]> git.proxmox.com Git - mirror_zfs.git/blob - module/zfs/dsl_dataset.c
projects / mirror_zfs.git / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
Illumos #3598
[mirror_zfs.git] / module / zfs / dsl_dataset.c
1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21 /*
22 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
23 * Copyright (c) 2013 by Delphix. All rights reserved.
24 * Copyright (c) 2012, Joyent, Inc. All rights reserved.
25 */
26
27 #include <sys/dmu_objset.h>
28 #include <sys/dsl_dataset.h>
29 #include <sys/dsl_dir.h>
30 #include <sys/dsl_prop.h>
31 #include <sys/dsl_synctask.h>
32 #include <sys/dmu_traverse.h>
33 #include <sys/dmu_impl.h>
34 #include <sys/dmu_tx.h>
35 #include <sys/arc.h>
36 #include <sys/zio.h>
37 #include <sys/zap.h>
38 #include <sys/zfeature.h>
39 #include <sys/unique.h>
40 #include <sys/zfs_context.h>
41 #include <sys/zfs_ioctl.h>
42 #include <sys/spa.h>
43 #include <sys/zfs_znode.h>
44 #include <sys/zfs_onexit.h>
45 #include <sys/zvol.h>
46 #include <sys/dsl_scan.h>
47 #include <sys/dsl_deadlist.h>
48 #include <sys/dsl_destroy.h>
49 #include <sys/dsl_userhold.h>
50
51 #define SWITCH64(x, y) \
52 { \
53 uint64_t __tmp = (x); \
54 (x) = (y); \
55 (y) = __tmp; \
56 }
57
58 #define DS_REF_MAX (1ULL << 62)
59
60 #define DSL_DEADLIST_BLOCKSIZE SPA_MAXBLOCKSIZE
61
62 /*
63 * Figure out how much of this delta should be propogated to the dsl_dir
64 * layer. If there's a refreservation, that space has already been
65 * partially accounted for in our ancestors.
66 */
67 static int64_t
68 parent_delta(dsl_dataset_t *ds, int64_t delta)
69 {
70 uint64_t old_bytes, new_bytes;
71
72 if (ds->ds_reserved == 0)
73 return (delta);
74
75 old_bytes = MAX(ds->ds_phys->ds_unique_bytes, ds->ds_reserved);
76 new_bytes = MAX(ds->ds_phys->ds_unique_bytes + delta, ds->ds_reserved);
77
78 ASSERT3U(ABS((int64_t)(new_bytes - old_bytes)), <=, ABS(delta));
79 return (new_bytes - old_bytes);
80 }
81
82 void
83 dsl_dataset_block_born(dsl_dataset_t *ds, const blkptr_t *bp, dmu_tx_t *tx)
84 {
85 int used, compressed, uncompressed;
86 int64_t delta;
87
88 used = bp_get_dsize_sync(tx->tx_pool->dp_spa, bp);
89 compressed = BP_GET_PSIZE(bp);
90 uncompressed = BP_GET_UCSIZE(bp);
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 dmu_buf_will_dirty(ds->ds_dbuf, tx);
106
107 mutex_enter(&ds->ds_dir->dd_lock);
108 mutex_enter(&ds->ds_lock);
109 delta = parent_delta(ds, used);
110 ds->ds_phys->ds_referenced_bytes += used;
111 ds->ds_phys->ds_compressed_bytes += compressed;
112 ds->ds_phys->ds_uncompressed_bytes += uncompressed;
113 ds->ds_phys->ds_unique_bytes += used;
114 mutex_exit(&ds->ds_lock);
115 dsl_dir_diduse_space(ds->ds_dir, DD_USED_HEAD, delta,
116 compressed, uncompressed, tx);
117 dsl_dir_transfer_space(ds->ds_dir, used - delta,
118 DD_USED_REFRSRV, DD_USED_HEAD, tx);
119 mutex_exit(&ds->ds_dir->dd_lock);
120 }
121
122 int
123 dsl_dataset_block_kill(dsl_dataset_t *ds, const blkptr_t *bp, dmu_tx_t *tx,
124 boolean_t async)
125 {
126 int used, compressed, uncompressed;
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 used = bp_get_dsize_sync(tx->tx_pool->dp_spa, bp);
135 compressed = BP_GET_PSIZE(bp);
136 uncompressed = BP_GET_UCSIZE(bp);
137
138 ASSERT(used > 0);
139 if (ds == NULL) {
140 dsl_free(tx->tx_pool, tx->tx_txg, bp);
141 dsl_pool_mos_diduse_space(tx->tx_pool,
142 -used, -compressed, -uncompressed);
143 return (used);
144 }
145 ASSERT3P(tx->tx_pool, ==, ds->ds_dir->dd_pool);
146
147 ASSERT(!dsl_dataset_is_snapshot(ds));
148 dmu_buf_will_dirty(ds->ds_dbuf, tx);
149
150 if (bp->blk_birth > ds->ds_phys->ds_prev_snap_txg) {
151 int64_t delta;
152
153 dprintf_bp(bp, "freeing ds=%llu", ds->ds_object);
154 dsl_free(tx->tx_pool, tx->tx_txg, bp);
155
156 mutex_enter(&ds->ds_dir->dd_lock);
157 mutex_enter(&ds->ds_lock);
158 ASSERT(ds->ds_phys->ds_unique_bytes >= used ||
159 !DS_UNIQUE_IS_ACCURATE(ds));
160 delta = parent_delta(ds, -used);
161 ds->ds_phys->ds_unique_bytes -= used;
162 mutex_exit(&ds->ds_lock);
163 dsl_dir_diduse_space(ds->ds_dir, DD_USED_HEAD,
164 delta, -compressed, -uncompressed, tx);
165 dsl_dir_transfer_space(ds->ds_dir, -used - delta,
166 DD_USED_REFRSRV, DD_USED_HEAD, tx);
167 mutex_exit(&ds->ds_dir->dd_lock);
168 } else {
169 dprintf_bp(bp, "putting on dead list: %s", "");
170 if (async) {
171 /*
172 * We are here as part of zio's write done callback,
173 * which means we're a zio interrupt thread. We can't
174 * call dsl_deadlist_insert() now because it may block
175 * waiting for I/O. Instead, put bp on the deferred
176 * queue and let dsl_pool_sync() finish the job.
177 */
178 bplist_append(&ds->ds_pending_deadlist, bp);
179 } else {
180 dsl_deadlist_insert(&ds->ds_deadlist, bp, tx);
181 }
182 ASSERT3U(ds->ds_prev->ds_object, ==,
183 ds->ds_phys->ds_prev_snap_obj);
184 ASSERT(ds->ds_prev->ds_phys->ds_num_children > 0);
185 /* if (bp->blk_birth > prev prev snap txg) prev unique += bs */
186 if (ds->ds_prev->ds_phys->ds_next_snap_obj ==
187 ds->ds_object && bp->blk_birth >
188 ds->ds_prev->ds_phys->ds_prev_snap_txg) {
189 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx);
190 mutex_enter(&ds->ds_prev->ds_lock);
191 ds->ds_prev->ds_phys->ds_unique_bytes += used;
192 mutex_exit(&ds->ds_prev->ds_lock);
193 }
194 if (bp->blk_birth > ds->ds_dir->dd_origin_txg) {
195 dsl_dir_transfer_space(ds->ds_dir, used,
196 DD_USED_HEAD, DD_USED_SNAP, tx);
197 }
198 }
199 mutex_enter(&ds->ds_lock);
200 ASSERT3U(ds->ds_phys->ds_referenced_bytes, >=, used);
201 ds->ds_phys->ds_referenced_bytes -= used;
202 ASSERT3U(ds->ds_phys->ds_compressed_bytes, >=, compressed);
203 ds->ds_phys->ds_compressed_bytes -= compressed;
204 ASSERT3U(ds->ds_phys->ds_uncompressed_bytes, >=, uncompressed);
205 ds->ds_phys->ds_uncompressed_bytes -= uncompressed;
206 mutex_exit(&ds->ds_lock);
207
208 return (used);
209 }
210
211 uint64_t
212 dsl_dataset_prev_snap_txg(dsl_dataset_t *ds)
213 {
214 uint64_t trysnap = 0;
215
216 if (ds == NULL)
217 return (0);
218 /*
219 * The snapshot creation could fail, but that would cause an
220 * incorrect FALSE return, which would only result in an
221 * overestimation of the amount of space that an operation would
222 * consume, which is OK.
223 *
224 * There's also a small window where we could miss a pending
225 * snapshot, because we could set the sync task in the quiescing
226 * phase. So this should only be used as a guess.
227 */
228 if (ds->ds_trysnap_txg >
229 spa_last_synced_txg(ds->ds_dir->dd_pool->dp_spa))
230 trysnap = ds->ds_trysnap_txg;
231 return (MAX(ds->ds_phys->ds_prev_snap_txg, trysnap));
232 }
233
234 boolean_t
235 dsl_dataset_block_freeable(dsl_dataset_t *ds, const blkptr_t *bp,
236 uint64_t blk_birth)
237 {
238 if (blk_birth <= dsl_dataset_prev_snap_txg(ds))
239 return (B_FALSE);
240
241 ddt_prefetch(dsl_dataset_get_spa(ds), bp);
242
243 return (B_TRUE);
244 }
245
246 /* ARGSUSED */
247 static void
248 dsl_dataset_evict(dmu_buf_t *db, void *dsv)
249 {
250 dsl_dataset_t *ds = dsv;
251
252 ASSERT(ds->ds_owner == NULL);
253
254 unique_remove(ds->ds_fsid_guid);
255
256 if (ds->ds_objset != NULL)
257 dmu_objset_evict(ds->ds_objset);
258
259 if (ds->ds_prev) {
260 dsl_dataset_rele(ds->ds_prev, ds);
261 ds->ds_prev = NULL;
262 }
263
264 bplist_destroy(&ds->ds_pending_deadlist);
265 if (ds->ds_phys->ds_deadlist_obj != 0)
266 dsl_deadlist_close(&ds->ds_deadlist);
267 if (ds->ds_dir)
268 dsl_dir_rele(ds->ds_dir, ds);
269
270 ASSERT(!list_link_active(&ds->ds_synced_link));
271
272 mutex_destroy(&ds->ds_lock);
273 mutex_destroy(&ds->ds_opening_lock);
274 refcount_destroy(&ds->ds_longholds);
275
276 kmem_free(ds, sizeof (dsl_dataset_t));
277 }
278
279 int
280 dsl_dataset_get_snapname(dsl_dataset_t *ds)
281 {
282 dsl_dataset_phys_t *headphys;
283 int err;
284 dmu_buf_t *headdbuf;
285 dsl_pool_t *dp = ds->ds_dir->dd_pool;
286 objset_t *mos = dp->dp_meta_objset;
287
288 if (ds->ds_snapname[0])
289 return (0);
290 if (ds->ds_phys->ds_next_snap_obj == 0)
291 return (0);
292
293 err = dmu_bonus_hold(mos, ds->ds_dir->dd_phys->dd_head_dataset_obj,
294 FTAG, &headdbuf);
295 if (err != 0)
296 return (err);
297 headphys = headdbuf->db_data;
298 err = zap_value_search(dp->dp_meta_objset,
299 headphys->ds_snapnames_zapobj, ds->ds_object, 0, ds->ds_snapname);
300 dmu_buf_rele(headdbuf, FTAG);
301 return (err);
302 }
303
304 int
305 dsl_dataset_snap_lookup(dsl_dataset_t *ds, const char *name, uint64_t *value)
306 {
307 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
308 uint64_t snapobj = ds->ds_phys->ds_snapnames_zapobj;
309 matchtype_t mt;
310 int err;
311
312 if (ds->ds_phys->ds_flags & DS_FLAG_CI_DATASET)
313 mt = MT_FIRST;
314 else
315 mt = MT_EXACT;
316
317 err = zap_lookup_norm(mos, snapobj, name, 8, 1,
318 value, mt, NULL, 0, NULL);
319 if (err == ENOTSUP && mt == MT_FIRST)
320 err = zap_lookup(mos, snapobj, name, 8, 1, value);
321 return (err);
322 }
323
324 int
325 dsl_dataset_snap_remove(dsl_dataset_t *ds, const char *name, dmu_tx_t *tx)
326 {
327 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
328 uint64_t snapobj = ds->ds_phys->ds_snapnames_zapobj;
329 matchtype_t mt;
330 int err;
331
332 dsl_dir_snap_cmtime_update(ds->ds_dir);
333
334 if (ds->ds_phys->ds_flags & DS_FLAG_CI_DATASET)
335 mt = MT_FIRST;
336 else
337 mt = MT_EXACT;
338
339 err = zap_remove_norm(mos, snapobj, name, mt, tx);
340 if (err == ENOTSUP && mt == MT_FIRST)
341 err = zap_remove(mos, snapobj, name, tx);
342 return (err);
343 }
344
345 int
346 dsl_dataset_hold_obj(dsl_pool_t *dp, uint64_t dsobj, void *tag,
347 dsl_dataset_t **dsp)
348 {
349 objset_t *mos = dp->dp_meta_objset;
350 dmu_buf_t *dbuf;
351 dsl_dataset_t *ds;
352 int err;
353 dmu_object_info_t doi;
354
355 ASSERT(dsl_pool_config_held(dp));
356
357 err = dmu_bonus_hold(mos, dsobj, tag, &dbuf);
358 if (err != 0)
359 return (err);
360
361 /* Make sure dsobj has the correct object type. */
362 dmu_object_info_from_db(dbuf, &doi);
363 if (doi.doi_type != DMU_OT_DSL_DATASET)
364 return (SET_ERROR(EINVAL));
365
366 ds = dmu_buf_get_user(dbuf);
367 if (ds == NULL) {
368 dsl_dataset_t *winner = NULL;
369
370 ds = kmem_zalloc(sizeof (dsl_dataset_t), KM_PUSHPAGE);
371 ds->ds_dbuf = dbuf;
372 ds->ds_object = dsobj;
373 ds->ds_phys = dbuf->db_data;
374 list_link_init(&ds->ds_synced_link);
375
376 mutex_init(&ds->ds_lock, NULL, MUTEX_DEFAULT, NULL);
377 mutex_init(&ds->ds_opening_lock, NULL, MUTEX_DEFAULT, NULL);
378 mutex_init(&ds->ds_sendstream_lock, NULL, MUTEX_DEFAULT, NULL);
379 refcount_create(&ds->ds_longholds);
380
381 bplist_create(&ds->ds_pending_deadlist);
382 dsl_deadlist_open(&ds->ds_deadlist,
383 mos, ds->ds_phys->ds_deadlist_obj);
384
385 list_create(&ds->ds_sendstreams, sizeof (dmu_sendarg_t),
386 offsetof(dmu_sendarg_t, dsa_link));
387
388 if (err == 0) {
389 err = dsl_dir_hold_obj(dp,
390 ds->ds_phys->ds_dir_obj, NULL, ds, &ds->ds_dir);
391 }
392 if (err != 0) {
393 mutex_destroy(&ds->ds_lock);
394 mutex_destroy(&ds->ds_opening_lock);
395 refcount_destroy(&ds->ds_longholds);
396 bplist_destroy(&ds->ds_pending_deadlist);
397 dsl_deadlist_close(&ds->ds_deadlist);
398 kmem_free(ds, sizeof (dsl_dataset_t));
399 dmu_buf_rele(dbuf, tag);
400 return (err);
401 }
402
403 if (!dsl_dataset_is_snapshot(ds)) {
404 ds->ds_snapname[0] = '\0';
405 if (ds->ds_phys->ds_prev_snap_obj != 0) {
406 err = dsl_dataset_hold_obj(dp,
407 ds->ds_phys->ds_prev_snap_obj,
408 ds, &ds->ds_prev);
409 }
410 } else {
411 if (zfs_flags & ZFS_DEBUG_SNAPNAMES)
412 err = dsl_dataset_get_snapname(ds);
413 if (err == 0 && ds->ds_phys->ds_userrefs_obj != 0) {
414 err = zap_count(
415 ds->ds_dir->dd_pool->dp_meta_objset,
416 ds->ds_phys->ds_userrefs_obj,
417 &ds->ds_userrefs);
418 }
419 }
420
421 if (err == 0 && !dsl_dataset_is_snapshot(ds)) {
422 err = dsl_prop_get_int_ds(ds,
423 zfs_prop_to_name(ZFS_PROP_REFRESERVATION),
424 &ds->ds_reserved);
425 if (err == 0) {
426 err = dsl_prop_get_int_ds(ds,
427 zfs_prop_to_name(ZFS_PROP_REFQUOTA),
428 &ds->ds_quota);
429 }
430 } else {
431 ds->ds_reserved = ds->ds_quota = 0;
432 }
433
434 if (err != 0 || (winner = dmu_buf_set_user_ie(dbuf, ds,
435 &ds->ds_phys, dsl_dataset_evict)) != NULL) {
436 bplist_destroy(&ds->ds_pending_deadlist);
437 dsl_deadlist_close(&ds->ds_deadlist);
438 if (ds->ds_prev)
439 dsl_dataset_rele(ds->ds_prev, ds);
440 dsl_dir_rele(ds->ds_dir, ds);
441 mutex_destroy(&ds->ds_lock);
442 mutex_destroy(&ds->ds_opening_lock);
443 refcount_destroy(&ds->ds_longholds);
444 kmem_free(ds, sizeof (dsl_dataset_t));
445 if (err != 0) {
446 dmu_buf_rele(dbuf, tag);
447 return (err);
448 }
449 ds = winner;
450 } else {
451 ds->ds_fsid_guid =
452 unique_insert(ds->ds_phys->ds_fsid_guid);
453 }
454 }
455 ASSERT3P(ds->ds_dbuf, ==, dbuf);
456 ASSERT3P(ds->ds_phys, ==, dbuf->db_data);
457 ASSERT(ds->ds_phys->ds_prev_snap_obj != 0 ||
458 spa_version(dp->dp_spa) < SPA_VERSION_ORIGIN ||
459 dp->dp_origin_snap == NULL || ds == dp->dp_origin_snap);
460 *dsp = ds;
461 return (0);
462 }
463
464 int
465 dsl_dataset_hold(dsl_pool_t *dp, const char *name,
466 void *tag, dsl_dataset_t **dsp)
467 {
468 dsl_dir_t *dd;
469 const char *snapname;
470 uint64_t obj;
471 int err = 0;
472
473 err = dsl_dir_hold(dp, name, FTAG, &dd, &snapname);
474 if (err != 0)
475 return (err);
476
477 ASSERT(dsl_pool_config_held(dp));
478 obj = dd->dd_phys->dd_head_dataset_obj;
479 if (obj != 0)
480 err = dsl_dataset_hold_obj(dp, obj, tag, dsp);
481 else
482 err = SET_ERROR(ENOENT);
483
484 /* we may be looking for a snapshot */
485 if (err == 0 && snapname != NULL) {
486 dsl_dataset_t *ds;
487
488 if (*snapname++ != '@') {
489 dsl_dataset_rele(*dsp, tag);
490 dsl_dir_rele(dd, FTAG);
491 return (SET_ERROR(ENOENT));
492 }
493
494 dprintf("looking for snapshot '%s'\n", snapname);
495 err = dsl_dataset_snap_lookup(*dsp, snapname, &obj);
496 if (err == 0)
497 err = dsl_dataset_hold_obj(dp, obj, tag, &ds);
498 dsl_dataset_rele(*dsp, tag);
499
500 if (err == 0) {
501 mutex_enter(&ds->ds_lock);
502 if (ds->ds_snapname[0] == 0)
503 (void) strlcpy(ds->ds_snapname, snapname,
504 sizeof (ds->ds_snapname));
505 mutex_exit(&ds->ds_lock);
506 *dsp = ds;
507 }
508 }
509
510 dsl_dir_rele(dd, FTAG);
511 return (err);
512 }
513
514 int
515 dsl_dataset_own_obj(dsl_pool_t *dp, uint64_t dsobj,
516 void *tag, dsl_dataset_t **dsp)
517 {
518 int err = dsl_dataset_hold_obj(dp, dsobj, tag, dsp);
519 if (err != 0)
520 return (err);
521 if (!dsl_dataset_tryown(*dsp, tag)) {
522 dsl_dataset_rele(*dsp, tag);
523 *dsp = NULL;
524 return (SET_ERROR(EBUSY));
525 }
526 return (0);
527 }
528
529 int
530 dsl_dataset_own(dsl_pool_t *dp, const char *name,
531 void *tag, dsl_dataset_t **dsp)
532 {
533 int err = dsl_dataset_hold(dp, name, tag, dsp);
534 if (err != 0)
535 return (err);
536 if (!dsl_dataset_tryown(*dsp, tag)) {
537 dsl_dataset_rele(*dsp, tag);
538 return (SET_ERROR(EBUSY));
539 }
540 return (0);
541 }
542
543 /*
544 * See the comment above dsl_pool_hold() for details. In summary, a long
545 * hold is used to prevent destruction of a dataset while the pool hold
546 * is dropped, allowing other concurrent operations (e.g. spa_sync()).
547 *
548 * The dataset and pool must be held when this function is called. After it
549 * is called, the pool hold may be released while the dataset is still held
550 * and accessed.
551 */
552 void
553 dsl_dataset_long_hold(dsl_dataset_t *ds, void *tag)
554 {
555 ASSERT(dsl_pool_config_held(ds->ds_dir->dd_pool));
556 (void) refcount_add(&ds->ds_longholds, tag);
557 }
558
559 void
560 dsl_dataset_long_rele(dsl_dataset_t *ds, void *tag)
561 {
562 (void) refcount_remove(&ds->ds_longholds, tag);
563 }
564
565 /* Return B_TRUE if there are any long holds on this dataset. */
566 boolean_t
567 dsl_dataset_long_held(dsl_dataset_t *ds)
568 {
569 return (!refcount_is_zero(&ds->ds_longholds));
570 }
571
572 void
573 dsl_dataset_name(dsl_dataset_t *ds, char *name)
574 {
575 if (ds == NULL) {
576 (void) strcpy(name, "mos");
577 } else {
578 dsl_dir_name(ds->ds_dir, name);
579 VERIFY0(dsl_dataset_get_snapname(ds));
580 if (ds->ds_snapname[0]) {
581 (void) strcat(name, "@");
582 /*
583 * We use a "recursive" mutex so that we
584 * can call dprintf_ds() with ds_lock held.
585 */
586 if (!MUTEX_HELD(&ds->ds_lock)) {
587 mutex_enter(&ds->ds_lock);
588 (void) strcat(name, ds->ds_snapname);
589 mutex_exit(&ds->ds_lock);
590 } else {
591 (void) strcat(name, ds->ds_snapname);
592 }
593 }
594 }
595 }
596
597 void
598 dsl_dataset_rele(dsl_dataset_t *ds, void *tag)
599 {
600 dmu_buf_rele(ds->ds_dbuf, tag);
601 }
602
603 void
604 dsl_dataset_disown(dsl_dataset_t *ds, void *tag)
605 {
606 ASSERT(ds->ds_owner == tag && ds->ds_dbuf != NULL);
607
608 mutex_enter(&ds->ds_lock);
609 ds->ds_owner = NULL;
610 mutex_exit(&ds->ds_lock);
611 dsl_dataset_long_rele(ds, tag);
612 if (ds->ds_dbuf != NULL)
613 dsl_dataset_rele(ds, tag);
614 else
615 dsl_dataset_evict(NULL, ds);
616 }
617
618 boolean_t
619 dsl_dataset_tryown(dsl_dataset_t *ds, void *tag)
620 {
621 boolean_t gotit = FALSE;
622
623 mutex_enter(&ds->ds_lock);
624 if (ds->ds_owner == NULL && !DS_IS_INCONSISTENT(ds)) {
625 ds->ds_owner = tag;
626 dsl_dataset_long_hold(ds, tag);
627 gotit = TRUE;
628 }
629 mutex_exit(&ds->ds_lock);
630 return (gotit);
631 }
632
633 uint64_t
634 dsl_dataset_create_sync_dd(dsl_dir_t *dd, dsl_dataset_t *origin,
635 uint64_t flags, dmu_tx_t *tx)
636 {
637 dsl_pool_t *dp = dd->dd_pool;
638 dmu_buf_t *dbuf;
639 dsl_dataset_phys_t *dsphys;
640 uint64_t dsobj;
641 objset_t *mos = dp->dp_meta_objset;
642
643 if (origin == NULL)
644 origin = dp->dp_origin_snap;
645
646 ASSERT(origin == NULL || origin->ds_dir->dd_pool == dp);
647 ASSERT(origin == NULL || origin->ds_phys->ds_num_children > 0);
648 ASSERT(dmu_tx_is_syncing(tx));
649 ASSERT(dd->dd_phys->dd_head_dataset_obj == 0);
650
651 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0,
652 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx);
653 VERIFY0(dmu_bonus_hold(mos, dsobj, FTAG, &dbuf));
654 dmu_buf_will_dirty(dbuf, tx);
655 dsphys = dbuf->db_data;
656 bzero(dsphys, sizeof (dsl_dataset_phys_t));
657 dsphys->ds_dir_obj = dd->dd_object;
658 dsphys->ds_flags = flags;
659 dsphys->ds_fsid_guid = unique_create();
660 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid,
661 sizeof (dsphys->ds_guid));
662 dsphys->ds_snapnames_zapobj =
663 zap_create_norm(mos, U8_TEXTPREP_TOUPPER, DMU_OT_DSL_DS_SNAP_MAP,
664 DMU_OT_NONE, 0, tx);
665 dsphys->ds_creation_time = gethrestime_sec();
666 dsphys->ds_creation_txg = tx->tx_txg == TXG_INITIAL ? 1 : tx->tx_txg;
667
668 if (origin == NULL) {
669 dsphys->ds_deadlist_obj = dsl_deadlist_alloc(mos, tx);
670 } else {
671 dsl_dataset_t *ohds; /* head of the origin snapshot */
672
673 dsphys->ds_prev_snap_obj = origin->ds_object;
674 dsphys->ds_prev_snap_txg =
675 origin->ds_phys->ds_creation_txg;
676 dsphys->ds_referenced_bytes =
677 origin->ds_phys->ds_referenced_bytes;
678 dsphys->ds_compressed_bytes =
679 origin->ds_phys->ds_compressed_bytes;
680 dsphys->ds_uncompressed_bytes =
681 origin->ds_phys->ds_uncompressed_bytes;
682 dsphys->ds_bp = origin->ds_phys->ds_bp;
683 dsphys->ds_flags |= origin->ds_phys->ds_flags;
684
685 dmu_buf_will_dirty(origin->ds_dbuf, tx);
686 origin->ds_phys->ds_num_children++;
687
688 VERIFY0(dsl_dataset_hold_obj(dp,
689 origin->ds_dir->dd_phys->dd_head_dataset_obj, FTAG, &ohds));
690 dsphys->ds_deadlist_obj = dsl_deadlist_clone(&ohds->ds_deadlist,
691 dsphys->ds_prev_snap_txg, dsphys->ds_prev_snap_obj, tx);
692 dsl_dataset_rele(ohds, FTAG);
693
694 if (spa_version(dp->dp_spa) >= SPA_VERSION_NEXT_CLONES) {
695 if (origin->ds_phys->ds_next_clones_obj == 0) {
696 origin->ds_phys->ds_next_clones_obj =
697 zap_create(mos,
698 DMU_OT_NEXT_CLONES, DMU_OT_NONE, 0, tx);
699 }
700 VERIFY0(zap_add_int(mos,
701 origin->ds_phys->ds_next_clones_obj, dsobj, tx));
702 }
703
704 dmu_buf_will_dirty(dd->dd_dbuf, tx);
705 dd->dd_phys->dd_origin_obj = origin->ds_object;
706 if (spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) {
707 if (origin->ds_dir->dd_phys->dd_clones == 0) {
708 dmu_buf_will_dirty(origin->ds_dir->dd_dbuf, tx);
709 origin->ds_dir->dd_phys->dd_clones =
710 zap_create(mos,
711 DMU_OT_DSL_CLONES, DMU_OT_NONE, 0, tx);
712 }
713 VERIFY0(zap_add_int(mos,
714 origin->ds_dir->dd_phys->dd_clones, dsobj, tx));
715 }
716 }
717
718 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE)
719 dsphys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE;
720
721 dmu_buf_rele(dbuf, FTAG);
722
723 dmu_buf_will_dirty(dd->dd_dbuf, tx);
724 dd->dd_phys->dd_head_dataset_obj = dsobj;
725
726 return (dsobj);
727 }
728
729 static void
730 dsl_dataset_zero_zil(dsl_dataset_t *ds, dmu_tx_t *tx)
731 {
732 objset_t *os;
733
734 VERIFY0(dmu_objset_from_ds(ds, &os));
735 bzero(&os->os_zil_header, sizeof (os->os_zil_header));
736 dsl_dataset_dirty(ds, tx);
737 }
738
739 uint64_t
740 dsl_dataset_create_sync(dsl_dir_t *pdd, const char *lastname,
741 dsl_dataset_t *origin, uint64_t flags, cred_t *cr, dmu_tx_t *tx)
742 {
743 dsl_pool_t *dp = pdd->dd_pool;
744 uint64_t dsobj, ddobj;
745 dsl_dir_t *dd;
746
747 ASSERT(dmu_tx_is_syncing(tx));
748 ASSERT(lastname[0] != '@');
749
750 ddobj = dsl_dir_create_sync(dp, pdd, lastname, tx);
751 VERIFY0(dsl_dir_hold_obj(dp, ddobj, lastname, FTAG, &dd));
752
753 dsobj = dsl_dataset_create_sync_dd(dd, origin,
754 flags & ~DS_CREATE_FLAG_NODIRTY, tx);
755
756 dsl_deleg_set_create_perms(dd, tx, cr);
757
758 dsl_dir_rele(dd, FTAG);
759
760 /*
761 * If we are creating a clone, make sure we zero out any stale
762 * data from the origin snapshots zil header.
763 */
764 if (origin != NULL && !(flags & DS_CREATE_FLAG_NODIRTY)) {
765 dsl_dataset_t *ds;
766
767 VERIFY0(dsl_dataset_hold_obj(dp, dsobj, FTAG, &ds));
768 dsl_dataset_zero_zil(ds, tx);
769 dsl_dataset_rele(ds, FTAG);
770 }
771
772 return (dsobj);
773 }
774
775 /*
776 * The unique space in the head dataset can be calculated by subtracting
777 * the space used in the most recent snapshot, that is still being used
778 * in this file system, from the space currently in use. To figure out
779 * the space in the most recent snapshot still in use, we need to take
780 * the total space used in the snapshot and subtract out the space that
781 * has been freed up since the snapshot was taken.
782 */
783 void
784 dsl_dataset_recalc_head_uniq(dsl_dataset_t *ds)
785 {
786 uint64_t mrs_used;
787 uint64_t dlused, dlcomp, dluncomp;
788
789 ASSERT(!dsl_dataset_is_snapshot(ds));
790
791 if (ds->ds_phys->ds_prev_snap_obj != 0)
792 mrs_used = ds->ds_prev->ds_phys->ds_referenced_bytes;
793 else
794 mrs_used = 0;
795
796 dsl_deadlist_space(&ds->ds_deadlist, &dlused, &dlcomp, &dluncomp);
797
798 ASSERT3U(dlused, <=, mrs_used);
799 ds->ds_phys->ds_unique_bytes =
800 ds->ds_phys->ds_referenced_bytes - (mrs_used - dlused);
801
802 if (spa_version(ds->ds_dir->dd_pool->dp_spa) >=
803 SPA_VERSION_UNIQUE_ACCURATE)
804 ds->ds_phys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE;
805 }
806
807 void
808 dsl_dataset_remove_from_next_clones(dsl_dataset_t *ds, uint64_t obj,
809 dmu_tx_t *tx)
810 {
811 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
812 int err;
813 ASSERTV(uint64_t count);
814
815 ASSERT(ds->ds_phys->ds_num_children >= 2);
816 err = zap_remove_int(mos, ds->ds_phys->ds_next_clones_obj, obj, tx);
817 /*
818 * The err should not be ENOENT, but a bug in a previous version
819 * of the code could cause upgrade_clones_cb() to not set
820 * ds_next_snap_obj when it should, leading to a missing entry.
821 * If we knew that the pool was created after
822 * SPA_VERSION_NEXT_CLONES, we could assert that it isn't
823 * ENOENT. However, at least we can check that we don't have
824 * too many entries in the next_clones_obj even after failing to
825 * remove this one.
826 */
827 if (err != ENOENT)
828 VERIFY0(err);
829 ASSERT0(zap_count(mos, ds->ds_phys->ds_next_clones_obj,
830 &count));
831 ASSERT3U(count, <=, ds->ds_phys->ds_num_children - 2);
832 }
833
834
835 blkptr_t *
836 dsl_dataset_get_blkptr(dsl_dataset_t *ds)
837 {
838 return (&ds->ds_phys->ds_bp);
839 }
840
841 void
842 dsl_dataset_set_blkptr(dsl_dataset_t *ds, blkptr_t *bp, dmu_tx_t *tx)
843 {
844 ASSERT(dmu_tx_is_syncing(tx));
845 /* If it's the meta-objset, set dp_meta_rootbp */
846 if (ds == NULL) {
847 tx->tx_pool->dp_meta_rootbp = *bp;
848 } else {
849 dmu_buf_will_dirty(ds->ds_dbuf, tx);
850 ds->ds_phys->ds_bp = *bp;
851 }
852 }
853
854 spa_t *
855 dsl_dataset_get_spa(dsl_dataset_t *ds)
856 {
857 return (ds->ds_dir->dd_pool->dp_spa);
858 }
859
860 void
861 dsl_dataset_dirty(dsl_dataset_t *ds, dmu_tx_t *tx)
862 {
863 dsl_pool_t *dp;
864
865 if (ds == NULL) /* this is the meta-objset */
866 return;
867
868 ASSERT(ds->ds_objset != NULL);
869
870 if (ds->ds_phys->ds_next_snap_obj != 0)
871 panic("dirtying snapshot!");
872
873 dp = ds->ds_dir->dd_pool;
874
875 if (txg_list_add(&dp->dp_dirty_datasets, ds, tx->tx_txg)) {
876 /* up the hold count until we can be written out */
877 dmu_buf_add_ref(ds->ds_dbuf, ds);
878 }
879 }
880
881 boolean_t
882 dsl_dataset_is_dirty(dsl_dataset_t *ds)
883 {
884 int t;
885
886 for (t = 0; t < TXG_SIZE; t++) {
887 if (txg_list_member(&ds->ds_dir->dd_pool->dp_dirty_datasets,
888 ds, t))
889 return (B_TRUE);
890 }
891 return (B_FALSE);
892 }
893
894 static int
895 dsl_dataset_snapshot_reserve_space(dsl_dataset_t *ds, dmu_tx_t *tx)
896 {
897 uint64_t asize;
898
899 if (!dmu_tx_is_syncing(tx))
900 return (0);
901
902 /*
903 * If there's an fs-only reservation, any blocks that might become
904 * owned by the snapshot dataset must be accommodated by space
905 * outside of the reservation.
906 */
907 ASSERT(ds->ds_reserved == 0 || DS_UNIQUE_IS_ACCURATE(ds));
908 asize = MIN(ds->ds_phys->ds_unique_bytes, ds->ds_reserved);
909 if (asize > dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE))
910 return (SET_ERROR(ENOSPC));
911
912 /*
913 * Propagate any reserved space for this snapshot to other
914 * snapshot checks in this sync group.
915 */
916 if (asize > 0)
917 dsl_dir_willuse_space(ds->ds_dir, asize, tx);
918
919 return (0);
920 }
921
922 typedef struct dsl_dataset_snapshot_arg {
923 nvlist_t *ddsa_snaps;
924 nvlist_t *ddsa_props;
925 nvlist_t *ddsa_errors;
926 } dsl_dataset_snapshot_arg_t;
927
928 int
929 dsl_dataset_snapshot_check_impl(dsl_dataset_t *ds, const char *snapname,
930 dmu_tx_t *tx)
931 {
932 int error;
933 uint64_t value;
934
935 ds->ds_trysnap_txg = tx->tx_txg;
936
937 if (!dmu_tx_is_syncing(tx))
938 return (0);
939
940 /*
941 * We don't allow multiple snapshots of the same txg. If there
942 * is already one, try again.
943 */
944 if (ds->ds_phys->ds_prev_snap_txg >= tx->tx_txg)
945 return (SET_ERROR(EAGAIN));
946
947 /*
948 * Check for conflicting snapshot name.
949 */
950 error = dsl_dataset_snap_lookup(ds, snapname, &value);
951 if (error == 0)
952 return (SET_ERROR(EEXIST));
953 if (error != ENOENT)
954 return (error);
955
956 error = dsl_dataset_snapshot_reserve_space(ds, tx);
957 if (error != 0)
958 return (error);
959
960 return (0);
961 }
962
963 static int
964 dsl_dataset_snapshot_check(void *arg, dmu_tx_t *tx)
965 {
966 dsl_dataset_snapshot_arg_t *ddsa = arg;
967 dsl_pool_t *dp = dmu_tx_pool(tx);
968 nvpair_t *pair;
969 int rv = 0;
970
971 for (pair = nvlist_next_nvpair(ddsa->ddsa_snaps, NULL);
972 pair != NULL; pair = nvlist_next_nvpair(ddsa->ddsa_snaps, pair)) {
973 int error = 0;
974 dsl_dataset_t *ds;
975 char *name, *atp;
976 char dsname[MAXNAMELEN];
977
978 name = nvpair_name(pair);
979 if (strlen(name) >= MAXNAMELEN)
980 error = SET_ERROR(ENAMETOOLONG);
981 if (error == 0) {
982 atp = strchr(name, '@');
983 if (atp == NULL)
984 error = SET_ERROR(EINVAL);
985 if (error == 0)
986 (void) strlcpy(dsname, name, atp - name + 1);
987 }
988 if (error == 0)
989 error = dsl_dataset_hold(dp, dsname, FTAG, &ds);
990 if (error == 0) {
991 error = dsl_dataset_snapshot_check_impl(ds,
992 atp + 1, tx);
993 dsl_dataset_rele(ds, FTAG);
994 }
995
996 if (error != 0) {
997 if (ddsa->ddsa_errors != NULL) {
998 fnvlist_add_int32(ddsa->ddsa_errors,
999 name, error);
1000 }
1001 rv = error;
1002 }
1003 }
1004 return (rv);
1005 }
1006
1007 void
1008 dsl_dataset_snapshot_sync_impl(dsl_dataset_t *ds, const char *snapname,
1009 dmu_tx_t *tx)
1010 {
1011 dsl_pool_t *dp = ds->ds_dir->dd_pool;
1012 dmu_buf_t *dbuf;
1013 dsl_dataset_phys_t *dsphys;
1014 uint64_t dsobj, crtxg;
1015 objset_t *mos = dp->dp_meta_objset;
1016 ASSERTV(static zil_header_t zero_zil);
1017 ASSERTV(objset_t *os);
1018
1019 ASSERT(RRW_WRITE_HELD(&dp->dp_config_rwlock));
1020
1021 /*
1022 * If we are on an old pool, the zil must not be active, in which
1023 * case it will be zeroed. Usually zil_suspend() accomplishes this.
1024 */
1025 ASSERT(spa_version(dmu_tx_pool(tx)->dp_spa) >= SPA_VERSION_FAST_SNAP ||
1026 dmu_objset_from_ds(ds, &os) != 0 ||
1027 bcmp(&os->os_phys->os_zil_header, &zero_zil,
1028 sizeof (zero_zil)) == 0);
1029
1030
1031 /*
1032 * The origin's ds_creation_txg has to be < TXG_INITIAL
1033 */
1034 if (strcmp(snapname, ORIGIN_DIR_NAME) == 0)
1035 crtxg = 1;
1036 else
1037 crtxg = tx->tx_txg;
1038
1039 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0,
1040 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx);
1041 VERIFY0(dmu_bonus_hold(mos, dsobj, FTAG, &dbuf));
1042 dmu_buf_will_dirty(dbuf, tx);
1043 dsphys = dbuf->db_data;
1044 bzero(dsphys, sizeof (dsl_dataset_phys_t));
1045 dsphys->ds_dir_obj = ds->ds_dir->dd_object;
1046 dsphys->ds_fsid_guid = unique_create();
1047 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid,
1048 sizeof (dsphys->ds_guid));
1049 dsphys->ds_prev_snap_obj = ds->ds_phys->ds_prev_snap_obj;
1050 dsphys->ds_prev_snap_txg = ds->ds_phys->ds_prev_snap_txg;
1051 dsphys->ds_next_snap_obj = ds->ds_object;
1052 dsphys->ds_num_children = 1;
1053 dsphys->ds_creation_time = gethrestime_sec();
1054 dsphys->ds_creation_txg = crtxg;
1055 dsphys->ds_deadlist_obj = ds->ds_phys->ds_deadlist_obj;
1056 dsphys->ds_referenced_bytes = ds->ds_phys->ds_referenced_bytes;
1057 dsphys->ds_compressed_bytes = ds->ds_phys->ds_compressed_bytes;
1058 dsphys->ds_uncompressed_bytes = ds->ds_phys->ds_uncompressed_bytes;
1059 dsphys->ds_flags = ds->ds_phys->ds_flags;
1060 dsphys->ds_bp = ds->ds_phys->ds_bp;
1061 dmu_buf_rele(dbuf, FTAG);
1062
1063 ASSERT3U(ds->ds_prev != 0, ==, ds->ds_phys->ds_prev_snap_obj != 0);
1064 if (ds->ds_prev) {
1065 uint64_t next_clones_obj =
1066 ds->ds_prev->ds_phys->ds_next_clones_obj;
1067 ASSERT(ds->ds_prev->ds_phys->ds_next_snap_obj ==
1068 ds->ds_object ||
1069 ds->ds_prev->ds_phys->ds_num_children > 1);
1070 if (ds->ds_prev->ds_phys->ds_next_snap_obj == ds->ds_object) {
1071 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx);
1072 ASSERT3U(ds->ds_phys->ds_prev_snap_txg, ==,
1073 ds->ds_prev->ds_phys->ds_creation_txg);
1074 ds->ds_prev->ds_phys->ds_next_snap_obj = dsobj;
1075 } else if (next_clones_obj != 0) {
1076 dsl_dataset_remove_from_next_clones(ds->ds_prev,
1077 dsphys->ds_next_snap_obj, tx);
1078 VERIFY0(zap_add_int(mos,
1079 next_clones_obj, dsobj, tx));
1080 }
1081 }
1082
1083 /*
1084 * If we have a reference-reservation on this dataset, we will
1085 * need to increase the amount of refreservation being charged
1086 * since our unique space is going to zero.
1087 */
1088 if (ds->ds_reserved) {
1089 int64_t delta;
1090 ASSERT(DS_UNIQUE_IS_ACCURATE(ds));
1091 delta = MIN(ds->ds_phys->ds_unique_bytes, ds->ds_reserved);
1092 dsl_dir_diduse_space(ds->ds_dir, DD_USED_REFRSRV,
1093 delta, 0, 0, tx);
1094 }
1095
1096 dmu_buf_will_dirty(ds->ds_dbuf, tx);
1097 ds->ds_phys->ds_deadlist_obj = dsl_deadlist_clone(&ds->ds_deadlist,
1098 UINT64_MAX, ds->ds_phys->ds_prev_snap_obj, tx);
1099 dsl_deadlist_close(&ds->ds_deadlist);
1100 dsl_deadlist_open(&ds->ds_deadlist, mos, ds->ds_phys->ds_deadlist_obj);
1101 dsl_deadlist_add_key(&ds->ds_deadlist,
1102 ds->ds_phys->ds_prev_snap_txg, tx);
1103
1104 ASSERT3U(ds->ds_phys->ds_prev_snap_txg, <, tx->tx_txg);
1105 ds->ds_phys->ds_prev_snap_obj = dsobj;
1106 ds->ds_phys->ds_prev_snap_txg = crtxg;
1107 ds->ds_phys->ds_unique_bytes = 0;
1108 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE)
1109 ds->ds_phys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE;
1110
1111 VERIFY0(zap_add(mos, ds->ds_phys->ds_snapnames_zapobj,
1112 snapname, 8, 1, &dsobj, tx));
1113
1114 if (ds->ds_prev)
1115 dsl_dataset_rele(ds->ds_prev, ds);
1116 VERIFY0(dsl_dataset_hold_obj(dp,
1117 ds->ds_phys->ds_prev_snap_obj, ds, &ds->ds_prev));
1118
1119 dsl_scan_ds_snapshotted(ds, tx);
1120
1121 dsl_dir_snap_cmtime_update(ds->ds_dir);
1122
1123 spa_history_log_internal_ds(ds->ds_prev, "snapshot", tx, "");
1124 }
1125
1126 static void
1127 dsl_dataset_snapshot_sync(void *arg, dmu_tx_t *tx)
1128 {
1129 dsl_dataset_snapshot_arg_t *ddsa = arg;
1130 dsl_pool_t *dp = dmu_tx_pool(tx);
1131 nvpair_t *pair;
1132
1133 for (pair = nvlist_next_nvpair(ddsa->ddsa_snaps, NULL);
1134 pair != NULL; pair = nvlist_next_nvpair(ddsa->ddsa_snaps, pair)) {
1135 dsl_dataset_t *ds;
1136 char *name, *atp;
1137 char dsname[MAXNAMELEN];
1138
1139 name = nvpair_name(pair);
1140 atp = strchr(name, '@');
1141 (void) strlcpy(dsname, name, atp - name + 1);
1142 VERIFY0(dsl_dataset_hold(dp, dsname, FTAG, &ds));
1143
1144 dsl_dataset_snapshot_sync_impl(ds, atp + 1, tx);
1145 if (ddsa->ddsa_props != NULL) {
1146 dsl_props_set_sync_impl(ds->ds_prev,
1147 ZPROP_SRC_LOCAL, ddsa->ddsa_props, tx);
1148 }
1149 dsl_dataset_rele(ds, FTAG);
1150 }
1151 }
1152
1153 /*
1154 * The snapshots must all be in the same pool.
1155 * All-or-nothing: if there are any failures, nothing will be modified.
1156 */
1157 int
1158 dsl_dataset_snapshot(nvlist_t *snaps, nvlist_t *props, nvlist_t *errors)
1159 {
1160 dsl_dataset_snapshot_arg_t ddsa;
1161 nvpair_t *pair;
1162 boolean_t needsuspend;
1163 int error;
1164 spa_t *spa;
1165 char *firstname;
1166 nvlist_t *suspended = NULL;
1167
1168 pair = nvlist_next_nvpair(snaps, NULL);
1169 if (pair == NULL)
1170 return (0);
1171 firstname = nvpair_name(pair);
1172
1173 error = spa_open(firstname, &spa, FTAG);
1174 if (error != 0)
1175 return (error);
1176 needsuspend = (spa_version(spa) < SPA_VERSION_FAST_SNAP);
1177 spa_close(spa, FTAG);
1178
1179 if (needsuspend) {
1180 suspended = fnvlist_alloc();
1181 for (pair = nvlist_next_nvpair(snaps, NULL); pair != NULL;
1182 pair = nvlist_next_nvpair(snaps, pair)) {
1183 char fsname[MAXNAMELEN];
1184 char *snapname = nvpair_name(pair);
1185 char *atp;
1186 void *cookie;
1187
1188 atp = strchr(snapname, '@');
1189 if (atp == NULL) {
1190 error = SET_ERROR(EINVAL);
1191 break;
1192 }
1193 (void) strlcpy(fsname, snapname, atp - snapname + 1);
1194
1195 error = zil_suspend(fsname, &cookie);
1196 if (error != 0)
1197 break;
1198 fnvlist_add_uint64(suspended, fsname,
1199 (uintptr_t)cookie);
1200 }
1201 }
1202
1203 ddsa.ddsa_snaps = snaps;
1204 ddsa.ddsa_props = props;
1205 ddsa.ddsa_errors = errors;
1206
1207 if (error == 0) {
1208 error = dsl_sync_task(firstname, dsl_dataset_snapshot_check,
1209 dsl_dataset_snapshot_sync, &ddsa,
1210 fnvlist_num_pairs(snaps) * 3);
1211 }
1212
1213 if (suspended != NULL) {
1214 for (pair = nvlist_next_nvpair(suspended, NULL); pair != NULL;
1215 pair = nvlist_next_nvpair(suspended, pair)) {
1216 zil_resume((void *)(uintptr_t)
1217 fnvpair_value_uint64(pair));
1218 }
1219 fnvlist_free(suspended);
1220 }
1221
1222 return (error);
1223 }
1224
1225 typedef struct dsl_dataset_snapshot_tmp_arg {
1226 const char *ddsta_fsname;
1227 const char *ddsta_snapname;
1228 minor_t ddsta_cleanup_minor;
1229 const char *ddsta_htag;
1230 } dsl_dataset_snapshot_tmp_arg_t;
1231
1232 static int
1233 dsl_dataset_snapshot_tmp_check(void *arg, dmu_tx_t *tx)
1234 {
1235 dsl_dataset_snapshot_tmp_arg_t *ddsta = arg;
1236 dsl_pool_t *dp = dmu_tx_pool(tx);
1237 dsl_dataset_t *ds;
1238 int error;
1239
1240 error = dsl_dataset_hold(dp, ddsta->ddsta_fsname, FTAG, &ds);
1241 if (error != 0)
1242 return (error);
1243
1244 error = dsl_dataset_snapshot_check_impl(ds, ddsta->ddsta_snapname, tx);
1245 if (error != 0) {
1246 dsl_dataset_rele(ds, FTAG);
1247 return (error);
1248 }
1249
1250 if (spa_version(dp->dp_spa) < SPA_VERSION_USERREFS) {
1251 dsl_dataset_rele(ds, FTAG);
1252 return (SET_ERROR(ENOTSUP));
1253 }
1254 error = dsl_dataset_user_hold_check_one(NULL, ddsta->ddsta_htag,
1255 B_TRUE, tx);
1256 if (error != 0) {
1257 dsl_dataset_rele(ds, FTAG);
1258 return (error);
1259 }
1260
1261 dsl_dataset_rele(ds, FTAG);
1262 return (0);
1263 }
1264
1265 static void
1266 dsl_dataset_snapshot_tmp_sync(void *arg, dmu_tx_t *tx)
1267 {
1268 dsl_dataset_snapshot_tmp_arg_t *ddsta = arg;
1269 dsl_pool_t *dp = dmu_tx_pool(tx);
1270 dsl_dataset_t *ds;
1271
1272 VERIFY0(dsl_dataset_hold(dp, ddsta->ddsta_fsname, FTAG, &ds));
1273
1274 dsl_dataset_snapshot_sync_impl(ds, ddsta->ddsta_snapname, tx);
1275 dsl_dataset_user_hold_sync_one(ds->ds_prev, ddsta->ddsta_htag,
1276 ddsta->ddsta_cleanup_minor, gethrestime_sec(), tx);
1277 dsl_destroy_snapshot_sync_impl(ds->ds_prev, B_TRUE, tx);
1278
1279 dsl_dataset_rele(ds, FTAG);
1280 }
1281
1282 int
1283 dsl_dataset_snapshot_tmp(const char *fsname, const char *snapname,
1284 minor_t cleanup_minor, const char *htag)
1285 {
1286 dsl_dataset_snapshot_tmp_arg_t ddsta;
1287 int error;
1288 spa_t *spa;
1289 boolean_t needsuspend;
1290 void *cookie;
1291
1292 ddsta.ddsta_fsname = fsname;
1293 ddsta.ddsta_snapname = snapname;
1294 ddsta.ddsta_cleanup_minor = cleanup_minor;
1295 ddsta.ddsta_htag = htag;
1296
1297 error = spa_open(fsname, &spa, FTAG);
1298 if (error != 0)
1299 return (error);
1300 needsuspend = (spa_version(spa) < SPA_VERSION_FAST_SNAP);
1301 spa_close(spa, FTAG);
1302
1303 if (needsuspend) {
1304 error = zil_suspend(fsname, &cookie);
1305 if (error != 0)
1306 return (error);
1307 }
1308
1309 error = dsl_sync_task(fsname, dsl_dataset_snapshot_tmp_check,
1310 dsl_dataset_snapshot_tmp_sync, &ddsta, 3);
1311
1312 if (needsuspend)
1313 zil_resume(cookie);
1314 return (error);
1315 }
1316
1317
1318 void
1319 dsl_dataset_sync(dsl_dataset_t *ds, zio_t *zio, dmu_tx_t *tx)
1320 {
1321 ASSERT(dmu_tx_is_syncing(tx));
1322 ASSERT(ds->ds_objset != NULL);
1323 ASSERT(ds->ds_phys->ds_next_snap_obj == 0);
1324
1325 /*
1326 * in case we had to change ds_fsid_guid when we opened it,
1327 * sync it out now.
1328 */
1329 dmu_buf_will_dirty(ds->ds_dbuf, tx);
1330 ds->ds_phys->ds_fsid_guid = ds->ds_fsid_guid;
1331
1332 dmu_objset_sync(ds->ds_objset, zio, tx);
1333 }
1334
1335 static void
1336 get_clones_stat(dsl_dataset_t *ds, nvlist_t *nv)
1337 {
1338 uint64_t count = 0;
1339 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
1340 zap_cursor_t zc;
1341 zap_attribute_t za;
1342 nvlist_t *propval = fnvlist_alloc();
1343 nvlist_t *val = fnvlist_alloc();
1344
1345 ASSERT(dsl_pool_config_held(ds->ds_dir->dd_pool));
1346
1347 /*
1348 * There may be missing entries in ds_next_clones_obj
1349 * due to a bug in a previous version of the code.
1350 * Only trust it if it has the right number of entries.
1351 */
1352 if (ds->ds_phys->ds_next_clones_obj != 0) {
1353 ASSERT0(zap_count(mos, ds->ds_phys->ds_next_clones_obj,
1354 &count));
1355 }
1356 if (count != ds->ds_phys->ds_num_children - 1)
1357 goto fail;
1358 for (zap_cursor_init(&zc, mos, ds->ds_phys->ds_next_clones_obj);
1359 zap_cursor_retrieve(&zc, &za) == 0;
1360 zap_cursor_advance(&zc)) {
1361 dsl_dataset_t *clone;
1362 char buf[ZFS_MAXNAMELEN];
1363 VERIFY0(dsl_dataset_hold_obj(ds->ds_dir->dd_pool,
1364 za.za_first_integer, FTAG, &clone));
1365 dsl_dir_name(clone->ds_dir, buf);
1366 fnvlist_add_boolean(val, buf);
1367 dsl_dataset_rele(clone, FTAG);
1368 }
1369 zap_cursor_fini(&zc);
1370 fnvlist_add_nvlist(propval, ZPROP_VALUE, val);
1371 fnvlist_add_nvlist(nv, zfs_prop_to_name(ZFS_PROP_CLONES), propval);
1372 fail:
1373 nvlist_free(val);
1374 nvlist_free(propval);
1375 }
1376
1377 void
1378 dsl_dataset_stats(dsl_dataset_t *ds, nvlist_t *nv)
1379 {
1380 uint64_t refd, avail, uobjs, aobjs, ratio;
1381 ASSERTV(dsl_pool_t *dp = ds->ds_dir->dd_pool);
1382
1383 ASSERT(dsl_pool_config_held(dp));
1384
1385 ratio = ds->ds_phys->ds_compressed_bytes == 0 ? 100 :
1386 (ds->ds_phys->ds_uncompressed_bytes * 100 /
1387 ds->ds_phys->ds_compressed_bytes);
1388
1389 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFRATIO, ratio);
1390 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_LOGICALREFERENCED,
1391 ds->ds_phys->ds_uncompressed_bytes);
1392
1393 if (dsl_dataset_is_snapshot(ds)) {
1394 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_COMPRESSRATIO, ratio);
1395 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USED,
1396 ds->ds_phys->ds_unique_bytes);
1397 get_clones_stat(ds, nv);
1398 } else {
1399 dsl_dir_stats(ds->ds_dir, nv);
1400 }
1401
1402 dsl_dataset_space(ds, &refd, &avail, &uobjs, &aobjs);
1403 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_AVAILABLE, avail);
1404 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFERENCED, refd);
1405
1406 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATION,
1407 ds->ds_phys->ds_creation_time);
1408 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATETXG,
1409 ds->ds_phys->ds_creation_txg);
1410 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFQUOTA,
1411 ds->ds_quota);
1412 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFRESERVATION,
1413 ds->ds_reserved);
1414 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_GUID,
1415 ds->ds_phys->ds_guid);
1416 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_UNIQUE,
1417 ds->ds_phys->ds_unique_bytes);
1418 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_OBJSETID,
1419 ds->ds_object);
1420 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USERREFS,
1421 ds->ds_userrefs);
1422 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_DEFER_DESTROY,
1423 DS_IS_DEFER_DESTROY(ds) ? 1 : 0);
1424
1425 if (ds->ds_phys->ds_prev_snap_obj != 0) {
1426 uint64_t written, comp, uncomp;
1427 dsl_pool_t *dp = ds->ds_dir->dd_pool;
1428 dsl_dataset_t *prev;
1429 int err;
1430
1431 err = dsl_dataset_hold_obj(dp,
1432 ds->ds_phys->ds_prev_snap_obj, FTAG, &prev);
1433 if (err == 0) {
1434 err = dsl_dataset_space_written(prev, ds, &written,
1435 &comp, &uncomp);
1436 dsl_dataset_rele(prev, FTAG);
1437 if (err == 0) {
1438 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_WRITTEN,
1439 written);
1440 }
1441 }
1442 }
1443
1444 }
1445
1446 void
1447 dsl_dataset_fast_stat(dsl_dataset_t *ds, dmu_objset_stats_t *stat)
1448 {
1449 dsl_pool_t *dp = ds->ds_dir->dd_pool;
1450 ASSERT(dsl_pool_config_held(dp));
1451
1452 stat->dds_creation_txg = ds->ds_phys->ds_creation_txg;
1453 stat->dds_inconsistent = ds->ds_phys->ds_flags & DS_FLAG_INCONSISTENT;
1454 stat->dds_guid = ds->ds_phys->ds_guid;
1455 stat->dds_origin[0] = '\0';
1456 if (dsl_dataset_is_snapshot(ds)) {
1457 stat->dds_is_snapshot = B_TRUE;
1458 stat->dds_num_clones = ds->ds_phys->ds_num_children - 1;
1459 } else {
1460 stat->dds_is_snapshot = B_FALSE;
1461 stat->dds_num_clones = 0;
1462
1463 if (dsl_dir_is_clone(ds->ds_dir)) {
1464 dsl_dataset_t *ods;
1465
1466 VERIFY0(dsl_dataset_hold_obj(dp,
1467 ds->ds_dir->dd_phys->dd_origin_obj, FTAG, &ods));
1468 dsl_dataset_name(ods, stat->dds_origin);
1469 dsl_dataset_rele(ods, FTAG);
1470 }
1471 }
1472 }
1473
1474 uint64_t
1475 dsl_dataset_fsid_guid(dsl_dataset_t *ds)
1476 {
1477 return (ds->ds_fsid_guid);
1478 }
1479
1480 void
1481 dsl_dataset_space(dsl_dataset_t *ds,
1482 uint64_t *refdbytesp, uint64_t *availbytesp,
1483 uint64_t *usedobjsp, uint64_t *availobjsp)
1484 {
1485 *refdbytesp = ds->ds_phys->ds_referenced_bytes;
1486 *availbytesp = dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE);
1487 if (ds->ds_reserved > ds->ds_phys->ds_unique_bytes)
1488 *availbytesp += ds->ds_reserved - ds->ds_phys->ds_unique_bytes;
1489 if (ds->ds_quota != 0) {
1490 /*
1491 * Adjust available bytes according to refquota
1492 */
1493 if (*refdbytesp < ds->ds_quota)
1494 *availbytesp = MIN(*availbytesp,
1495 ds->ds_quota - *refdbytesp);
1496 else
1497 *availbytesp = 0;
1498 }
1499 *usedobjsp = ds->ds_phys->ds_bp.blk_fill;
1500 *availobjsp = DN_MAX_OBJECT - *usedobjsp;
1501 }
1502
1503 boolean_t
1504 dsl_dataset_modified_since_lastsnap(dsl_dataset_t *ds)
1505 {
1506 ASSERTV(dsl_pool_t *dp = ds->ds_dir->dd_pool);
1507
1508 ASSERT(dsl_pool_config_held(dp));
1509 if (ds->ds_prev == NULL)
1510 return (B_FALSE);
1511 if (ds->ds_phys->ds_bp.blk_birth >
1512 ds->ds_prev->ds_phys->ds_creation_txg) {
1513 objset_t *os, *os_prev;
1514 /*
1515 * It may be that only the ZIL differs, because it was
1516 * reset in the head. Don't count that as being
1517 * modified.
1518 */
1519 if (dmu_objset_from_ds(ds, &os) != 0)
1520 return (B_TRUE);
1521 if (dmu_objset_from_ds(ds->ds_prev, &os_prev) != 0)
1522 return (B_TRUE);
1523 return (bcmp(&os->os_phys->os_meta_dnode,
1524 &os_prev->os_phys->os_meta_dnode,
1525 sizeof (os->os_phys->os_meta_dnode)) != 0);
1526 }
1527 return (B_FALSE);
1528 }
1529
1530 typedef struct dsl_dataset_rename_snapshot_arg {
1531 const char *ddrsa_fsname;
1532 const char *ddrsa_oldsnapname;
1533 const char *ddrsa_newsnapname;
1534 boolean_t ddrsa_recursive;
1535 dmu_tx_t *ddrsa_tx;
1536 } dsl_dataset_rename_snapshot_arg_t;
1537
1538 /* ARGSUSED */
1539 static int
1540 dsl_dataset_rename_snapshot_check_impl(dsl_pool_t *dp,
1541 dsl_dataset_t *hds, void *arg)
1542 {
1543 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg;
1544 int error;
1545 uint64_t val;
1546
1547 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_oldsnapname, &val);
1548 if (error != 0) {
1549 /* ignore nonexistent snapshots */
1550 return (error == ENOENT ? 0 : error);
1551 }
1552
1553 /* new name should not exist */
1554 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_newsnapname, &val);
1555 if (error == 0)
1556 error = SET_ERROR(EEXIST);
1557 else if (error == ENOENT)
1558 error = 0;
1559
1560 /* dataset name + 1 for the "@" + the new snapshot name must fit */
1561 if (dsl_dir_namelen(hds->ds_dir) + 1 +
1562 strlen(ddrsa->ddrsa_newsnapname) >= MAXNAMELEN)
1563 error = SET_ERROR(ENAMETOOLONG);
1564
1565 return (error);
1566 }
1567
1568 static int
1569 dsl_dataset_rename_snapshot_check(void *arg, dmu_tx_t *tx)
1570 {
1571 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg;
1572 dsl_pool_t *dp = dmu_tx_pool(tx);
1573 dsl_dataset_t *hds;
1574 int error;
1575
1576 error = dsl_dataset_hold(dp, ddrsa->ddrsa_fsname, FTAG, &hds);
1577 if (error != 0)
1578 return (error);
1579
1580 if (ddrsa->ddrsa_recursive) {
1581 error = dmu_objset_find_dp(dp, hds->ds_dir->dd_object,
1582 dsl_dataset_rename_snapshot_check_impl, ddrsa,
1583 DS_FIND_CHILDREN);
1584 } else {
1585 error = dsl_dataset_rename_snapshot_check_impl(dp, hds, ddrsa);
1586 }
1587 dsl_dataset_rele(hds, FTAG);
1588 return (error);
1589 }
1590
1591 static int
1592 dsl_dataset_rename_snapshot_sync_impl(dsl_pool_t *dp,
1593 dsl_dataset_t *hds, void *arg)
1594 {
1595 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg;
1596 dsl_dataset_t *ds;
1597 uint64_t val;
1598 dmu_tx_t *tx = ddrsa->ddrsa_tx;
1599 int error;
1600
1601 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_oldsnapname, &val);
1602 ASSERT(error == 0 || error == ENOENT);
1603 if (error == ENOENT) {
1604 /* ignore nonexistent snapshots */
1605 return (0);
1606 }
1607
1608 VERIFY0(dsl_dataset_hold_obj(dp, val, FTAG, &ds));
1609
1610 /* log before we change the name */
1611 spa_history_log_internal_ds(ds, "rename", tx,
1612 "-> @%s", ddrsa->ddrsa_newsnapname);
1613
1614 VERIFY0(dsl_dataset_snap_remove(hds, ddrsa->ddrsa_oldsnapname, tx));
1615 mutex_enter(&ds->ds_lock);
1616 (void) strcpy(ds->ds_snapname, ddrsa->ddrsa_newsnapname);
1617 mutex_exit(&ds->ds_lock);
1618 VERIFY0(zap_add(dp->dp_meta_objset, hds->ds_phys->ds_snapnames_zapobj,
1619 ds->ds_snapname, 8, 1, &ds->ds_object, tx));
1620
1621 dsl_dataset_rele(ds, FTAG);
1622 return (0);
1623 }
1624
1625 static void
1626 dsl_dataset_rename_snapshot_sync(void *arg, dmu_tx_t *tx)
1627 {
1628 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg;
1629 dsl_pool_t *dp = dmu_tx_pool(tx);
1630 dsl_dataset_t *hds;
1631
1632 VERIFY0(dsl_dataset_hold(dp, ddrsa->ddrsa_fsname, FTAG, &hds));
1633 ddrsa->ddrsa_tx = tx;
1634 if (ddrsa->ddrsa_recursive) {
1635 VERIFY0(dmu_objset_find_dp(dp, hds->ds_dir->dd_object,
1636 dsl_dataset_rename_snapshot_sync_impl, ddrsa,
1637 DS_FIND_CHILDREN));
1638 } else {
1639 VERIFY0(dsl_dataset_rename_snapshot_sync_impl(dp, hds, ddrsa));
1640 }
1641 dsl_dataset_rele(hds, FTAG);
1642 }
1643
1644 int
1645 dsl_dataset_rename_snapshot(const char *fsname,
1646 const char *oldsnapname, const char *newsnapname, boolean_t recursive)
1647 {
1648 dsl_dataset_rename_snapshot_arg_t ddrsa;
1649
1650 ddrsa.ddrsa_fsname = fsname;
1651 ddrsa.ddrsa_oldsnapname = oldsnapname;
1652 ddrsa.ddrsa_newsnapname = newsnapname;
1653 ddrsa.ddrsa_recursive = recursive;
1654
1655 return (dsl_sync_task(fsname, dsl_dataset_rename_snapshot_check,
1656 dsl_dataset_rename_snapshot_sync, &ddrsa, 1));
1657 }
1658
1659 static int
1660 dsl_dataset_rollback_check(void *arg, dmu_tx_t *tx)
1661 {
1662 const char *fsname = arg;
1663 dsl_pool_t *dp = dmu_tx_pool(tx);
1664 dsl_dataset_t *ds;
1665 int64_t unused_refres_delta;
1666 int error;
1667
1668 error = dsl_dataset_hold(dp, fsname, FTAG, &ds);
1669 if (error != 0)
1670 return (error);
1671
1672 /* must not be a snapshot */
1673 if (dsl_dataset_is_snapshot(ds)) {
1674 dsl_dataset_rele(ds, FTAG);
1675 return (SET_ERROR(EINVAL));
1676 }
1677
1678 /* must have a most recent snapshot */
1679 if (ds->ds_phys->ds_prev_snap_txg < TXG_INITIAL) {
1680 dsl_dataset_rele(ds, FTAG);
1681 return (SET_ERROR(EINVAL));
1682 }
1683
1684 if (dsl_dataset_long_held(ds)) {
1685 dsl_dataset_rele(ds, FTAG);
1686 return (SET_ERROR(EBUSY));
1687 }
1688
1689 /*
1690 * Check if the snap we are rolling back to uses more than
1691 * the refquota.
1692 */
1693 if (ds->ds_quota != 0 &&
1694 ds->ds_prev->ds_phys->ds_referenced_bytes > ds->ds_quota) {
1695 dsl_dataset_rele(ds, FTAG);
1696 return (SET_ERROR(EDQUOT));
1697 }
1698
1699 /*
1700 * When we do the clone swap, we will temporarily use more space
1701 * due to the refreservation (the head will no longer have any
1702 * unique space, so the entire amount of the refreservation will need
1703 * to be free). We will immediately destroy the clone, freeing
1704 * this space, but the freeing happens over many txg's.
1705 */
1706 unused_refres_delta = (int64_t)MIN(ds->ds_reserved,
1707 ds->ds_phys->ds_unique_bytes);
1708
1709 if (unused_refres_delta > 0 &&
1710 unused_refres_delta >
1711 dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE)) {
1712 dsl_dataset_rele(ds, FTAG);
1713 return (SET_ERROR(ENOSPC));
1714 }
1715
1716 dsl_dataset_rele(ds, FTAG);
1717 return (0);
1718 }
1719
1720 static void
1721 dsl_dataset_rollback_sync(void *arg, dmu_tx_t *tx)
1722 {
1723 const char *fsname = arg;
1724 dsl_pool_t *dp = dmu_tx_pool(tx);
1725 dsl_dataset_t *ds, *clone;
1726 uint64_t cloneobj;
1727
1728 VERIFY0(dsl_dataset_hold(dp, fsname, FTAG, &ds));
1729
1730 cloneobj = dsl_dataset_create_sync(ds->ds_dir, "%rollback",
1731 ds->ds_prev, DS_CREATE_FLAG_NODIRTY, kcred, tx);
1732
1733 VERIFY0(dsl_dataset_hold_obj(dp, cloneobj, FTAG, &clone));
1734
1735 dsl_dataset_clone_swap_sync_impl(clone, ds, tx);
1736 dsl_dataset_zero_zil(ds, tx);
1737
1738 dsl_destroy_head_sync_impl(clone, tx);
1739
1740 dsl_dataset_rele(clone, FTAG);
1741 dsl_dataset_rele(ds, FTAG);
1742 }
1743
1744 int
1745 dsl_dataset_rollback(const char *fsname)
1746 {
1747 return (dsl_sync_task(fsname, dsl_dataset_rollback_check,
1748 dsl_dataset_rollback_sync, (void *)fsname, 1));
1749 }
1750
1751 struct promotenode {
1752 list_node_t link;
1753 dsl_dataset_t *ds;
1754 };
1755
1756 typedef struct dsl_dataset_promote_arg {
1757 const char *ddpa_clonename;
1758 dsl_dataset_t *ddpa_clone;
1759 list_t shared_snaps, origin_snaps, clone_snaps;
1760 dsl_dataset_t *origin_origin; /* origin of the origin */
1761 uint64_t used, comp, uncomp, unique, cloneusedsnap, originusedsnap;
1762 char *err_ds;
1763 } dsl_dataset_promote_arg_t;
1764
1765 static int snaplist_space(list_t *l, uint64_t mintxg, uint64_t *spacep);
1766 static int promote_hold(dsl_dataset_promote_arg_t *ddpa, dsl_pool_t *dp,
1767 void *tag);
1768 static void promote_rele(dsl_dataset_promote_arg_t *ddpa, void *tag);
1769
1770 static int
1771 dsl_dataset_promote_check(void *arg, dmu_tx_t *tx)
1772 {
1773 dsl_dataset_promote_arg_t *ddpa = arg;
1774 dsl_pool_t *dp = dmu_tx_pool(tx);
1775 dsl_dataset_t *hds;
1776 struct promotenode *snap;
1777 dsl_dataset_t *origin_ds;
1778 int err;
1779 uint64_t unused;
1780
1781 err = promote_hold(ddpa, dp, FTAG);
1782 if (err != 0)
1783 return (err);
1784
1785 hds = ddpa->ddpa_clone;
1786
1787 if (hds->ds_phys->ds_flags & DS_FLAG_NOPROMOTE) {
1788 promote_rele(ddpa, FTAG);
1789 return (SET_ERROR(EXDEV));
1790 }
1791
1792 /*
1793 * Compute and check the amount of space to transfer. Since this is
1794 * so expensive, don't do the preliminary check.
1795 */
1796 if (!dmu_tx_is_syncing(tx)) {
1797 promote_rele(ddpa, FTAG);
1798 return (0);
1799 }
1800
1801 snap = list_head(&ddpa->shared_snaps);
1802 origin_ds = snap->ds;
1803
1804 /* compute origin's new unique space */
1805 snap = list_tail(&ddpa->clone_snaps);
1806 ASSERT3U(snap->ds->ds_phys->ds_prev_snap_obj, ==, origin_ds->ds_object);
1807 dsl_deadlist_space_range(&snap->ds->ds_deadlist,
1808 origin_ds->ds_phys->ds_prev_snap_txg, UINT64_MAX,
1809 &ddpa->unique, &unused, &unused);
1810
1811 /*
1812 * Walk the snapshots that we are moving
1813 *
1814 * Compute space to transfer. Consider the incremental changes
1815 * to used by each snapshot:
1816 * (my used) = (prev's used) + (blocks born) - (blocks killed)
1817 * So each snapshot gave birth to:
1818 * (blocks born) = (my used) - (prev's used) + (blocks killed)
1819 * So a sequence would look like:
1820 * (uN - u(N-1) + kN) + ... + (u1 - u0 + k1) + (u0 - 0 + k0)
1821 * Which simplifies to:
1822 * uN + kN + kN-1 + ... + k1 + k0
1823 * Note however, if we stop before we reach the ORIGIN we get:
1824 * uN + kN + kN-1 + ... + kM - uM-1
1825 */
1826 ddpa->used = origin_ds->ds_phys->ds_referenced_bytes;
1827 ddpa->comp = origin_ds->ds_phys->ds_compressed_bytes;
1828 ddpa->uncomp = origin_ds->ds_phys->ds_uncompressed_bytes;
1829 for (snap = list_head(&ddpa->shared_snaps); snap;
1830 snap = list_next(&ddpa->shared_snaps, snap)) {
1831 uint64_t val, dlused, dlcomp, dluncomp;
1832 dsl_dataset_t *ds = snap->ds;
1833
1834 /*
1835 * If there are long holds, we won't be able to evict
1836 * the objset.
1837 */
1838 if (dsl_dataset_long_held(ds)) {
1839 err = SET_ERROR(EBUSY);
1840 goto out;
1841 }
1842
1843 /* Check that the snapshot name does not conflict */
1844 VERIFY0(dsl_dataset_get_snapname(ds));
1845 err = dsl_dataset_snap_lookup(hds, ds->ds_snapname, &val);
1846 if (err == 0) {
1847 (void) strcpy(ddpa->err_ds, snap->ds->ds_snapname);
1848 err = SET_ERROR(EEXIST);
1849 goto out;
1850 }
1851 if (err != ENOENT)
1852 goto out;
1853
1854 /* The very first snapshot does not have a deadlist */
1855 if (ds->ds_phys->ds_prev_snap_obj == 0)
1856 continue;
1857
1858 dsl_deadlist_space(&ds->ds_deadlist,
1859 &dlused, &dlcomp, &dluncomp);
1860 ddpa->used += dlused;
1861 ddpa->comp += dlcomp;
1862 ddpa->uncomp += dluncomp;
1863 }
1864
1865 /*
1866 * If we are a clone of a clone then we never reached ORIGIN,
1867 * so we need to subtract out the clone origin's used space.
1868 */
1869 if (ddpa->origin_origin) {
1870 ddpa->used -= ddpa->origin_origin->ds_phys->ds_referenced_bytes;
1871 ddpa->comp -= ddpa->origin_origin->ds_phys->ds_compressed_bytes;
1872 ddpa->uncomp -=
1873 ddpa->origin_origin->ds_phys->ds_uncompressed_bytes;
1874 }
1875
1876 /* Check that there is enough space here */
1877 err = dsl_dir_transfer_possible(origin_ds->ds_dir, hds->ds_dir,
1878 ddpa->used);
1879 if (err != 0)
1880 goto out;
1881
1882 /*
1883 * Compute the amounts of space that will be used by snapshots
1884 * after the promotion (for both origin and clone). For each,
1885 * it is the amount of space that will be on all of their
1886 * deadlists (that was not born before their new origin).
1887 */
1888 if (hds->ds_dir->dd_phys->dd_flags & DD_FLAG_USED_BREAKDOWN) {
1889 uint64_t space;
1890
1891 /*
1892 * Note, typically this will not be a clone of a clone,
1893 * so dd_origin_txg will be < TXG_INITIAL, so
1894 * these snaplist_space() -> dsl_deadlist_space_range()
1895 * calls will be fast because they do not have to
1896 * iterate over all bps.
1897 */
1898 snap = list_head(&ddpa->origin_snaps);
1899 err = snaplist_space(&ddpa->shared_snaps,
1900 snap->ds->ds_dir->dd_origin_txg, &ddpa->cloneusedsnap);
1901 if (err != 0)
1902 goto out;
1903
1904 err = snaplist_space(&ddpa->clone_snaps,
1905 snap->ds->ds_dir->dd_origin_txg, &space);
1906 if (err != 0)
1907 goto out;
1908 ddpa->cloneusedsnap += space;
1909 }
1910 if (origin_ds->ds_dir->dd_phys->dd_flags & DD_FLAG_USED_BREAKDOWN) {
1911 err = snaplist_space(&ddpa->origin_snaps,
1912 origin_ds->ds_phys->ds_creation_txg, &ddpa->originusedsnap);
1913 if (err != 0)
1914 goto out;
1915 }
1916
1917 out:
1918 promote_rele(ddpa, FTAG);
1919 return (err);
1920 }
1921
1922 static void
1923 dsl_dataset_promote_sync(void *arg, dmu_tx_t *tx)
1924 {
1925 dsl_dataset_promote_arg_t *ddpa = arg;
1926 dsl_pool_t *dp = dmu_tx_pool(tx);
1927 dsl_dataset_t *hds;
1928 struct promotenode *snap;
1929 dsl_dataset_t *origin_ds;
1930 dsl_dataset_t *origin_head;
1931 dsl_dir_t *dd;
1932 dsl_dir_t *odd = NULL;
1933 uint64_t oldnext_obj;
1934 int64_t delta;
1935
1936 VERIFY0(promote_hold(ddpa, dp, FTAG));
1937 hds = ddpa->ddpa_clone;
1938
1939 ASSERT0(hds->ds_phys->ds_flags & DS_FLAG_NOPROMOTE);
1940
1941 snap = list_head(&ddpa->shared_snaps);
1942 origin_ds = snap->ds;
1943 dd = hds->ds_dir;
1944
1945 snap = list_head(&ddpa->origin_snaps);
1946 origin_head = snap->ds;
1947
1948 /*
1949 * We need to explicitly open odd, since origin_ds's dd will be
1950 * changing.
1951 */
1952 VERIFY0(dsl_dir_hold_obj(dp, origin_ds->ds_dir->dd_object,
1953 NULL, FTAG, &odd));
1954
1955 /* change origin's next snap */
1956 dmu_buf_will_dirty(origin_ds->ds_dbuf, tx);
1957 oldnext_obj = origin_ds->ds_phys->ds_next_snap_obj;
1958 snap = list_tail(&ddpa->clone_snaps);
1959 ASSERT3U(snap->ds->ds_phys->ds_prev_snap_obj, ==, origin_ds->ds_object);
1960 origin_ds->ds_phys->ds_next_snap_obj = snap->ds->ds_object;
1961
1962 /* change the origin's next clone */
1963 if (origin_ds->ds_phys->ds_next_clones_obj) {
1964 dsl_dataset_remove_from_next_clones(origin_ds,
1965 snap->ds->ds_object, tx);
1966 VERIFY0(zap_add_int(dp->dp_meta_objset,
1967 origin_ds->ds_phys->ds_next_clones_obj,
1968 oldnext_obj, tx));
1969 }
1970
1971 /* change origin */
1972 dmu_buf_will_dirty(dd->dd_dbuf, tx);
1973 ASSERT3U(dd->dd_phys->dd_origin_obj, ==, origin_ds->ds_object);
1974 dd->dd_phys->dd_origin_obj = odd->dd_phys->dd_origin_obj;
1975 dd->dd_origin_txg = origin_head->ds_dir->dd_origin_txg;
1976 dmu_buf_will_dirty(odd->dd_dbuf, tx);
1977 odd->dd_phys->dd_origin_obj = origin_ds->ds_object;
1978 origin_head->ds_dir->dd_origin_txg =
1979 origin_ds->ds_phys->ds_creation_txg;
1980
1981 /* change dd_clone entries */
1982 if (spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) {
1983 VERIFY0(zap_remove_int(dp->dp_meta_objset,
1984 odd->dd_phys->dd_clones, hds->ds_object, tx));
1985 VERIFY0(zap_add_int(dp->dp_meta_objset,
1986 ddpa->origin_origin->ds_dir->dd_phys->dd_clones,
1987 hds->ds_object, tx));
1988
1989 VERIFY0(zap_remove_int(dp->dp_meta_objset,
1990 ddpa->origin_origin->ds_dir->dd_phys->dd_clones,
1991 origin_head->ds_object, tx));
1992 if (dd->dd_phys->dd_clones == 0) {
1993 dd->dd_phys->dd_clones = zap_create(dp->dp_meta_objset,
1994 DMU_OT_DSL_CLONES, DMU_OT_NONE, 0, tx);
1995 }
1996 VERIFY0(zap_add_int(dp->dp_meta_objset,
1997 dd->dd_phys->dd_clones, origin_head->ds_object, tx));
1998 }
1999
2000 /* move snapshots to this dir */
2001 for (snap = list_head(&ddpa->shared_snaps); snap;
2002 snap = list_next(&ddpa->shared_snaps, snap)) {
2003 dsl_dataset_t *ds = snap->ds;
2004
2005 /*
2006 * Property callbacks are registered to a particular
2007 * dsl_dir. Since ours is changing, evict the objset
2008 * so that they will be unregistered from the old dsl_dir.
2009 */
2010 if (ds->ds_objset) {
2011 dmu_objset_evict(ds->ds_objset);
2012 ds->ds_objset = NULL;
2013 }
2014
2015 /* move snap name entry */
2016 VERIFY0(dsl_dataset_get_snapname(ds));
2017 VERIFY0(dsl_dataset_snap_remove(origin_head,
2018 ds->ds_snapname, tx));
2019 VERIFY0(zap_add(dp->dp_meta_objset,
2020 hds->ds_phys->ds_snapnames_zapobj, ds->ds_snapname,
2021 8, 1, &ds->ds_object, tx));
2022
2023 /* change containing dsl_dir */
2024 dmu_buf_will_dirty(ds->ds_dbuf, tx);
2025 ASSERT3U(ds->ds_phys->ds_dir_obj, ==, odd->dd_object);
2026 ds->ds_phys->ds_dir_obj = dd->dd_object;
2027 ASSERT3P(ds->ds_dir, ==, odd);
2028 dsl_dir_rele(ds->ds_dir, ds);
2029 VERIFY0(dsl_dir_hold_obj(dp, dd->dd_object,
2030 NULL, ds, &ds->ds_dir));
2031
2032 /* move any clone references */
2033 if (ds->ds_phys->ds_next_clones_obj &&
2034 spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) {
2035 zap_cursor_t zc;
2036 zap_attribute_t za;
2037
2038 for (zap_cursor_init(&zc, dp->dp_meta_objset,
2039 ds->ds_phys->ds_next_clones_obj);
2040 zap_cursor_retrieve(&zc, &za) == 0;
2041 zap_cursor_advance(&zc)) {
2042 dsl_dataset_t *cnds;
2043 uint64_t o;
2044
2045 if (za.za_first_integer == oldnext_obj) {
2046 /*
2047 * We've already moved the
2048 * origin's reference.
2049 */
2050 continue;
2051 }
2052
2053 VERIFY0(dsl_dataset_hold_obj(dp,
2054 za.za_first_integer, FTAG, &cnds));
2055 o = cnds->ds_dir->dd_phys->dd_head_dataset_obj;
2056
2057 VERIFY0(zap_remove_int(dp->dp_meta_objset,
2058 odd->dd_phys->dd_clones, o, tx));
2059 VERIFY0(zap_add_int(dp->dp_meta_objset,
2060 dd->dd_phys->dd_clones, o, tx));
2061 dsl_dataset_rele(cnds, FTAG);
2062 }
2063 zap_cursor_fini(&zc);
2064 }
2065
2066 ASSERT(!dsl_prop_hascb(ds));
2067 }
2068
2069 /*
2070 * Change space accounting.
2071 * Note, pa->*usedsnap and dd_used_breakdown[SNAP] will either
2072 * both be valid, or both be 0 (resulting in delta == 0). This
2073 * is true for each of {clone,origin} independently.
2074 */
2075
2076 delta = ddpa->cloneusedsnap -
2077 dd->dd_phys->dd_used_breakdown[DD_USED_SNAP];
2078 ASSERT3S(delta, >=, 0);
2079 ASSERT3U(ddpa->used, >=, delta);
2080 dsl_dir_diduse_space(dd, DD_USED_SNAP, delta, 0, 0, tx);
2081 dsl_dir_diduse_space(dd, DD_USED_HEAD,
2082 ddpa->used - delta, ddpa->comp, ddpa->uncomp, tx);
2083
2084 delta = ddpa->originusedsnap -
2085 odd->dd_phys->dd_used_breakdown[DD_USED_SNAP];
2086 ASSERT3S(delta, <=, 0);
2087 ASSERT3U(ddpa->used, >=, -delta);
2088 dsl_dir_diduse_space(odd, DD_USED_SNAP, delta, 0, 0, tx);
2089 dsl_dir_diduse_space(odd, DD_USED_HEAD,
2090 -ddpa->used - delta, -ddpa->comp, -ddpa->uncomp, tx);
2091
2092 origin_ds->ds_phys->ds_unique_bytes = ddpa->unique;
2093
2094 /* log history record */
2095 spa_history_log_internal_ds(hds, "promote", tx, "");
2096
2097 dsl_dir_rele(odd, FTAG);
2098 promote_rele(ddpa, FTAG);
2099 }
2100
2101 /*
2102 * Make a list of dsl_dataset_t's for the snapshots between first_obj
2103 * (exclusive) and last_obj (inclusive). The list will be in reverse
2104 * order (last_obj will be the list_head()). If first_obj == 0, do all
2105 * snapshots back to this dataset's origin.
2106 */
2107 static int
2108 snaplist_make(dsl_pool_t *dp,
2109 uint64_t first_obj, uint64_t last_obj, list_t *l, void *tag)
2110 {
2111 uint64_t obj = last_obj;
2112
2113 list_create(l, sizeof (struct promotenode),
2114 offsetof(struct promotenode, link));
2115
2116 while (obj != first_obj) {
2117 dsl_dataset_t *ds;
2118 struct promotenode *snap;
2119 int err;
2120
2121 err = dsl_dataset_hold_obj(dp, obj, tag, &ds);
2122 ASSERT(err != ENOENT);
2123 if (err != 0)
2124 return (err);
2125
2126 if (first_obj == 0)
2127 first_obj = ds->ds_dir->dd_phys->dd_origin_obj;
2128
2129 snap = kmem_alloc(sizeof (*snap), KM_SLEEP);
2130 snap->ds = ds;
2131 list_insert_tail(l, snap);
2132 obj = ds->ds_phys->ds_prev_snap_obj;
2133 }
2134
2135 return (0);
2136 }
2137
2138 static int
2139 snaplist_space(list_t *l, uint64_t mintxg, uint64_t *spacep)
2140 {
2141 struct promotenode *snap;
2142
2143 *spacep = 0;
2144 for (snap = list_head(l); snap; snap = list_next(l, snap)) {
2145 uint64_t used, comp, uncomp;
2146 dsl_deadlist_space_range(&snap->ds->ds_deadlist,
2147 mintxg, UINT64_MAX, &used, &comp, &uncomp);
2148 *spacep += used;
2149 }
2150 return (0);
2151 }
2152
2153 static void
2154 snaplist_destroy(list_t *l, void *tag)
2155 {
2156 struct promotenode *snap;
2157
2158 if (l == NULL || !list_link_active(&l->list_head))
2159 return;
2160
2161 while ((snap = list_tail(l)) != NULL) {
2162 list_remove(l, snap);
2163 dsl_dataset_rele(snap->ds, tag);
2164 kmem_free(snap, sizeof (*snap));
2165 }
2166 list_destroy(l);
2167 }
2168
2169 static int
2170 promote_hold(dsl_dataset_promote_arg_t *ddpa, dsl_pool_t *dp, void *tag)
2171 {
2172 int error;
2173 dsl_dir_t *dd;
2174 struct promotenode *snap;
2175
2176 error = dsl_dataset_hold(dp, ddpa->ddpa_clonename, tag,
2177 &ddpa->ddpa_clone);
2178 if (error != 0)
2179 return (error);
2180 dd = ddpa->ddpa_clone->ds_dir;
2181
2182 if (dsl_dataset_is_snapshot(ddpa->ddpa_clone) ||
2183 !dsl_dir_is_clone(dd)) {
2184 dsl_dataset_rele(ddpa->ddpa_clone, tag);
2185 return (SET_ERROR(EINVAL));
2186 }
2187
2188 error = snaplist_make(dp, 0, dd->dd_phys->dd_origin_obj,
2189 &ddpa->shared_snaps, tag);
2190 if (error != 0)
2191 goto out;
2192
2193 error = snaplist_make(dp, 0, ddpa->ddpa_clone->ds_object,
2194 &ddpa->clone_snaps, tag);
2195 if (error != 0)
2196 goto out;
2197
2198 snap = list_head(&ddpa->shared_snaps);
2199 ASSERT3U(snap->ds->ds_object, ==, dd->dd_phys->dd_origin_obj);
2200 error = snaplist_make(dp, dd->dd_phys->dd_origin_obj,
2201 snap->ds->ds_dir->dd_phys->dd_head_dataset_obj,
2202 &ddpa->origin_snaps, tag);
2203 if (error != 0)
2204 goto out;
2205
2206 if (snap->ds->ds_dir->dd_phys->dd_origin_obj != 0) {
2207 error = dsl_dataset_hold_obj(dp,
2208 snap->ds->ds_dir->dd_phys->dd_origin_obj,
2209 tag, &ddpa->origin_origin);
2210 if (error != 0)
2211 goto out;
2212 }
2213 out:
2214 if (error != 0)
2215 promote_rele(ddpa, tag);
2216 return (error);
2217 }
2218
2219 static void
2220 promote_rele(dsl_dataset_promote_arg_t *ddpa, void *tag)
2221 {
2222 snaplist_destroy(&ddpa->shared_snaps, tag);
2223 snaplist_destroy(&ddpa->clone_snaps, tag);
2224 snaplist_destroy(&ddpa->origin_snaps, tag);
2225 if (ddpa->origin_origin != NULL)
2226 dsl_dataset_rele(ddpa->origin_origin, tag);
2227 dsl_dataset_rele(ddpa->ddpa_clone, tag);
2228 }
2229
2230 /*
2231 * Promote a clone.
2232 *
2233 * If it fails due to a conflicting snapshot name, "conflsnap" will be filled
2234 * in with the name. (It must be at least MAXNAMELEN bytes long.)
2235 */
2236 int
2237 dsl_dataset_promote(const char *name, char *conflsnap)
2238 {
2239 dsl_dataset_promote_arg_t ddpa = { 0 };
2240 uint64_t numsnaps;
2241 int error;
2242 objset_t *os;
2243
2244 /*
2245 * We will modify space proportional to the number of
2246 * snapshots. Compute numsnaps.
2247 */
2248 error = dmu_objset_hold(name, FTAG, &os);
2249 if (error != 0)
2250 return (error);
2251 error = zap_count(dmu_objset_pool(os)->dp_meta_objset,
2252 dmu_objset_ds(os)->ds_phys->ds_snapnames_zapobj, &numsnaps);
2253 dmu_objset_rele(os, FTAG);
2254 if (error != 0)
2255 return (error);
2256
2257 ddpa.ddpa_clonename = name;
2258 ddpa.err_ds = conflsnap;
2259
2260 return (dsl_sync_task(name, dsl_dataset_promote_check,
2261 dsl_dataset_promote_sync, &ddpa, 2 + numsnaps));
2262 }
2263
2264 int
2265 dsl_dataset_clone_swap_check_impl(dsl_dataset_t *clone,
2266 dsl_dataset_t *origin_head, boolean_t force)
2267 {
2268 int64_t unused_refres_delta;
2269
2270 /* they should both be heads */
2271 if (dsl_dataset_is_snapshot(clone) ||
2272 dsl_dataset_is_snapshot(origin_head))
2273 return (SET_ERROR(EINVAL));
2274
2275 /* the branch point should be just before them */
2276 if (clone->ds_prev != origin_head->ds_prev)
2277 return (SET_ERROR(EINVAL));
2278
2279 /* clone should be the clone (unless they are unrelated) */
2280 if (clone->ds_prev != NULL &&
2281 clone->ds_prev != clone->ds_dir->dd_pool->dp_origin_snap &&
2282 origin_head->ds_object !=
2283 clone->ds_prev->ds_phys->ds_next_snap_obj)
2284 return (SET_ERROR(EINVAL));
2285
2286 /* the clone should be a child of the origin */
2287 if (clone->ds_dir->dd_parent != origin_head->ds_dir)
2288 return (SET_ERROR(EINVAL));
2289
2290 /* origin_head shouldn't be modified unless 'force' */
2291 if (!force && dsl_dataset_modified_since_lastsnap(origin_head))
2292 return (SET_ERROR(ETXTBSY));
2293
2294 /* origin_head should have no long holds (e.g. is not mounted) */
2295 if (dsl_dataset_long_held(origin_head))
2296 return (SET_ERROR(EBUSY));
2297
2298 /* check amount of any unconsumed refreservation */
2299 unused_refres_delta =
2300 (int64_t)MIN(origin_head->ds_reserved,
2301 origin_head->ds_phys->ds_unique_bytes) -
2302 (int64_t)MIN(origin_head->ds_reserved,
2303 clone->ds_phys->ds_unique_bytes);
2304
2305 if (unused_refres_delta > 0 &&
2306 unused_refres_delta >
2307 dsl_dir_space_available(origin_head->ds_dir, NULL, 0, TRUE))
2308 return (SET_ERROR(ENOSPC));
2309
2310 /* clone can't be over the head's refquota */
2311 if (origin_head->ds_quota != 0 &&
2312 clone->ds_phys->ds_referenced_bytes > origin_head->ds_quota)
2313 return (SET_ERROR(EDQUOT));
2314
2315 return (0);
2316 }
2317
2318 void
2319 dsl_dataset_clone_swap_sync_impl(dsl_dataset_t *clone,
2320 dsl_dataset_t *origin_head, dmu_tx_t *tx)
2321 {
2322 dsl_pool_t *dp = dmu_tx_pool(tx);
2323 int64_t unused_refres_delta;
2324
2325 ASSERT(clone->ds_reserved == 0);
2326 ASSERT(origin_head->ds_quota == 0 ||
2327 clone->ds_phys->ds_unique_bytes <= origin_head->ds_quota);
2328
2329 dmu_buf_will_dirty(clone->ds_dbuf, tx);
2330 dmu_buf_will_dirty(origin_head->ds_dbuf, tx);
2331
2332 if (clone->ds_objset != NULL) {
2333 dmu_objset_evict(clone->ds_objset);
2334 clone->ds_objset = NULL;
2335 }
2336
2337 if (origin_head->ds_objset != NULL) {
2338 dmu_objset_evict(origin_head->ds_objset);
2339 origin_head->ds_objset = NULL;
2340 }
2341
2342 unused_refres_delta =
2343 (int64_t)MIN(origin_head->ds_reserved,
2344 origin_head->ds_phys->ds_unique_bytes) -
2345 (int64_t)MIN(origin_head->ds_reserved,
2346 clone->ds_phys->ds_unique_bytes);
2347
2348 /*
2349 * Reset origin's unique bytes, if it exists.
2350 */
2351 if (clone->ds_prev) {
2352 dsl_dataset_t *origin = clone->ds_prev;
2353 uint64_t comp, uncomp;
2354
2355 dmu_buf_will_dirty(origin->ds_dbuf, tx);
2356 dsl_deadlist_space_range(&clone->ds_deadlist,
2357 origin->ds_phys->ds_prev_snap_txg, UINT64_MAX,
2358 &origin->ds_phys->ds_unique_bytes, &comp, &uncomp);
2359 }
2360
2361 /* swap blkptrs */
2362 {
2363 blkptr_t tmp;
2364 tmp = origin_head->ds_phys->ds_bp;
2365 origin_head->ds_phys->ds_bp = clone->ds_phys->ds_bp;
2366 clone->ds_phys->ds_bp = tmp;
2367 }
2368
2369 /* set dd_*_bytes */
2370 {
2371 int64_t dused, dcomp, duncomp;
2372 uint64_t cdl_used, cdl_comp, cdl_uncomp;
2373 uint64_t odl_used, odl_comp, odl_uncomp;
2374
2375 ASSERT3U(clone->ds_dir->dd_phys->
2376 dd_used_breakdown[DD_USED_SNAP], ==, 0);
2377
2378 dsl_deadlist_space(&clone->ds_deadlist,
2379 &cdl_used, &cdl_comp, &cdl_uncomp);
2380 dsl_deadlist_space(&origin_head->ds_deadlist,
2381 &odl_used, &odl_comp, &odl_uncomp);
2382
2383 dused = clone->ds_phys->ds_referenced_bytes + cdl_used -
2384 (origin_head->ds_phys->ds_referenced_bytes + odl_used);
2385 dcomp = clone->ds_phys->ds_compressed_bytes + cdl_comp -
2386 (origin_head->ds_phys->ds_compressed_bytes + odl_comp);
2387 duncomp = clone->ds_phys->ds_uncompressed_bytes +
2388 cdl_uncomp -
2389 (origin_head->ds_phys->ds_uncompressed_bytes + odl_uncomp);
2390
2391 dsl_dir_diduse_space(origin_head->ds_dir, DD_USED_HEAD,
2392 dused, dcomp, duncomp, tx);
2393 dsl_dir_diduse_space(clone->ds_dir, DD_USED_HEAD,
2394 -dused, -dcomp, -duncomp, tx);
2395
2396 /*
2397 * The difference in the space used by snapshots is the
2398 * difference in snapshot space due to the head's
2399 * deadlist (since that's the only thing that's
2400 * changing that affects the snapused).
2401 */
2402 dsl_deadlist_space_range(&clone->ds_deadlist,
2403 origin_head->ds_dir->dd_origin_txg, UINT64_MAX,
2404 &cdl_used, &cdl_comp, &cdl_uncomp);
2405 dsl_deadlist_space_range(&origin_head->ds_deadlist,
2406 origin_head->ds_dir->dd_origin_txg, UINT64_MAX,
2407 &odl_used, &odl_comp, &odl_uncomp);
2408 dsl_dir_transfer_space(origin_head->ds_dir, cdl_used - odl_used,
2409 DD_USED_HEAD, DD_USED_SNAP, tx);
2410 }
2411
2412 /* swap ds_*_bytes */
2413 SWITCH64(origin_head->ds_phys->ds_referenced_bytes,
2414 clone->ds_phys->ds_referenced_bytes);
2415 SWITCH64(origin_head->ds_phys->ds_compressed_bytes,
2416 clone->ds_phys->ds_compressed_bytes);
2417 SWITCH64(origin_head->ds_phys->ds_uncompressed_bytes,
2418 clone->ds_phys->ds_uncompressed_bytes);
2419 SWITCH64(origin_head->ds_phys->ds_unique_bytes,
2420 clone->ds_phys->ds_unique_bytes);
2421
2422 /* apply any parent delta for change in unconsumed refreservation */
2423 dsl_dir_diduse_space(origin_head->ds_dir, DD_USED_REFRSRV,
2424 unused_refres_delta, 0, 0, tx);
2425
2426 /*
2427 * Swap deadlists.
2428 */
2429 dsl_deadlist_close(&clone->ds_deadlist);
2430 dsl_deadlist_close(&origin_head->ds_deadlist);
2431 SWITCH64(origin_head->ds_phys->ds_deadlist_obj,
2432 clone->ds_phys->ds_deadlist_obj);
2433 dsl_deadlist_open(&clone->ds_deadlist, dp->dp_meta_objset,
2434 clone->ds_phys->ds_deadlist_obj);
2435 dsl_deadlist_open(&origin_head->ds_deadlist, dp->dp_meta_objset,
2436 origin_head->ds_phys->ds_deadlist_obj);
2437
2438 dsl_scan_ds_clone_swapped(origin_head, clone, tx);
2439
2440 spa_history_log_internal_ds(clone, "clone swap", tx,
2441 "parent=%s", origin_head->ds_dir->dd_myname);
2442 }
2443
2444 /*
2445 * Given a pool name and a dataset object number in that pool,
2446 * return the name of that dataset.
2447 */
2448 int
2449 dsl_dsobj_to_dsname(char *pname, uint64_t obj, char *buf)
2450 {
2451 dsl_pool_t *dp;
2452 dsl_dataset_t *ds;
2453 int error;
2454
2455 error = dsl_pool_hold(pname, FTAG, &dp);
2456 if (error != 0)
2457 return (error);
2458
2459 error = dsl_dataset_hold_obj(dp, obj, FTAG, &ds);
2460 if (error == 0) {
2461 dsl_dataset_name(ds, buf);
2462 dsl_dataset_rele(ds, FTAG);
2463 }
2464 dsl_pool_rele(dp, FTAG);
2465
2466 return (error);
2467 }
2468
2469 int
2470 dsl_dataset_check_quota(dsl_dataset_t *ds, boolean_t check_quota,
2471 uint64_t asize, uint64_t inflight, uint64_t *used, uint64_t *ref_rsrv)
2472 {
2473 int error = 0;
2474
2475 ASSERT3S(asize, >, 0);
2476
2477 /*
2478 * *ref_rsrv is the portion of asize that will come from any
2479 * unconsumed refreservation space.
2480 */
2481 *ref_rsrv = 0;
2482
2483 mutex_enter(&ds->ds_lock);
2484 /*
2485 * Make a space adjustment for reserved bytes.
2486 */
2487 if (ds->ds_reserved > ds->ds_phys->ds_unique_bytes) {
2488 ASSERT3U(*used, >=,
2489 ds->ds_reserved - ds->ds_phys->ds_unique_bytes);
2490 *used -= (ds->ds_reserved - ds->ds_phys->ds_unique_bytes);
2491 *ref_rsrv =
2492 asize - MIN(asize, parent_delta(ds, asize + inflight));
2493 }
2494
2495 if (!check_quota || ds->ds_quota == 0) {
2496 mutex_exit(&ds->ds_lock);
2497 return (0);
2498 }
2499 /*
2500 * If they are requesting more space, and our current estimate
2501 * is over quota, they get to try again unless the actual
2502 * on-disk is over quota and there are no pending changes (which
2503 * may free up space for us).
2504 */
2505 if (ds->ds_phys->ds_referenced_bytes + inflight >= ds->ds_quota) {
2506 if (inflight > 0 ||
2507 ds->ds_phys->ds_referenced_bytes < ds->ds_quota)
2508 error = SET_ERROR(ERESTART);
2509 else
2510 error = SET_ERROR(EDQUOT);
2511 }
2512 mutex_exit(&ds->ds_lock);
2513
2514 return (error);
2515 }
2516
2517 typedef struct dsl_dataset_set_qr_arg {
2518 const char *ddsqra_name;
2519 zprop_source_t ddsqra_source;
2520 uint64_t ddsqra_value;
2521 } dsl_dataset_set_qr_arg_t;
2522
2523
2524 /* ARGSUSED */
2525 static int
2526 dsl_dataset_set_refquota_check(void *arg, dmu_tx_t *tx)
2527 {
2528 dsl_dataset_set_qr_arg_t *ddsqra = arg;
2529 dsl_pool_t *dp = dmu_tx_pool(tx);
2530 dsl_dataset_t *ds;
2531 int error;
2532 uint64_t newval;
2533
2534 if (spa_version(dp->dp_spa) < SPA_VERSION_REFQUOTA)
2535 return (SET_ERROR(ENOTSUP));
2536
2537 error = dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds);
2538 if (error != 0)
2539 return (error);
2540
2541 if (dsl_dataset_is_snapshot(ds)) {
2542 dsl_dataset_rele(ds, FTAG);
2543 return (SET_ERROR(EINVAL));
2544 }
2545
2546 error = dsl_prop_predict(ds->ds_dir,
2547 zfs_prop_to_name(ZFS_PROP_REFQUOTA),
2548 ddsqra->ddsqra_source, ddsqra->ddsqra_value, &newval);
2549 if (error != 0) {
2550 dsl_dataset_rele(ds, FTAG);
2551 return (error);
2552 }
2553
2554 if (newval == 0) {
2555 dsl_dataset_rele(ds, FTAG);
2556 return (0);
2557 }
2558
2559 if (newval < ds->ds_phys->ds_referenced_bytes ||
2560 newval < ds->ds_reserved) {
2561 dsl_dataset_rele(ds, FTAG);
2562 return (SET_ERROR(ENOSPC));
2563 }
2564
2565 dsl_dataset_rele(ds, FTAG);
2566 return (0);
2567 }
2568
2569 static void
2570 dsl_dataset_set_refquota_sync(void *arg, dmu_tx_t *tx)
2571 {
2572 dsl_dataset_set_qr_arg_t *ddsqra = arg;
2573 dsl_pool_t *dp = dmu_tx_pool(tx);
2574 dsl_dataset_t *ds;
2575 uint64_t newval;
2576
2577 VERIFY0(dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds));
2578
2579 dsl_prop_set_sync_impl(ds,
2580 zfs_prop_to_name(ZFS_PROP_REFQUOTA),
2581 ddsqra->ddsqra_source, sizeof (ddsqra->ddsqra_value), 1,
2582 &ddsqra->ddsqra_value, tx);
2583
2584 VERIFY0(dsl_prop_get_int_ds(ds,
2585 zfs_prop_to_name(ZFS_PROP_REFQUOTA), &newval));
2586
2587 if (ds->ds_quota != newval) {
2588 dmu_buf_will_dirty(ds->ds_dbuf, tx);
2589 ds->ds_quota = newval;
2590 }
2591 dsl_dataset_rele(ds, FTAG);
2592 }
2593
2594 int
2595 dsl_dataset_set_refquota(const char *dsname, zprop_source_t source,
2596 uint64_t refquota)
2597 {
2598 dsl_dataset_set_qr_arg_t ddsqra;
2599
2600 ddsqra.ddsqra_name = dsname;
2601 ddsqra.ddsqra_source = source;
2602 ddsqra.ddsqra_value = refquota;
2603
2604 return (dsl_sync_task(dsname, dsl_dataset_set_refquota_check,
2605 dsl_dataset_set_refquota_sync, &ddsqra, 0));
2606 }
2607
2608 static int
2609 dsl_dataset_set_refreservation_check(void *arg, dmu_tx_t *tx)
2610 {
2611 dsl_dataset_set_qr_arg_t *ddsqra = arg;
2612 dsl_pool_t *dp = dmu_tx_pool(tx);
2613 dsl_dataset_t *ds;
2614 int error;
2615 uint64_t newval, unique;
2616
2617 if (spa_version(dp->dp_spa) < SPA_VERSION_REFRESERVATION)
2618 return (SET_ERROR(ENOTSUP));
2619
2620 error = dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds);
2621 if (error != 0)
2622 return (error);
2623
2624 if (dsl_dataset_is_snapshot(ds)) {
2625 dsl_dataset_rele(ds, FTAG);
2626 return (SET_ERROR(EINVAL));
2627 }
2628
2629 error = dsl_prop_predict(ds->ds_dir,
2630 zfs_prop_to_name(ZFS_PROP_REFRESERVATION),
2631 ddsqra->ddsqra_source, ddsqra->ddsqra_value, &newval);
2632 if (error != 0) {
2633 dsl_dataset_rele(ds, FTAG);
2634 return (error);
2635 }
2636
2637 /*
2638 * If we are doing the preliminary check in open context, the
2639 * space estimates may be inaccurate.
2640 */
2641 if (!dmu_tx_is_syncing(tx)) {
2642 dsl_dataset_rele(ds, FTAG);
2643 return (0);
2644 }
2645
2646 mutex_enter(&ds->ds_lock);
2647 if (!DS_UNIQUE_IS_ACCURATE(ds))
2648 dsl_dataset_recalc_head_uniq(ds);
2649 unique = ds->ds_phys->ds_unique_bytes;
2650 mutex_exit(&ds->ds_lock);
2651
2652 if (MAX(unique, newval) > MAX(unique, ds->ds_reserved)) {
2653 uint64_t delta = MAX(unique, newval) -
2654 MAX(unique, ds->ds_reserved);
2655
2656 if (delta >
2657 dsl_dir_space_available(ds->ds_dir, NULL, 0, B_TRUE) ||
2658 (ds->ds_quota > 0 && newval > ds->ds_quota)) {
2659 dsl_dataset_rele(ds, FTAG);
2660 return (SET_ERROR(ENOSPC));
2661 }
2662 }
2663
2664 dsl_dataset_rele(ds, FTAG);
2665 return (0);
2666 }
2667
2668 void
2669 dsl_dataset_set_refreservation_sync_impl(dsl_dataset_t *ds,
2670 zprop_source_t source, uint64_t value, dmu_tx_t *tx)
2671 {
2672 uint64_t newval;
2673 uint64_t unique;
2674 int64_t delta;
2675
2676 dsl_prop_set_sync_impl(ds, zfs_prop_to_name(ZFS_PROP_REFRESERVATION),
2677 source, sizeof (value), 1, &value, tx);
2678
2679 VERIFY0(dsl_prop_get_int_ds(ds,
2680 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), &newval));
2681
2682 dmu_buf_will_dirty(ds->ds_dbuf, tx);
2683 mutex_enter(&ds->ds_dir->dd_lock);
2684 mutex_enter(&ds->ds_lock);
2685 ASSERT(DS_UNIQUE_IS_ACCURATE(ds));
2686 unique = ds->ds_phys->ds_unique_bytes;
2687 delta = MAX(0, (int64_t)(newval - unique)) -
2688 MAX(0, (int64_t)(ds->ds_reserved - unique));
2689 ds->ds_reserved = newval;
2690 mutex_exit(&ds->ds_lock);
2691
2692 dsl_dir_diduse_space(ds->ds_dir, DD_USED_REFRSRV, delta, 0, 0, tx);
2693 mutex_exit(&ds->ds_dir->dd_lock);
2694 }
2695
2696 static void
2697 dsl_dataset_set_refreservation_sync(void *arg, dmu_tx_t *tx)
2698 {
2699 dsl_dataset_set_qr_arg_t *ddsqra = arg;
2700 dsl_pool_t *dp = dmu_tx_pool(tx);
2701 dsl_dataset_t *ds;
2702
2703 VERIFY0(dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds));
2704 dsl_dataset_set_refreservation_sync_impl(ds,
2705 ddsqra->ddsqra_source, ddsqra->ddsqra_value, tx);
2706 dsl_dataset_rele(ds, FTAG);
2707 }
2708
2709 int
2710 dsl_dataset_set_refreservation(const char *dsname, zprop_source_t source,
2711 uint64_t refreservation)
2712 {
2713 dsl_dataset_set_qr_arg_t ddsqra;
2714
2715 ddsqra.ddsqra_name = dsname;
2716 ddsqra.ddsqra_source = source;
2717 ddsqra.ddsqra_value = refreservation;
2718
2719 return (dsl_sync_task(dsname, dsl_dataset_set_refreservation_check,
2720 dsl_dataset_set_refreservation_sync, &ddsqra, 0));
2721 }
2722
2723 /*
2724 * Return (in *usedp) the amount of space written in new that is not
2725 * present in oldsnap. New may be a snapshot or the head. Old must be
2726 * a snapshot before new, in new's filesystem (or its origin). If not then
2727 * fail and return EINVAL.
2728 *
2729 * The written space is calculated by considering two components: First, we
2730 * ignore any freed space, and calculate the written as new's used space
2731 * minus old's used space. Next, we add in the amount of space that was freed
2732 * between the two snapshots, thus reducing new's used space relative to old's.
2733 * Specifically, this is the space that was born before old->ds_creation_txg,
2734 * and freed before new (ie. on new's deadlist or a previous deadlist).
2735 *
2736 * space freed [---------------------]
2737 * snapshots ---O-------O--------O-------O------
2738 * oldsnap new
2739 */
2740 int
2741 dsl_dataset_space_written(dsl_dataset_t *oldsnap, dsl_dataset_t *new,
2742 uint64_t *usedp, uint64_t *compp, uint64_t *uncompp)
2743 {
2744 int err = 0;
2745 uint64_t snapobj;
2746 dsl_pool_t *dp = new->ds_dir->dd_pool;
2747
2748 ASSERT(dsl_pool_config_held(dp));
2749
2750 *usedp = 0;
2751 *usedp += new->ds_phys->ds_referenced_bytes;
2752 *usedp -= oldsnap->ds_phys->ds_referenced_bytes;
2753
2754 *compp = 0;
2755 *compp += new->ds_phys->ds_compressed_bytes;
2756 *compp -= oldsnap->ds_phys->ds_compressed_bytes;
2757
2758 *uncompp = 0;
2759 *uncompp += new->ds_phys->ds_uncompressed_bytes;
2760 *uncompp -= oldsnap->ds_phys->ds_uncompressed_bytes;
2761
2762 snapobj = new->ds_object;
2763 while (snapobj != oldsnap->ds_object) {
2764 dsl_dataset_t *snap;
2765 uint64_t used, comp, uncomp;
2766
2767 if (snapobj == new->ds_object) {
2768 snap = new;
2769 } else {
2770 err = dsl_dataset_hold_obj(dp, snapobj, FTAG, &snap);
2771 if (err != 0)
2772 break;
2773 }
2774
2775 if (snap->ds_phys->ds_prev_snap_txg ==
2776 oldsnap->ds_phys->ds_creation_txg) {
2777 /*
2778 * The blocks in the deadlist can not be born after
2779 * ds_prev_snap_txg, so get the whole deadlist space,
2780 * which is more efficient (especially for old-format
2781 * deadlists). Unfortunately the deadlist code
2782 * doesn't have enough information to make this
2783 * optimization itself.
2784 */
2785 dsl_deadlist_space(&snap->ds_deadlist,
2786 &used, &comp, &uncomp);
2787 } else {
2788 dsl_deadlist_space_range(&snap->ds_deadlist,
2789 0, oldsnap->ds_phys->ds_creation_txg,
2790 &used, &comp, &uncomp);
2791 }
2792 *usedp += used;
2793 *compp += comp;
2794 *uncompp += uncomp;
2795
2796 /*
2797 * If we get to the beginning of the chain of snapshots
2798 * (ds_prev_snap_obj == 0) before oldsnap, then oldsnap
2799 * was not a snapshot of/before new.
2800 */
2801 snapobj = snap->ds_phys->ds_prev_snap_obj;
2802 if (snap != new)
2803 dsl_dataset_rele(snap, FTAG);
2804 if (snapobj == 0) {
2805 err = SET_ERROR(EINVAL);
2806 break;
2807 }
2808
2809 }
2810 return (err);
2811 }
2812
2813 /*
2814 * Return (in *usedp) the amount of space that will be reclaimed if firstsnap,
2815 * lastsnap, and all snapshots in between are deleted.
2816 *
2817 * blocks that would be freed [---------------------------]
2818 * snapshots ---O-------O--------O-------O--------O
2819 * firstsnap lastsnap
2820 *
2821 * This is the set of blocks that were born after the snap before firstsnap,
2822 * (birth > firstsnap->prev_snap_txg) and died before the snap after the
2823 * last snap (ie, is on lastsnap->ds_next->ds_deadlist or an earlier deadlist).
2824 * We calculate this by iterating over the relevant deadlists (from the snap
2825 * after lastsnap, backward to the snap after firstsnap), summing up the
2826 * space on the deadlist that was born after the snap before firstsnap.
2827 */
2828 int
2829 dsl_dataset_space_wouldfree(dsl_dataset_t *firstsnap,
2830 dsl_dataset_t *lastsnap,
2831 uint64_t *usedp, uint64_t *compp, uint64_t *uncompp)
2832 {
2833 int err = 0;
2834 uint64_t snapobj;
2835 dsl_pool_t *dp = firstsnap->ds_dir->dd_pool;
2836
2837 ASSERT(dsl_dataset_is_snapshot(firstsnap));
2838 ASSERT(dsl_dataset_is_snapshot(lastsnap));
2839
2840 /*
2841 * Check that the snapshots are in the same dsl_dir, and firstsnap
2842 * is before lastsnap.
2843 */
2844 if (firstsnap->ds_dir != lastsnap->ds_dir ||
2845 firstsnap->ds_phys->ds_creation_txg >
2846 lastsnap->ds_phys->ds_creation_txg)
2847 return (SET_ERROR(EINVAL));
2848
2849 *usedp = *compp = *uncompp = 0;
2850
2851 snapobj = lastsnap->ds_phys->ds_next_snap_obj;
2852 while (snapobj != firstsnap->ds_object) {
2853 dsl_dataset_t *ds;
2854 uint64_t used, comp, uncomp;
2855
2856 err = dsl_dataset_hold_obj(dp, snapobj, FTAG, &ds);
2857 if (err != 0)
2858 break;
2859
2860 dsl_deadlist_space_range(&ds->ds_deadlist,
2861 firstsnap->ds_phys->ds_prev_snap_txg, UINT64_MAX,
2862 &used, &comp, &uncomp);
2863 *usedp += used;
2864 *compp += comp;
2865 *uncompp += uncomp;
2866
2867 snapobj = ds->ds_phys->ds_prev_snap_obj;
2868 ASSERT3U(snapobj, !=, 0);
2869 dsl_dataset_rele(ds, FTAG);
2870 }
2871 return (err);
2872 }
2873
2874 /*
2875 * Return TRUE if 'earlier' is an earlier snapshot in 'later's timeline.
2876 * For example, they could both be snapshots of the same filesystem, and
2877 * 'earlier' is before 'later'. Or 'earlier' could be the origin of
2878 * 'later's filesystem. Or 'earlier' could be an older snapshot in the origin's
2879 * filesystem. Or 'earlier' could be the origin's origin.
2880 */
2881 boolean_t
2882 dsl_dataset_is_before(dsl_dataset_t *later, dsl_dataset_t *earlier)
2883 {
2884 dsl_pool_t *dp = later->ds_dir->dd_pool;
2885 int error;
2886 boolean_t ret;
2887 dsl_dataset_t *origin;
2888
2889 ASSERT(dsl_pool_config_held(dp));
2890
2891 if (earlier->ds_phys->ds_creation_txg >=
2892 later->ds_phys->ds_creation_txg)
2893 return (B_FALSE);
2894
2895 if (later->ds_dir == earlier->ds_dir)
2896 return (B_TRUE);
2897 if (!dsl_dir_is_clone(later->ds_dir))
2898 return (B_FALSE);
2899
2900 if (later->ds_dir->dd_phys->dd_origin_obj == earlier->ds_object)
2901 return (B_TRUE);
2902 error = dsl_dataset_hold_obj(dp,
2903 later->ds_dir->dd_phys->dd_origin_obj, FTAG, &origin);
2904 if (error != 0)
2905 return (B_FALSE);
2906 ret = dsl_dataset_is_before(origin, earlier);
2907 dsl_dataset_rele(origin, FTAG);
2908 return (ret);
2909 }
2910
2911 #if defined(_KERNEL) && defined(HAVE_SPL)
2912 EXPORT_SYMBOL(dsl_dataset_hold);
2913 EXPORT_SYMBOL(dsl_dataset_hold_obj);
2914 EXPORT_SYMBOL(dsl_dataset_own);
2915 EXPORT_SYMBOL(dsl_dataset_own_obj);
2916 EXPORT_SYMBOL(dsl_dataset_name);
2917 EXPORT_SYMBOL(dsl_dataset_rele);
2918 EXPORT_SYMBOL(dsl_dataset_disown);
2919 EXPORT_SYMBOL(dsl_dataset_tryown);
2920 EXPORT_SYMBOL(dsl_dataset_create_sync);
2921 EXPORT_SYMBOL(dsl_dataset_create_sync_dd);
2922 EXPORT_SYMBOL(dsl_dataset_snapshot_check);
2923 EXPORT_SYMBOL(dsl_dataset_snapshot_sync);
2924 EXPORT_SYMBOL(dsl_dataset_promote);
2925 EXPORT_SYMBOL(dsl_dataset_user_hold);
2926 EXPORT_SYMBOL(dsl_dataset_user_release);
2927 EXPORT_SYMBOL(dsl_dataset_get_holds);
2928 EXPORT_SYMBOL(dsl_dataset_get_blkptr);
2929 EXPORT_SYMBOL(dsl_dataset_set_blkptr);
2930 EXPORT_SYMBOL(dsl_dataset_get_spa);
2931 EXPORT_SYMBOL(dsl_dataset_modified_since_lastsnap);
2932 EXPORT_SYMBOL(dsl_dataset_space_written);
2933 EXPORT_SYMBOL(dsl_dataset_space_wouldfree);
2934 EXPORT_SYMBOL(dsl_dataset_sync);
2935 EXPORT_SYMBOL(dsl_dataset_block_born);
2936 EXPORT_SYMBOL(dsl_dataset_block_kill);
2937 EXPORT_SYMBOL(dsl_dataset_block_freeable);
2938 EXPORT_SYMBOL(dsl_dataset_prev_snap_txg);
2939 EXPORT_SYMBOL(dsl_dataset_dirty);
2940 EXPORT_SYMBOL(dsl_dataset_stats);
2941 EXPORT_SYMBOL(dsl_dataset_fast_stat);
2942 EXPORT_SYMBOL(dsl_dataset_space);
2943 EXPORT_SYMBOL(dsl_dataset_fsid_guid);
2944 EXPORT_SYMBOL(dsl_dsobj_to_dsname);
2945 EXPORT_SYMBOL(dsl_dataset_check_quota);
2946 EXPORT_SYMBOL(dsl_dataset_clone_swap_check_impl);
2947 EXPORT_SYMBOL(dsl_dataset_clone_swap_sync_impl);
2948 #endif
ZFS On Linux mirror for PVE