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