1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22 /*
23 * Copyright 2015 Nexenta Systems, Inc. All rights reserved.
24 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
25 * Copyright (c) 2014, 2017 by Delphix. All rights reserved.
26 * Copyright 2016 Igor Kozhukhov <ikozhukhov@gmail.com>
27 * Copyright 2017 Joyent, Inc.
28 * Copyright 2017 RackTop Systems.
29 * Copyright 2018 OmniOS Community Edition (OmniOSce) Association.
30 */
31
32 /*
33 * Routines to manage ZFS mounts. We separate all the nasty routines that have
34 * to deal with the OS. The following functions are the main entry points --
35 * they are used by mount and unmount and when changing a filesystem's
36 * mountpoint.
37 *
38 * zfs_is_mounted()
39 * zfs_mount()
40 * zfs_unmount()
41 * zfs_unmountall()
42 *
43 * This file also contains the functions used to manage sharing filesystems via
44 * NFS and iSCSI:
45 *
46 * zfs_is_shared()
47 * zfs_share()
48 * zfs_unshare()
49 *
50 * zfs_is_shared_nfs()
51 * zfs_is_shared_smb()
52 * zfs_share_proto()
53 * zfs_shareall();
54 * zfs_unshare_nfs()
55 * zfs_unshare_smb()
56 * zfs_unshareall_nfs()
57 * zfs_unshareall_smb()
58 * zfs_unshareall()
59 * zfs_unshareall_bypath()
60 *
61 * The following functions are available for pool consumers, and will
62 * mount/unmount and share/unshare all datasets within pool:
63 *
64 * zpool_enable_datasets()
65 * zpool_disable_datasets()
66 */
67
68 #include <dirent.h>
69 #include <dlfcn.h>
70 #include <errno.h>
71 #include <fcntl.h>
72 #include <libgen.h>
73 #include <libintl.h>
74 #include <stdio.h>
75 #include <stdlib.h>
76 #include <strings.h>
77 #include <unistd.h>
78 #include <zone.h>
79 #include <sys/mntent.h>
80 #include <sys/mount.h>
81 #include <sys/stat.h>
82 #include <sys/statvfs.h>
83 #include <sys/dsl_crypt.h>
84
85 #include <libzfs.h>
86
87 #include "libzfs_impl.h"
88 #include "libzfs_taskq.h"
89
90 #include <libshare.h>
91 #include <sys/systeminfo.h>
92 #define MAXISALEN 257 /* based on sysinfo(2) man page */
93
94 static int mount_tq_nthr = 512; /* taskq threads for multi-threaded mounting */
95
96 static void zfs_mount_task(void *);
97 static int zfs_share_proto(zfs_handle_t *, zfs_share_proto_t *);
98 zfs_share_type_t zfs_is_shared_proto(zfs_handle_t *, char **,
99 zfs_share_proto_t);
100
101 /*
102 * The share protocols table must be in the same order as the zfs_share_proto_t
103 * enum in libzfs_impl.h
104 */
105 typedef struct {
106 zfs_prop_t p_prop;
107 char *p_name;
108 int p_share_err;
109 int p_unshare_err;
110 } proto_table_t;
111
112 proto_table_t proto_table[PROTO_END] = {
113 {ZFS_PROP_SHARENFS, "nfs", EZFS_SHARENFSFAILED, EZFS_UNSHARENFSFAILED},
114 {ZFS_PROP_SHARESMB, "smb", EZFS_SHARESMBFAILED, EZFS_UNSHARESMBFAILED},
115 };
116
117 zfs_share_proto_t nfs_only[] = {
118 PROTO_NFS,
119 PROTO_END
120 };
121
122 zfs_share_proto_t smb_only[] = {
123 PROTO_SMB,
124 PROTO_END
125 };
126 zfs_share_proto_t share_all_proto[] = {
127 PROTO_NFS,
128 PROTO_SMB,
129 PROTO_END
130 };
131
132 /*
133 * Search the sharetab for the given mountpoint and protocol, returning
134 * a zfs_share_type_t value.
135 */
136 static zfs_share_type_t
137 is_shared(libzfs_handle_t *hdl, const char *mountpoint, zfs_share_proto_t proto)
138 {
139 char buf[MAXPATHLEN], *tab;
140 char *ptr;
141
142 if (hdl->libzfs_sharetab == NULL)
143 return (SHARED_NOT_SHARED);
144
145 (void) fseek(hdl->libzfs_sharetab, 0, SEEK_SET);
146
147 while (fgets(buf, sizeof (buf), hdl->libzfs_sharetab) != NULL) {
148
149 /* the mountpoint is the first entry on each line */
150 if ((tab = strchr(buf, '\t')) == NULL)
151 continue;
152
153 *tab = '\0';
154 if (strcmp(buf, mountpoint) == 0) {
155 /*
156 * the protocol field is the third field
157 * skip over second field
158 */
159 ptr = ++tab;
160 if ((tab = strchr(ptr, '\t')) == NULL)
161 continue;
162 ptr = ++tab;
163 if ((tab = strchr(ptr, '\t')) == NULL)
164 continue;
165 *tab = '\0';
166 if (strcmp(ptr,
167 proto_table[proto].p_name) == 0) {
168 switch (proto) {
169 case PROTO_NFS:
170 return (SHARED_NFS);
171 case PROTO_SMB:
172 return (SHARED_SMB);
173 default:
174 return (0);
175 }
176 }
177 }
178 }
179
180 return (SHARED_NOT_SHARED);
181 }
182
183 static boolean_t
184 dir_is_empty_stat(const char *dirname)
185 {
186 struct stat st;
187
188 /*
189 * We only want to return false if the given path is a non empty
190 * directory, all other errors are handled elsewhere.
191 */
192 if (stat(dirname, &st) < 0 || !S_ISDIR(st.st_mode)) {
193 return (B_TRUE);
194 }
195
196 /*
197 * An empty directory will still have two entries in it, one
198 * entry for each of "." and "..".
199 */
200 if (st.st_size > 2) {
201 return (B_FALSE);
202 }
203
204 return (B_TRUE);
205 }
206
207 static boolean_t
208 dir_is_empty_readdir(const char *dirname)
209 {
210 DIR *dirp;
211 struct dirent64 *dp;
212 int dirfd;
213
214 if ((dirfd = openat(AT_FDCWD, dirname,
215 O_RDONLY | O_NDELAY | O_LARGEFILE | O_CLOEXEC, 0)) < 0) {
216 return (B_TRUE);
217 }
218
219 if ((dirp = fdopendir(dirfd)) == NULL) {
220 (void) close(dirfd);
221 return (B_TRUE);
222 }
223
224 while ((dp = readdir64(dirp)) != NULL) {
225
226 if (strcmp(dp->d_name, ".") == 0 ||
227 strcmp(dp->d_name, "..") == 0)
228 continue;
229
230 (void) closedir(dirp);
231 return (B_FALSE);
232 }
233
234 (void) closedir(dirp);
235 return (B_TRUE);
236 }
237
238 /*
239 * Returns true if the specified directory is empty. If we can't open the
240 * directory at all, return true so that the mount can fail with a more
241 * informative error message.
242 */
243 static boolean_t
244 dir_is_empty(const char *dirname)
245 {
246 struct statvfs64 st;
247
248 /*
249 * If the statvfs call fails or the filesystem is not a ZFS
250 * filesystem, fall back to the slow path which uses readdir.
251 */
252 if ((statvfs64(dirname, &st) != 0) ||
253 (strcmp(st.f_basetype, "zfs") != 0)) {
254 return (dir_is_empty_readdir(dirname));
255 }
256
257 /*
258 * At this point, we know the provided path is on a ZFS
259 * filesystem, so we can use stat instead of readdir to
260 * determine if the directory is empty or not. We try to avoid
261 * using readdir because that requires opening "dirname"; this
262 * open file descriptor can potentially end up in a child
263 * process if there's a concurrent fork, thus preventing the
264 * zfs_mount() from otherwise succeeding (the open file
265 * descriptor inherited by the child process will cause the
266 * parent's mount to fail with EBUSY). The performance
267 * implications of replacing the open, read, and close with a
268 * single stat is nice; but is not the main motivation for the
269 * added complexity.
270 */
271 return (dir_is_empty_stat(dirname));
272 }
273
274 /*
275 * Checks to see if the mount is active. If the filesystem is mounted, we fill
276 * in 'where' with the current mountpoint, and return 1. Otherwise, we return
277 * 0.
278 */
279 boolean_t
280 is_mounted(libzfs_handle_t *zfs_hdl, const char *special, char **where)
281 {
282 struct mnttab entry;
283
284 if (libzfs_mnttab_find(zfs_hdl, special, &entry) != 0)
285 return (B_FALSE);
286
287 if (where != NULL)
288 *where = zfs_strdup(zfs_hdl, entry.mnt_mountp);
289
290 return (B_TRUE);
291 }
292
293 boolean_t
294 zfs_is_mounted(zfs_handle_t *zhp, char **where)
295 {
296 return (is_mounted(zhp->zfs_hdl, zfs_get_name(zhp), where));
297 }
298
299 /*
300 * Returns true if the given dataset is mountable, false otherwise. Returns the
301 * mountpoint in 'buf'.
302 */
303 static boolean_t
304 zfs_is_mountable(zfs_handle_t *zhp, char *buf, size_t buflen,
305 zprop_source_t *source)
306 {
307 char sourceloc[MAXNAMELEN];
308 zprop_source_t sourcetype;
309
310 if (!zfs_prop_valid_for_type(ZFS_PROP_MOUNTPOINT, zhp->zfs_type))
311 return (B_FALSE);
312
313 verify(zfs_prop_get(zhp, ZFS_PROP_MOUNTPOINT, buf, buflen,
314 &sourcetype, sourceloc, sizeof (sourceloc), B_FALSE) == 0);
315
316 if (strcmp(buf, ZFS_MOUNTPOINT_NONE) == 0 ||
317 strcmp(buf, ZFS_MOUNTPOINT_LEGACY) == 0)
318 return (B_FALSE);
319
320 if (zfs_prop_get_int(zhp, ZFS_PROP_CANMOUNT) == ZFS_CANMOUNT_OFF)
321 return (B_FALSE);
322
323 if (zfs_prop_get_int(zhp, ZFS_PROP_ZONED) &&
324 getzoneid() == GLOBAL_ZONEID)
325 return (B_FALSE);
326
327 if (source)
328 *source = sourcetype;
329
330 return (B_TRUE);
331 }
332
333 /*
334 * Mount the given filesystem.
335 */
336 int
337 zfs_mount(zfs_handle_t *zhp, const char *options, int flags)
338 {
339 struct stat buf;
340 char mountpoint[ZFS_MAXPROPLEN];
341 char mntopts[MNT_LINE_MAX];
342 libzfs_handle_t *hdl = zhp->zfs_hdl;
343 uint64_t keystatus;
344 int rc;
345
346 if (options == NULL)
347 mntopts[0] = '\0';
348 else
349 (void) strlcpy(mntopts, options, sizeof (mntopts));
350
351 /*
352 * If the pool is imported read-only then all mounts must be read-only
353 */
354 if (zpool_get_prop_int(zhp->zpool_hdl, ZPOOL_PROP_READONLY, NULL))
355 flags |= MS_RDONLY;
356
357 if (!zfs_is_mountable(zhp, mountpoint, sizeof (mountpoint), NULL))
358 return (0);
359
360 /*
361 * If the filesystem is encrypted the key must be loaded in order to
362 * mount. If the key isn't loaded, the MS_CRYPT flag decides whether
363 * or not we attempt to load the keys. Note: we must call
364 * zfs_refresh_properties() here since some callers of this function
365 * (most notably zpool_enable_datasets()) may implicitly load our key
366 * by loading the parent's key first.
367 */
368 if (zfs_prop_get_int(zhp, ZFS_PROP_ENCRYPTION) != ZIO_CRYPT_OFF) {
369 zfs_refresh_properties(zhp);
370 keystatus = zfs_prop_get_int(zhp, ZFS_PROP_KEYSTATUS);
371
372 /*
373 * If the key is unavailable and MS_CRYPT is set give the
374 * user a chance to enter the key. Otherwise just fail
375 * immediately.
376 */
377 if (keystatus == ZFS_KEYSTATUS_UNAVAILABLE) {
378 if (flags & MS_CRYPT) {
379 rc = zfs_crypto_load_key(zhp, B_FALSE, NULL);
380 if (rc != 0)
381 return (rc);
382 } else {
383 zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
384 "encryption key not loaded"));
385 return (zfs_error_fmt(hdl, EZFS_MOUNTFAILED,
386 dgettext(TEXT_DOMAIN, "cannot mount '%s'"),
387 mountpoint));
388 }
389 }
390
391 }
392
393 /* Create the directory if it doesn't already exist */
394 if (lstat(mountpoint, &buf) != 0) {
395 if (mkdirp(mountpoint, 0755) != 0) {
396 zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
397 "failed to create mountpoint"));
398 return (zfs_error_fmt(hdl, EZFS_MOUNTFAILED,
399 dgettext(TEXT_DOMAIN, "cannot mount '%s'"),
400 mountpoint));
401 }
402 }
403
404 /*
405 * Determine if the mountpoint is empty. If so, refuse to perform the
406 * mount. We don't perform this check if MS_OVERLAY is specified, which
407 * would defeat the point. We also avoid this check if 'remount' is
408 * specified.
409 */
410 if ((flags & MS_OVERLAY) == 0 &&
411 strstr(mntopts, MNTOPT_REMOUNT) == NULL &&
412 !dir_is_empty(mountpoint)) {
413 zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
414 "directory is not empty"));
415 return (zfs_error_fmt(hdl, EZFS_MOUNTFAILED,
416 dgettext(TEXT_DOMAIN, "cannot mount '%s'"), mountpoint));
417 }
418
419 /* perform the mount */
420 if (mount(zfs_get_name(zhp), mountpoint, MS_OPTIONSTR | flags,
421 MNTTYPE_ZFS, NULL, 0, mntopts, sizeof (mntopts)) != 0) {
422 /*
423 * Generic errors are nasty, but there are just way too many
424 * from mount(), and they're well-understood. We pick a few
425 * common ones to improve upon.
426 */
427 if (errno == EBUSY) {
428 zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
429 "mountpoint or dataset is busy"));
430 } else if (errno == EPERM) {
431 zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
432 "Insufficient privileges"));
433 } else if (errno == ENOTSUP) {
434 char buf[256];
435 int spa_version;
436
437 VERIFY(zfs_spa_version(zhp, &spa_version) == 0);
438 (void) snprintf(buf, sizeof (buf),
439 dgettext(TEXT_DOMAIN, "Can't mount a version %lld "
440 "file system on a version %d pool. Pool must be"
441 " upgraded to mount this file system."),
442 (u_longlong_t)zfs_prop_get_int(zhp,
443 ZFS_PROP_VERSION), spa_version);
444 zfs_error_aux(hdl, dgettext(TEXT_DOMAIN, buf));
445 } else {
446 zfs_error_aux(hdl, strerror(errno));
447 }
448 return (zfs_error_fmt(hdl, EZFS_MOUNTFAILED,
449 dgettext(TEXT_DOMAIN, "cannot mount '%s'"),
450 zhp->zfs_name));
451 }
452
453 /* add the mounted entry into our cache */
454 libzfs_mnttab_add(hdl, zfs_get_name(zhp), mountpoint,
455 mntopts);
456 return (0);
457 }
458
459 /*
460 * Unmount a single filesystem.
461 */
462 static int
463 unmount_one(libzfs_handle_t *hdl, const char *mountpoint, int flags)
464 {
465 if (umount2(mountpoint, flags) != 0) {
466 zfs_error_aux(hdl, strerror(errno));
467 return (zfs_error_fmt(hdl, EZFS_UMOUNTFAILED,
468 dgettext(TEXT_DOMAIN, "cannot unmount '%s'"),
469 mountpoint));
470 }
471
472 return (0);
473 }
474
475 /*
476 * Unmount the given filesystem.
477 */
478 int
479 zfs_unmount(zfs_handle_t *zhp, const char *mountpoint, int flags)
480 {
481 libzfs_handle_t *hdl = zhp->zfs_hdl;
482 struct mnttab entry;
483 char *mntpt = NULL;
484
485 /* check to see if we need to unmount the filesystem */
486 if (mountpoint != NULL || ((zfs_get_type(zhp) == ZFS_TYPE_FILESYSTEM) &&
487 libzfs_mnttab_find(hdl, zhp->zfs_name, &entry) == 0)) {
488 /*
489 * mountpoint may have come from a call to
490 * getmnt/getmntany if it isn't NULL. If it is NULL,
491 * we know it comes from libzfs_mnttab_find which can
492 * then get freed later. We strdup it to play it safe.
493 */
494 if (mountpoint == NULL)
495 mntpt = zfs_strdup(hdl, entry.mnt_mountp);
496 else
497 mntpt = zfs_strdup(hdl, mountpoint);
498
499 /*
500 * Unshare and unmount the filesystem
501 */
502 if (zfs_unshare_proto(zhp, mntpt, share_all_proto) != 0)
503 return (-1);
504
505 if (unmount_one(hdl, mntpt, flags) != 0) {
506 free(mntpt);
507 (void) zfs_shareall(zhp);
508 return (-1);
509 }
510 libzfs_mnttab_remove(hdl, zhp->zfs_name);
511 free(mntpt);
512 }
513
514 return (0);
515 }
516
517 /*
518 * Unmount this filesystem and any children inheriting the mountpoint property.
519 * To do this, just act like we're changing the mountpoint property, but don't
520 * remount the filesystems afterwards.
521 */
522 int
523 zfs_unmountall(zfs_handle_t *zhp, int flags)
524 {
525 prop_changelist_t *clp;
526 int ret;
527
528 clp = changelist_gather(zhp, ZFS_PROP_MOUNTPOINT, 0, flags);
529 if (clp == NULL)
530 return (-1);
531
532 ret = changelist_prefix(clp);
533 changelist_free(clp);
534
535 return (ret);
536 }
537
538 boolean_t
539 zfs_is_shared(zfs_handle_t *zhp)
540 {
541 zfs_share_type_t rc = 0;
542 zfs_share_proto_t *curr_proto;
543
544 if (ZFS_IS_VOLUME(zhp))
545 return (B_FALSE);
546
547 for (curr_proto = share_all_proto; *curr_proto != PROTO_END;
548 curr_proto++)
549 rc |= zfs_is_shared_proto(zhp, NULL, *curr_proto);
550
551 return (rc ? B_TRUE : B_FALSE);
552 }
553
554 int
555 zfs_share(zfs_handle_t *zhp)
556 {
557 assert(!ZFS_IS_VOLUME(zhp));
558 return (zfs_share_proto(zhp, share_all_proto));
559 }
560
561 int
562 zfs_unshare(zfs_handle_t *zhp)
563 {
564 assert(!ZFS_IS_VOLUME(zhp));
565 return (zfs_unshareall(zhp));
566 }
567
568 /*
569 * Check to see if the filesystem is currently shared.
570 */
571 zfs_share_type_t
572 zfs_is_shared_proto(zfs_handle_t *zhp, char **where, zfs_share_proto_t proto)
573 {
574 char *mountpoint;
575 zfs_share_type_t rc;
576
577 if (!zfs_is_mounted(zhp, &mountpoint))
578 return (SHARED_NOT_SHARED);
579
580 if ((rc = is_shared(zhp->zfs_hdl, mountpoint, proto))
581 != SHARED_NOT_SHARED) {
582 if (where != NULL)
583 *where = mountpoint;
584 else
585 free(mountpoint);
586 return (rc);
587 } else {
588 free(mountpoint);
589 return (SHARED_NOT_SHARED);
590 }
591 }
592
593 boolean_t
594 zfs_is_shared_nfs(zfs_handle_t *zhp, char **where)
595 {
596 return (zfs_is_shared_proto(zhp, where,
597 PROTO_NFS) != SHARED_NOT_SHARED);
598 }
599
600 boolean_t
601 zfs_is_shared_smb(zfs_handle_t *zhp, char **where)
602 {
603 return (zfs_is_shared_proto(zhp, where,
604 PROTO_SMB) != SHARED_NOT_SHARED);
605 }
606
607 /*
608 * Make sure things will work if libshare isn't installed by using
609 * wrapper functions that check to see that the pointers to functions
610 * initialized in _zfs_init_libshare() are actually present.
611 */
612
613 static sa_handle_t (*_sa_init)(int);
614 static sa_handle_t (*_sa_init_arg)(int, void *);
615 static void (*_sa_fini)(sa_handle_t);
616 static sa_share_t (*_sa_find_share)(sa_handle_t, char *);
617 static int (*_sa_enable_share)(sa_share_t, char *);
618 static int (*_sa_disable_share)(sa_share_t, char *);
619 static char *(*_sa_errorstr)(int);
620 static int (*_sa_parse_legacy_options)(sa_group_t, char *, char *);
621 static boolean_t (*_sa_needs_refresh)(sa_handle_t *);
622 static libzfs_handle_t *(*_sa_get_zfs_handle)(sa_handle_t);
623 static int (*_sa_zfs_process_share)(sa_handle_t, sa_group_t, sa_share_t,
624 char *, char *, zprop_source_t, char *, char *, char *);
625 static void (*_sa_update_sharetab_ts)(sa_handle_t);
626
627 /*
628 * _zfs_init_libshare()
629 *
630 * Find the libshare.so.1 entry points that we use here and save the
631 * values to be used later. This is triggered by the runtime loader.
632 * Make sure the correct ISA version is loaded.
633 */
634
635 #pragma init(_zfs_init_libshare)
636 static void
637 _zfs_init_libshare(void)
638 {
639 void *libshare;
640 char path[MAXPATHLEN];
641 char isa[MAXISALEN];
642
643 #if defined(_LP64)
644 if (sysinfo(SI_ARCHITECTURE_64, isa, MAXISALEN) == -1)
645 isa[0] = '\0';
646 #else
647 isa[0] = '\0';
648 #endif
649 (void) snprintf(path, MAXPATHLEN,
650 "/usr/lib/%s/libshare.so.1", isa);
651
652 if ((libshare = dlopen(path, RTLD_LAZY | RTLD_GLOBAL)) != NULL) {
653 _sa_init = (sa_handle_t (*)(int))dlsym(libshare, "sa_init");
654 _sa_init_arg = (sa_handle_t (*)(int, void *))dlsym(libshare,
655 "sa_init_arg");
656 _sa_fini = (void (*)(sa_handle_t))dlsym(libshare, "sa_fini");
657 _sa_find_share = (sa_share_t (*)(sa_handle_t, char *))
658 dlsym(libshare, "sa_find_share");
659 _sa_enable_share = (int (*)(sa_share_t, char *))dlsym(libshare,
660 "sa_enable_share");
661 _sa_disable_share = (int (*)(sa_share_t, char *))dlsym(libshare,
662 "sa_disable_share");
663 _sa_errorstr = (char *(*)(int))dlsym(libshare, "sa_errorstr");
664 _sa_parse_legacy_options = (int (*)(sa_group_t, char *, char *))
665 dlsym(libshare, "sa_parse_legacy_options");
666 _sa_needs_refresh = (boolean_t (*)(sa_handle_t *))
667 dlsym(libshare, "sa_needs_refresh");
668 _sa_get_zfs_handle = (libzfs_handle_t *(*)(sa_handle_t))
669 dlsym(libshare, "sa_get_zfs_handle");
670 _sa_zfs_process_share = (int (*)(sa_handle_t, sa_group_t,
671 sa_share_t, char *, char *, zprop_source_t, char *,
672 char *, char *))dlsym(libshare, "sa_zfs_process_share");
673 _sa_update_sharetab_ts = (void (*)(sa_handle_t))
674 dlsym(libshare, "sa_update_sharetab_ts");
675 if (_sa_init == NULL || _sa_init_arg == NULL ||
676 _sa_fini == NULL || _sa_find_share == NULL ||
677 _sa_enable_share == NULL || _sa_disable_share == NULL ||
678 _sa_errorstr == NULL || _sa_parse_legacy_options == NULL ||
679 _sa_needs_refresh == NULL || _sa_get_zfs_handle == NULL ||
680 _sa_zfs_process_share == NULL ||
681 _sa_update_sharetab_ts == NULL) {
682 _sa_init = NULL;
683 _sa_init_arg = NULL;
684 _sa_fini = NULL;
685 _sa_disable_share = NULL;
686 _sa_enable_share = NULL;
687 _sa_errorstr = NULL;
688 _sa_parse_legacy_options = NULL;
689 (void) dlclose(libshare);
690 _sa_needs_refresh = NULL;
691 _sa_get_zfs_handle = NULL;
692 _sa_zfs_process_share = NULL;
693 _sa_update_sharetab_ts = NULL;
694 }
695 }
696 }
697
698 /*
699 * zfs_init_libshare(zhandle, service)
700 *
701 * Initialize the libshare API if it hasn't already been initialized.
702 * In all cases it returns 0 if it succeeded and an error if not. The
703 * service value is which part(s) of the API to initialize and is a
704 * direct map to the libshare sa_init(service) interface.
705 */
706 static int
707 zfs_init_libshare_impl(libzfs_handle_t *zhandle, int service, void *arg)
708 {
709 /*
710 * libshare is either not installed or we're in a branded zone. The
711 * rest of the wrapper functions around the libshare calls already
712 * handle NULL function pointers, but we don't want the callers of
713 * zfs_init_libshare() to fail prematurely if libshare is not available.
714 */
715 if (_sa_init == NULL)
716 return (SA_OK);
717
718 /*
719 * Attempt to refresh libshare. This is necessary if there was a cache
720 * miss for a new ZFS dataset that was just created, or if state of the
721 * sharetab file has changed since libshare was last initialized. We
722 * want to make sure so check timestamps to see if a different process
723 * has updated any of the configuration. If there was some non-ZFS
724 * change, we need to re-initialize the internal cache.
725 */
726 if (_sa_needs_refresh != NULL &&
727 _sa_needs_refresh(zhandle->libzfs_sharehdl)) {
728 zfs_uninit_libshare(zhandle);
729 zhandle->libzfs_sharehdl = _sa_init_arg(service, arg);
730 }
731
732 if (zhandle && zhandle->libzfs_sharehdl == NULL)
733 zhandle->libzfs_sharehdl = _sa_init_arg(service, arg);
734
735 if (zhandle->libzfs_sharehdl == NULL)
736 return (SA_NO_MEMORY);
737
738 return (SA_OK);
739 }
740 int
741 zfs_init_libshare(libzfs_handle_t *zhandle, int service)
742 {
743 return (zfs_init_libshare_impl(zhandle, service, NULL));
744 }
745
746 int
747 zfs_init_libshare_arg(libzfs_handle_t *zhandle, int service, void *arg)
748 {
749 return (zfs_init_libshare_impl(zhandle, service, arg));
750 }
751
752
753 /*
754 * zfs_uninit_libshare(zhandle)
755 *
756 * Uninitialize the libshare API if it hasn't already been
757 * uninitialized. It is OK to call multiple times.
758 */
759 void
760 zfs_uninit_libshare(libzfs_handle_t *zhandle)
761 {
762 if (zhandle != NULL && zhandle->libzfs_sharehdl != NULL) {
763 if (_sa_fini != NULL)
764 _sa_fini(zhandle->libzfs_sharehdl);
765 zhandle->libzfs_sharehdl = NULL;
766 }
767 }
768
769 /*
770 * zfs_parse_options(options, proto)
771 *
772 * Call the legacy parse interface to get the protocol specific
773 * options using the NULL arg to indicate that this is a "parse" only.
774 */
775 int
776 zfs_parse_options(char *options, zfs_share_proto_t proto)
777 {
778 if (_sa_parse_legacy_options != NULL) {
779 return (_sa_parse_legacy_options(NULL, options,
780 proto_table[proto].p_name));
781 }
782 return (SA_CONFIG_ERR);
783 }
784
785 /*
786 * zfs_sa_find_share(handle, path)
787 *
788 * wrapper around sa_find_share to find a share path in the
789 * configuration.
790 */
791 static sa_share_t
792 zfs_sa_find_share(sa_handle_t handle, char *path)
793 {
794 if (_sa_find_share != NULL)
795 return (_sa_find_share(handle, path));
796 return (NULL);
797 }
798
799 /*
800 * zfs_sa_enable_share(share, proto)
801 *
802 * Wrapper for sa_enable_share which enables a share for a specified
803 * protocol.
804 */
805 static int
806 zfs_sa_enable_share(sa_share_t share, char *proto)
807 {
808 if (_sa_enable_share != NULL)
809 return (_sa_enable_share(share, proto));
810 return (SA_CONFIG_ERR);
811 }
812
813 /*
814 * zfs_sa_disable_share(share, proto)
815 *
816 * Wrapper for sa_enable_share which disables a share for a specified
817 * protocol.
818 */
819 static int
820 zfs_sa_disable_share(sa_share_t share, char *proto)
821 {
822 if (_sa_disable_share != NULL)
823 return (_sa_disable_share(share, proto));
824 return (SA_CONFIG_ERR);
825 }
826
827 /*
828 * Share the given filesystem according to the options in the specified
829 * protocol specific properties (sharenfs, sharesmb). We rely
830 * on "libshare" to the dirty work for us.
831 */
832 static int
833 zfs_share_proto(zfs_handle_t *zhp, zfs_share_proto_t *proto)
834 {
835 char mountpoint[ZFS_MAXPROPLEN];
836 char shareopts[ZFS_MAXPROPLEN];
837 char sourcestr[ZFS_MAXPROPLEN];
838 libzfs_handle_t *hdl = zhp->zfs_hdl;
839 sa_share_t share;
840 zfs_share_proto_t *curr_proto;
841 zprop_source_t sourcetype;
842 int ret;
843
844 if (!zfs_is_mountable(zhp, mountpoint, sizeof (mountpoint), NULL))
845 return (0);
846
847 for (curr_proto = proto; *curr_proto != PROTO_END; curr_proto++) {
848 /*
849 * Return success if there are no share options.
850 */
851 if (zfs_prop_get(zhp, proto_table[*curr_proto].p_prop,
852 shareopts, sizeof (shareopts), &sourcetype, sourcestr,
853 ZFS_MAXPROPLEN, B_FALSE) != 0 ||
854 strcmp(shareopts, "off") == 0)
855 continue;
856 ret = zfs_init_libshare_arg(hdl, SA_INIT_ONE_SHARE_FROM_HANDLE,
857 zhp);
858 if (ret != SA_OK) {
859 (void) zfs_error_fmt(hdl, EZFS_SHARENFSFAILED,
860 dgettext(TEXT_DOMAIN, "cannot share '%s': %s"),
861 zfs_get_name(zhp), _sa_errorstr != NULL ?
862 _sa_errorstr(ret) : "");
863 return (-1);
864 }
865
866 /*
867 * If the 'zoned' property is set, then zfs_is_mountable()
868 * will have already bailed out if we are in the global zone.
869 * But local zones cannot be NFS servers, so we ignore it for
870 * local zones as well.
871 */
872 if (zfs_prop_get_int(zhp, ZFS_PROP_ZONED))
873 continue;
874
875 share = zfs_sa_find_share(hdl->libzfs_sharehdl, mountpoint);
876 if (share == NULL) {
877 /*
878 * This may be a new file system that was just
879 * created so isn't in the internal cache
880 * (second time through). Rather than
881 * reloading the entire configuration, we can
882 * assume ZFS has done the checking and it is
883 * safe to add this to the internal
884 * configuration.
885 */
886 if (_sa_zfs_process_share(hdl->libzfs_sharehdl,
887 NULL, NULL, mountpoint,
888 proto_table[*curr_proto].p_name, sourcetype,
889 shareopts, sourcestr, zhp->zfs_name) != SA_OK) {
890 (void) zfs_error_fmt(hdl,
891 proto_table[*curr_proto].p_share_err,
892 dgettext(TEXT_DOMAIN, "cannot share '%s'"),
893 zfs_get_name(zhp));
894 return (-1);
895 }
896 share = zfs_sa_find_share(hdl->libzfs_sharehdl,
897 mountpoint);
898 }
899 if (share != NULL) {
900 int err;
901 err = zfs_sa_enable_share(share,
902 proto_table[*curr_proto].p_name);
903 if (err != SA_OK) {
904 (void) zfs_error_fmt(hdl,
905 proto_table[*curr_proto].p_share_err,
906 dgettext(TEXT_DOMAIN, "cannot share '%s'"),
907 zfs_get_name(zhp));
908 return (-1);
909 }
910 } else {
911 (void) zfs_error_fmt(hdl,
912 proto_table[*curr_proto].p_share_err,
913 dgettext(TEXT_DOMAIN, "cannot share '%s'"),
914 zfs_get_name(zhp));
915 return (-1);
916 }
917
918 }
919 return (0);
920 }
921
922
923 int
924 zfs_share_nfs(zfs_handle_t *zhp)
925 {
926 return (zfs_share_proto(zhp, nfs_only));
927 }
928
929 int
930 zfs_share_smb(zfs_handle_t *zhp)
931 {
932 return (zfs_share_proto(zhp, smb_only));
933 }
934
935 int
936 zfs_shareall(zfs_handle_t *zhp)
937 {
938 return (zfs_share_proto(zhp, share_all_proto));
939 }
940
941 /*
942 * Unshare a filesystem by mountpoint.
943 */
944 static int
945 unshare_one(libzfs_handle_t *hdl, const char *name, const char *mountpoint,
946 zfs_share_proto_t proto)
947 {
948 sa_share_t share;
949 int err;
950 char *mntpt;
951
952 /*
953 * Mountpoint could get trashed if libshare calls getmntany
954 * which it does during API initialization, so strdup the
955 * value.
956 */
957 mntpt = zfs_strdup(hdl, mountpoint);
958
959 /*
960 * make sure libshare initialized, initialize everything because we
961 * don't know what other unsharing may happen later. Functions up the
962 * stack are allowed to initialize instead a subset of shares at the
963 * time the set is known.
964 */
965 if ((err = zfs_init_libshare_arg(hdl, SA_INIT_ONE_SHARE_FROM_NAME,
966 (void *)name)) != SA_OK) {
967 free(mntpt); /* don't need the copy anymore */
968 return (zfs_error_fmt(hdl, proto_table[proto].p_unshare_err,
969 dgettext(TEXT_DOMAIN, "cannot unshare '%s': %s"),
970 name, _sa_errorstr(err)));
971 }
972
973 share = zfs_sa_find_share(hdl->libzfs_sharehdl, mntpt);
974 free(mntpt); /* don't need the copy anymore */
975
976 if (share != NULL) {
977 err = zfs_sa_disable_share(share, proto_table[proto].p_name);
978 if (err != SA_OK) {
979 return (zfs_error_fmt(hdl,
980 proto_table[proto].p_unshare_err,
981 dgettext(TEXT_DOMAIN, "cannot unshare '%s': %s"),
982 name, _sa_errorstr(err)));
983 }
984 } else {
985 return (zfs_error_fmt(hdl, proto_table[proto].p_unshare_err,
986 dgettext(TEXT_DOMAIN, "cannot unshare '%s': not found"),
987 name));
988 }
989 return (0);
990 }
991
992 /*
993 * Unshare the given filesystem.
994 */
995 int
996 zfs_unshare_proto(zfs_handle_t *zhp, const char *mountpoint,
997 zfs_share_proto_t *proto)
998 {
999 libzfs_handle_t *hdl = zhp->zfs_hdl;
1000 struct mnttab entry;
1001 char *mntpt = NULL;
1002
1003 /* check to see if need to unmount the filesystem */
1004 rewind(zhp->zfs_hdl->libzfs_mnttab);
1005 if (mountpoint != NULL)
1006 mountpoint = mntpt = zfs_strdup(hdl, mountpoint);
1007
1008 if (mountpoint != NULL || ((zfs_get_type(zhp) == ZFS_TYPE_FILESYSTEM) &&
1009 libzfs_mnttab_find(hdl, zfs_get_name(zhp), &entry) == 0)) {
1010 zfs_share_proto_t *curr_proto;
1011
1012 if (mountpoint == NULL)
1013 mntpt = zfs_strdup(zhp->zfs_hdl, entry.mnt_mountp);
1014
1015 for (curr_proto = proto; *curr_proto != PROTO_END;
1016 curr_proto++) {
1017
1018 if (is_shared(hdl, mntpt, *curr_proto) &&
1019 unshare_one(hdl, zhp->zfs_name,
1020 mntpt, *curr_proto) != 0) {
1021 if (mntpt != NULL)
1022 free(mntpt);
1023 return (-1);
1024 }
1025 }
1026 }
1027 if (mntpt != NULL)
1028 free(mntpt);
1029
1030 return (0);
1031 }
1032
1033 int
1034 zfs_unshare_nfs(zfs_handle_t *zhp, const char *mountpoint)
1035 {
1036 return (zfs_unshare_proto(zhp, mountpoint, nfs_only));
1037 }
1038
1039 int
1040 zfs_unshare_smb(zfs_handle_t *zhp, const char *mountpoint)
1041 {
1042 return (zfs_unshare_proto(zhp, mountpoint, smb_only));
1043 }
1044
1045 /*
1046 * Same as zfs_unmountall(), but for NFS and SMB unshares.
1047 */
1048 int
1049 zfs_unshareall_proto(zfs_handle_t *zhp, zfs_share_proto_t *proto)
1050 {
1051 prop_changelist_t *clp;
1052 int ret;
1053
1054 clp = changelist_gather(zhp, ZFS_PROP_SHARENFS, 0, 0);
1055 if (clp == NULL)
1056 return (-1);
1057
1058 ret = changelist_unshare(clp, proto);
1059 changelist_free(clp);
1060
1061 return (ret);
1062 }
1063
1064 int
1065 zfs_unshareall_nfs(zfs_handle_t *zhp)
1066 {
1067 return (zfs_unshareall_proto(zhp, nfs_only));
1068 }
1069
1070 int
1071 zfs_unshareall_smb(zfs_handle_t *zhp)
1072 {
1073 return (zfs_unshareall_proto(zhp, smb_only));
1074 }
1075
1076 int
1077 zfs_unshareall(zfs_handle_t *zhp)
1078 {
1079 return (zfs_unshareall_proto(zhp, share_all_proto));
1080 }
1081
1082 int
1083 zfs_unshareall_bypath(zfs_handle_t *zhp, const char *mountpoint)
1084 {
1085 return (zfs_unshare_proto(zhp, mountpoint, share_all_proto));
1086 }
1087
1088 /*
1089 * Remove the mountpoint associated with the current dataset, if necessary.
1090 * We only remove the underlying directory if:
1091 *
1092 * - The mountpoint is not 'none' or 'legacy'
1093 * - The mountpoint is non-empty
1094 * - The mountpoint is the default or inherited
1095 * - The 'zoned' property is set, or we're in a local zone
1096 *
1097 * Any other directories we leave alone.
1098 */
1099 void
1100 remove_mountpoint(zfs_handle_t *zhp)
1101 {
1102 char mountpoint[ZFS_MAXPROPLEN];
1103 zprop_source_t source;
1104
1105 if (!zfs_is_mountable(zhp, mountpoint, sizeof (mountpoint),
1106 &source))
1107 return;
1108
1109 if (source == ZPROP_SRC_DEFAULT ||
1110 source == ZPROP_SRC_INHERITED) {
1111 /*
1112 * Try to remove the directory, silently ignoring any errors.
1113 * The filesystem may have since been removed or moved around,
1114 * and this error isn't really useful to the administrator in
1115 * any way.
1116 */
1117 (void) rmdir(mountpoint);
1118 }
1119 }
1120
1121 /*
1122 * Add the given zfs handle to the cb_handles array, dynamically reallocating
1123 * the array if it is out of space.
1124 */
1125 void
1126 libzfs_add_handle(get_all_cb_t *cbp, zfs_handle_t *zhp)
1127 {
1128 if (cbp->cb_alloc == cbp->cb_used) {
1129 size_t newsz;
1130 zfs_handle_t **newhandles;
1131
1132 newsz = cbp->cb_alloc != 0 ? cbp->cb_alloc * 2 : 64;
1133 newhandles = zfs_realloc(zhp->zfs_hdl,
1134 cbp->cb_handles, cbp->cb_alloc * sizeof (zfs_handle_t *),
1135 newsz * sizeof (zfs_handle_t *));
1136 cbp->cb_handles = newhandles;
1137 cbp->cb_alloc = newsz;
1138 }
1139 cbp->cb_handles[cbp->cb_used++] = zhp;
1140 }
1141
1142 /*
1143 * Recursive helper function used during file system enumeration
1144 */
1145 static int
1146 zfs_iter_cb(zfs_handle_t *zhp, void *data)
1147 {
1148 get_all_cb_t *cbp = data;
1149
1150 if (!(zfs_get_type(zhp) & ZFS_TYPE_FILESYSTEM)) {
1151 zfs_close(zhp);
1152 return (0);
1153 }
1154
1155 if (zfs_prop_get_int(zhp, ZFS_PROP_CANMOUNT) == ZFS_CANMOUNT_NOAUTO) {
1156 zfs_close(zhp);
1157 return (0);
1158 }
1159
1160 if (zfs_prop_get_int(zhp, ZFS_PROP_KEYSTATUS) ==
1161 ZFS_KEYSTATUS_UNAVAILABLE) {
1162 zfs_close(zhp);
1163 return (0);
1164 }
1165
1166 /*
1167 * If this filesystem is inconsistent and has a receive resume
1168 * token, we can not mount it.
1169 */
1170 if (zfs_prop_get_int(zhp, ZFS_PROP_INCONSISTENT) &&
1171 zfs_prop_get(zhp, ZFS_PROP_RECEIVE_RESUME_TOKEN,
1172 NULL, 0, NULL, NULL, 0, B_TRUE) == 0) {
1173 zfs_close(zhp);
1174 return (0);
1175 }
1176
1177 libzfs_add_handle(cbp, zhp);
1178 if (zfs_iter_filesystems(zhp, zfs_iter_cb, cbp) != 0) {
1179 zfs_close(zhp);
1180 return (-1);
1181 }
1182 return (0);
1183 }
1184
1185 /*
1186 * Sort comparator that compares two mountpoint paths. We sort these paths so
1187 * that subdirectories immediately follow their parents. This means that we
1188 * effectively treat the '/' character as the lowest value non-nul char.
1189 * Since filesystems from non-global zones can have the same mountpoint
1190 * as other filesystems, the comparator sorts global zone filesystems to
1191 * the top of the list. This means that the global zone will traverse the
1192 * filesystem list in the correct order and can stop when it sees the
1193 * first zoned filesystem. In a non-global zone, only the delegated
1194 * filesystems are seen.
1195 *
1196 * An example sorted list using this comparator would look like:
1197 *
1198 * /foo
1199 * /foo/bar
1200 * /foo/bar/baz
1201 * /foo/baz
1202 * /foo.bar
1203 * /foo (NGZ1)
1204 * /foo (NGZ2)
1205 *
1206 * The mounting code depends on this ordering to deterministically iterate
1207 * over filesystems in order to spawn parallel mount tasks.
1208 */
1209 static int
1210 mountpoint_cmp(const void *arga, const void *argb)
1211 {
1212 zfs_handle_t *const *zap = arga;
1213 zfs_handle_t *za = *zap;
1214 zfs_handle_t *const *zbp = argb;
1215 zfs_handle_t *zb = *zbp;
1216 char mounta[MAXPATHLEN];
1217 char mountb[MAXPATHLEN];
1218 const char *a = mounta;
1219 const char *b = mountb;
1220 boolean_t gota, gotb;
1221 uint64_t zoneda, zonedb;
1222
1223 zoneda = zfs_prop_get_int(za, ZFS_PROP_ZONED);
1224 zonedb = zfs_prop_get_int(zb, ZFS_PROP_ZONED);
1225 if (zoneda && !zonedb)
1226 return (1);
1227 if (!zoneda && zonedb)
1228 return (-1);
1229
1230 gota = (zfs_get_type(za) == ZFS_TYPE_FILESYSTEM);
1231 if (gota) {
1232 verify(zfs_prop_get(za, ZFS_PROP_MOUNTPOINT, mounta,
1233 sizeof (mounta), NULL, NULL, 0, B_FALSE) == 0);
1234 }
1235 gotb = (zfs_get_type(zb) == ZFS_TYPE_FILESYSTEM);
1236 if (gotb) {
1237 verify(zfs_prop_get(zb, ZFS_PROP_MOUNTPOINT, mountb,
1238 sizeof (mountb), NULL, NULL, 0, B_FALSE) == 0);
1239 }
1240
1241 if (gota && gotb) {
1242 while (*a != '\0' && (*a == *b)) {
1243 a++;
1244 b++;
1245 }
1246 if (*a == *b)
1247 return (0);
1248 if (*a == '\0')
1249 return (-1);
1250 if (*b == '\0')
1251 return (1);
1252 if (*a == '/')
1253 return (-1);
1254 if (*b == '/')
1255 return (1);
1256 return (*a < *b ? -1 : *a > *b);
1257 }
1258
1259 if (gota)
1260 return (-1);
1261 if (gotb)
1262 return (1);
1263
1264 /*
1265 * If neither filesystem has a mountpoint, revert to sorting by
1266 * dataset name.
1267 */
1268 return (strcmp(zfs_get_name(za), zfs_get_name(zb)));
1269 }
1270
1271 /*
1272 * Return true if path2 is a child of path1.
1273 */
1274 static boolean_t
1275 libzfs_path_contains(const char *path1, const char *path2)
1276 {
1277 return (strstr(path2, path1) == path2 && path2[strlen(path1)] == '/');
1278 }
1279
1280 /*
1281 * Given a mountpoint specified by idx in the handles array, find the first
1282 * non-descendent of that mountpoint and return its index. Descendant paths
1283 * start with the parent's path. This function relies on the ordering
1284 * enforced by mountpoint_cmp().
1285 */
1286 static int
1287 non_descendant_idx(zfs_handle_t **handles, size_t num_handles, int idx)
1288 {
1289 char parent[ZFS_MAXPROPLEN];
1290 char child[ZFS_MAXPROPLEN];
1291 int i;
1292
1293 verify(zfs_prop_get(handles[idx], ZFS_PROP_MOUNTPOINT, parent,
1294 sizeof (parent), NULL, NULL, 0, B_FALSE) == 0);
1295
1296 for (i = idx + 1; i < num_handles; i++) {
1297 verify(zfs_prop_get(handles[i], ZFS_PROP_MOUNTPOINT, child,
1298 sizeof (child), NULL, NULL, 0, B_FALSE) == 0);
1299 if (!libzfs_path_contains(parent, child))
1300 break;
1301 }
1302 return (i);
1303 }
1304
1305 typedef struct mnt_param {
1306 libzfs_handle_t *mnt_hdl;
1307 zfs_taskq_t *mnt_tq;
1308 zfs_handle_t **mnt_zhps; /* filesystems to mount */
1309 size_t mnt_num_handles;
1310 int mnt_idx; /* Index of selected entry to mount */
1311 zfs_iter_f mnt_func;
1312 void *mnt_data;
1313 } mnt_param_t;
1314
1315 /*
1316 * Allocate and populate the parameter struct for mount function, and
1317 * schedule mounting of the entry selected by idx.
1318 */
1319 static void
1320 zfs_dispatch_mount(libzfs_handle_t *hdl, zfs_handle_t **handles,
1321 size_t num_handles, int idx, zfs_iter_f func, void *data, zfs_taskq_t *tq)
1322 {
1323 mnt_param_t *mnt_param = zfs_alloc(hdl, sizeof (mnt_param_t));
1324
1325 mnt_param->mnt_hdl = hdl;
1326 mnt_param->mnt_tq = tq;
1327 mnt_param->mnt_zhps = handles;
1328 mnt_param->mnt_num_handles = num_handles;
1329 mnt_param->mnt_idx = idx;
1330 mnt_param->mnt_func = func;
1331 mnt_param->mnt_data = data;
1332
1333 (void) zfs_taskq_dispatch(tq, zfs_mount_task, (void*)mnt_param,
1334 ZFS_TQ_SLEEP);
1335 }
1336
1337 /*
1338 * This is the structure used to keep state of mounting or sharing operations
1339 * during a call to zpool_enable_datasets().
1340 */
1341 typedef struct mount_state {
1342 /*
1343 * ms_mntstatus is set to -1 if any mount fails. While multiple threads
1344 * could update this variable concurrently, no synchronization is
1345 * needed as it's only ever set to -1.
1346 */
1347 int ms_mntstatus;
1348 int ms_mntflags;
1349 const char *ms_mntopts;
1350 } mount_state_t;
1351
1352 static int
1353 zfs_mount_one(zfs_handle_t *zhp, void *arg)
1354 {
1355 mount_state_t *ms = arg;
1356 int ret = 0;
1357
1358 if (zfs_prop_get_int(zhp, ZFS_PROP_KEYSTATUS) ==
1359 ZFS_KEYSTATUS_UNAVAILABLE)
1360 return (0);
1361
1362 if (zfs_mount(zhp, ms->ms_mntopts, ms->ms_mntflags) != 0)
1363 ret = ms->ms_mntstatus = -1;
1364 return (ret);
1365 }
1366
1367 static int
1368 zfs_share_one(zfs_handle_t *zhp, void *arg)
1369 {
1370 mount_state_t *ms = arg;
1371 int ret = 0;
1372
1373 if (zfs_share(zhp) != 0)
1374 ret = ms->ms_mntstatus = -1;
1375 return (ret);
1376 }
1377
1378 /*
1379 * Task queue function to mount one file system. On completion, it finds and
1380 * schedules its children to be mounted. This depends on the sorting done in
1381 * zfs_foreach_mountpoint(). Note that the degenerate case (chain of entries
1382 * each descending from the previous) will have no parallelism since we always
1383 * have to wait for the parent to finish mounting before we can schedule
1384 * its children.
1385 */
1386 static void
1387 zfs_mount_task(void *arg)
1388 {
1389 mnt_param_t *mp = arg;
1390 int idx = mp->mnt_idx;
1391 zfs_handle_t **handles = mp->mnt_zhps;
1392 size_t num_handles = mp->mnt_num_handles;
1393 char mountpoint[ZFS_MAXPROPLEN];
1394
1395 verify(zfs_prop_get(handles[idx], ZFS_PROP_MOUNTPOINT, mountpoint,
1396 sizeof (mountpoint), NULL, NULL, 0, B_FALSE) == 0);
1397
1398 if (mp->mnt_func(handles[idx], mp->mnt_data) != 0)
1399 return;
1400
1401 /*
1402 * We dispatch tasks to mount filesystems with mountpoints underneath
1403 * this one. We do this by dispatching the next filesystem with a
1404 * descendant mountpoint of the one we just mounted, then skip all of
1405 * its descendants, dispatch the next descendant mountpoint, and so on.
1406 * The non_descendant_idx() function skips over filesystems that are
1407 * descendants of the filesystem we just dispatched.
1408 */
1409 for (int i = idx + 1; i < num_handles;
1410 i = non_descendant_idx(handles, num_handles, i)) {
1411 char child[ZFS_MAXPROPLEN];
1412 verify(zfs_prop_get(handles[i], ZFS_PROP_MOUNTPOINT,
1413 child, sizeof (child), NULL, NULL, 0, B_FALSE) == 0);
1414
1415 if (!libzfs_path_contains(mountpoint, child))
1416 break; /* not a descendant, return */
1417 zfs_dispatch_mount(mp->mnt_hdl, handles, num_handles, i,
1418 mp->mnt_func, mp->mnt_data, mp->mnt_tq);
1419 }
1420 free(mp);
1421 }
1422
1423 /*
1424 * Issue the func callback for each ZFS handle contained in the handles
1425 * array. This function is used to mount all datasets, and so this function
1426 * guarantees that filesystems for parent mountpoints are called before their
1427 * children. As such, before issuing any callbacks, we first sort the array
1428 * of handles by mountpoint.
1429 *
1430 * Callbacks are issued in one of two ways:
1431 *
1432 * 1. Sequentially: If the parallel argument is B_FALSE or the ZFS_SERIAL_MOUNT
1433 * environment variable is set, then we issue callbacks sequentially.
1434 *
1435 * 2. In parallel: If the parallel argument is B_TRUE and the ZFS_SERIAL_MOUNT
1436 * environment variable is not set, then we use a taskq to dispatch threads
1437 * to mount filesystems is parallel. This function dispatches tasks to mount
1438 * the filesystems at the top-level mountpoints, and these tasks in turn
1439 * are responsible for recursively mounting filesystems in their children
1440 * mountpoints.
1441 */
1442 void
1443 zfs_foreach_mountpoint(libzfs_handle_t *hdl, zfs_handle_t **handles,
1444 size_t num_handles, zfs_iter_f func, void *data, boolean_t parallel)
1445 {
1446 zoneid_t zoneid = getzoneid();
1447
1448 /*
1449 * The ZFS_SERIAL_MOUNT environment variable is an undocumented
1450 * variable that can be used as a convenience to do a/b comparison
1451 * of serial vs. parallel mounting.
1452 */
1453 boolean_t serial_mount = !parallel ||
1454 (getenv("ZFS_SERIAL_MOUNT") != NULL);
1455
1456 /*
1457 * Sort the datasets by mountpoint. See mountpoint_cmp for details
1458 * of how these are sorted.
1459 */
1460 qsort(handles, num_handles, sizeof (zfs_handle_t *), mountpoint_cmp);
1461
1462 if (serial_mount) {
1463 for (int i = 0; i < num_handles; i++) {
1464 func(handles[i], data);
1465 }
1466 return;
1467 }
1468
1469 /*
1470 * Issue the callback function for each dataset using a parallel
1471 * algorithm that uses a taskq to manage threads.
1472 */
1473 zfs_taskq_t *tq = zfs_taskq_create("mount_taskq", mount_tq_nthr, 0,
1474 mount_tq_nthr, mount_tq_nthr, ZFS_TASKQ_PREPOPULATE);
1475
1476 /*
1477 * There may be multiple "top level" mountpoints outside of the pool's
1478 * root mountpoint, e.g.: /foo /bar. Dispatch a mount task for each of
1479 * these.
1480 */
1481 for (int i = 0; i < num_handles;
1482 i = non_descendant_idx(handles, num_handles, i)) {
1483 /*
1484 * Since the mountpoints have been sorted so that the zoned
1485 * filesystems are at the end, a zoned filesystem seen from
1486 * the global zone means that we're done.
1487 */
1488 if (zoneid == GLOBAL_ZONEID &&
1489 zfs_prop_get_int(handles[i], ZFS_PROP_ZONED))
1490 break;
1491 zfs_dispatch_mount(hdl, handles, num_handles, i, func, data,
1492 tq);
1493 }
1494
1495 zfs_taskq_wait(tq); /* wait for all scheduled mounts to complete */
1496 zfs_taskq_destroy(tq);
1497 }
1498
1499 /*
1500 * Mount and share all datasets within the given pool. This assumes that no
1501 * datasets within the pool are currently mounted.
1502 */
1503 #pragma weak zpool_mount_datasets = zpool_enable_datasets
1504 int
1505 zpool_enable_datasets(zpool_handle_t *zhp, const char *mntopts, int flags)
1506 {
1507 get_all_cb_t cb = { 0 };
1508 mount_state_t ms = { 0 };
1509 zfs_handle_t *zfsp;
1510 sa_init_selective_arg_t sharearg;
1511 int ret = 0;
1512
1513 if ((zfsp = zfs_open(zhp->zpool_hdl, zhp->zpool_name,
1514 ZFS_TYPE_DATASET)) == NULL)
1515 goto out;
1516
1517
1518 /*
1519 * Gather all non-snapshot datasets within the pool. Start by adding
1520 * the root filesystem for this pool to the list, and then iterate
1521 * over all child filesystems.
1522 */
1523 libzfs_add_handle(&cb, zfsp);
1524 if (zfs_iter_filesystems(zfsp, zfs_iter_cb, &cb) != 0)
1525 goto out;
1526
1527 ms.ms_mntopts = mntopts;
1528 ms.ms_mntflags = flags;
1529 zfs_foreach_mountpoint(zhp->zpool_hdl, cb.cb_handles, cb.cb_used,
1530 zfs_mount_one, &ms, B_TRUE);
1531 if (ms.ms_mntstatus != 0)
1532 ret = ms.ms_mntstatus;
1533
1534 /*
1535 * Share all filesystems that need to be shared. This needs to be
1536 * a separate pass because libshare is not mt-safe, and so we need
1537 * to share serially.
1538 */
1539 sharearg.zhandle_arr = cb.cb_handles;
1540 sharearg.zhandle_len = cb.cb_used;
1541 if ((ret = zfs_init_libshare_arg(zhp->zpool_hdl,
1542 SA_INIT_SHARE_API_SELECTIVE, &sharearg)) != 0)
1543 goto out;
1544
1545 ms.ms_mntstatus = 0;
1546 zfs_foreach_mountpoint(zhp->zpool_hdl, cb.cb_handles, cb.cb_used,
1547 zfs_share_one, &ms, B_FALSE);
1548 if (ms.ms_mntstatus != 0)
1549 ret = ms.ms_mntstatus;
1550
1551 out:
1552 for (int i = 0; i < cb.cb_used; i++)
1553 zfs_close(cb.cb_handles[i]);
1554 free(cb.cb_handles);
1555
1556 return (ret);
1557 }
1558
1559 static int
1560 mountpoint_compare(const void *a, const void *b)
1561 {
1562 const char *mounta = *((char **)a);
1563 const char *mountb = *((char **)b);
1564
1565 return (strcmp(mountb, mounta));
1566 }
1567
1568 /* alias for 2002/240 */
1569 #pragma weak zpool_unmount_datasets = zpool_disable_datasets
1570 /*
1571 * Unshare and unmount all datasets within the given pool. We don't want to
1572 * rely on traversing the DSL to discover the filesystems within the pool,
1573 * because this may be expensive (if not all of them are mounted), and can fail
1574 * arbitrarily (on I/O error, for example). Instead, we walk /etc/mnttab and
1575 * gather all the filesystems that are currently mounted.
1576 */
1577 int
1578 zpool_disable_datasets(zpool_handle_t *zhp, boolean_t force)
1579 {
1580 int used, alloc;
1581 struct mnttab entry;
1582 size_t namelen;
1583 char **mountpoints = NULL;
1584 zfs_handle_t **datasets = NULL;
1585 libzfs_handle_t *hdl = zhp->zpool_hdl;
1586 int i;
1587 int ret = -1;
1588 int flags = (force ? MS_FORCE : 0);
1589 sa_init_selective_arg_t sharearg;
1590
1591 namelen = strlen(zhp->zpool_name);
1592
1593 rewind(hdl->libzfs_mnttab);
1594 used = alloc = 0;
1595 while (getmntent(hdl->libzfs_mnttab, &entry) == 0) {
1596 /*
1597 * Ignore non-ZFS entries.
1598 */
1599 if (entry.mnt_fstype == NULL ||
1600 strcmp(entry.mnt_fstype, MNTTYPE_ZFS) != 0)
1601 continue;
1602
1603 /*
1604 * Ignore filesystems not within this pool.
1605 */
1606 if (entry.mnt_mountp == NULL ||
1607 strncmp(entry.mnt_special, zhp->zpool_name, namelen) != 0 ||
1608 (entry.mnt_special[namelen] != '/' &&
1609 entry.mnt_special[namelen] != '\0'))
1610 continue;
1611
1612 /*
1613 * At this point we've found a filesystem within our pool. Add
1614 * it to our growing list.
1615 */
1616 if (used == alloc) {
1617 if (alloc == 0) {
1618 if ((mountpoints = zfs_alloc(hdl,
1619 8 * sizeof (void *))) == NULL)
1620 goto out;
1621
1622 if ((datasets = zfs_alloc(hdl,
1623 8 * sizeof (void *))) == NULL)
1624 goto out;
1625
1626 alloc = 8;
1627 } else {
1628 void *ptr;
1629
1630 if ((ptr = zfs_realloc(hdl, mountpoints,
1631 alloc * sizeof (void *),
1632 alloc * 2 * sizeof (void *))) == NULL)
1633 goto out;
1634 mountpoints = ptr;
1635
1636 if ((ptr = zfs_realloc(hdl, datasets,
1637 alloc * sizeof (void *),
1638 alloc * 2 * sizeof (void *))) == NULL)
1639 goto out;
1640 datasets = ptr;
1641
1642 alloc *= 2;
1643 }
1644 }
1645
1646 if ((mountpoints[used] = zfs_strdup(hdl,
1647 entry.mnt_mountp)) == NULL)
1648 goto out;
1649
1650 /*
1651 * This is allowed to fail, in case there is some I/O error. It
1652 * is only used to determine if we need to remove the underlying
1653 * mountpoint, so failure is not fatal.
1654 */
1655 datasets[used] = make_dataset_handle(hdl, entry.mnt_special);
1656
1657 used++;
1658 }
1659
1660 /*
1661 * At this point, we have the entire list of filesystems, so sort it by
1662 * mountpoint.
1663 */
1664 sharearg.zhandle_arr = datasets;
1665 sharearg.zhandle_len = used;
1666 ret = zfs_init_libshare_arg(hdl, SA_INIT_SHARE_API_SELECTIVE,
1667 &sharearg);
1668 if (ret != 0)
1669 goto out;
1670 qsort(mountpoints, used, sizeof (char *), mountpoint_compare);
1671
1672 /*
1673 * Walk through and first unshare everything.
1674 */
1675 for (i = 0; i < used; i++) {
1676 zfs_share_proto_t *curr_proto;
1677 for (curr_proto = share_all_proto; *curr_proto != PROTO_END;
1678 curr_proto++) {
1679 if (is_shared(hdl, mountpoints[i], *curr_proto) &&
1680 unshare_one(hdl, mountpoints[i],
1681 mountpoints[i], *curr_proto) != 0)
1682 goto out;
1683 }
1684 }
1685
1686 /*
1687 * Now unmount everything, removing the underlying directories as
1688 * appropriate.
1689 */
1690 for (i = 0; i < used; i++) {
1691 if (unmount_one(hdl, mountpoints[i], flags) != 0)
1692 goto out;
1693 }
1694
1695 for (i = 0; i < used; i++) {
1696 if (datasets[i])
1697 remove_mountpoint(datasets[i]);
1698 }
1699
1700 ret = 0;
1701 out:
1702 for (i = 0; i < used; i++) {
1703 if (datasets[i])
1704 zfs_close(datasets[i]);
1705 free(mountpoints[i]);
1706 }
1707 free(datasets);
1708 free(mountpoints);
1709
1710 return (ret);
1711 }