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 (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
24 */
25
26 /*
27 * Copyright 2013 Nexenta Systems, Inc. All rights reserved.
28 */
29
30 /*
31 * System includes
32 */
33 #include <assert.h>
34 #include <libintl.h>
35 #include <libnvpair.h>
36 #include <libzfs.h>
37 #include <stdio.h>
38 #include <stdlib.h>
39 #include <string.h>
40 #include <sys/types.h>
41 #include <sys/stat.h>
42 #include <unistd.h>
43
44 #include <libbe.h>
45 #include <libbe_priv.h>
46
47 /* Private function prototypes */
48 static int be_rollback_check_callback(zfs_handle_t *, void *);
49 static int be_rollback_callback(zfs_handle_t *, void *);
50
51
52 /* ******************************************************************** */
53 /* Public Functions */
54 /* ******************************************************************** */
55
56 /*
57 * Function: be_create_snapshot
58 * Description: Creates a recursive snapshot of all the datasets within a BE.
59 * If the name of the BE to snapshot is not provided, it assumes
60 * we're snapshotting the currently running BE. If the snapshot
61 * name is not provided it creates an auto named snapshot, which
62 * will be returned to the caller upon success.
63 * Parameters:
64 * be_attrs - pointer to nvlist_t of attributes being passed in.
65 * The following attributes are used by this function:
66 *
67 * BE_ATTR_ORIG_BE_NAME *optional
68 * BE_ATTR_SNAP_NAME *optional
69 * BE_ATTR_POLICY *optional
70 *
71 * If the BE_ATTR_SNAP_NAME was not passed in, upon
72 * successful BE snapshot creation, the following
73 * attribute value will be returned to the caller by
74 * setting it in the be_attrs parameter passed in:
75 *
76 * BE_ATTR_SNAP_NAME
77 *
78 * Return:
79 * BE_SUCCESS - Success
80 * be_errno_t - Failure
81 * Scope:
82 * Public
83 */
84 int
85 be_create_snapshot(nvlist_t *be_attrs)
86 {
87 char *be_name = NULL;
88 char *snap_name = NULL;
89 char *policy = NULL;
90 boolean_t autoname = B_FALSE;
91 int ret = BE_SUCCESS;
92
93 /* Initialize libzfs handle */
94 if (!be_zfs_init())
95 return (BE_ERR_INIT);
96
97 /* Get original BE name if one was provided */
98 if (nvlist_lookup_pairs(be_attrs, NV_FLAG_NOENTOK,
99 BE_ATTR_ORIG_BE_NAME, DATA_TYPE_STRING, &be_name, NULL) != 0) {
100 be_print_err(gettext("be_create_snapshot: failed to "
101 "lookup BE_ATTR_ORIG_BE_NAME attribute\n"));
102 be_zfs_fini();
103 return (BE_ERR_INVAL);
104 }
105
106 /* Validate original BE name if one was provided */
107 if (be_name != NULL && !be_valid_be_name(be_name)) {
108 be_print_err(gettext("be_create_snapshot: "
109 "invalid BE name %s\n"), be_name);
110 be_zfs_fini();
111 return (BE_ERR_INVAL);
112 }
113
114 /* Get snapshot name to create if one was provided */
115 if (nvlist_lookup_pairs(be_attrs, NV_FLAG_NOENTOK,
116 BE_ATTR_SNAP_NAME, DATA_TYPE_STRING, &snap_name, NULL) != 0) {
117 be_print_err(gettext("be_create_snapshot: "
118 "failed to lookup BE_ATTR_SNAP_NAME attribute\n"));
119 be_zfs_fini();
120 return (BE_ERR_INVAL);
121 }
122
123 /* Get BE policy to create this snapshot under */
124 if (nvlist_lookup_pairs(be_attrs, NV_FLAG_NOENTOK,
125 BE_ATTR_POLICY, DATA_TYPE_STRING, &policy, NULL) != 0) {
126 be_print_err(gettext("be_create_snapshot: "
127 "failed to lookup BE_ATTR_POLICY attribute\n"));
128 be_zfs_fini();
129 return (BE_ERR_INVAL);
130 }
131
132 /*
133 * If no snap_name ws provided, we're going to create an
134 * auto named snapshot. Set flag so that we know to pass
135 * the auto named snapshot to the caller later.
136 */
137 if (snap_name == NULL)
138 autoname = B_TRUE;
139
140 if ((ret = _be_create_snapshot(be_name, &snap_name, policy))
141 == BE_SUCCESS) {
142 if (autoname == B_TRUE) {
143 /*
144 * Set auto named snapshot name in the
145 * nvlist passed in by the caller.
146 */
147 if (nvlist_add_string(be_attrs, BE_ATTR_SNAP_NAME,
148 snap_name) != 0) {
149 be_print_err(gettext("be_create_snapshot: "
150 "failed to add auto snap name (%s) to "
151 "be_attrs\n"), snap_name);
152 ret = BE_ERR_NOMEM;
153 }
154 }
155 }
156
157 be_zfs_fini();
158
159 return (ret);
160 }
161
162 /*
163 * Function: be_destroy_snapshot
164 * Description: Iterates through all the datasets of the BE and deletes
165 * the snapshots of each one with the specified name. If the
166 * BE name is not provided, it assumes we're operating on the
167 * currently running BE. The name of the snapshot name to
168 * destroy must be provided.
169 * Parameters:
170 * be_attrs - pointer to nvlist_t of attributes being passed in.
171 * The following attribute values are used by this
172 * function:
173 *
174 * BE_ATTR_ORIG_BE_NAME *optional
175 * BE_ATTR_SNAP_NAME *required
176 * Return:
177 * BE_SUCCESS - Success
178 * be_errno_t - Failure
179 * Scope:
180 * Public
181 */
182 int
183 be_destroy_snapshot(nvlist_t *be_attrs)
184 {
185 char *be_name = NULL;
186 char *snap_name = NULL;
187 int ret = BE_SUCCESS;
188
189 /* Initialize libzfs handle */
190 if (!be_zfs_init())
191 return (BE_ERR_INIT);
192
193 /* Get original BE name if one was provided */
194 if (nvlist_lookup_pairs(be_attrs, NV_FLAG_NOENTOK,
195 BE_ATTR_ORIG_BE_NAME, DATA_TYPE_STRING, &be_name, NULL) != 0) {
196 be_print_err(gettext("be_destroy_snapshot: "
197 "failed to lookup BE_ATTR_ORIG_BE_NAME attribute\n"));
198 return (BE_ERR_INVAL);
199 }
200
201 /* Validate original BE name if one was provided */
202 if (be_name != NULL && !be_valid_be_name(be_name)) {
203 be_print_err(gettext("be_destroy_snapshot: "
204 "invalid BE name %s\n"), be_name);
205 return (BE_ERR_INVAL);
206 }
207
208 /* Get snapshot name to destroy */
209 if (nvlist_lookup_string(be_attrs, BE_ATTR_SNAP_NAME, &snap_name)
210 != 0) {
211 be_print_err(gettext("be_destroy_snapshot: "
212 "failed to lookup BE_ATTR_SNAP_NAME attribute.\n"));
213 return (BE_ERR_INVAL);
214 }
215
216 ret = _be_destroy_snapshot(be_name, snap_name);
217
218 be_zfs_fini();
219
220 return (ret);
221 }
222
223 /*
224 * Function: be_rollback
225 * Description: Rolls back a BE and all of its children datasets to the
226 * named snapshot. All of the BE's datasets must have the
227 * named snapshot for this function to succeed. If the name
228 * of the BE is not passed in, this function assumes we're
229 * operating on the currently booted live BE.
230 *
231 * Note - This function does not check if the BE has any
232 * younger snapshots than the one we're trying to rollback to.
233 * If it does, then those younger snapshots and their dependent
234 * clone file systems will get destroyed in the process of
235 * rolling back.
236 *
237 * Parameters:
238 * be_attrs - pointer to nvlist_t of attributes being passed in.
239 * The following attributes are used by this function:
240 *
241 * BE_ATTR_ORIG_BE_NAME *optional
242 * BE_ATTR_SNAP_NAME *required
243 *
244 * Returns:
245 * BE_SUCCESS - Success
246 * be_errno_t - Failure
247 * Scope:
248 * Public
249 */
250 int
251 be_rollback(nvlist_t *be_attrs)
252 {
253 be_transaction_data_t bt = { 0 };
254 zfs_handle_t *zhp = NULL;
255 zpool_handle_t *zphp;
256 char obe_root_ds[MAXPATHLEN];
257 char *obe_name = NULL;
258 int zret = 0, ret = BE_SUCCESS;
259 struct be_defaults be_defaults;
260
261 /* Initialize libzfs handle */
262 if (!be_zfs_init())
263 return (BE_ERR_INIT);
264
265 if ((ret = be_find_current_be(&bt)) != BE_SUCCESS) {
266 return (ret);
267 }
268
269 /* Get original BE name if one was provided */
270 if (nvlist_lookup_pairs(be_attrs, NV_FLAG_NOENTOK,
271 BE_ATTR_ORIG_BE_NAME, DATA_TYPE_STRING, &obe_name, NULL) != 0) {
272 be_print_err(gettext("be_rollback: "
273 "failed to lookup BE_ATTR_ORIG_BE_NAME attribute\n"));
274 return (BE_ERR_INVAL);
275 }
276
277 be_get_defaults(&be_defaults);
278
279 /* If original BE name not provided, use current BE */
280 if (obe_name != NULL) {
281 bt.obe_name = obe_name;
282 /* Validate original BE name */
283 if (!be_valid_be_name(bt.obe_name)) {
284 be_print_err(gettext("be_rollback: "
285 "invalid BE name %s\n"), bt.obe_name);
286 return (BE_ERR_INVAL);
287 }
288 }
289
290 /* Get snapshot name to rollback to */
291 if (nvlist_lookup_string(be_attrs, BE_ATTR_SNAP_NAME, &bt.obe_snap_name)
292 != 0) {
293 be_print_err(gettext("be_rollback: "
294 "failed to lookup BE_ATTR_SNAP_NAME attribute.\n"));
295 return (BE_ERR_INVAL);
296 }
297
298 if (be_defaults.be_deflt_rpool_container) {
299 if ((zphp = zpool_open(g_zfs, bt.obe_zpool)) == NULL) {
300 be_print_err(gettext("be_rollback: failed to "
301 "open rpool (%s): %s\n"), bt.obe_zpool,
302 libzfs_error_description(g_zfs));
303 return (zfs_err_to_be_err(g_zfs));
304 }
305 zret = be_find_zpool_callback(zphp, &bt);
306 } else {
307 /* Find which zpool obe_name lives in */
308 if ((zret = zpool_iter(g_zfs, be_find_zpool_callback, &bt)) ==
309 0) {
310 be_print_err(gettext("be_rollback: "
311 "failed to find zpool for BE (%s)\n"), bt.obe_name);
312 return (BE_ERR_BE_NOENT);
313 } else if (zret < 0) {
314 be_print_err(gettext("be_rollback: "
315 "zpool_iter failed: %s\n"),
316 libzfs_error_description(g_zfs));
317 return (zfs_err_to_be_err(g_zfs));
318 }
319 }
320
321 /* Generate string for BE's root dataset */
322 be_make_root_ds(bt.obe_zpool, bt.obe_name, obe_root_ds,
323 sizeof (obe_root_ds));
324 bt.obe_root_ds = obe_root_ds;
325
326 if (getzoneid() != GLOBAL_ZONEID) {
327 if (!be_zone_compare_uuids(bt.obe_root_ds)) {
328 be_print_err(gettext("be_rollback: rolling back zone "
329 "root dataset from non-active global BE is not "
330 "supported\n"));
331 return (BE_ERR_NOTSUP);
332 }
333 }
334
335 /* Get handle to BE's root dataset */
336 if ((zhp = zfs_open(g_zfs, bt.obe_root_ds, ZFS_TYPE_DATASET)) == NULL) {
337 be_print_err(gettext("be_rollback: "
338 "failed to open BE root dataset (%s): %s\n"),
339 bt.obe_root_ds, libzfs_error_description(g_zfs));
340 return (zfs_err_to_be_err(g_zfs));
341 }
342
343 /*
344 * Check that snapshot name exists for this BE and all of its
345 * children file systems. This call will end up closing the
346 * zfs handle passed in whether it succeeds or fails.
347 */
348 if ((ret = be_rollback_check_callback(zhp, bt.obe_snap_name)) != 0) {
349 zhp = NULL;
350 return (ret);
351 }
352
353 /* Get handle to BE's root dataset */
354 if ((zhp = zfs_open(g_zfs, bt.obe_root_ds, ZFS_TYPE_DATASET)) == NULL) {
355 be_print_err(gettext("be_rollback: "
356 "failed to open BE root dataset (%s): %s\n"),
357 bt.obe_root_ds, libzfs_error_description(g_zfs));
358 return (zfs_err_to_be_err(g_zfs));
359 }
360
361 /*
362 * Iterate through a BE's datasets and roll them all back to
363 * the specified snapshot. This call will end up closing the
364 * zfs handle passed in whether it succeeds or fails.
365 */
366 if ((ret = be_rollback_callback(zhp, bt.obe_snap_name)) != 0) {
367 zhp = NULL;
368 be_print_err(gettext("be_rollback: "
369 "failed to rollback BE %s to %s\n"), bt.obe_name,
370 bt.obe_snap_name);
371 return (ret);
372 }
373 zhp = NULL;
374 be_zfs_fini();
375 return (BE_SUCCESS);
376 }
377
378
379 /* ******************************************************************** */
380 /* Semi-Private Functions */
381 /* ******************************************************************** */
382
383 /*
384 * Function: _be_create_snapshot
385 * Description: see be_create_snapshot
386 * Parameters:
387 * be_name - The name of the BE that we're taking a snapshot of.
388 * snap_name - The name of the snapshot we're creating. If
389 * snap_name is NULL an auto generated name will be used,
390 * and upon success, will return that name via this
391 * reference pointer. The caller is responsible for
392 * freeing the returned name.
393 * policy - The clean-up policy type. (library wide use only)
394 * Return:
395 * BE_SUCCESS - Success
396 * be_errno_t - Failure
397 * Scope:
398 * Semi-private (library wide use only)
399 */
400 int
401 _be_create_snapshot(char *be_name, char **snap_name, char *policy)
402 {
403 be_transaction_data_t bt = { 0 };
404 zfs_handle_t *zhp = NULL;
405 nvlist_t *ss_props = NULL;
406 char ss[MAXPATHLEN];
407 char root_ds[MAXPATHLEN];
408 int pool_version = 0;
409 int i = 0;
410 int zret = 0, ret = BE_SUCCESS;
411 boolean_t autoname = B_FALSE;
412
413 /* Set parameters in bt structure */
414 bt.obe_name = be_name;
415 bt.obe_snap_name = *snap_name;
416 bt.policy = policy;
417
418 /* If original BE name not supplied, use current BE */
419 if (bt.obe_name == NULL) {
420 if ((ret = be_find_current_be(&bt)) != BE_SUCCESS) {
421 return (ret);
422 }
423 }
424
425 /* Find which zpool obe_name lives in */
426 if ((zret = zpool_iter(g_zfs, be_find_zpool_callback, &bt)) == 0) {
427 be_print_err(gettext("be_create_snapshot: failed to "
428 "find zpool for BE (%s)\n"), bt.obe_name);
429 return (BE_ERR_BE_NOENT);
430 } else if (zret < 0) {
431 be_print_err(gettext("be_create_snapshot: "
432 "zpool_iter failed: %s\n"),
433 libzfs_error_description(g_zfs));
434 return (zfs_err_to_be_err(g_zfs));
435 }
436
437 be_make_root_ds(bt.obe_zpool, bt.obe_name, root_ds,
438 sizeof (root_ds));
439 bt.obe_root_ds = root_ds;
440
441 if (getzoneid() != GLOBAL_ZONEID) {
442 if (!be_zone_compare_uuids(bt.obe_root_ds)) {
443 be_print_err(gettext("be_create_snapshot: creating "
444 "snapshot for the zone root dataset from "
445 "non-active global BE is not "
446 "supported\n"));
447 return (BE_ERR_NOTSUP);
448 }
449 }
450
451 /* If BE policy not specified, use the default policy */
452 if (bt.policy == NULL) {
453 bt.policy = be_default_policy();
454 } else {
455 /* Validate policy type */
456 if (!valid_be_policy(bt.policy)) {
457 be_print_err(gettext("be_create_snapshot: "
458 "invalid BE policy type (%s)\n"), bt.policy);
459 return (BE_ERR_INVAL);
460 }
461 }
462
463 /*
464 * If snapshot name not specified, set auto name flag and
465 * generate auto snapshot name.
466 */
467 if (bt.obe_snap_name == NULL) {
468 autoname = B_TRUE;
469 if ((bt.obe_snap_name = be_auto_snap_name())
470 == NULL) {
471 be_print_err(gettext("be_create_snapshot: "
472 "failed to create auto snapshot name\n"));
473 ret = BE_ERR_AUTONAME;
474 goto done;
475 }
476 }
477
478 /* Generate the name of the snapshot to take. */
479 (void) snprintf(ss, sizeof (ss), "%s@%s", bt.obe_root_ds,
480 bt.obe_snap_name);
481
482 /* Get handle to BE's root dataset */
483 if ((zhp = zfs_open(g_zfs, bt.obe_root_ds, ZFS_TYPE_DATASET))
484 == NULL) {
485 be_print_err(gettext("be_create_snapshot: "
486 "failed to open BE root dataset (%s): %s\n"),
487 bt.obe_root_ds, libzfs_error_description(g_zfs));
488 ret = zfs_err_to_be_err(g_zfs);
489 goto done;
490 }
491
492 /* Get the ZFS pool version of the pool where this dataset resides */
493 if (zfs_spa_version(zhp, &pool_version) != 0) {
494 be_print_err(gettext("be_create_snapshot: failed to "
495 "get ZFS pool version for %s: %s\n"), zfs_get_name(zhp),
496 libzfs_error_description(g_zfs));
497 }
498
499 /*
500 * If ZFS pool version supports snapshot user properties, store
501 * cleanup policy there. Otherwise don't set one - this snapshot
502 * will always inherit the cleanup policy from its parent.
503 */
504 if (getzoneid() == GLOBAL_ZONEID) {
505 if (pool_version >= SPA_VERSION_SNAP_PROPS) {
506 if (nvlist_alloc(&ss_props, NV_UNIQUE_NAME, 0) != 0) {
507 be_print_err(gettext("be_create_snapshot: "
508 "internal error: out of memory\n"));
509 return (BE_ERR_NOMEM);
510 }
511 if (nvlist_add_string(ss_props, BE_POLICY_PROPERTY,
512 bt.policy) != 0) {
513 be_print_err(gettext("be_create_snapshot: "
514 "internal error: out of memory\n"));
515 nvlist_free(ss_props);
516 return (BE_ERR_NOMEM);
517 }
518 } else if (policy != NULL) {
519 /*
520 * If an explicit cleanup policy was requested
521 * by the caller and we don't support it, error out.
522 */
523 be_print_err(gettext("be_create_snapshot: cannot set "
524 "cleanup policy: ZFS pool version is %d\n"),
525 pool_version);
526 return (BE_ERR_NOTSUP);
527 }
528 }
529
530 /* Create the snapshots recursively */
531 if (zfs_snapshot(g_zfs, ss, B_TRUE, ss_props) != 0) {
532 if (!autoname || libzfs_errno(g_zfs) != EZFS_EXISTS) {
533 be_print_err(gettext("be_create_snapshot: "
534 "recursive snapshot of %s failed: %s\n"),
535 ss, libzfs_error_description(g_zfs));
536
537 if (libzfs_errno(g_zfs) == EZFS_EXISTS)
538 ret = BE_ERR_SS_EXISTS;
539 else
540 ret = zfs_err_to_be_err(g_zfs);
541
542 goto done;
543 } else {
544 for (i = 1; i < BE_AUTO_NAME_MAX_TRY; i++) {
545
546 /* Sleep 1 before retrying */
547 (void) sleep(1);
548
549 /* Generate new auto snapshot name. */
550 free(bt.obe_snap_name);
551 if ((bt.obe_snap_name =
552 be_auto_snap_name()) == NULL) {
553 be_print_err(gettext(
554 "be_create_snapshot: failed to "
555 "create auto snapshot name\n"));
556 ret = BE_ERR_AUTONAME;
557 goto done;
558 }
559
560 /* Generate string of the snapshot to take. */
561 (void) snprintf(ss, sizeof (ss), "%s@%s",
562 bt.obe_root_ds, bt.obe_snap_name);
563
564 /* Create the snapshots recursively */
565 if (zfs_snapshot(g_zfs, ss, B_TRUE, ss_props)
566 != 0) {
567 if (libzfs_errno(g_zfs) !=
568 EZFS_EXISTS) {
569 be_print_err(gettext(
570 "be_create_snapshot: "
571 "recursive snapshot of %s "
572 "failed: %s\n"), ss,
573 libzfs_error_description(
574 g_zfs));
575 ret = zfs_err_to_be_err(g_zfs);
576 goto done;
577 }
578 } else {
579 break;
580 }
581 }
582
583 /*
584 * If we exhausted the maximum number of tries,
585 * free the auto snap name and set error.
586 */
587 if (i == BE_AUTO_NAME_MAX_TRY) {
588 be_print_err(gettext("be_create_snapshot: "
589 "failed to create unique auto snapshot "
590 "name\n"));
591 free(bt.obe_snap_name);
592 bt.obe_snap_name = NULL;
593 ret = BE_ERR_AUTONAME;
594 }
595 }
596 }
597
598 /*
599 * If we succeeded in creating an auto named snapshot, store
600 * the name in the nvlist passed in by the caller.
601 */
602 if (autoname && bt.obe_snap_name) {
603 *snap_name = bt.obe_snap_name;
604 }
605
606 done:
607 ZFS_CLOSE(zhp);
608
609 if (ss_props != NULL)
610 nvlist_free(ss_props);
611
612 return (ret);
613 }
614
615 /*
616 * Function: _be_destroy_snapshot
617 * Description: see be_destroy_snapshot
618 * Parameters:
619 * be_name - The name of the BE that the snapshot belongs to.
620 * snap_name - The name of the snapshot we're destroying.
621 * Return:
622 * BE_SUCCESS - Success
623 * be_errno_t - Failure
624 * Scope:
625 * Semi-private (library wide use only)
626 */
627 int
628 _be_destroy_snapshot(char *be_name, char *snap_name)
629 {
630 be_transaction_data_t bt = { 0 };
631 zfs_handle_t *zhp;
632 char ss[MAXPATHLEN];
633 char root_ds[MAXPATHLEN];
634 int err = BE_SUCCESS, ret = BE_SUCCESS;
635
636 /* Make sure we actaully have a snapshot name */
637 if (snap_name == NULL) {
638 be_print_err(gettext("be_destroy_snapshot: "
639 "invalid snapshot name\n"));
640 return (BE_ERR_INVAL);
641 }
642
643 /* Set parameters in bt structure */
644 bt.obe_name = be_name;
645 bt.obe_snap_name = snap_name;
646
647 /* If original BE name not supplied, use current BE */
648 if (bt.obe_name == NULL) {
649 if ((err = be_find_current_be(&bt)) != BE_SUCCESS) {
650 return (err);
651 }
652 }
653
654 /* Find which zpool be_name lives in */
655 if ((ret = zpool_iter(g_zfs, be_find_zpool_callback, &bt)) == 0) {
656 be_print_err(gettext("be_destroy_snapshot: "
657 "failed to find zpool for BE (%s)\n"), bt.obe_name);
658 return (BE_ERR_BE_NOENT);
659 } else if (ret < 0) {
660 be_print_err(gettext("be_destroy_snapshot: "
661 "zpool_iter failed: %s\n"),
662 libzfs_error_description(g_zfs));
663 return (zfs_err_to_be_err(g_zfs));
664 }
665
666 be_make_root_ds(bt.obe_zpool, bt.obe_name, root_ds,
667 sizeof (root_ds));
668 bt.obe_root_ds = root_ds;
669
670 zhp = zfs_open(g_zfs, bt.obe_root_ds, ZFS_TYPE_DATASET);
671 if (zhp == NULL) {
672 /*
673 * The zfs_open failed, return an error.
674 */
675 be_print_err(gettext("be_destroy_snapshot: "
676 "failed to open BE root dataset (%s): %s\n"),
677 bt.obe_root_ds, libzfs_error_description(g_zfs));
678 err = zfs_err_to_be_err(g_zfs);
679 } else {
680 /*
681 * Generate the name of the snapshot to take.
682 */
683 (void) snprintf(ss, sizeof (ss), "%s@%s", bt.obe_name,
684 bt.obe_snap_name);
685
686 /*
687 * destroy the snapshot.
688 */
689 /*
690 * The boolean set to B_FALSE and passed to zfs_destroy_snaps()
691 * tells zfs to process and destroy the snapshots now.
692 * Otherwise the call will potentially return where the
693 * snapshot isn't actually destroyed yet, and ZFS is waiting
694 * until all the references to the snapshot have been
695 * released before actually destroying the snapshot.
696 */
697 if (zfs_destroy_snaps(zhp, bt.obe_snap_name, B_FALSE) != 0) {
698 err = zfs_err_to_be_err(g_zfs);
699 be_print_err(gettext("be_destroy_snapshot: "
700 "failed to destroy snapshot %s: %s\n"), ss,
701 libzfs_error_description(g_zfs));
702 }
703 }
704
705 ZFS_CLOSE(zhp);
706
707 return (err);
708 }
709
710 /* ******************************************************************** */
711 /* Private Functions */
712 /* ******************************************************************** */
713
714 /*
715 * Function: be_rollback_check_callback
716 * Description: Callback function used to iterate through a BE's filesystems
717 * to check if a given snapshot name exists.
718 * Parameters:
719 * zhp - zfs_handle_t pointer to filesystem being processed.
720 * data - name of the snapshot to check for.
721 * Returns:
722 * 0 - Success, snapshot name exists for all filesystems.
723 * be_errno_t - Failure, snapshot name does not exist for all
724 * filesystems.
725 * Scope:
726 * Private
727 */
728 static int
729 be_rollback_check_callback(zfs_handle_t *zhp, void *data)
730 {
731 char *snap_name = data;
732 char ss[MAXPATHLEN];
733 int ret = BE_SUCCESS;
734
735 /* Generate string for this filesystem's snapshot name */
736 (void) snprintf(ss, sizeof (ss), "%s@%s", zfs_get_name(zhp), snap_name);
737
738 /* Check if snapshot exists */
739 if (!zfs_dataset_exists(g_zfs, ss, ZFS_TYPE_SNAPSHOT)) {
740 be_print_err(gettext("be_rollback_check_callback: "
741 "snapshot does not exist %s\n"), ss);
742 ZFS_CLOSE(zhp);
743 return (BE_ERR_SS_NOENT);
744 }
745
746 /* Iterate this dataset's children and check them */
747 if ((ret = zfs_iter_filesystems(zhp, be_rollback_check_callback,
748 snap_name)) != 0) {
749 ZFS_CLOSE(zhp);
750 return (ret);
751 }
752
753 ZFS_CLOSE(zhp);
754 return (0);
755 }
756
757 /*
758 * Function: be_rollback_callback
759 * Description: Callback function used to iterate through a BE's filesystems
760 * and roll them all back to the specified snapshot name.
761 * Parameters:
762 * zhp - zfs_handle_t pointer to filesystem being processed.
763 * data - name of snapshot to rollback to.
764 * Returns:
765 * 0 - Success
766 * be_errno_t - Failure
767 * Scope:
768 * Private
769 */
770 static int
771 be_rollback_callback(zfs_handle_t *zhp, void *data)
772 {
773 zfs_handle_t *zhp_snap = NULL;
774 char *snap_name = data;
775 char ss[MAXPATHLEN];
776 int ret = 0;
777
778 /* Generate string for this filesystem's snapshot name */
779 (void) snprintf(ss, sizeof (ss), "%s@%s", zfs_get_name(zhp), snap_name);
780
781 /* Get handle to this filesystem's snapshot */
782 if ((zhp_snap = zfs_open(g_zfs, ss, ZFS_TYPE_SNAPSHOT)) == NULL) {
783 be_print_err(gettext("be_rollback_callback: "
784 "failed to open snapshot %s: %s\n"), zfs_get_name(zhp),
785 libzfs_error_description(g_zfs));
786 ret = zfs_err_to_be_err(g_zfs);
787 ZFS_CLOSE(zhp);
788 return (ret);
789 }
790
791 /* Rollback dataset */
792 if (zfs_rollback(zhp, zhp_snap, B_FALSE) != 0) {
793 be_print_err(gettext("be_rollback_callback: "
794 "failed to rollback BE dataset %s to snapshot %s: %s\n"),
795 zfs_get_name(zhp), ss, libzfs_error_description(g_zfs));
796 ret = zfs_err_to_be_err(g_zfs);
797 ZFS_CLOSE(zhp_snap);
798 ZFS_CLOSE(zhp);
799 return (ret);
800 }
801
802 ZFS_CLOSE(zhp_snap);
803 /* Iterate this dataset's children and roll them back */
804 if ((ret = zfs_iter_filesystems(zhp, be_rollback_callback,
805 snap_name)) != 0) {
806 ZFS_CLOSE(zhp);
807 return (ret);
808 }
809
810 ZFS_CLOSE(zhp);
811 return (0);
812 }