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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
52 #define SWITCH64(x, y) \
53 { \
54 uint64_t __tmp = (x); \
55 (x) = (y); \
56 (y) = __tmp; \
57 }
58
59 #define DS_REF_MAX (1ULL << 62)
60
61 #define DSL_DEADLIST_BLOCKSIZE SPA_MAXBLOCKSIZE
62
63 /*
64 * Figure out how much of this delta should be propogated to the dsl_dir
65 * layer. If there's a refreservation, that space has already been
66 * partially accounted for in our ancestors.
67 */
68 static int64_t
69 parent_delta(dsl_dataset_t *ds, int64_t delta)
70 {
71 uint64_t old_bytes, new_bytes;
72
73 if (ds->ds_reserved == 0)
74 return (delta);
75
76 old_bytes = MAX(ds->ds_phys->ds_unique_bytes, ds->ds_reserved);
77 new_bytes = MAX(ds->ds_phys->ds_unique_bytes + delta, ds->ds_reserved);
78
79 ASSERT3U(ABS((int64_t)(new_bytes - old_bytes)), <=, ABS(delta));
80 return (new_bytes - old_bytes);
81 }
82
83 void
84 dsl_dataset_block_born(dsl_dataset_t *ds, const blkptr_t *bp, dmu_tx_t *tx)
85 {
86 int used, compressed, uncompressed;
87 int64_t delta;
88
89 used = bp_get_dsize_sync(tx->tx_pool->dp_spa, bp);
90 compressed = BP_GET_PSIZE(bp);
91 uncompressed = BP_GET_UCSIZE(bp);
92
93 dprintf_bp(bp, "ds=%p", ds);
94
95 ASSERT(dmu_tx_is_syncing(tx));
96 /* It could have been compressed away to nothing */
97 if (BP_IS_HOLE(bp))
98 return;
99 ASSERT(BP_GET_TYPE(bp) != DMU_OT_NONE);
100 ASSERT(DMU_OT_IS_VALID(BP_GET_TYPE(bp)));
101 if (ds == NULL) {
102 dsl_pool_mos_diduse_space(tx->tx_pool,
103 used, compressed, uncompressed);
104 return;
105 }
106
107 dmu_buf_will_dirty(ds->ds_dbuf, tx);
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 }
120
121 int
122 dsl_dataset_block_kill(dsl_dataset_t *ds, const blkptr_t *bp, dmu_tx_t *tx,
123 boolean_t async)
124 {
125 int used, compressed, uncompressed;
126
127 if (BP_IS_HOLE(bp))
128 return (0);
129
130 ASSERT(dmu_tx_is_syncing(tx));
131 ASSERT(bp->blk_birth <= tx->tx_txg);
132
133 used = bp_get_dsize_sync(tx->tx_pool->dp_spa, bp);
134 compressed = BP_GET_PSIZE(bp);
135 uncompressed = BP_GET_UCSIZE(bp);
136
137 ASSERT(used > 0);
138 if (ds == NULL) {
139 dsl_free(tx->tx_pool, tx->tx_txg, bp);
140 dsl_pool_mos_diduse_space(tx->tx_pool,
141 -used, -compressed, -uncompressed);
142 return (used);
143 }
144 ASSERT3P(tx->tx_pool, ==, ds->ds_dir->dd_pool);
145
146 ASSERT(!dsl_dataset_is_snapshot(ds));
147 dmu_buf_will_dirty(ds->ds_dbuf, tx);
148
149 if (bp->blk_birth > ds->ds_phys->ds_prev_snap_txg) {
150 int64_t delta;
151
152 dprintf_bp(bp, "freeing ds=%llu", ds->ds_object);
153 dsl_free(tx->tx_pool, tx->tx_txg, bp);
154
155 mutex_enter(&ds->ds_lock);
156 ASSERT(ds->ds_phys->ds_unique_bytes >= used ||
157 !DS_UNIQUE_IS_ACCURATE(ds));
158 delta = parent_delta(ds, -used);
159 ds->ds_phys->ds_unique_bytes -= used;
160 mutex_exit(&ds->ds_lock);
161 dsl_dir_diduse_space(ds->ds_dir, DD_USED_HEAD,
162 delta, -compressed, -uncompressed, tx);
163 dsl_dir_transfer_space(ds->ds_dir, -used - delta,
164 DD_USED_REFRSRV, DD_USED_HEAD, tx);
165 } else {
166 dprintf_bp(bp, "putting on dead list: %s", "");
167 if (async) {
168 /*
169 * We are here as part of zio's write done callback,
170 * which means we're a zio interrupt thread. We can't
171 * call dsl_deadlist_insert() now because it may block
172 * waiting for I/O. Instead, put bp on the deferred
173 * queue and let dsl_pool_sync() finish the job.
174 */
175 bplist_append(&ds->ds_pending_deadlist, bp);
176 } else {
177 dsl_deadlist_insert(&ds->ds_deadlist, bp, tx);
178 }
179 ASSERT3U(ds->ds_prev->ds_object, ==,
180 ds->ds_phys->ds_prev_snap_obj);
181 ASSERT(ds->ds_prev->ds_phys->ds_num_children > 0);
182 /* if (bp->blk_birth > prev prev snap txg) prev unique += bs */
183 if (ds->ds_prev->ds_phys->ds_next_snap_obj ==
184 ds->ds_object && bp->blk_birth >
185 ds->ds_prev->ds_phys->ds_prev_snap_txg) {
186 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx);
187 mutex_enter(&ds->ds_prev->ds_lock);
188 ds->ds_prev->ds_phys->ds_unique_bytes += used;
189 mutex_exit(&ds->ds_prev->ds_lock);
190 }
191 if (bp->blk_birth > ds->ds_dir->dd_origin_txg) {
192 dsl_dir_transfer_space(ds->ds_dir, used,
193 DD_USED_HEAD, DD_USED_SNAP, tx);
194 }
195 }
196 mutex_enter(&ds->ds_lock);
197 ASSERT3U(ds->ds_phys->ds_referenced_bytes, >=, used);
198 ds->ds_phys->ds_referenced_bytes -= used;
199 ASSERT3U(ds->ds_phys->ds_compressed_bytes, >=, compressed);
200 ds->ds_phys->ds_compressed_bytes -= compressed;
201 ASSERT3U(ds->ds_phys->ds_uncompressed_bytes, >=, uncompressed);
202 ds->ds_phys->ds_uncompressed_bytes -= uncompressed;
203 mutex_exit(&ds->ds_lock);
204
205 return (used);
206 }
207
208 uint64_t
209 dsl_dataset_prev_snap_txg(dsl_dataset_t *ds)
210 {
211 uint64_t trysnap = 0;
212
213 if (ds == NULL)
214 return (0);
215 /*
216 * The snapshot creation could fail, but that would cause an
217 * incorrect FALSE return, which would only result in an
218 * overestimation of the amount of space that an operation would
219 * consume, which is OK.
220 *
221 * There's also a small window where we could miss a pending
222 * snapshot, because we could set the sync task in the quiescing
223 * phase. So this should only be used as a guess.
224 */
225 if (ds->ds_trysnap_txg >
226 spa_last_synced_txg(ds->ds_dir->dd_pool->dp_spa))
227 trysnap = ds->ds_trysnap_txg;
228 return (MAX(ds->ds_phys->ds_prev_snap_txg, trysnap));
229 }
230
231 boolean_t
232 dsl_dataset_block_freeable(dsl_dataset_t *ds, const blkptr_t *bp,
233 uint64_t blk_birth)
234 {
235 if (blk_birth <= dsl_dataset_prev_snap_txg(ds))
236 return (B_FALSE);
237
238 ddt_prefetch(dsl_dataset_get_spa(ds), bp);
239
240 return (B_TRUE);
241 }
242
243 /* ARGSUSED */
244 static void
245 dsl_dataset_evict(dmu_buf_t *db, void *dsv)
246 {
247 dsl_dataset_t *ds = dsv;
248
249 ASSERT(ds->ds_owner == NULL);
250
251 unique_remove(ds->ds_fsid_guid);
252
253 if (ds->ds_objset != NULL)
254 dmu_objset_evict(ds->ds_objset);
255
256 if (ds->ds_prev) {
257 dsl_dataset_rele(ds->ds_prev, ds);
258 ds->ds_prev = NULL;
259 }
260
261 bplist_destroy(&ds->ds_pending_deadlist);
262 if (ds->ds_phys->ds_deadlist_obj != 0)
263 dsl_deadlist_close(&ds->ds_deadlist);
264 if (ds->ds_dir)
265 dsl_dir_rele(ds->ds_dir, ds);
266
267 ASSERT(!list_link_active(&ds->ds_synced_link));
268
269 mutex_destroy(&ds->ds_lock);
270 mutex_destroy(&ds->ds_opening_lock);
271 refcount_destroy(&ds->ds_longholds);
272
273 kmem_free(ds, sizeof (dsl_dataset_t));
274 }
275
276 int
277 dsl_dataset_get_snapname(dsl_dataset_t *ds)
278 {
279 dsl_dataset_phys_t *headphys;
280 int err;
281 dmu_buf_t *headdbuf;
282 dsl_pool_t *dp = ds->ds_dir->dd_pool;
283 objset_t *mos = dp->dp_meta_objset;
284
285 if (ds->ds_snapname[0])
286 return (0);
287 if (ds->ds_phys->ds_next_snap_obj == 0)
288 return (0);
289
290 err = dmu_bonus_hold(mos, ds->ds_dir->dd_phys->dd_head_dataset_obj,
291 FTAG, &headdbuf);
292 if (err != 0)
293 return (err);
294 headphys = headdbuf->db_data;
295 err = zap_value_search(dp->dp_meta_objset,
296 headphys->ds_snapnames_zapobj, ds->ds_object, 0, ds->ds_snapname);
297 dmu_buf_rele(headdbuf, FTAG);
298 return (err);
299 }
300
301 int
302 dsl_dataset_snap_lookup(dsl_dataset_t *ds, const char *name, uint64_t *value)
303 {
304 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
305 uint64_t snapobj = ds->ds_phys->ds_snapnames_zapobj;
306 matchtype_t mt;
307 int err;
308
309 if (ds->ds_phys->ds_flags & DS_FLAG_CI_DATASET)
310 mt = MT_FIRST;
311 else
312 mt = MT_EXACT;
313
314 err = zap_lookup_norm(mos, snapobj, name, 8, 1,
315 value, mt, NULL, 0, NULL);
316 if (err == ENOTSUP && mt == MT_FIRST)
317 err = zap_lookup(mos, snapobj, name, 8, 1, value);
318 return (err);
319 }
320
321 int
322 dsl_dataset_snap_remove(dsl_dataset_t *ds, const char *name, dmu_tx_t *tx)
323 {
324 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
325 uint64_t snapobj = ds->ds_phys->ds_snapnames_zapobj;
326 matchtype_t mt;
327 int err;
328
329 dsl_dir_snap_cmtime_update(ds->ds_dir);
330
331 if (ds->ds_phys->ds_flags & DS_FLAG_CI_DATASET)
332 mt = MT_FIRST;
333 else
334 mt = MT_EXACT;
335
336 err = zap_remove_norm(mos, snapobj, name, mt, tx);
337 if (err == ENOTSUP && mt == MT_FIRST)
338 err = zap_remove(mos, snapobj, name, tx);
339 return (err);
340 }
341
342 int
343 dsl_dataset_hold_obj(dsl_pool_t *dp, uint64_t dsobj, void *tag,
344 dsl_dataset_t **dsp)
345 {
346 objset_t *mos = dp->dp_meta_objset;
347 dmu_buf_t *dbuf;
348 dsl_dataset_t *ds;
349 int err;
350 dmu_object_info_t doi;
351
352 ASSERT(dsl_pool_config_held(dp));
353
354 err = dmu_bonus_hold(mos, dsobj, tag, &dbuf);
355 if (err != 0)
356 return (err);
357
358 /* Make sure dsobj has the correct object type. */
359 dmu_object_info_from_db(dbuf, &doi);
360 if (doi.doi_bonus_type != DMU_OT_DSL_DATASET) {
361 dmu_buf_rele(dbuf, tag);
362 return (SET_ERROR(EINVAL));
363 }
364
365 ds = dmu_buf_get_user(dbuf);
366 if (ds == NULL) {
367 dsl_dataset_t *winner = NULL;
368
369 ds = kmem_zalloc(sizeof (dsl_dataset_t), KM_PUSHPAGE);
370 ds->ds_dbuf = dbuf;
371 ds->ds_object = dsobj;
372 ds->ds_phys = dbuf->db_data;
373 list_link_init(&ds->ds_synced_link);
374
375 mutex_init(&ds->ds_lock, NULL, MUTEX_DEFAULT, NULL);
376 mutex_init(&ds->ds_opening_lock, NULL, MUTEX_DEFAULT, NULL);
377 mutex_init(&ds->ds_sendstream_lock, NULL, MUTEX_DEFAULT, NULL);
378 refcount_create(&ds->ds_longholds);
379
380 bplist_create(&ds->ds_pending_deadlist);
381 dsl_deadlist_open(&ds->ds_deadlist,
382 mos, ds->ds_phys->ds_deadlist_obj);
383
384 list_create(&ds->ds_sendstreams, sizeof (dmu_sendarg_t),
385 offsetof(dmu_sendarg_t, dsa_link));
386
387 if (err == 0) {
388 err = dsl_dir_hold_obj(dp,
389 ds->ds_phys->ds_dir_obj, NULL, ds, &ds->ds_dir);
390 }
391 if (err != 0) {
392 mutex_destroy(&ds->ds_lock);
393 mutex_destroy(&ds->ds_opening_lock);
394 refcount_destroy(&ds->ds_longholds);
395 bplist_destroy(&ds->ds_pending_deadlist);
396 dsl_deadlist_close(&ds->ds_deadlist);
397 kmem_free(ds, sizeof (dsl_dataset_t));
398 dmu_buf_rele(dbuf, tag);
399 return (err);
400 }
401
402 if (!dsl_dataset_is_snapshot(ds)) {
403 ds->ds_snapname[0] = '\0';
404 if (ds->ds_phys->ds_prev_snap_obj != 0) {
405 err = dsl_dataset_hold_obj(dp,
406 ds->ds_phys->ds_prev_snap_obj,
407 ds, &ds->ds_prev);
408 }
409 } else {
410 if (zfs_flags & ZFS_DEBUG_SNAPNAMES)
411 err = dsl_dataset_get_snapname(ds);
412 if (err == 0 && ds->ds_phys->ds_userrefs_obj != 0) {
413 err = zap_count(
414 ds->ds_dir->dd_pool->dp_meta_objset,
415 ds->ds_phys->ds_userrefs_obj,
416 &ds->ds_userrefs);
417 }
418 }
419
420 if (err == 0 && !dsl_dataset_is_snapshot(ds)) {
421 err = dsl_prop_get_int_ds(ds,
422 zfs_prop_to_name(ZFS_PROP_REFRESERVATION),
423 &ds->ds_reserved);
424 if (err == 0) {
425 err = dsl_prop_get_int_ds(ds,
426 zfs_prop_to_name(ZFS_PROP_REFQUOTA),
427 &ds->ds_quota);
428 }
429 } else {
430 ds->ds_reserved = ds->ds_quota = 0;
431 }
432
433 if (err != 0 || (winner = dmu_buf_set_user_ie(dbuf, ds,
434 &ds->ds_phys, dsl_dataset_evict)) != NULL) {
435 bplist_destroy(&ds->ds_pending_deadlist);
436 dsl_deadlist_close(&ds->ds_deadlist);
437 if (ds->ds_prev)
438 dsl_dataset_rele(ds->ds_prev, ds);
439 dsl_dir_rele(ds->ds_dir, ds);
440 mutex_destroy(&ds->ds_lock);
441 mutex_destroy(&ds->ds_opening_lock);
442 refcount_destroy(&ds->ds_longholds);
443 kmem_free(ds, sizeof (dsl_dataset_t));
444 if (err != 0) {
445 dmu_buf_rele(dbuf, tag);
446 return (err);
447 }
448 ds = winner;
449 } else {
450 ds->ds_fsid_guid =
451 unique_insert(ds->ds_phys->ds_fsid_guid);
452 }
453 }
454 ASSERT3P(ds->ds_dbuf, ==, dbuf);
455 ASSERT3P(ds->ds_phys, ==, dbuf->db_data);
456 ASSERT(ds->ds_phys->ds_prev_snap_obj != 0 ||
457 spa_version(dp->dp_spa) < SPA_VERSION_ORIGIN ||
458 dp->dp_origin_snap == NULL || ds == dp->dp_origin_snap);
459 *dsp = ds;
460 return (0);
461 }
462
463 int
464 dsl_dataset_hold(dsl_pool_t *dp, const char *name,
465 void *tag, dsl_dataset_t **dsp)
466 {
467 dsl_dir_t *dd;
468 const char *snapname;
469 uint64_t obj;
470 int err = 0;
471
472 err = dsl_dir_hold(dp, name, FTAG, &dd, &snapname);
473 if (err != 0)
474 return (err);
475
476 ASSERT(dsl_pool_config_held(dp));
477 obj = dd->dd_phys->dd_head_dataset_obj;
478 if (obj != 0)
479 err = dsl_dataset_hold_obj(dp, obj, tag, dsp);
480 else
481 err = SET_ERROR(ENOENT);
482
483 /* we may be looking for a snapshot */
484 if (err == 0 && snapname != NULL) {
485 dsl_dataset_t *ds;
486
487 if (*snapname++ != '@') {
488 dsl_dataset_rele(*dsp, tag);
489 dsl_dir_rele(dd, FTAG);
490 return (SET_ERROR(ENOENT));
491 }
492
493 dprintf("looking for snapshot '%s'\n", snapname);
494 err = dsl_dataset_snap_lookup(*dsp, snapname, &obj);
495 if (err == 0)
496 err = dsl_dataset_hold_obj(dp, obj, tag, &ds);
497 dsl_dataset_rele(*dsp, tag);
498
499 if (err == 0) {
500 mutex_enter(&ds->ds_lock);
501 if (ds->ds_snapname[0] == 0)
502 (void) strlcpy(ds->ds_snapname, snapname,
503 sizeof (ds->ds_snapname));
504 mutex_exit(&ds->ds_lock);
505 *dsp = ds;
506 }
507 }
508
509 dsl_dir_rele(dd, FTAG);
510 return (err);
511 }
512
513 int
514 dsl_dataset_own_obj(dsl_pool_t *dp, uint64_t dsobj,
515 void *tag, dsl_dataset_t **dsp)
516 {
517 int err = dsl_dataset_hold_obj(dp, dsobj, tag, dsp);
518 if (err != 0)
519 return (err);
520 if (!dsl_dataset_tryown(*dsp, tag)) {
521 dsl_dataset_rele(*dsp, tag);
522 *dsp = NULL;
523 return (SET_ERROR(EBUSY));
524 }
525 return (0);
526 }
527
528 int
529 dsl_dataset_own(dsl_pool_t *dp, const char *name,
530 void *tag, dsl_dataset_t **dsp)
531 {
532 int err = dsl_dataset_hold(dp, name, tag, dsp);
533 if (err != 0)
534 return (err);
535 if (!dsl_dataset_tryown(*dsp, tag)) {
536 dsl_dataset_rele(*dsp, tag);
537 return (SET_ERROR(EBUSY));
538 }
539 return (0);
540 }
541
542 /*
543 * See the comment above dsl_pool_hold() for details. In summary, a long
544 * hold is used to prevent destruction of a dataset while the pool hold
545 * is dropped, allowing other concurrent operations (e.g. spa_sync()).
546 *
547 * The dataset and pool must be held when this function is called. After it
548 * is called, the pool hold may be released while the dataset is still held
549 * and accessed.
550 */
551 void
552 dsl_dataset_long_hold(dsl_dataset_t *ds, void *tag)
553 {
554 ASSERT(dsl_pool_config_held(ds->ds_dir->dd_pool));
555 (void) refcount_add(&ds->ds_longholds, tag);
556 }
557
558 void
559 dsl_dataset_long_rele(dsl_dataset_t *ds, void *tag)
560 {
561 (void) refcount_remove(&ds->ds_longholds, tag);
562 }
563
564 /* Return B_TRUE if there are any long holds on this dataset. */
565 boolean_t
566 dsl_dataset_long_held(dsl_dataset_t *ds)
567 {
568 return (!refcount_is_zero(&ds->ds_longholds));
569 }
570
571 void
572 dsl_dataset_name(dsl_dataset_t *ds, char *name)
573 {
574 if (ds == NULL) {
575 (void) strcpy(name, "mos");
576 } else {
577 dsl_dir_name(ds->ds_dir, name);
578 VERIFY0(dsl_dataset_get_snapname(ds));
579 if (ds->ds_snapname[0]) {
580 (void) strcat(name, "@");
581 /*
582 * We use a "recursive" mutex so that we
583 * can call dprintf_ds() with ds_lock held.
584 */
585 if (!MUTEX_HELD(&ds->ds_lock)) {
586 mutex_enter(&ds->ds_lock);
587 (void) strcat(name, ds->ds_snapname);
588 mutex_exit(&ds->ds_lock);
589 } else {
590 (void) strcat(name, ds->ds_snapname);
591 }
592 }
593 }
594 }
595
596 void
597 dsl_dataset_rele(dsl_dataset_t *ds, void *tag)
598 {
599 dmu_buf_rele(ds->ds_dbuf, tag);
600 }
601
602 void
603 dsl_dataset_disown(dsl_dataset_t *ds, void *tag)
604 {
605 ASSERT(ds->ds_owner == tag && ds->ds_dbuf != NULL);
606
607 mutex_enter(&ds->ds_lock);
608 ds->ds_owner = NULL;
609 mutex_exit(&ds->ds_lock);
610 dsl_dataset_long_rele(ds, tag);
611 if (ds->ds_dbuf != NULL)
612 dsl_dataset_rele(ds, tag);
613 else
614 dsl_dataset_evict(NULL, ds);
615 }
616
617 boolean_t
618 dsl_dataset_tryown(dsl_dataset_t *ds, void *tag)
619 {
620 boolean_t gotit = FALSE;
621
622 mutex_enter(&ds->ds_lock);
623 if (ds->ds_owner == NULL && !DS_IS_INCONSISTENT(ds)) {
624 ds->ds_owner = tag;
625 dsl_dataset_long_hold(ds, tag);
626 gotit = TRUE;
627 }
628 mutex_exit(&ds->ds_lock);
629 return (gotit);
630 }
631
632 uint64_t
633 dsl_dataset_create_sync_dd(dsl_dir_t *dd, dsl_dataset_t *origin,
634 uint64_t flags, dmu_tx_t *tx)
635 {
636 dsl_pool_t *dp = dd->dd_pool;
637 dmu_buf_t *dbuf;
638 dsl_dataset_phys_t *dsphys;
639 uint64_t dsobj;
640 objset_t *mos = dp->dp_meta_objset;
641
642 if (origin == NULL)
643 origin = dp->dp_origin_snap;
644
645 ASSERT(origin == NULL || origin->ds_dir->dd_pool == dp);
646 ASSERT(origin == NULL || origin->ds_phys->ds_num_children > 0);
647 ASSERT(dmu_tx_is_syncing(tx));
648 ASSERT(dd->dd_phys->dd_head_dataset_obj == 0);
649
650 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0,
651 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx);
652 VERIFY0(dmu_bonus_hold(mos, dsobj, FTAG, &dbuf));
653 dmu_buf_will_dirty(dbuf, tx);
654 dsphys = dbuf->db_data;
655 bzero(dsphys, sizeof (dsl_dataset_phys_t));
656 dsphys->ds_dir_obj = dd->dd_object;
657 dsphys->ds_flags = flags;
658 dsphys->ds_fsid_guid = unique_create();
659 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid,
660 sizeof (dsphys->ds_guid));
661 dsphys->ds_snapnames_zapobj =
662 zap_create_norm(mos, U8_TEXTPREP_TOUPPER, DMU_OT_DSL_DS_SNAP_MAP,
663 DMU_OT_NONE, 0, tx);
664 dsphys->ds_creation_time = gethrestime_sec();
665 dsphys->ds_creation_txg = tx->tx_txg == TXG_INITIAL ? 1 : tx->tx_txg;
666
667 if (origin == NULL) {
668 dsphys->ds_deadlist_obj = dsl_deadlist_alloc(mos, tx);
669 } else {
670 dsl_dataset_t *ohds; /* head of the origin snapshot */
671
672 dsphys->ds_prev_snap_obj = origin->ds_object;
673 dsphys->ds_prev_snap_txg =
674 origin->ds_phys->ds_creation_txg;
675 dsphys->ds_referenced_bytes =
676 origin->ds_phys->ds_referenced_bytes;
677 dsphys->ds_compressed_bytes =
678 origin->ds_phys->ds_compressed_bytes;
679 dsphys->ds_uncompressed_bytes =
680 origin->ds_phys->ds_uncompressed_bytes;
681 dsphys->ds_bp = origin->ds_phys->ds_bp;
682 dsphys->ds_flags |= origin->ds_phys->ds_flags;
683
684 dmu_buf_will_dirty(origin->ds_dbuf, tx);
685 origin->ds_phys->ds_num_children++;
686
687 VERIFY0(dsl_dataset_hold_obj(dp,
688 origin->ds_dir->dd_phys->dd_head_dataset_obj, FTAG, &ohds));
689 dsphys->ds_deadlist_obj = dsl_deadlist_clone(&ohds->ds_deadlist,
690 dsphys->ds_prev_snap_txg, dsphys->ds_prev_snap_obj, tx);
691 dsl_dataset_rele(ohds, FTAG);
692
693 if (spa_version(dp->dp_spa) >= SPA_VERSION_NEXT_CLONES) {
694 if (origin->ds_phys->ds_next_clones_obj == 0) {
695 origin->ds_phys->ds_next_clones_obj =
696 zap_create(mos,
697 DMU_OT_NEXT_CLONES, DMU_OT_NONE, 0, tx);
698 }
699 VERIFY0(zap_add_int(mos,
700 origin->ds_phys->ds_next_clones_obj, dsobj, tx));
701 }
702
703 dmu_buf_will_dirty(dd->dd_dbuf, tx);
704 dd->dd_phys->dd_origin_obj = origin->ds_object;
705 if (spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) {
706 if (origin->ds_dir->dd_phys->dd_clones == 0) {
707 dmu_buf_will_dirty(origin->ds_dir->dd_dbuf, tx);
708 origin->ds_dir->dd_phys->dd_clones =
709 zap_create(mos,
710 DMU_OT_DSL_CLONES, DMU_OT_NONE, 0, tx);
711 }
712 VERIFY0(zap_add_int(mos,
713 origin->ds_dir->dd_phys->dd_clones, dsobj, tx));
714 }
715 }
716
717 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE)
718 dsphys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE;
719
720 dmu_buf_rele(dbuf, FTAG);
721
722 dmu_buf_will_dirty(dd->dd_dbuf, tx);
723 dd->dd_phys->dd_head_dataset_obj = dsobj;
724
725 return (dsobj);
726 }
727
728 static void
729 dsl_dataset_zero_zil(dsl_dataset_t *ds, dmu_tx_t *tx)
730 {
731 objset_t *os;
732
733 VERIFY0(dmu_objset_from_ds(ds, &os));
734 bzero(&os->os_zil_header, sizeof (os->os_zil_header));
735 dsl_dataset_dirty(ds, tx);
736 }
737
738 uint64_t
739 dsl_dataset_create_sync(dsl_dir_t *pdd, const char *lastname,
740 dsl_dataset_t *origin, uint64_t flags, cred_t *cr, dmu_tx_t *tx)
741 {
742 dsl_pool_t *dp = pdd->dd_pool;
743 uint64_t dsobj, ddobj;
744 dsl_dir_t *dd;
745
746 ASSERT(dmu_tx_is_syncing(tx));
747 ASSERT(lastname[0] != '@');
748
749 ddobj = dsl_dir_create_sync(dp, pdd, lastname, tx);
750 VERIFY0(dsl_dir_hold_obj(dp, ddobj, lastname, FTAG, &dd));
751
752 dsobj = dsl_dataset_create_sync_dd(dd, origin,
753 flags & ~DS_CREATE_FLAG_NODIRTY, tx);
754
755 dsl_deleg_set_create_perms(dd, tx, cr);
756
757 dsl_dir_rele(dd, FTAG);
758
759 /*
760 * If we are creating a clone, make sure we zero out any stale
761 * data from the origin snapshots zil header.
762 */
763 if (origin != NULL && !(flags & DS_CREATE_FLAG_NODIRTY)) {
764 dsl_dataset_t *ds;
765
766 VERIFY0(dsl_dataset_hold_obj(dp, dsobj, FTAG, &ds));
767 dsl_dataset_zero_zil(ds, tx);
768 dsl_dataset_rele(ds, FTAG);
769 }
770
771 return (dsobj);
772 }
773
774 /*
775 * The unique space in the head dataset can be calculated by subtracting
776 * the space used in the most recent snapshot, that is still being used
777 * in this file system, from the space currently in use. To figure out
778 * the space in the most recent snapshot still in use, we need to take
779 * the total space used in the snapshot and subtract out the space that
780 * has been freed up since the snapshot was taken.
781 */
782 void
783 dsl_dataset_recalc_head_uniq(dsl_dataset_t *ds)
784 {
785 uint64_t mrs_used;
786 uint64_t dlused, dlcomp, dluncomp;
787
788 ASSERT(!dsl_dataset_is_snapshot(ds));
789
790 if (ds->ds_phys->ds_prev_snap_obj != 0)
791 mrs_used = ds->ds_prev->ds_phys->ds_referenced_bytes;
792 else
793 mrs_used = 0;
794
795 dsl_deadlist_space(&ds->ds_deadlist, &dlused, &dlcomp, &dluncomp);
796
797 ASSERT3U(dlused, <=, mrs_used);
798 ds->ds_phys->ds_unique_bytes =
799 ds->ds_phys->ds_referenced_bytes - (mrs_used - dlused);
800
801 if (spa_version(ds->ds_dir->dd_pool->dp_spa) >=
802 SPA_VERSION_UNIQUE_ACCURATE)
803 ds->ds_phys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE;
804 }
805
806 void
807 dsl_dataset_remove_from_next_clones(dsl_dataset_t *ds, uint64_t obj,
808 dmu_tx_t *tx)
809 {
810 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
811 int err;
812 ASSERTV(uint64_t count);
813
814 ASSERT(ds->ds_phys->ds_num_children >= 2);
815 err = zap_remove_int(mos, ds->ds_phys->ds_next_clones_obj, obj, tx);
816 /*
817 * The err should not be ENOENT, but a bug in a previous version
818 * of the code could cause upgrade_clones_cb() to not set
819 * ds_next_snap_obj when it should, leading to a missing entry.
820 * If we knew that the pool was created after
821 * SPA_VERSION_NEXT_CLONES, we could assert that it isn't
822 * ENOENT. However, at least we can check that we don't have
823 * too many entries in the next_clones_obj even after failing to
824 * remove this one.
825 */
826 if (err != ENOENT)
827 VERIFY0(err);
828 ASSERT0(zap_count(mos, ds->ds_phys->ds_next_clones_obj,
829 &count));
830 ASSERT3U(count, <=, ds->ds_phys->ds_num_children - 2);
831 }
832
833
834 blkptr_t *
835 dsl_dataset_get_blkptr(dsl_dataset_t *ds)
836 {
837 return (&ds->ds_phys->ds_bp);
838 }
839
840 void
841 dsl_dataset_set_blkptr(dsl_dataset_t *ds, blkptr_t *bp, dmu_tx_t *tx)
842 {
843 ASSERT(dmu_tx_is_syncing(tx));
844 /* If it's the meta-objset, set dp_meta_rootbp */
845 if (ds == NULL) {
846 tx->tx_pool->dp_meta_rootbp = *bp;
847 } else {
848 dmu_buf_will_dirty(ds->ds_dbuf, tx);
849 ds->ds_phys->ds_bp = *bp;
850 }
851 }
852
853 spa_t *
854 dsl_dataset_get_spa(dsl_dataset_t *ds)
855 {
856 return (ds->ds_dir->dd_pool->dp_spa);
857 }
858
859 void
860 dsl_dataset_dirty(dsl_dataset_t *ds, dmu_tx_t *tx)
861 {
862 dsl_pool_t *dp;
863
864 if (ds == NULL) /* this is the meta-objset */
865 return;
866
867 ASSERT(ds->ds_objset != NULL);
868
869 if (ds->ds_phys->ds_next_snap_obj != 0)
870 panic("dirtying snapshot!");
871
872 dp = ds->ds_dir->dd_pool;
873
874 if (txg_list_add(&dp->dp_dirty_datasets, ds, tx->tx_txg)) {
875 /* up the hold count until we can be written out */
876 dmu_buf_add_ref(ds->ds_dbuf, ds);
877 }
878 }
879
880 boolean_t
881 dsl_dataset_is_dirty(dsl_dataset_t *ds)
882 {
883 int t;
884
885 for (t = 0; t < TXG_SIZE; t++) {
886 if (txg_list_member(&ds->ds_dir->dd_pool->dp_dirty_datasets,
887 ds, t))
888 return (B_TRUE);
889 }
890 return (B_FALSE);
891 }
892
893 static int
894 dsl_dataset_snapshot_reserve_space(dsl_dataset_t *ds, dmu_tx_t *tx)
895 {
896 uint64_t asize;
897
898 if (!dmu_tx_is_syncing(tx))
899 return (0);
900
901 /*
902 * If there's an fs-only reservation, any blocks that might become
903 * owned by the snapshot dataset must be accommodated by space
904 * outside of the reservation.
905 */
906 ASSERT(ds->ds_reserved == 0 || DS_UNIQUE_IS_ACCURATE(ds));
907 asize = MIN(ds->ds_phys->ds_unique_bytes, ds->ds_reserved);
908 if (asize > dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE))
909 return (SET_ERROR(ENOSPC));
910
911 /*
912 * Propagate any reserved space for this snapshot to other
913 * snapshot checks in this sync group.
914 */
915 if (asize > 0)
916 dsl_dir_willuse_space(ds->ds_dir, asize, tx);
917
918 return (0);
919 }
920
921 typedef struct dsl_dataset_snapshot_arg {
922 nvlist_t *ddsa_snaps;
923 nvlist_t *ddsa_props;
924 nvlist_t *ddsa_errors;
925 } dsl_dataset_snapshot_arg_t;
926
927 int
928 dsl_dataset_snapshot_check_impl(dsl_dataset_t *ds, const char *snapname,
929 dmu_tx_t *tx, boolean_t recv)
930 {
931 int error;
932 uint64_t value;
933
934 ds->ds_trysnap_txg = tx->tx_txg;
935
936 if (!dmu_tx_is_syncing(tx))
937 return (0);
938
939 /*
940 * We don't allow multiple snapshots of the same txg. If there
941 * is already one, try again.
942 */
943 if (ds->ds_phys->ds_prev_snap_txg >= tx->tx_txg)
944 return (SET_ERROR(EAGAIN));
945
946 /*
947 * Check for conflicting snapshot name.
948 */
949 error = dsl_dataset_snap_lookup(ds, snapname, &value);
950 if (error == 0)
951 return (SET_ERROR(EEXIST));
952 if (error != ENOENT)
953 return (error);
954
955 /*
956 * We don't allow taking snapshots of inconsistent datasets, such as
957 * those into which we are currently receiving. However, if we are
958 * creating this snapshot as part of a receive, this check will be
959 * executed atomically with respect to the completion of the receive
960 * itself but prior to the clearing of DS_FLAG_INCONSISTENT; in this
961 * case we ignore this, knowing it will be fixed up for us shortly in
962 * dmu_recv_end_sync().
963 */
964 if (!recv && DS_IS_INCONSISTENT(ds))
965 return (SET_ERROR(EBUSY));
966
967 error = dsl_dataset_snapshot_reserve_space(ds, tx);
968 if (error != 0)
969 return (error);
970
971 return (0);
972 }
973
974 static int
975 dsl_dataset_snapshot_check(void *arg, dmu_tx_t *tx)
976 {
977 dsl_dataset_snapshot_arg_t *ddsa = arg;
978 dsl_pool_t *dp = dmu_tx_pool(tx);
979 nvpair_t *pair;
980 int rv = 0;
981
982 for (pair = nvlist_next_nvpair(ddsa->ddsa_snaps, NULL);
983 pair != NULL; pair = nvlist_next_nvpair(ddsa->ddsa_snaps, pair)) {
984 int error = 0;
985 dsl_dataset_t *ds;
986 char *name, *atp;
987 char dsname[MAXNAMELEN];
988
989 name = nvpair_name(pair);
990 if (strlen(name) >= MAXNAMELEN)
991 error = SET_ERROR(ENAMETOOLONG);
992 if (error == 0) {
993 atp = strchr(name, '@');
994 if (atp == NULL)
995 error = SET_ERROR(EINVAL);
996 if (error == 0)
997 (void) strlcpy(dsname, name, atp - name + 1);
998 }
999 if (error == 0)
1000 error = dsl_dataset_hold(dp, dsname, FTAG, &ds);
1001 if (error == 0) {
1002 error = dsl_dataset_snapshot_check_impl(ds,
1003 atp + 1, tx, B_FALSE);
1004 dsl_dataset_rele(ds, FTAG);
1005 }
1006
1007 if (error != 0) {
1008 if (ddsa->ddsa_errors != NULL) {
1009 fnvlist_add_int32(ddsa->ddsa_errors,
1010 name, error);
1011 }
1012 rv = error;
1013 }
1014 }
1015 return (rv);
1016 }
1017
1018 void
1019 dsl_dataset_snapshot_sync_impl(dsl_dataset_t *ds, const char *snapname,
1020 dmu_tx_t *tx)
1021 {
1022 dsl_pool_t *dp = ds->ds_dir->dd_pool;
1023 dmu_buf_t *dbuf;
1024 dsl_dataset_phys_t *dsphys;
1025 uint64_t dsobj, crtxg;
1026 objset_t *mos = dp->dp_meta_objset;
1027 ASSERTV(static zil_header_t zero_zil);
1028 ASSERTV(objset_t *os);
1029
1030 ASSERT(RRW_WRITE_HELD(&dp->dp_config_rwlock));
1031
1032 /*
1033 * If we are on an old pool, the zil must not be active, in which
1034 * case it will be zeroed. Usually zil_suspend() accomplishes this.
1035 */
1036 ASSERT(spa_version(dmu_tx_pool(tx)->dp_spa) >= SPA_VERSION_FAST_SNAP ||
1037 dmu_objset_from_ds(ds, &os) != 0 ||
1038 bcmp(&os->os_phys->os_zil_header, &zero_zil,
1039 sizeof (zero_zil)) == 0);
1040
1041
1042 /*
1043 * The origin's ds_creation_txg has to be < TXG_INITIAL
1044 */
1045 if (strcmp(snapname, ORIGIN_DIR_NAME) == 0)
1046 crtxg = 1;
1047 else
1048 crtxg = tx->tx_txg;
1049
1050 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0,
1051 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx);
1052 VERIFY0(dmu_bonus_hold(mos, dsobj, FTAG, &dbuf));
1053 dmu_buf_will_dirty(dbuf, tx);
1054 dsphys = dbuf->db_data;
1055 bzero(dsphys, sizeof (dsl_dataset_phys_t));
1056 dsphys->ds_dir_obj = ds->ds_dir->dd_object;
1057 dsphys->ds_fsid_guid = unique_create();
1058 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid,
1059 sizeof (dsphys->ds_guid));
1060 dsphys->ds_prev_snap_obj = ds->ds_phys->ds_prev_snap_obj;
1061 dsphys->ds_prev_snap_txg = ds->ds_phys->ds_prev_snap_txg;
1062 dsphys->ds_next_snap_obj = ds->ds_object;
1063 dsphys->ds_num_children = 1;
1064 dsphys->ds_creation_time = gethrestime_sec();
1065 dsphys->ds_creation_txg = crtxg;
1066 dsphys->ds_deadlist_obj = ds->ds_phys->ds_deadlist_obj;
1067 dsphys->ds_referenced_bytes = ds->ds_phys->ds_referenced_bytes;
1068 dsphys->ds_compressed_bytes = ds->ds_phys->ds_compressed_bytes;
1069 dsphys->ds_uncompressed_bytes = ds->ds_phys->ds_uncompressed_bytes;
1070 dsphys->ds_flags = ds->ds_phys->ds_flags;
1071 dsphys->ds_bp = ds->ds_phys->ds_bp;
1072 dmu_buf_rele(dbuf, FTAG);
1073
1074 ASSERT3U(ds->ds_prev != 0, ==, ds->ds_phys->ds_prev_snap_obj != 0);
1075 if (ds->ds_prev) {
1076 uint64_t next_clones_obj =
1077 ds->ds_prev->ds_phys->ds_next_clones_obj;
1078 ASSERT(ds->ds_prev->ds_phys->ds_next_snap_obj ==
1079 ds->ds_object ||
1080 ds->ds_prev->ds_phys->ds_num_children > 1);
1081 if (ds->ds_prev->ds_phys->ds_next_snap_obj == ds->ds_object) {
1082 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx);
1083 ASSERT3U(ds->ds_phys->ds_prev_snap_txg, ==,
1084 ds->ds_prev->ds_phys->ds_creation_txg);
1085 ds->ds_prev->ds_phys->ds_next_snap_obj = dsobj;
1086 } else if (next_clones_obj != 0) {
1087 dsl_dataset_remove_from_next_clones(ds->ds_prev,
1088 dsphys->ds_next_snap_obj, tx);
1089 VERIFY0(zap_add_int(mos,
1090 next_clones_obj, dsobj, tx));
1091 }
1092 }
1093
1094 /*
1095 * If we have a reference-reservation on this dataset, we will
1096 * need to increase the amount of refreservation being charged
1097 * since our unique space is going to zero.
1098 */
1099 if (ds->ds_reserved) {
1100 int64_t delta;
1101 ASSERT(DS_UNIQUE_IS_ACCURATE(ds));
1102 delta = MIN(ds->ds_phys->ds_unique_bytes, ds->ds_reserved);
1103 dsl_dir_diduse_space(ds->ds_dir, DD_USED_REFRSRV,
1104 delta, 0, 0, tx);
1105 }
1106
1107 dmu_buf_will_dirty(ds->ds_dbuf, tx);
1108 ds->ds_phys->ds_deadlist_obj = dsl_deadlist_clone(&ds->ds_deadlist,
1109 UINT64_MAX, ds->ds_phys->ds_prev_snap_obj, tx);
1110 dsl_deadlist_close(&ds->ds_deadlist);
1111 dsl_deadlist_open(&ds->ds_deadlist, mos, ds->ds_phys->ds_deadlist_obj);
1112 dsl_deadlist_add_key(&ds->ds_deadlist,
1113 ds->ds_phys->ds_prev_snap_txg, tx);
1114
1115 ASSERT3U(ds->ds_phys->ds_prev_snap_txg, <, tx->tx_txg);
1116 ds->ds_phys->ds_prev_snap_obj = dsobj;
1117 ds->ds_phys->ds_prev_snap_txg = crtxg;
1118 ds->ds_phys->ds_unique_bytes = 0;
1119 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE)
1120 ds->ds_phys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE;
1121
1122 VERIFY0(zap_add(mos, ds->ds_phys->ds_snapnames_zapobj,
1123 snapname, 8, 1, &dsobj, tx));
1124
1125 if (ds->ds_prev)
1126 dsl_dataset_rele(ds->ds_prev, ds);
1127 VERIFY0(dsl_dataset_hold_obj(dp,
1128 ds->ds_phys->ds_prev_snap_obj, ds, &ds->ds_prev));
1129
1130 dsl_scan_ds_snapshotted(ds, tx);
1131
1132 dsl_dir_snap_cmtime_update(ds->ds_dir);
1133
1134 spa_history_log_internal_ds(ds->ds_prev, "snapshot", tx, "");
1135 }
1136
1137 static void
1138 dsl_dataset_snapshot_sync(void *arg, dmu_tx_t *tx)
1139 {
1140 dsl_dataset_snapshot_arg_t *ddsa = arg;
1141 dsl_pool_t *dp = dmu_tx_pool(tx);
1142 nvpair_t *pair;
1143
1144 for (pair = nvlist_next_nvpair(ddsa->ddsa_snaps, NULL);
1145 pair != NULL; pair = nvlist_next_nvpair(ddsa->ddsa_snaps, pair)) {
1146 dsl_dataset_t *ds;
1147 char *name, *atp;
1148 char dsname[MAXNAMELEN];
1149
1150 name = nvpair_name(pair);
1151 atp = strchr(name, '@');
1152 (void) strlcpy(dsname, name, atp - name + 1);
1153 VERIFY0(dsl_dataset_hold(dp, dsname, FTAG, &ds));
1154
1155 dsl_dataset_snapshot_sync_impl(ds, atp + 1, tx);
1156 if (ddsa->ddsa_props != NULL) {
1157 dsl_props_set_sync_impl(ds->ds_prev,
1158 ZPROP_SRC_LOCAL, ddsa->ddsa_props, tx);
1159 }
1160 dsl_dataset_rele(ds, FTAG);
1161 }
1162 }
1163
1164 /*
1165 * The snapshots must all be in the same pool.
1166 * All-or-nothing: if there are any failures, nothing will be modified.
1167 */
1168 int
1169 dsl_dataset_snapshot(nvlist_t *snaps, nvlist_t *props, nvlist_t *errors)
1170 {
1171 dsl_dataset_snapshot_arg_t ddsa;
1172 nvpair_t *pair;
1173 boolean_t needsuspend;
1174 int error;
1175 spa_t *spa;
1176 char *firstname;
1177 nvlist_t *suspended = NULL;
1178
1179 pair = nvlist_next_nvpair(snaps, NULL);
1180 if (pair == NULL)
1181 return (0);
1182 firstname = nvpair_name(pair);
1183
1184 error = spa_open(firstname, &spa, FTAG);
1185 if (error != 0)
1186 return (error);
1187 needsuspend = (spa_version(spa) < SPA_VERSION_FAST_SNAP);
1188 spa_close(spa, FTAG);
1189
1190 if (needsuspend) {
1191 suspended = fnvlist_alloc();
1192 for (pair = nvlist_next_nvpair(snaps, NULL); pair != NULL;
1193 pair = nvlist_next_nvpair(snaps, pair)) {
1194 char fsname[MAXNAMELEN];
1195 char *snapname = nvpair_name(pair);
1196 char *atp;
1197 void *cookie;
1198
1199 atp = strchr(snapname, '@');
1200 if (atp == NULL) {
1201 error = SET_ERROR(EINVAL);
1202 break;
1203 }
1204 (void) strlcpy(fsname, snapname, atp - snapname + 1);
1205
1206 error = zil_suspend(fsname, &cookie);
1207 if (error != 0)
1208 break;
1209 fnvlist_add_uint64(suspended, fsname,
1210 (uintptr_t)cookie);
1211 }
1212 }
1213
1214 ddsa.ddsa_snaps = snaps;
1215 ddsa.ddsa_props = props;
1216 ddsa.ddsa_errors = errors;
1217
1218 if (error == 0) {
1219 error = dsl_sync_task(firstname, dsl_dataset_snapshot_check,
1220 dsl_dataset_snapshot_sync, &ddsa,
1221 fnvlist_num_pairs(snaps) * 3);
1222 }
1223
1224 if (suspended != NULL) {
1225 for (pair = nvlist_next_nvpair(suspended, NULL); pair != NULL;
1226 pair = nvlist_next_nvpair(suspended, pair)) {
1227 zil_resume((void *)(uintptr_t)
1228 fnvpair_value_uint64(pair));
1229 }
1230 fnvlist_free(suspended);
1231 }
1232
1233 #ifdef _KERNEL
1234 if (error == 0) {
1235 for (pair = nvlist_next_nvpair(snaps, NULL); pair != NULL;
1236 pair = nvlist_next_nvpair(snaps, pair)) {
1237 char *snapname = nvpair_name(pair);
1238 zvol_create_minors(snapname);
1239 }
1240 }
1241 #endif
1242
1243 return (error);
1244 }
1245
1246 typedef struct dsl_dataset_snapshot_tmp_arg {
1247 const char *ddsta_fsname;
1248 const char *ddsta_snapname;
1249 minor_t ddsta_cleanup_minor;
1250 const char *ddsta_htag;
1251 } dsl_dataset_snapshot_tmp_arg_t;
1252
1253 static int
1254 dsl_dataset_snapshot_tmp_check(void *arg, dmu_tx_t *tx)
1255 {
1256 dsl_dataset_snapshot_tmp_arg_t *ddsta = arg;
1257 dsl_pool_t *dp = dmu_tx_pool(tx);
1258 dsl_dataset_t *ds;
1259 int error;
1260
1261 error = dsl_dataset_hold(dp, ddsta->ddsta_fsname, FTAG, &ds);
1262 if (error != 0)
1263 return (error);
1264
1265 error = dsl_dataset_snapshot_check_impl(ds, ddsta->ddsta_snapname,
1266 tx, B_FALSE);
1267 if (error != 0) {
1268 dsl_dataset_rele(ds, FTAG);
1269 return (error);
1270 }
1271
1272 if (spa_version(dp->dp_spa) < SPA_VERSION_USERREFS) {
1273 dsl_dataset_rele(ds, FTAG);
1274 return (SET_ERROR(ENOTSUP));
1275 }
1276 error = dsl_dataset_user_hold_check_one(NULL, ddsta->ddsta_htag,
1277 B_TRUE, tx);
1278 if (error != 0) {
1279 dsl_dataset_rele(ds, FTAG);
1280 return (error);
1281 }
1282
1283 dsl_dataset_rele(ds, FTAG);
1284 return (0);
1285 }
1286
1287 static void
1288 dsl_dataset_snapshot_tmp_sync(void *arg, dmu_tx_t *tx)
1289 {
1290 dsl_dataset_snapshot_tmp_arg_t *ddsta = arg;
1291 dsl_pool_t *dp = dmu_tx_pool(tx);
1292 dsl_dataset_t *ds;
1293
1294 VERIFY0(dsl_dataset_hold(dp, ddsta->ddsta_fsname, FTAG, &ds));
1295
1296 dsl_dataset_snapshot_sync_impl(ds, ddsta->ddsta_snapname, tx);
1297 dsl_dataset_user_hold_sync_one(ds->ds_prev, ddsta->ddsta_htag,
1298 ddsta->ddsta_cleanup_minor, gethrestime_sec(), tx);
1299 dsl_destroy_snapshot_sync_impl(ds->ds_prev, B_TRUE, tx);
1300
1301 dsl_dataset_rele(ds, FTAG);
1302 }
1303
1304 int
1305 dsl_dataset_snapshot_tmp(const char *fsname, const char *snapname,
1306 minor_t cleanup_minor, const char *htag)
1307 {
1308 dsl_dataset_snapshot_tmp_arg_t ddsta;
1309 int error;
1310 spa_t *spa;
1311 boolean_t needsuspend;
1312 void *cookie;
1313
1314 ddsta.ddsta_fsname = fsname;
1315 ddsta.ddsta_snapname = snapname;
1316 ddsta.ddsta_cleanup_minor = cleanup_minor;
1317 ddsta.ddsta_htag = htag;
1318
1319 error = spa_open(fsname, &spa, FTAG);
1320 if (error != 0)
1321 return (error);
1322 needsuspend = (spa_version(spa) < SPA_VERSION_FAST_SNAP);
1323 spa_close(spa, FTAG);
1324
1325 if (needsuspend) {
1326 error = zil_suspend(fsname, &cookie);
1327 if (error != 0)
1328 return (error);
1329 }
1330
1331 error = dsl_sync_task(fsname, dsl_dataset_snapshot_tmp_check,
1332 dsl_dataset_snapshot_tmp_sync, &ddsta, 3);
1333
1334 if (needsuspend)
1335 zil_resume(cookie);
1336 return (error);
1337 }
1338
1339
1340 void
1341 dsl_dataset_sync(dsl_dataset_t *ds, zio_t *zio, dmu_tx_t *tx)
1342 {
1343 ASSERT(dmu_tx_is_syncing(tx));
1344 ASSERT(ds->ds_objset != NULL);
1345 ASSERT(ds->ds_phys->ds_next_snap_obj == 0);
1346
1347 /*
1348 * in case we had to change ds_fsid_guid when we opened it,
1349 * sync it out now.
1350 */
1351 dmu_buf_will_dirty(ds->ds_dbuf, tx);
1352 ds->ds_phys->ds_fsid_guid = ds->ds_fsid_guid;
1353
1354 dmu_objset_sync(ds->ds_objset, zio, tx);
1355 }
1356
1357 static void
1358 get_clones_stat(dsl_dataset_t *ds, nvlist_t *nv)
1359 {
1360 uint64_t count = 0;
1361 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
1362 zap_cursor_t zc;
1363 zap_attribute_t za;
1364 nvlist_t *propval = fnvlist_alloc();
1365 nvlist_t *val = fnvlist_alloc();
1366
1367 ASSERT(dsl_pool_config_held(ds->ds_dir->dd_pool));
1368
1369 /*
1370 * There may be missing entries in ds_next_clones_obj
1371 * due to a bug in a previous version of the code.
1372 * Only trust it if it has the right number of entries.
1373 */
1374 if (ds->ds_phys->ds_next_clones_obj != 0) {
1375 VERIFY0(zap_count(mos, ds->ds_phys->ds_next_clones_obj,
1376 &count));
1377 }
1378 if (count != ds->ds_phys->ds_num_children - 1)
1379 goto fail;
1380 for (zap_cursor_init(&zc, mos, ds->ds_phys->ds_next_clones_obj);
1381 zap_cursor_retrieve(&zc, &za) == 0;
1382 zap_cursor_advance(&zc)) {
1383 dsl_dataset_t *clone;
1384 char buf[ZFS_MAXNAMELEN];
1385 VERIFY0(dsl_dataset_hold_obj(ds->ds_dir->dd_pool,
1386 za.za_first_integer, FTAG, &clone));
1387 dsl_dir_name(clone->ds_dir, buf);
1388 fnvlist_add_boolean(val, buf);
1389 dsl_dataset_rele(clone, FTAG);
1390 }
1391 zap_cursor_fini(&zc);
1392 fnvlist_add_nvlist(propval, ZPROP_VALUE, val);
1393 fnvlist_add_nvlist(nv, zfs_prop_to_name(ZFS_PROP_CLONES), propval);
1394 fail:
1395 nvlist_free(val);
1396 nvlist_free(propval);
1397 }
1398
1399 void
1400 dsl_dataset_stats(dsl_dataset_t *ds, nvlist_t *nv)
1401 {
1402 uint64_t refd, avail, uobjs, aobjs, ratio;
1403 ASSERTV(dsl_pool_t *dp = ds->ds_dir->dd_pool);
1404
1405 ASSERT(dsl_pool_config_held(dp));
1406
1407 ratio = ds->ds_phys->ds_compressed_bytes == 0 ? 100 :
1408 (ds->ds_phys->ds_uncompressed_bytes * 100 /
1409 ds->ds_phys->ds_compressed_bytes);
1410
1411 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFRATIO, ratio);
1412 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_LOGICALREFERENCED,
1413 ds->ds_phys->ds_uncompressed_bytes);
1414
1415 if (dsl_dataset_is_snapshot(ds)) {
1416 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_COMPRESSRATIO, ratio);
1417 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USED,
1418 ds->ds_phys->ds_unique_bytes);
1419 get_clones_stat(ds, nv);
1420 } else {
1421 dsl_dir_stats(ds->ds_dir, nv);
1422 }
1423
1424 dsl_dataset_space(ds, &refd, &avail, &uobjs, &aobjs);
1425 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_AVAILABLE, avail);
1426 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFERENCED, refd);
1427
1428 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATION,
1429 ds->ds_phys->ds_creation_time);
1430 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATETXG,
1431 ds->ds_phys->ds_creation_txg);
1432 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFQUOTA,
1433 ds->ds_quota);
1434 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFRESERVATION,
1435 ds->ds_reserved);
1436 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_GUID,
1437 ds->ds_phys->ds_guid);
1438 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_UNIQUE,
1439 ds->ds_phys->ds_unique_bytes);
1440 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_OBJSETID,
1441 ds->ds_object);
1442 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USERREFS,
1443 ds->ds_userrefs);
1444 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_DEFER_DESTROY,
1445 DS_IS_DEFER_DESTROY(ds) ? 1 : 0);
1446
1447 if (ds->ds_phys->ds_prev_snap_obj != 0) {
1448 uint64_t written, comp, uncomp;
1449 dsl_pool_t *dp = ds->ds_dir->dd_pool;
1450 dsl_dataset_t *prev;
1451 int err;
1452
1453 err = dsl_dataset_hold_obj(dp,
1454 ds->ds_phys->ds_prev_snap_obj, FTAG, &prev);
1455 if (err == 0) {
1456 err = dsl_dataset_space_written(prev, ds, &written,
1457 &comp, &uncomp);
1458 dsl_dataset_rele(prev, FTAG);
1459 if (err == 0) {
1460 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_WRITTEN,
1461 written);
1462 }
1463 }
1464 }
1465
1466 }
1467
1468 void
1469 dsl_dataset_fast_stat(dsl_dataset_t *ds, dmu_objset_stats_t *stat)
1470 {
1471 dsl_pool_t *dp = ds->ds_dir->dd_pool;
1472 ASSERT(dsl_pool_config_held(dp));
1473
1474 stat->dds_creation_txg = ds->ds_phys->ds_creation_txg;
1475 stat->dds_inconsistent = ds->ds_phys->ds_flags & DS_FLAG_INCONSISTENT;
1476 stat->dds_guid = ds->ds_phys->ds_guid;
1477 stat->dds_origin[0] = '\0';
1478 if (dsl_dataset_is_snapshot(ds)) {
1479 stat->dds_is_snapshot = B_TRUE;
1480 stat->dds_num_clones = ds->ds_phys->ds_num_children - 1;
1481 } else {
1482 stat->dds_is_snapshot = B_FALSE;
1483 stat->dds_num_clones = 0;
1484
1485 if (dsl_dir_is_clone(ds->ds_dir)) {
1486 dsl_dataset_t *ods;
1487
1488 VERIFY0(dsl_dataset_hold_obj(dp,
1489 ds->ds_dir->dd_phys->dd_origin_obj, FTAG, &ods));
1490 dsl_dataset_name(ods, stat->dds_origin);
1491 dsl_dataset_rele(ods, FTAG);
1492 }
1493 }
1494 }
1495
1496 uint64_t
1497 dsl_dataset_fsid_guid(dsl_dataset_t *ds)
1498 {
1499 return (ds->ds_fsid_guid);
1500 }
1501
1502 void
1503 dsl_dataset_space(dsl_dataset_t *ds,
1504 uint64_t *refdbytesp, uint64_t *availbytesp,
1505 uint64_t *usedobjsp, uint64_t *availobjsp)
1506 {
1507 *refdbytesp = ds->ds_phys->ds_referenced_bytes;
1508 *availbytesp = dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE);
1509 if (ds->ds_reserved > ds->ds_phys->ds_unique_bytes)
1510 *availbytesp += ds->ds_reserved - ds->ds_phys->ds_unique_bytes;
1511 if (ds->ds_quota != 0) {
1512 /*
1513 * Adjust available bytes according to refquota
1514 */
1515 if (*refdbytesp < ds->ds_quota)
1516 *availbytesp = MIN(*availbytesp,
1517 ds->ds_quota - *refdbytesp);
1518 else
1519 *availbytesp = 0;
1520 }
1521 *usedobjsp = ds->ds_phys->ds_bp.blk_fill;
1522 *availobjsp = DN_MAX_OBJECT - *usedobjsp;
1523 }
1524
1525 boolean_t
1526 dsl_dataset_modified_since_snap(dsl_dataset_t *ds, dsl_dataset_t *snap)
1527 {
1528 ASSERT(dsl_pool_config_held(ds->ds_dir->dd_pool));
1529 if (snap == NULL)
1530 return (B_FALSE);
1531 if (ds->ds_phys->ds_bp.blk_birth >
1532 snap->ds_phys->ds_creation_txg) {
1533 objset_t *os, *os_snap;
1534 /*
1535 * It may be that only the ZIL differs, because it was
1536 * reset in the head. Don't count that as being
1537 * modified.
1538 */
1539 if (dmu_objset_from_ds(ds, &os) != 0)
1540 return (B_TRUE);
1541 if (dmu_objset_from_ds(snap, &os_snap) != 0)
1542 return (B_TRUE);
1543 return (bcmp(&os->os_phys->os_meta_dnode,
1544 &os_snap->os_phys->os_meta_dnode,
1545 sizeof (os->os_phys->os_meta_dnode)) != 0);
1546 }
1547 return (B_FALSE);
1548 }
1549
1550 typedef struct dsl_dataset_rename_snapshot_arg {
1551 const char *ddrsa_fsname;
1552 const char *ddrsa_oldsnapname;
1553 const char *ddrsa_newsnapname;
1554 boolean_t ddrsa_recursive;
1555 dmu_tx_t *ddrsa_tx;
1556 } dsl_dataset_rename_snapshot_arg_t;
1557
1558 /* ARGSUSED */
1559 static int
1560 dsl_dataset_rename_snapshot_check_impl(dsl_pool_t *dp,
1561 dsl_dataset_t *hds, void *arg)
1562 {
1563 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg;
1564 int error;
1565 uint64_t val;
1566
1567 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_oldsnapname, &val);
1568 if (error != 0) {
1569 /* ignore nonexistent snapshots */
1570 return (error == ENOENT ? 0 : error);
1571 }
1572
1573 /* new name should not exist */
1574 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_newsnapname, &val);
1575 if (error == 0)
1576 error = SET_ERROR(EEXIST);
1577 else if (error == ENOENT)
1578 error = 0;
1579
1580 /* dataset name + 1 for the "@" + the new snapshot name must fit */
1581 if (dsl_dir_namelen(hds->ds_dir) + 1 +
1582 strlen(ddrsa->ddrsa_newsnapname) >= MAXNAMELEN)
1583 error = SET_ERROR(ENAMETOOLONG);
1584
1585 return (error);
1586 }
1587
1588 static int
1589 dsl_dataset_rename_snapshot_check(void *arg, dmu_tx_t *tx)
1590 {
1591 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg;
1592 dsl_pool_t *dp = dmu_tx_pool(tx);
1593 dsl_dataset_t *hds;
1594 int error;
1595
1596 error = dsl_dataset_hold(dp, ddrsa->ddrsa_fsname, FTAG, &hds);
1597 if (error != 0)
1598 return (error);
1599
1600 if (ddrsa->ddrsa_recursive) {
1601 error = dmu_objset_find_dp(dp, hds->ds_dir->dd_object,
1602 dsl_dataset_rename_snapshot_check_impl, ddrsa,
1603 DS_FIND_CHILDREN);
1604 } else {
1605 error = dsl_dataset_rename_snapshot_check_impl(dp, hds, ddrsa);
1606 }
1607 dsl_dataset_rele(hds, FTAG);
1608 return (error);
1609 }
1610
1611 static int
1612 dsl_dataset_rename_snapshot_sync_impl(dsl_pool_t *dp,
1613 dsl_dataset_t *hds, void *arg)
1614 {
1615 #ifdef _KERNEL
1616 char *oldname, *newname;
1617 #endif
1618 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg;
1619 dsl_dataset_t *ds;
1620 uint64_t val;
1621 dmu_tx_t *tx = ddrsa->ddrsa_tx;
1622 int error;
1623
1624 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_oldsnapname, &val);
1625 ASSERT(error == 0 || error == ENOENT);
1626 if (error == ENOENT) {
1627 /* ignore nonexistent snapshots */
1628 return (0);
1629 }
1630
1631 VERIFY0(dsl_dataset_hold_obj(dp, val, FTAG, &ds));
1632
1633 /* log before we change the name */
1634 spa_history_log_internal_ds(ds, "rename", tx,
1635 "-> @%s", ddrsa->ddrsa_newsnapname);
1636
1637 VERIFY0(dsl_dataset_snap_remove(hds, ddrsa->ddrsa_oldsnapname, tx));
1638 mutex_enter(&ds->ds_lock);
1639 (void) strcpy(ds->ds_snapname, ddrsa->ddrsa_newsnapname);
1640 mutex_exit(&ds->ds_lock);
1641 VERIFY0(zap_add(dp->dp_meta_objset, hds->ds_phys->ds_snapnames_zapobj,
1642 ds->ds_snapname, 8, 1, &ds->ds_object, tx));
1643
1644 #ifdef _KERNEL
1645 oldname = kmem_alloc(MAXPATHLEN, KM_PUSHPAGE);
1646 newname = kmem_alloc(MAXPATHLEN, KM_PUSHPAGE);
1647 snprintf(oldname, MAXPATHLEN, "%s@%s", ddrsa->ddrsa_fsname,
1648 ddrsa->ddrsa_oldsnapname);
1649 snprintf(newname, MAXPATHLEN, "%s@%s", ddrsa->ddrsa_fsname,
1650 ddrsa->ddrsa_newsnapname);
1651 zvol_rename_minors(oldname, newname);
1652 kmem_free(newname, MAXPATHLEN);
1653 kmem_free(oldname, MAXPATHLEN);
1654 #endif
1655
1656 dsl_dataset_rele(ds, FTAG);
1657 return (0);
1658 }
1659
1660 static void
1661 dsl_dataset_rename_snapshot_sync(void *arg, dmu_tx_t *tx)
1662 {
1663 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg;
1664 dsl_pool_t *dp = dmu_tx_pool(tx);
1665 dsl_dataset_t *hds;
1666
1667 VERIFY0(dsl_dataset_hold(dp, ddrsa->ddrsa_fsname, FTAG, &hds));
1668 ddrsa->ddrsa_tx = tx;
1669 if (ddrsa->ddrsa_recursive) {
1670 VERIFY0(dmu_objset_find_dp(dp, hds->ds_dir->dd_object,
1671 dsl_dataset_rename_snapshot_sync_impl, ddrsa,
1672 DS_FIND_CHILDREN));
1673 } else {
1674 VERIFY0(dsl_dataset_rename_snapshot_sync_impl(dp, hds, ddrsa));
1675 }
1676 dsl_dataset_rele(hds, FTAG);
1677 }
1678
1679 int
1680 dsl_dataset_rename_snapshot(const char *fsname,
1681 const char *oldsnapname, const char *newsnapname, boolean_t recursive)
1682 {
1683 dsl_dataset_rename_snapshot_arg_t ddrsa;
1684
1685 ddrsa.ddrsa_fsname = fsname;
1686 ddrsa.ddrsa_oldsnapname = oldsnapname;
1687 ddrsa.ddrsa_newsnapname = newsnapname;
1688 ddrsa.ddrsa_recursive = recursive;
1689
1690 return (dsl_sync_task(fsname, dsl_dataset_rename_snapshot_check,
1691 dsl_dataset_rename_snapshot_sync, &ddrsa, 1));
1692 }
1693
1694 /*
1695 * If we're doing an ownership handoff, we need to make sure that there is
1696 * only one long hold on the dataset. We're not allowed to change anything here
1697 * so we don't permanently release the long hold or regular hold here. We want
1698 * to do this only when syncing to avoid the dataset unexpectedly going away
1699 * when we release the long hold.
1700 */
1701 static int
1702 dsl_dataset_handoff_check(dsl_dataset_t *ds, void *owner, dmu_tx_t *tx)
1703 {
1704 boolean_t held;
1705
1706 if (!dmu_tx_is_syncing(tx))
1707 return (0);
1708
1709 if (owner != NULL) {
1710 VERIFY3P(ds->ds_owner, ==, owner);
1711 dsl_dataset_long_rele(ds, owner);
1712 }
1713
1714 held = dsl_dataset_long_held(ds);
1715
1716 if (owner != NULL)
1717 dsl_dataset_long_hold(ds, owner);
1718
1719 if (held)
1720 return (SET_ERROR(EBUSY));
1721
1722 return (0);
1723 }
1724
1725 typedef struct dsl_dataset_rollback_arg {
1726 const char *ddra_fsname;
1727 void *ddra_owner;
1728 nvlist_t *ddra_result;
1729 } dsl_dataset_rollback_arg_t;
1730
1731 static int
1732 dsl_dataset_rollback_check(void *arg, dmu_tx_t *tx)
1733 {
1734 dsl_dataset_rollback_arg_t *ddra = arg;
1735 dsl_pool_t *dp = dmu_tx_pool(tx);
1736 dsl_dataset_t *ds;
1737 int64_t unused_refres_delta;
1738 int error;
1739
1740 error = dsl_dataset_hold(dp, ddra->ddra_fsname, FTAG, &ds);
1741 if (error != 0)
1742 return (error);
1743
1744 /* must not be a snapshot */
1745 if (dsl_dataset_is_snapshot(ds)) {
1746 dsl_dataset_rele(ds, FTAG);
1747 return (SET_ERROR(EINVAL));
1748 }
1749
1750 /* must have a most recent snapshot */
1751 if (ds->ds_phys->ds_prev_snap_txg < TXG_INITIAL) {
1752 dsl_dataset_rele(ds, FTAG);
1753 return (SET_ERROR(EINVAL));
1754 }
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_PUSHPAGE);
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 boolean_t
2979 dsl_dataset_is_before(dsl_dataset_t *later, dsl_dataset_t *earlier)
2980 {
2981 dsl_pool_t *dp = later->ds_dir->dd_pool;
2982 int error;
2983 boolean_t ret;
2984 dsl_dataset_t *origin;
2985
2986 ASSERT(dsl_pool_config_held(dp));
2987
2988 if (earlier->ds_phys->ds_creation_txg >=
2989 later->ds_phys->ds_creation_txg)
2990 return (B_FALSE);
2991
2992 if (later->ds_dir == earlier->ds_dir)
2993 return (B_TRUE);
2994 if (!dsl_dir_is_clone(later->ds_dir))
2995 return (B_FALSE);
2996
2997 if (later->ds_dir->dd_phys->dd_origin_obj == earlier->ds_object)
2998 return (B_TRUE);
2999 error = dsl_dataset_hold_obj(dp,
3000 later->ds_dir->dd_phys->dd_origin_obj, FTAG, &origin);
3001 if (error != 0)
3002 return (B_FALSE);
3003 ret = dsl_dataset_is_before(origin, earlier);
3004 dsl_dataset_rele(origin, FTAG);
3005 return (ret);
3006 }
3007
3008
3009 void
3010 dsl_dataset_zapify(dsl_dataset_t *ds, dmu_tx_t *tx)
3011 {
3012 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
3013 dmu_object_zapify(mos, ds->ds_object, DMU_OT_DSL_DATASET, tx);
3014 }
3015
3016 #if defined(_KERNEL) && defined(HAVE_SPL)
3017 EXPORT_SYMBOL(dsl_dataset_hold);
3018 EXPORT_SYMBOL(dsl_dataset_hold_obj);
3019 EXPORT_SYMBOL(dsl_dataset_own);
3020 EXPORT_SYMBOL(dsl_dataset_own_obj);
3021 EXPORT_SYMBOL(dsl_dataset_name);
3022 EXPORT_SYMBOL(dsl_dataset_rele);
3023 EXPORT_SYMBOL(dsl_dataset_disown);
3024 EXPORT_SYMBOL(dsl_dataset_tryown);
3025 EXPORT_SYMBOL(dsl_dataset_create_sync);
3026 EXPORT_SYMBOL(dsl_dataset_create_sync_dd);
3027 EXPORT_SYMBOL(dsl_dataset_snapshot_check);
3028 EXPORT_SYMBOL(dsl_dataset_snapshot_sync);
3029 EXPORT_SYMBOL(dsl_dataset_promote);
3030 EXPORT_SYMBOL(dsl_dataset_user_hold);
3031 EXPORT_SYMBOL(dsl_dataset_user_release);
3032 EXPORT_SYMBOL(dsl_dataset_get_holds);
3033 EXPORT_SYMBOL(dsl_dataset_get_blkptr);
3034 EXPORT_SYMBOL(dsl_dataset_set_blkptr);
3035 EXPORT_SYMBOL(dsl_dataset_get_spa);
3036 EXPORT_SYMBOL(dsl_dataset_modified_since_snap);
3037 EXPORT_SYMBOL(dsl_dataset_space_written);
3038 EXPORT_SYMBOL(dsl_dataset_space_wouldfree);
3039 EXPORT_SYMBOL(dsl_dataset_sync);
3040 EXPORT_SYMBOL(dsl_dataset_block_born);
3041 EXPORT_SYMBOL(dsl_dataset_block_kill);
3042 EXPORT_SYMBOL(dsl_dataset_block_freeable);
3043 EXPORT_SYMBOL(dsl_dataset_prev_snap_txg);
3044 EXPORT_SYMBOL(dsl_dataset_dirty);
3045 EXPORT_SYMBOL(dsl_dataset_stats);
3046 EXPORT_SYMBOL(dsl_dataset_fast_stat);
3047 EXPORT_SYMBOL(dsl_dataset_space);
3048 EXPORT_SYMBOL(dsl_dataset_fsid_guid);
3049 EXPORT_SYMBOL(dsl_dsobj_to_dsname);
3050 EXPORT_SYMBOL(dsl_dataset_check_quota);
3051 EXPORT_SYMBOL(dsl_dataset_clone_swap_check_impl);
3052 EXPORT_SYMBOL(dsl_dataset_clone_swap_sync_impl);
3053 #endif
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