744 return (error);
745}
746
747/*
748 * Old mount API.
749 */
750#ifndef _SYS_SYSPROTO_H_
751struct mount_args {
752 char *type;
753 char *path;
754 int flags;
755 caddr_t data;
756};
757#endif
758/* ARGSUSED */
759int
760mount(td, uap)
761 struct thread *td;
762 struct mount_args /* {
763 char *type;
764 char *path;
765 int flags;
766 caddr_t data;
767 } */ *uap;
768{
769 char *fstype;
770 struct vfsconf *vfsp = NULL;
771 struct mntarg *ma = NULL;
772 int error;
773
774 AUDIT_ARG(fflags, uap->flags);
775
776 /*
777 * Filter out MNT_ROOTFS. We do not want clients of mount() in
778 * userspace to set this flag, but we must filter it out if we want
779 * MNT_UPDATE on the root file system to work.
780 * MNT_ROOTFS should only be set in the kernel in vfs_mountroot_try().
781 */
782 uap->flags &= ~MNT_ROOTFS;
783
784 fstype = malloc(MFSNAMELEN, M_TEMP, M_WAITOK);
785 error = copyinstr(uap->type, fstype, MFSNAMELEN, NULL);
786 if (error) {
787 free(fstype, M_TEMP);
788 return (error);
789 }
790
791 AUDIT_ARG(text, fstype);
792 mtx_lock(&Giant);
793 vfsp = vfs_byname_kld(fstype, td, &error);
794 free(fstype, M_TEMP);
795 if (vfsp == NULL) {
796 mtx_unlock(&Giant);
797 return (ENOENT);
798 }
799 if (vfsp->vfc_vfsops->vfs_cmount == NULL) {
800 mtx_unlock(&Giant);
801 return (EOPNOTSUPP);
802 }
803
804 ma = mount_argsu(ma, "fstype", uap->type, MNAMELEN);
805 ma = mount_argsu(ma, "fspath", uap->path, MNAMELEN);
806 ma = mount_argb(ma, uap->flags & MNT_RDONLY, "noro");
807 ma = mount_argb(ma, !(uap->flags & MNT_NOSUID), "nosuid");
808 ma = mount_argb(ma, !(uap->flags & MNT_NOEXEC), "noexec");
809
810 error = vfsp->vfc_vfsops->vfs_cmount(ma, uap->data, uap->flags, td);
811 mtx_unlock(&Giant);
812 return (error);
813}
814
815
816/*
817 * vfs_domount(): actually attempt a filesystem mount.
818 */
819static int
820vfs_domount(
821 struct thread *td, /* Calling thread. */
822 const char *fstype, /* Filesystem type. */
823 char *fspath, /* Mount path. */
824 int fsflags, /* Flags common to all filesystems. */
825 void *fsdata /* Options local to the filesystem. */
826 )
827{
828 struct vnode *vp;
829 struct mount *mp;
830 struct vfsconf *vfsp;
831 struct export_args export;
832 int error, flag = 0;
833 struct vattr va;
834 struct nameidata nd;
835
836 mtx_assert(&Giant, MA_OWNED);
837 /*
838 * Be ultra-paranoid about making sure the type and fspath
839 * variables will fit in our mp buffers, including the
840 * terminating NUL.
841 */
842 if (strlen(fstype) >= MFSNAMELEN || strlen(fspath) >= MNAMELEN)
843 return (ENAMETOOLONG);
844
845 if (jailed(td->td_ucred) || usermount == 0) {
846 if ((error = priv_check(td, PRIV_VFS_MOUNT)) != 0)
847 return (error);
848 }
849
850 /*
851 * Do not allow NFS export or MNT_SUIDDIR by unprivileged users.
852 */
853 if (fsflags & MNT_EXPORTED) {
854 error = priv_check(td, PRIV_VFS_MOUNT_EXPORTED);
855 if (error)
856 return (error);
857 }
858 if (fsflags & MNT_SUIDDIR) {
859 error = priv_check(td, PRIV_VFS_MOUNT_SUIDDIR);
860 if (error)
861 return (error);
862 }
863 /*
864 * Silently enforce MNT_NOSUID and MNT_USER for unprivileged users.
865 */
866 if ((fsflags & (MNT_NOSUID | MNT_USER)) != (MNT_NOSUID | MNT_USER)) {
867 if (priv_check(td, PRIV_VFS_MOUNT_NONUSER) != 0)
868 fsflags |= MNT_NOSUID | MNT_USER;
869 }
870
871 /* Load KLDs before we lock the covered vnode to avoid reversals. */
872 vfsp = NULL;
873 if ((fsflags & MNT_UPDATE) == 0) {
874 /* Don't try to load KLDs if we're mounting the root. */
875 if (fsflags & MNT_ROOTFS)
876 vfsp = vfs_byname(fstype);
877 else
878 vfsp = vfs_byname_kld(fstype, td, &error);
879 if (vfsp == NULL)
880 return (ENODEV);
881 if (jailed(td->td_ucred) && !(vfsp->vfc_flags & VFCF_JAIL))
882 return (EPERM);
883 }
884 /*
885 * Get vnode to be covered
886 */
887 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | AUDITVNODE1, UIO_SYSSPACE,
888 fspath, td);
889 if ((error = namei(&nd)) != 0)
890 return (error);
891 NDFREE(&nd, NDF_ONLY_PNBUF);
892 vp = nd.ni_vp;
893 if (fsflags & MNT_UPDATE) {
894 if ((vp->v_vflag & VV_ROOT) == 0) {
895 vput(vp);
896 return (EINVAL);
897 }
898 mp = vp->v_mount;
899 MNT_ILOCK(mp);
900 flag = mp->mnt_flag;
901 /*
902 * We only allow the filesystem to be reloaded if it
903 * is currently mounted read-only.
904 */
905 if ((fsflags & MNT_RELOAD) &&
906 ((mp->mnt_flag & MNT_RDONLY) == 0)) {
907 MNT_IUNLOCK(mp);
908 vput(vp);
909 return (EOPNOTSUPP); /* Needs translation */
910 }
911 MNT_IUNLOCK(mp);
912 /*
913 * Only privileged root, or (if MNT_USER is set) the user that
914 * did the original mount is permitted to update it.
915 */
916 error = vfs_suser(mp, td);
917 if (error) {
918 vput(vp);
919 return (error);
920 }
921 if (vfs_busy(mp, LK_NOWAIT, 0, td)) {
922 vput(vp);
923 return (EBUSY);
924 }
925 VI_LOCK(vp);
926 if ((vp->v_iflag & VI_MOUNT) != 0 ||
927 vp->v_mountedhere != NULL) {
928 VI_UNLOCK(vp);
929 vfs_unbusy(mp, td);
930 vput(vp);
931 return (EBUSY);
932 }
933 vp->v_iflag |= VI_MOUNT;
934 VI_UNLOCK(vp);
935 MNT_ILOCK(mp);
936 mp->mnt_flag |= fsflags &
937 (MNT_RELOAD | MNT_FORCE | MNT_UPDATE | MNT_SNAPSHOT | MNT_ROOTFS);
938 MNT_IUNLOCK(mp);
939 VOP_UNLOCK(vp, 0, td);
940 mp->mnt_optnew = fsdata;
941 vfs_mergeopts(mp->mnt_optnew, mp->mnt_opt);
942 } else {
943 /*
944 * If the user is not root, ensure that they own the directory
945 * onto which we are attempting to mount.
946 */
947 error = VOP_GETATTR(vp, &va, td->td_ucred, td);
948 if (error) {
949 vput(vp);
950 return (error);
951 }
952 if (va.va_uid != td->td_ucred->cr_uid) {
953 error = priv_check_cred(td->td_ucred, PRIV_VFS_ADMIN,
954 0);
955 if (error) {
956 vput(vp);
957 return (error);
958 }
959 }
960 error = vinvalbuf(vp, V_SAVE, td, 0, 0);
961 if (error != 0) {
962 vput(vp);
963 return (error);
964 }
965 if (vp->v_type != VDIR) {
966 vput(vp);
967 return (ENOTDIR);
968 }
969 VI_LOCK(vp);
970 if ((vp->v_iflag & VI_MOUNT) != 0 ||
971 vp->v_mountedhere != NULL) {
972 VI_UNLOCK(vp);
973 vput(vp);
974 return (EBUSY);
975 }
976 vp->v_iflag |= VI_MOUNT;
977 VI_UNLOCK(vp);
978
979 /*
980 * Allocate and initialize the filesystem.
981 */
982 mp = vfs_mount_alloc(vp, vfsp, fspath, td);
983 VOP_UNLOCK(vp, 0, td);
984
985 /* XXXMAC: pass to vfs_mount_alloc? */
986 mp->mnt_optnew = fsdata;
987 }
988
989 /*
990 * Set the mount level flags.
991 */
992 MNT_ILOCK(mp);
993 mp->mnt_flag = (mp->mnt_flag & ~MNT_UPDATEMASK) |
994 (fsflags & (MNT_UPDATEMASK | MNT_FORCE | MNT_ROOTFS |
995 MNT_RDONLY));
996 if ((mp->mnt_flag & MNT_ASYNC) == 0)
997 mp->mnt_kern_flag &= ~MNTK_ASYNC;
998 MNT_IUNLOCK(mp);
999 /*
1000 * Mount the filesystem.
1001 * XXX The final recipients of VFS_MOUNT just overwrite the ndp they
1002 * get. No freeing of cn_pnbuf.
1003 */
1004 error = VFS_MOUNT(mp, td);
1005
1006 /*
1007 * Process the export option only if we are
1008 * updating mount options.
1009 */
1010 if (!error && (fsflags & MNT_UPDATE)) {
1011 if (vfs_copyopt(mp->mnt_optnew, "export", &export,
1012 sizeof(export)) == 0)
1013 error = vfs_export(mp, &export);
1014 }
1015
1016 if (!error) {
1017 if (mp->mnt_opt != NULL)
1018 vfs_freeopts(mp->mnt_opt);
1019 mp->mnt_opt = mp->mnt_optnew;
1020 (void)VFS_STATFS(mp, &mp->mnt_stat, td);
1021 }
1022 /*
1023 * Prevent external consumers of mount options from reading
1024 * mnt_optnew.
1025 */
1026 mp->mnt_optnew = NULL;
1027 if (mp->mnt_flag & MNT_UPDATE) {
1028 MNT_ILOCK(mp);
1029 if (error)
1030 mp->mnt_flag = (mp->mnt_flag & MNT_QUOTA) |
1031 (flag & ~MNT_QUOTA);
1032 else
1033 mp->mnt_flag &= ~(MNT_UPDATE | MNT_RELOAD |
1034 MNT_FORCE | MNT_SNAPSHOT);
1035 if ((mp->mnt_flag & MNT_ASYNC) != 0 && mp->mnt_noasync == 0)
1036 mp->mnt_kern_flag |= MNTK_ASYNC;
1037 else
1038 mp->mnt_kern_flag &= ~MNTK_ASYNC;
1039 MNT_IUNLOCK(mp);
1040 if ((mp->mnt_flag & MNT_RDONLY) == 0) {
1041 if (mp->mnt_syncer == NULL)
1042 error = vfs_allocate_syncvnode(mp);
1043 } else {
1044 if (mp->mnt_syncer != NULL)
1045 vrele(mp->mnt_syncer);
1046 mp->mnt_syncer = NULL;
1047 }
1048 vfs_unbusy(mp, td);
1049 VI_LOCK(vp);
1050 vp->v_iflag &= ~VI_MOUNT;
1051 VI_UNLOCK(vp);
1052 vrele(vp);
1053 return (error);
1054 }
1055 MNT_ILOCK(mp);
1056 if ((mp->mnt_flag & MNT_ASYNC) != 0 && mp->mnt_noasync == 0)
1057 mp->mnt_kern_flag |= MNTK_ASYNC;
1058 else
1059 mp->mnt_kern_flag &= ~MNTK_ASYNC;
1060 MNT_IUNLOCK(mp);
1061 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
1062 /*
1063 * Put the new filesystem on the mount list after root.
1064 */
1065 cache_purge(vp);
1066 if (!error) {
1067 struct vnode *newdp;
1068
1069 VI_LOCK(vp);
1070 vp->v_iflag &= ~VI_MOUNT;
1071 VI_UNLOCK(vp);
1072 vp->v_mountedhere = mp;
1073 mtx_lock(&mountlist_mtx);
1074 TAILQ_INSERT_TAIL(&mountlist, mp, mnt_list);
1075 mtx_unlock(&mountlist_mtx);
1076 vfs_event_signal(NULL, VQ_MOUNT, 0);
1077 if (VFS_ROOT(mp, LK_EXCLUSIVE, &newdp, td))
1078 panic("mount: lost mount");
1079 mountcheckdirs(vp, newdp);
1080 vput(newdp);
1081 VOP_UNLOCK(vp, 0, td);
1082 if ((mp->mnt_flag & MNT_RDONLY) == 0)
1083 error = vfs_allocate_syncvnode(mp);
1084 vfs_unbusy(mp, td);
1085 if (error)
1086 vrele(vp);
1087 } else {
1088 VI_LOCK(vp);
1089 vp->v_iflag &= ~VI_MOUNT;
1090 VI_UNLOCK(vp);
1091 vfs_unbusy(mp, td);
1092 vfs_mount_destroy(mp);
1093 vput(vp);
1094 }
1095 return (error);
1096}
1097
1098/*
1099 * Unmount a filesystem.
1100 *
1101 * Note: unmount takes a path to the vnode mounted on as argument, not
1102 * special file (as before).
1103 */
1104#ifndef _SYS_SYSPROTO_H_
1105struct unmount_args {
1106 char *path;
1107 int flags;
1108};
1109#endif
1110/* ARGSUSED */
1111int
1112unmount(td, uap)
1113 struct thread *td;
1114 register struct unmount_args /* {
1115 char *path;
1116 int flags;
1117 } */ *uap;
1118{
1119 struct mount *mp;
1120 char *pathbuf;
1121 int error, id0, id1;
1122
1123 if (jailed(td->td_ucred) || usermount == 0) {
1124 error = priv_check(td, PRIV_VFS_UNMOUNT);
1125 if (error)
1126 return (error);
1127 }
1128
1129 pathbuf = malloc(MNAMELEN, M_TEMP, M_WAITOK);
1130 error = copyinstr(uap->path, pathbuf, MNAMELEN, NULL);
1131 if (error) {
1132 free(pathbuf, M_TEMP);
1133 return (error);
1134 }
1135 AUDIT_ARG(upath, td, pathbuf, ARG_UPATH1);
1136 mtx_lock(&Giant);
1137 if (uap->flags & MNT_BYFSID) {
1138 /* Decode the filesystem ID. */
1139 if (sscanf(pathbuf, "FSID:%d:%d", &id0, &id1) != 2) {
1140 mtx_unlock(&Giant);
1141 free(pathbuf, M_TEMP);
1142 return (EINVAL);
1143 }
1144
1145 mtx_lock(&mountlist_mtx);
1146 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) {
1147 if (mp->mnt_stat.f_fsid.val[0] == id0 &&
1148 mp->mnt_stat.f_fsid.val[1] == id1)
1149 break;
1150 }
1151 mtx_unlock(&mountlist_mtx);
1152 } else {
1153 mtx_lock(&mountlist_mtx);
1154 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) {
1155 if (strcmp(mp->mnt_stat.f_mntonname, pathbuf) == 0)
1156 break;
1157 }
1158 mtx_unlock(&mountlist_mtx);
1159 }
1160 free(pathbuf, M_TEMP);
1161 if (mp == NULL) {
1162 /*
1163 * Previously we returned ENOENT for a nonexistent path and
1164 * EINVAL for a non-mountpoint. We cannot tell these apart
1165 * now, so in the !MNT_BYFSID case return the more likely
1166 * EINVAL for compatibility.
1167 */
1168 mtx_unlock(&Giant);
1169 return ((uap->flags & MNT_BYFSID) ? ENOENT : EINVAL);
1170 }
1171
1172 /*
1173 * Don't allow unmounting the root filesystem.
1174 */
1175 if (mp->mnt_flag & MNT_ROOTFS) {
1176 mtx_unlock(&Giant);
1177 return (EINVAL);
1178 }
1179 error = dounmount(mp, uap->flags, td);
1180 mtx_unlock(&Giant);
1181 return (error);
1182}
1183
1184/*
1185 * Do the actual filesystem unmount.
1186 */
1187int
1188dounmount(mp, flags, td)
1189 struct mount *mp;
1190 int flags;
1191 struct thread *td;
1192{
1193 struct vnode *coveredvp, *fsrootvp;
1194 int error;
1195 int async_flag;
1196 int mnt_gen_r;
1197
1198 mtx_assert(&Giant, MA_OWNED);
1199
1200 if ((coveredvp = mp->mnt_vnodecovered) != NULL) {
1201 mnt_gen_r = mp->mnt_gen;
1202 VI_LOCK(coveredvp);
1203 vholdl(coveredvp);
1204 vn_lock(coveredvp, LK_EXCLUSIVE | LK_INTERLOCK | LK_RETRY, td);
1205 vdrop(coveredvp);
1206 /*
1207 * Check for mp being unmounted while waiting for the
1208 * covered vnode lock.
1209 */
1210 if (coveredvp->v_mountedhere != mp ||
1211 coveredvp->v_mountedhere->mnt_gen != mnt_gen_r) {
1212 VOP_UNLOCK(coveredvp, 0, td);
1213 return (EBUSY);
1214 }
1215 }
1216 /*
1217 * Only privileged root, or (if MNT_USER is set) the user that did the
1218 * original mount is permitted to unmount this filesystem.
1219 */
1220 error = vfs_suser(mp, td);
1221 if (error) {
1222 if (coveredvp)
1223 VOP_UNLOCK(coveredvp, 0, td);
1224 return (error);
1225 }
1226
1227 MNT_ILOCK(mp);
1228 if (mp->mnt_kern_flag & MNTK_UNMOUNT) {
1229 MNT_IUNLOCK(mp);
1230 if (coveredvp)
1231 VOP_UNLOCK(coveredvp, 0, td);
1232 return (EBUSY);
1233 }
1234 mp->mnt_kern_flag |= MNTK_UNMOUNT | MNTK_NOINSMNTQ;
1235 /* Allow filesystems to detect that a forced unmount is in progress. */
1236 if (flags & MNT_FORCE)
1237 mp->mnt_kern_flag |= MNTK_UNMOUNTF;
1238 error = lockmgr(&mp->mnt_lock, LK_DRAIN | LK_INTERLOCK |
1239 ((flags & MNT_FORCE) ? 0 : LK_NOWAIT), MNT_MTX(mp), td);
1240 if (error) {
1241 MNT_ILOCK(mp);
1242 mp->mnt_kern_flag &= ~(MNTK_UNMOUNT | MNTK_NOINSMNTQ |
1243 MNTK_UNMOUNTF);
1244 if (mp->mnt_kern_flag & MNTK_MWAIT)
1245 wakeup(mp);
1246 MNT_IUNLOCK(mp);
1247 if (coveredvp)
1248 VOP_UNLOCK(coveredvp, 0, td);
1249 return (error);
1250 }
1251 vn_start_write(NULL, &mp, V_WAIT);
1252
1253 if (mp->mnt_flag & MNT_EXPUBLIC)
1254 vfs_setpublicfs(NULL, NULL, NULL);
1255
1256 vfs_msync(mp, MNT_WAIT);
1257 MNT_ILOCK(mp);
1258 async_flag = mp->mnt_flag & MNT_ASYNC;
1259 mp->mnt_flag &= ~MNT_ASYNC;
1260 mp->mnt_kern_flag &= ~MNTK_ASYNC;
1261 MNT_IUNLOCK(mp);
1262 cache_purgevfs(mp); /* remove cache entries for this file sys */
1263 if (mp->mnt_syncer != NULL)
1264 vrele(mp->mnt_syncer);
1265 /*
1266 * For forced unmounts, move process cdir/rdir refs on the fs root
1267 * vnode to the covered vnode. For non-forced unmounts we want
1268 * such references to cause an EBUSY error.
1269 */
1270 if ((flags & MNT_FORCE) &&
1271 VFS_ROOT(mp, LK_EXCLUSIVE, &fsrootvp, td) == 0) {
1272 if (mp->mnt_vnodecovered != NULL)
1273 mountcheckdirs(fsrootvp, mp->mnt_vnodecovered);
1274 if (fsrootvp == rootvnode) {
1275 vrele(rootvnode);
1276 rootvnode = NULL;
1277 }
1278 vput(fsrootvp);
1279 }
1280 if (((mp->mnt_flag & MNT_RDONLY) ||
1281 (error = VFS_SYNC(mp, MNT_WAIT, td)) == 0) ||
1282 (flags & MNT_FORCE)) {
1283 error = VFS_UNMOUNT(mp, flags, td);
1284 }
1285 vn_finished_write(mp);
1286 if (error) {
1287 /* Undo cdir/rdir and rootvnode changes made above. */
1288 if ((flags & MNT_FORCE) &&
1289 VFS_ROOT(mp, LK_EXCLUSIVE, &fsrootvp, td) == 0) {
1290 if (mp->mnt_vnodecovered != NULL)
1291 mountcheckdirs(mp->mnt_vnodecovered, fsrootvp);
1292 if (rootvnode == NULL) {
1293 rootvnode = fsrootvp;
1294 vref(rootvnode);
1295 }
1296 vput(fsrootvp);
1297 }
1298 MNT_ILOCK(mp);
1299 mp->mnt_kern_flag &= ~MNTK_NOINSMNTQ;
1300 if ((mp->mnt_flag & MNT_RDONLY) == 0 && mp->mnt_syncer == NULL) {
1301 MNT_IUNLOCK(mp);
1302 (void) vfs_allocate_syncvnode(mp);
1303 MNT_ILOCK(mp);
1304 }
1305 mp->mnt_kern_flag &= ~(MNTK_UNMOUNT | MNTK_UNMOUNTF);
1306 mp->mnt_flag |= async_flag;
1307 if ((mp->mnt_flag & MNT_ASYNC) != 0 && mp->mnt_noasync == 0)
1308 mp->mnt_kern_flag |= MNTK_ASYNC;
1309 lockmgr(&mp->mnt_lock, LK_RELEASE, NULL, td);
1310 if (mp->mnt_kern_flag & MNTK_MWAIT)
1311 wakeup(mp);
1312 MNT_IUNLOCK(mp);
1313 if (coveredvp)
1314 VOP_UNLOCK(coveredvp, 0, td);
1315 return (error);
1316 }
1317 mtx_lock(&mountlist_mtx);
1318 TAILQ_REMOVE(&mountlist, mp, mnt_list);
1319 mtx_unlock(&mountlist_mtx);
1320 if (coveredvp != NULL) {
1321 coveredvp->v_mountedhere = NULL;
1322 vput(coveredvp);
1323 }
1324 vfs_event_signal(NULL, VQ_UNMOUNT, 0);
1325 lockmgr(&mp->mnt_lock, LK_RELEASE, NULL, td);
1326 vfs_mount_destroy(mp);
1327 return (0);
1328}
1329
1330/*
1331 * ---------------------------------------------------------------------
1332 * Mounting of root filesystem
1333 *
1334 */
1335
1336struct root_hold_token {
1337 const char *who;
1338 LIST_ENTRY(root_hold_token) list;
1339};
1340
1341static LIST_HEAD(, root_hold_token) root_holds =
1342 LIST_HEAD_INITIALIZER(&root_holds);
1343
1344static int root_mount_complete;
1345
1346/*
1347 * Hold root mount.
1348 */
1349struct root_hold_token *
1350root_mount_hold(const char *identifier)
1351{
1352 struct root_hold_token *h;
1353
1354 h = malloc(sizeof *h, M_DEVBUF, M_ZERO | M_WAITOK);
1355 h->who = identifier;
1356 mtx_lock(&mountlist_mtx);
1357 LIST_INSERT_HEAD(&root_holds, h, list);
1358 mtx_unlock(&mountlist_mtx);
1359 return (h);
1360}
1361
1362/*
1363 * Release root mount.
1364 */
1365void
1366root_mount_rel(struct root_hold_token *h)
1367{
1368
1369 mtx_lock(&mountlist_mtx);
1370 LIST_REMOVE(h, list);
1371 wakeup(&root_holds);
1372 mtx_unlock(&mountlist_mtx);
1373 free(h, M_DEVBUF);
1374}
1375
1376/*
1377 * Wait for all subsystems to release root mount.
1378 */
1379static void
1380root_mount_prepare(void)
1381{
1382 struct root_hold_token *h;
1383
1384 for (;;) {
1385 DROP_GIANT();
1386 g_waitidle();
1387 PICKUP_GIANT();
1388 mtx_lock(&mountlist_mtx);
1389 if (LIST_EMPTY(&root_holds)) {
1390 mtx_unlock(&mountlist_mtx);
1391 break;
1392 }
1393 printf("Root mount waiting for:");
1394 LIST_FOREACH(h, &root_holds, list)
1395 printf(" %s", h->who);
1396 printf("\n");
1397 msleep(&root_holds, &mountlist_mtx, PZERO | PDROP, "roothold",
1398 hz);
1399 }
1400}
1401
1402/*
1403 * Root was mounted, share the good news.
1404 */
1405static void
1406root_mount_done(void)
1407{
1408
1409 /*
1410 * Use a mutex to prevent the wakeup being missed and waiting for
1411 * an extra 1 second sleep.
1412 */
1413 mtx_lock(&mountlist_mtx);
1414 root_mount_complete = 1;
1415 wakeup(&root_mount_complete);
1416 mtx_unlock(&mountlist_mtx);
1417}
1418
1419/*
1420 * Return true if root is already mounted.
1421 */
1422int
1423root_mounted(void)
1424{
1425
1426 /* No mutex is acquired here because int stores are atomic. */
1427 return (root_mount_complete);
1428}
1429
1430/*
1431 * Wait until root is mounted.
1432 */
1433void
1434root_mount_wait(void)
1435{
1436
1437 /*
1438 * Panic on an obvious deadlock - the function can't be called from
1439 * a thread which is doing the whole SYSINIT stuff.
1440 */
1441 KASSERT(curthread->td_proc->p_pid != 0,
1442 ("root_mount_wait: cannot be called from the swapper thread"));
1443 mtx_lock(&mountlist_mtx);
1444 while (!root_mount_complete) {
1445 msleep(&root_mount_complete, &mountlist_mtx, PZERO, "rootwait",
1446 hz);
1447 }
1448 mtx_unlock(&mountlist_mtx);
1449}
1450
1451static void
1452set_rootvnode(struct thread *td)
1453{
1454 struct proc *p;
1455
1456 if (VFS_ROOT(TAILQ_FIRST(&mountlist), LK_EXCLUSIVE, &rootvnode, td))
1457 panic("Cannot find root vnode");
1458
1459 p = td->td_proc;
1460 FILEDESC_SLOCK(p->p_fd);
1461
1462 if (p->p_fd->fd_cdir != NULL)
1463 vrele(p->p_fd->fd_cdir);
1464 p->p_fd->fd_cdir = rootvnode;
1465 VREF(rootvnode);
1466
1467 if (p->p_fd->fd_rdir != NULL)
1468 vrele(p->p_fd->fd_rdir);
1469 p->p_fd->fd_rdir = rootvnode;
1470 VREF(rootvnode);
1471
1472 FILEDESC_SUNLOCK(p->p_fd);
1473
1474 VOP_UNLOCK(rootvnode, 0, td);
1475}
1476
1477/*
1478 * Mount /devfs as our root filesystem, but do not put it on the mountlist
1479 * yet. Create a /dev -> / symlink so that absolute pathnames will lookup.
1480 */
1481
1482static void
1483devfs_first(void)
1484{
1485 struct thread *td = curthread;
1486 struct vfsoptlist *opts;
1487 struct vfsconf *vfsp;
1488 struct mount *mp = NULL;
1489 int error;
1490
1491 vfsp = vfs_byname("devfs");
1492 KASSERT(vfsp != NULL, ("Could not find devfs by name"));
1493 if (vfsp == NULL)
1494 return;
1495
1496 mp = vfs_mount_alloc(NULLVP, vfsp, "/dev", td);
1497
1498 error = VFS_MOUNT(mp, td);
1499 KASSERT(error == 0, ("VFS_MOUNT(devfs) failed %d", error));
1500 if (error)
1501 return;
1502
1503 opts = malloc(sizeof(struct vfsoptlist), M_MOUNT, M_WAITOK);
1504 TAILQ_INIT(opts);
1505 mp->mnt_opt = opts;
1506
1507 mtx_lock(&mountlist_mtx);
1508 TAILQ_INSERT_HEAD(&mountlist, mp, mnt_list);
1509 mtx_unlock(&mountlist_mtx);
1510
1511 set_rootvnode(td);
1512
1513 error = kern_symlink(td, "/", "dev", UIO_SYSSPACE);
1514 if (error)
1515 printf("kern_symlink /dev -> / returns %d\n", error);
1516}
1517
1518/*
1519 * Surgically move our devfs to be mounted on /dev.
1520 */
1521
1522static void
1523devfs_fixup(struct thread *td)
1524{
1525 struct nameidata nd;
1526 int error;
1527 struct vnode *vp, *dvp;
1528 struct mount *mp;
1529
1530 /* Remove our devfs mount from the mountlist and purge the cache */
1531 mtx_lock(&mountlist_mtx);
1532 mp = TAILQ_FIRST(&mountlist);
1533 TAILQ_REMOVE(&mountlist, mp, mnt_list);
1534 mtx_unlock(&mountlist_mtx);
1535 cache_purgevfs(mp);
1536
1537 VFS_ROOT(mp, LK_EXCLUSIVE, &dvp, td);
1538 VI_LOCK(dvp);
1539 dvp->v_iflag &= ~VI_MOUNT;
1540 VI_UNLOCK(dvp);
1541 dvp->v_mountedhere = NULL;
1542
1543 /* Set up the real rootvnode, and purge the cache */
1544 TAILQ_FIRST(&mountlist)->mnt_vnodecovered = NULL;
1545 set_rootvnode(td);
1546 cache_purgevfs(rootvnode->v_mount);
1547
1548 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, "/dev", td);
1549 error = namei(&nd);
1550 if (error) {
1551 printf("Lookup of /dev for devfs, error: %d\n", error);
1552 return;
1553 }
1554 NDFREE(&nd, NDF_ONLY_PNBUF);
1555 vp = nd.ni_vp;
1556 if (vp->v_type != VDIR) {
1557 vput(vp);
1558 }
1559 error = vinvalbuf(vp, V_SAVE, td, 0, 0);
1560 if (error) {
1561 vput(vp);
1562 }
1563 cache_purge(vp);
1564 mp->mnt_vnodecovered = vp;
1565 vp->v_mountedhere = mp;
1566 mtx_lock(&mountlist_mtx);
1567 TAILQ_INSERT_TAIL(&mountlist, mp, mnt_list);
1568 mtx_unlock(&mountlist_mtx);
1569 VOP_UNLOCK(vp, 0, td);
1570 vput(dvp);
1571 vfs_unbusy(mp, td);
1572
1573 /* Unlink the no longer needed /dev/dev -> / symlink */
1574 kern_unlink(td, "/dev/dev", UIO_SYSSPACE);
1575}
1576
1577/*
1578 * Report errors during filesystem mounting.
1579 */
1580void
1581vfs_mount_error(struct mount *mp, const char *fmt, ...)
1582{
1583 struct vfsoptlist *moptlist = mp->mnt_optnew;
1584 va_list ap;
1585 int error, len;
1586 char *errmsg;
1587
1588 error = vfs_getopt(moptlist, "errmsg", (void **)&errmsg, &len);
1589 if (error || errmsg == NULL || len <= 0)
1590 return;
1591
1592 va_start(ap, fmt);
1593 vsnprintf(errmsg, (size_t)len, fmt, ap);
1594 va_end(ap);
1595}
1596
1597/*
1598 * Find and mount the root filesystem
1599 */
1600void
1601vfs_mountroot(void)
1602{
1603 char *cp;
1604 int error, i, asked = 0;
1605
1606 root_mount_prepare();
1607
1608 mount_zone = uma_zcreate("Mountpoints", sizeof(struct mount),
1609 NULL, NULL, mount_init, mount_fini,
1610 UMA_ALIGN_PTR, UMA_ZONE_NOFREE);
1611 devfs_first();
1612
1613 /*
1614 * We are booted with instructions to prompt for the root filesystem.
1615 */
1616 if (boothowto & RB_ASKNAME) {
1617 if (!vfs_mountroot_ask())
1618 goto mounted;
1619 asked = 1;
1620 }
1621
1622 /*
1623 * The root filesystem information is compiled in, and we are
1624 * booted with instructions to use it.
1625 */
1626 if (ctrootdevname != NULL && (boothowto & RB_DFLTROOT)) {
1627 if (!vfs_mountroot_try(ctrootdevname))
1628 goto mounted;
1629 ctrootdevname = NULL;
1630 }
1631
1632 /*
1633 * We've been given the generic "use CDROM as root" flag. This is
1634 * necessary because one media may be used in many different
1635 * devices, so we need to search for them.
1636 */
1637 if (boothowto & RB_CDROM) {
1638 for (i = 0; cdrom_rootdevnames[i] != NULL; i++) {
1639 if (!vfs_mountroot_try(cdrom_rootdevnames[i]))
1640 goto mounted;
1641 }
1642 }
1643
1644 /*
1645 * Try to use the value read by the loader from /etc/fstab, or
1646 * supplied via some other means. This is the preferred
1647 * mechanism.
1648 */
1649 cp = getenv("vfs.root.mountfrom");
1650 if (cp != NULL) {
1651 error = vfs_mountroot_try(cp);
1652 freeenv(cp);
1653 if (!error)
1654 goto mounted;
1655 }
1656
1657 /*
1658 * Try values that may have been computed by code during boot
1659 */
1660 if (!vfs_mountroot_try(rootdevnames[0]))
1661 goto mounted;
1662 if (!vfs_mountroot_try(rootdevnames[1]))
1663 goto mounted;
1664
1665 /*
1666 * If we (still) have a compiled-in default, try it.
1667 */
1668 if (ctrootdevname != NULL)
1669 if (!vfs_mountroot_try(ctrootdevname))
1670 goto mounted;
1671 /*
1672 * Everything so far has failed, prompt on the console if we haven't
1673 * already tried that.
1674 */
1675 if (!asked)
1676 if (!vfs_mountroot_ask())
1677 goto mounted;
1678
1679 panic("Root mount failed, startup aborted.");
1680
1681mounted:
1682 root_mount_done();
1683}
1684
1685/*
1686 * Mount (mountfrom) as the root filesystem.
1687 */
1688static int
1689vfs_mountroot_try(const char *mountfrom)
1690{
1691 struct mount *mp;
1692 char *vfsname, *path;
1693 time_t timebase;
1694 int error;
1695 char patt[32];
1696
1697 vfsname = NULL;
1698 path = NULL;
1699 mp = NULL;
1700 error = EINVAL;
1701
1702 if (mountfrom == NULL)
1703 return (error); /* don't complain */
1704 printf("Trying to mount root from %s\n", mountfrom);
1705
1706 /* parse vfs name and path */
1707 vfsname = malloc(MFSNAMELEN, M_MOUNT, M_WAITOK);
1708 path = malloc(MNAMELEN, M_MOUNT, M_WAITOK);
1709 vfsname[0] = path[0] = 0;
1710 sprintf(patt, "%%%d[a-z0-9]:%%%ds", MFSNAMELEN, MNAMELEN);
1711 if (sscanf(mountfrom, patt, vfsname, path) < 1)
1712 goto out;
1713
1714 if (path[0] == '\0')
1715 strcpy(path, ROOTNAME);
1716
1717 error = kernel_vmount(
1718 MNT_RDONLY | MNT_ROOTFS,
1719 "fstype", vfsname,
1720 "fspath", "/",
1721 "from", path,
1722 NULL);
1723 if (error == 0) {
1724 /*
1725 * We mount devfs prior to mounting the / FS, so the first
1726 * entry will typically be devfs.
1727 */
1728 mp = TAILQ_FIRST(&mountlist);
1729 KASSERT(mp != NULL, ("%s: mountlist is empty", __func__));
1730
1731 /*
1732 * Iterate over all currently mounted file systems and use
1733 * the time stamp found to check and/or initialize the RTC.
1734 * Typically devfs has no time stamp and the only other FS
1735 * is the actual / FS.
1736 * Call inittodr() only once and pass it the largest of the
1737 * timestamps we encounter.
1738 */
1739 timebase = 0;
1740 do {
1741 if (mp->mnt_time > timebase)
1742 timebase = mp->mnt_time;
1743 mp = TAILQ_NEXT(mp, mnt_list);
1744 } while (mp != NULL);
1745 inittodr(timebase);
1746
1747 devfs_fixup(curthread);
1748 }
1749out:
1750 free(path, M_MOUNT);
1751 free(vfsname, M_MOUNT);
1752 return (error);
1753}
1754
1755/*
1756 * ---------------------------------------------------------------------
1757 * Interactive root filesystem selection code.
1758 */
1759
1760static int
1761vfs_mountroot_ask(void)
1762{
1763 char name[128];
1764
1765 for(;;) {
1766 printf("\nManual root filesystem specification:\n");
1767 printf(" <fstype>:<device> Mount <device> using filesystem <fstype>\n");
1768#if defined(__amd64__) || defined(__i386__) || defined(__ia64__)
1769 printf(" eg. ufs:da0s1a\n");
1770#else
1771 printf(" eg. ufs:/dev/da0a\n");
1772#endif
1773 printf(" ? List valid disk boot devices\n");
1774 printf(" <empty line> Abort manual input\n");
1775 printf("\nmountroot> ");
1776 gets(name, sizeof(name), 1);
1777 if (name[0] == '\0')
1778 return (1);
1779 if (name[0] == '?') {
1780 printf("\nList of GEOM managed disk devices:\n ");
1781 g_dev_print();
1782 continue;
1783 }
1784 if (!vfs_mountroot_try(name))
1785 return (0);
1786 }
1787}
1788
1789/*
1790 * ---------------------------------------------------------------------
1791 * Functions for querying mount options/arguments from filesystems.
1792 */
1793
1794/*
1795 * Check that no unknown options are given
1796 */
1797int
1798vfs_filteropt(struct vfsoptlist *opts, const char **legal)
1799{
1800 struct vfsopt *opt;
1801 char errmsg[255];
1802 const char **t, *p, *q;
1803 int ret = 0;
1804
1805 TAILQ_FOREACH(opt, opts, link) {
1806 p = opt->name;
1807 q = NULL;
1808 if (p[0] == 'n' && p[1] == 'o')
1809 q = p + 2;
1810 for(t = global_opts; *t != NULL; t++) {
1811 if (strcmp(*t, p) == 0)
1812 break;
1813 if (q != NULL) {
1814 if (strcmp(*t, q) == 0)
1815 break;
1816 }
1817 }
1818 if (*t != NULL)
1819 continue;
1820 for(t = legal; *t != NULL; t++) {
1821 if (strcmp(*t, p) == 0)
1822 break;
1823 if (q != NULL) {
1824 if (strcmp(*t, q) == 0)
1825 break;
1826 }
1827 }
1828 if (*t != NULL)
1829 continue;
1830 sprintf(errmsg, "mount option <%s> is unknown", p);
1831 printf("%s\n", errmsg);
1832 ret = EINVAL;
1833 }
1834 if (ret != 0) {
1835 TAILQ_FOREACH(opt, opts, link) {
1836 if (strcmp(opt->name, "errmsg") == 0) {
1837 strncpy((char *)opt->value, errmsg, opt->len);
1838 }
1839 }
1840 }
1841 return (ret);
1842}
1843
1844/*
1845 * Get a mount option by its name.
1846 *
1847 * Return 0 if the option was found, ENOENT otherwise.
1848 * If len is non-NULL it will be filled with the length
1849 * of the option. If buf is non-NULL, it will be filled
1850 * with the address of the option.
1851 */
1852int
1853vfs_getopt(opts, name, buf, len)
1854 struct vfsoptlist *opts;
1855 const char *name;
1856 void **buf;
1857 int *len;
1858{
1859 struct vfsopt *opt;
1860
1861 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL"));
1862
1863 TAILQ_FOREACH(opt, opts, link) {
1864 if (strcmp(name, opt->name) == 0) {
1865 if (len != NULL)
1866 *len = opt->len;
1867 if (buf != NULL)
1868 *buf = opt->value;
1869 return (0);
1870 }
1871 }
1872 return (ENOENT);
1873}
1874
1875static int
1876vfs_getopt_pos(struct vfsoptlist *opts, const char *name)
1877{
1878 struct vfsopt *opt;
1879 int i;
1880
1881 if (opts == NULL)
1882 return (-1);
1883
1884 i = 0;
1885 TAILQ_FOREACH(opt, opts, link) {
1886 if (strcmp(name, opt->name) == 0)
1887 return (i);
1888 ++i;
1889 }
1890 return (-1);
1891}
1892
1893char *
1894vfs_getopts(struct vfsoptlist *opts, const char *name, int *error)
1895{
1896 struct vfsopt *opt;
1897
1898 *error = 0;
1899 TAILQ_FOREACH(opt, opts, link) {
1900 if (strcmp(name, opt->name) != 0)
1901 continue;
1902 if (((char *)opt->value)[opt->len - 1] != '\0') {
1903 *error = EINVAL;
1904 return (NULL);
1905 }
1906 return (opt->value);
1907 }
1908 *error = ENOENT;
1909 return (NULL);
1910}
1911
1912int
1913vfs_flagopt(struct vfsoptlist *opts, const char *name, u_int *w, u_int val)
1914{
1915 struct vfsopt *opt;
1916
1917 TAILQ_FOREACH(opt, opts, link) {
1918 if (strcmp(name, opt->name) == 0) {
1919 if (w != NULL)
1920 *w |= val;
1921 return (1);
1922 }
1923 }
1924 if (w != NULL)
1925 *w &= ~val;
1926 return (0);
1927}
1928
1929int
1930vfs_scanopt(struct vfsoptlist *opts, const char *name, const char *fmt, ...)
1931{
1932 va_list ap;
1933 struct vfsopt *opt;
1934 int ret;
1935
1936 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL"));
1937
1938 TAILQ_FOREACH(opt, opts, link) {
1939 if (strcmp(name, opt->name) != 0)
1940 continue;
1941 if (((char *)opt->value)[opt->len - 1] != '\0')
1942 return (0);
1943 va_start(ap, fmt);
1944 ret = vsscanf(opt->value, fmt, ap);
1945 va_end(ap);
1946 return (ret);
1947 }
1948 return (0);
1949}
1950
1951/*
1952 * Find and copy a mount option.
1953 *
1954 * The size of the buffer has to be specified
1955 * in len, if it is not the same length as the
1956 * mount option, EINVAL is returned.
1957 * Returns ENOENT if the option is not found.
1958 */
1959int
1960vfs_copyopt(opts, name, dest, len)
1961 struct vfsoptlist *opts;
1962 const char *name;
1963 void *dest;
1964 int len;
1965{
1966 struct vfsopt *opt;
1967
1968 KASSERT(opts != NULL, ("vfs_copyopt: caller passed 'opts' as NULL"));
1969
1970 TAILQ_FOREACH(opt, opts, link) {
1971 if (strcmp(name, opt->name) == 0) {
1972 if (len != opt->len)
1973 return (EINVAL);
1974 bcopy(opt->value, dest, opt->len);
1975 return (0);
1976 }
1977 }
1978 return (ENOENT);
1979}
1980
1981/*
1982 * This is a helper function for filesystems to traverse their
1983 * vnodes. See MNT_VNODE_FOREACH() in sys/mount.h
1984 */
1985
1986struct vnode *
1987__mnt_vnode_next(struct vnode **mvp, struct mount *mp)
1988{
1989 struct vnode *vp;
1990
1991 mtx_assert(MNT_MTX(mp), MA_OWNED);
1992
1993 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch"));
1994 vp = TAILQ_NEXT(*mvp, v_nmntvnodes);
1995 while (vp != NULL && vp->v_type == VMARKER)
1996 vp = TAILQ_NEXT(vp, v_nmntvnodes);
1997
1998 /* Check if we are done */
1999 if (vp == NULL) {
2000 __mnt_vnode_markerfree(mvp, mp);
2001 return (NULL);
2002 }
2003 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes);
2004 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes);
2005 return (vp);
2006}
2007
2008struct vnode *
2009__mnt_vnode_first(struct vnode **mvp, struct mount *mp)
2010{
2011 struct vnode *vp;
2012
2013 mtx_assert(MNT_MTX(mp), MA_OWNED);
2014
2015 vp = TAILQ_FIRST(&mp->mnt_nvnodelist);
2016 while (vp != NULL && vp->v_type == VMARKER)
2017 vp = TAILQ_NEXT(vp, v_nmntvnodes);
2018
2019 /* Check if we are done */
2020 if (vp == NULL) {
2021 *mvp = NULL;
2022 return (NULL);
2023 }
2024 mp->mnt_holdcnt++;
2025 MNT_IUNLOCK(mp);
2026 *mvp = (struct vnode *) malloc(sizeof(struct vnode),
2027 M_VNODE_MARKER,
2028 M_WAITOK | M_ZERO);
2029 MNT_ILOCK(mp);
2030 (*mvp)->v_type = VMARKER;
2031
2032 vp = TAILQ_FIRST(&mp->mnt_nvnodelist);
2033 while (vp != NULL && vp->v_type == VMARKER)
2034 vp = TAILQ_NEXT(vp, v_nmntvnodes);
2035
2036 /* Check if we are done */
2037 if (vp == NULL) {
2038 MNT_IUNLOCK(mp);
2039 free(*mvp, M_VNODE_MARKER);
2040 MNT_ILOCK(mp);
2041 *mvp = NULL;
2042 mp->mnt_holdcnt--;
2043 if (mp->mnt_holdcnt == 0 && mp->mnt_holdcntwaiters != 0)
2044 wakeup(&mp->mnt_holdcnt);
2045 return (NULL);
2046 }
2047 mp->mnt_markercnt++;
2048 (*mvp)->v_mount = mp;
2049 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes);
2050 return (vp);
2051}
2052
2053
2054void
2055__mnt_vnode_markerfree(struct vnode **mvp, struct mount *mp)
2056{
2057
2058 if (*mvp == NULL)
2059 return;
2060
2061 mtx_assert(MNT_MTX(mp), MA_OWNED);
2062
2063 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch"));
2064 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes);
2065 MNT_IUNLOCK(mp);
2066 free(*mvp, M_VNODE_MARKER);
2067 MNT_ILOCK(mp);
2068 *mvp = NULL;
2069
2070 mp->mnt_markercnt--;
2071 mp->mnt_holdcnt--;
2072 if (mp->mnt_holdcnt == 0 && mp->mnt_holdcntwaiters != 0)
2073 wakeup(&mp->mnt_holdcnt);
2074}
2075
2076
2077int
2078__vfs_statfs(struct mount *mp, struct statfs *sbp, struct thread *td)
2079{
2080 int error;
2081
2082 error = mp->mnt_op->vfs_statfs(mp, &mp->mnt_stat, td);
2083 if (sbp != &mp->mnt_stat)
2084 *sbp = mp->mnt_stat;
2085 return (error);
2086}
2087
2088void
2089vfs_mountedfrom(struct mount *mp, const char *from)
2090{
2091
2092 bzero(mp->mnt_stat.f_mntfromname, sizeof mp->mnt_stat.f_mntfromname);
2093 strlcpy(mp->mnt_stat.f_mntfromname, from,
2094 sizeof mp->mnt_stat.f_mntfromname);
2095}
2096
2097/*
2098 * ---------------------------------------------------------------------
2099 * This is the api for building mount args and mounting filesystems from
2100 * inside the kernel.
2101 *
2102 * The API works by accumulation of individual args. First error is
2103 * latched.
2104 *
2105 * XXX: should be documented in new manpage kernel_mount(9)
2106 */
2107
2108/* A memory allocation which must be freed when we are done */
2109struct mntaarg {
2110 SLIST_ENTRY(mntaarg) next;
2111};
2112
2113/* The header for the mount arguments */
2114struct mntarg {
2115 struct iovec *v;
2116 int len;
2117 int error;
2118 SLIST_HEAD(, mntaarg) list;
2119};
2120
2121/*
2122 * Add a boolean argument.
2123 *
2124 * flag is the boolean value.
2125 * name must start with "no".
2126 */
2127struct mntarg *
2128mount_argb(struct mntarg *ma, int flag, const char *name)
2129{
2130
2131 KASSERT(name[0] == 'n' && name[1] == 'o',
2132 ("mount_argb(...,%s): name must start with 'no'", name));
2133
2134 return (mount_arg(ma, name + (flag ? 2 : 0), NULL, 0));
2135}
2136
2137/*
2138 * Add an argument printf style
2139 */
2140struct mntarg *
2141mount_argf(struct mntarg *ma, const char *name, const char *fmt, ...)
2142{
2143 va_list ap;
2144 struct mntaarg *maa;
2145 struct sbuf *sb;
2146 int len;
2147
2148 if (ma == NULL) {
2149 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO);
2150 SLIST_INIT(&ma->list);
2151 }
2152 if (ma->error)
2153 return (ma);
2154
2155 ma->v = realloc(ma->v, sizeof *ma->v * (ma->len + 2),
2156 M_MOUNT, M_WAITOK);
2157 ma->v[ma->len].iov_base = (void *)(uintptr_t)name;
2158 ma->v[ma->len].iov_len = strlen(name) + 1;
2159 ma->len++;
2160
2161 sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND);
2162 va_start(ap, fmt);
2163 sbuf_vprintf(sb, fmt, ap);
2164 va_end(ap);
2165 sbuf_finish(sb);
2166 len = sbuf_len(sb) + 1;
2167 maa = malloc(sizeof *maa + len, M_MOUNT, M_WAITOK | M_ZERO);
2168 SLIST_INSERT_HEAD(&ma->list, maa, next);
2169 bcopy(sbuf_data(sb), maa + 1, len);
2170 sbuf_delete(sb);
2171
2172 ma->v[ma->len].iov_base = maa + 1;
2173 ma->v[ma->len].iov_len = len;
2174 ma->len++;
2175
2176 return (ma);
2177}
2178
2179/*
2180 * Add an argument which is a userland string.
2181 */
2182struct mntarg *
2183mount_argsu(struct mntarg *ma, const char *name, const void *val, int len)
2184{
2185 struct mntaarg *maa;
2186 char *tbuf;
2187
2188 if (val == NULL)
2189 return (ma);
2190 if (ma == NULL) {
2191 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO);
2192 SLIST_INIT(&ma->list);
2193 }
2194 if (ma->error)
2195 return (ma);
2196 maa = malloc(sizeof *maa + len, M_MOUNT, M_WAITOK | M_ZERO);
2197 SLIST_INSERT_HEAD(&ma->list, maa, next);
2198 tbuf = (void *)(maa + 1);
2199 ma->error = copyinstr(val, tbuf, len, NULL);
2200 return (mount_arg(ma, name, tbuf, -1));
2201}
2202
2203/*
2204 * Plain argument.
2205 *
2206 * If length is -1, use printf.
2207 */
2208struct mntarg *
2209mount_arg(struct mntarg *ma, const char *name, const void *val, int len)
2210{
2211
2212 if (ma == NULL) {
2213 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO);
2214 SLIST_INIT(&ma->list);
2215 }
2216 if (ma->error)
2217 return (ma);
2218
2219 ma->v = realloc(ma->v, sizeof *ma->v * (ma->len + 2),
2220 M_MOUNT, M_WAITOK);
2221 ma->v[ma->len].iov_base = (void *)(uintptr_t)name;
2222 ma->v[ma->len].iov_len = strlen(name) + 1;
2223 ma->len++;
2224
2225 ma->v[ma->len].iov_base = (void *)(uintptr_t)val;
2226 if (len < 0)
2227 ma->v[ma->len].iov_len = strlen(val) + 1;
2228 else
2229 ma->v[ma->len].iov_len = len;
2230 ma->len++;
2231 return (ma);
2232}
2233
2234/*
2235 * Free a mntarg structure
2236 */
2237static void
2238free_mntarg(struct mntarg *ma)
2239{
2240 struct mntaarg *maa;
2241
2242 while (!SLIST_EMPTY(&ma->list)) {
2243 maa = SLIST_FIRST(&ma->list);
2244 SLIST_REMOVE_HEAD(&ma->list, next);
2245 free(maa, M_MOUNT);
2246 }
2247 free(ma->v, M_MOUNT);
2248 free(ma, M_MOUNT);
2249}
2250
2251/*
2252 * Mount a filesystem
2253 */
2254int
2255kernel_mount(struct mntarg *ma, int flags)
2256{
2257 struct uio auio;
2258 int error;
2259
2260 KASSERT(ma != NULL, ("kernel_mount NULL ma"));
2261 KASSERT(ma->v != NULL, ("kernel_mount NULL ma->v"));
2262 KASSERT(!(ma->len & 1), ("kernel_mount odd ma->len (%d)", ma->len));
2263
2264 auio.uio_iov = ma->v;
2265 auio.uio_iovcnt = ma->len;
2266 auio.uio_segflg = UIO_SYSSPACE;
2267
2268 error = ma->error;
2269 if (!error)
2270 error = vfs_donmount(curthread, flags, &auio);
2271 free_mntarg(ma);
2272 return (error);
2273}
2274
2275/*
2276 * A printflike function to mount a filesystem.
2277 */
2278int
2279kernel_vmount(int flags, ...)
2280{
2281 struct mntarg *ma = NULL;
2282 va_list ap;
2283 const char *cp;
2284 const void *vp;
2285 int error;
2286
2287 va_start(ap, flags);
2288 for (;;) {
2289 cp = va_arg(ap, const char *);
2290 if (cp == NULL)
2291 break;
2292 vp = va_arg(ap, const void *);
2293 ma = mount_arg(ma, cp, vp, -1);
2294 }
2295 va_end(ap);
2296
2297 error = kernel_mount(ma, flags);
2298 return (error);
2299}