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 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
23 * Copyright (c) 2013 by Delphix. All rights reserved.
24 * Copyright (c) 2012, Joyent, Inc. All rights reserved.
25 */
26
27 #include <sys/dmu_objset.h>
28 #include <sys/dsl_dataset.h>
29 #include <sys/dsl_dir.h>
30 #include <sys/dsl_prop.h>
31 #include <sys/dsl_synctask.h>
32 #include <sys/dmu_traverse.h>
33 #include <sys/dmu_impl.h>
34 #include <sys/dmu_tx.h>
35 #include <sys/arc.h>
36 #include <sys/zio.h>
37 #include <sys/zap.h>
38 #include <sys/zfeature.h>
39 #include <sys/unique.h>
40 #include <sys/zfs_context.h>
41 #include <sys/zfs_ioctl.h>
42 #include <sys/spa.h>
43 #include <sys/zfs_znode.h>
44 #include <sys/zfs_onexit.h>
45 #include <sys/zvol.h>
46 #include <sys/dsl_scan.h>
47 #include <sys/dsl_deadlist.h>
48 #include <sys/dsl_destroy.h>
49 #include <sys/dsl_userhold.h>
50 #include <sys/dsl_bookmark.h>
51
52 #define SWITCH64(x, y) \
53 { \
54 uint64_t __tmp = (x); \
55 (x) = (y); \
56 (y) = __tmp; \
57 }
58
59 #define DS_REF_MAX (1ULL << 62)
60
61 #define DSL_DEADLIST_BLOCKSIZE SPA_MAXBLOCKSIZE
62
63 /*
64 * Figure out how much of this delta should be propogated to the dsl_dir
65 * layer. If there's a refreservation, that space has already been
66 * partially accounted for in our ancestors.
67 */
68 static int64_t
69 parent_delta(dsl_dataset_t *ds, int64_t delta)
70 {
71 uint64_t old_bytes, new_bytes;
72
73 if (ds->ds_reserved == 0)
74 return (delta);
75
76 old_bytes = MAX(ds->ds_phys->ds_unique_bytes, ds->ds_reserved);
77 new_bytes = MAX(ds->ds_phys->ds_unique_bytes + delta, ds->ds_reserved);
78
79 ASSERT3U(ABS((int64_t)(new_bytes - old_bytes)), <=, ABS(delta));
80 return (new_bytes - old_bytes);
81 }
82
83 void
84 dsl_dataset_block_born(dsl_dataset_t *ds, const blkptr_t *bp, dmu_tx_t *tx)
85 {
86 int used = bp_get_dsize_sync(tx->tx_pool->dp_spa, bp);
87 int compressed = BP_GET_PSIZE(bp);
88 int uncompressed = BP_GET_UCSIZE(bp);
89 int64_t delta;
90
91 dprintf_bp(bp, "ds=%p", ds);
92
93 ASSERT(dmu_tx_is_syncing(tx));
94 /* It could have been compressed away to nothing */
95 if (BP_IS_HOLE(bp))
96 return;
97 ASSERT(BP_GET_TYPE(bp) != DMU_OT_NONE);
98 ASSERT(DMU_OT_IS_VALID(BP_GET_TYPE(bp)));
99 if (ds == NULL) {
100 dsl_pool_mos_diduse_space(tx->tx_pool,
101 used, compressed, uncompressed);
102 return;
103 }
104
105 dmu_buf_will_dirty(ds->ds_dbuf, tx);
106 mutex_enter(&ds->ds_lock);
107 delta = parent_delta(ds, used);
108 ds->ds_phys->ds_referenced_bytes += used;
109 ds->ds_phys->ds_compressed_bytes += compressed;
110 ds->ds_phys->ds_uncompressed_bytes += uncompressed;
111 ds->ds_phys->ds_unique_bytes += used;
112 mutex_exit(&ds->ds_lock);
113 dsl_dir_diduse_space(ds->ds_dir, DD_USED_HEAD, delta,
114 compressed, uncompressed, tx);
115 dsl_dir_transfer_space(ds->ds_dir, used - delta,
116 DD_USED_REFRSRV, DD_USED_HEAD, tx);
117 }
118
119 int
120 dsl_dataset_block_kill(dsl_dataset_t *ds, const blkptr_t *bp, dmu_tx_t *tx,
121 boolean_t async)
122 {
123 int used = bp_get_dsize_sync(tx->tx_pool->dp_spa, bp);
124 int compressed = BP_GET_PSIZE(bp);
125 int uncompressed = BP_GET_UCSIZE(bp);
126
127 if (BP_IS_HOLE(bp))
128 return (0);
129
130 ASSERT(dmu_tx_is_syncing(tx));
131 ASSERT(bp->blk_birth <= tx->tx_txg);
132
133 if (ds == NULL) {
134 dsl_free(tx->tx_pool, tx->tx_txg, bp);
135 dsl_pool_mos_diduse_space(tx->tx_pool,
136 -used, -compressed, -uncompressed);
137 return (used);
138 }
139 ASSERT3P(tx->tx_pool, ==, ds->ds_dir->dd_pool);
140
141 ASSERT(!dsl_dataset_is_snapshot(ds));
142 dmu_buf_will_dirty(ds->ds_dbuf, tx);
143
144 if (bp->blk_birth > ds->ds_phys->ds_prev_snap_txg) {
145 int64_t delta;
146
147 dprintf_bp(bp, "freeing ds=%llu", ds->ds_object);
148 dsl_free(tx->tx_pool, tx->tx_txg, bp);
149
150 mutex_enter(&ds->ds_lock);
151 ASSERT(ds->ds_phys->ds_unique_bytes >= used ||
152 !DS_UNIQUE_IS_ACCURATE(ds));
153 delta = parent_delta(ds, -used);
154 ds->ds_phys->ds_unique_bytes -= used;
155 mutex_exit(&ds->ds_lock);
156 dsl_dir_diduse_space(ds->ds_dir, DD_USED_HEAD,
157 delta, -compressed, -uncompressed, tx);
158 dsl_dir_transfer_space(ds->ds_dir, -used - delta,
159 DD_USED_REFRSRV, DD_USED_HEAD, tx);
160 } else {
161 dprintf_bp(bp, "putting on dead list: %s", "");
162 if (async) {
163 /*
164 * We are here as part of zio's write done callback,
165 * which means we're a zio interrupt thread. We can't
166 * call dsl_deadlist_insert() now because it may block
167 * waiting for I/O. Instead, put bp on the deferred
168 * queue and let dsl_pool_sync() finish the job.
169 */
170 bplist_append(&ds->ds_pending_deadlist, bp);
171 } else {
172 dsl_deadlist_insert(&ds->ds_deadlist, bp, tx);
173 }
174 ASSERT3U(ds->ds_prev->ds_object, ==,
175 ds->ds_phys->ds_prev_snap_obj);
176 ASSERT(ds->ds_prev->ds_phys->ds_num_children > 0);
177 /* if (bp->blk_birth > prev prev snap txg) prev unique += bs */
178 if (ds->ds_prev->ds_phys->ds_next_snap_obj ==
179 ds->ds_object && bp->blk_birth >
180 ds->ds_prev->ds_phys->ds_prev_snap_txg) {
181 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx);
182 mutex_enter(&ds->ds_prev->ds_lock);
183 ds->ds_prev->ds_phys->ds_unique_bytes += used;
184 mutex_exit(&ds->ds_prev->ds_lock);
185 }
186 if (bp->blk_birth > ds->ds_dir->dd_origin_txg) {
187 dsl_dir_transfer_space(ds->ds_dir, used,
188 DD_USED_HEAD, DD_USED_SNAP, tx);
189 }
190 }
191 mutex_enter(&ds->ds_lock);
192 ASSERT3U(ds->ds_phys->ds_referenced_bytes, >=, used);
193 ds->ds_phys->ds_referenced_bytes -= used;
194 ASSERT3U(ds->ds_phys->ds_compressed_bytes, >=, compressed);
195 ds->ds_phys->ds_compressed_bytes -= compressed;
196 ASSERT3U(ds->ds_phys->ds_uncompressed_bytes, >=, uncompressed);
197 ds->ds_phys->ds_uncompressed_bytes -= uncompressed;
198 mutex_exit(&ds->ds_lock);
199
200 return (used);
201 }
202
203 uint64_t
204 dsl_dataset_prev_snap_txg(dsl_dataset_t *ds)
205 {
206 uint64_t trysnap = 0;
207
208 if (ds == NULL)
209 return (0);
210 /*
211 * The snapshot creation could fail, but that would cause an
212 * incorrect FALSE return, which would only result in an
213 * overestimation of the amount of space that an operation would
214 * consume, which is OK.
215 *
216 * There's also a small window where we could miss a pending
217 * snapshot, because we could set the sync task in the quiescing
218 * phase. So this should only be used as a guess.
219 */
220 if (ds->ds_trysnap_txg >
221 spa_last_synced_txg(ds->ds_dir->dd_pool->dp_spa))
222 trysnap = ds->ds_trysnap_txg;
223 return (MAX(ds->ds_phys->ds_prev_snap_txg, trysnap));
224 }
225
226 boolean_t
227 dsl_dataset_block_freeable(dsl_dataset_t *ds, const blkptr_t *bp,
228 uint64_t blk_birth)
229 {
230 if (blk_birth <= dsl_dataset_prev_snap_txg(ds) ||
231 (bp != NULL && BP_IS_HOLE(bp)))
232 return (B_FALSE);
233
234 ddt_prefetch(dsl_dataset_get_spa(ds), bp);
235
236 return (B_TRUE);
237 }
238
239 /* ARGSUSED */
240 static void
241 dsl_dataset_evict(dmu_buf_t *db, void *dsv)
242 {
243 dsl_dataset_t *ds = dsv;
244
245 ASSERT(ds->ds_owner == NULL);
246
247 unique_remove(ds->ds_fsid_guid);
248
249 if (ds->ds_objset != NULL)
250 dmu_objset_evict(ds->ds_objset);
251
252 if (ds->ds_prev) {
253 dsl_dataset_rele(ds->ds_prev, ds);
254 ds->ds_prev = NULL;
255 }
256
257 bplist_destroy(&ds->ds_pending_deadlist);
258 if (ds->ds_phys->ds_deadlist_obj != 0)
259 dsl_deadlist_close(&ds->ds_deadlist);
260 if (ds->ds_dir)
261 dsl_dir_rele(ds->ds_dir, ds);
262
263 ASSERT(!list_link_active(&ds->ds_synced_link));
264
265 mutex_destroy(&ds->ds_lock);
266 mutex_destroy(&ds->ds_opening_lock);
267 refcount_destroy(&ds->ds_longholds);
268
269 kmem_free(ds, sizeof (dsl_dataset_t));
270 }
271
272 int
273 dsl_dataset_get_snapname(dsl_dataset_t *ds)
274 {
275 dsl_dataset_phys_t *headphys;
276 int err;
277 dmu_buf_t *headdbuf;
278 dsl_pool_t *dp = ds->ds_dir->dd_pool;
279 objset_t *mos = dp->dp_meta_objset;
280
281 if (ds->ds_snapname[0])
282 return (0);
283 if (ds->ds_phys->ds_next_snap_obj == 0)
284 return (0);
285
286 err = dmu_bonus_hold(mos, ds->ds_dir->dd_phys->dd_head_dataset_obj,
287 FTAG, &headdbuf);
288 if (err != 0)
289 return (err);
290 headphys = headdbuf->db_data;
291 err = zap_value_search(dp->dp_meta_objset,
292 headphys->ds_snapnames_zapobj, ds->ds_object, 0, ds->ds_snapname);
293 dmu_buf_rele(headdbuf, FTAG);
294 return (err);
295 }
296
297 int
298 dsl_dataset_snap_lookup(dsl_dataset_t *ds, const char *name, uint64_t *value)
299 {
300 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
301 uint64_t snapobj = ds->ds_phys->ds_snapnames_zapobj;
302 matchtype_t mt;
303 int err;
304
305 if (ds->ds_phys->ds_flags & DS_FLAG_CI_DATASET)
306 mt = MT_FIRST;
307 else
308 mt = MT_EXACT;
309
310 err = zap_lookup_norm(mos, snapobj, name, 8, 1,
311 value, mt, NULL, 0, NULL);
312 if (err == ENOTSUP && mt == MT_FIRST)
313 err = zap_lookup(mos, snapobj, name, 8, 1, value);
314 return (err);
315 }
316
317 int
318 dsl_dataset_snap_remove(dsl_dataset_t *ds, const char *name, dmu_tx_t *tx)
319 {
320 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
321 uint64_t snapobj = ds->ds_phys->ds_snapnames_zapobj;
322 matchtype_t mt;
323 int err;
324
325 dsl_dir_snap_cmtime_update(ds->ds_dir);
326
327 if (ds->ds_phys->ds_flags & DS_FLAG_CI_DATASET)
328 mt = MT_FIRST;
329 else
330 mt = MT_EXACT;
331
332 err = zap_remove_norm(mos, snapobj, name, mt, tx);
333 if (err == ENOTSUP && mt == MT_FIRST)
334 err = zap_remove(mos, snapobj, name, tx);
335 return (err);
336 }
337
338 int
339 dsl_dataset_hold_obj(dsl_pool_t *dp, uint64_t dsobj, void *tag,
340 dsl_dataset_t **dsp)
341 {
342 objset_t *mos = dp->dp_meta_objset;
343 dmu_buf_t *dbuf;
344 dsl_dataset_t *ds;
345 int err;
346 dmu_object_info_t doi;
347
348 ASSERT(dsl_pool_config_held(dp));
349
350 err = dmu_bonus_hold(mos, dsobj, tag, &dbuf);
351 if (err != 0)
352 return (err);
353
354 /* Make sure dsobj has the correct object type. */
355 dmu_object_info_from_db(dbuf, &doi);
356 if (doi.doi_bonus_type != DMU_OT_DSL_DATASET) {
357 dmu_buf_rele(dbuf, tag);
358 return (SET_ERROR(EINVAL));
359 }
360
361 ds = dmu_buf_get_user(dbuf);
362 if (ds == NULL) {
363 dsl_dataset_t *winner = NULL;
364
365 ds = kmem_zalloc(sizeof (dsl_dataset_t), KM_SLEEP);
366 ds->ds_dbuf = dbuf;
367 ds->ds_object = dsobj;
368 ds->ds_phys = dbuf->db_data;
369
370 mutex_init(&ds->ds_lock, NULL, MUTEX_DEFAULT, NULL);
371 mutex_init(&ds->ds_opening_lock, NULL, MUTEX_DEFAULT, NULL);
372 mutex_init(&ds->ds_sendstream_lock, NULL, MUTEX_DEFAULT, NULL);
373 refcount_create(&ds->ds_longholds);
374
375 bplist_create(&ds->ds_pending_deadlist);
376 dsl_deadlist_open(&ds->ds_deadlist,
377 mos, ds->ds_phys->ds_deadlist_obj);
378
379 list_create(&ds->ds_sendstreams, sizeof (dmu_sendarg_t),
380 offsetof(dmu_sendarg_t, dsa_link));
381
382 if (err == 0) {
383 err = dsl_dir_hold_obj(dp,
384 ds->ds_phys->ds_dir_obj, NULL, ds, &ds->ds_dir);
385 }
386 if (err != 0) {
387 mutex_destroy(&ds->ds_lock);
388 mutex_destroy(&ds->ds_opening_lock);
389 refcount_destroy(&ds->ds_longholds);
390 bplist_destroy(&ds->ds_pending_deadlist);
391 dsl_deadlist_close(&ds->ds_deadlist);
392 kmem_free(ds, sizeof (dsl_dataset_t));
393 dmu_buf_rele(dbuf, tag);
394 return (err);
395 }
396
397 if (!dsl_dataset_is_snapshot(ds)) {
398 ds->ds_snapname[0] = '\0';
399 if (ds->ds_phys->ds_prev_snap_obj != 0) {
400 err = dsl_dataset_hold_obj(dp,
401 ds->ds_phys->ds_prev_snap_obj,
402 ds, &ds->ds_prev);
403 }
404 if (doi.doi_type == DMU_OTN_ZAP_METADATA) {
405 int zaperr = zap_lookup(mos, ds->ds_object,
406 DS_FIELD_BOOKMARK_NAMES,
407 sizeof (ds->ds_bookmarks), 1,
408 &ds->ds_bookmarks);
409 if (zaperr != ENOENT)
410 VERIFY0(zaperr);
411 }
412 } else {
413 if (zfs_flags & ZFS_DEBUG_SNAPNAMES)
414 err = dsl_dataset_get_snapname(ds);
415 if (err == 0 && ds->ds_phys->ds_userrefs_obj != 0) {
416 err = zap_count(
417 ds->ds_dir->dd_pool->dp_meta_objset,
418 ds->ds_phys->ds_userrefs_obj,
419 &ds->ds_userrefs);
420 }
421 }
422
423 if (err == 0 && !dsl_dataset_is_snapshot(ds)) {
424 err = dsl_prop_get_int_ds(ds,
425 zfs_prop_to_name(ZFS_PROP_REFRESERVATION),
426 &ds->ds_reserved);
427 if (err == 0) {
428 err = dsl_prop_get_int_ds(ds,
429 zfs_prop_to_name(ZFS_PROP_REFQUOTA),
430 &ds->ds_quota);
431 }
432 } else {
433 ds->ds_reserved = ds->ds_quota = 0;
434 }
435
436 if (err != 0 || (winner = dmu_buf_set_user_ie(dbuf, ds,
437 &ds->ds_phys, dsl_dataset_evict)) != NULL) {
438 bplist_destroy(&ds->ds_pending_deadlist);
439 dsl_deadlist_close(&ds->ds_deadlist);
440 if (ds->ds_prev)
441 dsl_dataset_rele(ds->ds_prev, ds);
442 dsl_dir_rele(ds->ds_dir, ds);
443 mutex_destroy(&ds->ds_lock);
444 mutex_destroy(&ds->ds_opening_lock);
445 refcount_destroy(&ds->ds_longholds);
446 kmem_free(ds, sizeof (dsl_dataset_t));
447 if (err != 0) {
448 dmu_buf_rele(dbuf, tag);
449 return (err);
450 }
451 ds = winner;
452 } else {
453 ds->ds_fsid_guid =
454 unique_insert(ds->ds_phys->ds_fsid_guid);
455 }
456 }
457 ASSERT3P(ds->ds_dbuf, ==, dbuf);
458 ASSERT3P(ds->ds_phys, ==, dbuf->db_data);
459 ASSERT(ds->ds_phys->ds_prev_snap_obj != 0 ||
460 spa_version(dp->dp_spa) < SPA_VERSION_ORIGIN ||
461 dp->dp_origin_snap == NULL || ds == dp->dp_origin_snap);
462 *dsp = ds;
463 return (0);
464 }
465
466 int
467 dsl_dataset_hold(dsl_pool_t *dp, const char *name,
468 void *tag, dsl_dataset_t **dsp)
469 {
470 dsl_dir_t *dd;
471 const char *snapname;
472 uint64_t obj;
473 int err = 0;
474
475 err = dsl_dir_hold(dp, name, FTAG, &dd, &snapname);
476 if (err != 0)
477 return (err);
478
479 ASSERT(dsl_pool_config_held(dp));
480 obj = dd->dd_phys->dd_head_dataset_obj;
481 if (obj != 0)
482 err = dsl_dataset_hold_obj(dp, obj, tag, dsp);
483 else
484 err = SET_ERROR(ENOENT);
485
486 /* we may be looking for a snapshot */
487 if (err == 0 && snapname != NULL) {
488 dsl_dataset_t *ds;
489
490 if (*snapname++ != '@') {
491 dsl_dataset_rele(*dsp, tag);
492 dsl_dir_rele(dd, FTAG);
493 return (SET_ERROR(ENOENT));
494 }
495
496 dprintf("looking for snapshot '%s'\n", snapname);
497 err = dsl_dataset_snap_lookup(*dsp, snapname, &obj);
498 if (err == 0)
499 err = dsl_dataset_hold_obj(dp, obj, tag, &ds);
500 dsl_dataset_rele(*dsp, tag);
501
502 if (err == 0) {
503 mutex_enter(&ds->ds_lock);
504 if (ds->ds_snapname[0] == 0)
505 (void) strlcpy(ds->ds_snapname, snapname,
506 sizeof (ds->ds_snapname));
507 mutex_exit(&ds->ds_lock);
508 *dsp = ds;
509 }
510 }
511
512 dsl_dir_rele(dd, FTAG);
513 return (err);
514 }
515
516 int
517 dsl_dataset_own_obj(dsl_pool_t *dp, uint64_t dsobj,
518 void *tag, dsl_dataset_t **dsp)
519 {
520 int err = dsl_dataset_hold_obj(dp, dsobj, tag, dsp);
521 if (err != 0)
522 return (err);
523 if (!dsl_dataset_tryown(*dsp, tag)) {
524 dsl_dataset_rele(*dsp, tag);
525 *dsp = NULL;
526 return (SET_ERROR(EBUSY));
527 }
528 return (0);
529 }
530
531 int
532 dsl_dataset_own(dsl_pool_t *dp, const char *name,
533 void *tag, dsl_dataset_t **dsp)
534 {
535 int err = dsl_dataset_hold(dp, name, tag, dsp);
536 if (err != 0)
537 return (err);
538 if (!dsl_dataset_tryown(*dsp, tag)) {
539 dsl_dataset_rele(*dsp, tag);
540 return (SET_ERROR(EBUSY));
541 }
542 return (0);
543 }
544
545 /*
546 * See the comment above dsl_pool_hold() for details. In summary, a long
547 * hold is used to prevent destruction of a dataset while the pool hold
548 * is dropped, allowing other concurrent operations (e.g. spa_sync()).
549 *
550 * The dataset and pool must be held when this function is called. After it
551 * is called, the pool hold may be released while the dataset is still held
552 * and accessed.
553 */
554 void
555 dsl_dataset_long_hold(dsl_dataset_t *ds, void *tag)
556 {
557 ASSERT(dsl_pool_config_held(ds->ds_dir->dd_pool));
558 (void) refcount_add(&ds->ds_longholds, tag);
559 }
560
561 void
562 dsl_dataset_long_rele(dsl_dataset_t *ds, void *tag)
563 {
564 (void) refcount_remove(&ds->ds_longholds, tag);
565 }
566
567 /* Return B_TRUE if there are any long holds on this dataset. */
568 boolean_t
569 dsl_dataset_long_held(dsl_dataset_t *ds)
570 {
571 return (!refcount_is_zero(&ds->ds_longholds));
572 }
573
574 void
575 dsl_dataset_name(dsl_dataset_t *ds, char *name)
576 {
577 if (ds == NULL) {
578 (void) strcpy(name, "mos");
579 } else {
580 dsl_dir_name(ds->ds_dir, name);
581 VERIFY0(dsl_dataset_get_snapname(ds));
582 if (ds->ds_snapname[0]) {
583 (void) strcat(name, "@");
584 /*
585 * We use a "recursive" mutex so that we
586 * can call dprintf_ds() with ds_lock held.
587 */
588 if (!MUTEX_HELD(&ds->ds_lock)) {
589 mutex_enter(&ds->ds_lock);
590 (void) strcat(name, ds->ds_snapname);
591 mutex_exit(&ds->ds_lock);
592 } else {
593 (void) strcat(name, ds->ds_snapname);
594 }
595 }
596 }
597 }
598
599 void
600 dsl_dataset_rele(dsl_dataset_t *ds, void *tag)
601 {
602 dmu_buf_rele(ds->ds_dbuf, tag);
603 }
604
605 void
606 dsl_dataset_disown(dsl_dataset_t *ds, void *tag)
607 {
608 ASSERT(ds->ds_owner == tag && ds->ds_dbuf != NULL);
609
610 mutex_enter(&ds->ds_lock);
611 ds->ds_owner = NULL;
612 mutex_exit(&ds->ds_lock);
613 dsl_dataset_long_rele(ds, tag);
614 if (ds->ds_dbuf != NULL)
615 dsl_dataset_rele(ds, tag);
616 else
617 dsl_dataset_evict(NULL, ds);
618 }
619
620 boolean_t
621 dsl_dataset_tryown(dsl_dataset_t *ds, void *tag)
622 {
623 boolean_t gotit = FALSE;
624
625 mutex_enter(&ds->ds_lock);
626 if (ds->ds_owner == NULL && !DS_IS_INCONSISTENT(ds)) {
627 ds->ds_owner = tag;
628 dsl_dataset_long_hold(ds, tag);
629 gotit = TRUE;
630 }
631 mutex_exit(&ds->ds_lock);
632 return (gotit);
633 }
634
635 uint64_t
636 dsl_dataset_create_sync_dd(dsl_dir_t *dd, dsl_dataset_t *origin,
637 uint64_t flags, dmu_tx_t *tx)
638 {
639 dsl_pool_t *dp = dd->dd_pool;
640 dmu_buf_t *dbuf;
641 dsl_dataset_phys_t *dsphys;
642 uint64_t dsobj;
643 objset_t *mos = dp->dp_meta_objset;
644
645 if (origin == NULL)
646 origin = dp->dp_origin_snap;
647
648 ASSERT(origin == NULL || origin->ds_dir->dd_pool == dp);
649 ASSERT(origin == NULL || origin->ds_phys->ds_num_children > 0);
650 ASSERT(dmu_tx_is_syncing(tx));
651 ASSERT(dd->dd_phys->dd_head_dataset_obj == 0);
652
653 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0,
654 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx);
655 VERIFY0(dmu_bonus_hold(mos, dsobj, FTAG, &dbuf));
656 dmu_buf_will_dirty(dbuf, tx);
657 dsphys = dbuf->db_data;
658 bzero(dsphys, sizeof (dsl_dataset_phys_t));
659 dsphys->ds_dir_obj = dd->dd_object;
660 dsphys->ds_flags = flags;
661 dsphys->ds_fsid_guid = unique_create();
662 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid,
663 sizeof (dsphys->ds_guid));
664 dsphys->ds_snapnames_zapobj =
665 zap_create_norm(mos, U8_TEXTPREP_TOUPPER, DMU_OT_DSL_DS_SNAP_MAP,
666 DMU_OT_NONE, 0, tx);
667 dsphys->ds_creation_time = gethrestime_sec();
668 dsphys->ds_creation_txg = tx->tx_txg == TXG_INITIAL ? 1 : tx->tx_txg;
669
670 if (origin == NULL) {
671 dsphys->ds_deadlist_obj = dsl_deadlist_alloc(mos, tx);
672 } else {
673 dsl_dataset_t *ohds; /* head of the origin snapshot */
674
675 dsphys->ds_prev_snap_obj = origin->ds_object;
676 dsphys->ds_prev_snap_txg =
677 origin->ds_phys->ds_creation_txg;
678 dsphys->ds_referenced_bytes =
679 origin->ds_phys->ds_referenced_bytes;
680 dsphys->ds_compressed_bytes =
681 origin->ds_phys->ds_compressed_bytes;
682 dsphys->ds_uncompressed_bytes =
683 origin->ds_phys->ds_uncompressed_bytes;
684 dsphys->ds_bp = origin->ds_phys->ds_bp;
685 dsphys->ds_flags |= origin->ds_phys->ds_flags;
686
687 dmu_buf_will_dirty(origin->ds_dbuf, tx);
688 origin->ds_phys->ds_num_children++;
689
690 VERIFY0(dsl_dataset_hold_obj(dp,
691 origin->ds_dir->dd_phys->dd_head_dataset_obj, FTAG, &ohds));
692 dsphys->ds_deadlist_obj = dsl_deadlist_clone(&ohds->ds_deadlist,
693 dsphys->ds_prev_snap_txg, dsphys->ds_prev_snap_obj, tx);
694 dsl_dataset_rele(ohds, FTAG);
695
696 if (spa_version(dp->dp_spa) >= SPA_VERSION_NEXT_CLONES) {
697 if (origin->ds_phys->ds_next_clones_obj == 0) {
698 origin->ds_phys->ds_next_clones_obj =
699 zap_create(mos,
700 DMU_OT_NEXT_CLONES, DMU_OT_NONE, 0, tx);
701 }
702 VERIFY0(zap_add_int(mos,
703 origin->ds_phys->ds_next_clones_obj, dsobj, tx));
704 }
705
706 dmu_buf_will_dirty(dd->dd_dbuf, tx);
707 dd->dd_phys->dd_origin_obj = origin->ds_object;
708 if (spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) {
709 if (origin->ds_dir->dd_phys->dd_clones == 0) {
710 dmu_buf_will_dirty(origin->ds_dir->dd_dbuf, tx);
711 origin->ds_dir->dd_phys->dd_clones =
712 zap_create(mos,
713 DMU_OT_DSL_CLONES, DMU_OT_NONE, 0, tx);
714 }
715 VERIFY0(zap_add_int(mos,
716 origin->ds_dir->dd_phys->dd_clones, dsobj, tx));
717 }
718 }
719
720 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE)
721 dsphys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE;
722
723 dmu_buf_rele(dbuf, FTAG);
724
725 dmu_buf_will_dirty(dd->dd_dbuf, tx);
726 dd->dd_phys->dd_head_dataset_obj = dsobj;
727
728 return (dsobj);
729 }
730
731 static void
732 dsl_dataset_zero_zil(dsl_dataset_t *ds, dmu_tx_t *tx)
733 {
734 objset_t *os;
735
736 VERIFY0(dmu_objset_from_ds(ds, &os));
737 bzero(&os->os_zil_header, sizeof (os->os_zil_header));
738 dsl_dataset_dirty(ds, tx);
739 }
740
741 uint64_t
742 dsl_dataset_create_sync(dsl_dir_t *pdd, const char *lastname,
743 dsl_dataset_t *origin, uint64_t flags, cred_t *cr, dmu_tx_t *tx)
744 {
745 dsl_pool_t *dp = pdd->dd_pool;
746 uint64_t dsobj, ddobj;
747 dsl_dir_t *dd;
748
749 ASSERT(dmu_tx_is_syncing(tx));
750 ASSERT(lastname[0] != '@');
751
752 ddobj = dsl_dir_create_sync(dp, pdd, lastname, tx);
753 VERIFY0(dsl_dir_hold_obj(dp, ddobj, lastname, FTAG, &dd));
754
755 dsobj = dsl_dataset_create_sync_dd(dd, origin,
756 flags & ~DS_CREATE_FLAG_NODIRTY, tx);
757
758 dsl_deleg_set_create_perms(dd, tx, cr);
759
760 dsl_dir_rele(dd, FTAG);
761
762 /*
763 * If we are creating a clone, make sure we zero out any stale
764 * data from the origin snapshots zil header.
765 */
766 if (origin != NULL && !(flags & DS_CREATE_FLAG_NODIRTY)) {
767 dsl_dataset_t *ds;
768
769 VERIFY0(dsl_dataset_hold_obj(dp, dsobj, FTAG, &ds));
770 dsl_dataset_zero_zil(ds, tx);
771 dsl_dataset_rele(ds, FTAG);
772 }
773
774 return (dsobj);
775 }
776
777 /*
778 * The unique space in the head dataset can be calculated by subtracting
779 * the space used in the most recent snapshot, that is still being used
780 * in this file system, from the space currently in use. To figure out
781 * the space in the most recent snapshot still in use, we need to take
782 * the total space used in the snapshot and subtract out the space that
783 * has been freed up since the snapshot was taken.
784 */
785 void
786 dsl_dataset_recalc_head_uniq(dsl_dataset_t *ds)
787 {
788 uint64_t mrs_used;
789 uint64_t dlused, dlcomp, dluncomp;
790
791 ASSERT(!dsl_dataset_is_snapshot(ds));
792
793 if (ds->ds_phys->ds_prev_snap_obj != 0)
794 mrs_used = ds->ds_prev->ds_phys->ds_referenced_bytes;
795 else
796 mrs_used = 0;
797
798 dsl_deadlist_space(&ds->ds_deadlist, &dlused, &dlcomp, &dluncomp);
799
800 ASSERT3U(dlused, <=, mrs_used);
801 ds->ds_phys->ds_unique_bytes =
802 ds->ds_phys->ds_referenced_bytes - (mrs_used - dlused);
803
804 if (spa_version(ds->ds_dir->dd_pool->dp_spa) >=
805 SPA_VERSION_UNIQUE_ACCURATE)
806 ds->ds_phys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE;
807 }
808
809 void
810 dsl_dataset_remove_from_next_clones(dsl_dataset_t *ds, uint64_t obj,
811 dmu_tx_t *tx)
812 {
813 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
814 uint64_t count;
815 int err;
816
817 ASSERT(ds->ds_phys->ds_num_children >= 2);
818 err = zap_remove_int(mos, ds->ds_phys->ds_next_clones_obj, obj, tx);
819 /*
820 * The err should not be ENOENT, but a bug in a previous version
821 * of the code could cause upgrade_clones_cb() to not set
822 * ds_next_snap_obj when it should, leading to a missing entry.
823 * If we knew that the pool was created after
824 * SPA_VERSION_NEXT_CLONES, we could assert that it isn't
825 * ENOENT. However, at least we can check that we don't have
826 * too many entries in the next_clones_obj even after failing to
827 * remove this one.
828 */
829 if (err != ENOENT)
830 VERIFY0(err);
831 ASSERT0(zap_count(mos, ds->ds_phys->ds_next_clones_obj,
832 &count));
833 ASSERT3U(count, <=, ds->ds_phys->ds_num_children - 2);
834 }
835
836
837 blkptr_t *
838 dsl_dataset_get_blkptr(dsl_dataset_t *ds)
839 {
840 return (&ds->ds_phys->ds_bp);
841 }
842
843 void
844 dsl_dataset_set_blkptr(dsl_dataset_t *ds, blkptr_t *bp, dmu_tx_t *tx)
845 {
846 ASSERT(dmu_tx_is_syncing(tx));
847 /* If it's the meta-objset, set dp_meta_rootbp */
848 if (ds == NULL) {
849 tx->tx_pool->dp_meta_rootbp = *bp;
850 } else {
851 dmu_buf_will_dirty(ds->ds_dbuf, tx);
852 ds->ds_phys->ds_bp = *bp;
853 }
854 }
855
856 spa_t *
857 dsl_dataset_get_spa(dsl_dataset_t *ds)
858 {
859 return (ds->ds_dir->dd_pool->dp_spa);
860 }
861
862 void
863 dsl_dataset_dirty(dsl_dataset_t *ds, dmu_tx_t *tx)
864 {
865 dsl_pool_t *dp;
866
867 if (ds == NULL) /* this is the meta-objset */
868 return;
869
870 ASSERT(ds->ds_objset != NULL);
871
872 if (ds->ds_phys->ds_next_snap_obj != 0)
873 panic("dirtying snapshot!");
874
875 dp = ds->ds_dir->dd_pool;
876
877 if (txg_list_add(&dp->dp_dirty_datasets, ds, tx->tx_txg)) {
878 /* up the hold count until we can be written out */
879 dmu_buf_add_ref(ds->ds_dbuf, ds);
880 }
881 }
882
883 boolean_t
884 dsl_dataset_is_dirty(dsl_dataset_t *ds)
885 {
886 for (int t = 0; t < TXG_SIZE; t++) {
887 if (txg_list_member(&ds->ds_dir->dd_pool->dp_dirty_datasets,
888 ds, t))
889 return (B_TRUE);
890 }
891 return (B_FALSE);
892 }
893
894 static int
895 dsl_dataset_snapshot_reserve_space(dsl_dataset_t *ds, dmu_tx_t *tx)
896 {
897 uint64_t asize;
898
899 if (!dmu_tx_is_syncing(tx))
900 return (0);
901
902 /*
903 * If there's an fs-only reservation, any blocks that might become
904 * owned by the snapshot dataset must be accommodated by space
905 * outside of the reservation.
906 */
907 ASSERT(ds->ds_reserved == 0 || DS_UNIQUE_IS_ACCURATE(ds));
908 asize = MIN(ds->ds_phys->ds_unique_bytes, ds->ds_reserved);
909 if (asize > dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE))
910 return (SET_ERROR(ENOSPC));
911
912 /*
913 * Propagate any reserved space for this snapshot to other
914 * snapshot checks in this sync group.
915 */
916 if (asize > 0)
917 dsl_dir_willuse_space(ds->ds_dir, asize, tx);
918
919 return (0);
920 }
921
922 typedef struct dsl_dataset_snapshot_arg {
923 nvlist_t *ddsa_snaps;
924 nvlist_t *ddsa_props;
925 nvlist_t *ddsa_errors;
926 } dsl_dataset_snapshot_arg_t;
927
928 int
929 dsl_dataset_snapshot_check_impl(dsl_dataset_t *ds, const char *snapname,
930 dmu_tx_t *tx, boolean_t recv)
931 {
932 int error;
933 uint64_t value;
934
935 ds->ds_trysnap_txg = tx->tx_txg;
936
937 if (!dmu_tx_is_syncing(tx))
938 return (0);
939
940 /*
941 * We don't allow multiple snapshots of the same txg. If there
942 * is already one, try again.
943 */
944 if (ds->ds_phys->ds_prev_snap_txg >= tx->tx_txg)
945 return (SET_ERROR(EAGAIN));
946
947 /*
948 * Check for conflicting snapshot name.
949 */
950 error = dsl_dataset_snap_lookup(ds, snapname, &value);
951 if (error == 0)
952 return (SET_ERROR(EEXIST));
953 if (error != ENOENT)
954 return (error);
955
956 /*
957 * We don't allow taking snapshots of inconsistent datasets, such as
958 * those into which we are currently receiving. However, if we are
959 * creating this snapshot as part of a receive, this check will be
960 * executed atomically with respect to the completion of the receive
961 * itself but prior to the clearing of DS_FLAG_INCONSISTENT; in this
962 * case we ignore this, knowing it will be fixed up for us shortly in
963 * dmu_recv_end_sync().
964 */
965 if (!recv && DS_IS_INCONSISTENT(ds))
966 return (SET_ERROR(EBUSY));
967
968 error = dsl_dataset_snapshot_reserve_space(ds, tx);
969 if (error != 0)
970 return (error);
971
972 return (0);
973 }
974
975 static int
976 dsl_dataset_snapshot_check(void *arg, dmu_tx_t *tx)
977 {
978 dsl_dataset_snapshot_arg_t *ddsa = arg;
979 dsl_pool_t *dp = dmu_tx_pool(tx);
980 nvpair_t *pair;
981 int rv = 0;
982
983 for (pair = nvlist_next_nvpair(ddsa->ddsa_snaps, NULL);
984 pair != NULL; pair = nvlist_next_nvpair(ddsa->ddsa_snaps, pair)) {
985 int error = 0;
986 dsl_dataset_t *ds;
987 char *name, *atp;
988 char dsname[MAXNAMELEN];
989
990 name = nvpair_name(pair);
991 if (strlen(name) >= MAXNAMELEN)
992 error = SET_ERROR(ENAMETOOLONG);
993 if (error == 0) {
994 atp = strchr(name, '@');
995 if (atp == NULL)
996 error = SET_ERROR(EINVAL);
997 if (error == 0)
998 (void) strlcpy(dsname, name, atp - name + 1);
999 }
1000 if (error == 0)
1001 error = dsl_dataset_hold(dp, dsname, FTAG, &ds);
1002 if (error == 0) {
1003 error = dsl_dataset_snapshot_check_impl(ds,
1004 atp + 1, tx, B_FALSE);
1005 dsl_dataset_rele(ds, FTAG);
1006 }
1007
1008 if (error != 0) {
1009 if (ddsa->ddsa_errors != NULL) {
1010 fnvlist_add_int32(ddsa->ddsa_errors,
1011 name, error);
1012 }
1013 rv = error;
1014 }
1015 }
1016 return (rv);
1017 }
1018
1019 void
1020 dsl_dataset_snapshot_sync_impl(dsl_dataset_t *ds, const char *snapname,
1021 dmu_tx_t *tx)
1022 {
1023 static zil_header_t zero_zil;
1024
1025 dsl_pool_t *dp = ds->ds_dir->dd_pool;
1026 dmu_buf_t *dbuf;
1027 dsl_dataset_phys_t *dsphys;
1028 uint64_t dsobj, crtxg;
1029 objset_t *mos = dp->dp_meta_objset;
1030 objset_t *os;
1031
1032 ASSERT(RRW_WRITE_HELD(&dp->dp_config_rwlock));
1033
1034 /*
1035 * If we are on an old pool, the zil must not be active, in which
1036 * case it will be zeroed. Usually zil_suspend() accomplishes this.
1037 */
1038 ASSERT(spa_version(dmu_tx_pool(tx)->dp_spa) >= SPA_VERSION_FAST_SNAP ||
1039 dmu_objset_from_ds(ds, &os) != 0 ||
1040 bcmp(&os->os_phys->os_zil_header, &zero_zil,
1041 sizeof (zero_zil)) == 0);
1042
1043
1044 /*
1045 * The origin's ds_creation_txg has to be < TXG_INITIAL
1046 */
1047 if (strcmp(snapname, ORIGIN_DIR_NAME) == 0)
1048 crtxg = 1;
1049 else
1050 crtxg = tx->tx_txg;
1051
1052 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0,
1053 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx);
1054 VERIFY0(dmu_bonus_hold(mos, dsobj, FTAG, &dbuf));
1055 dmu_buf_will_dirty(dbuf, tx);
1056 dsphys = dbuf->db_data;
1057 bzero(dsphys, sizeof (dsl_dataset_phys_t));
1058 dsphys->ds_dir_obj = ds->ds_dir->dd_object;
1059 dsphys->ds_fsid_guid = unique_create();
1060 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid,
1061 sizeof (dsphys->ds_guid));
1062 dsphys->ds_prev_snap_obj = ds->ds_phys->ds_prev_snap_obj;
1063 dsphys->ds_prev_snap_txg = ds->ds_phys->ds_prev_snap_txg;
1064 dsphys->ds_next_snap_obj = ds->ds_object;
1065 dsphys->ds_num_children = 1;
1066 dsphys->ds_creation_time = gethrestime_sec();
1067 dsphys->ds_creation_txg = crtxg;
1068 dsphys->ds_deadlist_obj = ds->ds_phys->ds_deadlist_obj;
1069 dsphys->ds_referenced_bytes = ds->ds_phys->ds_referenced_bytes;
1070 dsphys->ds_compressed_bytes = ds->ds_phys->ds_compressed_bytes;
1071 dsphys->ds_uncompressed_bytes = ds->ds_phys->ds_uncompressed_bytes;
1072 dsphys->ds_flags = ds->ds_phys->ds_flags;
1073 dsphys->ds_bp = ds->ds_phys->ds_bp;
1074 dmu_buf_rele(dbuf, FTAG);
1075
1076 ASSERT3U(ds->ds_prev != 0, ==, ds->ds_phys->ds_prev_snap_obj != 0);
1077 if (ds->ds_prev) {
1078 uint64_t next_clones_obj =
1079 ds->ds_prev->ds_phys->ds_next_clones_obj;
1080 ASSERT(ds->ds_prev->ds_phys->ds_next_snap_obj ==
1081 ds->ds_object ||
1082 ds->ds_prev->ds_phys->ds_num_children > 1);
1083 if (ds->ds_prev->ds_phys->ds_next_snap_obj == ds->ds_object) {
1084 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx);
1085 ASSERT3U(ds->ds_phys->ds_prev_snap_txg, ==,
1086 ds->ds_prev->ds_phys->ds_creation_txg);
1087 ds->ds_prev->ds_phys->ds_next_snap_obj = dsobj;
1088 } else if (next_clones_obj != 0) {
1089 dsl_dataset_remove_from_next_clones(ds->ds_prev,
1090 dsphys->ds_next_snap_obj, tx);
1091 VERIFY0(zap_add_int(mos,
1092 next_clones_obj, dsobj, tx));
1093 }
1094 }
1095
1096 /*
1097 * If we have a reference-reservation on this dataset, we will
1098 * need to increase the amount of refreservation being charged
1099 * since our unique space is going to zero.
1100 */
1101 if (ds->ds_reserved) {
1102 int64_t delta;
1103 ASSERT(DS_UNIQUE_IS_ACCURATE(ds));
1104 delta = MIN(ds->ds_phys->ds_unique_bytes, ds->ds_reserved);
1105 dsl_dir_diduse_space(ds->ds_dir, DD_USED_REFRSRV,
1106 delta, 0, 0, tx);
1107 }
1108
1109 dmu_buf_will_dirty(ds->ds_dbuf, tx);
1110 ds->ds_phys->ds_deadlist_obj = dsl_deadlist_clone(&ds->ds_deadlist,
1111 UINT64_MAX, ds->ds_phys->ds_prev_snap_obj, tx);
1112 dsl_deadlist_close(&ds->ds_deadlist);
1113 dsl_deadlist_open(&ds->ds_deadlist, mos, ds->ds_phys->ds_deadlist_obj);
1114 dsl_deadlist_add_key(&ds->ds_deadlist,
1115 ds->ds_phys->ds_prev_snap_txg, tx);
1116
1117 ASSERT3U(ds->ds_phys->ds_prev_snap_txg, <, tx->tx_txg);
1118 ds->ds_phys->ds_prev_snap_obj = dsobj;
1119 ds->ds_phys->ds_prev_snap_txg = crtxg;
1120 ds->ds_phys->ds_unique_bytes = 0;
1121 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE)
1122 ds->ds_phys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE;
1123
1124 VERIFY0(zap_add(mos, ds->ds_phys->ds_snapnames_zapobj,
1125 snapname, 8, 1, &dsobj, tx));
1126
1127 if (ds->ds_prev)
1128 dsl_dataset_rele(ds->ds_prev, ds);
1129 VERIFY0(dsl_dataset_hold_obj(dp,
1130 ds->ds_phys->ds_prev_snap_obj, ds, &ds->ds_prev));
1131
1132 dsl_scan_ds_snapshotted(ds, tx);
1133
1134 dsl_dir_snap_cmtime_update(ds->ds_dir);
1135
1136 spa_history_log_internal_ds(ds->ds_prev, "snapshot", tx, "");
1137 }
1138
1139 static void
1140 dsl_dataset_snapshot_sync(void *arg, dmu_tx_t *tx)
1141 {
1142 dsl_dataset_snapshot_arg_t *ddsa = arg;
1143 dsl_pool_t *dp = dmu_tx_pool(tx);
1144 nvpair_t *pair;
1145
1146 for (pair = nvlist_next_nvpair(ddsa->ddsa_snaps, NULL);
1147 pair != NULL; pair = nvlist_next_nvpair(ddsa->ddsa_snaps, pair)) {
1148 dsl_dataset_t *ds;
1149 char *name, *atp;
1150 char dsname[MAXNAMELEN];
1151
1152 name = nvpair_name(pair);
1153 atp = strchr(name, '@');
1154 (void) strlcpy(dsname, name, atp - name + 1);
1155 VERIFY0(dsl_dataset_hold(dp, dsname, FTAG, &ds));
1156
1157 dsl_dataset_snapshot_sync_impl(ds, atp + 1, tx);
1158 if (ddsa->ddsa_props != NULL) {
1159 dsl_props_set_sync_impl(ds->ds_prev,
1160 ZPROP_SRC_LOCAL, ddsa->ddsa_props, tx);
1161 }
1162 dsl_dataset_rele(ds, FTAG);
1163 }
1164 }
1165
1166 /*
1167 * The snapshots must all be in the same pool.
1168 * All-or-nothing: if there are any failures, nothing will be modified.
1169 */
1170 int
1171 dsl_dataset_snapshot(nvlist_t *snaps, nvlist_t *props, nvlist_t *errors)
1172 {
1173 dsl_dataset_snapshot_arg_t ddsa;
1174 nvpair_t *pair;
1175 boolean_t needsuspend;
1176 int error;
1177 spa_t *spa;
1178 char *firstname;
1179 nvlist_t *suspended = NULL;
1180
1181 pair = nvlist_next_nvpair(snaps, NULL);
1182 if (pair == NULL)
1183 return (0);
1184 firstname = nvpair_name(pair);
1185
1186 error = spa_open(firstname, &spa, FTAG);
1187 if (error != 0)
1188 return (error);
1189 needsuspend = (spa_version(spa) < SPA_VERSION_FAST_SNAP);
1190 spa_close(spa, FTAG);
1191
1192 if (needsuspend) {
1193 suspended = fnvlist_alloc();
1194 for (pair = nvlist_next_nvpair(snaps, NULL); pair != NULL;
1195 pair = nvlist_next_nvpair(snaps, pair)) {
1196 char fsname[MAXNAMELEN];
1197 char *snapname = nvpair_name(pair);
1198 char *atp;
1199 void *cookie;
1200
1201 atp = strchr(snapname, '@');
1202 if (atp == NULL) {
1203 error = SET_ERROR(EINVAL);
1204 break;
1205 }
1206 (void) strlcpy(fsname, snapname, atp - snapname + 1);
1207
1208 error = zil_suspend(fsname, &cookie);
1209 if (error != 0)
1210 break;
1211 fnvlist_add_uint64(suspended, fsname,
1212 (uintptr_t)cookie);
1213 }
1214 }
1215
1216 ddsa.ddsa_snaps = snaps;
1217 ddsa.ddsa_props = props;
1218 ddsa.ddsa_errors = errors;
1219
1220 if (error == 0) {
1221 error = dsl_sync_task(firstname, dsl_dataset_snapshot_check,
1222 dsl_dataset_snapshot_sync, &ddsa,
1223 fnvlist_num_pairs(snaps) * 3);
1224 }
1225
1226 if (suspended != NULL) {
1227 for (pair = nvlist_next_nvpair(suspended, NULL); pair != NULL;
1228 pair = nvlist_next_nvpair(suspended, pair)) {
1229 zil_resume((void *)(uintptr_t)
1230 fnvpair_value_uint64(pair));
1231 }
1232 fnvlist_free(suspended);
1233 }
1234
1235 return (error);
1236 }
1237
1238 typedef struct dsl_dataset_snapshot_tmp_arg {
1239 const char *ddsta_fsname;
1240 const char *ddsta_snapname;
1241 minor_t ddsta_cleanup_minor;
1242 const char *ddsta_htag;
1243 } dsl_dataset_snapshot_tmp_arg_t;
1244
1245 static int
1246 dsl_dataset_snapshot_tmp_check(void *arg, dmu_tx_t *tx)
1247 {
1248 dsl_dataset_snapshot_tmp_arg_t *ddsta = arg;
1249 dsl_pool_t *dp = dmu_tx_pool(tx);
1250 dsl_dataset_t *ds;
1251 int error;
1252
1253 error = dsl_dataset_hold(dp, ddsta->ddsta_fsname, FTAG, &ds);
1254 if (error != 0)
1255 return (error);
1256
1257 error = dsl_dataset_snapshot_check_impl(ds, ddsta->ddsta_snapname,
1258 tx, B_FALSE);
1259 if (error != 0) {
1260 dsl_dataset_rele(ds, FTAG);
1261 return (error);
1262 }
1263
1264 if (spa_version(dp->dp_spa) < SPA_VERSION_USERREFS) {
1265 dsl_dataset_rele(ds, FTAG);
1266 return (SET_ERROR(ENOTSUP));
1267 }
1268 error = dsl_dataset_user_hold_check_one(NULL, ddsta->ddsta_htag,
1269 B_TRUE, tx);
1270 if (error != 0) {
1271 dsl_dataset_rele(ds, FTAG);
1272 return (error);
1273 }
1274
1275 dsl_dataset_rele(ds, FTAG);
1276 return (0);
1277 }
1278
1279 static void
1280 dsl_dataset_snapshot_tmp_sync(void *arg, dmu_tx_t *tx)
1281 {
1282 dsl_dataset_snapshot_tmp_arg_t *ddsta = arg;
1283 dsl_pool_t *dp = dmu_tx_pool(tx);
1284 dsl_dataset_t *ds;
1285
1286 VERIFY0(dsl_dataset_hold(dp, ddsta->ddsta_fsname, FTAG, &ds));
1287
1288 dsl_dataset_snapshot_sync_impl(ds, ddsta->ddsta_snapname, tx);
1289 dsl_dataset_user_hold_sync_one(ds->ds_prev, ddsta->ddsta_htag,
1290 ddsta->ddsta_cleanup_minor, gethrestime_sec(), tx);
1291 dsl_destroy_snapshot_sync_impl(ds->ds_prev, B_TRUE, tx);
1292
1293 dsl_dataset_rele(ds, FTAG);
1294 }
1295
1296 int
1297 dsl_dataset_snapshot_tmp(const char *fsname, const char *snapname,
1298 minor_t cleanup_minor, const char *htag)
1299 {
1300 dsl_dataset_snapshot_tmp_arg_t ddsta;
1301 int error;
1302 spa_t *spa;
1303 boolean_t needsuspend;
1304 void *cookie;
1305
1306 ddsta.ddsta_fsname = fsname;
1307 ddsta.ddsta_snapname = snapname;
1308 ddsta.ddsta_cleanup_minor = cleanup_minor;
1309 ddsta.ddsta_htag = htag;
1310
1311 error = spa_open(fsname, &spa, FTAG);
1312 if (error != 0)
1313 return (error);
1314 needsuspend = (spa_version(spa) < SPA_VERSION_FAST_SNAP);
1315 spa_close(spa, FTAG);
1316
1317 if (needsuspend) {
1318 error = zil_suspend(fsname, &cookie);
1319 if (error != 0)
1320 return (error);
1321 }
1322
1323 error = dsl_sync_task(fsname, dsl_dataset_snapshot_tmp_check,
1324 dsl_dataset_snapshot_tmp_sync, &ddsta, 3);
1325
1326 if (needsuspend)
1327 zil_resume(cookie);
1328 return (error);
1329 }
1330
1331
1332 void
1333 dsl_dataset_sync(dsl_dataset_t *ds, zio_t *zio, dmu_tx_t *tx)
1334 {
1335 ASSERT(dmu_tx_is_syncing(tx));
1336 ASSERT(ds->ds_objset != NULL);
1337 ASSERT(ds->ds_phys->ds_next_snap_obj == 0);
1338
1339 /*
1340 * in case we had to change ds_fsid_guid when we opened it,
1341 * sync it out now.
1342 */
1343 dmu_buf_will_dirty(ds->ds_dbuf, tx);
1344 ds->ds_phys->ds_fsid_guid = ds->ds_fsid_guid;
1345
1346 dmu_objset_sync(ds->ds_objset, zio, tx);
1347 }
1348
1349 static void
1350 get_clones_stat(dsl_dataset_t *ds, nvlist_t *nv)
1351 {
1352 uint64_t count = 0;
1353 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
1354 zap_cursor_t zc;
1355 zap_attribute_t za;
1356 nvlist_t *propval = fnvlist_alloc();
1357 nvlist_t *val = fnvlist_alloc();
1358
1359 ASSERT(dsl_pool_config_held(ds->ds_dir->dd_pool));
1360
1361 /*
1362 * There may be missing entries in ds_next_clones_obj
1363 * due to a bug in a previous version of the code.
1364 * Only trust it if it has the right number of entries.
1365 */
1366 if (ds->ds_phys->ds_next_clones_obj != 0) {
1367 ASSERT0(zap_count(mos, ds->ds_phys->ds_next_clones_obj,
1368 &count));
1369 }
1370 if (count != ds->ds_phys->ds_num_children - 1)
1371 goto fail;
1372 for (zap_cursor_init(&zc, mos, ds->ds_phys->ds_next_clones_obj);
1373 zap_cursor_retrieve(&zc, &za) == 0;
1374 zap_cursor_advance(&zc)) {
1375 dsl_dataset_t *clone;
1376 char buf[ZFS_MAXNAMELEN];
1377 VERIFY0(dsl_dataset_hold_obj(ds->ds_dir->dd_pool,
1378 za.za_first_integer, FTAG, &clone));
1379 dsl_dir_name(clone->ds_dir, buf);
1380 fnvlist_add_boolean(val, buf);
1381 dsl_dataset_rele(clone, FTAG);
1382 }
1383 zap_cursor_fini(&zc);
1384 fnvlist_add_nvlist(propval, ZPROP_VALUE, val);
1385 fnvlist_add_nvlist(nv, zfs_prop_to_name(ZFS_PROP_CLONES), propval);
1386 fail:
1387 nvlist_free(val);
1388 nvlist_free(propval);
1389 }
1390
1391 void
1392 dsl_dataset_stats(dsl_dataset_t *ds, nvlist_t *nv)
1393 {
1394 dsl_pool_t *dp = ds->ds_dir->dd_pool;
1395 uint64_t refd, avail, uobjs, aobjs, ratio;
1396
1397 ASSERT(dsl_pool_config_held(dp));
1398
1399 ratio = ds->ds_phys->ds_compressed_bytes == 0 ? 100 :
1400 (ds->ds_phys->ds_uncompressed_bytes * 100 /
1401 ds->ds_phys->ds_compressed_bytes);
1402
1403 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFRATIO, ratio);
1404 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_LOGICALREFERENCED,
1405 ds->ds_phys->ds_uncompressed_bytes);
1406
1407 if (dsl_dataset_is_snapshot(ds)) {
1408 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_COMPRESSRATIO, ratio);
1409 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USED,
1410 ds->ds_phys->ds_unique_bytes);
1411 get_clones_stat(ds, nv);
1412 } else {
1413 dsl_dir_stats(ds->ds_dir, nv);
1414 }
1415
1416 dsl_dataset_space(ds, &refd, &avail, &uobjs, &aobjs);
1417 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_AVAILABLE, avail);
1418 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFERENCED, refd);
1419
1420 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATION,
1421 ds->ds_phys->ds_creation_time);
1422 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATETXG,
1423 ds->ds_phys->ds_creation_txg);
1424 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFQUOTA,
1425 ds->ds_quota);
1426 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFRESERVATION,
1427 ds->ds_reserved);
1428 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_GUID,
1429 ds->ds_phys->ds_guid);
1430 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_UNIQUE,
1431 ds->ds_phys->ds_unique_bytes);
1432 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_OBJSETID,
1433 ds->ds_object);
1434 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USERREFS,
1435 ds->ds_userrefs);
1436 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_DEFER_DESTROY,
1437 DS_IS_DEFER_DESTROY(ds) ? 1 : 0);
1438
1439 if (ds->ds_phys->ds_prev_snap_obj != 0) {
1440 uint64_t written, comp, uncomp;
1441 dsl_pool_t *dp = ds->ds_dir->dd_pool;
1442 dsl_dataset_t *prev;
1443
1444 int err = dsl_dataset_hold_obj(dp,
1445 ds->ds_phys->ds_prev_snap_obj, FTAG, &prev);
1446 if (err == 0) {
1447 err = dsl_dataset_space_written(prev, ds, &written,
1448 &comp, &uncomp);
1449 dsl_dataset_rele(prev, FTAG);
1450 if (err == 0) {
1451 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_WRITTEN,
1452 written);
1453 }
1454 }
1455 }
1456 }
1457
1458 void
1459 dsl_dataset_fast_stat(dsl_dataset_t *ds, dmu_objset_stats_t *stat)
1460 {
1461 dsl_pool_t *dp = ds->ds_dir->dd_pool;
1462 ASSERT(dsl_pool_config_held(dp));
1463
1464 stat->dds_creation_txg = ds->ds_phys->ds_creation_txg;
1465 stat->dds_inconsistent = ds->ds_phys->ds_flags & DS_FLAG_INCONSISTENT;
1466 stat->dds_guid = ds->ds_phys->ds_guid;
1467 stat->dds_origin[0] = '\0';
1468 if (dsl_dataset_is_snapshot(ds)) {
1469 stat->dds_is_snapshot = B_TRUE;
1470 stat->dds_num_clones = ds->ds_phys->ds_num_children - 1;
1471 } else {
1472 stat->dds_is_snapshot = B_FALSE;
1473 stat->dds_num_clones = 0;
1474
1475 if (dsl_dir_is_clone(ds->ds_dir)) {
1476 dsl_dataset_t *ods;
1477
1478 VERIFY0(dsl_dataset_hold_obj(dp,
1479 ds->ds_dir->dd_phys->dd_origin_obj, FTAG, &ods));
1480 dsl_dataset_name(ods, stat->dds_origin);
1481 dsl_dataset_rele(ods, FTAG);
1482 }
1483 }
1484 }
1485
1486 uint64_t
1487 dsl_dataset_fsid_guid(dsl_dataset_t *ds)
1488 {
1489 return (ds->ds_fsid_guid);
1490 }
1491
1492 void
1493 dsl_dataset_space(dsl_dataset_t *ds,
1494 uint64_t *refdbytesp, uint64_t *availbytesp,
1495 uint64_t *usedobjsp, uint64_t *availobjsp)
1496 {
1497 *refdbytesp = ds->ds_phys->ds_referenced_bytes;
1498 *availbytesp = dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE);
1499 if (ds->ds_reserved > ds->ds_phys->ds_unique_bytes)
1500 *availbytesp += ds->ds_reserved - ds->ds_phys->ds_unique_bytes;
1501 if (ds->ds_quota != 0) {
1502 /*
1503 * Adjust available bytes according to refquota
1504 */
1505 if (*refdbytesp < ds->ds_quota)
1506 *availbytesp = MIN(*availbytesp,
1507 ds->ds_quota - *refdbytesp);
1508 else
1509 *availbytesp = 0;
1510 }
1511 *usedobjsp = ds->ds_phys->ds_bp.blk_fill;
1512 *availobjsp = DN_MAX_OBJECT - *usedobjsp;
1513 }
1514
1515 boolean_t
1516 dsl_dataset_modified_since_snap(dsl_dataset_t *ds, dsl_dataset_t *snap)
1517 {
1518 dsl_pool_t *dp = ds->ds_dir->dd_pool;
1519
1520 ASSERT(dsl_pool_config_held(dp));
1521 if (snap == NULL)
1522 return (B_FALSE);
1523 if (ds->ds_phys->ds_bp.blk_birth >
1524 snap->ds_phys->ds_creation_txg) {
1525 objset_t *os, *os_snap;
1526 /*
1527 * It may be that only the ZIL differs, because it was
1528 * reset in the head. Don't count that as being
1529 * modified.
1530 */
1531 if (dmu_objset_from_ds(ds, &os) != 0)
1532 return (B_TRUE);
1533 if (dmu_objset_from_ds(snap, &os_snap) != 0)
1534 return (B_TRUE);
1535 return (bcmp(&os->os_phys->os_meta_dnode,
1536 &os_snap->os_phys->os_meta_dnode,
1537 sizeof (os->os_phys->os_meta_dnode)) != 0);
1538 }
1539 return (B_FALSE);
1540 }
1541
1542 typedef struct dsl_dataset_rename_snapshot_arg {
1543 const char *ddrsa_fsname;
1544 const char *ddrsa_oldsnapname;
1545 const char *ddrsa_newsnapname;
1546 boolean_t ddrsa_recursive;
1547 dmu_tx_t *ddrsa_tx;
1548 } dsl_dataset_rename_snapshot_arg_t;
1549
1550 /* ARGSUSED */
1551 static int
1552 dsl_dataset_rename_snapshot_check_impl(dsl_pool_t *dp,
1553 dsl_dataset_t *hds, void *arg)
1554 {
1555 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg;
1556 int error;
1557 uint64_t val;
1558
1559 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_oldsnapname, &val);
1560 if (error != 0) {
1561 /* ignore nonexistent snapshots */
1562 return (error == ENOENT ? 0 : error);
1563 }
1564
1565 /* new name should not exist */
1566 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_newsnapname, &val);
1567 if (error == 0)
1568 error = SET_ERROR(EEXIST);
1569 else if (error == ENOENT)
1570 error = 0;
1571
1572 /* dataset name + 1 for the "@" + the new snapshot name must fit */
1573 if (dsl_dir_namelen(hds->ds_dir) + 1 +
1574 strlen(ddrsa->ddrsa_newsnapname) >= MAXNAMELEN)
1575 error = SET_ERROR(ENAMETOOLONG);
1576
1577 return (error);
1578 }
1579
1580 static int
1581 dsl_dataset_rename_snapshot_check(void *arg, dmu_tx_t *tx)
1582 {
1583 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg;
1584 dsl_pool_t *dp = dmu_tx_pool(tx);
1585 dsl_dataset_t *hds;
1586 int error;
1587
1588 error = dsl_dataset_hold(dp, ddrsa->ddrsa_fsname, FTAG, &hds);
1589 if (error != 0)
1590 return (error);
1591
1592 if (ddrsa->ddrsa_recursive) {
1593 error = dmu_objset_find_dp(dp, hds->ds_dir->dd_object,
1594 dsl_dataset_rename_snapshot_check_impl, ddrsa,
1595 DS_FIND_CHILDREN);
1596 } else {
1597 error = dsl_dataset_rename_snapshot_check_impl(dp, hds, ddrsa);
1598 }
1599 dsl_dataset_rele(hds, FTAG);
1600 return (error);
1601 }
1602
1603 static int
1604 dsl_dataset_rename_snapshot_sync_impl(dsl_pool_t *dp,
1605 dsl_dataset_t *hds, void *arg)
1606 {
1607 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg;
1608 dsl_dataset_t *ds;
1609 uint64_t val;
1610 dmu_tx_t *tx = ddrsa->ddrsa_tx;
1611 int error;
1612
1613 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_oldsnapname, &val);
1614 ASSERT(error == 0 || error == ENOENT);
1615 if (error == ENOENT) {
1616 /* ignore nonexistent snapshots */
1617 return (0);
1618 }
1619
1620 VERIFY0(dsl_dataset_hold_obj(dp, val, FTAG, &ds));
1621
1622 /* log before we change the name */
1623 spa_history_log_internal_ds(ds, "rename", tx,
1624 "-> @%s", ddrsa->ddrsa_newsnapname);
1625
1626 VERIFY0(dsl_dataset_snap_remove(hds, ddrsa->ddrsa_oldsnapname, tx));
1627 mutex_enter(&ds->ds_lock);
1628 (void) strcpy(ds->ds_snapname, ddrsa->ddrsa_newsnapname);
1629 mutex_exit(&ds->ds_lock);
1630 VERIFY0(zap_add(dp->dp_meta_objset, hds->ds_phys->ds_snapnames_zapobj,
1631 ds->ds_snapname, 8, 1, &ds->ds_object, tx));
1632
1633 dsl_dataset_rele(ds, FTAG);
1634 return (0);
1635 }
1636
1637 static void
1638 dsl_dataset_rename_snapshot_sync(void *arg, dmu_tx_t *tx)
1639 {
1640 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg;
1641 dsl_pool_t *dp = dmu_tx_pool(tx);
1642 dsl_dataset_t *hds;
1643
1644 VERIFY0(dsl_dataset_hold(dp, ddrsa->ddrsa_fsname, FTAG, &hds));
1645 ddrsa->ddrsa_tx = tx;
1646 if (ddrsa->ddrsa_recursive) {
1647 VERIFY0(dmu_objset_find_dp(dp, hds->ds_dir->dd_object,
1648 dsl_dataset_rename_snapshot_sync_impl, ddrsa,
1649 DS_FIND_CHILDREN));
1650 } else {
1651 VERIFY0(dsl_dataset_rename_snapshot_sync_impl(dp, hds, ddrsa));
1652 }
1653 dsl_dataset_rele(hds, FTAG);
1654 }
1655
1656 int
1657 dsl_dataset_rename_snapshot(const char *fsname,
1658 const char *oldsnapname, const char *newsnapname, boolean_t recursive)
1659 {
1660 dsl_dataset_rename_snapshot_arg_t ddrsa;
1661
1662 ddrsa.ddrsa_fsname = fsname;
1663 ddrsa.ddrsa_oldsnapname = oldsnapname;
1664 ddrsa.ddrsa_newsnapname = newsnapname;
1665 ddrsa.ddrsa_recursive = recursive;
1666
1667 return (dsl_sync_task(fsname, dsl_dataset_rename_snapshot_check,
1668 dsl_dataset_rename_snapshot_sync, &ddrsa, 1));
1669 }
1670
1671 /*
1672 * If we're doing an ownership handoff, we need to make sure that there is
1673 * only one long hold on the dataset. We're not allowed to change anything here
1674 * so we don't permanently release the long hold or regular hold here. We want
1675 * to do this only when syncing to avoid the dataset unexpectedly going away
1676 * when we release the long hold.
1677 */
1678 static int
1679 dsl_dataset_handoff_check(dsl_dataset_t *ds, void *owner, dmu_tx_t *tx)
1680 {
1681 boolean_t held;
1682
1683 if (!dmu_tx_is_syncing(tx))
1684 return (0);
1685
1686 if (owner != NULL) {
1687 VERIFY3P(ds->ds_owner, ==, owner);
1688 dsl_dataset_long_rele(ds, owner);
1689 }
1690
1691 held = dsl_dataset_long_held(ds);
1692
1693 if (owner != NULL)
1694 dsl_dataset_long_hold(ds, owner);
1695
1696 if (held)
1697 return (SET_ERROR(EBUSY));
1698
1699 return (0);
1700 }
1701
1702 typedef struct dsl_dataset_rollback_arg {
1703 const char *ddra_fsname;
1704 void *ddra_owner;
1705 nvlist_t *ddra_result;
1706 } dsl_dataset_rollback_arg_t;
1707
1708 static int
1709 dsl_dataset_rollback_check(void *arg, dmu_tx_t *tx)
1710 {
1711 dsl_dataset_rollback_arg_t *ddra = arg;
1712 dsl_pool_t *dp = dmu_tx_pool(tx);
1713 dsl_dataset_t *ds;
1714 int64_t unused_refres_delta;
1715 int error;
1716
1717 error = dsl_dataset_hold(dp, ddra->ddra_fsname, FTAG, &ds);
1718 if (error != 0)
1719 return (error);
1720
1721 /* must not be a snapshot */
1722 if (dsl_dataset_is_snapshot(ds)) {
1723 dsl_dataset_rele(ds, FTAG);
1724 return (SET_ERROR(EINVAL));
1725 }
1726
1727 /* must have a most recent snapshot */
1728 if (ds->ds_phys->ds_prev_snap_txg < TXG_INITIAL) {
1729 dsl_dataset_rele(ds, FTAG);
1730 return (SET_ERROR(EINVAL));
1731 }
1732
1733 /* must not have any bookmarks after the most recent snapshot */
1734 nvlist_t *proprequest = fnvlist_alloc();
1735 fnvlist_add_boolean(proprequest, zfs_prop_to_name(ZFS_PROP_CREATETXG));
1736 nvlist_t *bookmarks = fnvlist_alloc();
1737 error = dsl_get_bookmarks_impl(ds, proprequest, bookmarks);
1738 fnvlist_free(proprequest);
1739 if (error != 0)
1740 return (error);
1741 for (nvpair_t *pair = nvlist_next_nvpair(bookmarks, NULL);
1742 pair != NULL; pair = nvlist_next_nvpair(bookmarks, pair)) {
1743 nvlist_t *valuenv =
1744 fnvlist_lookup_nvlist(fnvpair_value_nvlist(pair),
1745 zfs_prop_to_name(ZFS_PROP_CREATETXG));
1746 uint64_t createtxg = fnvlist_lookup_uint64(valuenv, "value");
1747 if (createtxg > ds->ds_phys->ds_prev_snap_txg) {
1748 fnvlist_free(bookmarks);
1749 dsl_dataset_rele(ds, FTAG);
1750 return (SET_ERROR(EEXIST));
1751 }
1752 }
1753 fnvlist_free(bookmarks);
1754
1755 error = dsl_dataset_handoff_check(ds, ddra->ddra_owner, tx);
1756 if (error != 0) {
1757 dsl_dataset_rele(ds, FTAG);
1758 return (error);
1759 }
1760
1761 /*
1762 * Check if the snap we are rolling back to uses more than
1763 * the refquota.
1764 */
1765 if (ds->ds_quota != 0 &&
1766 ds->ds_prev->ds_phys->ds_referenced_bytes > ds->ds_quota) {
1767 dsl_dataset_rele(ds, FTAG);
1768 return (SET_ERROR(EDQUOT));
1769 }
1770
1771 /*
1772 * When we do the clone swap, we will temporarily use more space
1773 * due to the refreservation (the head will no longer have any
1774 * unique space, so the entire amount of the refreservation will need
1775 * to be free). We will immediately destroy the clone, freeing
1776 * this space, but the freeing happens over many txg's.
1777 */
1778 unused_refres_delta = (int64_t)MIN(ds->ds_reserved,
1779 ds->ds_phys->ds_unique_bytes);
1780
1781 if (unused_refres_delta > 0 &&
1782 unused_refres_delta >
1783 dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE)) {
1784 dsl_dataset_rele(ds, FTAG);
1785 return (SET_ERROR(ENOSPC));
1786 }
1787
1788 dsl_dataset_rele(ds, FTAG);
1789 return (0);
1790 }
1791
1792 static void
1793 dsl_dataset_rollback_sync(void *arg, dmu_tx_t *tx)
1794 {
1795 dsl_dataset_rollback_arg_t *ddra = arg;
1796 dsl_pool_t *dp = dmu_tx_pool(tx);
1797 dsl_dataset_t *ds, *clone;
1798 uint64_t cloneobj;
1799 char namebuf[ZFS_MAXNAMELEN];
1800
1801 VERIFY0(dsl_dataset_hold(dp, ddra->ddra_fsname, FTAG, &ds));
1802
1803 dsl_dataset_name(ds->ds_prev, namebuf);
1804 fnvlist_add_string(ddra->ddra_result, "target", namebuf);
1805
1806 cloneobj = dsl_dataset_create_sync(ds->ds_dir, "%rollback",
1807 ds->ds_prev, DS_CREATE_FLAG_NODIRTY, kcred, tx);
1808
1809 VERIFY0(dsl_dataset_hold_obj(dp, cloneobj, FTAG, &clone));
1810
1811 dsl_dataset_clone_swap_sync_impl(clone, ds, tx);
1812 dsl_dataset_zero_zil(ds, tx);
1813
1814 dsl_destroy_head_sync_impl(clone, tx);
1815
1816 dsl_dataset_rele(clone, FTAG);
1817 dsl_dataset_rele(ds, FTAG);
1818 }
1819
1820 /*
1821 * Rolls back the given filesystem or volume to the most recent snapshot.
1822 * The name of the most recent snapshot will be returned under key "target"
1823 * in the result nvlist.
1824 *
1825 * If owner != NULL:
1826 * - The existing dataset MUST be owned by the specified owner at entry
1827 * - Upon return, dataset will still be held by the same owner, whether we
1828 * succeed or not.
1829 *
1830 * This mode is required any time the existing filesystem is mounted. See
1831 * notes above zfs_suspend_fs() for further details.
1832 */
1833 int
1834 dsl_dataset_rollback(const char *fsname, void *owner, nvlist_t *result)
1835 {
1836 dsl_dataset_rollback_arg_t ddra;
1837
1838 ddra.ddra_fsname = fsname;
1839 ddra.ddra_owner = owner;
1840 ddra.ddra_result = result;
1841
1842 return (dsl_sync_task(fsname, dsl_dataset_rollback_check,
1843 dsl_dataset_rollback_sync, &ddra, 1));
1844 }
1845
1846 struct promotenode {
1847 list_node_t link;
1848 dsl_dataset_t *ds;
1849 };
1850
1851 typedef struct dsl_dataset_promote_arg {
1852 const char *ddpa_clonename;
1853 dsl_dataset_t *ddpa_clone;
1854 list_t shared_snaps, origin_snaps, clone_snaps;
1855 dsl_dataset_t *origin_origin; /* origin of the origin */
1856 uint64_t used, comp, uncomp, unique, cloneusedsnap, originusedsnap;
1857 char *err_ds;
1858 } dsl_dataset_promote_arg_t;
1859
1860 static int snaplist_space(list_t *l, uint64_t mintxg, uint64_t *spacep);
1861 static int promote_hold(dsl_dataset_promote_arg_t *ddpa, dsl_pool_t *dp,
1862 void *tag);
1863 static void promote_rele(dsl_dataset_promote_arg_t *ddpa, void *tag);
1864
1865 static int
1866 dsl_dataset_promote_check(void *arg, dmu_tx_t *tx)
1867 {
1868 dsl_dataset_promote_arg_t *ddpa = arg;
1869 dsl_pool_t *dp = dmu_tx_pool(tx);
1870 dsl_dataset_t *hds;
1871 struct promotenode *snap;
1872 dsl_dataset_t *origin_ds;
1873 int err;
1874 uint64_t unused;
1875
1876 err = promote_hold(ddpa, dp, FTAG);
1877 if (err != 0)
1878 return (err);
1879
1880 hds = ddpa->ddpa_clone;
1881
1882 if (hds->ds_phys->ds_flags & DS_FLAG_NOPROMOTE) {
1883 promote_rele(ddpa, FTAG);
1884 return (SET_ERROR(EXDEV));
1885 }
1886
1887 /*
1888 * Compute and check the amount of space to transfer. Since this is
1889 * so expensive, don't do the preliminary check.
1890 */
1891 if (!dmu_tx_is_syncing(tx)) {
1892 promote_rele(ddpa, FTAG);
1893 return (0);
1894 }
1895
1896 snap = list_head(&ddpa->shared_snaps);
1897 origin_ds = snap->ds;
1898
1899 /* compute origin's new unique space */
1900 snap = list_tail(&ddpa->clone_snaps);
1901 ASSERT3U(snap->ds->ds_phys->ds_prev_snap_obj, ==, origin_ds->ds_object);
1902 dsl_deadlist_space_range(&snap->ds->ds_deadlist,
1903 origin_ds->ds_phys->ds_prev_snap_txg, UINT64_MAX,
1904 &ddpa->unique, &unused, &unused);
1905
1906 /*
1907 * Walk the snapshots that we are moving
1908 *
1909 * Compute space to transfer. Consider the incremental changes
1910 * to used by each snapshot:
1911 * (my used) = (prev's used) + (blocks born) - (blocks killed)
1912 * So each snapshot gave birth to:
1913 * (blocks born) = (my used) - (prev's used) + (blocks killed)
1914 * So a sequence would look like:
1915 * (uN - u(N-1) + kN) + ... + (u1 - u0 + k1) + (u0 - 0 + k0)
1916 * Which simplifies to:
1917 * uN + kN + kN-1 + ... + k1 + k0
1918 * Note however, if we stop before we reach the ORIGIN we get:
1919 * uN + kN + kN-1 + ... + kM - uM-1
1920 */
1921 ddpa->used = origin_ds->ds_phys->ds_referenced_bytes;
1922 ddpa->comp = origin_ds->ds_phys->ds_compressed_bytes;
1923 ddpa->uncomp = origin_ds->ds_phys->ds_uncompressed_bytes;
1924 for (snap = list_head(&ddpa->shared_snaps); snap;
1925 snap = list_next(&ddpa->shared_snaps, snap)) {
1926 uint64_t val, dlused, dlcomp, dluncomp;
1927 dsl_dataset_t *ds = snap->ds;
1928
1929 /*
1930 * If there are long holds, we won't be able to evict
1931 * the objset.
1932 */
1933 if (dsl_dataset_long_held(ds)) {
1934 err = SET_ERROR(EBUSY);
1935 goto out;
1936 }
1937
1938 /* Check that the snapshot name does not conflict */
1939 VERIFY0(dsl_dataset_get_snapname(ds));
1940 err = dsl_dataset_snap_lookup(hds, ds->ds_snapname, &val);
1941 if (err == 0) {
1942 (void) strcpy(ddpa->err_ds, snap->ds->ds_snapname);
1943 err = SET_ERROR(EEXIST);
1944 goto out;
1945 }
1946 if (err != ENOENT)
1947 goto out;
1948
1949 /* The very first snapshot does not have a deadlist */
1950 if (ds->ds_phys->ds_prev_snap_obj == 0)
1951 continue;
1952
1953 dsl_deadlist_space(&ds->ds_deadlist,
1954 &dlused, &dlcomp, &dluncomp);
1955 ddpa->used += dlused;
1956 ddpa->comp += dlcomp;
1957 ddpa->uncomp += dluncomp;
1958 }
1959
1960 /*
1961 * If we are a clone of a clone then we never reached ORIGIN,
1962 * so we need to subtract out the clone origin's used space.
1963 */
1964 if (ddpa->origin_origin) {
1965 ddpa->used -= ddpa->origin_origin->ds_phys->ds_referenced_bytes;
1966 ddpa->comp -= ddpa->origin_origin->ds_phys->ds_compressed_bytes;
1967 ddpa->uncomp -=
1968 ddpa->origin_origin->ds_phys->ds_uncompressed_bytes;
1969 }
1970
1971 /* Check that there is enough space here */
1972 err = dsl_dir_transfer_possible(origin_ds->ds_dir, hds->ds_dir,
1973 ddpa->used);
1974 if (err != 0)
1975 goto out;
1976
1977 /*
1978 * Compute the amounts of space that will be used by snapshots
1979 * after the promotion (for both origin and clone). For each,
1980 * it is the amount of space that will be on all of their
1981 * deadlists (that was not born before their new origin).
1982 */
1983 if (hds->ds_dir->dd_phys->dd_flags & DD_FLAG_USED_BREAKDOWN) {
1984 uint64_t space;
1985
1986 /*
1987 * Note, typically this will not be a clone of a clone,
1988 * so dd_origin_txg will be < TXG_INITIAL, so
1989 * these snaplist_space() -> dsl_deadlist_space_range()
1990 * calls will be fast because they do not have to
1991 * iterate over all bps.
1992 */
1993 snap = list_head(&ddpa->origin_snaps);
1994 err = snaplist_space(&ddpa->shared_snaps,
1995 snap->ds->ds_dir->dd_origin_txg, &ddpa->cloneusedsnap);
1996 if (err != 0)
1997 goto out;
1998
1999 err = snaplist_space(&ddpa->clone_snaps,
2000 snap->ds->ds_dir->dd_origin_txg, &space);
2001 if (err != 0)
2002 goto out;
2003 ddpa->cloneusedsnap += space;
2004 }
2005 if (origin_ds->ds_dir->dd_phys->dd_flags & DD_FLAG_USED_BREAKDOWN) {
2006 err = snaplist_space(&ddpa->origin_snaps,
2007 origin_ds->ds_phys->ds_creation_txg, &ddpa->originusedsnap);
2008 if (err != 0)
2009 goto out;
2010 }
2011
2012 out:
2013 promote_rele(ddpa, FTAG);
2014 return (err);
2015 }
2016
2017 static void
2018 dsl_dataset_promote_sync(void *arg, dmu_tx_t *tx)
2019 {
2020 dsl_dataset_promote_arg_t *ddpa = arg;
2021 dsl_pool_t *dp = dmu_tx_pool(tx);
2022 dsl_dataset_t *hds;
2023 struct promotenode *snap;
2024 dsl_dataset_t *origin_ds;
2025 dsl_dataset_t *origin_head;
2026 dsl_dir_t *dd;
2027 dsl_dir_t *odd = NULL;
2028 uint64_t oldnext_obj;
2029 int64_t delta;
2030
2031 VERIFY0(promote_hold(ddpa, dp, FTAG));
2032 hds = ddpa->ddpa_clone;
2033
2034 ASSERT0(hds->ds_phys->ds_flags & DS_FLAG_NOPROMOTE);
2035
2036 snap = list_head(&ddpa->shared_snaps);
2037 origin_ds = snap->ds;
2038 dd = hds->ds_dir;
2039
2040 snap = list_head(&ddpa->origin_snaps);
2041 origin_head = snap->ds;
2042
2043 /*
2044 * We need to explicitly open odd, since origin_ds's dd will be
2045 * changing.
2046 */
2047 VERIFY0(dsl_dir_hold_obj(dp, origin_ds->ds_dir->dd_object,
2048 NULL, FTAG, &odd));
2049
2050 /* change origin's next snap */
2051 dmu_buf_will_dirty(origin_ds->ds_dbuf, tx);
2052 oldnext_obj = origin_ds->ds_phys->ds_next_snap_obj;
2053 snap = list_tail(&ddpa->clone_snaps);
2054 ASSERT3U(snap->ds->ds_phys->ds_prev_snap_obj, ==, origin_ds->ds_object);
2055 origin_ds->ds_phys->ds_next_snap_obj = snap->ds->ds_object;
2056
2057 /* change the origin's next clone */
2058 if (origin_ds->ds_phys->ds_next_clones_obj) {
2059 dsl_dataset_remove_from_next_clones(origin_ds,
2060 snap->ds->ds_object, tx);
2061 VERIFY0(zap_add_int(dp->dp_meta_objset,
2062 origin_ds->ds_phys->ds_next_clones_obj,
2063 oldnext_obj, tx));
2064 }
2065
2066 /* change origin */
2067 dmu_buf_will_dirty(dd->dd_dbuf, tx);
2068 ASSERT3U(dd->dd_phys->dd_origin_obj, ==, origin_ds->ds_object);
2069 dd->dd_phys->dd_origin_obj = odd->dd_phys->dd_origin_obj;
2070 dd->dd_origin_txg = origin_head->ds_dir->dd_origin_txg;
2071 dmu_buf_will_dirty(odd->dd_dbuf, tx);
2072 odd->dd_phys->dd_origin_obj = origin_ds->ds_object;
2073 origin_head->ds_dir->dd_origin_txg =
2074 origin_ds->ds_phys->ds_creation_txg;
2075
2076 /* change dd_clone entries */
2077 if (spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) {
2078 VERIFY0(zap_remove_int(dp->dp_meta_objset,
2079 odd->dd_phys->dd_clones, hds->ds_object, tx));
2080 VERIFY0(zap_add_int(dp->dp_meta_objset,
2081 ddpa->origin_origin->ds_dir->dd_phys->dd_clones,
2082 hds->ds_object, tx));
2083
2084 VERIFY0(zap_remove_int(dp->dp_meta_objset,
2085 ddpa->origin_origin->ds_dir->dd_phys->dd_clones,
2086 origin_head->ds_object, tx));
2087 if (dd->dd_phys->dd_clones == 0) {
2088 dd->dd_phys->dd_clones = zap_create(dp->dp_meta_objset,
2089 DMU_OT_DSL_CLONES, DMU_OT_NONE, 0, tx);
2090 }
2091 VERIFY0(zap_add_int(dp->dp_meta_objset,
2092 dd->dd_phys->dd_clones, origin_head->ds_object, tx));
2093 }
2094
2095 /* move snapshots to this dir */
2096 for (snap = list_head(&ddpa->shared_snaps); snap;
2097 snap = list_next(&ddpa->shared_snaps, snap)) {
2098 dsl_dataset_t *ds = snap->ds;
2099
2100 /*
2101 * Property callbacks are registered to a particular
2102 * dsl_dir. Since ours is changing, evict the objset
2103 * so that they will be unregistered from the old dsl_dir.
2104 */
2105 if (ds->ds_objset) {
2106 dmu_objset_evict(ds->ds_objset);
2107 ds->ds_objset = NULL;
2108 }
2109
2110 /* move snap name entry */
2111 VERIFY0(dsl_dataset_get_snapname(ds));
2112 VERIFY0(dsl_dataset_snap_remove(origin_head,
2113 ds->ds_snapname, tx));
2114 VERIFY0(zap_add(dp->dp_meta_objset,
2115 hds->ds_phys->ds_snapnames_zapobj, ds->ds_snapname,
2116 8, 1, &ds->ds_object, tx));
2117
2118 /* change containing dsl_dir */
2119 dmu_buf_will_dirty(ds->ds_dbuf, tx);
2120 ASSERT3U(ds->ds_phys->ds_dir_obj, ==, odd->dd_object);
2121 ds->ds_phys->ds_dir_obj = dd->dd_object;
2122 ASSERT3P(ds->ds_dir, ==, odd);
2123 dsl_dir_rele(ds->ds_dir, ds);
2124 VERIFY0(dsl_dir_hold_obj(dp, dd->dd_object,
2125 NULL, ds, &ds->ds_dir));
2126
2127 /* move any clone references */
2128 if (ds->ds_phys->ds_next_clones_obj &&
2129 spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) {
2130 zap_cursor_t zc;
2131 zap_attribute_t za;
2132
2133 for (zap_cursor_init(&zc, dp->dp_meta_objset,
2134 ds->ds_phys->ds_next_clones_obj);
2135 zap_cursor_retrieve(&zc, &za) == 0;
2136 zap_cursor_advance(&zc)) {
2137 dsl_dataset_t *cnds;
2138 uint64_t o;
2139
2140 if (za.za_first_integer == oldnext_obj) {
2141 /*
2142 * We've already moved the
2143 * origin's reference.
2144 */
2145 continue;
2146 }
2147
2148 VERIFY0(dsl_dataset_hold_obj(dp,
2149 za.za_first_integer, FTAG, &cnds));
2150 o = cnds->ds_dir->dd_phys->dd_head_dataset_obj;
2151
2152 VERIFY0(zap_remove_int(dp->dp_meta_objset,
2153 odd->dd_phys->dd_clones, o, tx));
2154 VERIFY0(zap_add_int(dp->dp_meta_objset,
2155 dd->dd_phys->dd_clones, o, tx));
2156 dsl_dataset_rele(cnds, FTAG);
2157 }
2158 zap_cursor_fini(&zc);
2159 }
2160
2161 ASSERT(!dsl_prop_hascb(ds));
2162 }
2163
2164 /*
2165 * Change space accounting.
2166 * Note, pa->*usedsnap and dd_used_breakdown[SNAP] will either
2167 * both be valid, or both be 0 (resulting in delta == 0). This
2168 * is true for each of {clone,origin} independently.
2169 */
2170
2171 delta = ddpa->cloneusedsnap -
2172 dd->dd_phys->dd_used_breakdown[DD_USED_SNAP];
2173 ASSERT3S(delta, >=, 0);
2174 ASSERT3U(ddpa->used, >=, delta);
2175 dsl_dir_diduse_space(dd, DD_USED_SNAP, delta, 0, 0, tx);
2176 dsl_dir_diduse_space(dd, DD_USED_HEAD,
2177 ddpa->used - delta, ddpa->comp, ddpa->uncomp, tx);
2178
2179 delta = ddpa->originusedsnap -
2180 odd->dd_phys->dd_used_breakdown[DD_USED_SNAP];
2181 ASSERT3S(delta, <=, 0);
2182 ASSERT3U(ddpa->used, >=, -delta);
2183 dsl_dir_diduse_space(odd, DD_USED_SNAP, delta, 0, 0, tx);
2184 dsl_dir_diduse_space(odd, DD_USED_HEAD,
2185 -ddpa->used - delta, -ddpa->comp, -ddpa->uncomp, tx);
2186
2187 origin_ds->ds_phys->ds_unique_bytes = ddpa->unique;
2188
2189 /* log history record */
2190 spa_history_log_internal_ds(hds, "promote", tx, "");
2191
2192 dsl_dir_rele(odd, FTAG);
2193 promote_rele(ddpa, FTAG);
2194 }
2195
2196 /*
2197 * Make a list of dsl_dataset_t's for the snapshots between first_obj
2198 * (exclusive) and last_obj (inclusive). The list will be in reverse
2199 * order (last_obj will be the list_head()). If first_obj == 0, do all
2200 * snapshots back to this dataset's origin.
2201 */
2202 static int
2203 snaplist_make(dsl_pool_t *dp,
2204 uint64_t first_obj, uint64_t last_obj, list_t *l, void *tag)
2205 {
2206 uint64_t obj = last_obj;
2207
2208 list_create(l, sizeof (struct promotenode),
2209 offsetof(struct promotenode, link));
2210
2211 while (obj != first_obj) {
2212 dsl_dataset_t *ds;
2213 struct promotenode *snap;
2214 int err;
2215
2216 err = dsl_dataset_hold_obj(dp, obj, tag, &ds);
2217 ASSERT(err != ENOENT);
2218 if (err != 0)
2219 return (err);
2220
2221 if (first_obj == 0)
2222 first_obj = ds->ds_dir->dd_phys->dd_origin_obj;
2223
2224 snap = kmem_alloc(sizeof (*snap), KM_SLEEP);
2225 snap->ds = ds;
2226 list_insert_tail(l, snap);
2227 obj = ds->ds_phys->ds_prev_snap_obj;
2228 }
2229
2230 return (0);
2231 }
2232
2233 static int
2234 snaplist_space(list_t *l, uint64_t mintxg, uint64_t *spacep)
2235 {
2236 struct promotenode *snap;
2237
2238 *spacep = 0;
2239 for (snap = list_head(l); snap; snap = list_next(l, snap)) {
2240 uint64_t used, comp, uncomp;
2241 dsl_deadlist_space_range(&snap->ds->ds_deadlist,
2242 mintxg, UINT64_MAX, &used, &comp, &uncomp);
2243 *spacep += used;
2244 }
2245 return (0);
2246 }
2247
2248 static void
2249 snaplist_destroy(list_t *l, void *tag)
2250 {
2251 struct promotenode *snap;
2252
2253 if (l == NULL || !list_link_active(&l->list_head))
2254 return;
2255
2256 while ((snap = list_tail(l)) != NULL) {
2257 list_remove(l, snap);
2258 dsl_dataset_rele(snap->ds, tag);
2259 kmem_free(snap, sizeof (*snap));
2260 }
2261 list_destroy(l);
2262 }
2263
2264 static int
2265 promote_hold(dsl_dataset_promote_arg_t *ddpa, dsl_pool_t *dp, void *tag)
2266 {
2267 int error;
2268 dsl_dir_t *dd;
2269 struct promotenode *snap;
2270
2271 error = dsl_dataset_hold(dp, ddpa->ddpa_clonename, tag,
2272 &ddpa->ddpa_clone);
2273 if (error != 0)
2274 return (error);
2275 dd = ddpa->ddpa_clone->ds_dir;
2276
2277 if (dsl_dataset_is_snapshot(ddpa->ddpa_clone) ||
2278 !dsl_dir_is_clone(dd)) {
2279 dsl_dataset_rele(ddpa->ddpa_clone, tag);
2280 return (SET_ERROR(EINVAL));
2281 }
2282
2283 error = snaplist_make(dp, 0, dd->dd_phys->dd_origin_obj,
2284 &ddpa->shared_snaps, tag);
2285 if (error != 0)
2286 goto out;
2287
2288 error = snaplist_make(dp, 0, ddpa->ddpa_clone->ds_object,
2289 &ddpa->clone_snaps, tag);
2290 if (error != 0)
2291 goto out;
2292
2293 snap = list_head(&ddpa->shared_snaps);
2294 ASSERT3U(snap->ds->ds_object, ==, dd->dd_phys->dd_origin_obj);
2295 error = snaplist_make(dp, dd->dd_phys->dd_origin_obj,
2296 snap->ds->ds_dir->dd_phys->dd_head_dataset_obj,
2297 &ddpa->origin_snaps, tag);
2298 if (error != 0)
2299 goto out;
2300
2301 if (snap->ds->ds_dir->dd_phys->dd_origin_obj != 0) {
2302 error = dsl_dataset_hold_obj(dp,
2303 snap->ds->ds_dir->dd_phys->dd_origin_obj,
2304 tag, &ddpa->origin_origin);
2305 if (error != 0)
2306 goto out;
2307 }
2308 out:
2309 if (error != 0)
2310 promote_rele(ddpa, tag);
2311 return (error);
2312 }
2313
2314 static void
2315 promote_rele(dsl_dataset_promote_arg_t *ddpa, void *tag)
2316 {
2317 snaplist_destroy(&ddpa->shared_snaps, tag);
2318 snaplist_destroy(&ddpa->clone_snaps, tag);
2319 snaplist_destroy(&ddpa->origin_snaps, tag);
2320 if (ddpa->origin_origin != NULL)
2321 dsl_dataset_rele(ddpa->origin_origin, tag);
2322 dsl_dataset_rele(ddpa->ddpa_clone, tag);
2323 }
2324
2325 /*
2326 * Promote a clone.
2327 *
2328 * If it fails due to a conflicting snapshot name, "conflsnap" will be filled
2329 * in with the name. (It must be at least MAXNAMELEN bytes long.)
2330 */
2331 int
2332 dsl_dataset_promote(const char *name, char *conflsnap)
2333 {
2334 dsl_dataset_promote_arg_t ddpa = { 0 };
2335 uint64_t numsnaps;
2336 int error;
2337 objset_t *os;
2338
2339 /*
2340 * We will modify space proportional to the number of
2341 * snapshots. Compute numsnaps.
2342 */
2343 error = dmu_objset_hold(name, FTAG, &os);
2344 if (error != 0)
2345 return (error);
2346 error = zap_count(dmu_objset_pool(os)->dp_meta_objset,
2347 dmu_objset_ds(os)->ds_phys->ds_snapnames_zapobj, &numsnaps);
2348 dmu_objset_rele(os, FTAG);
2349 if (error != 0)
2350 return (error);
2351
2352 ddpa.ddpa_clonename = name;
2353 ddpa.err_ds = conflsnap;
2354
2355 return (dsl_sync_task(name, dsl_dataset_promote_check,
2356 dsl_dataset_promote_sync, &ddpa, 2 + numsnaps));
2357 }
2358
2359 int
2360 dsl_dataset_clone_swap_check_impl(dsl_dataset_t *clone,
2361 dsl_dataset_t *origin_head, boolean_t force, void *owner, dmu_tx_t *tx)
2362 {
2363 int64_t unused_refres_delta;
2364
2365 /* they should both be heads */
2366 if (dsl_dataset_is_snapshot(clone) ||
2367 dsl_dataset_is_snapshot(origin_head))
2368 return (SET_ERROR(EINVAL));
2369
2370 /* if we are not forcing, the branch point should be just before them */
2371 if (!force && clone->ds_prev != origin_head->ds_prev)
2372 return (SET_ERROR(EINVAL));
2373
2374 /* clone should be the clone (unless they are unrelated) */
2375 if (clone->ds_prev != NULL &&
2376 clone->ds_prev != clone->ds_dir->dd_pool->dp_origin_snap &&
2377 origin_head->ds_dir != clone->ds_prev->ds_dir)
2378 return (SET_ERROR(EINVAL));
2379
2380 /* the clone should be a child of the origin */
2381 if (clone->ds_dir->dd_parent != origin_head->ds_dir)
2382 return (SET_ERROR(EINVAL));
2383
2384 /* origin_head shouldn't be modified unless 'force' */
2385 if (!force &&
2386 dsl_dataset_modified_since_snap(origin_head, origin_head->ds_prev))
2387 return (SET_ERROR(ETXTBSY));
2388
2389 /* origin_head should have no long holds (e.g. is not mounted) */
2390 if (dsl_dataset_handoff_check(origin_head, owner, tx))
2391 return (SET_ERROR(EBUSY));
2392
2393 /* check amount of any unconsumed refreservation */
2394 unused_refres_delta =
2395 (int64_t)MIN(origin_head->ds_reserved,
2396 origin_head->ds_phys->ds_unique_bytes) -
2397 (int64_t)MIN(origin_head->ds_reserved,
2398 clone->ds_phys->ds_unique_bytes);
2399
2400 if (unused_refres_delta > 0 &&
2401 unused_refres_delta >
2402 dsl_dir_space_available(origin_head->ds_dir, NULL, 0, TRUE))
2403 return (SET_ERROR(ENOSPC));
2404
2405 /* clone can't be over the head's refquota */
2406 if (origin_head->ds_quota != 0 &&
2407 clone->ds_phys->ds_referenced_bytes > origin_head->ds_quota)
2408 return (SET_ERROR(EDQUOT));
2409
2410 return (0);
2411 }
2412
2413 void
2414 dsl_dataset_clone_swap_sync_impl(dsl_dataset_t *clone,
2415 dsl_dataset_t *origin_head, dmu_tx_t *tx)
2416 {
2417 dsl_pool_t *dp = dmu_tx_pool(tx);
2418 int64_t unused_refres_delta;
2419
2420 ASSERT(clone->ds_reserved == 0);
2421 ASSERT(origin_head->ds_quota == 0 ||
2422 clone->ds_phys->ds_unique_bytes <= origin_head->ds_quota);
2423 ASSERT3P(clone->ds_prev, ==, origin_head->ds_prev);
2424
2425 dmu_buf_will_dirty(clone->ds_dbuf, tx);
2426 dmu_buf_will_dirty(origin_head->ds_dbuf, tx);
2427
2428 if (clone->ds_objset != NULL) {
2429 dmu_objset_evict(clone->ds_objset);
2430 clone->ds_objset = NULL;
2431 }
2432
2433 if (origin_head->ds_objset != NULL) {
2434 dmu_objset_evict(origin_head->ds_objset);
2435 origin_head->ds_objset = NULL;
2436 }
2437
2438 unused_refres_delta =
2439 (int64_t)MIN(origin_head->ds_reserved,
2440 origin_head->ds_phys->ds_unique_bytes) -
2441 (int64_t)MIN(origin_head->ds_reserved,
2442 clone->ds_phys->ds_unique_bytes);
2443
2444 /*
2445 * Reset origin's unique bytes, if it exists.
2446 */
2447 if (clone->ds_prev) {
2448 dsl_dataset_t *origin = clone->ds_prev;
2449 uint64_t comp, uncomp;
2450
2451 dmu_buf_will_dirty(origin->ds_dbuf, tx);
2452 dsl_deadlist_space_range(&clone->ds_deadlist,
2453 origin->ds_phys->ds_prev_snap_txg, UINT64_MAX,
2454 &origin->ds_phys->ds_unique_bytes, &comp, &uncomp);
2455 }
2456
2457 /* swap blkptrs */
2458 {
2459 blkptr_t tmp;
2460 tmp = origin_head->ds_phys->ds_bp;
2461 origin_head->ds_phys->ds_bp = clone->ds_phys->ds_bp;
2462 clone->ds_phys->ds_bp = tmp;
2463 }
2464
2465 /* set dd_*_bytes */
2466 {
2467 int64_t dused, dcomp, duncomp;
2468 uint64_t cdl_used, cdl_comp, cdl_uncomp;
2469 uint64_t odl_used, odl_comp, odl_uncomp;
2470
2471 ASSERT3U(clone->ds_dir->dd_phys->
2472 dd_used_breakdown[DD_USED_SNAP], ==, 0);
2473
2474 dsl_deadlist_space(&clone->ds_deadlist,
2475 &cdl_used, &cdl_comp, &cdl_uncomp);
2476 dsl_deadlist_space(&origin_head->ds_deadlist,
2477 &odl_used, &odl_comp, &odl_uncomp);
2478
2479 dused = clone->ds_phys->ds_referenced_bytes + cdl_used -
2480 (origin_head->ds_phys->ds_referenced_bytes + odl_used);
2481 dcomp = clone->ds_phys->ds_compressed_bytes + cdl_comp -
2482 (origin_head->ds_phys->ds_compressed_bytes + odl_comp);
2483 duncomp = clone->ds_phys->ds_uncompressed_bytes +
2484 cdl_uncomp -
2485 (origin_head->ds_phys->ds_uncompressed_bytes + odl_uncomp);
2486
2487 dsl_dir_diduse_space(origin_head->ds_dir, DD_USED_HEAD,
2488 dused, dcomp, duncomp, tx);
2489 dsl_dir_diduse_space(clone->ds_dir, DD_USED_HEAD,
2490 -dused, -dcomp, -duncomp, tx);
2491
2492 /*
2493 * The difference in the space used by snapshots is the
2494 * difference in snapshot space due to the head's
2495 * deadlist (since that's the only thing that's
2496 * changing that affects the snapused).
2497 */
2498 dsl_deadlist_space_range(&clone->ds_deadlist,
2499 origin_head->ds_dir->dd_origin_txg, UINT64_MAX,
2500 &cdl_used, &cdl_comp, &cdl_uncomp);
2501 dsl_deadlist_space_range(&origin_head->ds_deadlist,
2502 origin_head->ds_dir->dd_origin_txg, UINT64_MAX,
2503 &odl_used, &odl_comp, &odl_uncomp);
2504 dsl_dir_transfer_space(origin_head->ds_dir, cdl_used - odl_used,
2505 DD_USED_HEAD, DD_USED_SNAP, tx);
2506 }
2507
2508 /* swap ds_*_bytes */
2509 SWITCH64(origin_head->ds_phys->ds_referenced_bytes,
2510 clone->ds_phys->ds_referenced_bytes);
2511 SWITCH64(origin_head->ds_phys->ds_compressed_bytes,
2512 clone->ds_phys->ds_compressed_bytes);
2513 SWITCH64(origin_head->ds_phys->ds_uncompressed_bytes,
2514 clone->ds_phys->ds_uncompressed_bytes);
2515 SWITCH64(origin_head->ds_phys->ds_unique_bytes,
2516 clone->ds_phys->ds_unique_bytes);
2517
2518 /* apply any parent delta for change in unconsumed refreservation */
2519 dsl_dir_diduse_space(origin_head->ds_dir, DD_USED_REFRSRV,
2520 unused_refres_delta, 0, 0, tx);
2521
2522 /*
2523 * Swap deadlists.
2524 */
2525 dsl_deadlist_close(&clone->ds_deadlist);
2526 dsl_deadlist_close(&origin_head->ds_deadlist);
2527 SWITCH64(origin_head->ds_phys->ds_deadlist_obj,
2528 clone->ds_phys->ds_deadlist_obj);
2529 dsl_deadlist_open(&clone->ds_deadlist, dp->dp_meta_objset,
2530 clone->ds_phys->ds_deadlist_obj);
2531 dsl_deadlist_open(&origin_head->ds_deadlist, dp->dp_meta_objset,
2532 origin_head->ds_phys->ds_deadlist_obj);
2533
2534 dsl_scan_ds_clone_swapped(origin_head, clone, tx);
2535
2536 spa_history_log_internal_ds(clone, "clone swap", tx,
2537 "parent=%s", origin_head->ds_dir->dd_myname);
2538 }
2539
2540 /*
2541 * Given a pool name and a dataset object number in that pool,
2542 * return the name of that dataset.
2543 */
2544 int
2545 dsl_dsobj_to_dsname(char *pname, uint64_t obj, char *buf)
2546 {
2547 dsl_pool_t *dp;
2548 dsl_dataset_t *ds;
2549 int error;
2550
2551 error = dsl_pool_hold(pname, FTAG, &dp);
2552 if (error != 0)
2553 return (error);
2554
2555 error = dsl_dataset_hold_obj(dp, obj, FTAG, &ds);
2556 if (error == 0) {
2557 dsl_dataset_name(ds, buf);
2558 dsl_dataset_rele(ds, FTAG);
2559 }
2560 dsl_pool_rele(dp, FTAG);
2561
2562 return (error);
2563 }
2564
2565 int
2566 dsl_dataset_check_quota(dsl_dataset_t *ds, boolean_t check_quota,
2567 uint64_t asize, uint64_t inflight, uint64_t *used, uint64_t *ref_rsrv)
2568 {
2569 int error = 0;
2570
2571 ASSERT3S(asize, >, 0);
2572
2573 /*
2574 * *ref_rsrv is the portion of asize that will come from any
2575 * unconsumed refreservation space.
2576 */
2577 *ref_rsrv = 0;
2578
2579 mutex_enter(&ds->ds_lock);
2580 /*
2581 * Make a space adjustment for reserved bytes.
2582 */
2583 if (ds->ds_reserved > ds->ds_phys->ds_unique_bytes) {
2584 ASSERT3U(*used, >=,
2585 ds->ds_reserved - ds->ds_phys->ds_unique_bytes);
2586 *used -= (ds->ds_reserved - ds->ds_phys->ds_unique_bytes);
2587 *ref_rsrv =
2588 asize - MIN(asize, parent_delta(ds, asize + inflight));
2589 }
2590
2591 if (!check_quota || ds->ds_quota == 0) {
2592 mutex_exit(&ds->ds_lock);
2593 return (0);
2594 }
2595 /*
2596 * If they are requesting more space, and our current estimate
2597 * is over quota, they get to try again unless the actual
2598 * on-disk is over quota and there are no pending changes (which
2599 * may free up space for us).
2600 */
2601 if (ds->ds_phys->ds_referenced_bytes + inflight >= ds->ds_quota) {
2602 if (inflight > 0 ||
2603 ds->ds_phys->ds_referenced_bytes < ds->ds_quota)
2604 error = SET_ERROR(ERESTART);
2605 else
2606 error = SET_ERROR(EDQUOT);
2607 }
2608 mutex_exit(&ds->ds_lock);
2609
2610 return (error);
2611 }
2612
2613 typedef struct dsl_dataset_set_qr_arg {
2614 const char *ddsqra_name;
2615 zprop_source_t ddsqra_source;
2616 uint64_t ddsqra_value;
2617 } dsl_dataset_set_qr_arg_t;
2618
2619
2620 /* ARGSUSED */
2621 static int
2622 dsl_dataset_set_refquota_check(void *arg, dmu_tx_t *tx)
2623 {
2624 dsl_dataset_set_qr_arg_t *ddsqra = arg;
2625 dsl_pool_t *dp = dmu_tx_pool(tx);
2626 dsl_dataset_t *ds;
2627 int error;
2628 uint64_t newval;
2629
2630 if (spa_version(dp->dp_spa) < SPA_VERSION_REFQUOTA)
2631 return (SET_ERROR(ENOTSUP));
2632
2633 error = dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds);
2634 if (error != 0)
2635 return (error);
2636
2637 if (dsl_dataset_is_snapshot(ds)) {
2638 dsl_dataset_rele(ds, FTAG);
2639 return (SET_ERROR(EINVAL));
2640 }
2641
2642 error = dsl_prop_predict(ds->ds_dir,
2643 zfs_prop_to_name(ZFS_PROP_REFQUOTA),
2644 ddsqra->ddsqra_source, ddsqra->ddsqra_value, &newval);
2645 if (error != 0) {
2646 dsl_dataset_rele(ds, FTAG);
2647 return (error);
2648 }
2649
2650 if (newval == 0) {
2651 dsl_dataset_rele(ds, FTAG);
2652 return (0);
2653 }
2654
2655 if (newval < ds->ds_phys->ds_referenced_bytes ||
2656 newval < ds->ds_reserved) {
2657 dsl_dataset_rele(ds, FTAG);
2658 return (SET_ERROR(ENOSPC));
2659 }
2660
2661 dsl_dataset_rele(ds, FTAG);
2662 return (0);
2663 }
2664
2665 static void
2666 dsl_dataset_set_refquota_sync(void *arg, dmu_tx_t *tx)
2667 {
2668 dsl_dataset_set_qr_arg_t *ddsqra = arg;
2669 dsl_pool_t *dp = dmu_tx_pool(tx);
2670 dsl_dataset_t *ds;
2671 uint64_t newval;
2672
2673 VERIFY0(dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds));
2674
2675 dsl_prop_set_sync_impl(ds,
2676 zfs_prop_to_name(ZFS_PROP_REFQUOTA),
2677 ddsqra->ddsqra_source, sizeof (ddsqra->ddsqra_value), 1,
2678 &ddsqra->ddsqra_value, tx);
2679
2680 VERIFY0(dsl_prop_get_int_ds(ds,
2681 zfs_prop_to_name(ZFS_PROP_REFQUOTA), &newval));
2682
2683 if (ds->ds_quota != newval) {
2684 dmu_buf_will_dirty(ds->ds_dbuf, tx);
2685 ds->ds_quota = newval;
2686 }
2687 dsl_dataset_rele(ds, FTAG);
2688 }
2689
2690 int
2691 dsl_dataset_set_refquota(const char *dsname, zprop_source_t source,
2692 uint64_t refquota)
2693 {
2694 dsl_dataset_set_qr_arg_t ddsqra;
2695
2696 ddsqra.ddsqra_name = dsname;
2697 ddsqra.ddsqra_source = source;
2698 ddsqra.ddsqra_value = refquota;
2699
2700 return (dsl_sync_task(dsname, dsl_dataset_set_refquota_check,
2701 dsl_dataset_set_refquota_sync, &ddsqra, 0));
2702 }
2703
2704 static int
2705 dsl_dataset_set_refreservation_check(void *arg, dmu_tx_t *tx)
2706 {
2707 dsl_dataset_set_qr_arg_t *ddsqra = arg;
2708 dsl_pool_t *dp = dmu_tx_pool(tx);
2709 dsl_dataset_t *ds;
2710 int error;
2711 uint64_t newval, unique;
2712
2713 if (spa_version(dp->dp_spa) < SPA_VERSION_REFRESERVATION)
2714 return (SET_ERROR(ENOTSUP));
2715
2716 error = dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds);
2717 if (error != 0)
2718 return (error);
2719
2720 if (dsl_dataset_is_snapshot(ds)) {
2721 dsl_dataset_rele(ds, FTAG);
2722 return (SET_ERROR(EINVAL));
2723 }
2724
2725 error = dsl_prop_predict(ds->ds_dir,
2726 zfs_prop_to_name(ZFS_PROP_REFRESERVATION),
2727 ddsqra->ddsqra_source, ddsqra->ddsqra_value, &newval);
2728 if (error != 0) {
2729 dsl_dataset_rele(ds, FTAG);
2730 return (error);
2731 }
2732
2733 /*
2734 * If we are doing the preliminary check in open context, the
2735 * space estimates may be inaccurate.
2736 */
2737 if (!dmu_tx_is_syncing(tx)) {
2738 dsl_dataset_rele(ds, FTAG);
2739 return (0);
2740 }
2741
2742 mutex_enter(&ds->ds_lock);
2743 if (!DS_UNIQUE_IS_ACCURATE(ds))
2744 dsl_dataset_recalc_head_uniq(ds);
2745 unique = ds->ds_phys->ds_unique_bytes;
2746 mutex_exit(&ds->ds_lock);
2747
2748 if (MAX(unique, newval) > MAX(unique, ds->ds_reserved)) {
2749 uint64_t delta = MAX(unique, newval) -
2750 MAX(unique, ds->ds_reserved);
2751
2752 if (delta >
2753 dsl_dir_space_available(ds->ds_dir, NULL, 0, B_TRUE) ||
2754 (ds->ds_quota > 0 && newval > ds->ds_quota)) {
2755 dsl_dataset_rele(ds, FTAG);
2756 return (SET_ERROR(ENOSPC));
2757 }
2758 }
2759
2760 dsl_dataset_rele(ds, FTAG);
2761 return (0);
2762 }
2763
2764 void
2765 dsl_dataset_set_refreservation_sync_impl(dsl_dataset_t *ds,
2766 zprop_source_t source, uint64_t value, dmu_tx_t *tx)
2767 {
2768 uint64_t newval;
2769 uint64_t unique;
2770 int64_t delta;
2771
2772 dsl_prop_set_sync_impl(ds, zfs_prop_to_name(ZFS_PROP_REFRESERVATION),
2773 source, sizeof (value), 1, &value, tx);
2774
2775 VERIFY0(dsl_prop_get_int_ds(ds,
2776 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), &newval));
2777
2778 dmu_buf_will_dirty(ds->ds_dbuf, tx);
2779 mutex_enter(&ds->ds_dir->dd_lock);
2780 mutex_enter(&ds->ds_lock);
2781 ASSERT(DS_UNIQUE_IS_ACCURATE(ds));
2782 unique = ds->ds_phys->ds_unique_bytes;
2783 delta = MAX(0, (int64_t)(newval - unique)) -
2784 MAX(0, (int64_t)(ds->ds_reserved - unique));
2785 ds->ds_reserved = newval;
2786 mutex_exit(&ds->ds_lock);
2787
2788 dsl_dir_diduse_space(ds->ds_dir, DD_USED_REFRSRV, delta, 0, 0, tx);
2789 mutex_exit(&ds->ds_dir->dd_lock);
2790 }
2791
2792 static void
2793 dsl_dataset_set_refreservation_sync(void *arg, dmu_tx_t *tx)
2794 {
2795 dsl_dataset_set_qr_arg_t *ddsqra = arg;
2796 dsl_pool_t *dp = dmu_tx_pool(tx);
2797 dsl_dataset_t *ds;
2798
2799 VERIFY0(dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds));
2800 dsl_dataset_set_refreservation_sync_impl(ds,
2801 ddsqra->ddsqra_source, ddsqra->ddsqra_value, tx);
2802 dsl_dataset_rele(ds, FTAG);
2803 }
2804
2805 int
2806 dsl_dataset_set_refreservation(const char *dsname, zprop_source_t source,
2807 uint64_t refreservation)
2808 {
2809 dsl_dataset_set_qr_arg_t ddsqra;
2810
2811 ddsqra.ddsqra_name = dsname;
2812 ddsqra.ddsqra_source = source;
2813 ddsqra.ddsqra_value = refreservation;
2814
2815 return (dsl_sync_task(dsname, dsl_dataset_set_refreservation_check,
2816 dsl_dataset_set_refreservation_sync, &ddsqra, 0));
2817 }
2818
2819 /*
2820 * Return (in *usedp) the amount of space written in new that is not
2821 * present in oldsnap. New may be a snapshot or the head. Old must be
2822 * a snapshot before new, in new's filesystem (or its origin). If not then
2823 * fail and return EINVAL.
2824 *
2825 * The written space is calculated by considering two components: First, we
2826 * ignore any freed space, and calculate the written as new's used space
2827 * minus old's used space. Next, we add in the amount of space that was freed
2828 * between the two snapshots, thus reducing new's used space relative to old's.
2829 * Specifically, this is the space that was born before old->ds_creation_txg,
2830 * and freed before new (ie. on new's deadlist or a previous deadlist).
2831 *
2832 * space freed [---------------------]
2833 * snapshots ---O-------O--------O-------O------
2834 * oldsnap new
2835 */
2836 int
2837 dsl_dataset_space_written(dsl_dataset_t *oldsnap, dsl_dataset_t *new,
2838 uint64_t *usedp, uint64_t *compp, uint64_t *uncompp)
2839 {
2840 int err = 0;
2841 uint64_t snapobj;
2842 dsl_pool_t *dp = new->ds_dir->dd_pool;
2843
2844 ASSERT(dsl_pool_config_held(dp));
2845
2846 *usedp = 0;
2847 *usedp += new->ds_phys->ds_referenced_bytes;
2848 *usedp -= oldsnap->ds_phys->ds_referenced_bytes;
2849
2850 *compp = 0;
2851 *compp += new->ds_phys->ds_compressed_bytes;
2852 *compp -= oldsnap->ds_phys->ds_compressed_bytes;
2853
2854 *uncompp = 0;
2855 *uncompp += new->ds_phys->ds_uncompressed_bytes;
2856 *uncompp -= oldsnap->ds_phys->ds_uncompressed_bytes;
2857
2858 snapobj = new->ds_object;
2859 while (snapobj != oldsnap->ds_object) {
2860 dsl_dataset_t *snap;
2861 uint64_t used, comp, uncomp;
2862
2863 if (snapobj == new->ds_object) {
2864 snap = new;
2865 } else {
2866 err = dsl_dataset_hold_obj(dp, snapobj, FTAG, &snap);
2867 if (err != 0)
2868 break;
2869 }
2870
2871 if (snap->ds_phys->ds_prev_snap_txg ==
2872 oldsnap->ds_phys->ds_creation_txg) {
2873 /*
2874 * The blocks in the deadlist can not be born after
2875 * ds_prev_snap_txg, so get the whole deadlist space,
2876 * which is more efficient (especially for old-format
2877 * deadlists). Unfortunately the deadlist code
2878 * doesn't have enough information to make this
2879 * optimization itself.
2880 */
2881 dsl_deadlist_space(&snap->ds_deadlist,
2882 &used, &comp, &uncomp);
2883 } else {
2884 dsl_deadlist_space_range(&snap->ds_deadlist,
2885 0, oldsnap->ds_phys->ds_creation_txg,
2886 &used, &comp, &uncomp);
2887 }
2888 *usedp += used;
2889 *compp += comp;
2890 *uncompp += uncomp;
2891
2892 /*
2893 * If we get to the beginning of the chain of snapshots
2894 * (ds_prev_snap_obj == 0) before oldsnap, then oldsnap
2895 * was not a snapshot of/before new.
2896 */
2897 snapobj = snap->ds_phys->ds_prev_snap_obj;
2898 if (snap != new)
2899 dsl_dataset_rele(snap, FTAG);
2900 if (snapobj == 0) {
2901 err = SET_ERROR(EINVAL);
2902 break;
2903 }
2904
2905 }
2906 return (err);
2907 }
2908
2909 /*
2910 * Return (in *usedp) the amount of space that will be reclaimed if firstsnap,
2911 * lastsnap, and all snapshots in between are deleted.
2912 *
2913 * blocks that would be freed [---------------------------]
2914 * snapshots ---O-------O--------O-------O--------O
2915 * firstsnap lastsnap
2916 *
2917 * This is the set of blocks that were born after the snap before firstsnap,
2918 * (birth > firstsnap->prev_snap_txg) and died before the snap after the
2919 * last snap (ie, is on lastsnap->ds_next->ds_deadlist or an earlier deadlist).
2920 * We calculate this by iterating over the relevant deadlists (from the snap
2921 * after lastsnap, backward to the snap after firstsnap), summing up the
2922 * space on the deadlist that was born after the snap before firstsnap.
2923 */
2924 int
2925 dsl_dataset_space_wouldfree(dsl_dataset_t *firstsnap,
2926 dsl_dataset_t *lastsnap,
2927 uint64_t *usedp, uint64_t *compp, uint64_t *uncompp)
2928 {
2929 int err = 0;
2930 uint64_t snapobj;
2931 dsl_pool_t *dp = firstsnap->ds_dir->dd_pool;
2932
2933 ASSERT(dsl_dataset_is_snapshot(firstsnap));
2934 ASSERT(dsl_dataset_is_snapshot(lastsnap));
2935
2936 /*
2937 * Check that the snapshots are in the same dsl_dir, and firstsnap
2938 * is before lastsnap.
2939 */
2940 if (firstsnap->ds_dir != lastsnap->ds_dir ||
2941 firstsnap->ds_phys->ds_creation_txg >
2942 lastsnap->ds_phys->ds_creation_txg)
2943 return (SET_ERROR(EINVAL));
2944
2945 *usedp = *compp = *uncompp = 0;
2946
2947 snapobj = lastsnap->ds_phys->ds_next_snap_obj;
2948 while (snapobj != firstsnap->ds_object) {
2949 dsl_dataset_t *ds;
2950 uint64_t used, comp, uncomp;
2951
2952 err = dsl_dataset_hold_obj(dp, snapobj, FTAG, &ds);
2953 if (err != 0)
2954 break;
2955
2956 dsl_deadlist_space_range(&ds->ds_deadlist,
2957 firstsnap->ds_phys->ds_prev_snap_txg, UINT64_MAX,
2958 &used, &comp, &uncomp);
2959 *usedp += used;
2960 *compp += comp;
2961 *uncompp += uncomp;
2962
2963 snapobj = ds->ds_phys->ds_prev_snap_obj;
2964 ASSERT3U(snapobj, !=, 0);
2965 dsl_dataset_rele(ds, FTAG);
2966 }
2967 return (err);
2968 }
2969
2970 /*
2971 * Return TRUE if 'earlier' is an earlier snapshot in 'later's timeline.
2972 * For example, they could both be snapshots of the same filesystem, and
2973 * 'earlier' is before 'later'. Or 'earlier' could be the origin of
2974 * 'later's filesystem. Or 'earlier' could be an older snapshot in the origin's
2975 * filesystem. Or 'earlier' could be the origin's origin.
2976 *
2977 * If non-zero, earlier_txg is used instead of earlier's ds_creation_txg.
2978 */
2979 boolean_t
2980 dsl_dataset_is_before(dsl_dataset_t *later, dsl_dataset_t *earlier,
2981 uint64_t earlier_txg)
2982 {
2983 dsl_pool_t *dp = later->ds_dir->dd_pool;
2984 int error;
2985 boolean_t ret;
2986
2987 ASSERT(dsl_pool_config_held(dp));
2988 ASSERT(dsl_dataset_is_snapshot(earlier) || earlier_txg != 0);
2989
2990 if (earlier_txg == 0)
2991 earlier_txg = earlier->ds_phys->ds_creation_txg;
2992
2993 if (dsl_dataset_is_snapshot(later) &&
2994 earlier_txg >= later->ds_phys->ds_creation_txg)
2995 return (B_FALSE);
2996
2997 if (later->ds_dir == earlier->ds_dir)
2998 return (B_TRUE);
2999 if (!dsl_dir_is_clone(later->ds_dir))
3000 return (B_FALSE);
3001
3002 if (later->ds_dir->dd_phys->dd_origin_obj == earlier->ds_object)
3003 return (B_TRUE);
3004 dsl_dataset_t *origin;
3005 error = dsl_dataset_hold_obj(dp,
3006 later->ds_dir->dd_phys->dd_origin_obj, FTAG, &origin);
3007 if (error != 0)
3008 return (B_FALSE);
3009 ret = dsl_dataset_is_before(origin, earlier, earlier_txg);
3010 dsl_dataset_rele(origin, FTAG);
3011 return (ret);
3012 }
3013
3014
3015 void
3016 dsl_dataset_zapify(dsl_dataset_t *ds, dmu_tx_t *tx)
3017 {
3018 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
3019 dmu_object_zapify(mos, ds->ds_object, DMU_OT_DSL_DATASET, tx);
3020 }