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 * Copyright (c) 2014 RackTop Systems.
26 */
27
28 #include <sys/dmu_objset.h>
29 #include <sys/dsl_dataset.h>
30 #include <sys/dsl_dir.h>
31 #include <sys/dsl_prop.h>
32 #include <sys/dsl_synctask.h>
33 #include <sys/dmu_traverse.h>
34 #include <sys/dmu_impl.h>
35 #include <sys/dmu_tx.h>
36 #include <sys/arc.h>
37 #include <sys/zio.h>
38 #include <sys/zap.h>
39 #include <sys/zfeature.h>
40 #include <sys/unique.h>
41 #include <sys/zfs_context.h>
42 #include <sys/zfs_ioctl.h>
43 #include <sys/spa.h>
44 #include <sys/zfs_znode.h>
45 #include <sys/zfs_onexit.h>
46 #include <sys/zvol.h>
47 #include <sys/dsl_scan.h>
48 #include <sys/dsl_deadlist.h>
49 #include <sys/dsl_destroy.h>
50 #include <sys/dsl_userhold.h>
51 #include <sys/dsl_bookmark.h>
52
53 #define SWITCH64(x, y) \
54 { \
55 uint64_t __tmp = (x); \
56 (x) = (y); \
57 (y) = __tmp; \
58 }
59
60 #define DS_REF_MAX (1ULL << 62)
61
62 #define DSL_DEADLIST_BLOCKSIZE SPA_MAXBLOCKSIZE
63
64 /*
65 * Figure out how much of this delta should be propogated to the dsl_dir
66 * layer. If there's a refreservation, that space has already been
67 * partially accounted for in our ancestors.
68 */
69 static int64_t
70 parent_delta(dsl_dataset_t *ds, int64_t delta)
71 {
72 uint64_t old_bytes, new_bytes;
73
74 if (ds->ds_reserved == 0)
75 return (delta);
76
77 old_bytes = MAX(ds->ds_phys->ds_unique_bytes, ds->ds_reserved);
78 new_bytes = MAX(ds->ds_phys->ds_unique_bytes + delta, ds->ds_reserved);
79
80 ASSERT3U(ABS((int64_t)(new_bytes - old_bytes)), <=, ABS(delta));
81 return (new_bytes - old_bytes);
82 }
83
84 void
85 dsl_dataset_block_born(dsl_dataset_t *ds, const blkptr_t *bp, dmu_tx_t *tx)
86 {
87 int used = bp_get_dsize_sync(tx->tx_pool->dp_spa, bp);
88 int compressed = BP_GET_PSIZE(bp);
89 int uncompressed = BP_GET_UCSIZE(bp);
90 int64_t delta;
91
92 dprintf_bp(bp, "ds=%p", ds);
93
94 ASSERT(dmu_tx_is_syncing(tx));
95 /* It could have been compressed away to nothing */
96 if (BP_IS_HOLE(bp))
97 return;
98 ASSERT(BP_GET_TYPE(bp) != DMU_OT_NONE);
99 ASSERT(DMU_OT_IS_VALID(BP_GET_TYPE(bp)));
100 if (ds == NULL) {
101 dsl_pool_mos_diduse_space(tx->tx_pool,
102 used, compressed, uncompressed);
103 return;
104 }
105
106 dmu_buf_will_dirty(ds->ds_dbuf, tx);
107 mutex_enter(&ds->ds_lock);
108 delta = parent_delta(ds, used);
109 ds->ds_phys->ds_referenced_bytes += used;
110 ds->ds_phys->ds_compressed_bytes += compressed;
111 ds->ds_phys->ds_uncompressed_bytes += uncompressed;
112 ds->ds_phys->ds_unique_bytes += used;
113 mutex_exit(&ds->ds_lock);
114 dsl_dir_diduse_space(ds->ds_dir, DD_USED_HEAD, delta,
115 compressed, uncompressed, tx);
116 dsl_dir_transfer_space(ds->ds_dir, used - delta,
117 DD_USED_REFRSRV, DD_USED_HEAD, tx);
118 }
119
120 int
121 dsl_dataset_block_kill(dsl_dataset_t *ds, const blkptr_t *bp, dmu_tx_t *tx,
122 boolean_t async)
123 {
124 int used = bp_get_dsize_sync(tx->tx_pool->dp_spa, bp);
125 int compressed = BP_GET_PSIZE(bp);
126 int uncompressed = BP_GET_UCSIZE(bp);
127
128 if (BP_IS_HOLE(bp))
129 return (0);
130
131 ASSERT(dmu_tx_is_syncing(tx));
132 ASSERT(bp->blk_birth <= tx->tx_txg);
133
134 if (ds == NULL) {
135 dsl_free(tx->tx_pool, tx->tx_txg, bp);
136 dsl_pool_mos_diduse_space(tx->tx_pool,
137 -used, -compressed, -uncompressed);
138 return (used);
139 }
140 ASSERT3P(tx->tx_pool, ==, ds->ds_dir->dd_pool);
141
142 ASSERT(!dsl_dataset_is_snapshot(ds));
143 dmu_buf_will_dirty(ds->ds_dbuf, tx);
144
145 if (bp->blk_birth > ds->ds_phys->ds_prev_snap_txg) {
146 int64_t delta;
147
148 dprintf_bp(bp, "freeing ds=%llu", ds->ds_object);
149 dsl_free(tx->tx_pool, tx->tx_txg, bp);
150
151 mutex_enter(&ds->ds_lock);
152 ASSERT(ds->ds_phys->ds_unique_bytes >= used ||
153 !DS_UNIQUE_IS_ACCURATE(ds));
154 delta = parent_delta(ds, -used);
155 ds->ds_phys->ds_unique_bytes -= used;
156 mutex_exit(&ds->ds_lock);
157 dsl_dir_diduse_space(ds->ds_dir, DD_USED_HEAD,
158 delta, -compressed, -uncompressed, tx);
159 dsl_dir_transfer_space(ds->ds_dir, -used - delta,
160 DD_USED_REFRSRV, DD_USED_HEAD, tx);
161 } else {
162 dprintf_bp(bp, "putting on dead list: %s", "");
163 if (async) {
164 /*
165 * We are here as part of zio's write done callback,
166 * which means we're a zio interrupt thread. We can't
167 * call dsl_deadlist_insert() now because it may block
168 * waiting for I/O. Instead, put bp on the deferred
169 * queue and let dsl_pool_sync() finish the job.
170 */
171 bplist_append(&ds->ds_pending_deadlist, bp);
172 } else {
173 dsl_deadlist_insert(&ds->ds_deadlist, bp, tx);
174 }
175 ASSERT3U(ds->ds_prev->ds_object, ==,
176 ds->ds_phys->ds_prev_snap_obj);
177 ASSERT(ds->ds_prev->ds_phys->ds_num_children > 0);
178 /* if (bp->blk_birth > prev prev snap txg) prev unique += bs */
179 if (ds->ds_prev->ds_phys->ds_next_snap_obj ==
180 ds->ds_object && bp->blk_birth >
181 ds->ds_prev->ds_phys->ds_prev_snap_txg) {
182 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx);
183 mutex_enter(&ds->ds_prev->ds_lock);
184 ds->ds_prev->ds_phys->ds_unique_bytes += used;
185 mutex_exit(&ds->ds_prev->ds_lock);
186 }
187 if (bp->blk_birth > ds->ds_dir->dd_origin_txg) {
188 dsl_dir_transfer_space(ds->ds_dir, used,
189 DD_USED_HEAD, DD_USED_SNAP, tx);
190 }
191 }
192 mutex_enter(&ds->ds_lock);
193 ASSERT3U(ds->ds_phys->ds_referenced_bytes, >=, used);
194 ds->ds_phys->ds_referenced_bytes -= used;
195 ASSERT3U(ds->ds_phys->ds_compressed_bytes, >=, compressed);
196 ds->ds_phys->ds_compressed_bytes -= compressed;
197 ASSERT3U(ds->ds_phys->ds_uncompressed_bytes, >=, uncompressed);
198 ds->ds_phys->ds_uncompressed_bytes -= uncompressed;
199 mutex_exit(&ds->ds_lock);
200
201 return (used);
202 }
203
204 uint64_t
205 dsl_dataset_prev_snap_txg(dsl_dataset_t *ds)
206 {
207 uint64_t trysnap = 0;
208
209 if (ds == NULL)
210 return (0);
211 /*
212 * The snapshot creation could fail, but that would cause an
213 * incorrect FALSE return, which would only result in an
214 * overestimation of the amount of space that an operation would
215 * consume, which is OK.
216 *
217 * There's also a small window where we could miss a pending
218 * snapshot, because we could set the sync task in the quiescing
219 * phase. So this should only be used as a guess.
220 */
221 if (ds->ds_trysnap_txg >
222 spa_last_synced_txg(ds->ds_dir->dd_pool->dp_spa))
223 trysnap = ds->ds_trysnap_txg;
224 return (MAX(ds->ds_phys->ds_prev_snap_txg, trysnap));
225 }
226
227 boolean_t
228 dsl_dataset_block_freeable(dsl_dataset_t *ds, const blkptr_t *bp,
229 uint64_t blk_birth)
230 {
231 if (blk_birth <= dsl_dataset_prev_snap_txg(ds) ||
232 (bp != NULL && BP_IS_HOLE(bp)))
233 return (B_FALSE);
234
235 ddt_prefetch(dsl_dataset_get_spa(ds), bp);
236
237 return (B_TRUE);
238 }
239
240 /* ARGSUSED */
241 static void
242 dsl_dataset_evict(dmu_buf_t *db, void *dsv)
243 {
244 dsl_dataset_t *ds = dsv;
245
246 ASSERT(ds->ds_owner == NULL);
247
248 unique_remove(ds->ds_fsid_guid);
249
250 if (ds->ds_objset != NULL)
251 dmu_objset_evict(ds->ds_objset);
252
253 if (ds->ds_prev) {
254 dsl_dataset_rele(ds->ds_prev, ds);
255 ds->ds_prev = NULL;
256 }
257
258 bplist_destroy(&ds->ds_pending_deadlist);
259 if (ds->ds_phys->ds_deadlist_obj != 0)
260 dsl_deadlist_close(&ds->ds_deadlist);
261 if (ds->ds_dir)
262 dsl_dir_rele(ds->ds_dir, ds);
263
264 ASSERT(!list_link_active(&ds->ds_synced_link));
265
266 mutex_destroy(&ds->ds_lock);
267 mutex_destroy(&ds->ds_opening_lock);
268 refcount_destroy(&ds->ds_longholds);
269
270 kmem_free(ds, sizeof (dsl_dataset_t));
271 }
272
273 int
274 dsl_dataset_get_snapname(dsl_dataset_t *ds)
275 {
276 dsl_dataset_phys_t *headphys;
277 int err;
278 dmu_buf_t *headdbuf;
279 dsl_pool_t *dp = ds->ds_dir->dd_pool;
280 objset_t *mos = dp->dp_meta_objset;
281
282 if (ds->ds_snapname[0])
283 return (0);
284 if (ds->ds_phys->ds_next_snap_obj == 0)
285 return (0);
286
287 err = dmu_bonus_hold(mos, ds->ds_dir->dd_phys->dd_head_dataset_obj,
288 FTAG, &headdbuf);
289 if (err != 0)
290 return (err);
291 headphys = headdbuf->db_data;
292 err = zap_value_search(dp->dp_meta_objset,
293 headphys->ds_snapnames_zapobj, ds->ds_object, 0, ds->ds_snapname);
294 dmu_buf_rele(headdbuf, FTAG);
295 return (err);
296 }
297
298 int
299 dsl_dataset_snap_lookup(dsl_dataset_t *ds, const char *name, uint64_t *value)
300 {
301 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
302 uint64_t snapobj = ds->ds_phys->ds_snapnames_zapobj;
303 matchtype_t mt;
304 int err;
305
306 if (ds->ds_phys->ds_flags & DS_FLAG_CI_DATASET)
307 mt = MT_FIRST;
308 else
309 mt = MT_EXACT;
310
311 err = zap_lookup_norm(mos, snapobj, name, 8, 1,
312 value, mt, NULL, 0, NULL);
313 if (err == ENOTSUP && mt == MT_FIRST)
314 err = zap_lookup(mos, snapobj, name, 8, 1, value);
315 return (err);
316 }
317
318 int
319 dsl_dataset_snap_remove(dsl_dataset_t *ds, const char *name, dmu_tx_t *tx)
320 {
321 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
322 uint64_t snapobj = ds->ds_phys->ds_snapnames_zapobj;
323 matchtype_t mt;
324 int err;
325
326 dsl_dir_snap_cmtime_update(ds->ds_dir);
327
328 if (ds->ds_phys->ds_flags & DS_FLAG_CI_DATASET)
329 mt = MT_FIRST;
330 else
331 mt = MT_EXACT;
332
333 err = zap_remove_norm(mos, snapobj, name, mt, tx);
334 if (err == ENOTSUP && mt == MT_FIRST)
335 err = zap_remove(mos, snapobj, name, tx);
336 return (err);
337 }
338
339 int
340 dsl_dataset_hold_obj(dsl_pool_t *dp, uint64_t dsobj, void *tag,
341 dsl_dataset_t **dsp)
342 {
343 objset_t *mos = dp->dp_meta_objset;
344 dmu_buf_t *dbuf;
345 dsl_dataset_t *ds;
346 int err;
347 dmu_object_info_t doi;
348
349 ASSERT(dsl_pool_config_held(dp));
350
351 err = dmu_bonus_hold(mos, dsobj, tag, &dbuf);
352 if (err != 0)
353 return (err);
354
355 /* Make sure dsobj has the correct object type. */
356 dmu_object_info_from_db(dbuf, &doi);
357 if (doi.doi_bonus_type != DMU_OT_DSL_DATASET) {
358 dmu_buf_rele(dbuf, tag);
359 return (SET_ERROR(EINVAL));
360 }
361
362 ds = dmu_buf_get_user(dbuf);
363 if (ds == NULL) {
364 dsl_dataset_t *winner = NULL;
365
366 ds = kmem_zalloc(sizeof (dsl_dataset_t), KM_SLEEP);
367 ds->ds_dbuf = dbuf;
368 ds->ds_object = dsobj;
369 ds->ds_phys = dbuf->db_data;
370
371 mutex_init(&ds->ds_lock, NULL, MUTEX_DEFAULT, NULL);
372 mutex_init(&ds->ds_opening_lock, NULL, MUTEX_DEFAULT, NULL);
373 mutex_init(&ds->ds_sendstream_lock, NULL, MUTEX_DEFAULT, NULL);
374 refcount_create(&ds->ds_longholds);
375
376 bplist_create(&ds->ds_pending_deadlist);
377 dsl_deadlist_open(&ds->ds_deadlist,
378 mos, ds->ds_phys->ds_deadlist_obj);
379
380 list_create(&ds->ds_sendstreams, sizeof (dmu_sendarg_t),
381 offsetof(dmu_sendarg_t, dsa_link));
382
383 if (err == 0) {
384 err = dsl_dir_hold_obj(dp,
385 ds->ds_phys->ds_dir_obj, NULL, ds, &ds->ds_dir);
386 }
387 if (err != 0) {
388 mutex_destroy(&ds->ds_lock);
389 mutex_destroy(&ds->ds_opening_lock);
390 refcount_destroy(&ds->ds_longholds);
391 bplist_destroy(&ds->ds_pending_deadlist);
392 dsl_deadlist_close(&ds->ds_deadlist);
393 kmem_free(ds, sizeof (dsl_dataset_t));
394 dmu_buf_rele(dbuf, tag);
395 return (err);
396 }
397
398 if (!dsl_dataset_is_snapshot(ds)) {
399 ds->ds_snapname[0] = '\0';
400 if (ds->ds_phys->ds_prev_snap_obj != 0) {
401 err = dsl_dataset_hold_obj(dp,
402 ds->ds_phys->ds_prev_snap_obj,
403 ds, &ds->ds_prev);
404 }
405 if (doi.doi_type == DMU_OTN_ZAP_METADATA) {
406 int zaperr = zap_lookup(mos, ds->ds_object,
407 DS_FIELD_BOOKMARK_NAMES,
408 sizeof (ds->ds_bookmarks), 1,
409 &ds->ds_bookmarks);
410 if (zaperr != ENOENT)
411 VERIFY0(zaperr);
412 }
413 } else {
414 if (zfs_flags & ZFS_DEBUG_SNAPNAMES)
415 err = dsl_dataset_get_snapname(ds);
416 if (err == 0 && ds->ds_phys->ds_userrefs_obj != 0) {
417 err = zap_count(
418 ds->ds_dir->dd_pool->dp_meta_objset,
419 ds->ds_phys->ds_userrefs_obj,
420 &ds->ds_userrefs);
421 }
422 }
423
424 if (err == 0 && !dsl_dataset_is_snapshot(ds)) {
425 err = dsl_prop_get_int_ds(ds,
426 zfs_prop_to_name(ZFS_PROP_REFRESERVATION),
427 &ds->ds_reserved);
428 if (err == 0) {
429 err = dsl_prop_get_int_ds(ds,
430 zfs_prop_to_name(ZFS_PROP_REFQUOTA),
431 &ds->ds_quota);
432 }
433 } else {
434 ds->ds_reserved = ds->ds_quota = 0;
435 }
436
437 if (err != 0 || (winner = dmu_buf_set_user_ie(dbuf, ds,
438 &ds->ds_phys, dsl_dataset_evict)) != NULL) {
439 bplist_destroy(&ds->ds_pending_deadlist);
440 dsl_deadlist_close(&ds->ds_deadlist);
441 if (ds->ds_prev)
442 dsl_dataset_rele(ds->ds_prev, ds);
443 dsl_dir_rele(ds->ds_dir, ds);
444 mutex_destroy(&ds->ds_lock);
445 mutex_destroy(&ds->ds_opening_lock);
446 refcount_destroy(&ds->ds_longholds);
447 kmem_free(ds, sizeof (dsl_dataset_t));
448 if (err != 0) {
449 dmu_buf_rele(dbuf, tag);
450 return (err);
451 }
452 ds = winner;
453 } else {
454 ds->ds_fsid_guid =
455 unique_insert(ds->ds_phys->ds_fsid_guid);
456 }
457 }
458 ASSERT3P(ds->ds_dbuf, ==, dbuf);
459 ASSERT3P(ds->ds_phys, ==, dbuf->db_data);
460 ASSERT(ds->ds_phys->ds_prev_snap_obj != 0 ||
461 spa_version(dp->dp_spa) < SPA_VERSION_ORIGIN ||
462 dp->dp_origin_snap == NULL || ds == dp->dp_origin_snap);
463 *dsp = ds;
464 return (0);
465 }
466
467 int
468 dsl_dataset_hold(dsl_pool_t *dp, const char *name,
469 void *tag, dsl_dataset_t **dsp)
470 {
471 dsl_dir_t *dd;
472 const char *snapname;
473 uint64_t obj;
474 int err = 0;
475
476 err = dsl_dir_hold(dp, name, FTAG, &dd, &snapname);
477 if (err != 0)
478 return (err);
479
480 ASSERT(dsl_pool_config_held(dp));
481 obj = dd->dd_phys->dd_head_dataset_obj;
482 if (obj != 0)
483 err = dsl_dataset_hold_obj(dp, obj, tag, dsp);
484 else
485 err = SET_ERROR(ENOENT);
486
487 /* we may be looking for a snapshot */
488 if (err == 0 && snapname != NULL) {
489 dsl_dataset_t *ds;
490
491 if (*snapname++ != '@') {
492 dsl_dataset_rele(*dsp, tag);
493 dsl_dir_rele(dd, FTAG);
494 return (SET_ERROR(ENOENT));
495 }
496
497 dprintf("looking for snapshot '%s'\n", snapname);
498 err = dsl_dataset_snap_lookup(*dsp, snapname, &obj);
499 if (err == 0)
500 err = dsl_dataset_hold_obj(dp, obj, tag, &ds);
501 dsl_dataset_rele(*dsp, tag);
502
503 if (err == 0) {
504 mutex_enter(&ds->ds_lock);
505 if (ds->ds_snapname[0] == 0)
506 (void) strlcpy(ds->ds_snapname, snapname,
507 sizeof (ds->ds_snapname));
508 mutex_exit(&ds->ds_lock);
509 *dsp = ds;
510 }
511 }
512
513 dsl_dir_rele(dd, FTAG);
514 return (err);
515 }
516
517 int
518 dsl_dataset_own_obj(dsl_pool_t *dp, uint64_t dsobj,
519 void *tag, dsl_dataset_t **dsp)
520 {
521 int err = dsl_dataset_hold_obj(dp, dsobj, tag, dsp);
522 if (err != 0)
523 return (err);
524 if (!dsl_dataset_tryown(*dsp, tag)) {
525 dsl_dataset_rele(*dsp, tag);
526 *dsp = NULL;
527 return (SET_ERROR(EBUSY));
528 }
529 return (0);
530 }
531
532 int
533 dsl_dataset_own(dsl_pool_t *dp, const char *name,
534 void *tag, dsl_dataset_t **dsp)
535 {
536 int err = dsl_dataset_hold(dp, name, tag, dsp);
537 if (err != 0)
538 return (err);
539 if (!dsl_dataset_tryown(*dsp, tag)) {
540 dsl_dataset_rele(*dsp, tag);
541 return (SET_ERROR(EBUSY));
542 }
543 return (0);
544 }
545
546 /*
547 * See the comment above dsl_pool_hold() for details. In summary, a long
548 * hold is used to prevent destruction of a dataset while the pool hold
549 * is dropped, allowing other concurrent operations (e.g. spa_sync()).
550 *
551 * The dataset and pool must be held when this function is called. After it
552 * is called, the pool hold may be released while the dataset is still held
553 * and accessed.
554 */
555 void
556 dsl_dataset_long_hold(dsl_dataset_t *ds, void *tag)
557 {
558 ASSERT(dsl_pool_config_held(ds->ds_dir->dd_pool));
559 (void) refcount_add(&ds->ds_longholds, tag);
560 }
561
562 void
563 dsl_dataset_long_rele(dsl_dataset_t *ds, void *tag)
564 {
565 (void) refcount_remove(&ds->ds_longholds, tag);
566 }
567
568 /* Return B_TRUE if there are any long holds on this dataset. */
569 boolean_t
570 dsl_dataset_long_held(dsl_dataset_t *ds)
571 {
572 return (!refcount_is_zero(&ds->ds_longholds));
573 }
574
575 void
576 dsl_dataset_name(dsl_dataset_t *ds, char *name)
577 {
578 if (ds == NULL) {
579 (void) strcpy(name, "mos");
580 } else {
581 dsl_dir_name(ds->ds_dir, name);
582 VERIFY0(dsl_dataset_get_snapname(ds));
583 if (ds->ds_snapname[0]) {
584 (void) strcat(name, "@");
585 /*
586 * We use a "recursive" mutex so that we
587 * can call dprintf_ds() with ds_lock held.
588 */
589 if (!MUTEX_HELD(&ds->ds_lock)) {
590 mutex_enter(&ds->ds_lock);
591 (void) strcat(name, ds->ds_snapname);
592 mutex_exit(&ds->ds_lock);
593 } else {
594 (void) strcat(name, ds->ds_snapname);
595 }
596 }
597 }
598 }
599
600 void
601 dsl_dataset_rele(dsl_dataset_t *ds, void *tag)
602 {
603 dmu_buf_rele(ds->ds_dbuf, tag);
604 }
605
606 void
607 dsl_dataset_disown(dsl_dataset_t *ds, void *tag)
608 {
609 ASSERT(ds->ds_owner == tag && ds->ds_dbuf != NULL);
610
611 mutex_enter(&ds->ds_lock);
612 ds->ds_owner = NULL;
613 mutex_exit(&ds->ds_lock);
614 dsl_dataset_long_rele(ds, tag);
615 if (ds->ds_dbuf != NULL)
616 dsl_dataset_rele(ds, tag);
617 else
618 dsl_dataset_evict(NULL, ds);
619 }
620
621 boolean_t
622 dsl_dataset_tryown(dsl_dataset_t *ds, void *tag)
623 {
624 boolean_t gotit = FALSE;
625
626 mutex_enter(&ds->ds_lock);
627 if (ds->ds_owner == NULL && !DS_IS_INCONSISTENT(ds)) {
628 ds->ds_owner = tag;
629 dsl_dataset_long_hold(ds, tag);
630 gotit = TRUE;
631 }
632 mutex_exit(&ds->ds_lock);
633 return (gotit);
634 }
635
636 uint64_t
637 dsl_dataset_create_sync_dd(dsl_dir_t *dd, dsl_dataset_t *origin,
638 uint64_t flags, dmu_tx_t *tx)
639 {
640 dsl_pool_t *dp = dd->dd_pool;
641 dmu_buf_t *dbuf;
642 dsl_dataset_phys_t *dsphys;
643 uint64_t dsobj;
644 objset_t *mos = dp->dp_meta_objset;
645
646 if (origin == NULL)
647 origin = dp->dp_origin_snap;
648
649 ASSERT(origin == NULL || origin->ds_dir->dd_pool == dp);
650 ASSERT(origin == NULL || origin->ds_phys->ds_num_children > 0);
651 ASSERT(dmu_tx_is_syncing(tx));
652 ASSERT(dd->dd_phys->dd_head_dataset_obj == 0);
653
654 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0,
655 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx);
656 VERIFY0(dmu_bonus_hold(mos, dsobj, FTAG, &dbuf));
657 dmu_buf_will_dirty(dbuf, tx);
658 dsphys = dbuf->db_data;
659 bzero(dsphys, sizeof (dsl_dataset_phys_t));
660 dsphys->ds_dir_obj = dd->dd_object;
661 dsphys->ds_flags = flags;
662 dsphys->ds_fsid_guid = unique_create();
663 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid,
664 sizeof (dsphys->ds_guid));
665 dsphys->ds_snapnames_zapobj =
666 zap_create_norm(mos, U8_TEXTPREP_TOUPPER, DMU_OT_DSL_DS_SNAP_MAP,
667 DMU_OT_NONE, 0, tx);
668 dsphys->ds_creation_time = gethrestime_sec();
669 dsphys->ds_creation_txg = tx->tx_txg == TXG_INITIAL ? 1 : tx->tx_txg;
670
671 if (origin == NULL) {
672 dsphys->ds_deadlist_obj = dsl_deadlist_alloc(mos, tx);
673 } else {
674 dsl_dataset_t *ohds; /* head of the origin snapshot */
675
676 dsphys->ds_prev_snap_obj = origin->ds_object;
677 dsphys->ds_prev_snap_txg =
678 origin->ds_phys->ds_creation_txg;
679 dsphys->ds_referenced_bytes =
680 origin->ds_phys->ds_referenced_bytes;
681 dsphys->ds_compressed_bytes =
682 origin->ds_phys->ds_compressed_bytes;
683 dsphys->ds_uncompressed_bytes =
684 origin->ds_phys->ds_uncompressed_bytes;
685 dsphys->ds_bp = origin->ds_phys->ds_bp;
686 dsphys->ds_flags |= origin->ds_phys->ds_flags;
687
688 dmu_buf_will_dirty(origin->ds_dbuf, tx);
689 origin->ds_phys->ds_num_children++;
690
691 VERIFY0(dsl_dataset_hold_obj(dp,
692 origin->ds_dir->dd_phys->dd_head_dataset_obj, FTAG, &ohds));
693 dsphys->ds_deadlist_obj = dsl_deadlist_clone(&ohds->ds_deadlist,
694 dsphys->ds_prev_snap_txg, dsphys->ds_prev_snap_obj, tx);
695 dsl_dataset_rele(ohds, FTAG);
696
697 if (spa_version(dp->dp_spa) >= SPA_VERSION_NEXT_CLONES) {
698 if (origin->ds_phys->ds_next_clones_obj == 0) {
699 origin->ds_phys->ds_next_clones_obj =
700 zap_create(mos,
701 DMU_OT_NEXT_CLONES, DMU_OT_NONE, 0, tx);
702 }
703 VERIFY0(zap_add_int(mos,
704 origin->ds_phys->ds_next_clones_obj, dsobj, tx));
705 }
706
707 dmu_buf_will_dirty(dd->dd_dbuf, tx);
708 dd->dd_phys->dd_origin_obj = origin->ds_object;
709 if (spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) {
710 if (origin->ds_dir->dd_phys->dd_clones == 0) {
711 dmu_buf_will_dirty(origin->ds_dir->dd_dbuf, tx);
712 origin->ds_dir->dd_phys->dd_clones =
713 zap_create(mos,
714 DMU_OT_DSL_CLONES, DMU_OT_NONE, 0, tx);
715 }
716 VERIFY0(zap_add_int(mos,
717 origin->ds_dir->dd_phys->dd_clones, dsobj, tx));
718 }
719 }
720
721 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE)
722 dsphys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE;
723
724 dmu_buf_rele(dbuf, FTAG);
725
726 dmu_buf_will_dirty(dd->dd_dbuf, tx);
727 dd->dd_phys->dd_head_dataset_obj = dsobj;
728
729 return (dsobj);
730 }
731
732 static void
733 dsl_dataset_zero_zil(dsl_dataset_t *ds, dmu_tx_t *tx)
734 {
735 objset_t *os;
736
737 VERIFY0(dmu_objset_from_ds(ds, &os));
738 bzero(&os->os_zil_header, sizeof (os->os_zil_header));
739 dsl_dataset_dirty(ds, tx);
740 }
741
742 uint64_t
743 dsl_dataset_create_sync(dsl_dir_t *pdd, const char *lastname,
744 dsl_dataset_t *origin, uint64_t flags, cred_t *cr, dmu_tx_t *tx)
745 {
746 dsl_pool_t *dp = pdd->dd_pool;
747 uint64_t dsobj, ddobj;
748 dsl_dir_t *dd;
749
750 ASSERT(dmu_tx_is_syncing(tx));
751 ASSERT(lastname[0] != '@');
752
753 ddobj = dsl_dir_create_sync(dp, pdd, lastname, tx);
754 VERIFY0(dsl_dir_hold_obj(dp, ddobj, lastname, FTAG, &dd));
755
756 dsobj = dsl_dataset_create_sync_dd(dd, origin,
757 flags & ~DS_CREATE_FLAG_NODIRTY, tx);
758
759 dsl_deleg_set_create_perms(dd, tx, cr);
760
761 dsl_dir_rele(dd, FTAG);
762
763 /*
764 * If we are creating a clone, make sure we zero out any stale
765 * data from the origin snapshots zil header.
766 */
767 if (origin != NULL && !(flags & DS_CREATE_FLAG_NODIRTY)) {
768 dsl_dataset_t *ds;
769
770 VERIFY0(dsl_dataset_hold_obj(dp, dsobj, FTAG, &ds));
771 dsl_dataset_zero_zil(ds, tx);
772 dsl_dataset_rele(ds, FTAG);
773 }
774
775 return (dsobj);
776 }
777
778 /*
779 * The unique space in the head dataset can be calculated by subtracting
780 * the space used in the most recent snapshot, that is still being used
781 * in this file system, from the space currently in use. To figure out
782 * the space in the most recent snapshot still in use, we need to take
783 * the total space used in the snapshot and subtract out the space that
784 * has been freed up since the snapshot was taken.
785 */
786 void
787 dsl_dataset_recalc_head_uniq(dsl_dataset_t *ds)
788 {
789 uint64_t mrs_used;
790 uint64_t dlused, dlcomp, dluncomp;
791
792 ASSERT(!dsl_dataset_is_snapshot(ds));
793
794 if (ds->ds_phys->ds_prev_snap_obj != 0)
795 mrs_used = ds->ds_prev->ds_phys->ds_referenced_bytes;
796 else
797 mrs_used = 0;
798
799 dsl_deadlist_space(&ds->ds_deadlist, &dlused, &dlcomp, &dluncomp);
800
801 ASSERT3U(dlused, <=, mrs_used);
802 ds->ds_phys->ds_unique_bytes =
803 ds->ds_phys->ds_referenced_bytes - (mrs_used - dlused);
804
805 if (spa_version(ds->ds_dir->dd_pool->dp_spa) >=
806 SPA_VERSION_UNIQUE_ACCURATE)
807 ds->ds_phys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE;
808 }
809
810 void
811 dsl_dataset_remove_from_next_clones(dsl_dataset_t *ds, uint64_t obj,
812 dmu_tx_t *tx)
813 {
814 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
815 uint64_t count;
816 int err;
817
818 ASSERT(ds->ds_phys->ds_num_children >= 2);
819 err = zap_remove_int(mos, ds->ds_phys->ds_next_clones_obj, obj, tx);
820 /*
821 * The err should not be ENOENT, but a bug in a previous version
822 * of the code could cause upgrade_clones_cb() to not set
823 * ds_next_snap_obj when it should, leading to a missing entry.
824 * If we knew that the pool was created after
825 * SPA_VERSION_NEXT_CLONES, we could assert that it isn't
826 * ENOENT. However, at least we can check that we don't have
827 * too many entries in the next_clones_obj even after failing to
828 * remove this one.
829 */
830 if (err != ENOENT)
831 VERIFY0(err);
832 ASSERT0(zap_count(mos, ds->ds_phys->ds_next_clones_obj,
833 &count));
834 ASSERT3U(count, <=, ds->ds_phys->ds_num_children - 2);
835 }
836
837
838 blkptr_t *
839 dsl_dataset_get_blkptr(dsl_dataset_t *ds)
840 {
841 return (&ds->ds_phys->ds_bp);
842 }
843
844 void
845 dsl_dataset_set_blkptr(dsl_dataset_t *ds, blkptr_t *bp, dmu_tx_t *tx)
846 {
847 ASSERT(dmu_tx_is_syncing(tx));
848 /* If it's the meta-objset, set dp_meta_rootbp */
849 if (ds == NULL) {
850 tx->tx_pool->dp_meta_rootbp = *bp;
851 } else {
852 dmu_buf_will_dirty(ds->ds_dbuf, tx);
853 ds->ds_phys->ds_bp = *bp;
854 }
855 }
856
857 spa_t *
858 dsl_dataset_get_spa(dsl_dataset_t *ds)
859 {
860 return (ds->ds_dir->dd_pool->dp_spa);
861 }
862
863 void
864 dsl_dataset_dirty(dsl_dataset_t *ds, dmu_tx_t *tx)
865 {
866 dsl_pool_t *dp;
867
868 if (ds == NULL) /* this is the meta-objset */
869 return;
870
871 ASSERT(ds->ds_objset != NULL);
872
873 if (ds->ds_phys->ds_next_snap_obj != 0)
874 panic("dirtying snapshot!");
875
876 dp = ds->ds_dir->dd_pool;
877
878 if (txg_list_add(&dp->dp_dirty_datasets, ds, tx->tx_txg)) {
879 /* up the hold count until we can be written out */
880 dmu_buf_add_ref(ds->ds_dbuf, ds);
881 }
882 }
883
884 boolean_t
885 dsl_dataset_is_dirty(dsl_dataset_t *ds)
886 {
887 for (int t = 0; t < TXG_SIZE; t++) {
888 if (txg_list_member(&ds->ds_dir->dd_pool->dp_dirty_datasets,
889 ds, t))
890 return (B_TRUE);
891 }
892 return (B_FALSE);
893 }
894
895 static int
896 dsl_dataset_snapshot_reserve_space(dsl_dataset_t *ds, dmu_tx_t *tx)
897 {
898 uint64_t asize;
899
900 if (!dmu_tx_is_syncing(tx))
901 return (0);
902
903 /*
904 * If there's an fs-only reservation, any blocks that might become
905 * owned by the snapshot dataset must be accommodated by space
906 * outside of the reservation.
907 */
908 ASSERT(ds->ds_reserved == 0 || DS_UNIQUE_IS_ACCURATE(ds));
909 asize = MIN(ds->ds_phys->ds_unique_bytes, ds->ds_reserved);
910 if (asize > dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE))
911 return (SET_ERROR(ENOSPC));
912
913 /*
914 * Propagate any reserved space for this snapshot to other
915 * snapshot checks in this sync group.
916 */
917 if (asize > 0)
918 dsl_dir_willuse_space(ds->ds_dir, asize, tx);
919
920 return (0);
921 }
922
923 typedef struct dsl_dataset_snapshot_arg {
924 nvlist_t *ddsa_snaps;
925 nvlist_t *ddsa_props;
926 nvlist_t *ddsa_errors;
927 } dsl_dataset_snapshot_arg_t;
928
929 int
930 dsl_dataset_snapshot_check_impl(dsl_dataset_t *ds, const char *snapname,
931 dmu_tx_t *tx, boolean_t recv)
932 {
933 int error;
934 uint64_t value;
935
936 ds->ds_trysnap_txg = tx->tx_txg;
937
938 if (!dmu_tx_is_syncing(tx))
939 return (0);
940
941 /*
942 * We don't allow multiple snapshots of the same txg. If there
943 * is already one, try again.
944 */
945 if (ds->ds_phys->ds_prev_snap_txg >= tx->tx_txg)
946 return (SET_ERROR(EAGAIN));
947
948 /*
949 * Check for conflicting snapshot name.
950 */
951 error = dsl_dataset_snap_lookup(ds, snapname, &value);
952 if (error == 0)
953 return (SET_ERROR(EEXIST));
954 if (error != ENOENT)
955 return (error);
956
957 /*
958 * We don't allow taking snapshots of inconsistent datasets, such as
959 * those into which we are currently receiving. However, if we are
960 * creating this snapshot as part of a receive, this check will be
961 * executed atomically with respect to the completion of the receive
962 * itself but prior to the clearing of DS_FLAG_INCONSISTENT; in this
963 * case we ignore this, knowing it will be fixed up for us shortly in
964 * dmu_recv_end_sync().
965 */
966 if (!recv && DS_IS_INCONSISTENT(ds))
967 return (SET_ERROR(EBUSY));
968
969 error = dsl_dataset_snapshot_reserve_space(ds, tx);
970 if (error != 0)
971 return (error);
972
973 return (0);
974 }
975
976 static int
977 dsl_dataset_snapshot_check(void *arg, dmu_tx_t *tx)
978 {
979 dsl_dataset_snapshot_arg_t *ddsa = arg;
980 dsl_pool_t *dp = dmu_tx_pool(tx);
981 nvpair_t *pair;
982 int rv = 0;
983
984 for (pair = nvlist_next_nvpair(ddsa->ddsa_snaps, NULL);
985 pair != NULL; pair = nvlist_next_nvpair(ddsa->ddsa_snaps, pair)) {
986 int error = 0;
987 dsl_dataset_t *ds;
988 char *name, *atp;
989 char dsname[MAXNAMELEN];
990
991 name = nvpair_name(pair);
992 if (strlen(name) >= MAXNAMELEN)
993 error = SET_ERROR(ENAMETOOLONG);
994 if (error == 0) {
995 atp = strchr(name, '@');
996 if (atp == NULL)
997 error = SET_ERROR(EINVAL);
998 if (error == 0)
999 (void) strlcpy(dsname, name, atp - name + 1);
1000 }
1001 if (error == 0)
1002 error = dsl_dataset_hold(dp, dsname, FTAG, &ds);
1003 if (error == 0) {
1004 error = dsl_dataset_snapshot_check_impl(ds,
1005 atp + 1, tx, B_FALSE);
1006 dsl_dataset_rele(ds, FTAG);
1007 }
1008
1009 if (error != 0) {
1010 if (ddsa->ddsa_errors != NULL) {
1011 fnvlist_add_int32(ddsa->ddsa_errors,
1012 name, error);
1013 }
1014 rv = error;
1015 }
1016 }
1017 return (rv);
1018 }
1019
1020 void
1021 dsl_dataset_snapshot_sync_impl(dsl_dataset_t *ds, const char *snapname,
1022 dmu_tx_t *tx)
1023 {
1024 static zil_header_t zero_zil;
1025
1026 dsl_pool_t *dp = ds->ds_dir->dd_pool;
1027 dmu_buf_t *dbuf;
1028 dsl_dataset_phys_t *dsphys;
1029 uint64_t dsobj, crtxg;
1030 objset_t *mos = dp->dp_meta_objset;
1031 objset_t *os;
1032
1033 ASSERT(RRW_WRITE_HELD(&dp->dp_config_rwlock));
1034
1035 /*
1036 * If we are on an old pool, the zil must not be active, in which
1037 * case it will be zeroed. Usually zil_suspend() accomplishes this.
1038 */
1039 ASSERT(spa_version(dmu_tx_pool(tx)->dp_spa) >= SPA_VERSION_FAST_SNAP ||
1040 dmu_objset_from_ds(ds, &os) != 0 ||
1041 bcmp(&os->os_phys->os_zil_header, &zero_zil,
1042 sizeof (zero_zil)) == 0);
1043
1044
1045 /*
1046 * The origin's ds_creation_txg has to be < TXG_INITIAL
1047 */
1048 if (strcmp(snapname, ORIGIN_DIR_NAME) == 0)
1049 crtxg = 1;
1050 else
1051 crtxg = tx->tx_txg;
1052
1053 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0,
1054 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx);
1055 VERIFY0(dmu_bonus_hold(mos, dsobj, FTAG, &dbuf));
1056 dmu_buf_will_dirty(dbuf, tx);
1057 dsphys = dbuf->db_data;
1058 bzero(dsphys, sizeof (dsl_dataset_phys_t));
1059 dsphys->ds_dir_obj = ds->ds_dir->dd_object;
1060 dsphys->ds_fsid_guid = unique_create();
1061 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid,
1062 sizeof (dsphys->ds_guid));
1063 dsphys->ds_prev_snap_obj = ds->ds_phys->ds_prev_snap_obj;
1064 dsphys->ds_prev_snap_txg = ds->ds_phys->ds_prev_snap_txg;
1065 dsphys->ds_next_snap_obj = ds->ds_object;
1066 dsphys->ds_num_children = 1;
1067 dsphys->ds_creation_time = gethrestime_sec();
1068 dsphys->ds_creation_txg = crtxg;
1069 dsphys->ds_deadlist_obj = ds->ds_phys->ds_deadlist_obj;
1070 dsphys->ds_referenced_bytes = ds->ds_phys->ds_referenced_bytes;
1071 dsphys->ds_compressed_bytes = ds->ds_phys->ds_compressed_bytes;
1072 dsphys->ds_uncompressed_bytes = ds->ds_phys->ds_uncompressed_bytes;
1073 dsphys->ds_flags = ds->ds_phys->ds_flags;
1074 dsphys->ds_bp = ds->ds_phys->ds_bp;
1075 dmu_buf_rele(dbuf, FTAG);
1076
1077 ASSERT3U(ds->ds_prev != 0, ==, ds->ds_phys->ds_prev_snap_obj != 0);
1078 if (ds->ds_prev) {
1079 uint64_t next_clones_obj =
1080 ds->ds_prev->ds_phys->ds_next_clones_obj;
1081 ASSERT(ds->ds_prev->ds_phys->ds_next_snap_obj ==
1082 ds->ds_object ||
1083 ds->ds_prev->ds_phys->ds_num_children > 1);
1084 if (ds->ds_prev->ds_phys->ds_next_snap_obj == ds->ds_object) {
1085 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx);
1086 ASSERT3U(ds->ds_phys->ds_prev_snap_txg, ==,
1087 ds->ds_prev->ds_phys->ds_creation_txg);
1088 ds->ds_prev->ds_phys->ds_next_snap_obj = dsobj;
1089 } else if (next_clones_obj != 0) {
1090 dsl_dataset_remove_from_next_clones(ds->ds_prev,
1091 dsphys->ds_next_snap_obj, tx);
1092 VERIFY0(zap_add_int(mos,
1093 next_clones_obj, dsobj, tx));
1094 }
1095 }
1096
1097 /*
1098 * If we have a reference-reservation on this dataset, we will
1099 * need to increase the amount of refreservation being charged
1100 * since our unique space is going to zero.
1101 */
1102 if (ds->ds_reserved) {
1103 int64_t delta;
1104 ASSERT(DS_UNIQUE_IS_ACCURATE(ds));
1105 delta = MIN(ds->ds_phys->ds_unique_bytes, ds->ds_reserved);
1106 dsl_dir_diduse_space(ds->ds_dir, DD_USED_REFRSRV,
1107 delta, 0, 0, tx);
1108 }
1109
1110 dmu_buf_will_dirty(ds->ds_dbuf, tx);
1111 ds->ds_phys->ds_deadlist_obj = dsl_deadlist_clone(&ds->ds_deadlist,
1112 UINT64_MAX, ds->ds_phys->ds_prev_snap_obj, tx);
1113 dsl_deadlist_close(&ds->ds_deadlist);
1114 dsl_deadlist_open(&ds->ds_deadlist, mos, ds->ds_phys->ds_deadlist_obj);
1115 dsl_deadlist_add_key(&ds->ds_deadlist,
1116 ds->ds_phys->ds_prev_snap_txg, tx);
1117
1118 ASSERT3U(ds->ds_phys->ds_prev_snap_txg, <, tx->tx_txg);
1119 ds->ds_phys->ds_prev_snap_obj = dsobj;
1120 ds->ds_phys->ds_prev_snap_txg = crtxg;
1121 ds->ds_phys->ds_unique_bytes = 0;
1122 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE)
1123 ds->ds_phys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE;
1124
1125 VERIFY0(zap_add(mos, ds->ds_phys->ds_snapnames_zapobj,
1126 snapname, 8, 1, &dsobj, tx));
1127
1128 if (ds->ds_prev)
1129 dsl_dataset_rele(ds->ds_prev, ds);
1130 VERIFY0(dsl_dataset_hold_obj(dp,
1131 ds->ds_phys->ds_prev_snap_obj, ds, &ds->ds_prev));
1132
1133 dsl_scan_ds_snapshotted(ds, tx);
1134
1135 dsl_dir_snap_cmtime_update(ds->ds_dir);
1136
1137 spa_history_log_internal_ds(ds->ds_prev, "snapshot", tx, "");
1138 }
1139
1140 static void
1141 dsl_dataset_snapshot_sync(void *arg, dmu_tx_t *tx)
1142 {
1143 dsl_dataset_snapshot_arg_t *ddsa = arg;
1144 dsl_pool_t *dp = dmu_tx_pool(tx);
1145 nvpair_t *pair;
1146
1147 for (pair = nvlist_next_nvpair(ddsa->ddsa_snaps, NULL);
1148 pair != NULL; pair = nvlist_next_nvpair(ddsa->ddsa_snaps, pair)) {
1149 dsl_dataset_t *ds;
1150 char *name, *atp;
1151 char dsname[MAXNAMELEN];
1152
1153 name = nvpair_name(pair);
1154 atp = strchr(name, '@');
1155 (void) strlcpy(dsname, name, atp - name + 1);
1156 VERIFY0(dsl_dataset_hold(dp, dsname, FTAG, &ds));
1157
1158 dsl_dataset_snapshot_sync_impl(ds, atp + 1, tx);
1159 if (ddsa->ddsa_props != NULL) {
1160 dsl_props_set_sync_impl(ds->ds_prev,
1161 ZPROP_SRC_LOCAL, ddsa->ddsa_props, tx);
1162 }
1163 dsl_dataset_rele(ds, FTAG);
1164 }
1165 }
1166
1167 /*
1168 * The snapshots must all be in the same pool.
1169 * All-or-nothing: if there are any failures, nothing will be modified.
1170 */
1171 int
1172 dsl_dataset_snapshot(nvlist_t *snaps, nvlist_t *props, nvlist_t *errors)
1173 {
1174 dsl_dataset_snapshot_arg_t ddsa;
1175 nvpair_t *pair;
1176 boolean_t needsuspend;
1177 int error;
1178 spa_t *spa;
1179 char *firstname;
1180 nvlist_t *suspended = NULL;
1181
1182 pair = nvlist_next_nvpair(snaps, NULL);
1183 if (pair == NULL)
1184 return (0);
1185 firstname = nvpair_name(pair);
1186
1187 error = spa_open(firstname, &spa, FTAG);
1188 if (error != 0)
1189 return (error);
1190 needsuspend = (spa_version(spa) < SPA_VERSION_FAST_SNAP);
1191 spa_close(spa, FTAG);
1192
1193 if (needsuspend) {
1194 suspended = fnvlist_alloc();
1195 for (pair = nvlist_next_nvpair(snaps, NULL); pair != NULL;
1196 pair = nvlist_next_nvpair(snaps, pair)) {
1197 char fsname[MAXNAMELEN];
1198 char *snapname = nvpair_name(pair);
1199 char *atp;
1200 void *cookie;
1201
1202 atp = strchr(snapname, '@');
1203 if (atp == NULL) {
1204 error = SET_ERROR(EINVAL);
1205 break;
1206 }
1207 (void) strlcpy(fsname, snapname, atp - snapname + 1);
1208
1209 error = zil_suspend(fsname, &cookie);
1210 if (error != 0)
1211 break;
1212 fnvlist_add_uint64(suspended, fsname,
1213 (uintptr_t)cookie);
1214 }
1215 }
1216
1217 ddsa.ddsa_snaps = snaps;
1218 ddsa.ddsa_props = props;
1219 ddsa.ddsa_errors = errors;
1220
1221 if (error == 0) {
1222 error = dsl_sync_task(firstname, dsl_dataset_snapshot_check,
1223 dsl_dataset_snapshot_sync, &ddsa,
1224 fnvlist_num_pairs(snaps) * 3);
1225 }
1226
1227 if (suspended != NULL) {
1228 for (pair = nvlist_next_nvpair(suspended, NULL); pair != NULL;
1229 pair = nvlist_next_nvpair(suspended, pair)) {
1230 zil_resume((void *)(uintptr_t)
1231 fnvpair_value_uint64(pair));
1232 }
1233 fnvlist_free(suspended);
1234 }
1235
1236 return (error);
1237 }
1238
1239 typedef struct dsl_dataset_snapshot_tmp_arg {
1240 const char *ddsta_fsname;
1241 const char *ddsta_snapname;
1242 minor_t ddsta_cleanup_minor;
1243 const char *ddsta_htag;
1244 } dsl_dataset_snapshot_tmp_arg_t;
1245
1246 static int
1247 dsl_dataset_snapshot_tmp_check(void *arg, dmu_tx_t *tx)
1248 {
1249 dsl_dataset_snapshot_tmp_arg_t *ddsta = arg;
1250 dsl_pool_t *dp = dmu_tx_pool(tx);
1251 dsl_dataset_t *ds;
1252 int error;
1253
1254 error = dsl_dataset_hold(dp, ddsta->ddsta_fsname, FTAG, &ds);
1255 if (error != 0)
1256 return (error);
1257
1258 error = dsl_dataset_snapshot_check_impl(ds, ddsta->ddsta_snapname,
1259 tx, B_FALSE);
1260 if (error != 0) {
1261 dsl_dataset_rele(ds, FTAG);
1262 return (error);
1263 }
1264
1265 if (spa_version(dp->dp_spa) < SPA_VERSION_USERREFS) {
1266 dsl_dataset_rele(ds, FTAG);
1267 return (SET_ERROR(ENOTSUP));
1268 }
1269 error = dsl_dataset_user_hold_check_one(NULL, ddsta->ddsta_htag,
1270 B_TRUE, tx);
1271 if (error != 0) {
1272 dsl_dataset_rele(ds, FTAG);
1273 return (error);
1274 }
1275
1276 dsl_dataset_rele(ds, FTAG);
1277 return (0);
1278 }
1279
1280 static void
1281 dsl_dataset_snapshot_tmp_sync(void *arg, dmu_tx_t *tx)
1282 {
1283 dsl_dataset_snapshot_tmp_arg_t *ddsta = arg;
1284 dsl_pool_t *dp = dmu_tx_pool(tx);
1285 dsl_dataset_t *ds;
1286
1287 VERIFY0(dsl_dataset_hold(dp, ddsta->ddsta_fsname, FTAG, &ds));
1288
1289 dsl_dataset_snapshot_sync_impl(ds, ddsta->ddsta_snapname, tx);
1290 dsl_dataset_user_hold_sync_one(ds->ds_prev, ddsta->ddsta_htag,
1291 ddsta->ddsta_cleanup_minor, gethrestime_sec(), tx);
1292 dsl_destroy_snapshot_sync_impl(ds->ds_prev, B_TRUE, tx);
1293
1294 dsl_dataset_rele(ds, FTAG);
1295 }
1296
1297 int
1298 dsl_dataset_snapshot_tmp(const char *fsname, const char *snapname,
1299 minor_t cleanup_minor, const char *htag)
1300 {
1301 dsl_dataset_snapshot_tmp_arg_t ddsta;
1302 int error;
1303 spa_t *spa;
1304 boolean_t needsuspend;
1305 void *cookie;
1306
1307 ddsta.ddsta_fsname = fsname;
1308 ddsta.ddsta_snapname = snapname;
1309 ddsta.ddsta_cleanup_minor = cleanup_minor;
1310 ddsta.ddsta_htag = htag;
1311
1312 error = spa_open(fsname, &spa, FTAG);
1313 if (error != 0)
1314 return (error);
1315 needsuspend = (spa_version(spa) < SPA_VERSION_FAST_SNAP);
1316 spa_close(spa, FTAG);
1317
1318 if (needsuspend) {
1319 error = zil_suspend(fsname, &cookie);
1320 if (error != 0)
1321 return (error);
1322 }
1323
1324 error = dsl_sync_task(fsname, dsl_dataset_snapshot_tmp_check,
1325 dsl_dataset_snapshot_tmp_sync, &ddsta, 3);
1326
1327 if (needsuspend)
1328 zil_resume(cookie);
1329 return (error);
1330 }
1331
1332
1333 void
1334 dsl_dataset_sync(dsl_dataset_t *ds, zio_t *zio, dmu_tx_t *tx)
1335 {
1336 ASSERT(dmu_tx_is_syncing(tx));
1337 ASSERT(ds->ds_objset != NULL);
1338 ASSERT(ds->ds_phys->ds_next_snap_obj == 0);
1339
1340 /*
1341 * in case we had to change ds_fsid_guid when we opened it,
1342 * sync it out now.
1343 */
1344 dmu_buf_will_dirty(ds->ds_dbuf, tx);
1345 ds->ds_phys->ds_fsid_guid = ds->ds_fsid_guid;
1346
1347 dmu_objset_sync(ds->ds_objset, zio, tx);
1348 }
1349
1350 static void
1351 get_clones_stat(dsl_dataset_t *ds, nvlist_t *nv)
1352 {
1353 uint64_t count = 0;
1354 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
1355 zap_cursor_t zc;
1356 zap_attribute_t za;
1357 nvlist_t *propval = fnvlist_alloc();
1358 nvlist_t *val = fnvlist_alloc();
1359
1360 ASSERT(dsl_pool_config_held(ds->ds_dir->dd_pool));
1361
1362 /*
1363 * There may be missing entries in ds_next_clones_obj
1364 * due to a bug in a previous version of the code.
1365 * Only trust it if it has the right number of entries.
1366 */
1367 if (ds->ds_phys->ds_next_clones_obj != 0) {
1368 VERIFY0(zap_count(mos, ds->ds_phys->ds_next_clones_obj,
1369 &count));
1370 }
1371 if (count != ds->ds_phys->ds_num_children - 1)
1372 goto fail;
1373 for (zap_cursor_init(&zc, mos, ds->ds_phys->ds_next_clones_obj);
1374 zap_cursor_retrieve(&zc, &za) == 0;
1375 zap_cursor_advance(&zc)) {
1376 dsl_dataset_t *clone;
1377 char buf[ZFS_MAXNAMELEN];
1378 VERIFY0(dsl_dataset_hold_obj(ds->ds_dir->dd_pool,
1379 za.za_first_integer, FTAG, &clone));
1380 dsl_dir_name(clone->ds_dir, buf);
1381 fnvlist_add_boolean(val, buf);
1382 dsl_dataset_rele(clone, FTAG);
1383 }
1384 zap_cursor_fini(&zc);
1385 fnvlist_add_nvlist(propval, ZPROP_VALUE, val);
1386 fnvlist_add_nvlist(nv, zfs_prop_to_name(ZFS_PROP_CLONES), propval);
1387 fail:
1388 nvlist_free(val);
1389 nvlist_free(propval);
1390 }
1391
1392 void
1393 dsl_dataset_stats(dsl_dataset_t *ds, nvlist_t *nv)
1394 {
1395 dsl_pool_t *dp = ds->ds_dir->dd_pool;
1396 uint64_t refd, avail, uobjs, aobjs, ratio;
1397
1398 ASSERT(dsl_pool_config_held(dp));
1399
1400 ratio = ds->ds_phys->ds_compressed_bytes == 0 ? 100 :
1401 (ds->ds_phys->ds_uncompressed_bytes * 100 /
1402 ds->ds_phys->ds_compressed_bytes);
1403
1404 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFRATIO, ratio);
1405 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_LOGICALREFERENCED,
1406 ds->ds_phys->ds_uncompressed_bytes);
1407
1408 if (dsl_dataset_is_snapshot(ds)) {
1409 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_COMPRESSRATIO, ratio);
1410 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USED,
1411 ds->ds_phys->ds_unique_bytes);
1412 get_clones_stat(ds, nv);
1413 } else {
1414 dsl_dir_stats(ds->ds_dir, nv);
1415 }
1416
1417 dsl_dataset_space(ds, &refd, &avail, &uobjs, &aobjs);
1418 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_AVAILABLE, avail);
1419 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFERENCED, refd);
1420
1421 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATION,
1422 ds->ds_phys->ds_creation_time);
1423 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATETXG,
1424 ds->ds_phys->ds_creation_txg);
1425 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFQUOTA,
1426 ds->ds_quota);
1427 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFRESERVATION,
1428 ds->ds_reserved);
1429 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_GUID,
1430 ds->ds_phys->ds_guid);
1431 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_UNIQUE,
1432 ds->ds_phys->ds_unique_bytes);
1433 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_OBJSETID,
1434 ds->ds_object);
1435 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USERREFS,
1436 ds->ds_userrefs);
1437 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_DEFER_DESTROY,
1438 DS_IS_DEFER_DESTROY(ds) ? 1 : 0);
1439
1440 if (ds->ds_phys->ds_prev_snap_obj != 0) {
1441 uint64_t written, comp, uncomp;
1442 dsl_pool_t *dp = ds->ds_dir->dd_pool;
1443 dsl_dataset_t *prev;
1444
1445 int err = dsl_dataset_hold_obj(dp,
1446 ds->ds_phys->ds_prev_snap_obj, FTAG, &prev);
1447 if (err == 0) {
1448 err = dsl_dataset_space_written(prev, ds, &written,
1449 &comp, &uncomp);
1450 dsl_dataset_rele(prev, FTAG);
1451 if (err == 0) {
1452 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_WRITTEN,
1453 written);
1454 }
1455 }
1456 }
1457 }
1458
1459 void
1460 dsl_dataset_fast_stat(dsl_dataset_t *ds, dmu_objset_stats_t *stat)
1461 {
1462 dsl_pool_t *dp = ds->ds_dir->dd_pool;
1463 ASSERT(dsl_pool_config_held(dp));
1464
1465 stat->dds_creation_txg = ds->ds_phys->ds_creation_txg;
1466 stat->dds_inconsistent = ds->ds_phys->ds_flags & DS_FLAG_INCONSISTENT;
1467 stat->dds_guid = ds->ds_phys->ds_guid;
1468 stat->dds_origin[0] = '\0';
1469 if (dsl_dataset_is_snapshot(ds)) {
1470 stat->dds_is_snapshot = B_TRUE;
1471 stat->dds_num_clones = ds->ds_phys->ds_num_children - 1;
1472 } else {
1473 stat->dds_is_snapshot = B_FALSE;
1474 stat->dds_num_clones = 0;
1475
1476 if (dsl_dir_is_clone(ds->ds_dir)) {
1477 dsl_dataset_t *ods;
1478
1479 VERIFY0(dsl_dataset_hold_obj(dp,
1480 ds->ds_dir->dd_phys->dd_origin_obj, FTAG, &ods));
1481 dsl_dataset_name(ods, stat->dds_origin);
1482 dsl_dataset_rele(ods, FTAG);
1483 }
1484 }
1485 }
1486
1487 uint64_t
1488 dsl_dataset_fsid_guid(dsl_dataset_t *ds)
1489 {
1490 return (ds->ds_fsid_guid);
1491 }
1492
1493 void
1494 dsl_dataset_space(dsl_dataset_t *ds,
1495 uint64_t *refdbytesp, uint64_t *availbytesp,
1496 uint64_t *usedobjsp, uint64_t *availobjsp)
1497 {
1498 *refdbytesp = ds->ds_phys->ds_referenced_bytes;
1499 *availbytesp = dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE);
1500 if (ds->ds_reserved > ds->ds_phys->ds_unique_bytes)
1501 *availbytesp += ds->ds_reserved - ds->ds_phys->ds_unique_bytes;
1502 if (ds->ds_quota != 0) {
1503 /*
1504 * Adjust available bytes according to refquota
1505 */
1506 if (*refdbytesp < ds->ds_quota)
1507 *availbytesp = MIN(*availbytesp,
1508 ds->ds_quota - *refdbytesp);
1509 else
1510 *availbytesp = 0;
1511 }
1512 *usedobjsp = ds->ds_phys->ds_bp.blk_fill;
1513 *availobjsp = DN_MAX_OBJECT - *usedobjsp;
1514 }
1515
1516 boolean_t
1517 dsl_dataset_modified_since_snap(dsl_dataset_t *ds, dsl_dataset_t *snap)
1518 {
1519 dsl_pool_t *dp = ds->ds_dir->dd_pool;
1520
1521 ASSERT(dsl_pool_config_held(dp));
1522 if (snap == NULL)
1523 return (B_FALSE);
1524 if (ds->ds_phys->ds_bp.blk_birth >
1525 snap->ds_phys->ds_creation_txg) {
1526 objset_t *os, *os_snap;
1527 /*
1528 * It may be that only the ZIL differs, because it was
1529 * reset in the head. Don't count that as being
1530 * modified.
1531 */
1532 if (dmu_objset_from_ds(ds, &os) != 0)
1533 return (B_TRUE);
1534 if (dmu_objset_from_ds(snap, &os_snap) != 0)
1535 return (B_TRUE);
1536 return (bcmp(&os->os_phys->os_meta_dnode,
1537 &os_snap->os_phys->os_meta_dnode,
1538 sizeof (os->os_phys->os_meta_dnode)) != 0);
1539 }
1540 return (B_FALSE);
1541 }
1542
1543 typedef struct dsl_dataset_rename_snapshot_arg {
1544 const char *ddrsa_fsname;
1545 const char *ddrsa_oldsnapname;
1546 const char *ddrsa_newsnapname;
1547 boolean_t ddrsa_recursive;
1548 dmu_tx_t *ddrsa_tx;
1549 } dsl_dataset_rename_snapshot_arg_t;
1550
1551 /* ARGSUSED */
1552 static int
1553 dsl_dataset_rename_snapshot_check_impl(dsl_pool_t *dp,
1554 dsl_dataset_t *hds, void *arg)
1555 {
1556 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg;
1557 int error;
1558 uint64_t val;
1559
1560 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_oldsnapname, &val);
1561 if (error != 0) {
1562 /* ignore nonexistent snapshots */
1563 return (error == ENOENT ? 0 : error);
1564 }
1565
1566 /* new name should not exist */
1567 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_newsnapname, &val);
1568 if (error == 0)
1569 error = SET_ERROR(EEXIST);
1570 else if (error == ENOENT)
1571 error = 0;
1572
1573 /* dataset name + 1 for the "@" + the new snapshot name must fit */
1574 if (dsl_dir_namelen(hds->ds_dir) + 1 +
1575 strlen(ddrsa->ddrsa_newsnapname) >= MAXNAMELEN)
1576 error = SET_ERROR(ENAMETOOLONG);
1577
1578 return (error);
1579 }
1580
1581 static int
1582 dsl_dataset_rename_snapshot_check(void *arg, dmu_tx_t *tx)
1583 {
1584 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg;
1585 dsl_pool_t *dp = dmu_tx_pool(tx);
1586 dsl_dataset_t *hds;
1587 int error;
1588
1589 error = dsl_dataset_hold(dp, ddrsa->ddrsa_fsname, FTAG, &hds);
1590 if (error != 0)
1591 return (error);
1592
1593 if (ddrsa->ddrsa_recursive) {
1594 error = dmu_objset_find_dp(dp, hds->ds_dir->dd_object,
1595 dsl_dataset_rename_snapshot_check_impl, ddrsa,
1596 DS_FIND_CHILDREN);
1597 } else {
1598 error = dsl_dataset_rename_snapshot_check_impl(dp, hds, ddrsa);
1599 }
1600 dsl_dataset_rele(hds, FTAG);
1601 return (error);
1602 }
1603
1604 static int
1605 dsl_dataset_rename_snapshot_sync_impl(dsl_pool_t *dp,
1606 dsl_dataset_t *hds, void *arg)
1607 {
1608 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg;
1609 dsl_dataset_t *ds;
1610 uint64_t val;
1611 dmu_tx_t *tx = ddrsa->ddrsa_tx;
1612 int error;
1613
1614 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_oldsnapname, &val);
1615 ASSERT(error == 0 || error == ENOENT);
1616 if (error == ENOENT) {
1617 /* ignore nonexistent snapshots */
1618 return (0);
1619 }
1620
1621 VERIFY0(dsl_dataset_hold_obj(dp, val, FTAG, &ds));
1622
1623 /* log before we change the name */
1624 spa_history_log_internal_ds(ds, "rename", tx,
1625 "-> @%s", ddrsa->ddrsa_newsnapname);
1626
1627 VERIFY0(dsl_dataset_snap_remove(hds, ddrsa->ddrsa_oldsnapname, tx));
1628 mutex_enter(&ds->ds_lock);
1629 (void) strcpy(ds->ds_snapname, ddrsa->ddrsa_newsnapname);
1630 mutex_exit(&ds->ds_lock);
1631 VERIFY0(zap_add(dp->dp_meta_objset, hds->ds_phys->ds_snapnames_zapobj,
1632 ds->ds_snapname, 8, 1, &ds->ds_object, tx));
1633
1634 dsl_dataset_rele(ds, FTAG);
1635 return (0);
1636 }
1637
1638 static void
1639 dsl_dataset_rename_snapshot_sync(void *arg, dmu_tx_t *tx)
1640 {
1641 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg;
1642 dsl_pool_t *dp = dmu_tx_pool(tx);
1643 dsl_dataset_t *hds;
1644
1645 VERIFY0(dsl_dataset_hold(dp, ddrsa->ddrsa_fsname, FTAG, &hds));
1646 ddrsa->ddrsa_tx = tx;
1647 if (ddrsa->ddrsa_recursive) {
1648 VERIFY0(dmu_objset_find_dp(dp, hds->ds_dir->dd_object,
1649 dsl_dataset_rename_snapshot_sync_impl, ddrsa,
1650 DS_FIND_CHILDREN));
1651 } else {
1652 VERIFY0(dsl_dataset_rename_snapshot_sync_impl(dp, hds, ddrsa));
1653 }
1654 dsl_dataset_rele(hds, FTAG);
1655 }
1656
1657 int
1658 dsl_dataset_rename_snapshot(const char *fsname,
1659 const char *oldsnapname, const char *newsnapname, boolean_t recursive)
1660 {
1661 dsl_dataset_rename_snapshot_arg_t ddrsa;
1662
1663 ddrsa.ddrsa_fsname = fsname;
1664 ddrsa.ddrsa_oldsnapname = oldsnapname;
1665 ddrsa.ddrsa_newsnapname = newsnapname;
1666 ddrsa.ddrsa_recursive = recursive;
1667
1668 return (dsl_sync_task(fsname, dsl_dataset_rename_snapshot_check,
1669 dsl_dataset_rename_snapshot_sync, &ddrsa, 1));
1670 }
1671
1672 /*
1673 * If we're doing an ownership handoff, we need to make sure that there is
1674 * only one long hold on the dataset. We're not allowed to change anything here
1675 * so we don't permanently release the long hold or regular hold here. We want
1676 * to do this only when syncing to avoid the dataset unexpectedly going away
1677 * when we release the long hold.
1678 */
1679 static int
1680 dsl_dataset_handoff_check(dsl_dataset_t *ds, void *owner, dmu_tx_t *tx)
1681 {
1682 boolean_t held;
1683
1684 if (!dmu_tx_is_syncing(tx))
1685 return (0);
1686
1687 if (owner != NULL) {
1688 VERIFY3P(ds->ds_owner, ==, owner);
1689 dsl_dataset_long_rele(ds, owner);
1690 }
1691
1692 held = dsl_dataset_long_held(ds);
1693
1694 if (owner != NULL)
1695 dsl_dataset_long_hold(ds, owner);
1696
1697 if (held)
1698 return (SET_ERROR(EBUSY));
1699
1700 return (0);
1701 }
1702
1703 typedef struct dsl_dataset_rollback_arg {
1704 const char *ddra_fsname;
1705 void *ddra_owner;
1706 nvlist_t *ddra_result;
1707 } dsl_dataset_rollback_arg_t;
1708
1709 static int
1710 dsl_dataset_rollback_check(void *arg, dmu_tx_t *tx)
1711 {
1712 dsl_dataset_rollback_arg_t *ddra = arg;
1713 dsl_pool_t *dp = dmu_tx_pool(tx);
1714 dsl_dataset_t *ds;
1715 int64_t unused_refres_delta;
1716 int error;
1717
1718 error = dsl_dataset_hold(dp, ddra->ddra_fsname, FTAG, &ds);
1719 if (error != 0)
1720 return (error);
1721
1722 /* must not be a snapshot */
1723 if (dsl_dataset_is_snapshot(ds)) {
1724 dsl_dataset_rele(ds, FTAG);
1725 return (SET_ERROR(EINVAL));
1726 }
1727
1728 /* must have a most recent snapshot */
1729 if (ds->ds_phys->ds_prev_snap_txg < TXG_INITIAL) {
1730 dsl_dataset_rele(ds, FTAG);
1731 return (SET_ERROR(EINVAL));
1732 }
1733
1734 /* must not have any bookmarks after the most recent snapshot */
1735 nvlist_t *proprequest = fnvlist_alloc();
1736 fnvlist_add_boolean(proprequest, zfs_prop_to_name(ZFS_PROP_CREATETXG));
1737 nvlist_t *bookmarks = fnvlist_alloc();
1738 error = dsl_get_bookmarks_impl(ds, proprequest, bookmarks);
1739 fnvlist_free(proprequest);
1740 if (error != 0)
1741 return (error);
1742 for (nvpair_t *pair = nvlist_next_nvpair(bookmarks, NULL);
1743 pair != NULL; pair = nvlist_next_nvpair(bookmarks, pair)) {
1744 nvlist_t *valuenv =
1745 fnvlist_lookup_nvlist(fnvpair_value_nvlist(pair),
1746 zfs_prop_to_name(ZFS_PROP_CREATETXG));
1747 uint64_t createtxg = fnvlist_lookup_uint64(valuenv, "value");
1748 if (createtxg > ds->ds_phys->ds_prev_snap_txg) {
1749 fnvlist_free(bookmarks);
1750 dsl_dataset_rele(ds, FTAG);
1751 return (SET_ERROR(EEXIST));
1752 }
1753 }
1754 fnvlist_free(bookmarks);
1755
1756 error = dsl_dataset_handoff_check(ds, ddra->ddra_owner, tx);
1757 if (error != 0) {
1758 dsl_dataset_rele(ds, FTAG);
1759 return (error);
1760 }
1761
1762 /*
1763 * Check if the snap we are rolling back to uses more than
1764 * the refquota.
1765 */
1766 if (ds->ds_quota != 0 &&
1767 ds->ds_prev->ds_phys->ds_referenced_bytes > ds->ds_quota) {
1768 dsl_dataset_rele(ds, FTAG);
1769 return (SET_ERROR(EDQUOT));
1770 }
1771
1772 /*
1773 * When we do the clone swap, we will temporarily use more space
1774 * due to the refreservation (the head will no longer have any
1775 * unique space, so the entire amount of the refreservation will need
1776 * to be free). We will immediately destroy the clone, freeing
1777 * this space, but the freeing happens over many txg's.
1778 */
1779 unused_refres_delta = (int64_t)MIN(ds->ds_reserved,
1780 ds->ds_phys->ds_unique_bytes);
1781
1782 if (unused_refres_delta > 0 &&
1783 unused_refres_delta >
1784 dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE)) {
1785 dsl_dataset_rele(ds, FTAG);
1786 return (SET_ERROR(ENOSPC));
1787 }
1788
1789 dsl_dataset_rele(ds, FTAG);
1790 return (0);
1791 }
1792
1793 static void
1794 dsl_dataset_rollback_sync(void *arg, dmu_tx_t *tx)
1795 {
1796 dsl_dataset_rollback_arg_t *ddra = arg;
1797 dsl_pool_t *dp = dmu_tx_pool(tx);
1798 dsl_dataset_t *ds, *clone;
1799 uint64_t cloneobj;
1800 char namebuf[ZFS_MAXNAMELEN];
1801
1802 VERIFY0(dsl_dataset_hold(dp, ddra->ddra_fsname, FTAG, &ds));
1803
1804 dsl_dataset_name(ds->ds_prev, namebuf);
1805 fnvlist_add_string(ddra->ddra_result, "target", namebuf);
1806
1807 cloneobj = dsl_dataset_create_sync(ds->ds_dir, "%rollback",
1808 ds->ds_prev, DS_CREATE_FLAG_NODIRTY, kcred, tx);
1809
1810 VERIFY0(dsl_dataset_hold_obj(dp, cloneobj, FTAG, &clone));
1811
1812 dsl_dataset_clone_swap_sync_impl(clone, ds, tx);
1813 dsl_dataset_zero_zil(ds, tx);
1814
1815 dsl_destroy_head_sync_impl(clone, tx);
1816
1817 dsl_dataset_rele(clone, FTAG);
1818 dsl_dataset_rele(ds, FTAG);
1819 }
1820
1821 /*
1822 * Rolls back the given filesystem or volume to the most recent snapshot.
1823 * The name of the most recent snapshot will be returned under key "target"
1824 * in the result nvlist.
1825 *
1826 * If owner != NULL:
1827 * - The existing dataset MUST be owned by the specified owner at entry
1828 * - Upon return, dataset will still be held by the same owner, whether we
1829 * succeed or not.
1830 *
1831 * This mode is required any time the existing filesystem is mounted. See
1832 * notes above zfs_suspend_fs() for further details.
1833 */
1834 int
1835 dsl_dataset_rollback(const char *fsname, void *owner, nvlist_t *result)
1836 {
1837 dsl_dataset_rollback_arg_t ddra;
1838
1839 ddra.ddra_fsname = fsname;
1840 ddra.ddra_owner = owner;
1841 ddra.ddra_result = result;
1842
1843 return (dsl_sync_task(fsname, dsl_dataset_rollback_check,
1844 dsl_dataset_rollback_sync, &ddra, 1));
1845 }
1846
1847 struct promotenode {
1848 list_node_t link;
1849 dsl_dataset_t *ds;
1850 };
1851
1852 typedef struct dsl_dataset_promote_arg {
1853 const char *ddpa_clonename;
1854 dsl_dataset_t *ddpa_clone;
1855 list_t shared_snaps, origin_snaps, clone_snaps;
1856 dsl_dataset_t *origin_origin; /* origin of the origin */
1857 uint64_t used, comp, uncomp, unique, cloneusedsnap, originusedsnap;
1858 char *err_ds;
1859 } dsl_dataset_promote_arg_t;
1860
1861 static int snaplist_space(list_t *l, uint64_t mintxg, uint64_t *spacep);
1862 static int promote_hold(dsl_dataset_promote_arg_t *ddpa, dsl_pool_t *dp,
1863 void *tag);
1864 static void promote_rele(dsl_dataset_promote_arg_t *ddpa, void *tag);
1865
1866 static int
1867 dsl_dataset_promote_check(void *arg, dmu_tx_t *tx)
1868 {
1869 dsl_dataset_promote_arg_t *ddpa = arg;
1870 dsl_pool_t *dp = dmu_tx_pool(tx);
1871 dsl_dataset_t *hds;
1872 struct promotenode *snap;
1873 dsl_dataset_t *origin_ds;
1874 int err;
1875 uint64_t unused;
1876
1877 err = promote_hold(ddpa, dp, FTAG);
1878 if (err != 0)
1879 return (err);
1880
1881 hds = ddpa->ddpa_clone;
1882
1883 if (hds->ds_phys->ds_flags & DS_FLAG_NOPROMOTE) {
1884 promote_rele(ddpa, FTAG);
1885 return (SET_ERROR(EXDEV));
1886 }
1887
1888 /*
1889 * Compute and check the amount of space to transfer. Since this is
1890 * so expensive, don't do the preliminary check.
1891 */
1892 if (!dmu_tx_is_syncing(tx)) {
1893 promote_rele(ddpa, FTAG);
1894 return (0);
1895 }
1896
1897 snap = list_head(&ddpa->shared_snaps);
1898 origin_ds = snap->ds;
1899
1900 /* compute origin's new unique space */
1901 snap = list_tail(&ddpa->clone_snaps);
1902 ASSERT3U(snap->ds->ds_phys->ds_prev_snap_obj, ==, origin_ds->ds_object);
1903 dsl_deadlist_space_range(&snap->ds->ds_deadlist,
1904 origin_ds->ds_phys->ds_prev_snap_txg, UINT64_MAX,
1905 &ddpa->unique, &unused, &unused);
1906
1907 /*
1908 * Walk the snapshots that we are moving
1909 *
1910 * Compute space to transfer. Consider the incremental changes
1911 * to used by each snapshot:
1912 * (my used) = (prev's used) + (blocks born) - (blocks killed)
1913 * So each snapshot gave birth to:
1914 * (blocks born) = (my used) - (prev's used) + (blocks killed)
1915 * So a sequence would look like:
1916 * (uN - u(N-1) + kN) + ... + (u1 - u0 + k1) + (u0 - 0 + k0)
1917 * Which simplifies to:
1918 * uN + kN + kN-1 + ... + k1 + k0
1919 * Note however, if we stop before we reach the ORIGIN we get:
1920 * uN + kN + kN-1 + ... + kM - uM-1
1921 */
1922 ddpa->used = origin_ds->ds_phys->ds_referenced_bytes;
1923 ddpa->comp = origin_ds->ds_phys->ds_compressed_bytes;
1924 ddpa->uncomp = origin_ds->ds_phys->ds_uncompressed_bytes;
1925 for (snap = list_head(&ddpa->shared_snaps); snap;
1926 snap = list_next(&ddpa->shared_snaps, snap)) {
1927 uint64_t val, dlused, dlcomp, dluncomp;
1928 dsl_dataset_t *ds = snap->ds;
1929
1930 /*
1931 * If there are long holds, we won't be able to evict
1932 * the objset.
1933 */
1934 if (dsl_dataset_long_held(ds)) {
1935 err = SET_ERROR(EBUSY);
1936 goto out;
1937 }
1938
1939 /* Check that the snapshot name does not conflict */
1940 VERIFY0(dsl_dataset_get_snapname(ds));
1941 err = dsl_dataset_snap_lookup(hds, ds->ds_snapname, &val);
1942 if (err == 0) {
1943 (void) strcpy(ddpa->err_ds, snap->ds->ds_snapname);
1944 err = SET_ERROR(EEXIST);
1945 goto out;
1946 }
1947 if (err != ENOENT)
1948 goto out;
1949
1950 /* The very first snapshot does not have a deadlist */
1951 if (ds->ds_phys->ds_prev_snap_obj == 0)
1952 continue;
1953
1954 dsl_deadlist_space(&ds->ds_deadlist,
1955 &dlused, &dlcomp, &dluncomp);
1956 ddpa->used += dlused;
1957 ddpa->comp += dlcomp;
1958 ddpa->uncomp += dluncomp;
1959 }
1960
1961 /*
1962 * If we are a clone of a clone then we never reached ORIGIN,
1963 * so we need to subtract out the clone origin's used space.
1964 */
1965 if (ddpa->origin_origin) {
1966 ddpa->used -= ddpa->origin_origin->ds_phys->ds_referenced_bytes;
1967 ddpa->comp -= ddpa->origin_origin->ds_phys->ds_compressed_bytes;
1968 ddpa->uncomp -=
1969 ddpa->origin_origin->ds_phys->ds_uncompressed_bytes;
1970 }
1971
1972 /* Check that there is enough space here */
1973 err = dsl_dir_transfer_possible(origin_ds->ds_dir, hds->ds_dir,
1974 ddpa->used);
1975 if (err != 0)
1976 goto out;
1977
1978 /*
1979 * Compute the amounts of space that will be used by snapshots
1980 * after the promotion (for both origin and clone). For each,
1981 * it is the amount of space that will be on all of their
1982 * deadlists (that was not born before their new origin).
1983 */
1984 if (hds->ds_dir->dd_phys->dd_flags & DD_FLAG_USED_BREAKDOWN) {
1985 uint64_t space;
1986
1987 /*
1988 * Note, typically this will not be a clone of a clone,
1989 * so dd_origin_txg will be < TXG_INITIAL, so
1990 * these snaplist_space() -> dsl_deadlist_space_range()
1991 * calls will be fast because they do not have to
1992 * iterate over all bps.
1993 */
1994 snap = list_head(&ddpa->origin_snaps);
1995 err = snaplist_space(&ddpa->shared_snaps,
1996 snap->ds->ds_dir->dd_origin_txg, &ddpa->cloneusedsnap);
1997 if (err != 0)
1998 goto out;
1999
2000 err = snaplist_space(&ddpa->clone_snaps,
2001 snap->ds->ds_dir->dd_origin_txg, &space);
2002 if (err != 0)
2003 goto out;
2004 ddpa->cloneusedsnap += space;
2005 }
2006 if (origin_ds->ds_dir->dd_phys->dd_flags & DD_FLAG_USED_BREAKDOWN) {
2007 err = snaplist_space(&ddpa->origin_snaps,
2008 origin_ds->ds_phys->ds_creation_txg, &ddpa->originusedsnap);
2009 if (err != 0)
2010 goto out;
2011 }
2012
2013 out:
2014 promote_rele(ddpa, FTAG);
2015 return (err);
2016 }
2017
2018 static void
2019 dsl_dataset_promote_sync(void *arg, dmu_tx_t *tx)
2020 {
2021 dsl_dataset_promote_arg_t *ddpa = arg;
2022 dsl_pool_t *dp = dmu_tx_pool(tx);
2023 dsl_dataset_t *hds;
2024 struct promotenode *snap;
2025 dsl_dataset_t *origin_ds;
2026 dsl_dataset_t *origin_head;
2027 dsl_dir_t *dd;
2028 dsl_dir_t *odd = NULL;
2029 uint64_t oldnext_obj;
2030 int64_t delta;
2031
2032 VERIFY0(promote_hold(ddpa, dp, FTAG));
2033 hds = ddpa->ddpa_clone;
2034
2035 ASSERT0(hds->ds_phys->ds_flags & DS_FLAG_NOPROMOTE);
2036
2037 snap = list_head(&ddpa->shared_snaps);
2038 origin_ds = snap->ds;
2039 dd = hds->ds_dir;
2040
2041 snap = list_head(&ddpa->origin_snaps);
2042 origin_head = snap->ds;
2043
2044 /*
2045 * We need to explicitly open odd, since origin_ds's dd will be
2046 * changing.
2047 */
2048 VERIFY0(dsl_dir_hold_obj(dp, origin_ds->ds_dir->dd_object,
2049 NULL, FTAG, &odd));
2050
2051 /* change origin's next snap */
2052 dmu_buf_will_dirty(origin_ds->ds_dbuf, tx);
2053 oldnext_obj = origin_ds->ds_phys->ds_next_snap_obj;
2054 snap = list_tail(&ddpa->clone_snaps);
2055 ASSERT3U(snap->ds->ds_phys->ds_prev_snap_obj, ==, origin_ds->ds_object);
2056 origin_ds->ds_phys->ds_next_snap_obj = snap->ds->ds_object;
2057
2058 /* change the origin's next clone */
2059 if (origin_ds->ds_phys->ds_next_clones_obj) {
2060 dsl_dataset_remove_from_next_clones(origin_ds,
2061 snap->ds->ds_object, tx);
2062 VERIFY0(zap_add_int(dp->dp_meta_objset,
2063 origin_ds->ds_phys->ds_next_clones_obj,
2064 oldnext_obj, tx));
2065 }
2066
2067 /* change origin */
2068 dmu_buf_will_dirty(dd->dd_dbuf, tx);
2069 ASSERT3U(dd->dd_phys->dd_origin_obj, ==, origin_ds->ds_object);
2070 dd->dd_phys->dd_origin_obj = odd->dd_phys->dd_origin_obj;
2071 dd->dd_origin_txg = origin_head->ds_dir->dd_origin_txg;
2072 dmu_buf_will_dirty(odd->dd_dbuf, tx);
2073 odd->dd_phys->dd_origin_obj = origin_ds->ds_object;
2074 origin_head->ds_dir->dd_origin_txg =
2075 origin_ds->ds_phys->ds_creation_txg;
2076
2077 /* change dd_clone entries */
2078 if (spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) {
2079 VERIFY0(zap_remove_int(dp->dp_meta_objset,
2080 odd->dd_phys->dd_clones, hds->ds_object, tx));
2081 VERIFY0(zap_add_int(dp->dp_meta_objset,
2082 ddpa->origin_origin->ds_dir->dd_phys->dd_clones,
2083 hds->ds_object, tx));
2084
2085 VERIFY0(zap_remove_int(dp->dp_meta_objset,
2086 ddpa->origin_origin->ds_dir->dd_phys->dd_clones,
2087 origin_head->ds_object, tx));
2088 if (dd->dd_phys->dd_clones == 0) {
2089 dd->dd_phys->dd_clones = zap_create(dp->dp_meta_objset,
2090 DMU_OT_DSL_CLONES, DMU_OT_NONE, 0, tx);
2091 }
2092 VERIFY0(zap_add_int(dp->dp_meta_objset,
2093 dd->dd_phys->dd_clones, origin_head->ds_object, tx));
2094 }
2095
2096 /* move snapshots to this dir */
2097 for (snap = list_head(&ddpa->shared_snaps); snap;
2098 snap = list_next(&ddpa->shared_snaps, snap)) {
2099 dsl_dataset_t *ds = snap->ds;
2100
2101 /*
2102 * Property callbacks are registered to a particular
2103 * dsl_dir. Since ours is changing, evict the objset
2104 * so that they will be unregistered from the old dsl_dir.
2105 */
2106 if (ds->ds_objset) {
2107 dmu_objset_evict(ds->ds_objset);
2108 ds->ds_objset = NULL;
2109 }
2110
2111 /* move snap name entry */
2112 VERIFY0(dsl_dataset_get_snapname(ds));
2113 VERIFY0(dsl_dataset_snap_remove(origin_head,
2114 ds->ds_snapname, tx));
2115 VERIFY0(zap_add(dp->dp_meta_objset,
2116 hds->ds_phys->ds_snapnames_zapobj, ds->ds_snapname,
2117 8, 1, &ds->ds_object, tx));
2118
2119 /* change containing dsl_dir */
2120 dmu_buf_will_dirty(ds->ds_dbuf, tx);
2121 ASSERT3U(ds->ds_phys->ds_dir_obj, ==, odd->dd_object);
2122 ds->ds_phys->ds_dir_obj = dd->dd_object;
2123 ASSERT3P(ds->ds_dir, ==, odd);
2124 dsl_dir_rele(ds->ds_dir, ds);
2125 VERIFY0(dsl_dir_hold_obj(dp, dd->dd_object,
2126 NULL, ds, &ds->ds_dir));
2127
2128 /* move any clone references */
2129 if (ds->ds_phys->ds_next_clones_obj &&
2130 spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) {
2131 zap_cursor_t zc;
2132 zap_attribute_t za;
2133
2134 for (zap_cursor_init(&zc, dp->dp_meta_objset,
2135 ds->ds_phys->ds_next_clones_obj);
2136 zap_cursor_retrieve(&zc, &za) == 0;
2137 zap_cursor_advance(&zc)) {
2138 dsl_dataset_t *cnds;
2139 uint64_t o;
2140
2141 if (za.za_first_integer == oldnext_obj) {
2142 /*
2143 * We've already moved the
2144 * origin's reference.
2145 */
2146 continue;
2147 }
2148
2149 VERIFY0(dsl_dataset_hold_obj(dp,
2150 za.za_first_integer, FTAG, &cnds));
2151 o = cnds->ds_dir->dd_phys->dd_head_dataset_obj;
2152
2153 VERIFY0(zap_remove_int(dp->dp_meta_objset,
2154 odd->dd_phys->dd_clones, o, tx));
2155 VERIFY0(zap_add_int(dp->dp_meta_objset,
2156 dd->dd_phys->dd_clones, o, tx));
2157 dsl_dataset_rele(cnds, FTAG);
2158 }
2159 zap_cursor_fini(&zc);
2160 }
2161
2162 ASSERT(!dsl_prop_hascb(ds));
2163 }
2164
2165 /*
2166 * Change space accounting.
2167 * Note, pa->*usedsnap and dd_used_breakdown[SNAP] will either
2168 * both be valid, or both be 0 (resulting in delta == 0). This
2169 * is true for each of {clone,origin} independently.
2170 */
2171
2172 delta = ddpa->cloneusedsnap -
2173 dd->dd_phys->dd_used_breakdown[DD_USED_SNAP];
2174 ASSERT3S(delta, >=, 0);
2175 ASSERT3U(ddpa->used, >=, delta);
2176 dsl_dir_diduse_space(dd, DD_USED_SNAP, delta, 0, 0, tx);
2177 dsl_dir_diduse_space(dd, DD_USED_HEAD,
2178 ddpa->used - delta, ddpa->comp, ddpa->uncomp, tx);
2179
2180 delta = ddpa->originusedsnap -
2181 odd->dd_phys->dd_used_breakdown[DD_USED_SNAP];
2182 ASSERT3S(delta, <=, 0);
2183 ASSERT3U(ddpa->used, >=, -delta);
2184 dsl_dir_diduse_space(odd, DD_USED_SNAP, delta, 0, 0, tx);
2185 dsl_dir_diduse_space(odd, DD_USED_HEAD,
2186 -ddpa->used - delta, -ddpa->comp, -ddpa->uncomp, tx);
2187
2188 origin_ds->ds_phys->ds_unique_bytes = ddpa->unique;
2189
2190 /* log history record */
2191 spa_history_log_internal_ds(hds, "promote", tx, "");
2192
2193 dsl_dir_rele(odd, FTAG);
2194 promote_rele(ddpa, FTAG);
2195 }
2196
2197 /*
2198 * Make a list of dsl_dataset_t's for the snapshots between first_obj
2199 * (exclusive) and last_obj (inclusive). The list will be in reverse
2200 * order (last_obj will be the list_head()). If first_obj == 0, do all
2201 * snapshots back to this dataset's origin.
2202 */
2203 static int
2204 snaplist_make(dsl_pool_t *dp,
2205 uint64_t first_obj, uint64_t last_obj, list_t *l, void *tag)
2206 {
2207 uint64_t obj = last_obj;
2208
2209 list_create(l, sizeof (struct promotenode),
2210 offsetof(struct promotenode, link));
2211
2212 while (obj != first_obj) {
2213 dsl_dataset_t *ds;
2214 struct promotenode *snap;
2215 int err;
2216
2217 err = dsl_dataset_hold_obj(dp, obj, tag, &ds);
2218 ASSERT(err != ENOENT);
2219 if (err != 0)
2220 return (err);
2221
2222 if (first_obj == 0)
2223 first_obj = ds->ds_dir->dd_phys->dd_origin_obj;
2224
2225 snap = kmem_alloc(sizeof (*snap), KM_SLEEP);
2226 snap->ds = ds;
2227 list_insert_tail(l, snap);
2228 obj = ds->ds_phys->ds_prev_snap_obj;
2229 }
2230
2231 return (0);
2232 }
2233
2234 static int
2235 snaplist_space(list_t *l, uint64_t mintxg, uint64_t *spacep)
2236 {
2237 struct promotenode *snap;
2238
2239 *spacep = 0;
2240 for (snap = list_head(l); snap; snap = list_next(l, snap)) {
2241 uint64_t used, comp, uncomp;
2242 dsl_deadlist_space_range(&snap->ds->ds_deadlist,
2243 mintxg, UINT64_MAX, &used, &comp, &uncomp);
2244 *spacep += used;
2245 }
2246 return (0);
2247 }
2248
2249 static void
2250 snaplist_destroy(list_t *l, void *tag)
2251 {
2252 struct promotenode *snap;
2253
2254 if (l == NULL || !list_link_active(&l->list_head))
2255 return;
2256
2257 while ((snap = list_tail(l)) != NULL) {
2258 list_remove(l, snap);
2259 dsl_dataset_rele(snap->ds, tag);
2260 kmem_free(snap, sizeof (*snap));
2261 }
2262 list_destroy(l);
2263 }
2264
2265 static int
2266 promote_hold(dsl_dataset_promote_arg_t *ddpa, dsl_pool_t *dp, void *tag)
2267 {
2268 int error;
2269 dsl_dir_t *dd;
2270 struct promotenode *snap;
2271
2272 error = dsl_dataset_hold(dp, ddpa->ddpa_clonename, tag,
2273 &ddpa->ddpa_clone);
2274 if (error != 0)
2275 return (error);
2276 dd = ddpa->ddpa_clone->ds_dir;
2277
2278 if (dsl_dataset_is_snapshot(ddpa->ddpa_clone) ||
2279 !dsl_dir_is_clone(dd)) {
2280 dsl_dataset_rele(ddpa->ddpa_clone, tag);
2281 return (SET_ERROR(EINVAL));
2282 }
2283
2284 error = snaplist_make(dp, 0, dd->dd_phys->dd_origin_obj,
2285 &ddpa->shared_snaps, tag);
2286 if (error != 0)
2287 goto out;
2288
2289 error = snaplist_make(dp, 0, ddpa->ddpa_clone->ds_object,
2290 &ddpa->clone_snaps, tag);
2291 if (error != 0)
2292 goto out;
2293
2294 snap = list_head(&ddpa->shared_snaps);
2295 ASSERT3U(snap->ds->ds_object, ==, dd->dd_phys->dd_origin_obj);
2296 error = snaplist_make(dp, dd->dd_phys->dd_origin_obj,
2297 snap->ds->ds_dir->dd_phys->dd_head_dataset_obj,
2298 &ddpa->origin_snaps, tag);
2299 if (error != 0)
2300 goto out;
2301
2302 if (snap->ds->ds_dir->dd_phys->dd_origin_obj != 0) {
2303 error = dsl_dataset_hold_obj(dp,
2304 snap->ds->ds_dir->dd_phys->dd_origin_obj,
2305 tag, &ddpa->origin_origin);
2306 if (error != 0)
2307 goto out;
2308 }
2309 out:
2310 if (error != 0)
2311 promote_rele(ddpa, tag);
2312 return (error);
2313 }
2314
2315 static void
2316 promote_rele(dsl_dataset_promote_arg_t *ddpa, void *tag)
2317 {
2318 snaplist_destroy(&ddpa->shared_snaps, tag);
2319 snaplist_destroy(&ddpa->clone_snaps, tag);
2320 snaplist_destroy(&ddpa->origin_snaps, tag);
2321 if (ddpa->origin_origin != NULL)
2322 dsl_dataset_rele(ddpa->origin_origin, tag);
2323 dsl_dataset_rele(ddpa->ddpa_clone, tag);
2324 }
2325
2326 /*
2327 * Promote a clone.
2328 *
2329 * If it fails due to a conflicting snapshot name, "conflsnap" will be filled
2330 * in with the name. (It must be at least MAXNAMELEN bytes long.)
2331 */
2332 int
2333 dsl_dataset_promote(const char *name, char *conflsnap)
2334 {
2335 dsl_dataset_promote_arg_t ddpa = { 0 };
2336 uint64_t numsnaps;
2337 int error;
2338 objset_t *os;
2339
2340 /*
2341 * We will modify space proportional to the number of
2342 * snapshots. Compute numsnaps.
2343 */
2344 error = dmu_objset_hold(name, FTAG, &os);
2345 if (error != 0)
2346 return (error);
2347 error = zap_count(dmu_objset_pool(os)->dp_meta_objset,
2348 dmu_objset_ds(os)->ds_phys->ds_snapnames_zapobj, &numsnaps);
2349 dmu_objset_rele(os, FTAG);
2350 if (error != 0)
2351 return (error);
2352
2353 ddpa.ddpa_clonename = name;
2354 ddpa.err_ds = conflsnap;
2355
2356 return (dsl_sync_task(name, dsl_dataset_promote_check,
2357 dsl_dataset_promote_sync, &ddpa, 2 + numsnaps));
2358 }
2359
2360 int
2361 dsl_dataset_clone_swap_check_impl(dsl_dataset_t *clone,
2362 dsl_dataset_t *origin_head, boolean_t force, void *owner, dmu_tx_t *tx)
2363 {
2364 int64_t unused_refres_delta;
2365
2366 /* they should both be heads */
2367 if (dsl_dataset_is_snapshot(clone) ||
2368 dsl_dataset_is_snapshot(origin_head))
2369 return (SET_ERROR(EINVAL));
2370
2371 /* if we are not forcing, the branch point should be just before them */
2372 if (!force && clone->ds_prev != origin_head->ds_prev)
2373 return (SET_ERROR(EINVAL));
2374
2375 /* clone should be the clone (unless they are unrelated) */
2376 if (clone->ds_prev != NULL &&
2377 clone->ds_prev != clone->ds_dir->dd_pool->dp_origin_snap &&
2378 origin_head->ds_dir != clone->ds_prev->ds_dir)
2379 return (SET_ERROR(EINVAL));
2380
2381 /* the clone should be a child of the origin */
2382 if (clone->ds_dir->dd_parent != origin_head->ds_dir)
2383 return (SET_ERROR(EINVAL));
2384
2385 /* origin_head shouldn't be modified unless 'force' */
2386 if (!force &&
2387 dsl_dataset_modified_since_snap(origin_head, origin_head->ds_prev))
2388 return (SET_ERROR(ETXTBSY));
2389
2390 /* origin_head should have no long holds (e.g. is not mounted) */
2391 if (dsl_dataset_handoff_check(origin_head, owner, tx))
2392 return (SET_ERROR(EBUSY));
2393
2394 /* check amount of any unconsumed refreservation */
2395 unused_refres_delta =
2396 (int64_t)MIN(origin_head->ds_reserved,
2397 origin_head->ds_phys->ds_unique_bytes) -
2398 (int64_t)MIN(origin_head->ds_reserved,
2399 clone->ds_phys->ds_unique_bytes);
2400
2401 if (unused_refres_delta > 0 &&
2402 unused_refres_delta >
2403 dsl_dir_space_available(origin_head->ds_dir, NULL, 0, TRUE))
2404 return (SET_ERROR(ENOSPC));
2405
2406 /* clone can't be over the head's refquota */
2407 if (origin_head->ds_quota != 0 &&
2408 clone->ds_phys->ds_referenced_bytes > origin_head->ds_quota)
2409 return (SET_ERROR(EDQUOT));
2410
2411 return (0);
2412 }
2413
2414 void
2415 dsl_dataset_clone_swap_sync_impl(dsl_dataset_t *clone,
2416 dsl_dataset_t *origin_head, dmu_tx_t *tx)
2417 {
2418 dsl_pool_t *dp = dmu_tx_pool(tx);
2419 int64_t unused_refres_delta;
2420
2421 ASSERT(clone->ds_reserved == 0);
2422 ASSERT(origin_head->ds_quota == 0 ||
2423 clone->ds_phys->ds_unique_bytes <= origin_head->ds_quota);
2424 ASSERT3P(clone->ds_prev, ==, origin_head->ds_prev);
2425
2426 dmu_buf_will_dirty(clone->ds_dbuf, tx);
2427 dmu_buf_will_dirty(origin_head->ds_dbuf, tx);
2428
2429 if (clone->ds_objset != NULL) {
2430 dmu_objset_evict(clone->ds_objset);
2431 clone->ds_objset = NULL;
2432 }
2433
2434 if (origin_head->ds_objset != NULL) {
2435 dmu_objset_evict(origin_head->ds_objset);
2436 origin_head->ds_objset = NULL;
2437 }
2438
2439 unused_refres_delta =
2440 (int64_t)MIN(origin_head->ds_reserved,
2441 origin_head->ds_phys->ds_unique_bytes) -
2442 (int64_t)MIN(origin_head->ds_reserved,
2443 clone->ds_phys->ds_unique_bytes);
2444
2445 /*
2446 * Reset origin's unique bytes, if it exists.
2447 */
2448 if (clone->ds_prev) {
2449 dsl_dataset_t *origin = clone->ds_prev;
2450 uint64_t comp, uncomp;
2451
2452 dmu_buf_will_dirty(origin->ds_dbuf, tx);
2453 dsl_deadlist_space_range(&clone->ds_deadlist,
2454 origin->ds_phys->ds_prev_snap_txg, UINT64_MAX,
2455 &origin->ds_phys->ds_unique_bytes, &comp, &uncomp);
2456 }
2457
2458 /* swap blkptrs */
2459 {
2460 blkptr_t tmp;
2461 tmp = origin_head->ds_phys->ds_bp;
2462 origin_head->ds_phys->ds_bp = clone->ds_phys->ds_bp;
2463 clone->ds_phys->ds_bp = tmp;
2464 }
2465
2466 /* set dd_*_bytes */
2467 {
2468 int64_t dused, dcomp, duncomp;
2469 uint64_t cdl_used, cdl_comp, cdl_uncomp;
2470 uint64_t odl_used, odl_comp, odl_uncomp;
2471
2472 ASSERT3U(clone->ds_dir->dd_phys->
2473 dd_used_breakdown[DD_USED_SNAP], ==, 0);
2474
2475 dsl_deadlist_space(&clone->ds_deadlist,
2476 &cdl_used, &cdl_comp, &cdl_uncomp);
2477 dsl_deadlist_space(&origin_head->ds_deadlist,
2478 &odl_used, &odl_comp, &odl_uncomp);
2479
2480 dused = clone->ds_phys->ds_referenced_bytes + cdl_used -
2481 (origin_head->ds_phys->ds_referenced_bytes + odl_used);
2482 dcomp = clone->ds_phys->ds_compressed_bytes + cdl_comp -
2483 (origin_head->ds_phys->ds_compressed_bytes + odl_comp);
2484 duncomp = clone->ds_phys->ds_uncompressed_bytes +
2485 cdl_uncomp -
2486 (origin_head->ds_phys->ds_uncompressed_bytes + odl_uncomp);
2487
2488 dsl_dir_diduse_space(origin_head->ds_dir, DD_USED_HEAD,
2489 dused, dcomp, duncomp, tx);
2490 dsl_dir_diduse_space(clone->ds_dir, DD_USED_HEAD,
2491 -dused, -dcomp, -duncomp, tx);
2492
2493 /*
2494 * The difference in the space used by snapshots is the
2495 * difference in snapshot space due to the head's
2496 * deadlist (since that's the only thing that's
2497 * changing that affects the snapused).
2498 */
2499 dsl_deadlist_space_range(&clone->ds_deadlist,
2500 origin_head->ds_dir->dd_origin_txg, UINT64_MAX,
2501 &cdl_used, &cdl_comp, &cdl_uncomp);
2502 dsl_deadlist_space_range(&origin_head->ds_deadlist,
2503 origin_head->ds_dir->dd_origin_txg, UINT64_MAX,
2504 &odl_used, &odl_comp, &odl_uncomp);
2505 dsl_dir_transfer_space(origin_head->ds_dir, cdl_used - odl_used,
2506 DD_USED_HEAD, DD_USED_SNAP, tx);
2507 }
2508
2509 /* swap ds_*_bytes */
2510 SWITCH64(origin_head->ds_phys->ds_referenced_bytes,
2511 clone->ds_phys->ds_referenced_bytes);
2512 SWITCH64(origin_head->ds_phys->ds_compressed_bytes,
2513 clone->ds_phys->ds_compressed_bytes);
2514 SWITCH64(origin_head->ds_phys->ds_uncompressed_bytes,
2515 clone->ds_phys->ds_uncompressed_bytes);
2516 SWITCH64(origin_head->ds_phys->ds_unique_bytes,
2517 clone->ds_phys->ds_unique_bytes);
2518
2519 /* apply any parent delta for change in unconsumed refreservation */
2520 dsl_dir_diduse_space(origin_head->ds_dir, DD_USED_REFRSRV,
2521 unused_refres_delta, 0, 0, tx);
2522
2523 /*
2524 * Swap deadlists.
2525 */
2526 dsl_deadlist_close(&clone->ds_deadlist);
2527 dsl_deadlist_close(&origin_head->ds_deadlist);
2528 SWITCH64(origin_head->ds_phys->ds_deadlist_obj,
2529 clone->ds_phys->ds_deadlist_obj);
2530 dsl_deadlist_open(&clone->ds_deadlist, dp->dp_meta_objset,
2531 clone->ds_phys->ds_deadlist_obj);
2532 dsl_deadlist_open(&origin_head->ds_deadlist, dp->dp_meta_objset,
2533 origin_head->ds_phys->ds_deadlist_obj);
2534
2535 dsl_scan_ds_clone_swapped(origin_head, clone, tx);
2536
2537 spa_history_log_internal_ds(clone, "clone swap", tx,
2538 "parent=%s", origin_head->ds_dir->dd_myname);
2539 }
2540
2541 /*
2542 * Given a pool name and a dataset object number in that pool,
2543 * return the name of that dataset.
2544 */
2545 int
2546 dsl_dsobj_to_dsname(char *pname, uint64_t obj, char *buf)
2547 {
2548 dsl_pool_t *dp;
2549 dsl_dataset_t *ds;
2550 int error;
2551
2552 error = dsl_pool_hold(pname, FTAG, &dp);
2553 if (error != 0)
2554 return (error);
2555
2556 error = dsl_dataset_hold_obj(dp, obj, FTAG, &ds);
2557 if (error == 0) {
2558 dsl_dataset_name(ds, buf);
2559 dsl_dataset_rele(ds, FTAG);
2560 }
2561 dsl_pool_rele(dp, FTAG);
2562
2563 return (error);
2564 }
2565
2566 int
2567 dsl_dataset_check_quota(dsl_dataset_t *ds, boolean_t check_quota,
2568 uint64_t asize, uint64_t inflight, uint64_t *used, uint64_t *ref_rsrv)
2569 {
2570 int error = 0;
2571
2572 ASSERT3S(asize, >, 0);
2573
2574 /*
2575 * *ref_rsrv is the portion of asize that will come from any
2576 * unconsumed refreservation space.
2577 */
2578 *ref_rsrv = 0;
2579
2580 mutex_enter(&ds->ds_lock);
2581 /*
2582 * Make a space adjustment for reserved bytes.
2583 */
2584 if (ds->ds_reserved > ds->ds_phys->ds_unique_bytes) {
2585 ASSERT3U(*used, >=,
2586 ds->ds_reserved - ds->ds_phys->ds_unique_bytes);
2587 *used -= (ds->ds_reserved - ds->ds_phys->ds_unique_bytes);
2588 *ref_rsrv =
2589 asize - MIN(asize, parent_delta(ds, asize + inflight));
2590 }
2591
2592 if (!check_quota || ds->ds_quota == 0) {
2593 mutex_exit(&ds->ds_lock);
2594 return (0);
2595 }
2596 /*
2597 * If they are requesting more space, and our current estimate
2598 * is over quota, they get to try again unless the actual
2599 * on-disk is over quota and there are no pending changes (which
2600 * may free up space for us).
2601 */
2602 if (ds->ds_phys->ds_referenced_bytes + inflight >= ds->ds_quota) {
2603 if (inflight > 0 ||
2604 ds->ds_phys->ds_referenced_bytes < ds->ds_quota)
2605 error = SET_ERROR(ERESTART);
2606 else
2607 error = SET_ERROR(EDQUOT);
2608 }
2609 mutex_exit(&ds->ds_lock);
2610
2611 return (error);
2612 }
2613
2614 typedef struct dsl_dataset_set_qr_arg {
2615 const char *ddsqra_name;
2616 zprop_source_t ddsqra_source;
2617 uint64_t ddsqra_value;
2618 } dsl_dataset_set_qr_arg_t;
2619
2620
2621 /* ARGSUSED */
2622 static int
2623 dsl_dataset_set_refquota_check(void *arg, dmu_tx_t *tx)
2624 {
2625 dsl_dataset_set_qr_arg_t *ddsqra = arg;
2626 dsl_pool_t *dp = dmu_tx_pool(tx);
2627 dsl_dataset_t *ds;
2628 int error;
2629 uint64_t newval;
2630
2631 if (spa_version(dp->dp_spa) < SPA_VERSION_REFQUOTA)
2632 return (SET_ERROR(ENOTSUP));
2633
2634 error = dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds);
2635 if (error != 0)
2636 return (error);
2637
2638 if (dsl_dataset_is_snapshot(ds)) {
2639 dsl_dataset_rele(ds, FTAG);
2640 return (SET_ERROR(EINVAL));
2641 }
2642
2643 error = dsl_prop_predict(ds->ds_dir,
2644 zfs_prop_to_name(ZFS_PROP_REFQUOTA),
2645 ddsqra->ddsqra_source, ddsqra->ddsqra_value, &newval);
2646 if (error != 0) {
2647 dsl_dataset_rele(ds, FTAG);
2648 return (error);
2649 }
2650
2651 if (newval == 0) {
2652 dsl_dataset_rele(ds, FTAG);
2653 return (0);
2654 }
2655
2656 if (newval < ds->ds_phys->ds_referenced_bytes ||
2657 newval < ds->ds_reserved) {
2658 dsl_dataset_rele(ds, FTAG);
2659 return (SET_ERROR(ENOSPC));
2660 }
2661
2662 dsl_dataset_rele(ds, FTAG);
2663 return (0);
2664 }
2665
2666 static void
2667 dsl_dataset_set_refquota_sync(void *arg, dmu_tx_t *tx)
2668 {
2669 dsl_dataset_set_qr_arg_t *ddsqra = arg;
2670 dsl_pool_t *dp = dmu_tx_pool(tx);
2671 dsl_dataset_t *ds;
2672 uint64_t newval;
2673
2674 VERIFY0(dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds));
2675
2676 dsl_prop_set_sync_impl(ds,
2677 zfs_prop_to_name(ZFS_PROP_REFQUOTA),
2678 ddsqra->ddsqra_source, sizeof (ddsqra->ddsqra_value), 1,
2679 &ddsqra->ddsqra_value, tx);
2680
2681 VERIFY0(dsl_prop_get_int_ds(ds,
2682 zfs_prop_to_name(ZFS_PROP_REFQUOTA), &newval));
2683
2684 if (ds->ds_quota != newval) {
2685 dmu_buf_will_dirty(ds->ds_dbuf, tx);
2686 ds->ds_quota = newval;
2687 }
2688 dsl_dataset_rele(ds, FTAG);
2689 }
2690
2691 int
2692 dsl_dataset_set_refquota(const char *dsname, zprop_source_t source,
2693 uint64_t refquota)
2694 {
2695 dsl_dataset_set_qr_arg_t ddsqra;
2696
2697 ddsqra.ddsqra_name = dsname;
2698 ddsqra.ddsqra_source = source;
2699 ddsqra.ddsqra_value = refquota;
2700
2701 return (dsl_sync_task(dsname, dsl_dataset_set_refquota_check,
2702 dsl_dataset_set_refquota_sync, &ddsqra, 0));
2703 }
2704
2705 static int
2706 dsl_dataset_set_refreservation_check(void *arg, dmu_tx_t *tx)
2707 {
2708 dsl_dataset_set_qr_arg_t *ddsqra = arg;
2709 dsl_pool_t *dp = dmu_tx_pool(tx);
2710 dsl_dataset_t *ds;
2711 int error;
2712 uint64_t newval, unique;
2713
2714 if (spa_version(dp->dp_spa) < SPA_VERSION_REFRESERVATION)
2715 return (SET_ERROR(ENOTSUP));
2716
2717 error = dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds);
2718 if (error != 0)
2719 return (error);
2720
2721 if (dsl_dataset_is_snapshot(ds)) {
2722 dsl_dataset_rele(ds, FTAG);
2723 return (SET_ERROR(EINVAL));
2724 }
2725
2726 error = dsl_prop_predict(ds->ds_dir,
2727 zfs_prop_to_name(ZFS_PROP_REFRESERVATION),
2728 ddsqra->ddsqra_source, ddsqra->ddsqra_value, &newval);
2729 if (error != 0) {
2730 dsl_dataset_rele(ds, FTAG);
2731 return (error);
2732 }
2733
2734 /*
2735 * If we are doing the preliminary check in open context, the
2736 * space estimates may be inaccurate.
2737 */
2738 if (!dmu_tx_is_syncing(tx)) {
2739 dsl_dataset_rele(ds, FTAG);
2740 return (0);
2741 }
2742
2743 mutex_enter(&ds->ds_lock);
2744 if (!DS_UNIQUE_IS_ACCURATE(ds))
2745 dsl_dataset_recalc_head_uniq(ds);
2746 unique = ds->ds_phys->ds_unique_bytes;
2747 mutex_exit(&ds->ds_lock);
2748
2749 if (MAX(unique, newval) > MAX(unique, ds->ds_reserved)) {
2750 uint64_t delta = MAX(unique, newval) -
2751 MAX(unique, ds->ds_reserved);
2752
2753 if (delta >
2754 dsl_dir_space_available(ds->ds_dir, NULL, 0, B_TRUE) ||
2755 (ds->ds_quota > 0 && newval > ds->ds_quota)) {
2756 dsl_dataset_rele(ds, FTAG);
2757 return (SET_ERROR(ENOSPC));
2758 }
2759 }
2760
2761 dsl_dataset_rele(ds, FTAG);
2762 return (0);
2763 }
2764
2765 void
2766 dsl_dataset_set_refreservation_sync_impl(dsl_dataset_t *ds,
2767 zprop_source_t source, uint64_t value, dmu_tx_t *tx)
2768 {
2769 uint64_t newval;
2770 uint64_t unique;
2771 int64_t delta;
2772
2773 dsl_prop_set_sync_impl(ds, zfs_prop_to_name(ZFS_PROP_REFRESERVATION),
2774 source, sizeof (value), 1, &value, tx);
2775
2776 VERIFY0(dsl_prop_get_int_ds(ds,
2777 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), &newval));
2778
2779 dmu_buf_will_dirty(ds->ds_dbuf, tx);
2780 mutex_enter(&ds->ds_dir->dd_lock);
2781 mutex_enter(&ds->ds_lock);
2782 ASSERT(DS_UNIQUE_IS_ACCURATE(ds));
2783 unique = ds->ds_phys->ds_unique_bytes;
2784 delta = MAX(0, (int64_t)(newval - unique)) -
2785 MAX(0, (int64_t)(ds->ds_reserved - unique));
2786 ds->ds_reserved = newval;
2787 mutex_exit(&ds->ds_lock);
2788
2789 dsl_dir_diduse_space(ds->ds_dir, DD_USED_REFRSRV, delta, 0, 0, tx);
2790 mutex_exit(&ds->ds_dir->dd_lock);
2791 }
2792
2793 static void
2794 dsl_dataset_set_refreservation_sync(void *arg, dmu_tx_t *tx)
2795 {
2796 dsl_dataset_set_qr_arg_t *ddsqra = arg;
2797 dsl_pool_t *dp = dmu_tx_pool(tx);
2798 dsl_dataset_t *ds;
2799
2800 VERIFY0(dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds));
2801 dsl_dataset_set_refreservation_sync_impl(ds,
2802 ddsqra->ddsqra_source, ddsqra->ddsqra_value, tx);
2803 dsl_dataset_rele(ds, FTAG);
2804 }
2805
2806 int
2807 dsl_dataset_set_refreservation(const char *dsname, zprop_source_t source,
2808 uint64_t refreservation)
2809 {
2810 dsl_dataset_set_qr_arg_t ddsqra;
2811
2812 ddsqra.ddsqra_name = dsname;
2813 ddsqra.ddsqra_source = source;
2814 ddsqra.ddsqra_value = refreservation;
2815
2816 return (dsl_sync_task(dsname, dsl_dataset_set_refreservation_check,
2817 dsl_dataset_set_refreservation_sync, &ddsqra, 0));
2818 }
2819
2820 /*
2821 * Return (in *usedp) the amount of space written in new that is not
2822 * present in oldsnap. New may be a snapshot or the head. Old must be
2823 * a snapshot before new, in new's filesystem (or its origin). If not then
2824 * fail and return EINVAL.
2825 *
2826 * The written space is calculated by considering two components: First, we
2827 * ignore any freed space, and calculate the written as new's used space
2828 * minus old's used space. Next, we add in the amount of space that was freed
2829 * between the two snapshots, thus reducing new's used space relative to old's.
2830 * Specifically, this is the space that was born before old->ds_creation_txg,
2831 * and freed before new (ie. on new's deadlist or a previous deadlist).
2832 *
2833 * space freed [---------------------]
2834 * snapshots ---O-------O--------O-------O------
2835 * oldsnap new
2836 */
2837 int
2838 dsl_dataset_space_written(dsl_dataset_t *oldsnap, dsl_dataset_t *new,
2839 uint64_t *usedp, uint64_t *compp, uint64_t *uncompp)
2840 {
2841 int err = 0;
2842 uint64_t snapobj;
2843 dsl_pool_t *dp = new->ds_dir->dd_pool;
2844
2845 ASSERT(dsl_pool_config_held(dp));
2846
2847 *usedp = 0;
2848 *usedp += new->ds_phys->ds_referenced_bytes;
2849 *usedp -= oldsnap->ds_phys->ds_referenced_bytes;
2850
2851 *compp = 0;
2852 *compp += new->ds_phys->ds_compressed_bytes;
2853 *compp -= oldsnap->ds_phys->ds_compressed_bytes;
2854
2855 *uncompp = 0;
2856 *uncompp += new->ds_phys->ds_uncompressed_bytes;
2857 *uncompp -= oldsnap->ds_phys->ds_uncompressed_bytes;
2858
2859 snapobj = new->ds_object;
2860 while (snapobj != oldsnap->ds_object) {
2861 dsl_dataset_t *snap;
2862 uint64_t used, comp, uncomp;
2863
2864 if (snapobj == new->ds_object) {
2865 snap = new;
2866 } else {
2867 err = dsl_dataset_hold_obj(dp, snapobj, FTAG, &snap);
2868 if (err != 0)
2869 break;
2870 }
2871
2872 if (snap->ds_phys->ds_prev_snap_txg ==
2873 oldsnap->ds_phys->ds_creation_txg) {
2874 /*
2875 * The blocks in the deadlist can not be born after
2876 * ds_prev_snap_txg, so get the whole deadlist space,
2877 * which is more efficient (especially for old-format
2878 * deadlists). Unfortunately the deadlist code
2879 * doesn't have enough information to make this
2880 * optimization itself.
2881 */
2882 dsl_deadlist_space(&snap->ds_deadlist,
2883 &used, &comp, &uncomp);
2884 } else {
2885 dsl_deadlist_space_range(&snap->ds_deadlist,
2886 0, oldsnap->ds_phys->ds_creation_txg,
2887 &used, &comp, &uncomp);
2888 }
2889 *usedp += used;
2890 *compp += comp;
2891 *uncompp += uncomp;
2892
2893 /*
2894 * If we get to the beginning of the chain of snapshots
2895 * (ds_prev_snap_obj == 0) before oldsnap, then oldsnap
2896 * was not a snapshot of/before new.
2897 */
2898 snapobj = snap->ds_phys->ds_prev_snap_obj;
2899 if (snap != new)
2900 dsl_dataset_rele(snap, FTAG);
2901 if (snapobj == 0) {
2902 err = SET_ERROR(EINVAL);
2903 break;
2904 }
2905
2906 }
2907 return (err);
2908 }
2909
2910 /*
2911 * Return (in *usedp) the amount of space that will be reclaimed if firstsnap,
2912 * lastsnap, and all snapshots in between are deleted.
2913 *
2914 * blocks that would be freed [---------------------------]
2915 * snapshots ---O-------O--------O-------O--------O
2916 * firstsnap lastsnap
2917 *
2918 * This is the set of blocks that were born after the snap before firstsnap,
2919 * (birth > firstsnap->prev_snap_txg) and died before the snap after the
2920 * last snap (ie, is on lastsnap->ds_next->ds_deadlist or an earlier deadlist).
2921 * We calculate this by iterating over the relevant deadlists (from the snap
2922 * after lastsnap, backward to the snap after firstsnap), summing up the
2923 * space on the deadlist that was born after the snap before firstsnap.
2924 */
2925 int
2926 dsl_dataset_space_wouldfree(dsl_dataset_t *firstsnap,
2927 dsl_dataset_t *lastsnap,
2928 uint64_t *usedp, uint64_t *compp, uint64_t *uncompp)
2929 {
2930 int err = 0;
2931 uint64_t snapobj;
2932 dsl_pool_t *dp = firstsnap->ds_dir->dd_pool;
2933
2934 ASSERT(dsl_dataset_is_snapshot(firstsnap));
2935 ASSERT(dsl_dataset_is_snapshot(lastsnap));
2936
2937 /*
2938 * Check that the snapshots are in the same dsl_dir, and firstsnap
2939 * is before lastsnap.
2940 */
2941 if (firstsnap->ds_dir != lastsnap->ds_dir ||
2942 firstsnap->ds_phys->ds_creation_txg >
2943 lastsnap->ds_phys->ds_creation_txg)
2944 return (SET_ERROR(EINVAL));
2945
2946 *usedp = *compp = *uncompp = 0;
2947
2948 snapobj = lastsnap->ds_phys->ds_next_snap_obj;
2949 while (snapobj != firstsnap->ds_object) {
2950 dsl_dataset_t *ds;
2951 uint64_t used, comp, uncomp;
2952
2953 err = dsl_dataset_hold_obj(dp, snapobj, FTAG, &ds);
2954 if (err != 0)
2955 break;
2956
2957 dsl_deadlist_space_range(&ds->ds_deadlist,
2958 firstsnap->ds_phys->ds_prev_snap_txg, UINT64_MAX,
2959 &used, &comp, &uncomp);
2960 *usedp += used;
2961 *compp += comp;
2962 *uncompp += uncomp;
2963
2964 snapobj = ds->ds_phys->ds_prev_snap_obj;
2965 ASSERT3U(snapobj, !=, 0);
2966 dsl_dataset_rele(ds, FTAG);
2967 }
2968 return (err);
2969 }
2970
2971 /*
2972 * Return TRUE if 'earlier' is an earlier snapshot in 'later's timeline.
2973 * For example, they could both be snapshots of the same filesystem, and
2974 * 'earlier' is before 'later'. Or 'earlier' could be the origin of
2975 * 'later's filesystem. Or 'earlier' could be an older snapshot in the origin's
2976 * filesystem. Or 'earlier' could be the origin's origin.
2977 *
2978 * If non-zero, earlier_txg is used instead of earlier's ds_creation_txg.
2979 */
2980 boolean_t
2981 dsl_dataset_is_before(dsl_dataset_t *later, dsl_dataset_t *earlier,
2982 uint64_t earlier_txg)
2983 {
2984 dsl_pool_t *dp = later->ds_dir->dd_pool;
2985 int error;
2986 boolean_t ret;
2987
2988 ASSERT(dsl_pool_config_held(dp));
2989 ASSERT(dsl_dataset_is_snapshot(earlier) || earlier_txg != 0);
2990
2991 if (earlier_txg == 0)
2992 earlier_txg = earlier->ds_phys->ds_creation_txg;
2993
2994 if (dsl_dataset_is_snapshot(later) &&
2995 earlier_txg >= later->ds_phys->ds_creation_txg)
2996 return (B_FALSE);
2997
2998 if (later->ds_dir == earlier->ds_dir)
2999 return (B_TRUE);
3000 if (!dsl_dir_is_clone(later->ds_dir))
3001 return (B_FALSE);
3002
3003 if (later->ds_dir->dd_phys->dd_origin_obj == earlier->ds_object)
3004 return (B_TRUE);
3005 dsl_dataset_t *origin;
3006 error = dsl_dataset_hold_obj(dp,
3007 later->ds_dir->dd_phys->dd_origin_obj, FTAG, &origin);
3008 if (error != 0)
3009 return (B_FALSE);
3010 ret = dsl_dataset_is_before(origin, earlier, earlier_txg);
3011 dsl_dataset_rele(origin, FTAG);
3012 return (ret);
3013 }
3014
3015
3016 void
3017 dsl_dataset_zapify(dsl_dataset_t *ds, dmu_tx_t *tx)
3018 {
3019 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
3020 dmu_object_zapify(mos, ds->ds_object, DMU_OT_DSL_DATASET, tx);
3021 }