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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 #include <sys/dsl_bookmark.h>
52
53 #define SWITCH64(x, y) \
54 { \
55 uint64_t __tmp = (x); \
56 (x) = (y); \
57 (y) = __tmp; \
58 }
59
60 #define DS_REF_MAX (1ULL << 62)
61
62 #define DSL_DEADLIST_BLOCKSIZE SPA_MAXBLOCKSIZE
63
64 /*
65 * Figure out how much of this delta should be propogated to the dsl_dir
66 * layer. If there's a refreservation, that space has already been
67 * partially accounted for in our ancestors.
68 */
69 static int64_t
70 parent_delta(dsl_dataset_t *ds, int64_t delta)
71 {
72 uint64_t old_bytes, new_bytes;
73
74 if (ds->ds_reserved == 0)
75 return (delta);
76
77 old_bytes = MAX(ds->ds_phys->ds_unique_bytes, ds->ds_reserved);
78 new_bytes = MAX(ds->ds_phys->ds_unique_bytes + delta, ds->ds_reserved);
79
80 ASSERT3U(ABS((int64_t)(new_bytes - old_bytes)), <=, ABS(delta));
81 return (new_bytes - old_bytes);
82 }
83
84 void
85 dsl_dataset_block_born(dsl_dataset_t *ds, const blkptr_t *bp, dmu_tx_t *tx)
86 {
87 int used, compressed, uncompressed;
88 int64_t delta;
89
90 used = bp_get_dsize_sync(tx->tx_pool->dp_spa, bp);
91 compressed = BP_GET_PSIZE(bp);
92 uncompressed = BP_GET_UCSIZE(bp);
93
94 dprintf_bp(bp, "ds=%p", ds);
95
96 ASSERT(dmu_tx_is_syncing(tx));
97 /* It could have been compressed away to nothing */
98 if (BP_IS_HOLE(bp))
99 return;
100 ASSERT(BP_GET_TYPE(bp) != DMU_OT_NONE);
101 ASSERT(DMU_OT_IS_VALID(BP_GET_TYPE(bp)));
102 if (ds == NULL) {
103 dsl_pool_mos_diduse_space(tx->tx_pool,
104 used, compressed, uncompressed);
105 return;
106 }
107
108 dmu_buf_will_dirty(ds->ds_dbuf, tx);
109 mutex_enter(&ds->ds_lock);
110 delta = parent_delta(ds, used);
111 ds->ds_phys->ds_referenced_bytes += used;
112 ds->ds_phys->ds_compressed_bytes += compressed;
113 ds->ds_phys->ds_uncompressed_bytes += uncompressed;
114 ds->ds_phys->ds_unique_bytes += used;
115 mutex_exit(&ds->ds_lock);
116 dsl_dir_diduse_space(ds->ds_dir, DD_USED_HEAD, delta,
117 compressed, uncompressed, tx);
118 dsl_dir_transfer_space(ds->ds_dir, used - delta,
119 DD_USED_REFRSRV, DD_USED_HEAD, tx);
120 }
121
122 int
123 dsl_dataset_block_kill(dsl_dataset_t *ds, const blkptr_t *bp, dmu_tx_t *tx,
124 boolean_t async)
125 {
126 int used = bp_get_dsize_sync(tx->tx_pool->dp_spa, bp);
127 int compressed = BP_GET_PSIZE(bp);
128 int uncompressed = BP_GET_UCSIZE(bp);
129
130 if (BP_IS_HOLE(bp))
131 return (0);
132
133 ASSERT(dmu_tx_is_syncing(tx));
134 ASSERT(bp->blk_birth <= tx->tx_txg);
135
136 if (ds == NULL) {
137 dsl_free(tx->tx_pool, tx->tx_txg, bp);
138 dsl_pool_mos_diduse_space(tx->tx_pool,
139 -used, -compressed, -uncompressed);
140 return (used);
141 }
142 ASSERT3P(tx->tx_pool, ==, ds->ds_dir->dd_pool);
143
144 ASSERT(!dsl_dataset_is_snapshot(ds));
145 dmu_buf_will_dirty(ds->ds_dbuf, tx);
146
147 if (bp->blk_birth > ds->ds_phys->ds_prev_snap_txg) {
148 int64_t delta;
149
150 dprintf_bp(bp, "freeing ds=%llu", ds->ds_object);
151 dsl_free(tx->tx_pool, tx->tx_txg, bp);
152
153 mutex_enter(&ds->ds_lock);
154 ASSERT(ds->ds_phys->ds_unique_bytes >= used ||
155 !DS_UNIQUE_IS_ACCURATE(ds));
156 delta = parent_delta(ds, -used);
157 ds->ds_phys->ds_unique_bytes -= used;
158 mutex_exit(&ds->ds_lock);
159 dsl_dir_diduse_space(ds->ds_dir, DD_USED_HEAD,
160 delta, -compressed, -uncompressed, tx);
161 dsl_dir_transfer_space(ds->ds_dir, -used - delta,
162 DD_USED_REFRSRV, DD_USED_HEAD, tx);
163 } else {
164 dprintf_bp(bp, "putting on dead list: %s", "");
165 if (async) {
166 /*
167 * We are here as part of zio's write done callback,
168 * which means we're a zio interrupt thread. We can't
169 * call dsl_deadlist_insert() now because it may block
170 * waiting for I/O. Instead, put bp on the deferred
171 * queue and let dsl_pool_sync() finish the job.
172 */
173 bplist_append(&ds->ds_pending_deadlist, bp);
174 } else {
175 dsl_deadlist_insert(&ds->ds_deadlist, bp, tx);
176 }
177 ASSERT3U(ds->ds_prev->ds_object, ==,
178 ds->ds_phys->ds_prev_snap_obj);
179 ASSERT(ds->ds_prev->ds_phys->ds_num_children > 0);
180 /* if (bp->blk_birth > prev prev snap txg) prev unique += bs */
181 if (ds->ds_prev->ds_phys->ds_next_snap_obj ==
182 ds->ds_object && bp->blk_birth >
183 ds->ds_prev->ds_phys->ds_prev_snap_txg) {
184 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx);
185 mutex_enter(&ds->ds_prev->ds_lock);
186 ds->ds_prev->ds_phys->ds_unique_bytes += used;
187 mutex_exit(&ds->ds_prev->ds_lock);
188 }
189 if (bp->blk_birth > ds->ds_dir->dd_origin_txg) {
190 dsl_dir_transfer_space(ds->ds_dir, used,
191 DD_USED_HEAD, DD_USED_SNAP, tx);
192 }
193 }
194 mutex_enter(&ds->ds_lock);
195 ASSERT3U(ds->ds_phys->ds_referenced_bytes, >=, used);
196 ds->ds_phys->ds_referenced_bytes -= used;
197 ASSERT3U(ds->ds_phys->ds_compressed_bytes, >=, compressed);
198 ds->ds_phys->ds_compressed_bytes -= compressed;
199 ASSERT3U(ds->ds_phys->ds_uncompressed_bytes, >=, uncompressed);
200 ds->ds_phys->ds_uncompressed_bytes -= uncompressed;
201 mutex_exit(&ds->ds_lock);
202
203 return (used);
204 }
205
206 uint64_t
207 dsl_dataset_prev_snap_txg(dsl_dataset_t *ds)
208 {
209 uint64_t trysnap = 0;
210
211 if (ds == NULL)
212 return (0);
213 /*
214 * The snapshot creation could fail, but that would cause an
215 * incorrect FALSE return, which would only result in an
216 * overestimation of the amount of space that an operation would
217 * consume, which is OK.
218 *
219 * There's also a small window where we could miss a pending
220 * snapshot, because we could set the sync task in the quiescing
221 * phase. So this should only be used as a guess.
222 */
223 if (ds->ds_trysnap_txg >
224 spa_last_synced_txg(ds->ds_dir->dd_pool->dp_spa))
225 trysnap = ds->ds_trysnap_txg;
226 return (MAX(ds->ds_phys->ds_prev_snap_txg, trysnap));
227 }
228
229 boolean_t
230 dsl_dataset_block_freeable(dsl_dataset_t *ds, const blkptr_t *bp,
231 uint64_t blk_birth)
232 {
233 if (blk_birth <= dsl_dataset_prev_snap_txg(ds) ||
234 (bp != NULL && BP_IS_HOLE(bp)))
235 return (B_FALSE);
236
237 ddt_prefetch(dsl_dataset_get_spa(ds), bp);
238
239 return (B_TRUE);
240 }
241
242 /* ARGSUSED */
243 static void
244 dsl_dataset_evict(dmu_buf_t *db, void *dsv)
245 {
246 dsl_dataset_t *ds = dsv;
247
248 ASSERT(ds->ds_owner == NULL);
249
250 unique_remove(ds->ds_fsid_guid);
251
252 if (ds->ds_objset != NULL)
253 dmu_objset_evict(ds->ds_objset);
254
255 if (ds->ds_prev) {
256 dsl_dataset_rele(ds->ds_prev, ds);
257 ds->ds_prev = NULL;
258 }
259
260 bplist_destroy(&ds->ds_pending_deadlist);
261 if (ds->ds_phys->ds_deadlist_obj != 0)
262 dsl_deadlist_close(&ds->ds_deadlist);
263 if (ds->ds_dir)
264 dsl_dir_rele(ds->ds_dir, ds);
265
266 ASSERT(!list_link_active(&ds->ds_synced_link));
267
268 mutex_destroy(&ds->ds_lock);
269 mutex_destroy(&ds->ds_opening_lock);
270 refcount_destroy(&ds->ds_longholds);
271
272 kmem_free(ds, sizeof (dsl_dataset_t));
273 }
274
275 int
276 dsl_dataset_get_snapname(dsl_dataset_t *ds)
277 {
278 dsl_dataset_phys_t *headphys;
279 int err;
280 dmu_buf_t *headdbuf;
281 dsl_pool_t *dp = ds->ds_dir->dd_pool;
282 objset_t *mos = dp->dp_meta_objset;
283
284 if (ds->ds_snapname[0])
285 return (0);
286 if (ds->ds_phys->ds_next_snap_obj == 0)
287 return (0);
288
289 err = dmu_bonus_hold(mos, ds->ds_dir->dd_phys->dd_head_dataset_obj,
290 FTAG, &headdbuf);
291 if (err != 0)
292 return (err);
293 headphys = headdbuf->db_data;
294 err = zap_value_search(dp->dp_meta_objset,
295 headphys->ds_snapnames_zapobj, ds->ds_object, 0, ds->ds_snapname);
296 dmu_buf_rele(headdbuf, FTAG);
297 return (err);
298 }
299
300 int
301 dsl_dataset_snap_lookup(dsl_dataset_t *ds, const char *name, uint64_t *value)
302 {
303 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
304 uint64_t snapobj = ds->ds_phys->ds_snapnames_zapobj;
305 matchtype_t mt;
306 int err;
307
308 if (ds->ds_phys->ds_flags & DS_FLAG_CI_DATASET)
309 mt = MT_FIRST;
310 else
311 mt = MT_EXACT;
312
313 err = zap_lookup_norm(mos, snapobj, name, 8, 1,
314 value, mt, NULL, 0, NULL);
315 if (err == ENOTSUP && mt == MT_FIRST)
316 err = zap_lookup(mos, snapobj, name, 8, 1, value);
317 return (err);
318 }
319
320 int
321 dsl_dataset_snap_remove(dsl_dataset_t *ds, const char *name, dmu_tx_t *tx)
322 {
323 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
324 uint64_t snapobj = ds->ds_phys->ds_snapnames_zapobj;
325 matchtype_t mt;
326 int err;
327
328 dsl_dir_snap_cmtime_update(ds->ds_dir);
329
330 if (ds->ds_phys->ds_flags & DS_FLAG_CI_DATASET)
331 mt = MT_FIRST;
332 else
333 mt = MT_EXACT;
334
335 err = zap_remove_norm(mos, snapobj, name, mt, tx);
336 if (err == ENOTSUP && mt == MT_FIRST)
337 err = zap_remove(mos, snapobj, name, tx);
338 return (err);
339 }
340
341 int
342 dsl_dataset_hold_obj(dsl_pool_t *dp, uint64_t dsobj, void *tag,
343 dsl_dataset_t **dsp)
344 {
345 objset_t *mos = dp->dp_meta_objset;
346 dmu_buf_t *dbuf;
347 dsl_dataset_t *ds;
348 int err;
349 dmu_object_info_t doi;
350
351 ASSERT(dsl_pool_config_held(dp));
352
353 err = dmu_bonus_hold(mos, dsobj, tag, &dbuf);
354 if (err != 0)
355 return (err);
356
357 /* Make sure dsobj has the correct object type. */
358 dmu_object_info_from_db(dbuf, &doi);
359 if (doi.doi_bonus_type != DMU_OT_DSL_DATASET) {
360 dmu_buf_rele(dbuf, tag);
361 return (SET_ERROR(EINVAL));
362 }
363
364 ds = dmu_buf_get_user(dbuf);
365 if (ds == NULL) {
366 dsl_dataset_t *winner = NULL;
367
368 ds = kmem_zalloc(sizeof (dsl_dataset_t), KM_SLEEP);
369 ds->ds_dbuf = dbuf;
370 ds->ds_object = dsobj;
371 ds->ds_phys = dbuf->db_data;
372 list_link_init(&ds->ds_synced_link);
373
374 mutex_init(&ds->ds_lock, NULL, MUTEX_DEFAULT, NULL);
375 mutex_init(&ds->ds_opening_lock, NULL, MUTEX_DEFAULT, NULL);
376 mutex_init(&ds->ds_sendstream_lock, NULL, MUTEX_DEFAULT, NULL);
377 refcount_create(&ds->ds_longholds);
378
379 bplist_create(&ds->ds_pending_deadlist);
380 dsl_deadlist_open(&ds->ds_deadlist,
381 mos, ds->ds_phys->ds_deadlist_obj);
382
383 list_create(&ds->ds_sendstreams, sizeof (dmu_sendarg_t),
384 offsetof(dmu_sendarg_t, dsa_link));
385
386 if (err == 0) {
387 err = dsl_dir_hold_obj(dp,
388 ds->ds_phys->ds_dir_obj, NULL, ds, &ds->ds_dir);
389 }
390 if (err != 0) {
391 mutex_destroy(&ds->ds_lock);
392 mutex_destroy(&ds->ds_opening_lock);
393 refcount_destroy(&ds->ds_longholds);
394 bplist_destroy(&ds->ds_pending_deadlist);
395 dsl_deadlist_close(&ds->ds_deadlist);
396 kmem_free(ds, sizeof (dsl_dataset_t));
397 dmu_buf_rele(dbuf, tag);
398 return (err);
399 }
400
401 if (!dsl_dataset_is_snapshot(ds)) {
402 ds->ds_snapname[0] = '\0';
403 if (ds->ds_phys->ds_prev_snap_obj != 0) {
404 err = dsl_dataset_hold_obj(dp,
405 ds->ds_phys->ds_prev_snap_obj,
406 ds, &ds->ds_prev);
407 }
408 if (doi.doi_type == DMU_OTN_ZAP_METADATA) {
409 int zaperr = zap_lookup(mos, ds->ds_object,
410 DS_FIELD_BOOKMARK_NAMES,
411 sizeof (ds->ds_bookmarks), 1,
412 &ds->ds_bookmarks);
413 if (zaperr != ENOENT)
414 VERIFY0(zaperr);
415 }
416 } else {
417 if (zfs_flags & ZFS_DEBUG_SNAPNAMES)
418 err = dsl_dataset_get_snapname(ds);
419 if (err == 0 && ds->ds_phys->ds_userrefs_obj != 0) {
420 err = zap_count(
421 ds->ds_dir->dd_pool->dp_meta_objset,
422 ds->ds_phys->ds_userrefs_obj,
423 &ds->ds_userrefs);
424 }
425 }
426
427 if (err == 0 && !dsl_dataset_is_snapshot(ds)) {
428 err = dsl_prop_get_int_ds(ds,
429 zfs_prop_to_name(ZFS_PROP_REFRESERVATION),
430 &ds->ds_reserved);
431 if (err == 0) {
432 err = dsl_prop_get_int_ds(ds,
433 zfs_prop_to_name(ZFS_PROP_REFQUOTA),
434 &ds->ds_quota);
435 }
436 } else {
437 ds->ds_reserved = ds->ds_quota = 0;
438 }
439
440 if (err != 0 || (winner = dmu_buf_set_user_ie(dbuf, ds,
441 &ds->ds_phys, dsl_dataset_evict)) != NULL) {
442 bplist_destroy(&ds->ds_pending_deadlist);
443 dsl_deadlist_close(&ds->ds_deadlist);
444 if (ds->ds_prev)
445 dsl_dataset_rele(ds->ds_prev, ds);
446 dsl_dir_rele(ds->ds_dir, ds);
447 mutex_destroy(&ds->ds_lock);
448 mutex_destroy(&ds->ds_opening_lock);
449 refcount_destroy(&ds->ds_longholds);
450 kmem_free(ds, sizeof (dsl_dataset_t));
451 if (err != 0) {
452 dmu_buf_rele(dbuf, tag);
453 return (err);
454 }
455 ds = winner;
456 } else {
457 ds->ds_fsid_guid =
458 unique_insert(ds->ds_phys->ds_fsid_guid);
459 }
460 }
461 ASSERT3P(ds->ds_dbuf, ==, dbuf);
462 ASSERT3P(ds->ds_phys, ==, dbuf->db_data);
463 ASSERT(ds->ds_phys->ds_prev_snap_obj != 0 ||
464 spa_version(dp->dp_spa) < SPA_VERSION_ORIGIN ||
465 dp->dp_origin_snap == NULL || ds == dp->dp_origin_snap);
466 *dsp = ds;
467 return (0);
468 }
469
470 int
471 dsl_dataset_hold(dsl_pool_t *dp, const char *name,
472 void *tag, dsl_dataset_t **dsp)
473 {
474 dsl_dir_t *dd;
475 const char *snapname;
476 uint64_t obj;
477 int err = 0;
478
479 err = dsl_dir_hold(dp, name, FTAG, &dd, &snapname);
480 if (err != 0)
481 return (err);
482
483 ASSERT(dsl_pool_config_held(dp));
484 obj = dd->dd_phys->dd_head_dataset_obj;
485 if (obj != 0)
486 err = dsl_dataset_hold_obj(dp, obj, tag, dsp);
487 else
488 err = SET_ERROR(ENOENT);
489
490 /* we may be looking for a snapshot */
491 if (err == 0 && snapname != NULL) {
492 dsl_dataset_t *ds;
493
494 if (*snapname++ != '@') {
495 dsl_dataset_rele(*dsp, tag);
496 dsl_dir_rele(dd, FTAG);
497 return (SET_ERROR(ENOENT));
498 }
499
500 dprintf("looking for snapshot '%s'\n", snapname);
501 err = dsl_dataset_snap_lookup(*dsp, snapname, &obj);
502 if (err == 0)
503 err = dsl_dataset_hold_obj(dp, obj, tag, &ds);
504 dsl_dataset_rele(*dsp, tag);
505
506 if (err == 0) {
507 mutex_enter(&ds->ds_lock);
508 if (ds->ds_snapname[0] == 0)
509 (void) strlcpy(ds->ds_snapname, snapname,
510 sizeof (ds->ds_snapname));
511 mutex_exit(&ds->ds_lock);
512 *dsp = ds;
513 }
514 }
515
516 dsl_dir_rele(dd, FTAG);
517 return (err);
518 }
519
520 int
521 dsl_dataset_own_obj(dsl_pool_t *dp, uint64_t dsobj,
522 void *tag, dsl_dataset_t **dsp)
523 {
524 int err = dsl_dataset_hold_obj(dp, dsobj, tag, dsp);
525 if (err != 0)
526 return (err);
527 if (!dsl_dataset_tryown(*dsp, tag)) {
528 dsl_dataset_rele(*dsp, tag);
529 *dsp = NULL;
530 return (SET_ERROR(EBUSY));
531 }
532 return (0);
533 }
534
535 int
536 dsl_dataset_own(dsl_pool_t *dp, const char *name,
537 void *tag, dsl_dataset_t **dsp)
538 {
539 int err = dsl_dataset_hold(dp, name, tag, dsp);
540 if (err != 0)
541 return (err);
542 if (!dsl_dataset_tryown(*dsp, tag)) {
543 dsl_dataset_rele(*dsp, tag);
544 return (SET_ERROR(EBUSY));
545 }
546 return (0);
547 }
548
549 /*
550 * See the comment above dsl_pool_hold() for details. In summary, a long
551 * hold is used to prevent destruction of a dataset while the pool hold
552 * is dropped, allowing other concurrent operations (e.g. spa_sync()).
553 *
554 * The dataset and pool must be held when this function is called. After it
555 * is called, the pool hold may be released while the dataset is still held
556 * and accessed.
557 */
558 void
559 dsl_dataset_long_hold(dsl_dataset_t *ds, void *tag)
560 {
561 ASSERT(dsl_pool_config_held(ds->ds_dir->dd_pool));
562 (void) refcount_add(&ds->ds_longholds, tag);
563 }
564
565 void
566 dsl_dataset_long_rele(dsl_dataset_t *ds, void *tag)
567 {
568 (void) refcount_remove(&ds->ds_longholds, tag);
569 }
570
571 /* Return B_TRUE if there are any long holds on this dataset. */
572 boolean_t
573 dsl_dataset_long_held(dsl_dataset_t *ds)
574 {
575 return (!refcount_is_zero(&ds->ds_longholds));
576 }
577
578 void
579 dsl_dataset_name(dsl_dataset_t *ds, char *name)
580 {
581 if (ds == NULL) {
582 (void) strcpy(name, "mos");
583 } else {
584 dsl_dir_name(ds->ds_dir, name);
585 VERIFY0(dsl_dataset_get_snapname(ds));
586 if (ds->ds_snapname[0]) {
587 (void) strcat(name, "@");
588 /*
589 * We use a "recursive" mutex so that we
590 * can call dprintf_ds() with ds_lock held.
591 */
592 if (!MUTEX_HELD(&ds->ds_lock)) {
593 mutex_enter(&ds->ds_lock);
594 (void) strcat(name, ds->ds_snapname);
595 mutex_exit(&ds->ds_lock);
596 } else {
597 (void) strcat(name, ds->ds_snapname);
598 }
599 }
600 }
601 }
602
603 void
604 dsl_dataset_rele(dsl_dataset_t *ds, void *tag)
605 {
606 dmu_buf_rele(ds->ds_dbuf, tag);
607 }
608
609 void
610 dsl_dataset_disown(dsl_dataset_t *ds, void *tag)
611 {
612 ASSERT(ds->ds_owner == tag && ds->ds_dbuf != NULL);
613
614 mutex_enter(&ds->ds_lock);
615 ds->ds_owner = NULL;
616 mutex_exit(&ds->ds_lock);
617 dsl_dataset_long_rele(ds, tag);
618 if (ds->ds_dbuf != NULL)
619 dsl_dataset_rele(ds, tag);
620 else
621 dsl_dataset_evict(NULL, ds);
622 }
623
624 boolean_t
625 dsl_dataset_tryown(dsl_dataset_t *ds, void *tag)
626 {
627 boolean_t gotit = FALSE;
628
629 mutex_enter(&ds->ds_lock);
630 if (ds->ds_owner == NULL && !DS_IS_INCONSISTENT(ds)) {
631 ds->ds_owner = tag;
632 dsl_dataset_long_hold(ds, tag);
633 gotit = TRUE;
634 }
635 mutex_exit(&ds->ds_lock);
636 return (gotit);
637 }
638
639 uint64_t
640 dsl_dataset_create_sync_dd(dsl_dir_t *dd, dsl_dataset_t *origin,
641 uint64_t flags, dmu_tx_t *tx)
642 {
643 dsl_pool_t *dp = dd->dd_pool;
644 dmu_buf_t *dbuf;
645 dsl_dataset_phys_t *dsphys;
646 uint64_t dsobj;
647 objset_t *mos = dp->dp_meta_objset;
648
649 if (origin == NULL)
650 origin = dp->dp_origin_snap;
651
652 ASSERT(origin == NULL || origin->ds_dir->dd_pool == dp);
653 ASSERT(origin == NULL || origin->ds_phys->ds_num_children > 0);
654 ASSERT(dmu_tx_is_syncing(tx));
655 ASSERT(dd->dd_phys->dd_head_dataset_obj == 0);
656
657 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0,
658 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx);
659 VERIFY0(dmu_bonus_hold(mos, dsobj, FTAG, &dbuf));
660 dmu_buf_will_dirty(dbuf, tx);
661 dsphys = dbuf->db_data;
662 bzero(dsphys, sizeof (dsl_dataset_phys_t));
663 dsphys->ds_dir_obj = dd->dd_object;
664 dsphys->ds_flags = flags;
665 dsphys->ds_fsid_guid = unique_create();
666 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid,
667 sizeof (dsphys->ds_guid));
668 dsphys->ds_snapnames_zapobj =
669 zap_create_norm(mos, U8_TEXTPREP_TOUPPER, DMU_OT_DSL_DS_SNAP_MAP,
670 DMU_OT_NONE, 0, tx);
671 dsphys->ds_creation_time = gethrestime_sec();
672 dsphys->ds_creation_txg = tx->tx_txg == TXG_INITIAL ? 1 : tx->tx_txg;
673
674 if (origin == NULL) {
675 dsphys->ds_deadlist_obj = dsl_deadlist_alloc(mos, tx);
676 } else {
677 dsl_dataset_t *ohds; /* head of the origin snapshot */
678
679 dsphys->ds_prev_snap_obj = origin->ds_object;
680 dsphys->ds_prev_snap_txg =
681 origin->ds_phys->ds_creation_txg;
682 dsphys->ds_referenced_bytes =
683 origin->ds_phys->ds_referenced_bytes;
684 dsphys->ds_compressed_bytes =
685 origin->ds_phys->ds_compressed_bytes;
686 dsphys->ds_uncompressed_bytes =
687 origin->ds_phys->ds_uncompressed_bytes;
688 dsphys->ds_bp = origin->ds_phys->ds_bp;
689
690 /*
691 * Inherit flags that describe the dataset's contents
692 * (INCONSISTENT) or properties (Case Insensitive).
693 */
694 dsphys->ds_flags |= origin->ds_phys->ds_flags &
695 (DS_FLAG_INCONSISTENT | DS_FLAG_CI_DATASET);
696
697 dmu_buf_will_dirty(origin->ds_dbuf, tx);
698 origin->ds_phys->ds_num_children++;
699
700 VERIFY0(dsl_dataset_hold_obj(dp,
701 origin->ds_dir->dd_phys->dd_head_dataset_obj, FTAG, &ohds));
702 dsphys->ds_deadlist_obj = dsl_deadlist_clone(&ohds->ds_deadlist,
703 dsphys->ds_prev_snap_txg, dsphys->ds_prev_snap_obj, tx);
704 dsl_dataset_rele(ohds, FTAG);
705
706 if (spa_version(dp->dp_spa) >= SPA_VERSION_NEXT_CLONES) {
707 if (origin->ds_phys->ds_next_clones_obj == 0) {
708 origin->ds_phys->ds_next_clones_obj =
709 zap_create(mos,
710 DMU_OT_NEXT_CLONES, DMU_OT_NONE, 0, tx);
711 }
712 VERIFY0(zap_add_int(mos,
713 origin->ds_phys->ds_next_clones_obj, dsobj, tx));
714 }
715
716 dmu_buf_will_dirty(dd->dd_dbuf, tx);
717 dd->dd_phys->dd_origin_obj = origin->ds_object;
718 if (spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) {
719 if (origin->ds_dir->dd_phys->dd_clones == 0) {
720 dmu_buf_will_dirty(origin->ds_dir->dd_dbuf, tx);
721 origin->ds_dir->dd_phys->dd_clones =
722 zap_create(mos,
723 DMU_OT_DSL_CLONES, DMU_OT_NONE, 0, tx);
724 }
725 VERIFY0(zap_add_int(mos,
726 origin->ds_dir->dd_phys->dd_clones, dsobj, tx));
727 }
728 }
729
730 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE)
731 dsphys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE;
732
733 dmu_buf_rele(dbuf, FTAG);
734
735 dmu_buf_will_dirty(dd->dd_dbuf, tx);
736 dd->dd_phys->dd_head_dataset_obj = dsobj;
737
738 return (dsobj);
739 }
740
741 static void
742 dsl_dataset_zero_zil(dsl_dataset_t *ds, dmu_tx_t *tx)
743 {
744 objset_t *os;
745
746 VERIFY0(dmu_objset_from_ds(ds, &os));
747 bzero(&os->os_zil_header, sizeof (os->os_zil_header));
748 dsl_dataset_dirty(ds, tx);
749 }
750
751 uint64_t
752 dsl_dataset_create_sync(dsl_dir_t *pdd, const char *lastname,
753 dsl_dataset_t *origin, uint64_t flags, cred_t *cr, dmu_tx_t *tx)
754 {
755 dsl_pool_t *dp = pdd->dd_pool;
756 uint64_t dsobj, ddobj;
757 dsl_dir_t *dd;
758
759 ASSERT(dmu_tx_is_syncing(tx));
760 ASSERT(lastname[0] != '@');
761
762 ddobj = dsl_dir_create_sync(dp, pdd, lastname, tx);
763 VERIFY0(dsl_dir_hold_obj(dp, ddobj, lastname, FTAG, &dd));
764
765 dsobj = dsl_dataset_create_sync_dd(dd, origin,
766 flags & ~DS_CREATE_FLAG_NODIRTY, tx);
767
768 dsl_deleg_set_create_perms(dd, tx, cr);
769
770 dsl_dir_rele(dd, FTAG);
771
772 /*
773 * If we are creating a clone, make sure we zero out any stale
774 * data from the origin snapshots zil header.
775 */
776 if (origin != NULL && !(flags & DS_CREATE_FLAG_NODIRTY)) {
777 dsl_dataset_t *ds;
778
779 VERIFY0(dsl_dataset_hold_obj(dp, dsobj, FTAG, &ds));
780 dsl_dataset_zero_zil(ds, tx);
781 dsl_dataset_rele(ds, FTAG);
782 }
783
784 return (dsobj);
785 }
786
787 /*
788 * The unique space in the head dataset can be calculated by subtracting
789 * the space used in the most recent snapshot, that is still being used
790 * in this file system, from the space currently in use. To figure out
791 * the space in the most recent snapshot still in use, we need to take
792 * the total space used in the snapshot and subtract out the space that
793 * has been freed up since the snapshot was taken.
794 */
795 void
796 dsl_dataset_recalc_head_uniq(dsl_dataset_t *ds)
797 {
798 uint64_t mrs_used;
799 uint64_t dlused, dlcomp, dluncomp;
800
801 ASSERT(!dsl_dataset_is_snapshot(ds));
802
803 if (ds->ds_phys->ds_prev_snap_obj != 0)
804 mrs_used = ds->ds_prev->ds_phys->ds_referenced_bytes;
805 else
806 mrs_used = 0;
807
808 dsl_deadlist_space(&ds->ds_deadlist, &dlused, &dlcomp, &dluncomp);
809
810 ASSERT3U(dlused, <=, mrs_used);
811 ds->ds_phys->ds_unique_bytes =
812 ds->ds_phys->ds_referenced_bytes - (mrs_used - dlused);
813
814 if (spa_version(ds->ds_dir->dd_pool->dp_spa) >=
815 SPA_VERSION_UNIQUE_ACCURATE)
816 ds->ds_phys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE;
817 }
818
819 void
820 dsl_dataset_remove_from_next_clones(dsl_dataset_t *ds, uint64_t obj,
821 dmu_tx_t *tx)
822 {
823 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
824 int err;
825 ASSERTV(uint64_t count);
826
827 ASSERT(ds->ds_phys->ds_num_children >= 2);
828 err = zap_remove_int(mos, ds->ds_phys->ds_next_clones_obj, obj, tx);
829 /*
830 * The err should not be ENOENT, but a bug in a previous version
831 * of the code could cause upgrade_clones_cb() to not set
832 * ds_next_snap_obj when it should, leading to a missing entry.
833 * If we knew that the pool was created after
834 * SPA_VERSION_NEXT_CLONES, we could assert that it isn't
835 * ENOENT. However, at least we can check that we don't have
836 * too many entries in the next_clones_obj even after failing to
837 * remove this one.
838 */
839 if (err != ENOENT)
840 VERIFY0(err);
841 ASSERT0(zap_count(mos, ds->ds_phys->ds_next_clones_obj,
842 &count));
843 ASSERT3U(count, <=, ds->ds_phys->ds_num_children - 2);
844 }
845
846
847 blkptr_t *
848 dsl_dataset_get_blkptr(dsl_dataset_t *ds)
849 {
850 return (&ds->ds_phys->ds_bp);
851 }
852
853 void
854 dsl_dataset_set_blkptr(dsl_dataset_t *ds, blkptr_t *bp, dmu_tx_t *tx)
855 {
856 ASSERT(dmu_tx_is_syncing(tx));
857 /* If it's the meta-objset, set dp_meta_rootbp */
858 if (ds == NULL) {
859 tx->tx_pool->dp_meta_rootbp = *bp;
860 } else {
861 dmu_buf_will_dirty(ds->ds_dbuf, tx);
862 ds->ds_phys->ds_bp = *bp;
863 }
864 }
865
866 spa_t *
867 dsl_dataset_get_spa(dsl_dataset_t *ds)
868 {
869 return (ds->ds_dir->dd_pool->dp_spa);
870 }
871
872 void
873 dsl_dataset_dirty(dsl_dataset_t *ds, dmu_tx_t *tx)
874 {
875 dsl_pool_t *dp;
876
877 if (ds == NULL) /* this is the meta-objset */
878 return;
879
880 ASSERT(ds->ds_objset != NULL);
881
882 if (ds->ds_phys->ds_next_snap_obj != 0)
883 panic("dirtying snapshot!");
884
885 dp = ds->ds_dir->dd_pool;
886
887 if (txg_list_add(&dp->dp_dirty_datasets, ds, tx->tx_txg)) {
888 /* up the hold count until we can be written out */
889 dmu_buf_add_ref(ds->ds_dbuf, ds);
890 }
891 }
892
893 boolean_t
894 dsl_dataset_is_dirty(dsl_dataset_t *ds)
895 {
896 int t;
897
898 for (t = 0; t < TXG_SIZE; t++) {
899 if (txg_list_member(&ds->ds_dir->dd_pool->dp_dirty_datasets,
900 ds, t))
901 return (B_TRUE);
902 }
903 return (B_FALSE);
904 }
905
906 static int
907 dsl_dataset_snapshot_reserve_space(dsl_dataset_t *ds, dmu_tx_t *tx)
908 {
909 uint64_t asize;
910
911 if (!dmu_tx_is_syncing(tx))
912 return (0);
913
914 /*
915 * If there's an fs-only reservation, any blocks that might become
916 * owned by the snapshot dataset must be accommodated by space
917 * outside of the reservation.
918 */
919 ASSERT(ds->ds_reserved == 0 || DS_UNIQUE_IS_ACCURATE(ds));
920 asize = MIN(ds->ds_phys->ds_unique_bytes, ds->ds_reserved);
921 if (asize > dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE))
922 return (SET_ERROR(ENOSPC));
923
924 /*
925 * Propagate any reserved space for this snapshot to other
926 * snapshot checks in this sync group.
927 */
928 if (asize > 0)
929 dsl_dir_willuse_space(ds->ds_dir, asize, tx);
930
931 return (0);
932 }
933
934 typedef struct dsl_dataset_snapshot_arg {
935 nvlist_t *ddsa_snaps;
936 nvlist_t *ddsa_props;
937 nvlist_t *ddsa_errors;
938 } dsl_dataset_snapshot_arg_t;
939
940 int
941 dsl_dataset_snapshot_check_impl(dsl_dataset_t *ds, const char *snapname,
942 dmu_tx_t *tx, boolean_t recv)
943 {
944 int error;
945 uint64_t value;
946
947 ds->ds_trysnap_txg = tx->tx_txg;
948
949 if (!dmu_tx_is_syncing(tx))
950 return (0);
951
952 /*
953 * We don't allow multiple snapshots of the same txg. If there
954 * is already one, try again.
955 */
956 if (ds->ds_phys->ds_prev_snap_txg >= tx->tx_txg)
957 return (SET_ERROR(EAGAIN));
958
959 /*
960 * Check for conflicting snapshot name.
961 */
962 error = dsl_dataset_snap_lookup(ds, snapname, &value);
963 if (error == 0)
964 return (SET_ERROR(EEXIST));
965 if (error != ENOENT)
966 return (error);
967
968 /*
969 * We don't allow taking snapshots of inconsistent datasets, such as
970 * those into which we are currently receiving. However, if we are
971 * creating this snapshot as part of a receive, this check will be
972 * executed atomically with respect to the completion of the receive
973 * itself but prior to the clearing of DS_FLAG_INCONSISTENT; in this
974 * case we ignore this, knowing it will be fixed up for us shortly in
975 * dmu_recv_end_sync().
976 */
977 if (!recv && DS_IS_INCONSISTENT(ds))
978 return (SET_ERROR(EBUSY));
979
980 error = dsl_dataset_snapshot_reserve_space(ds, tx);
981 if (error != 0)
982 return (error);
983
984 return (0);
985 }
986
987 static int
988 dsl_dataset_snapshot_check(void *arg, dmu_tx_t *tx)
989 {
990 dsl_dataset_snapshot_arg_t *ddsa = arg;
991 dsl_pool_t *dp = dmu_tx_pool(tx);
992 nvpair_t *pair;
993 int rv = 0;
994
995 for (pair = nvlist_next_nvpair(ddsa->ddsa_snaps, NULL);
996 pair != NULL; pair = nvlist_next_nvpair(ddsa->ddsa_snaps, pair)) {
997 int error = 0;
998 dsl_dataset_t *ds;
999 char *name, *atp;
1000 char dsname[MAXNAMELEN];
1001
1002 name = nvpair_name(pair);
1003 if (strlen(name) >= MAXNAMELEN)
1004 error = SET_ERROR(ENAMETOOLONG);
1005 if (error == 0) {
1006 atp = strchr(name, '@');
1007 if (atp == NULL)
1008 error = SET_ERROR(EINVAL);
1009 if (error == 0)
1010 (void) strlcpy(dsname, name, atp - name + 1);
1011 }
1012 if (error == 0)
1013 error = dsl_dataset_hold(dp, dsname, FTAG, &ds);
1014 if (error == 0) {
1015 error = dsl_dataset_snapshot_check_impl(ds,
1016 atp + 1, tx, B_FALSE);
1017 dsl_dataset_rele(ds, FTAG);
1018 }
1019
1020 if (error != 0) {
1021 if (ddsa->ddsa_errors != NULL) {
1022 fnvlist_add_int32(ddsa->ddsa_errors,
1023 name, error);
1024 }
1025 rv = error;
1026 }
1027 }
1028 return (rv);
1029 }
1030
1031 void
1032 dsl_dataset_snapshot_sync_impl(dsl_dataset_t *ds, const char *snapname,
1033 dmu_tx_t *tx)
1034 {
1035 dsl_pool_t *dp = ds->ds_dir->dd_pool;
1036 dmu_buf_t *dbuf;
1037 dsl_dataset_phys_t *dsphys;
1038 uint64_t dsobj, crtxg;
1039 objset_t *mos = dp->dp_meta_objset;
1040 ASSERTV(static zil_header_t zero_zil);
1041 ASSERTV(objset_t *os);
1042
1043 ASSERT(RRW_WRITE_HELD(&dp->dp_config_rwlock));
1044
1045 /*
1046 * If we are on an old pool, the zil must not be active, in which
1047 * case it will be zeroed. Usually zil_suspend() accomplishes this.
1048 */
1049 ASSERT(spa_version(dmu_tx_pool(tx)->dp_spa) >= SPA_VERSION_FAST_SNAP ||
1050 dmu_objset_from_ds(ds, &os) != 0 ||
1051 bcmp(&os->os_phys->os_zil_header, &zero_zil,
1052 sizeof (zero_zil)) == 0);
1053
1054
1055 /*
1056 * The origin's ds_creation_txg has to be < TXG_INITIAL
1057 */
1058 if (strcmp(snapname, ORIGIN_DIR_NAME) == 0)
1059 crtxg = 1;
1060 else
1061 crtxg = tx->tx_txg;
1062
1063 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0,
1064 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx);
1065 VERIFY0(dmu_bonus_hold(mos, dsobj, FTAG, &dbuf));
1066 dmu_buf_will_dirty(dbuf, tx);
1067 dsphys = dbuf->db_data;
1068 bzero(dsphys, sizeof (dsl_dataset_phys_t));
1069 dsphys->ds_dir_obj = ds->ds_dir->dd_object;
1070 dsphys->ds_fsid_guid = unique_create();
1071 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid,
1072 sizeof (dsphys->ds_guid));
1073 dsphys->ds_prev_snap_obj = ds->ds_phys->ds_prev_snap_obj;
1074 dsphys->ds_prev_snap_txg = ds->ds_phys->ds_prev_snap_txg;
1075 dsphys->ds_next_snap_obj = ds->ds_object;
1076 dsphys->ds_num_children = 1;
1077 dsphys->ds_creation_time = gethrestime_sec();
1078 dsphys->ds_creation_txg = crtxg;
1079 dsphys->ds_deadlist_obj = ds->ds_phys->ds_deadlist_obj;
1080 dsphys->ds_referenced_bytes = ds->ds_phys->ds_referenced_bytes;
1081 dsphys->ds_compressed_bytes = ds->ds_phys->ds_compressed_bytes;
1082 dsphys->ds_uncompressed_bytes = ds->ds_phys->ds_uncompressed_bytes;
1083 dsphys->ds_flags = ds->ds_phys->ds_flags;
1084 dsphys->ds_bp = ds->ds_phys->ds_bp;
1085 dmu_buf_rele(dbuf, FTAG);
1086
1087 ASSERT3U(ds->ds_prev != 0, ==, ds->ds_phys->ds_prev_snap_obj != 0);
1088 if (ds->ds_prev) {
1089 uint64_t next_clones_obj =
1090 ds->ds_prev->ds_phys->ds_next_clones_obj;
1091 ASSERT(ds->ds_prev->ds_phys->ds_next_snap_obj ==
1092 ds->ds_object ||
1093 ds->ds_prev->ds_phys->ds_num_children > 1);
1094 if (ds->ds_prev->ds_phys->ds_next_snap_obj == ds->ds_object) {
1095 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx);
1096 ASSERT3U(ds->ds_phys->ds_prev_snap_txg, ==,
1097 ds->ds_prev->ds_phys->ds_creation_txg);
1098 ds->ds_prev->ds_phys->ds_next_snap_obj = dsobj;
1099 } else if (next_clones_obj != 0) {
1100 dsl_dataset_remove_from_next_clones(ds->ds_prev,
1101 dsphys->ds_next_snap_obj, tx);
1102 VERIFY0(zap_add_int(mos,
1103 next_clones_obj, dsobj, tx));
1104 }
1105 }
1106
1107 /*
1108 * If we have a reference-reservation on this dataset, we will
1109 * need to increase the amount of refreservation being charged
1110 * since our unique space is going to zero.
1111 */
1112 if (ds->ds_reserved) {
1113 int64_t delta;
1114 ASSERT(DS_UNIQUE_IS_ACCURATE(ds));
1115 delta = MIN(ds->ds_phys->ds_unique_bytes, ds->ds_reserved);
1116 dsl_dir_diduse_space(ds->ds_dir, DD_USED_REFRSRV,
1117 delta, 0, 0, tx);
1118 }
1119
1120 dmu_buf_will_dirty(ds->ds_dbuf, tx);
1121 ds->ds_phys->ds_deadlist_obj = dsl_deadlist_clone(&ds->ds_deadlist,
1122 UINT64_MAX, ds->ds_phys->ds_prev_snap_obj, tx);
1123 dsl_deadlist_close(&ds->ds_deadlist);
1124 dsl_deadlist_open(&ds->ds_deadlist, mos, ds->ds_phys->ds_deadlist_obj);
1125 dsl_deadlist_add_key(&ds->ds_deadlist,
1126 ds->ds_phys->ds_prev_snap_txg, tx);
1127
1128 ASSERT3U(ds->ds_phys->ds_prev_snap_txg, <, tx->tx_txg);
1129 ds->ds_phys->ds_prev_snap_obj = dsobj;
1130 ds->ds_phys->ds_prev_snap_txg = crtxg;
1131 ds->ds_phys->ds_unique_bytes = 0;
1132 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE)
1133 ds->ds_phys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE;
1134
1135 VERIFY0(zap_add(mos, ds->ds_phys->ds_snapnames_zapobj,
1136 snapname, 8, 1, &dsobj, tx));
1137
1138 if (ds->ds_prev)
1139 dsl_dataset_rele(ds->ds_prev, ds);
1140 VERIFY0(dsl_dataset_hold_obj(dp,
1141 ds->ds_phys->ds_prev_snap_obj, ds, &ds->ds_prev));
1142
1143 dsl_scan_ds_snapshotted(ds, tx);
1144
1145 dsl_dir_snap_cmtime_update(ds->ds_dir);
1146
1147 spa_history_log_internal_ds(ds->ds_prev, "snapshot", tx, "");
1148 }
1149
1150 static void
1151 dsl_dataset_snapshot_sync(void *arg, dmu_tx_t *tx)
1152 {
1153 dsl_dataset_snapshot_arg_t *ddsa = arg;
1154 dsl_pool_t *dp = dmu_tx_pool(tx);
1155 nvpair_t *pair;
1156
1157 for (pair = nvlist_next_nvpair(ddsa->ddsa_snaps, NULL);
1158 pair != NULL; pair = nvlist_next_nvpair(ddsa->ddsa_snaps, pair)) {
1159 dsl_dataset_t *ds;
1160 char *name, *atp;
1161 char dsname[MAXNAMELEN];
1162
1163 name = nvpair_name(pair);
1164 atp = strchr(name, '@');
1165 (void) strlcpy(dsname, name, atp - name + 1);
1166 VERIFY0(dsl_dataset_hold(dp, dsname, FTAG, &ds));
1167
1168 dsl_dataset_snapshot_sync_impl(ds, atp + 1, tx);
1169 if (ddsa->ddsa_props != NULL) {
1170 dsl_props_set_sync_impl(ds->ds_prev,
1171 ZPROP_SRC_LOCAL, ddsa->ddsa_props, tx);
1172 }
1173 dsl_dataset_rele(ds, FTAG);
1174 }
1175 }
1176
1177 /*
1178 * The snapshots must all be in the same pool.
1179 * All-or-nothing: if there are any failures, nothing will be modified.
1180 */
1181 int
1182 dsl_dataset_snapshot(nvlist_t *snaps, nvlist_t *props, nvlist_t *errors)
1183 {
1184 dsl_dataset_snapshot_arg_t ddsa;
1185 nvpair_t *pair;
1186 boolean_t needsuspend;
1187 int error;
1188 spa_t *spa;
1189 char *firstname;
1190 nvlist_t *suspended = NULL;
1191
1192 pair = nvlist_next_nvpair(snaps, NULL);
1193 if (pair == NULL)
1194 return (0);
1195 firstname = nvpair_name(pair);
1196
1197 error = spa_open(firstname, &spa, FTAG);
1198 if (error != 0)
1199 return (error);
1200 needsuspend = (spa_version(spa) < SPA_VERSION_FAST_SNAP);
1201 spa_close(spa, FTAG);
1202
1203 if (needsuspend) {
1204 suspended = fnvlist_alloc();
1205 for (pair = nvlist_next_nvpair(snaps, NULL); pair != NULL;
1206 pair = nvlist_next_nvpair(snaps, pair)) {
1207 char fsname[MAXNAMELEN];
1208 char *snapname = nvpair_name(pair);
1209 char *atp;
1210 void *cookie;
1211
1212 atp = strchr(snapname, '@');
1213 if (atp == NULL) {
1214 error = SET_ERROR(EINVAL);
1215 break;
1216 }
1217 (void) strlcpy(fsname, snapname, atp - snapname + 1);
1218
1219 error = zil_suspend(fsname, &cookie);
1220 if (error != 0)
1221 break;
1222 fnvlist_add_uint64(suspended, fsname,
1223 (uintptr_t)cookie);
1224 }
1225 }
1226
1227 ddsa.ddsa_snaps = snaps;
1228 ddsa.ddsa_props = props;
1229 ddsa.ddsa_errors = errors;
1230
1231 if (error == 0) {
1232 error = dsl_sync_task(firstname, dsl_dataset_snapshot_check,
1233 dsl_dataset_snapshot_sync, &ddsa,
1234 fnvlist_num_pairs(snaps) * 3);
1235 }
1236
1237 if (suspended != NULL) {
1238 for (pair = nvlist_next_nvpair(suspended, NULL); pair != NULL;
1239 pair = nvlist_next_nvpair(suspended, pair)) {
1240 zil_resume((void *)(uintptr_t)
1241 fnvpair_value_uint64(pair));
1242 }
1243 fnvlist_free(suspended);
1244 }
1245
1246 #ifdef _KERNEL
1247 if (error == 0) {
1248 for (pair = nvlist_next_nvpair(snaps, NULL); pair != NULL;
1249 pair = nvlist_next_nvpair(snaps, pair)) {
1250 char *snapname = nvpair_name(pair);
1251 zvol_create_minors(snapname);
1252 }
1253 }
1254 #endif
1255
1256 return (error);
1257 }
1258
1259 typedef struct dsl_dataset_snapshot_tmp_arg {
1260 const char *ddsta_fsname;
1261 const char *ddsta_snapname;
1262 minor_t ddsta_cleanup_minor;
1263 const char *ddsta_htag;
1264 } dsl_dataset_snapshot_tmp_arg_t;
1265
1266 static int
1267 dsl_dataset_snapshot_tmp_check(void *arg, dmu_tx_t *tx)
1268 {
1269 dsl_dataset_snapshot_tmp_arg_t *ddsta = arg;
1270 dsl_pool_t *dp = dmu_tx_pool(tx);
1271 dsl_dataset_t *ds;
1272 int error;
1273
1274 error = dsl_dataset_hold(dp, ddsta->ddsta_fsname, FTAG, &ds);
1275 if (error != 0)
1276 return (error);
1277
1278 error = dsl_dataset_snapshot_check_impl(ds, ddsta->ddsta_snapname,
1279 tx, B_FALSE);
1280 if (error != 0) {
1281 dsl_dataset_rele(ds, FTAG);
1282 return (error);
1283 }
1284
1285 if (spa_version(dp->dp_spa) < SPA_VERSION_USERREFS) {
1286 dsl_dataset_rele(ds, FTAG);
1287 return (SET_ERROR(ENOTSUP));
1288 }
1289 error = dsl_dataset_user_hold_check_one(NULL, ddsta->ddsta_htag,
1290 B_TRUE, tx);
1291 if (error != 0) {
1292 dsl_dataset_rele(ds, FTAG);
1293 return (error);
1294 }
1295
1296 dsl_dataset_rele(ds, FTAG);
1297 return (0);
1298 }
1299
1300 static void
1301 dsl_dataset_snapshot_tmp_sync(void *arg, dmu_tx_t *tx)
1302 {
1303 dsl_dataset_snapshot_tmp_arg_t *ddsta = arg;
1304 dsl_pool_t *dp = dmu_tx_pool(tx);
1305 dsl_dataset_t *ds;
1306
1307 VERIFY0(dsl_dataset_hold(dp, ddsta->ddsta_fsname, FTAG, &ds));
1308
1309 dsl_dataset_snapshot_sync_impl(ds, ddsta->ddsta_snapname, tx);
1310 dsl_dataset_user_hold_sync_one(ds->ds_prev, ddsta->ddsta_htag,
1311 ddsta->ddsta_cleanup_minor, gethrestime_sec(), tx);
1312 dsl_destroy_snapshot_sync_impl(ds->ds_prev, B_TRUE, tx);
1313
1314 dsl_dataset_rele(ds, FTAG);
1315 }
1316
1317 int
1318 dsl_dataset_snapshot_tmp(const char *fsname, const char *snapname,
1319 minor_t cleanup_minor, const char *htag)
1320 {
1321 dsl_dataset_snapshot_tmp_arg_t ddsta;
1322 int error;
1323 spa_t *spa;
1324 boolean_t needsuspend;
1325 void *cookie;
1326
1327 ddsta.ddsta_fsname = fsname;
1328 ddsta.ddsta_snapname = snapname;
1329 ddsta.ddsta_cleanup_minor = cleanup_minor;
1330 ddsta.ddsta_htag = htag;
1331
1332 error = spa_open(fsname, &spa, FTAG);
1333 if (error != 0)
1334 return (error);
1335 needsuspend = (spa_version(spa) < SPA_VERSION_FAST_SNAP);
1336 spa_close(spa, FTAG);
1337
1338 if (needsuspend) {
1339 error = zil_suspend(fsname, &cookie);
1340 if (error != 0)
1341 return (error);
1342 }
1343
1344 error = dsl_sync_task(fsname, dsl_dataset_snapshot_tmp_check,
1345 dsl_dataset_snapshot_tmp_sync, &ddsta, 3);
1346
1347 if (needsuspend)
1348 zil_resume(cookie);
1349 return (error);
1350 }
1351
1352
1353 void
1354 dsl_dataset_sync(dsl_dataset_t *ds, zio_t *zio, dmu_tx_t *tx)
1355 {
1356 ASSERT(dmu_tx_is_syncing(tx));
1357 ASSERT(ds->ds_objset != NULL);
1358 ASSERT(ds->ds_phys->ds_next_snap_obj == 0);
1359
1360 /*
1361 * in case we had to change ds_fsid_guid when we opened it,
1362 * sync it out now.
1363 */
1364 dmu_buf_will_dirty(ds->ds_dbuf, tx);
1365 ds->ds_phys->ds_fsid_guid = ds->ds_fsid_guid;
1366
1367 dmu_objset_sync(ds->ds_objset, zio, tx);
1368 }
1369
1370 static void
1371 get_clones_stat(dsl_dataset_t *ds, nvlist_t *nv)
1372 {
1373 uint64_t count = 0;
1374 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
1375 zap_cursor_t zc;
1376 zap_attribute_t za;
1377 nvlist_t *propval = fnvlist_alloc();
1378 nvlist_t *val = fnvlist_alloc();
1379
1380 ASSERT(dsl_pool_config_held(ds->ds_dir->dd_pool));
1381
1382 /*
1383 * There may be missing entries in ds_next_clones_obj
1384 * due to a bug in a previous version of the code.
1385 * Only trust it if it has the right number of entries.
1386 */
1387 if (ds->ds_phys->ds_next_clones_obj != 0) {
1388 VERIFY0(zap_count(mos, ds->ds_phys->ds_next_clones_obj,
1389 &count));
1390 }
1391 if (count != ds->ds_phys->ds_num_children - 1)
1392 goto fail;
1393 for (zap_cursor_init(&zc, mos, ds->ds_phys->ds_next_clones_obj);
1394 zap_cursor_retrieve(&zc, &za) == 0;
1395 zap_cursor_advance(&zc)) {
1396 dsl_dataset_t *clone;
1397 char buf[ZFS_MAXNAMELEN];
1398 VERIFY0(dsl_dataset_hold_obj(ds->ds_dir->dd_pool,
1399 za.za_first_integer, FTAG, &clone));
1400 dsl_dir_name(clone->ds_dir, buf);
1401 fnvlist_add_boolean(val, buf);
1402 dsl_dataset_rele(clone, FTAG);
1403 }
1404 zap_cursor_fini(&zc);
1405 fnvlist_add_nvlist(propval, ZPROP_VALUE, val);
1406 fnvlist_add_nvlist(nv, zfs_prop_to_name(ZFS_PROP_CLONES), propval);
1407 fail:
1408 nvlist_free(val);
1409 nvlist_free(propval);
1410 }
1411
1412 void
1413 dsl_dataset_stats(dsl_dataset_t *ds, nvlist_t *nv)
1414 {
1415 uint64_t refd, avail, uobjs, aobjs, ratio;
1416 ASSERTV(dsl_pool_t *dp = ds->ds_dir->dd_pool);
1417
1418 ASSERT(dsl_pool_config_held(dp));
1419
1420 ratio = ds->ds_phys->ds_compressed_bytes == 0 ? 100 :
1421 (ds->ds_phys->ds_uncompressed_bytes * 100 /
1422 ds->ds_phys->ds_compressed_bytes);
1423
1424 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFRATIO, ratio);
1425 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_LOGICALREFERENCED,
1426 ds->ds_phys->ds_uncompressed_bytes);
1427
1428 if (dsl_dataset_is_snapshot(ds)) {
1429 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_COMPRESSRATIO, ratio);
1430 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USED,
1431 ds->ds_phys->ds_unique_bytes);
1432 get_clones_stat(ds, nv);
1433 } else {
1434 dsl_dir_stats(ds->ds_dir, nv);
1435 }
1436
1437 dsl_dataset_space(ds, &refd, &avail, &uobjs, &aobjs);
1438 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_AVAILABLE, avail);
1439 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFERENCED, refd);
1440
1441 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATION,
1442 ds->ds_phys->ds_creation_time);
1443 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATETXG,
1444 ds->ds_phys->ds_creation_txg);
1445 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFQUOTA,
1446 ds->ds_quota);
1447 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFRESERVATION,
1448 ds->ds_reserved);
1449 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_GUID,
1450 ds->ds_phys->ds_guid);
1451 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_UNIQUE,
1452 ds->ds_phys->ds_unique_bytes);
1453 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_OBJSETID,
1454 ds->ds_object);
1455 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USERREFS,
1456 ds->ds_userrefs);
1457 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_DEFER_DESTROY,
1458 DS_IS_DEFER_DESTROY(ds) ? 1 : 0);
1459
1460 if (ds->ds_phys->ds_prev_snap_obj != 0) {
1461 uint64_t written, comp, uncomp;
1462 dsl_pool_t *dp = ds->ds_dir->dd_pool;
1463 dsl_dataset_t *prev;
1464 int err;
1465
1466 err = dsl_dataset_hold_obj(dp,
1467 ds->ds_phys->ds_prev_snap_obj, FTAG, &prev);
1468 if (err == 0) {
1469 err = dsl_dataset_space_written(prev, ds, &written,
1470 &comp, &uncomp);
1471 dsl_dataset_rele(prev, FTAG);
1472 if (err == 0) {
1473 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_WRITTEN,
1474 written);
1475 }
1476 }
1477 }
1478
1479 }
1480
1481 void
1482 dsl_dataset_fast_stat(dsl_dataset_t *ds, dmu_objset_stats_t *stat)
1483 {
1484 dsl_pool_t *dp = ds->ds_dir->dd_pool;
1485 ASSERT(dsl_pool_config_held(dp));
1486
1487 stat->dds_creation_txg = ds->ds_phys->ds_creation_txg;
1488 stat->dds_inconsistent = ds->ds_phys->ds_flags & DS_FLAG_INCONSISTENT;
1489 stat->dds_guid = ds->ds_phys->ds_guid;
1490 stat->dds_origin[0] = '\0';
1491 if (dsl_dataset_is_snapshot(ds)) {
1492 stat->dds_is_snapshot = B_TRUE;
1493 stat->dds_num_clones = ds->ds_phys->ds_num_children - 1;
1494 } else {
1495 stat->dds_is_snapshot = B_FALSE;
1496 stat->dds_num_clones = 0;
1497
1498 if (dsl_dir_is_clone(ds->ds_dir)) {
1499 dsl_dataset_t *ods;
1500
1501 VERIFY0(dsl_dataset_hold_obj(dp,
1502 ds->ds_dir->dd_phys->dd_origin_obj, FTAG, &ods));
1503 dsl_dataset_name(ods, stat->dds_origin);
1504 dsl_dataset_rele(ods, FTAG);
1505 }
1506 }
1507 }
1508
1509 uint64_t
1510 dsl_dataset_fsid_guid(dsl_dataset_t *ds)
1511 {
1512 return (ds->ds_fsid_guid);
1513 }
1514
1515 void
1516 dsl_dataset_space(dsl_dataset_t *ds,
1517 uint64_t *refdbytesp, uint64_t *availbytesp,
1518 uint64_t *usedobjsp, uint64_t *availobjsp)
1519 {
1520 *refdbytesp = ds->ds_phys->ds_referenced_bytes;
1521 *availbytesp = dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE);
1522 if (ds->ds_reserved > ds->ds_phys->ds_unique_bytes)
1523 *availbytesp += ds->ds_reserved - ds->ds_phys->ds_unique_bytes;
1524 if (ds->ds_quota != 0) {
1525 /*
1526 * Adjust available bytes according to refquota
1527 */
1528 if (*refdbytesp < ds->ds_quota)
1529 *availbytesp = MIN(*availbytesp,
1530 ds->ds_quota - *refdbytesp);
1531 else
1532 *availbytesp = 0;
1533 }
1534 *usedobjsp = BP_GET_FILL(&ds->ds_phys->ds_bp);
1535 *availobjsp = DN_MAX_OBJECT - *usedobjsp;
1536 }
1537
1538 boolean_t
1539 dsl_dataset_modified_since_snap(dsl_dataset_t *ds, dsl_dataset_t *snap)
1540 {
1541 ASSERT(dsl_pool_config_held(ds->ds_dir->dd_pool));
1542 if (snap == NULL)
1543 return (B_FALSE);
1544 if (ds->ds_phys->ds_bp.blk_birth >
1545 snap->ds_phys->ds_creation_txg) {
1546 objset_t *os, *os_snap;
1547 /*
1548 * It may be that only the ZIL differs, because it was
1549 * reset in the head. Don't count that as being
1550 * modified.
1551 */
1552 if (dmu_objset_from_ds(ds, &os) != 0)
1553 return (B_TRUE);
1554 if (dmu_objset_from_ds(snap, &os_snap) != 0)
1555 return (B_TRUE);
1556 return (bcmp(&os->os_phys->os_meta_dnode,
1557 &os_snap->os_phys->os_meta_dnode,
1558 sizeof (os->os_phys->os_meta_dnode)) != 0);
1559 }
1560 return (B_FALSE);
1561 }
1562
1563 typedef struct dsl_dataset_rename_snapshot_arg {
1564 const char *ddrsa_fsname;
1565 const char *ddrsa_oldsnapname;
1566 const char *ddrsa_newsnapname;
1567 boolean_t ddrsa_recursive;
1568 dmu_tx_t *ddrsa_tx;
1569 } dsl_dataset_rename_snapshot_arg_t;
1570
1571 /* ARGSUSED */
1572 static int
1573 dsl_dataset_rename_snapshot_check_impl(dsl_pool_t *dp,
1574 dsl_dataset_t *hds, void *arg)
1575 {
1576 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg;
1577 int error;
1578 uint64_t val;
1579
1580 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_oldsnapname, &val);
1581 if (error != 0) {
1582 /* ignore nonexistent snapshots */
1583 return (error == ENOENT ? 0 : error);
1584 }
1585
1586 /* new name should not exist */
1587 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_newsnapname, &val);
1588 if (error == 0)
1589 error = SET_ERROR(EEXIST);
1590 else if (error == ENOENT)
1591 error = 0;
1592
1593 /* dataset name + 1 for the "@" + the new snapshot name must fit */
1594 if (dsl_dir_namelen(hds->ds_dir) + 1 +
1595 strlen(ddrsa->ddrsa_newsnapname) >= MAXNAMELEN)
1596 error = SET_ERROR(ENAMETOOLONG);
1597
1598 return (error);
1599 }
1600
1601 static int
1602 dsl_dataset_rename_snapshot_check(void *arg, dmu_tx_t *tx)
1603 {
1604 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg;
1605 dsl_pool_t *dp = dmu_tx_pool(tx);
1606 dsl_dataset_t *hds;
1607 int error;
1608
1609 error = dsl_dataset_hold(dp, ddrsa->ddrsa_fsname, FTAG, &hds);
1610 if (error != 0)
1611 return (error);
1612
1613 if (ddrsa->ddrsa_recursive) {
1614 error = dmu_objset_find_dp(dp, hds->ds_dir->dd_object,
1615 dsl_dataset_rename_snapshot_check_impl, ddrsa,
1616 DS_FIND_CHILDREN);
1617 } else {
1618 error = dsl_dataset_rename_snapshot_check_impl(dp, hds, ddrsa);
1619 }
1620 dsl_dataset_rele(hds, FTAG);
1621 return (error);
1622 }
1623
1624 static int
1625 dsl_dataset_rename_snapshot_sync_impl(dsl_pool_t *dp,
1626 dsl_dataset_t *hds, void *arg)
1627 {
1628 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg;
1629 dsl_dataset_t *ds;
1630 uint64_t val;
1631 dmu_tx_t *tx = ddrsa->ddrsa_tx;
1632 int error;
1633
1634 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_oldsnapname, &val);
1635 ASSERT(error == 0 || error == ENOENT);
1636 if (error == ENOENT) {
1637 /* ignore nonexistent snapshots */
1638 return (0);
1639 }
1640
1641 VERIFY0(dsl_dataset_hold_obj(dp, val, FTAG, &ds));
1642
1643 /* log before we change the name */
1644 spa_history_log_internal_ds(ds, "rename", tx,
1645 "-> @%s", ddrsa->ddrsa_newsnapname);
1646
1647 VERIFY0(dsl_dataset_snap_remove(hds, ddrsa->ddrsa_oldsnapname, tx));
1648 mutex_enter(&ds->ds_lock);
1649 (void) strcpy(ds->ds_snapname, ddrsa->ddrsa_newsnapname);
1650 mutex_exit(&ds->ds_lock);
1651 VERIFY0(zap_add(dp->dp_meta_objset, hds->ds_phys->ds_snapnames_zapobj,
1652 ds->ds_snapname, 8, 1, &ds->ds_object, tx));
1653
1654 dsl_dataset_rele(ds, FTAG);
1655 return (0);
1656 }
1657
1658 static void
1659 dsl_dataset_rename_snapshot_sync(void *arg, dmu_tx_t *tx)
1660 {
1661 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg;
1662 dsl_pool_t *dp = dmu_tx_pool(tx);
1663 dsl_dataset_t *hds;
1664
1665 VERIFY0(dsl_dataset_hold(dp, ddrsa->ddrsa_fsname, FTAG, &hds));
1666 ddrsa->ddrsa_tx = tx;
1667 if (ddrsa->ddrsa_recursive) {
1668 VERIFY0(dmu_objset_find_dp(dp, hds->ds_dir->dd_object,
1669 dsl_dataset_rename_snapshot_sync_impl, ddrsa,
1670 DS_FIND_CHILDREN));
1671 } else {
1672 VERIFY0(dsl_dataset_rename_snapshot_sync_impl(dp, hds, ddrsa));
1673 }
1674 dsl_dataset_rele(hds, FTAG);
1675 }
1676
1677 int
1678 dsl_dataset_rename_snapshot(const char *fsname,
1679 const char *oldsnapname, const char *newsnapname, boolean_t recursive)
1680 {
1681 #ifdef _KERNEL
1682 char *oldname, *newname;
1683 #endif
1684 int error;
1685
1686 dsl_dataset_rename_snapshot_arg_t ddrsa;
1687
1688 ddrsa.ddrsa_fsname = fsname;
1689 ddrsa.ddrsa_oldsnapname = oldsnapname;
1690 ddrsa.ddrsa_newsnapname = newsnapname;
1691 ddrsa.ddrsa_recursive = recursive;
1692
1693 error = dsl_sync_task(fsname, dsl_dataset_rename_snapshot_check,
1694 dsl_dataset_rename_snapshot_sync, &ddrsa, 1);
1695
1696 if (error)
1697 return (SET_ERROR(error));
1698
1699 #ifdef _KERNEL
1700 oldname = kmem_asprintf("%s@%s", fsname, oldsnapname);
1701 newname = kmem_asprintf("%s@%s", fsname, newsnapname);
1702 zvol_rename_minors(oldname, newname);
1703 strfree(newname);
1704 strfree(oldname);
1705 #endif
1706
1707 return (0);
1708 }
1709
1710 /*
1711 * If we're doing an ownership handoff, we need to make sure that there is
1712 * only one long hold on the dataset. We're not allowed to change anything here
1713 * so we don't permanently release the long hold or regular hold here. We want
1714 * to do this only when syncing to avoid the dataset unexpectedly going away
1715 * when we release the long hold.
1716 */
1717 static int
1718 dsl_dataset_handoff_check(dsl_dataset_t *ds, void *owner, dmu_tx_t *tx)
1719 {
1720 boolean_t held;
1721
1722 if (!dmu_tx_is_syncing(tx))
1723 return (0);
1724
1725 if (owner != NULL) {
1726 VERIFY3P(ds->ds_owner, ==, owner);
1727 dsl_dataset_long_rele(ds, owner);
1728 }
1729
1730 held = dsl_dataset_long_held(ds);
1731
1732 if (owner != NULL)
1733 dsl_dataset_long_hold(ds, owner);
1734
1735 if (held)
1736 return (SET_ERROR(EBUSY));
1737
1738 return (0);
1739 }
1740
1741 typedef struct dsl_dataset_rollback_arg {
1742 const char *ddra_fsname;
1743 void *ddra_owner;
1744 nvlist_t *ddra_result;
1745 } dsl_dataset_rollback_arg_t;
1746
1747 static int
1748 dsl_dataset_rollback_check(void *arg, dmu_tx_t *tx)
1749 {
1750 dsl_dataset_rollback_arg_t *ddra = arg;
1751 dsl_pool_t *dp = dmu_tx_pool(tx);
1752 dsl_dataset_t *ds;
1753 int64_t unused_refres_delta;
1754 int error;
1755 nvpair_t *pair;
1756 nvlist_t *proprequest, *bookmarks;
1757
1758 error = dsl_dataset_hold(dp, ddra->ddra_fsname, FTAG, &ds);
1759 if (error != 0)
1760 return (error);
1761
1762 /* must not be a snapshot */
1763 if (dsl_dataset_is_snapshot(ds)) {
1764 dsl_dataset_rele(ds, FTAG);
1765 return (SET_ERROR(EINVAL));
1766 }
1767
1768 /* must have a most recent snapshot */
1769 if (ds->ds_phys->ds_prev_snap_txg < TXG_INITIAL) {
1770 dsl_dataset_rele(ds, FTAG);
1771 return (SET_ERROR(EINVAL));
1772 }
1773
1774 /* must not have any bookmarks after the most recent snapshot */
1775 proprequest = fnvlist_alloc();
1776 fnvlist_add_boolean(proprequest, zfs_prop_to_name(ZFS_PROP_CREATETXG));
1777 bookmarks = fnvlist_alloc();
1778 error = dsl_get_bookmarks_impl(ds, proprequest, bookmarks);
1779 fnvlist_free(proprequest);
1780 if (error != 0)
1781 return (error);
1782 for (pair = nvlist_next_nvpair(bookmarks, NULL);
1783 pair != NULL; pair = nvlist_next_nvpair(bookmarks, pair)) {
1784 nvlist_t *valuenv =
1785 fnvlist_lookup_nvlist(fnvpair_value_nvlist(pair),
1786 zfs_prop_to_name(ZFS_PROP_CREATETXG));
1787 uint64_t createtxg = fnvlist_lookup_uint64(valuenv, "value");
1788 if (createtxg > ds->ds_phys->ds_prev_snap_txg) {
1789 fnvlist_free(bookmarks);
1790 dsl_dataset_rele(ds, FTAG);
1791 return (SET_ERROR(EEXIST));
1792 }
1793 }
1794 fnvlist_free(bookmarks);
1795
1796 error = dsl_dataset_handoff_check(ds, ddra->ddra_owner, tx);
1797 if (error != 0) {
1798 dsl_dataset_rele(ds, FTAG);
1799 return (error);
1800 }
1801
1802 /*
1803 * Check if the snap we are rolling back to uses more than
1804 * the refquota.
1805 */
1806 if (ds->ds_quota != 0 &&
1807 ds->ds_prev->ds_phys->ds_referenced_bytes > ds->ds_quota) {
1808 dsl_dataset_rele(ds, FTAG);
1809 return (SET_ERROR(EDQUOT));
1810 }
1811
1812 /*
1813 * When we do the clone swap, we will temporarily use more space
1814 * due to the refreservation (the head will no longer have any
1815 * unique space, so the entire amount of the refreservation will need
1816 * to be free). We will immediately destroy the clone, freeing
1817 * this space, but the freeing happens over many txg's.
1818 */
1819 unused_refres_delta = (int64_t)MIN(ds->ds_reserved,
1820 ds->ds_phys->ds_unique_bytes);
1821
1822 if (unused_refres_delta > 0 &&
1823 unused_refres_delta >
1824 dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE)) {
1825 dsl_dataset_rele(ds, FTAG);
1826 return (SET_ERROR(ENOSPC));
1827 }
1828
1829 dsl_dataset_rele(ds, FTAG);
1830 return (0);
1831 }
1832
1833 static void
1834 dsl_dataset_rollback_sync(void *arg, dmu_tx_t *tx)
1835 {
1836 dsl_dataset_rollback_arg_t *ddra = arg;
1837 dsl_pool_t *dp = dmu_tx_pool(tx);
1838 dsl_dataset_t *ds, *clone;
1839 uint64_t cloneobj;
1840 char namebuf[ZFS_MAXNAMELEN];
1841
1842 VERIFY0(dsl_dataset_hold(dp, ddra->ddra_fsname, FTAG, &ds));
1843
1844 dsl_dataset_name(ds->ds_prev, namebuf);
1845 fnvlist_add_string(ddra->ddra_result, "target", namebuf);
1846
1847 cloneobj = dsl_dataset_create_sync(ds->ds_dir, "%rollback",
1848 ds->ds_prev, DS_CREATE_FLAG_NODIRTY, kcred, tx);
1849
1850 VERIFY0(dsl_dataset_hold_obj(dp, cloneobj, FTAG, &clone));
1851
1852 dsl_dataset_clone_swap_sync_impl(clone, ds, tx);
1853 dsl_dataset_zero_zil(ds, tx);
1854
1855 dsl_destroy_head_sync_impl(clone, tx);
1856
1857 dsl_dataset_rele(clone, FTAG);
1858 dsl_dataset_rele(ds, FTAG);
1859 }
1860
1861 /*
1862 * Rolls back the given filesystem or volume to the most recent snapshot.
1863 * The name of the most recent snapshot will be returned under key "target"
1864 * in the result nvlist.
1865 *
1866 * If owner != NULL:
1867 * - The existing dataset MUST be owned by the specified owner at entry
1868 * - Upon return, dataset will still be held by the same owner, whether we
1869 * succeed or not.
1870 *
1871 * This mode is required any time the existing filesystem is mounted. See
1872 * notes above zfs_suspend_fs() for further details.
1873 */
1874 int
1875 dsl_dataset_rollback(const char *fsname, void *owner, nvlist_t *result)
1876 {
1877 dsl_dataset_rollback_arg_t ddra;
1878
1879 ddra.ddra_fsname = fsname;
1880 ddra.ddra_owner = owner;
1881 ddra.ddra_result = result;
1882
1883 return (dsl_sync_task(fsname, dsl_dataset_rollback_check,
1884 dsl_dataset_rollback_sync, &ddra, 1));
1885 }
1886
1887 struct promotenode {
1888 list_node_t link;
1889 dsl_dataset_t *ds;
1890 };
1891
1892 typedef struct dsl_dataset_promote_arg {
1893 const char *ddpa_clonename;
1894 dsl_dataset_t *ddpa_clone;
1895 list_t shared_snaps, origin_snaps, clone_snaps;
1896 dsl_dataset_t *origin_origin; /* origin of the origin */
1897 uint64_t used, comp, uncomp, unique, cloneusedsnap, originusedsnap;
1898 char *err_ds;
1899 } dsl_dataset_promote_arg_t;
1900
1901 static int snaplist_space(list_t *l, uint64_t mintxg, uint64_t *spacep);
1902 static int promote_hold(dsl_dataset_promote_arg_t *ddpa, dsl_pool_t *dp,
1903 void *tag);
1904 static void promote_rele(dsl_dataset_promote_arg_t *ddpa, void *tag);
1905
1906 static int
1907 dsl_dataset_promote_check(void *arg, dmu_tx_t *tx)
1908 {
1909 dsl_dataset_promote_arg_t *ddpa = arg;
1910 dsl_pool_t *dp = dmu_tx_pool(tx);
1911 dsl_dataset_t *hds;
1912 struct promotenode *snap;
1913 dsl_dataset_t *origin_ds;
1914 int err;
1915 uint64_t unused;
1916
1917 err = promote_hold(ddpa, dp, FTAG);
1918 if (err != 0)
1919 return (err);
1920
1921 hds = ddpa->ddpa_clone;
1922
1923 if (hds->ds_phys->ds_flags & DS_FLAG_NOPROMOTE) {
1924 promote_rele(ddpa, FTAG);
1925 return (SET_ERROR(EXDEV));
1926 }
1927
1928 /*
1929 * Compute and check the amount of space to transfer. Since this is
1930 * so expensive, don't do the preliminary check.
1931 */
1932 if (!dmu_tx_is_syncing(tx)) {
1933 promote_rele(ddpa, FTAG);
1934 return (0);
1935 }
1936
1937 snap = list_head(&ddpa->shared_snaps);
1938 origin_ds = snap->ds;
1939
1940 /* compute origin's new unique space */
1941 snap = list_tail(&ddpa->clone_snaps);
1942 ASSERT3U(snap->ds->ds_phys->ds_prev_snap_obj, ==, origin_ds->ds_object);
1943 dsl_deadlist_space_range(&snap->ds->ds_deadlist,
1944 origin_ds->ds_phys->ds_prev_snap_txg, UINT64_MAX,
1945 &ddpa->unique, &unused, &unused);
1946
1947 /*
1948 * Walk the snapshots that we are moving
1949 *
1950 * Compute space to transfer. Consider the incremental changes
1951 * to used by each snapshot:
1952 * (my used) = (prev's used) + (blocks born) - (blocks killed)
1953 * So each snapshot gave birth to:
1954 * (blocks born) = (my used) - (prev's used) + (blocks killed)
1955 * So a sequence would look like:
1956 * (uN - u(N-1) + kN) + ... + (u1 - u0 + k1) + (u0 - 0 + k0)
1957 * Which simplifies to:
1958 * uN + kN + kN-1 + ... + k1 + k0
1959 * Note however, if we stop before we reach the ORIGIN we get:
1960 * uN + kN + kN-1 + ... + kM - uM-1
1961 */
1962 ddpa->used = origin_ds->ds_phys->ds_referenced_bytes;
1963 ddpa->comp = origin_ds->ds_phys->ds_compressed_bytes;
1964 ddpa->uncomp = origin_ds->ds_phys->ds_uncompressed_bytes;
1965 for (snap = list_head(&ddpa->shared_snaps); snap;
1966 snap = list_next(&ddpa->shared_snaps, snap)) {
1967 uint64_t val, dlused, dlcomp, dluncomp;
1968 dsl_dataset_t *ds = snap->ds;
1969
1970 /*
1971 * If there are long holds, we won't be able to evict
1972 * the objset.
1973 */
1974 if (dsl_dataset_long_held(ds)) {
1975 err = SET_ERROR(EBUSY);
1976 goto out;
1977 }
1978
1979 /* Check that the snapshot name does not conflict */
1980 VERIFY0(dsl_dataset_get_snapname(ds));
1981 err = dsl_dataset_snap_lookup(hds, ds->ds_snapname, &val);
1982 if (err == 0) {
1983 (void) strcpy(ddpa->err_ds, snap->ds->ds_snapname);
1984 err = SET_ERROR(EEXIST);
1985 goto out;
1986 }
1987 if (err != ENOENT)
1988 goto out;
1989
1990 /* The very first snapshot does not have a deadlist */
1991 if (ds->ds_phys->ds_prev_snap_obj == 0)
1992 continue;
1993
1994 dsl_deadlist_space(&ds->ds_deadlist,
1995 &dlused, &dlcomp, &dluncomp);
1996 ddpa->used += dlused;
1997 ddpa->comp += dlcomp;
1998 ddpa->uncomp += dluncomp;
1999 }
2000
2001 /*
2002 * If we are a clone of a clone then we never reached ORIGIN,
2003 * so we need to subtract out the clone origin's used space.
2004 */
2005 if (ddpa->origin_origin) {
2006 ddpa->used -= ddpa->origin_origin->ds_phys->ds_referenced_bytes;
2007 ddpa->comp -= ddpa->origin_origin->ds_phys->ds_compressed_bytes;
2008 ddpa->uncomp -=
2009 ddpa->origin_origin->ds_phys->ds_uncompressed_bytes;
2010 }
2011
2012 /* Check that there is enough space here */
2013 err = dsl_dir_transfer_possible(origin_ds->ds_dir, hds->ds_dir,
2014 ddpa->used);
2015 if (err != 0)
2016 goto out;
2017
2018 /*
2019 * Compute the amounts of space that will be used by snapshots
2020 * after the promotion (for both origin and clone). For each,
2021 * it is the amount of space that will be on all of their
2022 * deadlists (that was not born before their new origin).
2023 */
2024 if (hds->ds_dir->dd_phys->dd_flags & DD_FLAG_USED_BREAKDOWN) {
2025 uint64_t space;
2026
2027 /*
2028 * Note, typically this will not be a clone of a clone,
2029 * so dd_origin_txg will be < TXG_INITIAL, so
2030 * these snaplist_space() -> dsl_deadlist_space_range()
2031 * calls will be fast because they do not have to
2032 * iterate over all bps.
2033 */
2034 snap = list_head(&ddpa->origin_snaps);
2035 err = snaplist_space(&ddpa->shared_snaps,
2036 snap->ds->ds_dir->dd_origin_txg, &ddpa->cloneusedsnap);
2037 if (err != 0)
2038 goto out;
2039
2040 err = snaplist_space(&ddpa->clone_snaps,
2041 snap->ds->ds_dir->dd_origin_txg, &space);
2042 if (err != 0)
2043 goto out;
2044 ddpa->cloneusedsnap += space;
2045 }
2046 if (origin_ds->ds_dir->dd_phys->dd_flags & DD_FLAG_USED_BREAKDOWN) {
2047 err = snaplist_space(&ddpa->origin_snaps,
2048 origin_ds->ds_phys->ds_creation_txg, &ddpa->originusedsnap);
2049 if (err != 0)
2050 goto out;
2051 }
2052
2053 out:
2054 promote_rele(ddpa, FTAG);
2055 return (err);
2056 }
2057
2058 static void
2059 dsl_dataset_promote_sync(void *arg, dmu_tx_t *tx)
2060 {
2061 dsl_dataset_promote_arg_t *ddpa = arg;
2062 dsl_pool_t *dp = dmu_tx_pool(tx);
2063 dsl_dataset_t *hds;
2064 struct promotenode *snap;
2065 dsl_dataset_t *origin_ds;
2066 dsl_dataset_t *origin_head;
2067 dsl_dir_t *dd;
2068 dsl_dir_t *odd = NULL;
2069 uint64_t oldnext_obj;
2070 int64_t delta;
2071
2072 VERIFY0(promote_hold(ddpa, dp, FTAG));
2073 hds = ddpa->ddpa_clone;
2074
2075 ASSERT0(hds->ds_phys->ds_flags & DS_FLAG_NOPROMOTE);
2076
2077 snap = list_head(&ddpa->shared_snaps);
2078 origin_ds = snap->ds;
2079 dd = hds->ds_dir;
2080
2081 snap = list_head(&ddpa->origin_snaps);
2082 origin_head = snap->ds;
2083
2084 /*
2085 * We need to explicitly open odd, since origin_ds's dd will be
2086 * changing.
2087 */
2088 VERIFY0(dsl_dir_hold_obj(dp, origin_ds->ds_dir->dd_object,
2089 NULL, FTAG, &odd));
2090
2091 /* change origin's next snap */
2092 dmu_buf_will_dirty(origin_ds->ds_dbuf, tx);
2093 oldnext_obj = origin_ds->ds_phys->ds_next_snap_obj;
2094 snap = list_tail(&ddpa->clone_snaps);
2095 ASSERT3U(snap->ds->ds_phys->ds_prev_snap_obj, ==, origin_ds->ds_object);
2096 origin_ds->ds_phys->ds_next_snap_obj = snap->ds->ds_object;
2097
2098 /* change the origin's next clone */
2099 if (origin_ds->ds_phys->ds_next_clones_obj) {
2100 dsl_dataset_remove_from_next_clones(origin_ds,
2101 snap->ds->ds_object, tx);
2102 VERIFY0(zap_add_int(dp->dp_meta_objset,
2103 origin_ds->ds_phys->ds_next_clones_obj,
2104 oldnext_obj, tx));
2105 }
2106
2107 /* change origin */
2108 dmu_buf_will_dirty(dd->dd_dbuf, tx);
2109 ASSERT3U(dd->dd_phys->dd_origin_obj, ==, origin_ds->ds_object);
2110 dd->dd_phys->dd_origin_obj = odd->dd_phys->dd_origin_obj;
2111 dd->dd_origin_txg = origin_head->ds_dir->dd_origin_txg;
2112 dmu_buf_will_dirty(odd->dd_dbuf, tx);
2113 odd->dd_phys->dd_origin_obj = origin_ds->ds_object;
2114 origin_head->ds_dir->dd_origin_txg =
2115 origin_ds->ds_phys->ds_creation_txg;
2116
2117 /* change dd_clone entries */
2118 if (spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) {
2119 VERIFY0(zap_remove_int(dp->dp_meta_objset,
2120 odd->dd_phys->dd_clones, hds->ds_object, tx));
2121 VERIFY0(zap_add_int(dp->dp_meta_objset,
2122 ddpa->origin_origin->ds_dir->dd_phys->dd_clones,
2123 hds->ds_object, tx));
2124
2125 VERIFY0(zap_remove_int(dp->dp_meta_objset,
2126 ddpa->origin_origin->ds_dir->dd_phys->dd_clones,
2127 origin_head->ds_object, tx));
2128 if (dd->dd_phys->dd_clones == 0) {
2129 dd->dd_phys->dd_clones = zap_create(dp->dp_meta_objset,
2130 DMU_OT_DSL_CLONES, DMU_OT_NONE, 0, tx);
2131 }
2132 VERIFY0(zap_add_int(dp->dp_meta_objset,
2133 dd->dd_phys->dd_clones, origin_head->ds_object, tx));
2134 }
2135
2136 /* move snapshots to this dir */
2137 for (snap = list_head(&ddpa->shared_snaps); snap;
2138 snap = list_next(&ddpa->shared_snaps, snap)) {
2139 dsl_dataset_t *ds = snap->ds;
2140
2141 /*
2142 * Property callbacks are registered to a particular
2143 * dsl_dir. Since ours is changing, evict the objset
2144 * so that they will be unregistered from the old dsl_dir.
2145 */
2146 if (ds->ds_objset) {
2147 dmu_objset_evict(ds->ds_objset);
2148 ds->ds_objset = NULL;
2149 }
2150
2151 /* move snap name entry */
2152 VERIFY0(dsl_dataset_get_snapname(ds));
2153 VERIFY0(dsl_dataset_snap_remove(origin_head,
2154 ds->ds_snapname, tx));
2155 VERIFY0(zap_add(dp->dp_meta_objset,
2156 hds->ds_phys->ds_snapnames_zapobj, ds->ds_snapname,
2157 8, 1, &ds->ds_object, tx));
2158
2159 /* change containing dsl_dir */
2160 dmu_buf_will_dirty(ds->ds_dbuf, tx);
2161 ASSERT3U(ds->ds_phys->ds_dir_obj, ==, odd->dd_object);
2162 ds->ds_phys->ds_dir_obj = dd->dd_object;
2163 ASSERT3P(ds->ds_dir, ==, odd);
2164 dsl_dir_rele(ds->ds_dir, ds);
2165 VERIFY0(dsl_dir_hold_obj(dp, dd->dd_object,
2166 NULL, ds, &ds->ds_dir));
2167
2168 /* move any clone references */
2169 if (ds->ds_phys->ds_next_clones_obj &&
2170 spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) {
2171 zap_cursor_t zc;
2172 zap_attribute_t za;
2173
2174 for (zap_cursor_init(&zc, dp->dp_meta_objset,
2175 ds->ds_phys->ds_next_clones_obj);
2176 zap_cursor_retrieve(&zc, &za) == 0;
2177 zap_cursor_advance(&zc)) {
2178 dsl_dataset_t *cnds;
2179 uint64_t o;
2180
2181 if (za.za_first_integer == oldnext_obj) {
2182 /*
2183 * We've already moved the
2184 * origin's reference.
2185 */
2186 continue;
2187 }
2188
2189 VERIFY0(dsl_dataset_hold_obj(dp,
2190 za.za_first_integer, FTAG, &cnds));
2191 o = cnds->ds_dir->dd_phys->dd_head_dataset_obj;
2192
2193 VERIFY0(zap_remove_int(dp->dp_meta_objset,
2194 odd->dd_phys->dd_clones, o, tx));
2195 VERIFY0(zap_add_int(dp->dp_meta_objset,
2196 dd->dd_phys->dd_clones, o, tx));
2197 dsl_dataset_rele(cnds, FTAG);
2198 }
2199 zap_cursor_fini(&zc);
2200 }
2201
2202 ASSERT(!dsl_prop_hascb(ds));
2203 }
2204
2205 /*
2206 * Change space accounting.
2207 * Note, pa->*usedsnap and dd_used_breakdown[SNAP] will either
2208 * both be valid, or both be 0 (resulting in delta == 0). This
2209 * is true for each of {clone,origin} independently.
2210 */
2211
2212 delta = ddpa->cloneusedsnap -
2213 dd->dd_phys->dd_used_breakdown[DD_USED_SNAP];
2214 ASSERT3S(delta, >=, 0);
2215 ASSERT3U(ddpa->used, >=, delta);
2216 dsl_dir_diduse_space(dd, DD_USED_SNAP, delta, 0, 0, tx);
2217 dsl_dir_diduse_space(dd, DD_USED_HEAD,
2218 ddpa->used - delta, ddpa->comp, ddpa->uncomp, tx);
2219
2220 delta = ddpa->originusedsnap -
2221 odd->dd_phys->dd_used_breakdown[DD_USED_SNAP];
2222 ASSERT3S(delta, <=, 0);
2223 ASSERT3U(ddpa->used, >=, -delta);
2224 dsl_dir_diduse_space(odd, DD_USED_SNAP, delta, 0, 0, tx);
2225 dsl_dir_diduse_space(odd, DD_USED_HEAD,
2226 -ddpa->used - delta, -ddpa->comp, -ddpa->uncomp, tx);
2227
2228 origin_ds->ds_phys->ds_unique_bytes = ddpa->unique;
2229
2230 /* log history record */
2231 spa_history_log_internal_ds(hds, "promote", tx, "");
2232
2233 dsl_dir_rele(odd, FTAG);
2234 promote_rele(ddpa, FTAG);
2235 }
2236
2237 /*
2238 * Make a list of dsl_dataset_t's for the snapshots between first_obj
2239 * (exclusive) and last_obj (inclusive). The list will be in reverse
2240 * order (last_obj will be the list_head()). If first_obj == 0, do all
2241 * snapshots back to this dataset's origin.
2242 */
2243 static int
2244 snaplist_make(dsl_pool_t *dp,
2245 uint64_t first_obj, uint64_t last_obj, list_t *l, void *tag)
2246 {
2247 uint64_t obj = last_obj;
2248
2249 list_create(l, sizeof (struct promotenode),
2250 offsetof(struct promotenode, link));
2251
2252 while (obj != first_obj) {
2253 dsl_dataset_t *ds;
2254 struct promotenode *snap;
2255 int err;
2256
2257 err = dsl_dataset_hold_obj(dp, obj, tag, &ds);
2258 ASSERT(err != ENOENT);
2259 if (err != 0)
2260 return (err);
2261
2262 if (first_obj == 0)
2263 first_obj = ds->ds_dir->dd_phys->dd_origin_obj;
2264
2265 snap = kmem_alloc(sizeof (*snap), KM_SLEEP);
2266 snap->ds = ds;
2267 list_insert_tail(l, snap);
2268 obj = ds->ds_phys->ds_prev_snap_obj;
2269 }
2270
2271 return (0);
2272 }
2273
2274 static int
2275 snaplist_space(list_t *l, uint64_t mintxg, uint64_t *spacep)
2276 {
2277 struct promotenode *snap;
2278
2279 *spacep = 0;
2280 for (snap = list_head(l); snap; snap = list_next(l, snap)) {
2281 uint64_t used, comp, uncomp;
2282 dsl_deadlist_space_range(&snap->ds->ds_deadlist,
2283 mintxg, UINT64_MAX, &used, &comp, &uncomp);
2284 *spacep += used;
2285 }
2286 return (0);
2287 }
2288
2289 static void
2290 snaplist_destroy(list_t *l, void *tag)
2291 {
2292 struct promotenode *snap;
2293
2294 if (l == NULL || !list_link_active(&l->list_head))
2295 return;
2296
2297 while ((snap = list_tail(l)) != NULL) {
2298 list_remove(l, snap);
2299 dsl_dataset_rele(snap->ds, tag);
2300 kmem_free(snap, sizeof (*snap));
2301 }
2302 list_destroy(l);
2303 }
2304
2305 static int
2306 promote_hold(dsl_dataset_promote_arg_t *ddpa, dsl_pool_t *dp, void *tag)
2307 {
2308 int error;
2309 dsl_dir_t *dd;
2310 struct promotenode *snap;
2311
2312 error = dsl_dataset_hold(dp, ddpa->ddpa_clonename, tag,
2313 &ddpa->ddpa_clone);
2314 if (error != 0)
2315 return (error);
2316 dd = ddpa->ddpa_clone->ds_dir;
2317
2318 if (dsl_dataset_is_snapshot(ddpa->ddpa_clone) ||
2319 !dsl_dir_is_clone(dd)) {
2320 dsl_dataset_rele(ddpa->ddpa_clone, tag);
2321 return (SET_ERROR(EINVAL));
2322 }
2323
2324 error = snaplist_make(dp, 0, dd->dd_phys->dd_origin_obj,
2325 &ddpa->shared_snaps, tag);
2326 if (error != 0)
2327 goto out;
2328
2329 error = snaplist_make(dp, 0, ddpa->ddpa_clone->ds_object,
2330 &ddpa->clone_snaps, tag);
2331 if (error != 0)
2332 goto out;
2333
2334 snap = list_head(&ddpa->shared_snaps);
2335 ASSERT3U(snap->ds->ds_object, ==, dd->dd_phys->dd_origin_obj);
2336 error = snaplist_make(dp, dd->dd_phys->dd_origin_obj,
2337 snap->ds->ds_dir->dd_phys->dd_head_dataset_obj,
2338 &ddpa->origin_snaps, tag);
2339 if (error != 0)
2340 goto out;
2341
2342 if (snap->ds->ds_dir->dd_phys->dd_origin_obj != 0) {
2343 error = dsl_dataset_hold_obj(dp,
2344 snap->ds->ds_dir->dd_phys->dd_origin_obj,
2345 tag, &ddpa->origin_origin);
2346 if (error != 0)
2347 goto out;
2348 }
2349 out:
2350 if (error != 0)
2351 promote_rele(ddpa, tag);
2352 return (error);
2353 }
2354
2355 static void
2356 promote_rele(dsl_dataset_promote_arg_t *ddpa, void *tag)
2357 {
2358 snaplist_destroy(&ddpa->shared_snaps, tag);
2359 snaplist_destroy(&ddpa->clone_snaps, tag);
2360 snaplist_destroy(&ddpa->origin_snaps, tag);
2361 if (ddpa->origin_origin != NULL)
2362 dsl_dataset_rele(ddpa->origin_origin, tag);
2363 dsl_dataset_rele(ddpa->ddpa_clone, tag);
2364 }
2365
2366 /*
2367 * Promote a clone.
2368 *
2369 * If it fails due to a conflicting snapshot name, "conflsnap" will be filled
2370 * in with the name. (It must be at least MAXNAMELEN bytes long.)
2371 */
2372 int
2373 dsl_dataset_promote(const char *name, char *conflsnap)
2374 {
2375 dsl_dataset_promote_arg_t ddpa = { 0 };
2376 uint64_t numsnaps;
2377 int error;
2378 objset_t *os;
2379
2380 /*
2381 * We will modify space proportional to the number of
2382 * snapshots. Compute numsnaps.
2383 */
2384 error = dmu_objset_hold(name, FTAG, &os);
2385 if (error != 0)
2386 return (error);
2387 error = zap_count(dmu_objset_pool(os)->dp_meta_objset,
2388 dmu_objset_ds(os)->ds_phys->ds_snapnames_zapobj, &numsnaps);
2389 dmu_objset_rele(os, FTAG);
2390 if (error != 0)
2391 return (error);
2392
2393 ddpa.ddpa_clonename = name;
2394 ddpa.err_ds = conflsnap;
2395
2396 return (dsl_sync_task(name, dsl_dataset_promote_check,
2397 dsl_dataset_promote_sync, &ddpa, 2 + numsnaps));
2398 }
2399
2400 int
2401 dsl_dataset_clone_swap_check_impl(dsl_dataset_t *clone,
2402 dsl_dataset_t *origin_head, boolean_t force, void *owner, dmu_tx_t *tx)
2403 {
2404 int64_t unused_refres_delta;
2405
2406 /* they should both be heads */
2407 if (dsl_dataset_is_snapshot(clone) ||
2408 dsl_dataset_is_snapshot(origin_head))
2409 return (SET_ERROR(EINVAL));
2410
2411 /* if we are not forcing, the branch point should be just before them */
2412 if (!force && clone->ds_prev != origin_head->ds_prev)
2413 return (SET_ERROR(EINVAL));
2414
2415 /* clone should be the clone (unless they are unrelated) */
2416 if (clone->ds_prev != NULL &&
2417 clone->ds_prev != clone->ds_dir->dd_pool->dp_origin_snap &&
2418 origin_head->ds_dir != clone->ds_prev->ds_dir)
2419 return (SET_ERROR(EINVAL));
2420
2421 /* the clone should be a child of the origin */
2422 if (clone->ds_dir->dd_parent != origin_head->ds_dir)
2423 return (SET_ERROR(EINVAL));
2424
2425 /* origin_head shouldn't be modified unless 'force' */
2426 if (!force &&
2427 dsl_dataset_modified_since_snap(origin_head, origin_head->ds_prev))
2428 return (SET_ERROR(ETXTBSY));
2429
2430 /* origin_head should have no long holds (e.g. is not mounted) */
2431 if (dsl_dataset_handoff_check(origin_head, owner, tx))
2432 return (SET_ERROR(EBUSY));
2433
2434 /* check amount of any unconsumed refreservation */
2435 unused_refres_delta =
2436 (int64_t)MIN(origin_head->ds_reserved,
2437 origin_head->ds_phys->ds_unique_bytes) -
2438 (int64_t)MIN(origin_head->ds_reserved,
2439 clone->ds_phys->ds_unique_bytes);
2440
2441 if (unused_refres_delta > 0 &&
2442 unused_refres_delta >
2443 dsl_dir_space_available(origin_head->ds_dir, NULL, 0, TRUE))
2444 return (SET_ERROR(ENOSPC));
2445
2446 /* clone can't be over the head's refquota */
2447 if (origin_head->ds_quota != 0 &&
2448 clone->ds_phys->ds_referenced_bytes > origin_head->ds_quota)
2449 return (SET_ERROR(EDQUOT));
2450
2451 return (0);
2452 }
2453
2454 void
2455 dsl_dataset_clone_swap_sync_impl(dsl_dataset_t *clone,
2456 dsl_dataset_t *origin_head, dmu_tx_t *tx)
2457 {
2458 dsl_pool_t *dp = dmu_tx_pool(tx);
2459 int64_t unused_refres_delta;
2460
2461 ASSERT(clone->ds_reserved == 0);
2462 ASSERT(origin_head->ds_quota == 0 ||
2463 clone->ds_phys->ds_unique_bytes <= origin_head->ds_quota);
2464 ASSERT3P(clone->ds_prev, ==, origin_head->ds_prev);
2465
2466 dmu_buf_will_dirty(clone->ds_dbuf, tx);
2467 dmu_buf_will_dirty(origin_head->ds_dbuf, tx);
2468
2469 if (clone->ds_objset != NULL) {
2470 dmu_objset_evict(clone->ds_objset);
2471 clone->ds_objset = NULL;
2472 }
2473
2474 if (origin_head->ds_objset != NULL) {
2475 dmu_objset_evict(origin_head->ds_objset);
2476 origin_head->ds_objset = NULL;
2477 }
2478
2479 unused_refres_delta =
2480 (int64_t)MIN(origin_head->ds_reserved,
2481 origin_head->ds_phys->ds_unique_bytes) -
2482 (int64_t)MIN(origin_head->ds_reserved,
2483 clone->ds_phys->ds_unique_bytes);
2484
2485 /*
2486 * Reset origin's unique bytes, if it exists.
2487 */
2488 if (clone->ds_prev) {
2489 dsl_dataset_t *origin = clone->ds_prev;
2490 uint64_t comp, uncomp;
2491
2492 dmu_buf_will_dirty(origin->ds_dbuf, tx);
2493 dsl_deadlist_space_range(&clone->ds_deadlist,
2494 origin->ds_phys->ds_prev_snap_txg, UINT64_MAX,
2495 &origin->ds_phys->ds_unique_bytes, &comp, &uncomp);
2496 }
2497
2498 /* swap blkptrs */
2499 {
2500 blkptr_t tmp;
2501 tmp = origin_head->ds_phys->ds_bp;
2502 origin_head->ds_phys->ds_bp = clone->ds_phys->ds_bp;
2503 clone->ds_phys->ds_bp = tmp;
2504 }
2505
2506 /* set dd_*_bytes */
2507 {
2508 int64_t dused, dcomp, duncomp;
2509 uint64_t cdl_used, cdl_comp, cdl_uncomp;
2510 uint64_t odl_used, odl_comp, odl_uncomp;
2511
2512 ASSERT3U(clone->ds_dir->dd_phys->
2513 dd_used_breakdown[DD_USED_SNAP], ==, 0);
2514
2515 dsl_deadlist_space(&clone->ds_deadlist,
2516 &cdl_used, &cdl_comp, &cdl_uncomp);
2517 dsl_deadlist_space(&origin_head->ds_deadlist,
2518 &odl_used, &odl_comp, &odl_uncomp);
2519
2520 dused = clone->ds_phys->ds_referenced_bytes + cdl_used -
2521 (origin_head->ds_phys->ds_referenced_bytes + odl_used);
2522 dcomp = clone->ds_phys->ds_compressed_bytes + cdl_comp -
2523 (origin_head->ds_phys->ds_compressed_bytes + odl_comp);
2524 duncomp = clone->ds_phys->ds_uncompressed_bytes +
2525 cdl_uncomp -
2526 (origin_head->ds_phys->ds_uncompressed_bytes + odl_uncomp);
2527
2528 dsl_dir_diduse_space(origin_head->ds_dir, DD_USED_HEAD,
2529 dused, dcomp, duncomp, tx);
2530 dsl_dir_diduse_space(clone->ds_dir, DD_USED_HEAD,
2531 -dused, -dcomp, -duncomp, tx);
2532
2533 /*
2534 * The difference in the space used by snapshots is the
2535 * difference in snapshot space due to the head's
2536 * deadlist (since that's the only thing that's
2537 * changing that affects the snapused).
2538 */
2539 dsl_deadlist_space_range(&clone->ds_deadlist,
2540 origin_head->ds_dir->dd_origin_txg, UINT64_MAX,
2541 &cdl_used, &cdl_comp, &cdl_uncomp);
2542 dsl_deadlist_space_range(&origin_head->ds_deadlist,
2543 origin_head->ds_dir->dd_origin_txg, UINT64_MAX,
2544 &odl_used, &odl_comp, &odl_uncomp);
2545 dsl_dir_transfer_space(origin_head->ds_dir, cdl_used - odl_used,
2546 DD_USED_HEAD, DD_USED_SNAP, tx);
2547 }
2548
2549 /* swap ds_*_bytes */
2550 SWITCH64(origin_head->ds_phys->ds_referenced_bytes,
2551 clone->ds_phys->ds_referenced_bytes);
2552 SWITCH64(origin_head->ds_phys->ds_compressed_bytes,
2553 clone->ds_phys->ds_compressed_bytes);
2554 SWITCH64(origin_head->ds_phys->ds_uncompressed_bytes,
2555 clone->ds_phys->ds_uncompressed_bytes);
2556 SWITCH64(origin_head->ds_phys->ds_unique_bytes,
2557 clone->ds_phys->ds_unique_bytes);
2558
2559 /* apply any parent delta for change in unconsumed refreservation */
2560 dsl_dir_diduse_space(origin_head->ds_dir, DD_USED_REFRSRV,
2561 unused_refres_delta, 0, 0, tx);
2562
2563 /*
2564 * Swap deadlists.
2565 */
2566 dsl_deadlist_close(&clone->ds_deadlist);
2567 dsl_deadlist_close(&origin_head->ds_deadlist);
2568 SWITCH64(origin_head->ds_phys->ds_deadlist_obj,
2569 clone->ds_phys->ds_deadlist_obj);
2570 dsl_deadlist_open(&clone->ds_deadlist, dp->dp_meta_objset,
2571 clone->ds_phys->ds_deadlist_obj);
2572 dsl_deadlist_open(&origin_head->ds_deadlist, dp->dp_meta_objset,
2573 origin_head->ds_phys->ds_deadlist_obj);
2574
2575 dsl_scan_ds_clone_swapped(origin_head, clone, tx);
2576
2577 spa_history_log_internal_ds(clone, "clone swap", tx,
2578 "parent=%s", origin_head->ds_dir->dd_myname);
2579 }
2580
2581 /*
2582 * Given a pool name and a dataset object number in that pool,
2583 * return the name of that dataset.
2584 */
2585 int
2586 dsl_dsobj_to_dsname(char *pname, uint64_t obj, char *buf)
2587 {
2588 dsl_pool_t *dp;
2589 dsl_dataset_t *ds;
2590 int error;
2591
2592 error = dsl_pool_hold(pname, FTAG, &dp);
2593 if (error != 0)
2594 return (error);
2595
2596 error = dsl_dataset_hold_obj(dp, obj, FTAG, &ds);
2597 if (error == 0) {
2598 dsl_dataset_name(ds, buf);
2599 dsl_dataset_rele(ds, FTAG);
2600 }
2601 dsl_pool_rele(dp, FTAG);
2602
2603 return (error);
2604 }
2605
2606 int
2607 dsl_dataset_check_quota(dsl_dataset_t *ds, boolean_t check_quota,
2608 uint64_t asize, uint64_t inflight, uint64_t *used, uint64_t *ref_rsrv)
2609 {
2610 int error = 0;
2611
2612 ASSERT3S(asize, >, 0);
2613
2614 /*
2615 * *ref_rsrv is the portion of asize that will come from any
2616 * unconsumed refreservation space.
2617 */
2618 *ref_rsrv = 0;
2619
2620 mutex_enter(&ds->ds_lock);
2621 /*
2622 * Make a space adjustment for reserved bytes.
2623 */
2624 if (ds->ds_reserved > ds->ds_phys->ds_unique_bytes) {
2625 ASSERT3U(*used, >=,
2626 ds->ds_reserved - ds->ds_phys->ds_unique_bytes);
2627 *used -= (ds->ds_reserved - ds->ds_phys->ds_unique_bytes);
2628 *ref_rsrv =
2629 asize - MIN(asize, parent_delta(ds, asize + inflight));
2630 }
2631
2632 if (!check_quota || ds->ds_quota == 0) {
2633 mutex_exit(&ds->ds_lock);
2634 return (0);
2635 }
2636 /*
2637 * If they are requesting more space, and our current estimate
2638 * is over quota, they get to try again unless the actual
2639 * on-disk is over quota and there are no pending changes (which
2640 * may free up space for us).
2641 */
2642 if (ds->ds_phys->ds_referenced_bytes + inflight >= ds->ds_quota) {
2643 if (inflight > 0 ||
2644 ds->ds_phys->ds_referenced_bytes < ds->ds_quota)
2645 error = SET_ERROR(ERESTART);
2646 else
2647 error = SET_ERROR(EDQUOT);
2648 }
2649 mutex_exit(&ds->ds_lock);
2650
2651 return (error);
2652 }
2653
2654 typedef struct dsl_dataset_set_qr_arg {
2655 const char *ddsqra_name;
2656 zprop_source_t ddsqra_source;
2657 uint64_t ddsqra_value;
2658 } dsl_dataset_set_qr_arg_t;
2659
2660
2661 /* ARGSUSED */
2662 static int
2663 dsl_dataset_set_refquota_check(void *arg, dmu_tx_t *tx)
2664 {
2665 dsl_dataset_set_qr_arg_t *ddsqra = arg;
2666 dsl_pool_t *dp = dmu_tx_pool(tx);
2667 dsl_dataset_t *ds;
2668 int error;
2669 uint64_t newval;
2670
2671 if (spa_version(dp->dp_spa) < SPA_VERSION_REFQUOTA)
2672 return (SET_ERROR(ENOTSUP));
2673
2674 error = dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds);
2675 if (error != 0)
2676 return (error);
2677
2678 if (dsl_dataset_is_snapshot(ds)) {
2679 dsl_dataset_rele(ds, FTAG);
2680 return (SET_ERROR(EINVAL));
2681 }
2682
2683 error = dsl_prop_predict(ds->ds_dir,
2684 zfs_prop_to_name(ZFS_PROP_REFQUOTA),
2685 ddsqra->ddsqra_source, ddsqra->ddsqra_value, &newval);
2686 if (error != 0) {
2687 dsl_dataset_rele(ds, FTAG);
2688 return (error);
2689 }
2690
2691 if (newval == 0) {
2692 dsl_dataset_rele(ds, FTAG);
2693 return (0);
2694 }
2695
2696 if (newval < ds->ds_phys->ds_referenced_bytes ||
2697 newval < ds->ds_reserved) {
2698 dsl_dataset_rele(ds, FTAG);
2699 return (SET_ERROR(ENOSPC));
2700 }
2701
2702 dsl_dataset_rele(ds, FTAG);
2703 return (0);
2704 }
2705
2706 static void
2707 dsl_dataset_set_refquota_sync(void *arg, dmu_tx_t *tx)
2708 {
2709 dsl_dataset_set_qr_arg_t *ddsqra = arg;
2710 dsl_pool_t *dp = dmu_tx_pool(tx);
2711 dsl_dataset_t *ds;
2712 uint64_t newval;
2713
2714 VERIFY0(dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds));
2715
2716 dsl_prop_set_sync_impl(ds,
2717 zfs_prop_to_name(ZFS_PROP_REFQUOTA),
2718 ddsqra->ddsqra_source, sizeof (ddsqra->ddsqra_value), 1,
2719 &ddsqra->ddsqra_value, tx);
2720
2721 VERIFY0(dsl_prop_get_int_ds(ds,
2722 zfs_prop_to_name(ZFS_PROP_REFQUOTA), &newval));
2723
2724 if (ds->ds_quota != newval) {
2725 dmu_buf_will_dirty(ds->ds_dbuf, tx);
2726 ds->ds_quota = newval;
2727 }
2728 dsl_dataset_rele(ds, FTAG);
2729 }
2730
2731 int
2732 dsl_dataset_set_refquota(const char *dsname, zprop_source_t source,
2733 uint64_t refquota)
2734 {
2735 dsl_dataset_set_qr_arg_t ddsqra;
2736
2737 ddsqra.ddsqra_name = dsname;
2738 ddsqra.ddsqra_source = source;
2739 ddsqra.ddsqra_value = refquota;
2740
2741 return (dsl_sync_task(dsname, dsl_dataset_set_refquota_check,
2742 dsl_dataset_set_refquota_sync, &ddsqra, 0));
2743 }
2744
2745 static int
2746 dsl_dataset_set_refreservation_check(void *arg, dmu_tx_t *tx)
2747 {
2748 dsl_dataset_set_qr_arg_t *ddsqra = arg;
2749 dsl_pool_t *dp = dmu_tx_pool(tx);
2750 dsl_dataset_t *ds;
2751 int error;
2752 uint64_t newval, unique;
2753
2754 if (spa_version(dp->dp_spa) < SPA_VERSION_REFRESERVATION)
2755 return (SET_ERROR(ENOTSUP));
2756
2757 error = dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds);
2758 if (error != 0)
2759 return (error);
2760
2761 if (dsl_dataset_is_snapshot(ds)) {
2762 dsl_dataset_rele(ds, FTAG);
2763 return (SET_ERROR(EINVAL));
2764 }
2765
2766 error = dsl_prop_predict(ds->ds_dir,
2767 zfs_prop_to_name(ZFS_PROP_REFRESERVATION),
2768 ddsqra->ddsqra_source, ddsqra->ddsqra_value, &newval);
2769 if (error != 0) {
2770 dsl_dataset_rele(ds, FTAG);
2771 return (error);
2772 }
2773
2774 /*
2775 * If we are doing the preliminary check in open context, the
2776 * space estimates may be inaccurate.
2777 */
2778 if (!dmu_tx_is_syncing(tx)) {
2779 dsl_dataset_rele(ds, FTAG);
2780 return (0);
2781 }
2782
2783 mutex_enter(&ds->ds_lock);
2784 if (!DS_UNIQUE_IS_ACCURATE(ds))
2785 dsl_dataset_recalc_head_uniq(ds);
2786 unique = ds->ds_phys->ds_unique_bytes;
2787 mutex_exit(&ds->ds_lock);
2788
2789 if (MAX(unique, newval) > MAX(unique, ds->ds_reserved)) {
2790 uint64_t delta = MAX(unique, newval) -
2791 MAX(unique, ds->ds_reserved);
2792
2793 if (delta >
2794 dsl_dir_space_available(ds->ds_dir, NULL, 0, B_TRUE) ||
2795 (ds->ds_quota > 0 && newval > ds->ds_quota)) {
2796 dsl_dataset_rele(ds, FTAG);
2797 return (SET_ERROR(ENOSPC));
2798 }
2799 }
2800
2801 dsl_dataset_rele(ds, FTAG);
2802 return (0);
2803 }
2804
2805 void
2806 dsl_dataset_set_refreservation_sync_impl(dsl_dataset_t *ds,
2807 zprop_source_t source, uint64_t value, dmu_tx_t *tx)
2808 {
2809 uint64_t newval;
2810 uint64_t unique;
2811 int64_t delta;
2812
2813 dsl_prop_set_sync_impl(ds, zfs_prop_to_name(ZFS_PROP_REFRESERVATION),
2814 source, sizeof (value), 1, &value, tx);
2815
2816 VERIFY0(dsl_prop_get_int_ds(ds,
2817 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), &newval));
2818
2819 dmu_buf_will_dirty(ds->ds_dbuf, tx);
2820 mutex_enter(&ds->ds_dir->dd_lock);
2821 mutex_enter(&ds->ds_lock);
2822 ASSERT(DS_UNIQUE_IS_ACCURATE(ds));
2823 unique = ds->ds_phys->ds_unique_bytes;
2824 delta = MAX(0, (int64_t)(newval - unique)) -
2825 MAX(0, (int64_t)(ds->ds_reserved - unique));
2826 ds->ds_reserved = newval;
2827 mutex_exit(&ds->ds_lock);
2828
2829 dsl_dir_diduse_space(ds->ds_dir, DD_USED_REFRSRV, delta, 0, 0, tx);
2830 mutex_exit(&ds->ds_dir->dd_lock);
2831 }
2832
2833 static void
2834 dsl_dataset_set_refreservation_sync(void *arg, dmu_tx_t *tx)
2835 {
2836 dsl_dataset_set_qr_arg_t *ddsqra = arg;
2837 dsl_pool_t *dp = dmu_tx_pool(tx);
2838 dsl_dataset_t *ds;
2839
2840 VERIFY0(dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds));
2841 dsl_dataset_set_refreservation_sync_impl(ds,
2842 ddsqra->ddsqra_source, ddsqra->ddsqra_value, tx);
2843 dsl_dataset_rele(ds, FTAG);
2844 }
2845
2846 int
2847 dsl_dataset_set_refreservation(const char *dsname, zprop_source_t source,
2848 uint64_t refreservation)
2849 {
2850 dsl_dataset_set_qr_arg_t ddsqra;
2851
2852 ddsqra.ddsqra_name = dsname;
2853 ddsqra.ddsqra_source = source;
2854 ddsqra.ddsqra_value = refreservation;
2855
2856 return (dsl_sync_task(dsname, dsl_dataset_set_refreservation_check,
2857 dsl_dataset_set_refreservation_sync, &ddsqra, 0));
2858 }
2859
2860 /*
2861 * Return (in *usedp) the amount of space written in new that is not
2862 * present in oldsnap. New may be a snapshot or the head. Old must be
2863 * a snapshot before new, in new's filesystem (or its origin). If not then
2864 * fail and return EINVAL.
2865 *
2866 * The written space is calculated by considering two components: First, we
2867 * ignore any freed space, and calculate the written as new's used space
2868 * minus old's used space. Next, we add in the amount of space that was freed
2869 * between the two snapshots, thus reducing new's used space relative to old's.
2870 * Specifically, this is the space that was born before old->ds_creation_txg,
2871 * and freed before new (ie. on new's deadlist or a previous deadlist).
2872 *
2873 * space freed [---------------------]
2874 * snapshots ---O-------O--------O-------O------
2875 * oldsnap new
2876 */
2877 int
2878 dsl_dataset_space_written(dsl_dataset_t *oldsnap, dsl_dataset_t *new,
2879 uint64_t *usedp, uint64_t *compp, uint64_t *uncompp)
2880 {
2881 int err = 0;
2882 uint64_t snapobj;
2883 dsl_pool_t *dp = new->ds_dir->dd_pool;
2884
2885 ASSERT(dsl_pool_config_held(dp));
2886
2887 *usedp = 0;
2888 *usedp += new->ds_phys->ds_referenced_bytes;
2889 *usedp -= oldsnap->ds_phys->ds_referenced_bytes;
2890
2891 *compp = 0;
2892 *compp += new->ds_phys->ds_compressed_bytes;
2893 *compp -= oldsnap->ds_phys->ds_compressed_bytes;
2894
2895 *uncompp = 0;
2896 *uncompp += new->ds_phys->ds_uncompressed_bytes;
2897 *uncompp -= oldsnap->ds_phys->ds_uncompressed_bytes;
2898
2899 snapobj = new->ds_object;
2900 while (snapobj != oldsnap->ds_object) {
2901 dsl_dataset_t *snap;
2902 uint64_t used, comp, uncomp;
2903
2904 if (snapobj == new->ds_object) {
2905 snap = new;
2906 } else {
2907 err = dsl_dataset_hold_obj(dp, snapobj, FTAG, &snap);
2908 if (err != 0)
2909 break;
2910 }
2911
2912 if (snap->ds_phys->ds_prev_snap_txg ==
2913 oldsnap->ds_phys->ds_creation_txg) {
2914 /*
2915 * The blocks in the deadlist can not be born after
2916 * ds_prev_snap_txg, so get the whole deadlist space,
2917 * which is more efficient (especially for old-format
2918 * deadlists). Unfortunately the deadlist code
2919 * doesn't have enough information to make this
2920 * optimization itself.
2921 */
2922 dsl_deadlist_space(&snap->ds_deadlist,
2923 &used, &comp, &uncomp);
2924 } else {
2925 dsl_deadlist_space_range(&snap->ds_deadlist,
2926 0, oldsnap->ds_phys->ds_creation_txg,
2927 &used, &comp, &uncomp);
2928 }
2929 *usedp += used;
2930 *compp += comp;
2931 *uncompp += uncomp;
2932
2933 /*
2934 * If we get to the beginning of the chain of snapshots
2935 * (ds_prev_snap_obj == 0) before oldsnap, then oldsnap
2936 * was not a snapshot of/before new.
2937 */
2938 snapobj = snap->ds_phys->ds_prev_snap_obj;
2939 if (snap != new)
2940 dsl_dataset_rele(snap, FTAG);
2941 if (snapobj == 0) {
2942 err = SET_ERROR(EINVAL);
2943 break;
2944 }
2945
2946 }
2947 return (err);
2948 }
2949
2950 /*
2951 * Return (in *usedp) the amount of space that will be reclaimed if firstsnap,
2952 * lastsnap, and all snapshots in between are deleted.
2953 *
2954 * blocks that would be freed [---------------------------]
2955 * snapshots ---O-------O--------O-------O--------O
2956 * firstsnap lastsnap
2957 *
2958 * This is the set of blocks that were born after the snap before firstsnap,
2959 * (birth > firstsnap->prev_snap_txg) and died before the snap after the
2960 * last snap (ie, is on lastsnap->ds_next->ds_deadlist or an earlier deadlist).
2961 * We calculate this by iterating over the relevant deadlists (from the snap
2962 * after lastsnap, backward to the snap after firstsnap), summing up the
2963 * space on the deadlist that was born after the snap before firstsnap.
2964 */
2965 int
2966 dsl_dataset_space_wouldfree(dsl_dataset_t *firstsnap,
2967 dsl_dataset_t *lastsnap,
2968 uint64_t *usedp, uint64_t *compp, uint64_t *uncompp)
2969 {
2970 int err = 0;
2971 uint64_t snapobj;
2972 dsl_pool_t *dp = firstsnap->ds_dir->dd_pool;
2973
2974 ASSERT(dsl_dataset_is_snapshot(firstsnap));
2975 ASSERT(dsl_dataset_is_snapshot(lastsnap));
2976
2977 /*
2978 * Check that the snapshots are in the same dsl_dir, and firstsnap
2979 * is before lastsnap.
2980 */
2981 if (firstsnap->ds_dir != lastsnap->ds_dir ||
2982 firstsnap->ds_phys->ds_creation_txg >
2983 lastsnap->ds_phys->ds_creation_txg)
2984 return (SET_ERROR(EINVAL));
2985
2986 *usedp = *compp = *uncompp = 0;
2987
2988 snapobj = lastsnap->ds_phys->ds_next_snap_obj;
2989 while (snapobj != firstsnap->ds_object) {
2990 dsl_dataset_t *ds;
2991 uint64_t used, comp, uncomp;
2992
2993 err = dsl_dataset_hold_obj(dp, snapobj, FTAG, &ds);
2994 if (err != 0)
2995 break;
2996
2997 dsl_deadlist_space_range(&ds->ds_deadlist,
2998 firstsnap->ds_phys->ds_prev_snap_txg, UINT64_MAX,
2999 &used, &comp, &uncomp);
3000 *usedp += used;
3001 *compp += comp;
3002 *uncompp += uncomp;
3003
3004 snapobj = ds->ds_phys->ds_prev_snap_obj;
3005 ASSERT3U(snapobj, !=, 0);
3006 dsl_dataset_rele(ds, FTAG);
3007 }
3008 return (err);
3009 }
3010
3011 /*
3012 * Return TRUE if 'earlier' is an earlier snapshot in 'later's timeline.
3013 * For example, they could both be snapshots of the same filesystem, and
3014 * 'earlier' is before 'later'. Or 'earlier' could be the origin of
3015 * 'later's filesystem. Or 'earlier' could be an older snapshot in the origin's
3016 * filesystem. Or 'earlier' could be the origin's origin.
3017 *
3018 * If non-zero, earlier_txg is used instead of earlier's ds_creation_txg.
3019 */
3020 boolean_t
3021 dsl_dataset_is_before(dsl_dataset_t *later, dsl_dataset_t *earlier,
3022 uint64_t earlier_txg)
3023 {
3024 dsl_pool_t *dp = later->ds_dir->dd_pool;
3025 int error;
3026 boolean_t ret;
3027 dsl_dataset_t *origin;
3028
3029 ASSERT(dsl_pool_config_held(dp));
3030 ASSERT(dsl_dataset_is_snapshot(earlier) || earlier_txg != 0);
3031
3032 if (earlier_txg == 0)
3033 earlier_txg = earlier->ds_phys->ds_creation_txg;
3034
3035 if (dsl_dataset_is_snapshot(later) &&
3036 earlier_txg >= later->ds_phys->ds_creation_txg)
3037 return (B_FALSE);
3038
3039 if (later->ds_dir == earlier->ds_dir)
3040 return (B_TRUE);
3041 if (!dsl_dir_is_clone(later->ds_dir))
3042 return (B_FALSE);
3043
3044 if (later->ds_dir->dd_phys->dd_origin_obj == earlier->ds_object)
3045 return (B_TRUE);
3046 error = dsl_dataset_hold_obj(dp,
3047 later->ds_dir->dd_phys->dd_origin_obj, FTAG, &origin);
3048 if (error != 0)
3049 return (B_FALSE);
3050 ret = dsl_dataset_is_before(origin, earlier, earlier_txg);
3051 dsl_dataset_rele(origin, FTAG);
3052 return (ret);
3053 }
3054
3055
3056 void
3057 dsl_dataset_zapify(dsl_dataset_t *ds, dmu_tx_t *tx)
3058 {
3059 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
3060 dmu_object_zapify(mos, ds->ds_object, DMU_OT_DSL_DATASET, tx);
3061 }
3062
3063 #if defined(_KERNEL) && defined(HAVE_SPL)
3064 EXPORT_SYMBOL(dsl_dataset_hold);
3065 EXPORT_SYMBOL(dsl_dataset_hold_obj);
3066 EXPORT_SYMBOL(dsl_dataset_own);
3067 EXPORT_SYMBOL(dsl_dataset_own_obj);
3068 EXPORT_SYMBOL(dsl_dataset_name);
3069 EXPORT_SYMBOL(dsl_dataset_rele);
3070 EXPORT_SYMBOL(dsl_dataset_disown);
3071 EXPORT_SYMBOL(dsl_dataset_tryown);
3072 EXPORT_SYMBOL(dsl_dataset_create_sync);
3073 EXPORT_SYMBOL(dsl_dataset_create_sync_dd);
3074 EXPORT_SYMBOL(dsl_dataset_snapshot_check);
3075 EXPORT_SYMBOL(dsl_dataset_snapshot_sync);
3076 EXPORT_SYMBOL(dsl_dataset_promote);
3077 EXPORT_SYMBOL(dsl_dataset_user_hold);
3078 EXPORT_SYMBOL(dsl_dataset_user_release);
3079 EXPORT_SYMBOL(dsl_dataset_get_holds);
3080 EXPORT_SYMBOL(dsl_dataset_get_blkptr);
3081 EXPORT_SYMBOL(dsl_dataset_set_blkptr);
3082 EXPORT_SYMBOL(dsl_dataset_get_spa);
3083 EXPORT_SYMBOL(dsl_dataset_modified_since_snap);
3084 EXPORT_SYMBOL(dsl_dataset_space_written);
3085 EXPORT_SYMBOL(dsl_dataset_space_wouldfree);
3086 EXPORT_SYMBOL(dsl_dataset_sync);
3087 EXPORT_SYMBOL(dsl_dataset_block_born);
3088 EXPORT_SYMBOL(dsl_dataset_block_kill);
3089 EXPORT_SYMBOL(dsl_dataset_block_freeable);
3090 EXPORT_SYMBOL(dsl_dataset_prev_snap_txg);
3091 EXPORT_SYMBOL(dsl_dataset_dirty);
3092 EXPORT_SYMBOL(dsl_dataset_stats);
3093 EXPORT_SYMBOL(dsl_dataset_fast_stat);
3094 EXPORT_SYMBOL(dsl_dataset_space);
3095 EXPORT_SYMBOL(dsl_dataset_fsid_guid);
3096 EXPORT_SYMBOL(dsl_dsobj_to_dsname);
3097 EXPORT_SYMBOL(dsl_dataset_check_quota);
3098 EXPORT_SYMBOL(dsl_dataset_clone_swap_check_impl);
3099 EXPORT_SYMBOL(dsl_dataset_clone_swap_sync_impl);
3100 #endif
Mirror of ZFSOnLinux for Debian