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 int (*_sa_service)(sa_handle_t);
616 static void (*_sa_fini)(sa_handle_t);
617 static sa_share_t (*_sa_find_share)(sa_handle_t, char *);
618 static int (*_sa_enable_share)(sa_share_t, char *);
619 static int (*_sa_disable_share)(sa_share_t, char *);
620 static char *(*_sa_errorstr)(int);
621 static int (*_sa_parse_legacy_options)(sa_group_t, char *, char *);
622 static boolean_t (*_sa_needs_refresh)(sa_handle_t *);
623 static libzfs_handle_t *(*_sa_get_zfs_handle)(sa_handle_t);
624 static int (*_sa_zfs_process_share)(sa_handle_t, sa_group_t, sa_share_t,
625 char *, char *, zprop_source_t, char *, char *, char *);
626 static void (*_sa_update_sharetab_ts)(sa_handle_t);
627
628 /*
629 * _zfs_init_libshare()
630 *
631 * Find the libshare.so.1 entry points that we use here and save the
632 * values to be used later. This is triggered by the runtime loader.
633 * Make sure the correct ISA version is loaded.
634 */
635
636 #pragma init(_zfs_init_libshare)
637 static void
638 _zfs_init_libshare(void)
639 {
640 void *libshare;
641 char path[MAXPATHLEN];
642 char isa[MAXISALEN];
643
644 #if defined(_LP64)
645 if (sysinfo(SI_ARCHITECTURE_64, isa, MAXISALEN) == -1)
646 isa[0] = '\0';
647 #else
648 isa[0] = '\0';
649 #endif
650 (void) snprintf(path, MAXPATHLEN,
651 "/usr/lib/%s/libshare.so.1", isa);
652
653 if ((libshare = dlopen(path, RTLD_LAZY | RTLD_GLOBAL)) != NULL) {
654 _sa_init = (sa_handle_t (*)(int))dlsym(libshare, "sa_init");
655 _sa_init_arg = (sa_handle_t (*)(int, void *))dlsym(libshare,
656 "sa_init_arg");
657 _sa_fini = (void (*)(sa_handle_t))dlsym(libshare, "sa_fini");
658 _sa_service = (int (*)(sa_handle_t))dlsym(libshare,
659 "sa_service");
660 _sa_find_share = (sa_share_t (*)(sa_handle_t, char *))
661 dlsym(libshare, "sa_find_share");
662 _sa_enable_share = (int (*)(sa_share_t, char *))dlsym(libshare,
663 "sa_enable_share");
664 _sa_disable_share = (int (*)(sa_share_t, char *))dlsym(libshare,
665 "sa_disable_share");
666 _sa_errorstr = (char *(*)(int))dlsym(libshare, "sa_errorstr");
667 _sa_parse_legacy_options = (int (*)(sa_group_t, char *, char *))
668 dlsym(libshare, "sa_parse_legacy_options");
669 _sa_needs_refresh = (boolean_t (*)(sa_handle_t *))
670 dlsym(libshare, "sa_needs_refresh");
671 _sa_get_zfs_handle = (libzfs_handle_t *(*)(sa_handle_t))
672 dlsym(libshare, "sa_get_zfs_handle");
673 _sa_zfs_process_share = (int (*)(sa_handle_t, sa_group_t,
674 sa_share_t, char *, char *, zprop_source_t, char *,
675 char *, char *))dlsym(libshare, "sa_zfs_process_share");
676 _sa_update_sharetab_ts = (void (*)(sa_handle_t))
677 dlsym(libshare, "sa_update_sharetab_ts");
678 if (_sa_init == NULL || _sa_init_arg == NULL ||
679 _sa_fini == NULL || _sa_find_share == NULL ||
680 _sa_enable_share == NULL || _sa_disable_share == NULL ||
681 _sa_errorstr == NULL || _sa_parse_legacy_options == NULL ||
682 _sa_needs_refresh == NULL || _sa_get_zfs_handle == NULL ||
683 _sa_zfs_process_share == NULL || _sa_service == NULL ||
684 _sa_update_sharetab_ts == NULL) {
685 _sa_init = NULL;
686 _sa_init_arg = NULL;
687 _sa_service = NULL;
688 _sa_fini = NULL;
689 _sa_disable_share = NULL;
690 _sa_enable_share = NULL;
691 _sa_errorstr = NULL;
692 _sa_parse_legacy_options = NULL;
693 (void) dlclose(libshare);
694 _sa_needs_refresh = NULL;
695 _sa_get_zfs_handle = NULL;
696 _sa_zfs_process_share = NULL;
697 _sa_update_sharetab_ts = NULL;
698 }
699 }
700 }
701
702 /*
703 * zfs_init_libshare(zhandle, service)
704 *
705 * Initialize the libshare API if it hasn't already been initialized.
706 * In all cases it returns 0 if it succeeded and an error if not. The
707 * service value is which part(s) of the API to initialize and is a
708 * direct map to the libshare sa_init(service) interface.
709 */
710 static int
711 zfs_init_libshare_impl(libzfs_handle_t *zhandle, int service, void *arg)
712 {
713 /*
714 * libshare is either not installed or we're in a branded zone. The
715 * rest of the wrapper functions around the libshare calls already
716 * handle NULL function pointers, but we don't want the callers of
717 * zfs_init_libshare() to fail prematurely if libshare is not available.
718 */
719 if (_sa_init == NULL)
720 return (SA_OK);
721
722 /*
723 * Attempt to refresh libshare. This is necessary if there was a cache
724 * miss for a new ZFS dataset that was just created, or if state of the
725 * sharetab file has changed since libshare was last initialized. We
726 * want to make sure so check timestamps to see if a different process
727 * has updated any of the configuration. If there was some non-ZFS
728 * change, we need to re-initialize the internal cache.
729 */
730 if (_sa_needs_refresh != NULL &&
731 _sa_needs_refresh(zhandle->libzfs_sharehdl)) {
732 zfs_uninit_libshare(zhandle);
733 zhandle->libzfs_sharehdl = _sa_init_arg(service, arg);
734 }
735
736 if (zhandle && zhandle->libzfs_sharehdl == NULL)
737 zhandle->libzfs_sharehdl = _sa_init_arg(service, arg);
738
739 if (zhandle->libzfs_sharehdl == NULL)
740 return (SA_NO_MEMORY);
741
742 return (SA_OK);
743 }
744 int
745 zfs_init_libshare(libzfs_handle_t *zhandle, int service)
746 {
747 return (zfs_init_libshare_impl(zhandle, service, NULL));
748 }
749
750 int
751 zfs_init_libshare_arg(libzfs_handle_t *zhandle, int service, void *arg)
752 {
753 return (zfs_init_libshare_impl(zhandle, service, arg));
754 }
755
756
757 /*
758 * zfs_uninit_libshare(zhandle)
759 *
760 * Uninitialize the libshare API if it hasn't already been
761 * uninitialized. It is OK to call multiple times.
762 */
763 void
764 zfs_uninit_libshare(libzfs_handle_t *zhandle)
765 {
766 if (zhandle != NULL && zhandle->libzfs_sharehdl != NULL) {
767 if (_sa_fini != NULL)
768 _sa_fini(zhandle->libzfs_sharehdl);
769 zhandle->libzfs_sharehdl = NULL;
770 }
771 }
772
773 /*
774 * zfs_parse_options(options, proto)
775 *
776 * Call the legacy parse interface to get the protocol specific
777 * options using the NULL arg to indicate that this is a "parse" only.
778 */
779 int
780 zfs_parse_options(char *options, zfs_share_proto_t proto)
781 {
782 if (_sa_parse_legacy_options != NULL) {
783 return (_sa_parse_legacy_options(NULL, options,
784 proto_table[proto].p_name));
785 }
786 return (SA_CONFIG_ERR);
787 }
788
789 /*
790 * zfs_sa_find_share(handle, path)
791 *
792 * wrapper around sa_find_share to find a share path in the
793 * configuration.
794 */
795 static sa_share_t
796 zfs_sa_find_share(sa_handle_t handle, char *path)
797 {
798 if (_sa_find_share != NULL)
799 return (_sa_find_share(handle, path));
800 return (NULL);
801 }
802
803 /*
804 * zfs_sa_enable_share(share, proto)
805 *
806 * Wrapper for sa_enable_share which enables a share for a specified
807 * protocol.
808 */
809 static int
810 zfs_sa_enable_share(sa_share_t share, char *proto)
811 {
812 if (_sa_enable_share != NULL)
813 return (_sa_enable_share(share, proto));
814 return (SA_CONFIG_ERR);
815 }
816
817 /*
818 * zfs_sa_disable_share(share, proto)
819 *
820 * Wrapper for sa_enable_share which disables a share for a specified
821 * protocol.
822 */
823 static int
824 zfs_sa_disable_share(sa_share_t share, char *proto)
825 {
826 if (_sa_disable_share != NULL)
827 return (_sa_disable_share(share, proto));
828 return (SA_CONFIG_ERR);
829 }
830
831 /*
832 * Share the given filesystem according to the options in the specified
833 * protocol specific properties (sharenfs, sharesmb). We rely
834 * on "libshare" to the dirty work for us.
835 */
836 static int
837 zfs_share_proto(zfs_handle_t *zhp, zfs_share_proto_t *proto)
838 {
839 char mountpoint[ZFS_MAXPROPLEN];
840 char shareopts[ZFS_MAXPROPLEN];
841 char sourcestr[ZFS_MAXPROPLEN];
842 libzfs_handle_t *hdl = zhp->zfs_hdl;
843 sa_share_t share;
844 zfs_share_proto_t *curr_proto;
845 zprop_source_t sourcetype;
846 int service = SA_INIT_ONE_SHARE_FROM_HANDLE;
847 int ret;
848
849 if (!zfs_is_mountable(zhp, mountpoint, sizeof (mountpoint), NULL))
850 return (0);
851
852 /*
853 * Function may be called in a loop from higher up stack, with libshare
854 * initialized for multiple shares (SA_INIT_SHARE_API_SELECTIVE).
855 * zfs_init_libshare_arg will refresh the handle's cache if necessary.
856 * In this case we do not want to switch to per share initialization.
857 * Specify SA_INIT_SHARE_API to do full refresh, if refresh required.
858 */
859 if ((hdl->libzfs_sharehdl != NULL) && (_sa_service != NULL) &&
860 (_sa_service(hdl->libzfs_sharehdl) ==
861 SA_INIT_SHARE_API_SELECTIVE)) {
862 service = SA_INIT_SHARE_API;
863 }
864
865 for (curr_proto = proto; *curr_proto != PROTO_END; curr_proto++) {
866 /*
867 * Return success if there are no share options.
868 */
869 if (zfs_prop_get(zhp, proto_table[*curr_proto].p_prop,
870 shareopts, sizeof (shareopts), &sourcetype, sourcestr,
871 ZFS_MAXPROPLEN, B_FALSE) != 0 ||
872 strcmp(shareopts, "off") == 0)
873 continue;
874 ret = zfs_init_libshare_arg(hdl, service, zhp);
875 if (ret != SA_OK) {
876 (void) zfs_error_fmt(hdl, EZFS_SHARENFSFAILED,
877 dgettext(TEXT_DOMAIN, "cannot share '%s': %s"),
878 zfs_get_name(zhp), _sa_errorstr != NULL ?
879 _sa_errorstr(ret) : "");
880 return (-1);
881 }
882
883 /*
884 * If the 'zoned' property is set, then zfs_is_mountable()
885 * will have already bailed out if we are in the global zone.
886 * But local zones cannot be NFS servers, so we ignore it for
887 * local zones as well.
888 */
889 if (zfs_prop_get_int(zhp, ZFS_PROP_ZONED))
890 continue;
891
892 share = zfs_sa_find_share(hdl->libzfs_sharehdl, mountpoint);
893 if (share == NULL) {
894 /*
895 * This may be a new file system that was just
896 * created so isn't in the internal cache
897 * (second time through). Rather than
898 * reloading the entire configuration, we can
899 * assume ZFS has done the checking and it is
900 * safe to add this to the internal
901 * configuration.
902 */
903 if (_sa_zfs_process_share(hdl->libzfs_sharehdl,
904 NULL, NULL, mountpoint,
905 proto_table[*curr_proto].p_name, sourcetype,
906 shareopts, sourcestr, zhp->zfs_name) != SA_OK) {
907 (void) zfs_error_fmt(hdl,
908 proto_table[*curr_proto].p_share_err,
909 dgettext(TEXT_DOMAIN, "cannot share '%s'"),
910 zfs_get_name(zhp));
911 return (-1);
912 }
913 share = zfs_sa_find_share(hdl->libzfs_sharehdl,
914 mountpoint);
915 }
916 if (share != NULL) {
917 int err;
918 err = zfs_sa_enable_share(share,
919 proto_table[*curr_proto].p_name);
920 if (err != SA_OK) {
921 (void) zfs_error_fmt(hdl,
922 proto_table[*curr_proto].p_share_err,
923 dgettext(TEXT_DOMAIN, "cannot share '%s'"),
924 zfs_get_name(zhp));
925 return (-1);
926 }
927 } else {
928 (void) zfs_error_fmt(hdl,
929 proto_table[*curr_proto].p_share_err,
930 dgettext(TEXT_DOMAIN, "cannot share '%s'"),
931 zfs_get_name(zhp));
932 return (-1);
933 }
934
935 }
936 return (0);
937 }
938
939
940 int
941 zfs_share_nfs(zfs_handle_t *zhp)
942 {
943 return (zfs_share_proto(zhp, nfs_only));
944 }
945
946 int
947 zfs_share_smb(zfs_handle_t *zhp)
948 {
949 return (zfs_share_proto(zhp, smb_only));
950 }
951
952 int
953 zfs_shareall(zfs_handle_t *zhp)
954 {
955 return (zfs_share_proto(zhp, share_all_proto));
956 }
957
958 /*
959 * Unshare a filesystem by mountpoint.
960 */
961 static int
962 unshare_one(libzfs_handle_t *hdl, const char *name, const char *mountpoint,
963 zfs_share_proto_t proto)
964 {
965 sa_share_t share;
966 int err;
967 char *mntpt;
968 int service = SA_INIT_ONE_SHARE_FROM_NAME;
969
970 /*
971 * Mountpoint could get trashed if libshare calls getmntany
972 * which it does during API initialization, so strdup the
973 * value.
974 */
975 mntpt = zfs_strdup(hdl, mountpoint);
976
977 /*
978 * Function may be called in a loop from higher up stack, with libshare
979 * initialized for multiple shares (SA_INIT_SHARE_API_SELECTIVE).
980 * zfs_init_libshare_arg will refresh the handle's cache if necessary.
981 * In this case we do not want to switch to per share initialization.
982 * Specify SA_INIT_SHARE_API to do full refresh, if refresh required.
983 */
984 if ((hdl->libzfs_sharehdl != NULL) && (_sa_service != NULL) &&
985 (_sa_service(hdl->libzfs_sharehdl) ==
986 SA_INIT_SHARE_API_SELECTIVE)) {
987 service = SA_INIT_SHARE_API;
988 }
989
990 err = zfs_init_libshare_arg(hdl, service, (void *)name);
991 if (err != SA_OK) {
992 free(mntpt); /* don't need the copy anymore */
993 return (zfs_error_fmt(hdl, proto_table[proto].p_unshare_err,
994 dgettext(TEXT_DOMAIN, "cannot unshare '%s': %s"),
995 name, _sa_errorstr(err)));
996 }
997
998 share = zfs_sa_find_share(hdl->libzfs_sharehdl, mntpt);
999 free(mntpt); /* don't need the copy anymore */
1000
1001 if (share != NULL) {
1002 err = zfs_sa_disable_share(share, proto_table[proto].p_name);
1003 if (err != SA_OK) {
1004 return (zfs_error_fmt(hdl,
1005 proto_table[proto].p_unshare_err,
1006 dgettext(TEXT_DOMAIN, "cannot unshare '%s': %s"),
1007 name, _sa_errorstr(err)));
1008 }
1009 } else {
1010 return (zfs_error_fmt(hdl, proto_table[proto].p_unshare_err,
1011 dgettext(TEXT_DOMAIN, "cannot unshare '%s': not found"),
1012 name));
1013 }
1014 return (0);
1015 }
1016
1017 /*
1018 * Unshare the given filesystem.
1019 */
1020 int
1021 zfs_unshare_proto(zfs_handle_t *zhp, const char *mountpoint,
1022 zfs_share_proto_t *proto)
1023 {
1024 libzfs_handle_t *hdl = zhp->zfs_hdl;
1025 struct mnttab entry;
1026 char *mntpt = NULL;
1027
1028 /* check to see if need to unmount the filesystem */
1029 rewind(zhp->zfs_hdl->libzfs_mnttab);
1030 if (mountpoint != NULL)
1031 mountpoint = mntpt = zfs_strdup(hdl, mountpoint);
1032
1033 if (mountpoint != NULL || ((zfs_get_type(zhp) == ZFS_TYPE_FILESYSTEM) &&
1034 libzfs_mnttab_find(hdl, zfs_get_name(zhp), &entry) == 0)) {
1035 zfs_share_proto_t *curr_proto;
1036
1037 if (mountpoint == NULL)
1038 mntpt = zfs_strdup(zhp->zfs_hdl, entry.mnt_mountp);
1039
1040 for (curr_proto = proto; *curr_proto != PROTO_END;
1041 curr_proto++) {
1042
1043 if (is_shared(hdl, mntpt, *curr_proto) &&
1044 unshare_one(hdl, zhp->zfs_name,
1045 mntpt, *curr_proto) != 0) {
1046 if (mntpt != NULL)
1047 free(mntpt);
1048 return (-1);
1049 }
1050 }
1051 }
1052 if (mntpt != NULL)
1053 free(mntpt);
1054
1055 return (0);
1056 }
1057
1058 int
1059 zfs_unshare_nfs(zfs_handle_t *zhp, const char *mountpoint)
1060 {
1061 return (zfs_unshare_proto(zhp, mountpoint, nfs_only));
1062 }
1063
1064 int
1065 zfs_unshare_smb(zfs_handle_t *zhp, const char *mountpoint)
1066 {
1067 return (zfs_unshare_proto(zhp, mountpoint, smb_only));
1068 }
1069
1070 /*
1071 * Same as zfs_unmountall(), but for NFS and SMB unshares.
1072 */
1073 int
1074 zfs_unshareall_proto(zfs_handle_t *zhp, zfs_share_proto_t *proto)
1075 {
1076 prop_changelist_t *clp;
1077 int ret;
1078
1079 clp = changelist_gather(zhp, ZFS_PROP_SHARENFS, 0, 0);
1080 if (clp == NULL)
1081 return (-1);
1082
1083 ret = changelist_unshare(clp, proto);
1084 changelist_free(clp);
1085
1086 return (ret);
1087 }
1088
1089 int
1090 zfs_unshareall_nfs(zfs_handle_t *zhp)
1091 {
1092 return (zfs_unshareall_proto(zhp, nfs_only));
1093 }
1094
1095 int
1096 zfs_unshareall_smb(zfs_handle_t *zhp)
1097 {
1098 return (zfs_unshareall_proto(zhp, smb_only));
1099 }
1100
1101 int
1102 zfs_unshareall(zfs_handle_t *zhp)
1103 {
1104 return (zfs_unshareall_proto(zhp, share_all_proto));
1105 }
1106
1107 int
1108 zfs_unshareall_bypath(zfs_handle_t *zhp, const char *mountpoint)
1109 {
1110 return (zfs_unshare_proto(zhp, mountpoint, share_all_proto));
1111 }
1112
1113 /*
1114 * Remove the mountpoint associated with the current dataset, if necessary.
1115 * We only remove the underlying directory if:
1116 *
1117 * - The mountpoint is not 'none' or 'legacy'
1118 * - The mountpoint is non-empty
1119 * - The mountpoint is the default or inherited
1120 * - The 'zoned' property is set, or we're in a local zone
1121 *
1122 * Any other directories we leave alone.
1123 */
1124 void
1125 remove_mountpoint(zfs_handle_t *zhp)
1126 {
1127 char mountpoint[ZFS_MAXPROPLEN];
1128 zprop_source_t source;
1129
1130 if (!zfs_is_mountable(zhp, mountpoint, sizeof (mountpoint),
1131 &source))
1132 return;
1133
1134 if (source == ZPROP_SRC_DEFAULT ||
1135 source == ZPROP_SRC_INHERITED) {
1136 /*
1137 * Try to remove the directory, silently ignoring any errors.
1138 * The filesystem may have since been removed or moved around,
1139 * and this error isn't really useful to the administrator in
1140 * any way.
1141 */
1142 (void) rmdir(mountpoint);
1143 }
1144 }
1145
1146 /*
1147 * Add the given zfs handle to the cb_handles array, dynamically reallocating
1148 * the array if it is out of space.
1149 */
1150 void
1151 libzfs_add_handle(get_all_cb_t *cbp, zfs_handle_t *zhp)
1152 {
1153 if (cbp->cb_alloc == cbp->cb_used) {
1154 size_t newsz;
1155 zfs_handle_t **newhandles;
1156
1157 newsz = cbp->cb_alloc != 0 ? cbp->cb_alloc * 2 : 64;
1158 newhandles = zfs_realloc(zhp->zfs_hdl,
1159 cbp->cb_handles, cbp->cb_alloc * sizeof (zfs_handle_t *),
1160 newsz * sizeof (zfs_handle_t *));
1161 cbp->cb_handles = newhandles;
1162 cbp->cb_alloc = newsz;
1163 }
1164 cbp->cb_handles[cbp->cb_used++] = zhp;
1165 }
1166
1167 /*
1168 * Recursive helper function used during file system enumeration
1169 */
1170 static int
1171 zfs_iter_cb(zfs_handle_t *zhp, void *data)
1172 {
1173 get_all_cb_t *cbp = data;
1174
1175 if (!(zfs_get_type(zhp) & ZFS_TYPE_FILESYSTEM)) {
1176 zfs_close(zhp);
1177 return (0);
1178 }
1179
1180 if (zfs_prop_get_int(zhp, ZFS_PROP_CANMOUNT) == ZFS_CANMOUNT_NOAUTO) {
1181 zfs_close(zhp);
1182 return (0);
1183 }
1184
1185 if (zfs_prop_get_int(zhp, ZFS_PROP_KEYSTATUS) ==
1186 ZFS_KEYSTATUS_UNAVAILABLE) {
1187 zfs_close(zhp);
1188 return (0);
1189 }
1190
1191 /*
1192 * If this filesystem is inconsistent and has a receive resume
1193 * token, we can not mount it.
1194 */
1195 if (zfs_prop_get_int(zhp, ZFS_PROP_INCONSISTENT) &&
1196 zfs_prop_get(zhp, ZFS_PROP_RECEIVE_RESUME_TOKEN,
1197 NULL, 0, NULL, NULL, 0, B_TRUE) == 0) {
1198 zfs_close(zhp);
1199 return (0);
1200 }
1201
1202 libzfs_add_handle(cbp, zhp);
1203 if (zfs_iter_filesystems(zhp, zfs_iter_cb, cbp) != 0) {
1204 zfs_close(zhp);
1205 return (-1);
1206 }
1207 return (0);
1208 }
1209
1210 /*
1211 * Sort comparator that compares two mountpoint paths. We sort these paths so
1212 * that subdirectories immediately follow their parents. This means that we
1213 * effectively treat the '/' character as the lowest value non-nul char.
1214 * Since filesystems from non-global zones can have the same mountpoint
1215 * as other filesystems, the comparator sorts global zone filesystems to
1216 * the top of the list. This means that the global zone will traverse the
1217 * filesystem list in the correct order and can stop when it sees the
1218 * first zoned filesystem. In a non-global zone, only the delegated
1219 * filesystems are seen.
1220 *
1221 * An example sorted list using this comparator would look like:
1222 *
1223 * /foo
1224 * /foo/bar
1225 * /foo/bar/baz
1226 * /foo/baz
1227 * /foo.bar
1228 * /foo (NGZ1)
1229 * /foo (NGZ2)
1230 *
1231 * The mounting code depends on this ordering to deterministically iterate
1232 * over filesystems in order to spawn parallel mount tasks.
1233 */
1234 static int
1235 mountpoint_cmp(const void *arga, const void *argb)
1236 {
1237 zfs_handle_t *const *zap = arga;
1238 zfs_handle_t *za = *zap;
1239 zfs_handle_t *const *zbp = argb;
1240 zfs_handle_t *zb = *zbp;
1241 char mounta[MAXPATHLEN];
1242 char mountb[MAXPATHLEN];
1243 const char *a = mounta;
1244 const char *b = mountb;
1245 boolean_t gota, gotb;
1246 uint64_t zoneda, zonedb;
1247
1248 zoneda = zfs_prop_get_int(za, ZFS_PROP_ZONED);
1249 zonedb = zfs_prop_get_int(zb, ZFS_PROP_ZONED);
1250 if (zoneda && !zonedb)
1251 return (1);
1252 if (!zoneda && zonedb)
1253 return (-1);
1254
1255 gota = (zfs_get_type(za) == ZFS_TYPE_FILESYSTEM);
1256 if (gota) {
1257 verify(zfs_prop_get(za, ZFS_PROP_MOUNTPOINT, mounta,
1258 sizeof (mounta), NULL, NULL, 0, B_FALSE) == 0);
1259 }
1260 gotb = (zfs_get_type(zb) == ZFS_TYPE_FILESYSTEM);
1261 if (gotb) {
1262 verify(zfs_prop_get(zb, ZFS_PROP_MOUNTPOINT, mountb,
1263 sizeof (mountb), NULL, NULL, 0, B_FALSE) == 0);
1264 }
1265
1266 if (gota && gotb) {
1267 while (*a != '\0' && (*a == *b)) {
1268 a++;
1269 b++;
1270 }
1271 if (*a == *b)
1272 return (0);
1273 if (*a == '\0')
1274 return (-1);
1275 if (*b == '\0')
1276 return (1);
1277 if (*a == '/')
1278 return (-1);
1279 if (*b == '/')
1280 return (1);
1281 return (*a < *b ? -1 : *a > *b);
1282 }
1283
1284 if (gota)
1285 return (-1);
1286 if (gotb)
1287 return (1);
1288
1289 /*
1290 * If neither filesystem has a mountpoint, revert to sorting by
1291 * dataset name.
1292 */
1293 return (strcmp(zfs_get_name(za), zfs_get_name(zb)));
1294 }
1295
1296 /*
1297 * Return true if path2 is a child of path1.
1298 */
1299 static boolean_t
1300 libzfs_path_contains(const char *path1, const char *path2)
1301 {
1302 return (strstr(path2, path1) == path2 && path2[strlen(path1)] == '/');
1303 }
1304
1305 /*
1306 * Given a mountpoint specified by idx in the handles array, find the first
1307 * non-descendent of that mountpoint and return its index. Descendant paths
1308 * start with the parent's path. This function relies on the ordering
1309 * enforced by mountpoint_cmp().
1310 */
1311 static int
1312 non_descendant_idx(zfs_handle_t **handles, size_t num_handles, int idx)
1313 {
1314 char parent[ZFS_MAXPROPLEN];
1315 char child[ZFS_MAXPROPLEN];
1316 int i;
1317
1318 verify(zfs_prop_get(handles[idx], ZFS_PROP_MOUNTPOINT, parent,
1319 sizeof (parent), NULL, NULL, 0, B_FALSE) == 0);
1320
1321 for (i = idx + 1; i < num_handles; i++) {
1322 verify(zfs_prop_get(handles[i], ZFS_PROP_MOUNTPOINT, child,
1323 sizeof (child), NULL, NULL, 0, B_FALSE) == 0);
1324 if (!libzfs_path_contains(parent, child))
1325 break;
1326 }
1327 return (i);
1328 }
1329
1330 typedef struct mnt_param {
1331 libzfs_handle_t *mnt_hdl;
1332 zfs_taskq_t *mnt_tq;
1333 zfs_handle_t **mnt_zhps; /* filesystems to mount */
1334 size_t mnt_num_handles;
1335 int mnt_idx; /* Index of selected entry to mount */
1336 zfs_iter_f mnt_func;
1337 void *mnt_data;
1338 } mnt_param_t;
1339
1340 /*
1341 * Allocate and populate the parameter struct for mount function, and
1342 * schedule mounting of the entry selected by idx.
1343 */
1344 static void
1345 zfs_dispatch_mount(libzfs_handle_t *hdl, zfs_handle_t **handles,
1346 size_t num_handles, int idx, zfs_iter_f func, void *data, zfs_taskq_t *tq)
1347 {
1348 mnt_param_t *mnt_param = zfs_alloc(hdl, sizeof (mnt_param_t));
1349
1350 mnt_param->mnt_hdl = hdl;
1351 mnt_param->mnt_tq = tq;
1352 mnt_param->mnt_zhps = handles;
1353 mnt_param->mnt_num_handles = num_handles;
1354 mnt_param->mnt_idx = idx;
1355 mnt_param->mnt_func = func;
1356 mnt_param->mnt_data = data;
1357
1358 (void) zfs_taskq_dispatch(tq, zfs_mount_task, (void*)mnt_param,
1359 ZFS_TQ_SLEEP);
1360 }
1361
1362 /*
1363 * This is the structure used to keep state of mounting or sharing operations
1364 * during a call to zpool_enable_datasets().
1365 */
1366 typedef struct mount_state {
1367 /*
1368 * ms_mntstatus is set to -1 if any mount fails. While multiple threads
1369 * could update this variable concurrently, no synchronization is
1370 * needed as it's only ever set to -1.
1371 */
1372 int ms_mntstatus;
1373 int ms_mntflags;
1374 const char *ms_mntopts;
1375 } mount_state_t;
1376
1377 static int
1378 zfs_mount_one(zfs_handle_t *zhp, void *arg)
1379 {
1380 mount_state_t *ms = arg;
1381 int ret = 0;
1382
1383 if (zfs_prop_get_int(zhp, ZFS_PROP_KEYSTATUS) ==
1384 ZFS_KEYSTATUS_UNAVAILABLE)
1385 return (0);
1386
1387 if (zfs_mount(zhp, ms->ms_mntopts, ms->ms_mntflags) != 0)
1388 ret = ms->ms_mntstatus = -1;
1389 return (ret);
1390 }
1391
1392 static int
1393 zfs_share_one(zfs_handle_t *zhp, void *arg)
1394 {
1395 mount_state_t *ms = arg;
1396 int ret = 0;
1397
1398 if (zfs_share(zhp) != 0)
1399 ret = ms->ms_mntstatus = -1;
1400 return (ret);
1401 }
1402
1403 /*
1404 * Task queue function to mount one file system. On completion, it finds and
1405 * schedules its children to be mounted. This depends on the sorting done in
1406 * zfs_foreach_mountpoint(). Note that the degenerate case (chain of entries
1407 * each descending from the previous) will have no parallelism since we always
1408 * have to wait for the parent to finish mounting before we can schedule
1409 * its children.
1410 */
1411 static void
1412 zfs_mount_task(void *arg)
1413 {
1414 mnt_param_t *mp = arg;
1415 int idx = mp->mnt_idx;
1416 zfs_handle_t **handles = mp->mnt_zhps;
1417 size_t num_handles = mp->mnt_num_handles;
1418 char mountpoint[ZFS_MAXPROPLEN];
1419
1420 verify(zfs_prop_get(handles[idx], ZFS_PROP_MOUNTPOINT, mountpoint,
1421 sizeof (mountpoint), NULL, NULL, 0, B_FALSE) == 0);
1422
1423 if (mp->mnt_func(handles[idx], mp->mnt_data) != 0)
1424 return;
1425
1426 /*
1427 * We dispatch tasks to mount filesystems with mountpoints underneath
1428 * this one. We do this by dispatching the next filesystem with a
1429 * descendant mountpoint of the one we just mounted, then skip all of
1430 * its descendants, dispatch the next descendant mountpoint, and so on.
1431 * The non_descendant_idx() function skips over filesystems that are
1432 * descendants of the filesystem we just dispatched.
1433 */
1434 for (int i = idx + 1; i < num_handles;
1435 i = non_descendant_idx(handles, num_handles, i)) {
1436 char child[ZFS_MAXPROPLEN];
1437 verify(zfs_prop_get(handles[i], ZFS_PROP_MOUNTPOINT,
1438 child, sizeof (child), NULL, NULL, 0, B_FALSE) == 0);
1439
1440 if (!libzfs_path_contains(mountpoint, child))
1441 break; /* not a descendant, return */
1442 zfs_dispatch_mount(mp->mnt_hdl, handles, num_handles, i,
1443 mp->mnt_func, mp->mnt_data, mp->mnt_tq);
1444 }
1445 free(mp);
1446 }
1447
1448 /*
1449 * Issue the func callback for each ZFS handle contained in the handles
1450 * array. This function is used to mount all datasets, and so this function
1451 * guarantees that filesystems for parent mountpoints are called before their
1452 * children. As such, before issuing any callbacks, we first sort the array
1453 * of handles by mountpoint.
1454 *
1455 * Callbacks are issued in one of two ways:
1456 *
1457 * 1. Sequentially: If the parallel argument is B_FALSE or the ZFS_SERIAL_MOUNT
1458 * environment variable is set, then we issue callbacks sequentially.
1459 *
1460 * 2. In parallel: If the parallel argument is B_TRUE and the ZFS_SERIAL_MOUNT
1461 * environment variable is not set, then we use a taskq to dispatch threads
1462 * to mount filesystems is parallel. This function dispatches tasks to mount
1463 * the filesystems at the top-level mountpoints, and these tasks in turn
1464 * are responsible for recursively mounting filesystems in their children
1465 * mountpoints.
1466 */
1467 void
1468 zfs_foreach_mountpoint(libzfs_handle_t *hdl, zfs_handle_t **handles,
1469 size_t num_handles, zfs_iter_f func, void *data, boolean_t parallel)
1470 {
1471 zoneid_t zoneid = getzoneid();
1472
1473 /*
1474 * The ZFS_SERIAL_MOUNT environment variable is an undocumented
1475 * variable that can be used as a convenience to do a/b comparison
1476 * of serial vs. parallel mounting.
1477 */
1478 boolean_t serial_mount = !parallel ||
1479 (getenv("ZFS_SERIAL_MOUNT") != NULL);
1480
1481 /*
1482 * Sort the datasets by mountpoint. See mountpoint_cmp for details
1483 * of how these are sorted.
1484 */
1485 qsort(handles, num_handles, sizeof (zfs_handle_t *), mountpoint_cmp);
1486
1487 if (serial_mount) {
1488 for (int i = 0; i < num_handles; i++) {
1489 func(handles[i], data);
1490 }
1491 return;
1492 }
1493
1494 /*
1495 * Issue the callback function for each dataset using a parallel
1496 * algorithm that uses a taskq to manage threads.
1497 */
1498 zfs_taskq_t *tq = zfs_taskq_create("mount_taskq", mount_tq_nthr, 0,
1499 mount_tq_nthr, mount_tq_nthr, ZFS_TASKQ_PREPOPULATE);
1500
1501 /*
1502 * There may be multiple "top level" mountpoints outside of the pool's
1503 * root mountpoint, e.g.: /foo /bar. Dispatch a mount task for each of
1504 * these.
1505 */
1506 for (int i = 0; i < num_handles;
1507 i = non_descendant_idx(handles, num_handles, i)) {
1508 /*
1509 * Since the mountpoints have been sorted so that the zoned
1510 * filesystems are at the end, a zoned filesystem seen from
1511 * the global zone means that we're done.
1512 */
1513 if (zoneid == GLOBAL_ZONEID &&
1514 zfs_prop_get_int(handles[i], ZFS_PROP_ZONED))
1515 break;
1516 zfs_dispatch_mount(hdl, handles, num_handles, i, func, data,
1517 tq);
1518 }
1519
1520 zfs_taskq_wait(tq); /* wait for all scheduled mounts to complete */
1521 zfs_taskq_destroy(tq);
1522 }
1523
1524 /*
1525 * Mount and share all datasets within the given pool. This assumes that no
1526 * datasets within the pool are currently mounted.
1527 */
1528 #pragma weak zpool_mount_datasets = zpool_enable_datasets
1529 int
1530 zpool_enable_datasets(zpool_handle_t *zhp, const char *mntopts, int flags)
1531 {
1532 get_all_cb_t cb = { 0 };
1533 mount_state_t ms = { 0 };
1534 zfs_handle_t *zfsp;
1535 sa_init_selective_arg_t sharearg;
1536 int ret = 0;
1537
1538 if ((zfsp = zfs_open(zhp->zpool_hdl, zhp->zpool_name,
1539 ZFS_TYPE_DATASET)) == NULL)
1540 goto out;
1541
1542
1543 /*
1544 * Gather all non-snapshot datasets within the pool. Start by adding
1545 * the root filesystem for this pool to the list, and then iterate
1546 * over all child filesystems.
1547 */
1548 libzfs_add_handle(&cb, zfsp);
1549 if (zfs_iter_filesystems(zfsp, zfs_iter_cb, &cb) != 0)
1550 goto out;
1551
1552 ms.ms_mntopts = mntopts;
1553 ms.ms_mntflags = flags;
1554 zfs_foreach_mountpoint(zhp->zpool_hdl, cb.cb_handles, cb.cb_used,
1555 zfs_mount_one, &ms, B_TRUE);
1556 if (ms.ms_mntstatus != 0)
1557 ret = ms.ms_mntstatus;
1558
1559 /*
1560 * Initialize libshare SA_INIT_SHARE_API_SELECTIVE here
1561 * to avoid unnecessary load/unload of the libshare API
1562 * per shared dataset downstream.
1563 */
1564 sharearg.zhandle_arr = cb.cb_handles;
1565 sharearg.zhandle_len = cb.cb_used;
1566 if ((ret = zfs_init_libshare_arg(zhp->zpool_hdl,
1567 SA_INIT_SHARE_API_SELECTIVE, &sharearg)) != 0)
1568 goto out;
1569
1570 ms.ms_mntstatus = 0;
1571 zfs_foreach_mountpoint(zhp->zpool_hdl, cb.cb_handles, cb.cb_used,
1572 zfs_share_one, &ms, B_FALSE);
1573 if (ms.ms_mntstatus != 0)
1574 ret = ms.ms_mntstatus;
1575
1576 out:
1577 for (int i = 0; i < cb.cb_used; i++)
1578 zfs_close(cb.cb_handles[i]);
1579 free(cb.cb_handles);
1580
1581 return (ret);
1582 }
1583
1584 static int
1585 mountpoint_compare(const void *a, const void *b)
1586 {
1587 const char *mounta = *((char **)a);
1588 const char *mountb = *((char **)b);
1589
1590 return (strcmp(mountb, mounta));
1591 }
1592
1593 /* alias for 2002/240 */
1594 #pragma weak zpool_unmount_datasets = zpool_disable_datasets
1595 /*
1596 * Unshare and unmount all datasets within the given pool. We don't want to
1597 * rely on traversing the DSL to discover the filesystems within the pool,
1598 * because this may be expensive (if not all of them are mounted), and can fail
1599 * arbitrarily (on I/O error, for example). Instead, we walk /etc/mnttab and
1600 * gather all the filesystems that are currently mounted.
1601 */
1602 int
1603 zpool_disable_datasets(zpool_handle_t *zhp, boolean_t force)
1604 {
1605 int used, alloc;
1606 struct mnttab entry;
1607 size_t namelen;
1608 char **mountpoints = NULL;
1609 zfs_handle_t **datasets = NULL;
1610 libzfs_handle_t *hdl = zhp->zpool_hdl;
1611 int i;
1612 int ret = -1;
1613 int flags = (force ? MS_FORCE : 0);
1614 sa_init_selective_arg_t sharearg;
1615
1616 namelen = strlen(zhp->zpool_name);
1617
1618 rewind(hdl->libzfs_mnttab);
1619 used = alloc = 0;
1620 while (getmntent(hdl->libzfs_mnttab, &entry) == 0) {
1621 /*
1622 * Ignore non-ZFS entries.
1623 */
1624 if (entry.mnt_fstype == NULL ||
1625 strcmp(entry.mnt_fstype, MNTTYPE_ZFS) != 0)
1626 continue;
1627
1628 /*
1629 * Ignore filesystems not within this pool.
1630 */
1631 if (entry.mnt_mountp == NULL ||
1632 strncmp(entry.mnt_special, zhp->zpool_name, namelen) != 0 ||
1633 (entry.mnt_special[namelen] != '/' &&
1634 entry.mnt_special[namelen] != '\0'))
1635 continue;
1636
1637 /*
1638 * At this point we've found a filesystem within our pool. Add
1639 * it to our growing list.
1640 */
1641 if (used == alloc) {
1642 if (alloc == 0) {
1643 if ((mountpoints = zfs_alloc(hdl,
1644 8 * sizeof (void *))) == NULL)
1645 goto out;
1646
1647 if ((datasets = zfs_alloc(hdl,
1648 8 * sizeof (void *))) == NULL)
1649 goto out;
1650
1651 alloc = 8;
1652 } else {
1653 void *ptr;
1654
1655 if ((ptr = zfs_realloc(hdl, mountpoints,
1656 alloc * sizeof (void *),
1657 alloc * 2 * sizeof (void *))) == NULL)
1658 goto out;
1659 mountpoints = ptr;
1660
1661 if ((ptr = zfs_realloc(hdl, datasets,
1662 alloc * sizeof (void *),
1663 alloc * 2 * sizeof (void *))) == NULL)
1664 goto out;
1665 datasets = ptr;
1666
1667 alloc *= 2;
1668 }
1669 }
1670
1671 if ((mountpoints[used] = zfs_strdup(hdl,
1672 entry.mnt_mountp)) == NULL)
1673 goto out;
1674
1675 /*
1676 * This is allowed to fail, in case there is some I/O error. It
1677 * is only used to determine if we need to remove the underlying
1678 * mountpoint, so failure is not fatal.
1679 */
1680 datasets[used] = make_dataset_handle(hdl, entry.mnt_special);
1681
1682 used++;
1683 }
1684
1685 /*
1686 * At this point, we have the entire list of filesystems, so sort it by
1687 * mountpoint.
1688 */
1689 sharearg.zhandle_arr = datasets;
1690 sharearg.zhandle_len = used;
1691 ret = zfs_init_libshare_arg(hdl, SA_INIT_SHARE_API_SELECTIVE,
1692 &sharearg);
1693 if (ret != 0)
1694 goto out;
1695 qsort(mountpoints, used, sizeof (char *), mountpoint_compare);
1696
1697 /*
1698 * Walk through and first unshare everything.
1699 */
1700 for (i = 0; i < used; i++) {
1701 zfs_share_proto_t *curr_proto;
1702 for (curr_proto = share_all_proto; *curr_proto != PROTO_END;
1703 curr_proto++) {
1704 if (is_shared(hdl, mountpoints[i], *curr_proto) &&
1705 unshare_one(hdl, mountpoints[i],
1706 mountpoints[i], *curr_proto) != 0)
1707 goto out;
1708 }
1709 }
1710
1711 /*
1712 * Now unmount everything, removing the underlying directories as
1713 * appropriate.
1714 */
1715 for (i = 0; i < used; i++) {
1716 if (unmount_one(hdl, mountpoints[i], flags) != 0)
1717 goto out;
1718 }
1719
1720 for (i = 0; i < used; i++) {
1721 if (datasets[i])
1722 remove_mountpoint(datasets[i]);
1723 }
1724
1725 ret = 0;
1726 out:
1727 for (i = 0; i < used; i++) {
1728 if (datasets[i])
1729 zfs_close(datasets[i]);
1730 free(mountpoints[i]);
1731 }
1732 free(datasets);
1733 free(mountpoints);
1734
1735 return (ret);
1736 }