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) 2011, 2015 by Delphix. All rights reserved.
24 * Copyright (c) 2014, Joyent, Inc. All rights reserved.
25 * Copyright (c) 2014 RackTop Systems.
26 * Copyright (c) 2014 Spectra Logic Corporation, All rights reserved.
27 */
28
29 #include <sys/dmu_objset.h>
30 #include <sys/dsl_dataset.h>
31 #include <sys/dsl_dir.h>
32 #include <sys/dsl_prop.h>
33 #include <sys/dsl_synctask.h>
34 #include <sys/dmu_traverse.h>
35 #include <sys/dmu_impl.h>
36 #include <sys/dmu_tx.h>
37 #include <sys/arc.h>
38 #include <sys/zio.h>
39 #include <sys/zap.h>
40 #include <sys/zfeature.h>
41 #include <sys/unique.h>
42 #include <sys/zfs_context.h>
43 #include <sys/zfs_ioctl.h>
44 #include <sys/spa.h>
45 #include <sys/zfs_znode.h>
46 #include <sys/zfs_onexit.h>
47 #include <sys/zvol.h>
48 #include <sys/dsl_scan.h>
49 #include <sys/dsl_deadlist.h>
50 #include <sys/dsl_destroy.h>
51 #include <sys/dsl_userhold.h>
52 #include <sys/dsl_bookmark.h>
53 #include <sys/dmu_send.h>
54 #include <sys/zio_checksum.h>
55 #include <sys/zio_compress.h>
56 #include <zfs_fletcher.h>
57
58 /*
59 * The SPA supports block sizes up to 16MB. However, very large blocks
60 * can have an impact on i/o latency (e.g. tying up a spinning disk for
61 * ~300ms), and also potentially on the memory allocator. Therefore,
62 * we do not allow the recordsize to be set larger than zfs_max_recordsize
63 * (default 1MB). Larger blocks can be created by changing this tunable,
64 * and pools with larger blocks can always be imported and used, regardless
65 * of this setting.
66 */
67 int zfs_max_recordsize = 1 * 1024 * 1024;
68
69 #define SWITCH64(x, y) \
70 { \
71 uint64_t __tmp = (x); \
72 (x) = (y); \
73 (y) = __tmp; \
74 }
75
76 #define DS_REF_MAX (1ULL << 62)
77
78 extern inline dsl_dataset_phys_t *dsl_dataset_phys(dsl_dataset_t *ds);
79
80 /*
81 * Figure out how much of this delta should be propogated to the dsl_dir
82 * layer. If there's a refreservation, that space has already been
83 * partially accounted for in our ancestors.
84 */
85 static int64_t
86 parent_delta(dsl_dataset_t *ds, int64_t delta)
87 {
88 dsl_dataset_phys_t *ds_phys;
89 uint64_t old_bytes, new_bytes;
90
91 if (ds->ds_reserved == 0)
92 return (delta);
93
94 ds_phys = dsl_dataset_phys(ds);
95 old_bytes = MAX(ds_phys->ds_unique_bytes, ds->ds_reserved);
96 new_bytes = MAX(ds_phys->ds_unique_bytes + delta, ds->ds_reserved);
97
98 ASSERT3U(ABS((int64_t)(new_bytes - old_bytes)), <=, ABS(delta));
99 return (new_bytes - old_bytes);
100 }
101
102 void
103 dsl_dataset_block_born(dsl_dataset_t *ds, const blkptr_t *bp, dmu_tx_t *tx)
104 {
105 int used = bp_get_dsize_sync(tx->tx_pool->dp_spa, bp);
106 int compressed = BP_GET_PSIZE(bp);
107 int uncompressed = BP_GET_UCSIZE(bp);
108 int64_t delta;
109
110 dprintf_bp(bp, "ds=%p", ds);
111
112 ASSERT(dmu_tx_is_syncing(tx));
113 /* It could have been compressed away to nothing */
114 if (BP_IS_HOLE(bp))
115 return;
116 ASSERT(BP_GET_TYPE(bp) != DMU_OT_NONE);
117 ASSERT(DMU_OT_IS_VALID(BP_GET_TYPE(bp)));
118 if (ds == NULL) {
119 dsl_pool_mos_diduse_space(tx->tx_pool,
120 used, compressed, uncompressed);
121 return;
122 }
123
124 dmu_buf_will_dirty(ds->ds_dbuf, tx);
125 mutex_enter(&ds->ds_lock);
126 delta = parent_delta(ds, used);
127 dsl_dataset_phys(ds)->ds_referenced_bytes += used;
128 dsl_dataset_phys(ds)->ds_compressed_bytes += compressed;
129 dsl_dataset_phys(ds)->ds_uncompressed_bytes += uncompressed;
130 dsl_dataset_phys(ds)->ds_unique_bytes += used;
131
132 if (BP_GET_LSIZE(bp) > SPA_OLD_MAXBLOCKSIZE) {
133 ds->ds_feature_activation_needed[SPA_FEATURE_LARGE_BLOCKS] =
134 B_TRUE;
135 }
136
137 spa_feature_t f = zio_checksum_to_feature(BP_GET_CHECKSUM(bp));
138 if (f != SPA_FEATURE_NONE)
139 ds->ds_feature_activation_needed[f] = B_TRUE;
140
141 mutex_exit(&ds->ds_lock);
142 dsl_dir_diduse_space(ds->ds_dir, DD_USED_HEAD, delta,
143 compressed, uncompressed, tx);
144 dsl_dir_transfer_space(ds->ds_dir, used - delta,
145 DD_USED_REFRSRV, DD_USED_HEAD, tx);
146 }
147
148 int
149 dsl_dataset_block_kill(dsl_dataset_t *ds, const blkptr_t *bp, dmu_tx_t *tx,
150 boolean_t async)
151 {
152 int used = bp_get_dsize_sync(tx->tx_pool->dp_spa, bp);
153 int compressed = BP_GET_PSIZE(bp);
154 int uncompressed = BP_GET_UCSIZE(bp);
155
156 if (BP_IS_HOLE(bp))
157 return (0);
158
159 ASSERT(dmu_tx_is_syncing(tx));
160 ASSERT(bp->blk_birth <= tx->tx_txg);
161
162 if (ds == NULL) {
163 dsl_free(tx->tx_pool, tx->tx_txg, bp);
164 dsl_pool_mos_diduse_space(tx->tx_pool,
165 -used, -compressed, -uncompressed);
166 return (used);
167 }
168 ASSERT3P(tx->tx_pool, ==, ds->ds_dir->dd_pool);
169
170 ASSERT(!ds->ds_is_snapshot);
171 dmu_buf_will_dirty(ds->ds_dbuf, tx);
172
173 if (bp->blk_birth > dsl_dataset_phys(ds)->ds_prev_snap_txg) {
174 int64_t delta;
175
176 dprintf_bp(bp, "freeing ds=%llu", ds->ds_object);
177 dsl_free(tx->tx_pool, tx->tx_txg, bp);
178
179 mutex_enter(&ds->ds_lock);
180 ASSERT(dsl_dataset_phys(ds)->ds_unique_bytes >= used ||
181 !DS_UNIQUE_IS_ACCURATE(ds));
182 delta = parent_delta(ds, -used);
183 dsl_dataset_phys(ds)->ds_unique_bytes -= used;
184 mutex_exit(&ds->ds_lock);
185 dsl_dir_diduse_space(ds->ds_dir, DD_USED_HEAD,
186 delta, -compressed, -uncompressed, tx);
187 dsl_dir_transfer_space(ds->ds_dir, -used - delta,
188 DD_USED_REFRSRV, DD_USED_HEAD, tx);
189 } else {
190 dprintf_bp(bp, "putting on dead list: %s", "");
191 if (async) {
192 /*
193 * We are here as part of zio's write done callback,
194 * which means we're a zio interrupt thread. We can't
195 * call dsl_deadlist_insert() now because it may block
196 * waiting for I/O. Instead, put bp on the deferred
197 * queue and let dsl_pool_sync() finish the job.
198 */
199 bplist_append(&ds->ds_pending_deadlist, bp);
200 } else {
201 dsl_deadlist_insert(&ds->ds_deadlist, bp, tx);
202 }
203 ASSERT3U(ds->ds_prev->ds_object, ==,
204 dsl_dataset_phys(ds)->ds_prev_snap_obj);
205 ASSERT(dsl_dataset_phys(ds->ds_prev)->ds_num_children > 0);
206 /* if (bp->blk_birth > prev prev snap txg) prev unique += bs */
207 if (dsl_dataset_phys(ds->ds_prev)->ds_next_snap_obj ==
208 ds->ds_object && bp->blk_birth >
209 dsl_dataset_phys(ds->ds_prev)->ds_prev_snap_txg) {
210 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx);
211 mutex_enter(&ds->ds_prev->ds_lock);
212 dsl_dataset_phys(ds->ds_prev)->ds_unique_bytes += used;
213 mutex_exit(&ds->ds_prev->ds_lock);
214 }
215 if (bp->blk_birth > ds->ds_dir->dd_origin_txg) {
216 dsl_dir_transfer_space(ds->ds_dir, used,
217 DD_USED_HEAD, DD_USED_SNAP, tx);
218 }
219 }
220 mutex_enter(&ds->ds_lock);
221 ASSERT3U(dsl_dataset_phys(ds)->ds_referenced_bytes, >=, used);
222 dsl_dataset_phys(ds)->ds_referenced_bytes -= used;
223 ASSERT3U(dsl_dataset_phys(ds)->ds_compressed_bytes, >=, compressed);
224 dsl_dataset_phys(ds)->ds_compressed_bytes -= compressed;
225 ASSERT3U(dsl_dataset_phys(ds)->ds_uncompressed_bytes, >=, uncompressed);
226 dsl_dataset_phys(ds)->ds_uncompressed_bytes -= uncompressed;
227 mutex_exit(&ds->ds_lock);
228
229 return (used);
230 }
231
232 uint64_t
233 dsl_dataset_prev_snap_txg(dsl_dataset_t *ds)
234 {
235 uint64_t trysnap = 0;
236
237 if (ds == NULL)
238 return (0);
239 /*
240 * The snapshot creation could fail, but that would cause an
241 * incorrect FALSE return, which would only result in an
242 * overestimation of the amount of space that an operation would
243 * consume, which is OK.
244 *
245 * There's also a small window where we could miss a pending
246 * snapshot, because we could set the sync task in the quiescing
247 * phase. So this should only be used as a guess.
248 */
249 if (ds->ds_trysnap_txg >
250 spa_last_synced_txg(ds->ds_dir->dd_pool->dp_spa))
251 trysnap = ds->ds_trysnap_txg;
252 return (MAX(dsl_dataset_phys(ds)->ds_prev_snap_txg, trysnap));
253 }
254
255 boolean_t
256 dsl_dataset_block_freeable(dsl_dataset_t *ds, const blkptr_t *bp,
257 uint64_t blk_birth)
258 {
259 if (blk_birth <= dsl_dataset_prev_snap_txg(ds) ||
260 (bp != NULL && BP_IS_HOLE(bp)))
261 return (B_FALSE);
262
263 ddt_prefetch(dsl_dataset_get_spa(ds), bp);
264
265 return (B_TRUE);
266 }
267
268 static void
269 dsl_dataset_evict(void *dbu)
270 {
271 dsl_dataset_t *ds = dbu;
272
273 ASSERT(ds->ds_owner == NULL);
274
275 ds->ds_dbuf = NULL;
276
277 unique_remove(ds->ds_fsid_guid);
278
279 if (ds->ds_objset != NULL)
280 dmu_objset_evict(ds->ds_objset);
281
282 if (ds->ds_prev) {
283 dsl_dataset_rele(ds->ds_prev, ds);
284 ds->ds_prev = NULL;
285 }
286
287 bplist_destroy(&ds->ds_pending_deadlist);
288 if (ds->ds_deadlist.dl_os != NULL)
289 dsl_deadlist_close(&ds->ds_deadlist);
290 if (ds->ds_dir)
291 dsl_dir_async_rele(ds->ds_dir, ds);
292
293 ASSERT(!list_link_active(&ds->ds_synced_link));
294
295 list_destroy(&ds->ds_prop_cbs);
296 mutex_destroy(&ds->ds_lock);
297 mutex_destroy(&ds->ds_opening_lock);
298 mutex_destroy(&ds->ds_sendstream_lock);
299 refcount_destroy(&ds->ds_longholds);
300
301 kmem_free(ds, sizeof (dsl_dataset_t));
302 }
303
304 int
305 dsl_dataset_get_snapname(dsl_dataset_t *ds)
306 {
307 dsl_dataset_phys_t *headphys;
308 int err;
309 dmu_buf_t *headdbuf;
310 dsl_pool_t *dp = ds->ds_dir->dd_pool;
311 objset_t *mos = dp->dp_meta_objset;
312
313 if (ds->ds_snapname[0])
314 return (0);
315 if (dsl_dataset_phys(ds)->ds_next_snap_obj == 0)
316 return (0);
317
318 err = dmu_bonus_hold(mos, dsl_dir_phys(ds->ds_dir)->dd_head_dataset_obj,
319 FTAG, &headdbuf);
320 if (err != 0)
321 return (err);
322 headphys = headdbuf->db_data;
323 err = zap_value_search(dp->dp_meta_objset,
324 headphys->ds_snapnames_zapobj, ds->ds_object, 0, ds->ds_snapname);
325 dmu_buf_rele(headdbuf, FTAG);
326 return (err);
327 }
328
329 int
330 dsl_dataset_snap_lookup(dsl_dataset_t *ds, const char *name, uint64_t *value)
331 {
332 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
333 uint64_t snapobj = dsl_dataset_phys(ds)->ds_snapnames_zapobj;
334 matchtype_t mt;
335 int err;
336
337 if (dsl_dataset_phys(ds)->ds_flags & DS_FLAG_CI_DATASET)
338 mt = MT_FIRST;
339 else
340 mt = MT_EXACT;
341
342 err = zap_lookup_norm(mos, snapobj, name, 8, 1,
343 value, mt, NULL, 0, NULL);
344 if (err == ENOTSUP && mt == MT_FIRST)
345 err = zap_lookup(mos, snapobj, name, 8, 1, value);
346 return (err);
347 }
348
349 int
350 dsl_dataset_snap_remove(dsl_dataset_t *ds, const char *name, dmu_tx_t *tx,
351 boolean_t adj_cnt)
352 {
353 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
354 uint64_t snapobj = dsl_dataset_phys(ds)->ds_snapnames_zapobj;
355 matchtype_t mt;
356 int err;
357
358 dsl_dir_snap_cmtime_update(ds->ds_dir);
359
360 if (dsl_dataset_phys(ds)->ds_flags & DS_FLAG_CI_DATASET)
361 mt = MT_FIRST;
362 else
363 mt = MT_EXACT;
364
365 err = zap_remove_norm(mos, snapobj, name, mt, tx);
366 if (err == ENOTSUP && mt == MT_FIRST)
367 err = zap_remove(mos, snapobj, name, tx);
368
369 if (err == 0 && adj_cnt)
370 dsl_fs_ss_count_adjust(ds->ds_dir, -1,
371 DD_FIELD_SNAPSHOT_COUNT, tx);
372
373 return (err);
374 }
375
376 boolean_t
377 dsl_dataset_try_add_ref(dsl_pool_t *dp, dsl_dataset_t *ds, void *tag)
378 {
379 dmu_buf_t *dbuf = ds->ds_dbuf;
380 boolean_t result = B_FALSE;
381
382 if (dbuf != NULL && dmu_buf_try_add_ref(dbuf, dp->dp_meta_objset,
383 ds->ds_object, DMU_BONUS_BLKID, tag)) {
384
385 if (ds == dmu_buf_get_user(dbuf))
386 result = B_TRUE;
387 else
388 dmu_buf_rele(dbuf, tag);
389 }
390
391 return (result);
392 }
393
394 int
395 dsl_dataset_hold_obj(dsl_pool_t *dp, uint64_t dsobj, void *tag,
396 dsl_dataset_t **dsp)
397 {
398 objset_t *mos = dp->dp_meta_objset;
399 dmu_buf_t *dbuf;
400 dsl_dataset_t *ds;
401 int err;
402 dmu_object_info_t doi;
403
404 ASSERT(dsl_pool_config_held(dp));
405
406 err = dmu_bonus_hold(mos, dsobj, tag, &dbuf);
407 if (err != 0)
408 return (err);
409
410 /* Make sure dsobj has the correct object type. */
411 dmu_object_info_from_db(dbuf, &doi);
412 if (doi.doi_bonus_type != DMU_OT_DSL_DATASET) {
413 dmu_buf_rele(dbuf, tag);
414 return (SET_ERROR(EINVAL));
415 }
416
417 ds = dmu_buf_get_user(dbuf);
418 if (ds == NULL) {
419 dsl_dataset_t *winner = NULL;
420
421 ds = kmem_zalloc(sizeof (dsl_dataset_t), KM_SLEEP);
422 ds->ds_dbuf = dbuf;
423 ds->ds_object = dsobj;
424 ds->ds_is_snapshot = dsl_dataset_phys(ds)->ds_num_children != 0;
425
426 mutex_init(&ds->ds_lock, NULL, MUTEX_DEFAULT, NULL);
427 mutex_init(&ds->ds_opening_lock, NULL, MUTEX_DEFAULT, NULL);
428 mutex_init(&ds->ds_sendstream_lock, NULL, MUTEX_DEFAULT, NULL);
429 refcount_create(&ds->ds_longholds);
430
431 bplist_create(&ds->ds_pending_deadlist);
432 dsl_deadlist_open(&ds->ds_deadlist,
433 mos, dsl_dataset_phys(ds)->ds_deadlist_obj);
434
435 list_create(&ds->ds_sendstreams, sizeof (dmu_sendarg_t),
436 offsetof(dmu_sendarg_t, dsa_link));
437
438 list_create(&ds->ds_prop_cbs, sizeof (dsl_prop_cb_record_t),
439 offsetof(dsl_prop_cb_record_t, cbr_ds_node));
440
441 if (doi.doi_type == DMU_OTN_ZAP_METADATA) {
442 for (spa_feature_t f = 0; f < SPA_FEATURES; f++) {
443 if (!(spa_feature_table[f].fi_flags &
444 ZFEATURE_FLAG_PER_DATASET))
445 continue;
446 err = zap_contains(mos, dsobj,
447 spa_feature_table[f].fi_guid);
448 if (err == 0) {
449 ds->ds_feature_inuse[f] = B_TRUE;
450 } else {
451 ASSERT3U(err, ==, ENOENT);
452 err = 0;
453 }
454 }
455 }
456
457 err = dsl_dir_hold_obj(dp,
458 dsl_dataset_phys(ds)->ds_dir_obj, NULL, ds, &ds->ds_dir);
459 if (err != 0) {
460 mutex_destroy(&ds->ds_lock);
461 mutex_destroy(&ds->ds_opening_lock);
462 mutex_destroy(&ds->ds_sendstream_lock);
463 refcount_destroy(&ds->ds_longholds);
464 bplist_destroy(&ds->ds_pending_deadlist);
465 dsl_deadlist_close(&ds->ds_deadlist);
466 kmem_free(ds, sizeof (dsl_dataset_t));
467 dmu_buf_rele(dbuf, tag);
468 return (err);
469 }
470
471 if (!ds->ds_is_snapshot) {
472 ds->ds_snapname[0] = '\0';
473 if (dsl_dataset_phys(ds)->ds_prev_snap_obj != 0) {
474 err = dsl_dataset_hold_obj(dp,
475 dsl_dataset_phys(ds)->ds_prev_snap_obj,
476 ds, &ds->ds_prev);
477 }
478 if (doi.doi_type == DMU_OTN_ZAP_METADATA) {
479 int zaperr = zap_lookup(mos, ds->ds_object,
480 DS_FIELD_BOOKMARK_NAMES,
481 sizeof (ds->ds_bookmarks), 1,
482 &ds->ds_bookmarks);
483 if (zaperr != ENOENT)
484 VERIFY0(zaperr);
485 }
486 } else {
487 if (zfs_flags & ZFS_DEBUG_SNAPNAMES)
488 err = dsl_dataset_get_snapname(ds);
489 if (err == 0 &&
490 dsl_dataset_phys(ds)->ds_userrefs_obj != 0) {
491 err = zap_count(
492 ds->ds_dir->dd_pool->dp_meta_objset,
493 dsl_dataset_phys(ds)->ds_userrefs_obj,
494 &ds->ds_userrefs);
495 }
496 }
497
498 if (err == 0 && !ds->ds_is_snapshot) {
499 err = dsl_prop_get_int_ds(ds,
500 zfs_prop_to_name(ZFS_PROP_REFRESERVATION),
501 &ds->ds_reserved);
502 if (err == 0) {
503 err = dsl_prop_get_int_ds(ds,
504 zfs_prop_to_name(ZFS_PROP_REFQUOTA),
505 &ds->ds_quota);
506 }
507 } else {
508 ds->ds_reserved = ds->ds_quota = 0;
509 }
510
511 dmu_buf_init_user(&ds->ds_dbu, dsl_dataset_evict, &ds->ds_dbuf);
512 if (err == 0)
513 winner = dmu_buf_set_user_ie(dbuf, &ds->ds_dbu);
514
515 if (err != 0 || winner != NULL) {
516 bplist_destroy(&ds->ds_pending_deadlist);
517 dsl_deadlist_close(&ds->ds_deadlist);
518 if (ds->ds_prev)
519 dsl_dataset_rele(ds->ds_prev, ds);
520 dsl_dir_rele(ds->ds_dir, ds);
521 mutex_destroy(&ds->ds_lock);
522 mutex_destroy(&ds->ds_opening_lock);
523 mutex_destroy(&ds->ds_sendstream_lock);
524 refcount_destroy(&ds->ds_longholds);
525 kmem_free(ds, sizeof (dsl_dataset_t));
526 if (err != 0) {
527 dmu_buf_rele(dbuf, tag);
528 return (err);
529 }
530 ds = winner;
531 } else {
532 ds->ds_fsid_guid =
533 unique_insert(dsl_dataset_phys(ds)->ds_fsid_guid);
534 }
535 }
536 ASSERT3P(ds->ds_dbuf, ==, dbuf);
537 ASSERT3P(dsl_dataset_phys(ds), ==, dbuf->db_data);
538 ASSERT(dsl_dataset_phys(ds)->ds_prev_snap_obj != 0 ||
539 spa_version(dp->dp_spa) < SPA_VERSION_ORIGIN ||
540 dp->dp_origin_snap == NULL || ds == dp->dp_origin_snap);
541 *dsp = ds;
542 return (0);
543 }
544
545 int
546 dsl_dataset_hold(dsl_pool_t *dp, const char *name,
547 void *tag, dsl_dataset_t **dsp)
548 {
549 dsl_dir_t *dd;
550 const char *snapname;
551 uint64_t obj;
552 int err = 0;
553 dsl_dataset_t *ds;
554
555 err = dsl_dir_hold(dp, name, FTAG, &dd, &snapname);
556 if (err != 0)
557 return (err);
558
559 ASSERT(dsl_pool_config_held(dp));
560 obj = dsl_dir_phys(dd)->dd_head_dataset_obj;
561 if (obj != 0)
562 err = dsl_dataset_hold_obj(dp, obj, tag, &ds);
563 else
564 err = SET_ERROR(ENOENT);
565
566 /* we may be looking for a snapshot */
567 if (err == 0 && snapname != NULL) {
568 dsl_dataset_t *snap_ds;
569
570 if (*snapname++ != '@') {
571 dsl_dataset_rele(ds, tag);
572 dsl_dir_rele(dd, FTAG);
573 return (SET_ERROR(ENOENT));
574 }
575
576 dprintf("looking for snapshot '%s'\n", snapname);
577 err = dsl_dataset_snap_lookup(ds, snapname, &obj);
578 if (err == 0)
579 err = dsl_dataset_hold_obj(dp, obj, tag, &snap_ds);
580 dsl_dataset_rele(ds, tag);
581
582 if (err == 0) {
583 mutex_enter(&snap_ds->ds_lock);
584 if (snap_ds->ds_snapname[0] == 0)
585 (void) strlcpy(snap_ds->ds_snapname, snapname,
586 sizeof (snap_ds->ds_snapname));
587 mutex_exit(&snap_ds->ds_lock);
588 ds = snap_ds;
589 }
590 }
591 if (err == 0)
592 *dsp = ds;
593 dsl_dir_rele(dd, FTAG);
594 return (err);
595 }
596
597 int
598 dsl_dataset_own_obj(dsl_pool_t *dp, uint64_t dsobj,
599 void *tag, dsl_dataset_t **dsp)
600 {
601 int err = dsl_dataset_hold_obj(dp, dsobj, tag, dsp);
602 if (err != 0)
603 return (err);
604 if (!dsl_dataset_tryown(*dsp, tag)) {
605 dsl_dataset_rele(*dsp, tag);
606 *dsp = NULL;
607 return (SET_ERROR(EBUSY));
608 }
609 return (0);
610 }
611
612 int
613 dsl_dataset_own(dsl_pool_t *dp, const char *name,
614 void *tag, dsl_dataset_t **dsp)
615 {
616 int err = dsl_dataset_hold(dp, name, tag, dsp);
617 if (err != 0)
618 return (err);
619 if (!dsl_dataset_tryown(*dsp, tag)) {
620 dsl_dataset_rele(*dsp, tag);
621 return (SET_ERROR(EBUSY));
622 }
623 return (0);
624 }
625
626 /*
627 * See the comment above dsl_pool_hold() for details. In summary, a long
628 * hold is used to prevent destruction of a dataset while the pool hold
629 * is dropped, allowing other concurrent operations (e.g. spa_sync()).
630 *
631 * The dataset and pool must be held when this function is called. After it
632 * is called, the pool hold may be released while the dataset is still held
633 * and accessed.
634 */
635 void
636 dsl_dataset_long_hold(dsl_dataset_t *ds, void *tag)
637 {
638 ASSERT(dsl_pool_config_held(ds->ds_dir->dd_pool));
639 (void) refcount_add(&ds->ds_longholds, tag);
640 }
641
642 void
643 dsl_dataset_long_rele(dsl_dataset_t *ds, void *tag)
644 {
645 (void) refcount_remove(&ds->ds_longholds, tag);
646 }
647
648 /* Return B_TRUE if there are any long holds on this dataset. */
649 boolean_t
650 dsl_dataset_long_held(dsl_dataset_t *ds)
651 {
652 return (!refcount_is_zero(&ds->ds_longholds));
653 }
654
655 void
656 dsl_dataset_name(dsl_dataset_t *ds, char *name)
657 {
658 if (ds == NULL) {
659 (void) strcpy(name, "mos");
660 } else {
661 dsl_dir_name(ds->ds_dir, name);
662 VERIFY0(dsl_dataset_get_snapname(ds));
663 if (ds->ds_snapname[0]) {
664 (void) strcat(name, "@");
665 /*
666 * We use a "recursive" mutex so that we
667 * can call dprintf_ds() with ds_lock held.
668 */
669 if (!MUTEX_HELD(&ds->ds_lock)) {
670 mutex_enter(&ds->ds_lock);
671 (void) strcat(name, ds->ds_snapname);
672 mutex_exit(&ds->ds_lock);
673 } else {
674 (void) strcat(name, ds->ds_snapname);
675 }
676 }
677 }
678 }
679
680 void
681 dsl_dataset_rele(dsl_dataset_t *ds, void *tag)
682 {
683 dmu_buf_rele(ds->ds_dbuf, tag);
684 }
685
686 void
687 dsl_dataset_disown(dsl_dataset_t *ds, void *tag)
688 {
689 ASSERT3P(ds->ds_owner, ==, tag);
690 ASSERT(ds->ds_dbuf != NULL);
691
692 mutex_enter(&ds->ds_lock);
693 ds->ds_owner = NULL;
694 mutex_exit(&ds->ds_lock);
695 dsl_dataset_long_rele(ds, tag);
696 dsl_dataset_rele(ds, tag);
697 }
698
699 boolean_t
700 dsl_dataset_tryown(dsl_dataset_t *ds, void *tag)
701 {
702 boolean_t gotit = FALSE;
703
704 ASSERT(dsl_pool_config_held(ds->ds_dir->dd_pool));
705 mutex_enter(&ds->ds_lock);
706 if (ds->ds_owner == NULL && !DS_IS_INCONSISTENT(ds)) {
707 ds->ds_owner = tag;
708 dsl_dataset_long_hold(ds, tag);
709 gotit = TRUE;
710 }
711 mutex_exit(&ds->ds_lock);
712 return (gotit);
713 }
714
715 boolean_t
716 dsl_dataset_has_owner(dsl_dataset_t *ds)
717 {
718 boolean_t rv;
719 mutex_enter(&ds->ds_lock);
720 rv = (ds->ds_owner != NULL);
721 mutex_exit(&ds->ds_lock);
722 return (rv);
723 }
724
725 static void
726 dsl_dataset_activate_feature(uint64_t dsobj, spa_feature_t f, dmu_tx_t *tx)
727 {
728 spa_t *spa = dmu_tx_pool(tx)->dp_spa;
729 objset_t *mos = dmu_tx_pool(tx)->dp_meta_objset;
730 uint64_t zero = 0;
731
732 VERIFY(spa_feature_table[f].fi_flags & ZFEATURE_FLAG_PER_DATASET);
733
734 spa_feature_incr(spa, f, tx);
735 dmu_object_zapify(mos, dsobj, DMU_OT_DSL_DATASET, tx);
736
737 VERIFY0(zap_add(mos, dsobj, spa_feature_table[f].fi_guid,
738 sizeof (zero), 1, &zero, tx));
739 }
740
741 void
742 dsl_dataset_deactivate_feature(uint64_t dsobj, spa_feature_t f, dmu_tx_t *tx)
743 {
744 spa_t *spa = dmu_tx_pool(tx)->dp_spa;
745 objset_t *mos = dmu_tx_pool(tx)->dp_meta_objset;
746
747 VERIFY(spa_feature_table[f].fi_flags & ZFEATURE_FLAG_PER_DATASET);
748
749 VERIFY0(zap_remove(mos, dsobj, spa_feature_table[f].fi_guid, tx));
750 spa_feature_decr(spa, f, tx);
751 }
752
753 uint64_t
754 dsl_dataset_create_sync_dd(dsl_dir_t *dd, dsl_dataset_t *origin,
755 uint64_t flags, dmu_tx_t *tx)
756 {
757 dsl_pool_t *dp = dd->dd_pool;
758 dmu_buf_t *dbuf;
759 dsl_dataset_phys_t *dsphys;
760 uint64_t dsobj;
761 objset_t *mos = dp->dp_meta_objset;
762
763 if (origin == NULL)
764 origin = dp->dp_origin_snap;
765
766 ASSERT(origin == NULL || origin->ds_dir->dd_pool == dp);
767 ASSERT(origin == NULL || dsl_dataset_phys(origin)->ds_num_children > 0);
768 ASSERT(dmu_tx_is_syncing(tx));
769 ASSERT(dsl_dir_phys(dd)->dd_head_dataset_obj == 0);
770
771 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0,
772 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx);
773 VERIFY0(dmu_bonus_hold(mos, dsobj, FTAG, &dbuf));
774 dmu_buf_will_dirty(dbuf, tx);
775 dsphys = dbuf->db_data;
776 bzero(dsphys, sizeof (dsl_dataset_phys_t));
777 dsphys->ds_dir_obj = dd->dd_object;
778 dsphys->ds_flags = flags;
779 dsphys->ds_fsid_guid = unique_create();
780 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid,
781 sizeof (dsphys->ds_guid));
782 dsphys->ds_snapnames_zapobj =
783 zap_create_norm(mos, U8_TEXTPREP_TOUPPER, DMU_OT_DSL_DS_SNAP_MAP,
784 DMU_OT_NONE, 0, tx);
785 dsphys->ds_creation_time = gethrestime_sec();
786 dsphys->ds_creation_txg = tx->tx_txg == TXG_INITIAL ? 1 : tx->tx_txg;
787
788 if (origin == NULL) {
789 dsphys->ds_deadlist_obj = dsl_deadlist_alloc(mos, tx);
790 } else {
791 dsl_dataset_t *ohds; /* head of the origin snapshot */
792
793 dsphys->ds_prev_snap_obj = origin->ds_object;
794 dsphys->ds_prev_snap_txg =
795 dsl_dataset_phys(origin)->ds_creation_txg;
796 dsphys->ds_referenced_bytes =
797 dsl_dataset_phys(origin)->ds_referenced_bytes;
798 dsphys->ds_compressed_bytes =
799 dsl_dataset_phys(origin)->ds_compressed_bytes;
800 dsphys->ds_uncompressed_bytes =
801 dsl_dataset_phys(origin)->ds_uncompressed_bytes;
802 dsphys->ds_bp = dsl_dataset_phys(origin)->ds_bp;
803
804 /*
805 * Inherit flags that describe the dataset's contents
806 * (INCONSISTENT) or properties (Case Insensitive).
807 */
808 dsphys->ds_flags |= dsl_dataset_phys(origin)->ds_flags &
809 (DS_FLAG_INCONSISTENT | DS_FLAG_CI_DATASET);
810
811 for (spa_feature_t f = 0; f < SPA_FEATURES; f++) {
812 if (origin->ds_feature_inuse[f])
813 dsl_dataset_activate_feature(dsobj, f, tx);
814 }
815
816 dmu_buf_will_dirty(origin->ds_dbuf, tx);
817 dsl_dataset_phys(origin)->ds_num_children++;
818
819 VERIFY0(dsl_dataset_hold_obj(dp,
820 dsl_dir_phys(origin->ds_dir)->dd_head_dataset_obj,
821 FTAG, &ohds));
822 dsphys->ds_deadlist_obj = dsl_deadlist_clone(&ohds->ds_deadlist,
823 dsphys->ds_prev_snap_txg, dsphys->ds_prev_snap_obj, tx);
824 dsl_dataset_rele(ohds, FTAG);
825
826 if (spa_version(dp->dp_spa) >= SPA_VERSION_NEXT_CLONES) {
827 if (dsl_dataset_phys(origin)->ds_next_clones_obj == 0) {
828 dsl_dataset_phys(origin)->ds_next_clones_obj =
829 zap_create(mos,
830 DMU_OT_NEXT_CLONES, DMU_OT_NONE, 0, tx);
831 }
832 VERIFY0(zap_add_int(mos,
833 dsl_dataset_phys(origin)->ds_next_clones_obj,
834 dsobj, tx));
835 }
836
837 dmu_buf_will_dirty(dd->dd_dbuf, tx);
838 dsl_dir_phys(dd)->dd_origin_obj = origin->ds_object;
839 if (spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) {
840 if (dsl_dir_phys(origin->ds_dir)->dd_clones == 0) {
841 dmu_buf_will_dirty(origin->ds_dir->dd_dbuf, tx);
842 dsl_dir_phys(origin->ds_dir)->dd_clones =
843 zap_create(mos,
844 DMU_OT_DSL_CLONES, DMU_OT_NONE, 0, tx);
845 }
846 VERIFY0(zap_add_int(mos,
847 dsl_dir_phys(origin->ds_dir)->dd_clones,
848 dsobj, tx));
849 }
850 }
851
852 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE)
853 dsphys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE;
854
855 dmu_buf_rele(dbuf, FTAG);
856
857 dmu_buf_will_dirty(dd->dd_dbuf, tx);
858 dsl_dir_phys(dd)->dd_head_dataset_obj = dsobj;
859
860 return (dsobj);
861 }
862
863 static void
864 dsl_dataset_zero_zil(dsl_dataset_t *ds, dmu_tx_t *tx)
865 {
866 objset_t *os;
867
868 VERIFY0(dmu_objset_from_ds(ds, &os));
869 bzero(&os->os_zil_header, sizeof (os->os_zil_header));
870 dsl_dataset_dirty(ds, tx);
871 }
872
873 uint64_t
874 dsl_dataset_create_sync(dsl_dir_t *pdd, const char *lastname,
875 dsl_dataset_t *origin, uint64_t flags, cred_t *cr, dmu_tx_t *tx)
876 {
877 dsl_pool_t *dp = pdd->dd_pool;
878 uint64_t dsobj, ddobj;
879 dsl_dir_t *dd;
880
881 ASSERT(dmu_tx_is_syncing(tx));
882 ASSERT(lastname[0] != '@');
883
884 ddobj = dsl_dir_create_sync(dp, pdd, lastname, tx);
885 VERIFY0(dsl_dir_hold_obj(dp, ddobj, lastname, FTAG, &dd));
886
887 dsobj = dsl_dataset_create_sync_dd(dd, origin,
888 flags & ~DS_CREATE_FLAG_NODIRTY, tx);
889
890 dsl_deleg_set_create_perms(dd, tx, cr);
891
892 /*
893 * Since we're creating a new node we know it's a leaf, so we can
894 * initialize the counts if the limit feature is active.
895 */
896 if (spa_feature_is_active(dp->dp_spa, SPA_FEATURE_FS_SS_LIMIT)) {
897 uint64_t cnt = 0;
898 objset_t *os = dd->dd_pool->dp_meta_objset;
899
900 dsl_dir_zapify(dd, tx);
901 VERIFY0(zap_add(os, dd->dd_object, DD_FIELD_FILESYSTEM_COUNT,
902 sizeof (cnt), 1, &cnt, tx));
903 VERIFY0(zap_add(os, dd->dd_object, DD_FIELD_SNAPSHOT_COUNT,
904 sizeof (cnt), 1, &cnt, tx));
905 }
906
907 dsl_dir_rele(dd, FTAG);
908
909 /*
910 * If we are creating a clone, make sure we zero out any stale
911 * data from the origin snapshots zil header.
912 */
913 if (origin != NULL && !(flags & DS_CREATE_FLAG_NODIRTY)) {
914 dsl_dataset_t *ds;
915
916 VERIFY0(dsl_dataset_hold_obj(dp, dsobj, FTAG, &ds));
917 dsl_dataset_zero_zil(ds, tx);
918 dsl_dataset_rele(ds, FTAG);
919 }
920
921 return (dsobj);
922 }
923
924 /*
925 * The unique space in the head dataset can be calculated by subtracting
926 * the space used in the most recent snapshot, that is still being used
927 * in this file system, from the space currently in use. To figure out
928 * the space in the most recent snapshot still in use, we need to take
929 * the total space used in the snapshot and subtract out the space that
930 * has been freed up since the snapshot was taken.
931 */
932 void
933 dsl_dataset_recalc_head_uniq(dsl_dataset_t *ds)
934 {
935 uint64_t mrs_used;
936 uint64_t dlused, dlcomp, dluncomp;
937
938 ASSERT(!ds->ds_is_snapshot);
939
940 if (dsl_dataset_phys(ds)->ds_prev_snap_obj != 0)
941 mrs_used = dsl_dataset_phys(ds->ds_prev)->ds_referenced_bytes;
942 else
943 mrs_used = 0;
944
945 dsl_deadlist_space(&ds->ds_deadlist, &dlused, &dlcomp, &dluncomp);
946
947 ASSERT3U(dlused, <=, mrs_used);
948 dsl_dataset_phys(ds)->ds_unique_bytes =
949 dsl_dataset_phys(ds)->ds_referenced_bytes - (mrs_used - dlused);
950
951 if (spa_version(ds->ds_dir->dd_pool->dp_spa) >=
952 SPA_VERSION_UNIQUE_ACCURATE)
953 dsl_dataset_phys(ds)->ds_flags |= DS_FLAG_UNIQUE_ACCURATE;
954 }
955
956 void
957 dsl_dataset_remove_from_next_clones(dsl_dataset_t *ds, uint64_t obj,
958 dmu_tx_t *tx)
959 {
960 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
961 uint64_t count;
962 int err;
963
964 ASSERT(dsl_dataset_phys(ds)->ds_num_children >= 2);
965 err = zap_remove_int(mos, dsl_dataset_phys(ds)->ds_next_clones_obj,
966 obj, tx);
967 /*
968 * The err should not be ENOENT, but a bug in a previous version
969 * of the code could cause upgrade_clones_cb() to not set
970 * ds_next_snap_obj when it should, leading to a missing entry.
971 * If we knew that the pool was created after
972 * SPA_VERSION_NEXT_CLONES, we could assert that it isn't
973 * ENOENT. However, at least we can check that we don't have
974 * too many entries in the next_clones_obj even after failing to
975 * remove this one.
976 */
977 if (err != ENOENT)
978 VERIFY0(err);
979 ASSERT0(zap_count(mos, dsl_dataset_phys(ds)->ds_next_clones_obj,
980 &count));
981 ASSERT3U(count, <=, dsl_dataset_phys(ds)->ds_num_children - 2);
982 }
983
984
985 blkptr_t *
986 dsl_dataset_get_blkptr(dsl_dataset_t *ds)
987 {
988 return (&dsl_dataset_phys(ds)->ds_bp);
989 }
990
991 void
992 dsl_dataset_set_blkptr(dsl_dataset_t *ds, blkptr_t *bp, dmu_tx_t *tx)
993 {
994 ASSERT(dmu_tx_is_syncing(tx));
995 /* If it's the meta-objset, set dp_meta_rootbp */
996 if (ds == NULL) {
997 tx->tx_pool->dp_meta_rootbp = *bp;
998 } else {
999 dmu_buf_will_dirty(ds->ds_dbuf, tx);
1000 dsl_dataset_phys(ds)->ds_bp = *bp;
1001 }
1002 }
1003
1004 spa_t *
1005 dsl_dataset_get_spa(dsl_dataset_t *ds)
1006 {
1007 return (ds->ds_dir->dd_pool->dp_spa);
1008 }
1009
1010 void
1011 dsl_dataset_dirty(dsl_dataset_t *ds, dmu_tx_t *tx)
1012 {
1013 dsl_pool_t *dp;
1014
1015 if (ds == NULL) /* this is the meta-objset */
1016 return;
1017
1018 ASSERT(ds->ds_objset != NULL);
1019
1020 if (dsl_dataset_phys(ds)->ds_next_snap_obj != 0)
1021 panic("dirtying snapshot!");
1022
1023 dp = ds->ds_dir->dd_pool;
1024
1025 if (txg_list_add(&dp->dp_dirty_datasets, ds, tx->tx_txg)) {
1026 /* up the hold count until we can be written out */
1027 dmu_buf_add_ref(ds->ds_dbuf, ds);
1028 }
1029 }
1030
1031 boolean_t
1032 dsl_dataset_is_dirty(dsl_dataset_t *ds)
1033 {
1034 for (int t = 0; t < TXG_SIZE; t++) {
1035 if (txg_list_member(&ds->ds_dir->dd_pool->dp_dirty_datasets,
1036 ds, t))
1037 return (B_TRUE);
1038 }
1039 return (B_FALSE);
1040 }
1041
1042 static int
1043 dsl_dataset_snapshot_reserve_space(dsl_dataset_t *ds, dmu_tx_t *tx)
1044 {
1045 uint64_t asize;
1046
1047 if (!dmu_tx_is_syncing(tx))
1048 return (0);
1049
1050 /*
1051 * If there's an fs-only reservation, any blocks that might become
1052 * owned by the snapshot dataset must be accommodated by space
1053 * outside of the reservation.
1054 */
1055 ASSERT(ds->ds_reserved == 0 || DS_UNIQUE_IS_ACCURATE(ds));
1056 asize = MIN(dsl_dataset_phys(ds)->ds_unique_bytes, ds->ds_reserved);
1057 if (asize > dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE))
1058 return (SET_ERROR(ENOSPC));
1059
1060 /*
1061 * Propagate any reserved space for this snapshot to other
1062 * snapshot checks in this sync group.
1063 */
1064 if (asize > 0)
1065 dsl_dir_willuse_space(ds->ds_dir, asize, tx);
1066
1067 return (0);
1068 }
1069
1070 typedef struct dsl_dataset_snapshot_arg {
1071 nvlist_t *ddsa_snaps;
1072 nvlist_t *ddsa_props;
1073 nvlist_t *ddsa_errors;
1074 cred_t *ddsa_cr;
1075 } dsl_dataset_snapshot_arg_t;
1076
1077 int
1078 dsl_dataset_snapshot_check_impl(dsl_dataset_t *ds, const char *snapname,
1079 dmu_tx_t *tx, boolean_t recv, uint64_t cnt, cred_t *cr)
1080 {
1081 int error;
1082 uint64_t value;
1083
1084 ds->ds_trysnap_txg = tx->tx_txg;
1085
1086 if (!dmu_tx_is_syncing(tx))
1087 return (0);
1088
1089 /*
1090 * We don't allow multiple snapshots of the same txg. If there
1091 * is already one, try again.
1092 */
1093 if (dsl_dataset_phys(ds)->ds_prev_snap_txg >= tx->tx_txg)
1094 return (SET_ERROR(EAGAIN));
1095
1096 /*
1097 * Check for conflicting snapshot name.
1098 */
1099 error = dsl_dataset_snap_lookup(ds, snapname, &value);
1100 if (error == 0)
1101 return (SET_ERROR(EEXIST));
1102 if (error != ENOENT)
1103 return (error);
1104
1105 /*
1106 * We don't allow taking snapshots of inconsistent datasets, such as
1107 * those into which we are currently receiving. However, if we are
1108 * creating this snapshot as part of a receive, this check will be
1109 * executed atomically with respect to the completion of the receive
1110 * itself but prior to the clearing of DS_FLAG_INCONSISTENT; in this
1111 * case we ignore this, knowing it will be fixed up for us shortly in
1112 * dmu_recv_end_sync().
1113 */
1114 if (!recv && DS_IS_INCONSISTENT(ds))
1115 return (SET_ERROR(EBUSY));
1116
1117 /*
1118 * Skip the check for temporary snapshots or if we have already checked
1119 * the counts in dsl_dataset_snapshot_check. This means we really only
1120 * check the count here when we're receiving a stream.
1121 */
1122 if (cnt != 0 && cr != NULL) {
1123 error = dsl_fs_ss_limit_check(ds->ds_dir, cnt,
1124 ZFS_PROP_SNAPSHOT_LIMIT, NULL, cr);
1125 if (error != 0)
1126 return (error);
1127 }
1128
1129 error = dsl_dataset_snapshot_reserve_space(ds, tx);
1130 if (error != 0)
1131 return (error);
1132
1133 return (0);
1134 }
1135
1136 static int
1137 dsl_dataset_snapshot_check(void *arg, dmu_tx_t *tx)
1138 {
1139 dsl_dataset_snapshot_arg_t *ddsa = arg;
1140 dsl_pool_t *dp = dmu_tx_pool(tx);
1141 nvpair_t *pair;
1142 int rv = 0;
1143
1144 /*
1145 * Pre-compute how many total new snapshots will be created for each
1146 * level in the tree and below. This is needed for validating the
1147 * snapshot limit when either taking a recursive snapshot or when
1148 * taking multiple snapshots.
1149 *
1150 * The problem is that the counts are not actually adjusted when
1151 * we are checking, only when we finally sync. For a single snapshot,
1152 * this is easy, the count will increase by 1 at each node up the tree,
1153 * but its more complicated for the recursive/multiple snapshot case.
1154 *
1155 * The dsl_fs_ss_limit_check function does recursively check the count
1156 * at each level up the tree but since it is validating each snapshot
1157 * independently we need to be sure that we are validating the complete
1158 * count for the entire set of snapshots. We do this by rolling up the
1159 * counts for each component of the name into an nvlist and then
1160 * checking each of those cases with the aggregated count.
1161 *
1162 * This approach properly handles not only the recursive snapshot
1163 * case (where we get all of those on the ddsa_snaps list) but also
1164 * the sibling case (e.g. snapshot a/b and a/c so that we will also
1165 * validate the limit on 'a' using a count of 2).
1166 *
1167 * We validate the snapshot names in the third loop and only report
1168 * name errors once.
1169 */
1170 if (dmu_tx_is_syncing(tx)) {
1171 nvlist_t *cnt_track = NULL;
1172 cnt_track = fnvlist_alloc();
1173
1174 /* Rollup aggregated counts into the cnt_track list */
1175 for (pair = nvlist_next_nvpair(ddsa->ddsa_snaps, NULL);
1176 pair != NULL;
1177 pair = nvlist_next_nvpair(ddsa->ddsa_snaps, pair)) {
1178 char *pdelim;
1179 uint64_t val;
1180 char nm[MAXPATHLEN];
1181
1182 (void) strlcpy(nm, nvpair_name(pair), sizeof (nm));
1183 pdelim = strchr(nm, '@');
1184 if (pdelim == NULL)
1185 continue;
1186 *pdelim = '\0';
1187
1188 do {
1189 if (nvlist_lookup_uint64(cnt_track, nm,
1190 &val) == 0) {
1191 /* update existing entry */
1192 fnvlist_add_uint64(cnt_track, nm,
1193 val + 1);
1194 } else {
1195 /* add to list */
1196 fnvlist_add_uint64(cnt_track, nm, 1);
1197 }
1198
1199 pdelim = strrchr(nm, '/');
1200 if (pdelim != NULL)
1201 *pdelim = '\0';
1202 } while (pdelim != NULL);
1203 }
1204
1205 /* Check aggregated counts at each level */
1206 for (pair = nvlist_next_nvpair(cnt_track, NULL);
1207 pair != NULL; pair = nvlist_next_nvpair(cnt_track, pair)) {
1208 int error = 0;
1209 char *name;
1210 uint64_t cnt = 0;
1211 dsl_dataset_t *ds;
1212
1213 name = nvpair_name(pair);
1214 cnt = fnvpair_value_uint64(pair);
1215 ASSERT(cnt > 0);
1216
1217 error = dsl_dataset_hold(dp, name, FTAG, &ds);
1218 if (error == 0) {
1219 error = dsl_fs_ss_limit_check(ds->ds_dir, cnt,
1220 ZFS_PROP_SNAPSHOT_LIMIT, NULL,
1221 ddsa->ddsa_cr);
1222 dsl_dataset_rele(ds, FTAG);
1223 }
1224
1225 if (error != 0) {
1226 if (ddsa->ddsa_errors != NULL)
1227 fnvlist_add_int32(ddsa->ddsa_errors,
1228 name, error);
1229 rv = error;
1230 /* only report one error for this check */
1231 break;
1232 }
1233 }
1234 nvlist_free(cnt_track);
1235 }
1236
1237 for (pair = nvlist_next_nvpair(ddsa->ddsa_snaps, NULL);
1238 pair != NULL; pair = nvlist_next_nvpair(ddsa->ddsa_snaps, pair)) {
1239 int error = 0;
1240 dsl_dataset_t *ds;
1241 char *name, *atp;
1242 char dsname[MAXNAMELEN];
1243
1244 name = nvpair_name(pair);
1245 if (strlen(name) >= MAXNAMELEN)
1246 error = SET_ERROR(ENAMETOOLONG);
1247 if (error == 0) {
1248 atp = strchr(name, '@');
1249 if (atp == NULL)
1250 error = SET_ERROR(EINVAL);
1251 if (error == 0)
1252 (void) strlcpy(dsname, name, atp - name + 1);
1253 }
1254 if (error == 0)
1255 error = dsl_dataset_hold(dp, dsname, FTAG, &ds);
1256 if (error == 0) {
1257 /* passing 0/NULL skips dsl_fs_ss_limit_check */
1258 error = dsl_dataset_snapshot_check_impl(ds,
1259 atp + 1, tx, B_FALSE, 0, NULL);
1260 dsl_dataset_rele(ds, FTAG);
1261 }
1262
1263 if (error != 0) {
1264 if (ddsa->ddsa_errors != NULL) {
1265 fnvlist_add_int32(ddsa->ddsa_errors,
1266 name, error);
1267 }
1268 rv = error;
1269 }
1270 }
1271
1272 return (rv);
1273 }
1274
1275 void
1276 dsl_dataset_snapshot_sync_impl(dsl_dataset_t *ds, const char *snapname,
1277 dmu_tx_t *tx)
1278 {
1279 static zil_header_t zero_zil;
1280
1281 dsl_pool_t *dp = ds->ds_dir->dd_pool;
1282 dmu_buf_t *dbuf;
1283 dsl_dataset_phys_t *dsphys;
1284 uint64_t dsobj, crtxg;
1285 objset_t *mos = dp->dp_meta_objset;
1286 objset_t *os;
1287
1288 ASSERT(RRW_WRITE_HELD(&dp->dp_config_rwlock));
1289
1290 /*
1291 * If we are on an old pool, the zil must not be active, in which
1292 * case it will be zeroed. Usually zil_suspend() accomplishes this.
1293 */
1294 ASSERT(spa_version(dmu_tx_pool(tx)->dp_spa) >= SPA_VERSION_FAST_SNAP ||
1295 dmu_objset_from_ds(ds, &os) != 0 ||
1296 bcmp(&os->os_phys->os_zil_header, &zero_zil,
1297 sizeof (zero_zil)) == 0);
1298
1299 dsl_fs_ss_count_adjust(ds->ds_dir, 1, DD_FIELD_SNAPSHOT_COUNT, tx);
1300
1301 /*
1302 * The origin's ds_creation_txg has to be < TXG_INITIAL
1303 */
1304 if (strcmp(snapname, ORIGIN_DIR_NAME) == 0)
1305 crtxg = 1;
1306 else
1307 crtxg = tx->tx_txg;
1308
1309 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0,
1310 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx);
1311 VERIFY0(dmu_bonus_hold(mos, dsobj, FTAG, &dbuf));
1312 dmu_buf_will_dirty(dbuf, tx);
1313 dsphys = dbuf->db_data;
1314 bzero(dsphys, sizeof (dsl_dataset_phys_t));
1315 dsphys->ds_dir_obj = ds->ds_dir->dd_object;
1316 dsphys->ds_fsid_guid = unique_create();
1317 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid,
1318 sizeof (dsphys->ds_guid));
1319 dsphys->ds_prev_snap_obj = dsl_dataset_phys(ds)->ds_prev_snap_obj;
1320 dsphys->ds_prev_snap_txg = dsl_dataset_phys(ds)->ds_prev_snap_txg;
1321 dsphys->ds_next_snap_obj = ds->ds_object;
1322 dsphys->ds_num_children = 1;
1323 dsphys->ds_creation_time = gethrestime_sec();
1324 dsphys->ds_creation_txg = crtxg;
1325 dsphys->ds_deadlist_obj = dsl_dataset_phys(ds)->ds_deadlist_obj;
1326 dsphys->ds_referenced_bytes = dsl_dataset_phys(ds)->ds_referenced_bytes;
1327 dsphys->ds_compressed_bytes = dsl_dataset_phys(ds)->ds_compressed_bytes;
1328 dsphys->ds_uncompressed_bytes =
1329 dsl_dataset_phys(ds)->ds_uncompressed_bytes;
1330 dsphys->ds_flags = dsl_dataset_phys(ds)->ds_flags;
1331 dsphys->ds_bp = dsl_dataset_phys(ds)->ds_bp;
1332 dmu_buf_rele(dbuf, FTAG);
1333
1334 for (spa_feature_t f = 0; f < SPA_FEATURES; f++) {
1335 if (ds->ds_feature_inuse[f])
1336 dsl_dataset_activate_feature(dsobj, f, tx);
1337 }
1338
1339 ASSERT3U(ds->ds_prev != 0, ==,
1340 dsl_dataset_phys(ds)->ds_prev_snap_obj != 0);
1341 if (ds->ds_prev) {
1342 uint64_t next_clones_obj =
1343 dsl_dataset_phys(ds->ds_prev)->ds_next_clones_obj;
1344 ASSERT(dsl_dataset_phys(ds->ds_prev)->ds_next_snap_obj ==
1345 ds->ds_object ||
1346 dsl_dataset_phys(ds->ds_prev)->ds_num_children > 1);
1347 if (dsl_dataset_phys(ds->ds_prev)->ds_next_snap_obj ==
1348 ds->ds_object) {
1349 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx);
1350 ASSERT3U(dsl_dataset_phys(ds)->ds_prev_snap_txg, ==,
1351 dsl_dataset_phys(ds->ds_prev)->ds_creation_txg);
1352 dsl_dataset_phys(ds->ds_prev)->ds_next_snap_obj = dsobj;
1353 } else if (next_clones_obj != 0) {
1354 dsl_dataset_remove_from_next_clones(ds->ds_prev,
1355 dsphys->ds_next_snap_obj, tx);
1356 VERIFY0(zap_add_int(mos,
1357 next_clones_obj, dsobj, tx));
1358 }
1359 }
1360
1361 /*
1362 * If we have a reference-reservation on this dataset, we will
1363 * need to increase the amount of refreservation being charged
1364 * since our unique space is going to zero.
1365 */
1366 if (ds->ds_reserved) {
1367 int64_t delta;
1368 ASSERT(DS_UNIQUE_IS_ACCURATE(ds));
1369 delta = MIN(dsl_dataset_phys(ds)->ds_unique_bytes,
1370 ds->ds_reserved);
1371 dsl_dir_diduse_space(ds->ds_dir, DD_USED_REFRSRV,
1372 delta, 0, 0, tx);
1373 }
1374
1375 dmu_buf_will_dirty(ds->ds_dbuf, tx);
1376 dsl_dataset_phys(ds)->ds_deadlist_obj =
1377 dsl_deadlist_clone(&ds->ds_deadlist, UINT64_MAX,
1378 dsl_dataset_phys(ds)->ds_prev_snap_obj, tx);
1379 dsl_deadlist_close(&ds->ds_deadlist);
1380 dsl_deadlist_open(&ds->ds_deadlist, mos,
1381 dsl_dataset_phys(ds)->ds_deadlist_obj);
1382 dsl_deadlist_add_key(&ds->ds_deadlist,
1383 dsl_dataset_phys(ds)->ds_prev_snap_txg, tx);
1384
1385 ASSERT3U(dsl_dataset_phys(ds)->ds_prev_snap_txg, <, tx->tx_txg);
1386 dsl_dataset_phys(ds)->ds_prev_snap_obj = dsobj;
1387 dsl_dataset_phys(ds)->ds_prev_snap_txg = crtxg;
1388 dsl_dataset_phys(ds)->ds_unique_bytes = 0;
1389 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE)
1390 dsl_dataset_phys(ds)->ds_flags |= DS_FLAG_UNIQUE_ACCURATE;
1391
1392 VERIFY0(zap_add(mos, dsl_dataset_phys(ds)->ds_snapnames_zapobj,
1393 snapname, 8, 1, &dsobj, tx));
1394
1395 if (ds->ds_prev)
1396 dsl_dataset_rele(ds->ds_prev, ds);
1397 VERIFY0(dsl_dataset_hold_obj(dp,
1398 dsl_dataset_phys(ds)->ds_prev_snap_obj, ds, &ds->ds_prev));
1399
1400 dsl_scan_ds_snapshotted(ds, tx);
1401
1402 dsl_dir_snap_cmtime_update(ds->ds_dir);
1403
1404 spa_history_log_internal_ds(ds->ds_prev, "snapshot", tx, "");
1405 }
1406
1407 static void
1408 dsl_dataset_snapshot_sync(void *arg, dmu_tx_t *tx)
1409 {
1410 dsl_dataset_snapshot_arg_t *ddsa = arg;
1411 dsl_pool_t *dp = dmu_tx_pool(tx);
1412 nvpair_t *pair;
1413
1414 for (pair = nvlist_next_nvpair(ddsa->ddsa_snaps, NULL);
1415 pair != NULL; pair = nvlist_next_nvpair(ddsa->ddsa_snaps, pair)) {
1416 dsl_dataset_t *ds;
1417 char *name, *atp;
1418 char dsname[MAXNAMELEN];
1419
1420 name = nvpair_name(pair);
1421 atp = strchr(name, '@');
1422 (void) strlcpy(dsname, name, atp - name + 1);
1423 VERIFY0(dsl_dataset_hold(dp, dsname, FTAG, &ds));
1424
1425 dsl_dataset_snapshot_sync_impl(ds, atp + 1, tx);
1426 if (ddsa->ddsa_props != NULL) {
1427 dsl_props_set_sync_impl(ds->ds_prev,
1428 ZPROP_SRC_LOCAL, ddsa->ddsa_props, tx);
1429 }
1430 dsl_dataset_rele(ds, FTAG);
1431 }
1432 }
1433
1434 /*
1435 * The snapshots must all be in the same pool.
1436 * All-or-nothing: if there are any failures, nothing will be modified.
1437 */
1438 int
1439 dsl_dataset_snapshot(nvlist_t *snaps, nvlist_t *props, nvlist_t *errors)
1440 {
1441 dsl_dataset_snapshot_arg_t ddsa;
1442 nvpair_t *pair;
1443 boolean_t needsuspend;
1444 int error;
1445 spa_t *spa;
1446 char *firstname;
1447 nvlist_t *suspended = NULL;
1448
1449 pair = nvlist_next_nvpair(snaps, NULL);
1450 if (pair == NULL)
1451 return (0);
1452 firstname = nvpair_name(pair);
1453
1454 error = spa_open(firstname, &spa, FTAG);
1455 if (error != 0)
1456 return (error);
1457 needsuspend = (spa_version(spa) < SPA_VERSION_FAST_SNAP);
1458 spa_close(spa, FTAG);
1459
1460 if (needsuspend) {
1461 suspended = fnvlist_alloc();
1462 for (pair = nvlist_next_nvpair(snaps, NULL); pair != NULL;
1463 pair = nvlist_next_nvpair(snaps, pair)) {
1464 char fsname[MAXNAMELEN];
1465 char *snapname = nvpair_name(pair);
1466 char *atp;
1467 void *cookie;
1468
1469 atp = strchr(snapname, '@');
1470 if (atp == NULL) {
1471 error = SET_ERROR(EINVAL);
1472 break;
1473 }
1474 (void) strlcpy(fsname, snapname, atp - snapname + 1);
1475
1476 error = zil_suspend(fsname, &cookie);
1477 if (error != 0)
1478 break;
1479 fnvlist_add_uint64(suspended, fsname,
1480 (uintptr_t)cookie);
1481 }
1482 }
1483
1484 ddsa.ddsa_snaps = snaps;
1485 ddsa.ddsa_props = props;
1486 ddsa.ddsa_errors = errors;
1487 ddsa.ddsa_cr = CRED();
1488
1489 if (error == 0) {
1490 error = dsl_sync_task(firstname, dsl_dataset_snapshot_check,
1491 dsl_dataset_snapshot_sync, &ddsa,
1492 fnvlist_num_pairs(snaps) * 3, ZFS_SPACE_CHECK_NORMAL);
1493 }
1494
1495 if (suspended != NULL) {
1496 for (pair = nvlist_next_nvpair(suspended, NULL); pair != NULL;
1497 pair = nvlist_next_nvpair(suspended, pair)) {
1498 zil_resume((void *)(uintptr_t)
1499 fnvpair_value_uint64(pair));
1500 }
1501 fnvlist_free(suspended);
1502 }
1503
1504 return (error);
1505 }
1506
1507 typedef struct dsl_dataset_snapshot_tmp_arg {
1508 const char *ddsta_fsname;
1509 const char *ddsta_snapname;
1510 minor_t ddsta_cleanup_minor;
1511 const char *ddsta_htag;
1512 } dsl_dataset_snapshot_tmp_arg_t;
1513
1514 static int
1515 dsl_dataset_snapshot_tmp_check(void *arg, dmu_tx_t *tx)
1516 {
1517 dsl_dataset_snapshot_tmp_arg_t *ddsta = arg;
1518 dsl_pool_t *dp = dmu_tx_pool(tx);
1519 dsl_dataset_t *ds;
1520 int error;
1521
1522 error = dsl_dataset_hold(dp, ddsta->ddsta_fsname, FTAG, &ds);
1523 if (error != 0)
1524 return (error);
1525
1526 /* NULL cred means no limit check for tmp snapshot */
1527 error = dsl_dataset_snapshot_check_impl(ds, ddsta->ddsta_snapname,
1528 tx, B_FALSE, 0, NULL);
1529 if (error != 0) {
1530 dsl_dataset_rele(ds, FTAG);
1531 return (error);
1532 }
1533
1534 if (spa_version(dp->dp_spa) < SPA_VERSION_USERREFS) {
1535 dsl_dataset_rele(ds, FTAG);
1536 return (SET_ERROR(ENOTSUP));
1537 }
1538 error = dsl_dataset_user_hold_check_one(NULL, ddsta->ddsta_htag,
1539 B_TRUE, tx);
1540 if (error != 0) {
1541 dsl_dataset_rele(ds, FTAG);
1542 return (error);
1543 }
1544
1545 dsl_dataset_rele(ds, FTAG);
1546 return (0);
1547 }
1548
1549 static void
1550 dsl_dataset_snapshot_tmp_sync(void *arg, dmu_tx_t *tx)
1551 {
1552 dsl_dataset_snapshot_tmp_arg_t *ddsta = arg;
1553 dsl_pool_t *dp = dmu_tx_pool(tx);
1554 dsl_dataset_t *ds;
1555
1556 VERIFY0(dsl_dataset_hold(dp, ddsta->ddsta_fsname, FTAG, &ds));
1557
1558 dsl_dataset_snapshot_sync_impl(ds, ddsta->ddsta_snapname, tx);
1559 dsl_dataset_user_hold_sync_one(ds->ds_prev, ddsta->ddsta_htag,
1560 ddsta->ddsta_cleanup_minor, gethrestime_sec(), tx);
1561 dsl_destroy_snapshot_sync_impl(ds->ds_prev, B_TRUE, tx);
1562
1563 dsl_dataset_rele(ds, FTAG);
1564 }
1565
1566 int
1567 dsl_dataset_snapshot_tmp(const char *fsname, const char *snapname,
1568 minor_t cleanup_minor, const char *htag)
1569 {
1570 dsl_dataset_snapshot_tmp_arg_t ddsta;
1571 int error;
1572 spa_t *spa;
1573 boolean_t needsuspend;
1574 void *cookie;
1575
1576 ddsta.ddsta_fsname = fsname;
1577 ddsta.ddsta_snapname = snapname;
1578 ddsta.ddsta_cleanup_minor = cleanup_minor;
1579 ddsta.ddsta_htag = htag;
1580
1581 error = spa_open(fsname, &spa, FTAG);
1582 if (error != 0)
1583 return (error);
1584 needsuspend = (spa_version(spa) < SPA_VERSION_FAST_SNAP);
1585 spa_close(spa, FTAG);
1586
1587 if (needsuspend) {
1588 error = zil_suspend(fsname, &cookie);
1589 if (error != 0)
1590 return (error);
1591 }
1592
1593 error = dsl_sync_task(fsname, dsl_dataset_snapshot_tmp_check,
1594 dsl_dataset_snapshot_tmp_sync, &ddsta, 3, ZFS_SPACE_CHECK_RESERVED);
1595
1596 if (needsuspend)
1597 zil_resume(cookie);
1598 return (error);
1599 }
1600
1601
1602 void
1603 dsl_dataset_sync(dsl_dataset_t *ds, zio_t *zio, dmu_tx_t *tx)
1604 {
1605 ASSERT(dmu_tx_is_syncing(tx));
1606 ASSERT(ds->ds_objset != NULL);
1607 ASSERT(dsl_dataset_phys(ds)->ds_next_snap_obj == 0);
1608
1609 /*
1610 * in case we had to change ds_fsid_guid when we opened it,
1611 * sync it out now.
1612 */
1613 dmu_buf_will_dirty(ds->ds_dbuf, tx);
1614 dsl_dataset_phys(ds)->ds_fsid_guid = ds->ds_fsid_guid;
1615
1616 if (ds->ds_resume_bytes[tx->tx_txg & TXG_MASK] != 0) {
1617 VERIFY0(zap_update(tx->tx_pool->dp_meta_objset,
1618 ds->ds_object, DS_FIELD_RESUME_OBJECT, 8, 1,
1619 &ds->ds_resume_object[tx->tx_txg & TXG_MASK], tx));
1620 VERIFY0(zap_update(tx->tx_pool->dp_meta_objset,
1621 ds->ds_object, DS_FIELD_RESUME_OFFSET, 8, 1,
1622 &ds->ds_resume_offset[tx->tx_txg & TXG_MASK], tx));
1623 VERIFY0(zap_update(tx->tx_pool->dp_meta_objset,
1624 ds->ds_object, DS_FIELD_RESUME_BYTES, 8, 1,
1625 &ds->ds_resume_bytes[tx->tx_txg & TXG_MASK], tx));
1626 ds->ds_resume_object[tx->tx_txg & TXG_MASK] = 0;
1627 ds->ds_resume_offset[tx->tx_txg & TXG_MASK] = 0;
1628 ds->ds_resume_bytes[tx->tx_txg & TXG_MASK] = 0;
1629 }
1630
1631 dmu_objset_sync(ds->ds_objset, zio, tx);
1632
1633 for (spa_feature_t f = 0; f < SPA_FEATURES; f++) {
1634 if (ds->ds_feature_activation_needed[f]) {
1635 if (ds->ds_feature_inuse[f])
1636 continue;
1637 dsl_dataset_activate_feature(ds->ds_object, f, tx);
1638 ds->ds_feature_inuse[f] = B_TRUE;
1639 }
1640 }
1641 }
1642
1643 static void
1644 get_clones_stat(dsl_dataset_t *ds, nvlist_t *nv)
1645 {
1646 uint64_t count = 0;
1647 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
1648 zap_cursor_t zc;
1649 zap_attribute_t za;
1650 nvlist_t *propval = fnvlist_alloc();
1651 nvlist_t *val = fnvlist_alloc();
1652
1653 ASSERT(dsl_pool_config_held(ds->ds_dir->dd_pool));
1654
1655 /*
1656 * There may be missing entries in ds_next_clones_obj
1657 * due to a bug in a previous version of the code.
1658 * Only trust it if it has the right number of entries.
1659 */
1660 if (dsl_dataset_phys(ds)->ds_next_clones_obj != 0) {
1661 VERIFY0(zap_count(mos, dsl_dataset_phys(ds)->ds_next_clones_obj,
1662 &count));
1663 }
1664 if (count != dsl_dataset_phys(ds)->ds_num_children - 1)
1665 goto fail;
1666 for (zap_cursor_init(&zc, mos,
1667 dsl_dataset_phys(ds)->ds_next_clones_obj);
1668 zap_cursor_retrieve(&zc, &za) == 0;
1669 zap_cursor_advance(&zc)) {
1670 dsl_dataset_t *clone;
1671 char buf[ZFS_MAXNAMELEN];
1672 VERIFY0(dsl_dataset_hold_obj(ds->ds_dir->dd_pool,
1673 za.za_first_integer, FTAG, &clone));
1674 dsl_dir_name(clone->ds_dir, buf);
1675 fnvlist_add_boolean(val, buf);
1676 dsl_dataset_rele(clone, FTAG);
1677 }
1678 zap_cursor_fini(&zc);
1679 fnvlist_add_nvlist(propval, ZPROP_VALUE, val);
1680 fnvlist_add_nvlist(nv, zfs_prop_to_name(ZFS_PROP_CLONES), propval);
1681 fail:
1682 nvlist_free(val);
1683 nvlist_free(propval);
1684 }
1685
1686 static void
1687 get_receive_resume_stats(dsl_dataset_t *ds, nvlist_t *nv)
1688 {
1689 dsl_pool_t *dp = ds->ds_dir->dd_pool;
1690
1691 if (dsl_dataset_has_resume_receive_state(ds)) {
1692 char *str;
1693 void *packed;
1694 uint8_t *compressed;
1695 uint64_t val;
1696 nvlist_t *token_nv = fnvlist_alloc();
1697 size_t packed_size, compressed_size;
1698
1699 if (zap_lookup(dp->dp_meta_objset, ds->ds_object,
1700 DS_FIELD_RESUME_FROMGUID, sizeof (val), 1, &val) == 0) {
1701 fnvlist_add_uint64(token_nv, "fromguid", val);
1702 }
1703 if (zap_lookup(dp->dp_meta_objset, ds->ds_object,
1704 DS_FIELD_RESUME_OBJECT, sizeof (val), 1, &val) == 0) {
1705 fnvlist_add_uint64(token_nv, "object", val);
1706 }
1707 if (zap_lookup(dp->dp_meta_objset, ds->ds_object,
1708 DS_FIELD_RESUME_OFFSET, sizeof (val), 1, &val) == 0) {
1709 fnvlist_add_uint64(token_nv, "offset", val);
1710 }
1711 if (zap_lookup(dp->dp_meta_objset, ds->ds_object,
1712 DS_FIELD_RESUME_BYTES, sizeof (val), 1, &val) == 0) {
1713 fnvlist_add_uint64(token_nv, "bytes", val);
1714 }
1715 if (zap_lookup(dp->dp_meta_objset, ds->ds_object,
1716 DS_FIELD_RESUME_TOGUID, sizeof (val), 1, &val) == 0) {
1717 fnvlist_add_uint64(token_nv, "toguid", val);
1718 }
1719 char buf[256];
1720 if (zap_lookup(dp->dp_meta_objset, ds->ds_object,
1721 DS_FIELD_RESUME_TONAME, 1, sizeof (buf), buf) == 0) {
1722 fnvlist_add_string(token_nv, "toname", buf);
1723 }
1724 if (zap_contains(dp->dp_meta_objset, ds->ds_object,
1725 DS_FIELD_RESUME_EMBEDOK) == 0) {
1726 fnvlist_add_boolean(token_nv, "embedok");
1727 }
1728 packed = fnvlist_pack(token_nv, &packed_size);
1729 fnvlist_free(token_nv);
1730 compressed = kmem_alloc(packed_size, KM_SLEEP);
1731
1732 compressed_size = gzip_compress(packed, compressed,
1733 packed_size, packed_size, 6);
1734
1735 zio_cksum_t cksum;
1736 fletcher_4_native(compressed, compressed_size, NULL, &cksum);
1737
1738 str = kmem_alloc(compressed_size * 2 + 1, KM_SLEEP);
1739 for (int i = 0; i < compressed_size; i++) {
1740 (void) sprintf(str + i * 2, "%02x", compressed[i]);
1741 }
1742 str[compressed_size * 2] = '\0';
1743 char *propval = kmem_asprintf("%u-%llx-%llx-%s",
1744 ZFS_SEND_RESUME_TOKEN_VERSION,
1745 (longlong_t)cksum.zc_word[0],
1746 (longlong_t)packed_size, str);
1747 dsl_prop_nvlist_add_string(nv,
1748 ZFS_PROP_RECEIVE_RESUME_TOKEN, propval);
1749 kmem_free(packed, packed_size);
1750 kmem_free(str, compressed_size * 2 + 1);
1751 kmem_free(compressed, packed_size);
1752 strfree(propval);
1753 }
1754 }
1755
1756 void
1757 dsl_dataset_stats(dsl_dataset_t *ds, nvlist_t *nv)
1758 {
1759 dsl_pool_t *dp = ds->ds_dir->dd_pool;
1760 uint64_t refd, avail, uobjs, aobjs, ratio;
1761
1762 ASSERT(dsl_pool_config_held(dp));
1763
1764 ratio = dsl_dataset_phys(ds)->ds_compressed_bytes == 0 ? 100 :
1765 (dsl_dataset_phys(ds)->ds_uncompressed_bytes * 100 /
1766 dsl_dataset_phys(ds)->ds_compressed_bytes);
1767
1768 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFRATIO, ratio);
1769 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_LOGICALREFERENCED,
1770 dsl_dataset_phys(ds)->ds_uncompressed_bytes);
1771
1772 if (ds->ds_is_snapshot) {
1773 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_COMPRESSRATIO, ratio);
1774 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USED,
1775 dsl_dataset_phys(ds)->ds_unique_bytes);
1776 get_clones_stat(ds, nv);
1777 } else {
1778 if (ds->ds_prev != NULL && ds->ds_prev != dp->dp_origin_snap) {
1779 char buf[MAXNAMELEN];
1780 dsl_dataset_name(ds->ds_prev, buf);
1781 dsl_prop_nvlist_add_string(nv, ZFS_PROP_PREV_SNAP, buf);
1782 }
1783
1784 dsl_dir_stats(ds->ds_dir, nv);
1785 }
1786
1787 dsl_dataset_space(ds, &refd, &avail, &uobjs, &aobjs);
1788 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_AVAILABLE, avail);
1789 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFERENCED, refd);
1790
1791 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATION,
1792 dsl_dataset_phys(ds)->ds_creation_time);
1793 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATETXG,
1794 dsl_dataset_phys(ds)->ds_creation_txg);
1795 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFQUOTA,
1796 ds->ds_quota);
1797 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFRESERVATION,
1798 ds->ds_reserved);
1799 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_GUID,
1800 dsl_dataset_phys(ds)->ds_guid);
1801 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_UNIQUE,
1802 dsl_dataset_phys(ds)->ds_unique_bytes);
1803 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_OBJSETID,
1804 ds->ds_object);
1805 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USERREFS,
1806 ds->ds_userrefs);
1807 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_DEFER_DESTROY,
1808 DS_IS_DEFER_DESTROY(ds) ? 1 : 0);
1809
1810 if (dsl_dataset_phys(ds)->ds_prev_snap_obj != 0) {
1811 uint64_t written, comp, uncomp;
1812 dsl_pool_t *dp = ds->ds_dir->dd_pool;
1813 dsl_dataset_t *prev;
1814
1815 int err = dsl_dataset_hold_obj(dp,
1816 dsl_dataset_phys(ds)->ds_prev_snap_obj, FTAG, &prev);
1817 if (err == 0) {
1818 err = dsl_dataset_space_written(prev, ds, &written,
1819 &comp, &uncomp);
1820 dsl_dataset_rele(prev, FTAG);
1821 if (err == 0) {
1822 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_WRITTEN,
1823 written);
1824 }
1825 }
1826 }
1827
1828 if (!dsl_dataset_is_snapshot(ds)) {
1829 /*
1830 * A failed "newfs" (e.g. full) resumable receive leaves
1831 * the stats set on this dataset. Check here for the prop.
1832 */
1833 get_receive_resume_stats(ds, nv);
1834
1835 /*
1836 * A failed incremental resumable receive leaves the
1837 * stats set on our child named "%recv". Check the child
1838 * for the prop.
1839 */
1840 char recvname[ZFS_MAXNAMELEN];
1841 dsl_dataset_t *recv_ds;
1842 dsl_dataset_name(ds, recvname);
1843 (void) strcat(recvname, "/");
1844 (void) strcat(recvname, recv_clone_name);
1845 if (dsl_dataset_hold(dp, recvname, FTAG, &recv_ds) == 0) {
1846 get_receive_resume_stats(recv_ds, nv);
1847 dsl_dataset_rele(recv_ds, FTAG);
1848 }
1849 }
1850 }
1851
1852 void
1853 dsl_dataset_fast_stat(dsl_dataset_t *ds, dmu_objset_stats_t *stat)
1854 {
1855 dsl_pool_t *dp = ds->ds_dir->dd_pool;
1856 ASSERT(dsl_pool_config_held(dp));
1857
1858 stat->dds_creation_txg = dsl_dataset_phys(ds)->ds_creation_txg;
1859 stat->dds_inconsistent =
1860 dsl_dataset_phys(ds)->ds_flags & DS_FLAG_INCONSISTENT;
1861 stat->dds_guid = dsl_dataset_phys(ds)->ds_guid;
1862 stat->dds_origin[0] = '\0';
1863 if (ds->ds_is_snapshot) {
1864 stat->dds_is_snapshot = B_TRUE;
1865 stat->dds_num_clones =
1866 dsl_dataset_phys(ds)->ds_num_children - 1;
1867 } else {
1868 stat->dds_is_snapshot = B_FALSE;
1869 stat->dds_num_clones = 0;
1870
1871 if (dsl_dir_is_clone(ds->ds_dir)) {
1872 dsl_dataset_t *ods;
1873
1874 VERIFY0(dsl_dataset_hold_obj(dp,
1875 dsl_dir_phys(ds->ds_dir)->dd_origin_obj,
1876 FTAG, &ods));
1877 dsl_dataset_name(ods, stat->dds_origin);
1878 dsl_dataset_rele(ods, FTAG);
1879 }
1880 }
1881 }
1882
1883 uint64_t
1884 dsl_dataset_fsid_guid(dsl_dataset_t *ds)
1885 {
1886 return (ds->ds_fsid_guid);
1887 }
1888
1889 void
1890 dsl_dataset_space(dsl_dataset_t *ds,
1891 uint64_t *refdbytesp, uint64_t *availbytesp,
1892 uint64_t *usedobjsp, uint64_t *availobjsp)
1893 {
1894 *refdbytesp = dsl_dataset_phys(ds)->ds_referenced_bytes;
1895 *availbytesp = dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE);
1896 if (ds->ds_reserved > dsl_dataset_phys(ds)->ds_unique_bytes)
1897 *availbytesp +=
1898 ds->ds_reserved - dsl_dataset_phys(ds)->ds_unique_bytes;
1899 if (ds->ds_quota != 0) {
1900 /*
1901 * Adjust available bytes according to refquota
1902 */
1903 if (*refdbytesp < ds->ds_quota)
1904 *availbytesp = MIN(*availbytesp,
1905 ds->ds_quota - *refdbytesp);
1906 else
1907 *availbytesp = 0;
1908 }
1909 *usedobjsp = BP_GET_FILL(&dsl_dataset_phys(ds)->ds_bp);
1910 *availobjsp = DN_MAX_OBJECT - *usedobjsp;
1911 }
1912
1913 boolean_t
1914 dsl_dataset_modified_since_snap(dsl_dataset_t *ds, dsl_dataset_t *snap)
1915 {
1916 dsl_pool_t *dp = ds->ds_dir->dd_pool;
1917
1918 ASSERT(dsl_pool_config_held(dp));
1919 if (snap == NULL)
1920 return (B_FALSE);
1921 if (dsl_dataset_phys(ds)->ds_bp.blk_birth >
1922 dsl_dataset_phys(snap)->ds_creation_txg) {
1923 objset_t *os, *os_snap;
1924 /*
1925 * It may be that only the ZIL differs, because it was
1926 * reset in the head. Don't count that as being
1927 * modified.
1928 */
1929 if (dmu_objset_from_ds(ds, &os) != 0)
1930 return (B_TRUE);
1931 if (dmu_objset_from_ds(snap, &os_snap) != 0)
1932 return (B_TRUE);
1933 return (bcmp(&os->os_phys->os_meta_dnode,
1934 &os_snap->os_phys->os_meta_dnode,
1935 sizeof (os->os_phys->os_meta_dnode)) != 0);
1936 }
1937 return (B_FALSE);
1938 }
1939
1940 typedef struct dsl_dataset_rename_snapshot_arg {
1941 const char *ddrsa_fsname;
1942 const char *ddrsa_oldsnapname;
1943 const char *ddrsa_newsnapname;
1944 boolean_t ddrsa_recursive;
1945 dmu_tx_t *ddrsa_tx;
1946 } dsl_dataset_rename_snapshot_arg_t;
1947
1948 /* ARGSUSED */
1949 static int
1950 dsl_dataset_rename_snapshot_check_impl(dsl_pool_t *dp,
1951 dsl_dataset_t *hds, void *arg)
1952 {
1953 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg;
1954 int error;
1955 uint64_t val;
1956
1957 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_oldsnapname, &val);
1958 if (error != 0) {
1959 /* ignore nonexistent snapshots */
1960 return (error == ENOENT ? 0 : error);
1961 }
1962
1963 /* new name should not exist */
1964 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_newsnapname, &val);
1965 if (error == 0)
1966 error = SET_ERROR(EEXIST);
1967 else if (error == ENOENT)
1968 error = 0;
1969
1970 /* dataset name + 1 for the "@" + the new snapshot name must fit */
1971 if (dsl_dir_namelen(hds->ds_dir) + 1 +
1972 strlen(ddrsa->ddrsa_newsnapname) >= MAXNAMELEN)
1973 error = SET_ERROR(ENAMETOOLONG);
1974
1975 return (error);
1976 }
1977
1978 static int
1979 dsl_dataset_rename_snapshot_check(void *arg, dmu_tx_t *tx)
1980 {
1981 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg;
1982 dsl_pool_t *dp = dmu_tx_pool(tx);
1983 dsl_dataset_t *hds;
1984 int error;
1985
1986 error = dsl_dataset_hold(dp, ddrsa->ddrsa_fsname, FTAG, &hds);
1987 if (error != 0)
1988 return (error);
1989
1990 if (ddrsa->ddrsa_recursive) {
1991 error = dmu_objset_find_dp(dp, hds->ds_dir->dd_object,
1992 dsl_dataset_rename_snapshot_check_impl, ddrsa,
1993 DS_FIND_CHILDREN);
1994 } else {
1995 error = dsl_dataset_rename_snapshot_check_impl(dp, hds, ddrsa);
1996 }
1997 dsl_dataset_rele(hds, FTAG);
1998 return (error);
1999 }
2000
2001 static int
2002 dsl_dataset_rename_snapshot_sync_impl(dsl_pool_t *dp,
2003 dsl_dataset_t *hds, void *arg)
2004 {
2005 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg;
2006 dsl_dataset_t *ds;
2007 uint64_t val;
2008 dmu_tx_t *tx = ddrsa->ddrsa_tx;
2009 int error;
2010
2011 error = dsl_dataset_snap_lookup(hds, ddrsa->ddrsa_oldsnapname, &val);
2012 ASSERT(error == 0 || error == ENOENT);
2013 if (error == ENOENT) {
2014 /* ignore nonexistent snapshots */
2015 return (0);
2016 }
2017
2018 VERIFY0(dsl_dataset_hold_obj(dp, val, FTAG, &ds));
2019
2020 /* log before we change the name */
2021 spa_history_log_internal_ds(ds, "rename", tx,
2022 "-> @%s", ddrsa->ddrsa_newsnapname);
2023
2024 VERIFY0(dsl_dataset_snap_remove(hds, ddrsa->ddrsa_oldsnapname, tx,
2025 B_FALSE));
2026 mutex_enter(&ds->ds_lock);
2027 (void) strcpy(ds->ds_snapname, ddrsa->ddrsa_newsnapname);
2028 mutex_exit(&ds->ds_lock);
2029 VERIFY0(zap_add(dp->dp_meta_objset,
2030 dsl_dataset_phys(hds)->ds_snapnames_zapobj,
2031 ds->ds_snapname, 8, 1, &ds->ds_object, tx));
2032
2033 dsl_dataset_rele(ds, FTAG);
2034 return (0);
2035 }
2036
2037 static void
2038 dsl_dataset_rename_snapshot_sync(void *arg, dmu_tx_t *tx)
2039 {
2040 dsl_dataset_rename_snapshot_arg_t *ddrsa = arg;
2041 dsl_pool_t *dp = dmu_tx_pool(tx);
2042 dsl_dataset_t *hds;
2043
2044 VERIFY0(dsl_dataset_hold(dp, ddrsa->ddrsa_fsname, FTAG, &hds));
2045 ddrsa->ddrsa_tx = tx;
2046 if (ddrsa->ddrsa_recursive) {
2047 VERIFY0(dmu_objset_find_dp(dp, hds->ds_dir->dd_object,
2048 dsl_dataset_rename_snapshot_sync_impl, ddrsa,
2049 DS_FIND_CHILDREN));
2050 } else {
2051 VERIFY0(dsl_dataset_rename_snapshot_sync_impl(dp, hds, ddrsa));
2052 }
2053 dsl_dataset_rele(hds, FTAG);
2054 }
2055
2056 int
2057 dsl_dataset_rename_snapshot(const char *fsname,
2058 const char *oldsnapname, const char *newsnapname, boolean_t recursive)
2059 {
2060 dsl_dataset_rename_snapshot_arg_t ddrsa;
2061
2062 ddrsa.ddrsa_fsname = fsname;
2063 ddrsa.ddrsa_oldsnapname = oldsnapname;
2064 ddrsa.ddrsa_newsnapname = newsnapname;
2065 ddrsa.ddrsa_recursive = recursive;
2066
2067 return (dsl_sync_task(fsname, dsl_dataset_rename_snapshot_check,
2068 dsl_dataset_rename_snapshot_sync, &ddrsa,
2069 1, ZFS_SPACE_CHECK_RESERVED));
2070 }
2071
2072 /*
2073 * If we're doing an ownership handoff, we need to make sure that there is
2074 * only one long hold on the dataset. We're not allowed to change anything here
2075 * so we don't permanently release the long hold or regular hold here. We want
2076 * to do this only when syncing to avoid the dataset unexpectedly going away
2077 * when we release the long hold.
2078 */
2079 static int
2080 dsl_dataset_handoff_check(dsl_dataset_t *ds, void *owner, dmu_tx_t *tx)
2081 {
2082 boolean_t held;
2083
2084 if (!dmu_tx_is_syncing(tx))
2085 return (0);
2086
2087 if (owner != NULL) {
2088 VERIFY3P(ds->ds_owner, ==, owner);
2089 dsl_dataset_long_rele(ds, owner);
2090 }
2091
2092 held = dsl_dataset_long_held(ds);
2093
2094 if (owner != NULL)
2095 dsl_dataset_long_hold(ds, owner);
2096
2097 if (held)
2098 return (SET_ERROR(EBUSY));
2099
2100 return (0);
2101 }
2102
2103 typedef struct dsl_dataset_rollback_arg {
2104 const char *ddra_fsname;
2105 void *ddra_owner;
2106 nvlist_t *ddra_result;
2107 } dsl_dataset_rollback_arg_t;
2108
2109 static int
2110 dsl_dataset_rollback_check(void *arg, dmu_tx_t *tx)
2111 {
2112 dsl_dataset_rollback_arg_t *ddra = arg;
2113 dsl_pool_t *dp = dmu_tx_pool(tx);
2114 dsl_dataset_t *ds;
2115 int64_t unused_refres_delta;
2116 int error;
2117
2118 error = dsl_dataset_hold(dp, ddra->ddra_fsname, FTAG, &ds);
2119 if (error != 0)
2120 return (error);
2121
2122 /* must not be a snapshot */
2123 if (ds->ds_is_snapshot) {
2124 dsl_dataset_rele(ds, FTAG);
2125 return (SET_ERROR(EINVAL));
2126 }
2127
2128 /* must have a most recent snapshot */
2129 if (dsl_dataset_phys(ds)->ds_prev_snap_txg < TXG_INITIAL) {
2130 dsl_dataset_rele(ds, FTAG);
2131 return (SET_ERROR(EINVAL));
2132 }
2133
2134 /* must not have any bookmarks after the most recent snapshot */
2135 nvlist_t *proprequest = fnvlist_alloc();
2136 fnvlist_add_boolean(proprequest, zfs_prop_to_name(ZFS_PROP_CREATETXG));
2137 nvlist_t *bookmarks = fnvlist_alloc();
2138 error = dsl_get_bookmarks_impl(ds, proprequest, bookmarks);
2139 fnvlist_free(proprequest);
2140 if (error != 0)
2141 return (error);
2142 for (nvpair_t *pair = nvlist_next_nvpair(bookmarks, NULL);
2143 pair != NULL; pair = nvlist_next_nvpair(bookmarks, pair)) {
2144 nvlist_t *valuenv =
2145 fnvlist_lookup_nvlist(fnvpair_value_nvlist(pair),
2146 zfs_prop_to_name(ZFS_PROP_CREATETXG));
2147 uint64_t createtxg = fnvlist_lookup_uint64(valuenv, "value");
2148 if (createtxg > dsl_dataset_phys(ds)->ds_prev_snap_txg) {
2149 fnvlist_free(bookmarks);
2150 dsl_dataset_rele(ds, FTAG);
2151 return (SET_ERROR(EEXIST));
2152 }
2153 }
2154 fnvlist_free(bookmarks);
2155
2156 error = dsl_dataset_handoff_check(ds, ddra->ddra_owner, tx);
2157 if (error != 0) {
2158 dsl_dataset_rele(ds, FTAG);
2159 return (error);
2160 }
2161
2162 /*
2163 * Check if the snap we are rolling back to uses more than
2164 * the refquota.
2165 */
2166 if (ds->ds_quota != 0 &&
2167 dsl_dataset_phys(ds->ds_prev)->ds_referenced_bytes > ds->ds_quota) {
2168 dsl_dataset_rele(ds, FTAG);
2169 return (SET_ERROR(EDQUOT));
2170 }
2171
2172 /*
2173 * When we do the clone swap, we will temporarily use more space
2174 * due to the refreservation (the head will no longer have any
2175 * unique space, so the entire amount of the refreservation will need
2176 * to be free). We will immediately destroy the clone, freeing
2177 * this space, but the freeing happens over many txg's.
2178 */
2179 unused_refres_delta = (int64_t)MIN(ds->ds_reserved,
2180 dsl_dataset_phys(ds)->ds_unique_bytes);
2181
2182 if (unused_refres_delta > 0 &&
2183 unused_refres_delta >
2184 dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE)) {
2185 dsl_dataset_rele(ds, FTAG);
2186 return (SET_ERROR(ENOSPC));
2187 }
2188
2189 dsl_dataset_rele(ds, FTAG);
2190 return (0);
2191 }
2192
2193 static void
2194 dsl_dataset_rollback_sync(void *arg, dmu_tx_t *tx)
2195 {
2196 dsl_dataset_rollback_arg_t *ddra = arg;
2197 dsl_pool_t *dp = dmu_tx_pool(tx);
2198 dsl_dataset_t *ds, *clone;
2199 uint64_t cloneobj;
2200 char namebuf[ZFS_MAXNAMELEN];
2201
2202 VERIFY0(dsl_dataset_hold(dp, ddra->ddra_fsname, FTAG, &ds));
2203
2204 dsl_dataset_name(ds->ds_prev, namebuf);
2205 fnvlist_add_string(ddra->ddra_result, "target", namebuf);
2206
2207 cloneobj = dsl_dataset_create_sync(ds->ds_dir, "%rollback",
2208 ds->ds_prev, DS_CREATE_FLAG_NODIRTY, kcred, tx);
2209
2210 VERIFY0(dsl_dataset_hold_obj(dp, cloneobj, FTAG, &clone));
2211
2212 dsl_dataset_clone_swap_sync_impl(clone, ds, tx);
2213 dsl_dataset_zero_zil(ds, tx);
2214
2215 dsl_destroy_head_sync_impl(clone, tx);
2216
2217 dsl_dataset_rele(clone, FTAG);
2218 dsl_dataset_rele(ds, FTAG);
2219 }
2220
2221 /*
2222 * Rolls back the given filesystem or volume to the most recent snapshot.
2223 * The name of the most recent snapshot will be returned under key "target"
2224 * in the result nvlist.
2225 *
2226 * If owner != NULL:
2227 * - The existing dataset MUST be owned by the specified owner at entry
2228 * - Upon return, dataset will still be held by the same owner, whether we
2229 * succeed or not.
2230 *
2231 * This mode is required any time the existing filesystem is mounted. See
2232 * notes above zfs_suspend_fs() for further details.
2233 */
2234 int
2235 dsl_dataset_rollback(const char *fsname, void *owner, nvlist_t *result)
2236 {
2237 dsl_dataset_rollback_arg_t ddra;
2238
2239 ddra.ddra_fsname = fsname;
2240 ddra.ddra_owner = owner;
2241 ddra.ddra_result = result;
2242
2243 return (dsl_sync_task(fsname, dsl_dataset_rollback_check,
2244 dsl_dataset_rollback_sync, &ddra,
2245 1, ZFS_SPACE_CHECK_RESERVED));
2246 }
2247
2248 struct promotenode {
2249 list_node_t link;
2250 dsl_dataset_t *ds;
2251 };
2252
2253 typedef struct dsl_dataset_promote_arg {
2254 const char *ddpa_clonename;
2255 dsl_dataset_t *ddpa_clone;
2256 list_t shared_snaps, origin_snaps, clone_snaps;
2257 dsl_dataset_t *origin_origin; /* origin of the origin */
2258 uint64_t used, comp, uncomp, unique, cloneusedsnap, originusedsnap;
2259 char *err_ds;
2260 cred_t *cr;
2261 } dsl_dataset_promote_arg_t;
2262
2263 static int snaplist_space(list_t *l, uint64_t mintxg, uint64_t *spacep);
2264 static int promote_hold(dsl_dataset_promote_arg_t *ddpa, dsl_pool_t *dp,
2265 void *tag);
2266 static void promote_rele(dsl_dataset_promote_arg_t *ddpa, void *tag);
2267
2268 static int
2269 dsl_dataset_promote_check(void *arg, dmu_tx_t *tx)
2270 {
2271 dsl_dataset_promote_arg_t *ddpa = arg;
2272 dsl_pool_t *dp = dmu_tx_pool(tx);
2273 dsl_dataset_t *hds;
2274 struct promotenode *snap;
2275 dsl_dataset_t *origin_ds;
2276 int err;
2277 uint64_t unused;
2278 uint64_t ss_mv_cnt;
2279 size_t max_snap_len;
2280
2281 err = promote_hold(ddpa, dp, FTAG);
2282 if (err != 0)
2283 return (err);
2284
2285 hds = ddpa->ddpa_clone;
2286 max_snap_len = MAXNAMELEN - strlen(ddpa->ddpa_clonename) - 1;
2287
2288 if (dsl_dataset_phys(hds)->ds_flags & DS_FLAG_NOPROMOTE) {
2289 promote_rele(ddpa, FTAG);
2290 return (SET_ERROR(EXDEV));
2291 }
2292
2293 /*
2294 * Compute and check the amount of space to transfer. Since this is
2295 * so expensive, don't do the preliminary check.
2296 */
2297 if (!dmu_tx_is_syncing(tx)) {
2298 promote_rele(ddpa, FTAG);
2299 return (0);
2300 }
2301
2302 snap = list_head(&ddpa->shared_snaps);
2303 origin_ds = snap->ds;
2304
2305 /* compute origin's new unique space */
2306 snap = list_tail(&ddpa->clone_snaps);
2307 ASSERT3U(dsl_dataset_phys(snap->ds)->ds_prev_snap_obj, ==,
2308 origin_ds->ds_object);
2309 dsl_deadlist_space_range(&snap->ds->ds_deadlist,
2310 dsl_dataset_phys(origin_ds)->ds_prev_snap_txg, UINT64_MAX,
2311 &ddpa->unique, &unused, &unused);
2312
2313 /*
2314 * Walk the snapshots that we are moving
2315 *
2316 * Compute space to transfer. Consider the incremental changes
2317 * to used by each snapshot:
2318 * (my used) = (prev's used) + (blocks born) - (blocks killed)
2319 * So each snapshot gave birth to:
2320 * (blocks born) = (my used) - (prev's used) + (blocks killed)
2321 * So a sequence would look like:
2322 * (uN - u(N-1) + kN) + ... + (u1 - u0 + k1) + (u0 - 0 + k0)
2323 * Which simplifies to:
2324 * uN + kN + kN-1 + ... + k1 + k0
2325 * Note however, if we stop before we reach the ORIGIN we get:
2326 * uN + kN + kN-1 + ... + kM - uM-1
2327 */
2328 ss_mv_cnt = 0;
2329 ddpa->used = dsl_dataset_phys(origin_ds)->ds_referenced_bytes;
2330 ddpa->comp = dsl_dataset_phys(origin_ds)->ds_compressed_bytes;
2331 ddpa->uncomp = dsl_dataset_phys(origin_ds)->ds_uncompressed_bytes;
2332 for (snap = list_head(&ddpa->shared_snaps); snap;
2333 snap = list_next(&ddpa->shared_snaps, snap)) {
2334 uint64_t val, dlused, dlcomp, dluncomp;
2335 dsl_dataset_t *ds = snap->ds;
2336
2337 ss_mv_cnt++;
2338
2339 /*
2340 * If there are long holds, we won't be able to evict
2341 * the objset.
2342 */
2343 if (dsl_dataset_long_held(ds)) {
2344 err = SET_ERROR(EBUSY);
2345 goto out;
2346 }
2347
2348 /* Check that the snapshot name does not conflict */
2349 VERIFY0(dsl_dataset_get_snapname(ds));
2350 if (strlen(ds->ds_snapname) >= max_snap_len) {
2351 err = SET_ERROR(ENAMETOOLONG);
2352 goto out;
2353 }
2354 err = dsl_dataset_snap_lookup(hds, ds->ds_snapname, &val);
2355 if (err == 0) {
2356 (void) strcpy(ddpa->err_ds, snap->ds->ds_snapname);
2357 err = SET_ERROR(EEXIST);
2358 goto out;
2359 }
2360 if (err != ENOENT)
2361 goto out;
2362
2363 /* The very first snapshot does not have a deadlist */
2364 if (dsl_dataset_phys(ds)->ds_prev_snap_obj == 0)
2365 continue;
2366
2367 dsl_deadlist_space(&ds->ds_deadlist,
2368 &dlused, &dlcomp, &dluncomp);
2369 ddpa->used += dlused;
2370 ddpa->comp += dlcomp;
2371 ddpa->uncomp += dluncomp;
2372 }
2373
2374 /*
2375 * If we are a clone of a clone then we never reached ORIGIN,
2376 * so we need to subtract out the clone origin's used space.
2377 */
2378 if (ddpa->origin_origin) {
2379 ddpa->used -=
2380 dsl_dataset_phys(ddpa->origin_origin)->ds_referenced_bytes;
2381 ddpa->comp -=
2382 dsl_dataset_phys(ddpa->origin_origin)->ds_compressed_bytes;
2383 ddpa->uncomp -=
2384 dsl_dataset_phys(ddpa->origin_origin)->
2385 ds_uncompressed_bytes;
2386 }
2387
2388 /* Check that there is enough space and limit headroom here */
2389 err = dsl_dir_transfer_possible(origin_ds->ds_dir, hds->ds_dir,
2390 0, ss_mv_cnt, ddpa->used, ddpa->cr);
2391 if (err != 0)
2392 goto out;
2393
2394 /*
2395 * Compute the amounts of space that will be used by snapshots
2396 * after the promotion (for both origin and clone). For each,
2397 * it is the amount of space that will be on all of their
2398 * deadlists (that was not born before their new origin).
2399 */
2400 if (dsl_dir_phys(hds->ds_dir)->dd_flags & DD_FLAG_USED_BREAKDOWN) {
2401 uint64_t space;
2402
2403 /*
2404 * Note, typically this will not be a clone of a clone,
2405 * so dd_origin_txg will be < TXG_INITIAL, so
2406 * these snaplist_space() -> dsl_deadlist_space_range()
2407 * calls will be fast because they do not have to
2408 * iterate over all bps.
2409 */
2410 snap = list_head(&ddpa->origin_snaps);
2411 err = snaplist_space(&ddpa->shared_snaps,
2412 snap->ds->ds_dir->dd_origin_txg, &ddpa->cloneusedsnap);
2413 if (err != 0)
2414 goto out;
2415
2416 err = snaplist_space(&ddpa->clone_snaps,
2417 snap->ds->ds_dir->dd_origin_txg, &space);
2418 if (err != 0)
2419 goto out;
2420 ddpa->cloneusedsnap += space;
2421 }
2422 if (dsl_dir_phys(origin_ds->ds_dir)->dd_flags &
2423 DD_FLAG_USED_BREAKDOWN) {
2424 err = snaplist_space(&ddpa->origin_snaps,
2425 dsl_dataset_phys(origin_ds)->ds_creation_txg,
2426 &ddpa->originusedsnap);
2427 if (err != 0)
2428 goto out;
2429 }
2430
2431 out:
2432 promote_rele(ddpa, FTAG);
2433 return (err);
2434 }
2435
2436 static void
2437 dsl_dataset_promote_sync(void *arg, dmu_tx_t *tx)
2438 {
2439 dsl_dataset_promote_arg_t *ddpa = arg;
2440 dsl_pool_t *dp = dmu_tx_pool(tx);
2441 dsl_dataset_t *hds;
2442 struct promotenode *snap;
2443 dsl_dataset_t *origin_ds;
2444 dsl_dataset_t *origin_head;
2445 dsl_dir_t *dd;
2446 dsl_dir_t *odd = NULL;
2447 uint64_t oldnext_obj;
2448 int64_t delta;
2449
2450 VERIFY0(promote_hold(ddpa, dp, FTAG));
2451 hds = ddpa->ddpa_clone;
2452
2453 ASSERT0(dsl_dataset_phys(hds)->ds_flags & DS_FLAG_NOPROMOTE);
2454
2455 snap = list_head(&ddpa->shared_snaps);
2456 origin_ds = snap->ds;
2457 dd = hds->ds_dir;
2458
2459 snap = list_head(&ddpa->origin_snaps);
2460 origin_head = snap->ds;
2461
2462 /*
2463 * We need to explicitly open odd, since origin_ds's dd will be
2464 * changing.
2465 */
2466 VERIFY0(dsl_dir_hold_obj(dp, origin_ds->ds_dir->dd_object,
2467 NULL, FTAG, &odd));
2468
2469 /* change origin's next snap */
2470 dmu_buf_will_dirty(origin_ds->ds_dbuf, tx);
2471 oldnext_obj = dsl_dataset_phys(origin_ds)->ds_next_snap_obj;
2472 snap = list_tail(&ddpa->clone_snaps);
2473 ASSERT3U(dsl_dataset_phys(snap->ds)->ds_prev_snap_obj, ==,
2474 origin_ds->ds_object);
2475 dsl_dataset_phys(origin_ds)->ds_next_snap_obj = snap->ds->ds_object;
2476
2477 /* change the origin's next clone */
2478 if (dsl_dataset_phys(origin_ds)->ds_next_clones_obj) {
2479 dsl_dataset_remove_from_next_clones(origin_ds,
2480 snap->ds->ds_object, tx);
2481 VERIFY0(zap_add_int(dp->dp_meta_objset,
2482 dsl_dataset_phys(origin_ds)->ds_next_clones_obj,
2483 oldnext_obj, tx));
2484 }
2485
2486 /* change origin */
2487 dmu_buf_will_dirty(dd->dd_dbuf, tx);
2488 ASSERT3U(dsl_dir_phys(dd)->dd_origin_obj, ==, origin_ds->ds_object);
2489 dsl_dir_phys(dd)->dd_origin_obj = dsl_dir_phys(odd)->dd_origin_obj;
2490 dd->dd_origin_txg = origin_head->ds_dir->dd_origin_txg;
2491 dmu_buf_will_dirty(odd->dd_dbuf, tx);
2492 dsl_dir_phys(odd)->dd_origin_obj = origin_ds->ds_object;
2493 origin_head->ds_dir->dd_origin_txg =
2494 dsl_dataset_phys(origin_ds)->ds_creation_txg;
2495
2496 /* change dd_clone entries */
2497 if (spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) {
2498 VERIFY0(zap_remove_int(dp->dp_meta_objset,
2499 dsl_dir_phys(odd)->dd_clones, hds->ds_object, tx));
2500 VERIFY0(zap_add_int(dp->dp_meta_objset,
2501 dsl_dir_phys(ddpa->origin_origin->ds_dir)->dd_clones,
2502 hds->ds_object, tx));
2503
2504 VERIFY0(zap_remove_int(dp->dp_meta_objset,
2505 dsl_dir_phys(ddpa->origin_origin->ds_dir)->dd_clones,
2506 origin_head->ds_object, tx));
2507 if (dsl_dir_phys(dd)->dd_clones == 0) {
2508 dsl_dir_phys(dd)->dd_clones =
2509 zap_create(dp->dp_meta_objset, DMU_OT_DSL_CLONES,
2510 DMU_OT_NONE, 0, tx);
2511 }
2512 VERIFY0(zap_add_int(dp->dp_meta_objset,
2513 dsl_dir_phys(dd)->dd_clones, origin_head->ds_object, tx));
2514 }
2515
2516 /* move snapshots to this dir */
2517 for (snap = list_head(&ddpa->shared_snaps); snap;
2518 snap = list_next(&ddpa->shared_snaps, snap)) {
2519 dsl_dataset_t *ds = snap->ds;
2520
2521 /*
2522 * Property callbacks are registered to a particular
2523 * dsl_dir. Since ours is changing, evict the objset
2524 * so that they will be unregistered from the old dsl_dir.
2525 */
2526 if (ds->ds_objset) {
2527 dmu_objset_evict(ds->ds_objset);
2528 ds->ds_objset = NULL;
2529 }
2530
2531 /* move snap name entry */
2532 VERIFY0(dsl_dataset_get_snapname(ds));
2533 VERIFY0(dsl_dataset_snap_remove(origin_head,
2534 ds->ds_snapname, tx, B_TRUE));
2535 VERIFY0(zap_add(dp->dp_meta_objset,
2536 dsl_dataset_phys(hds)->ds_snapnames_zapobj, ds->ds_snapname,
2537 8, 1, &ds->ds_object, tx));
2538 dsl_fs_ss_count_adjust(hds->ds_dir, 1,
2539 DD_FIELD_SNAPSHOT_COUNT, tx);
2540
2541 /* change containing dsl_dir */
2542 dmu_buf_will_dirty(ds->ds_dbuf, tx);
2543 ASSERT3U(dsl_dataset_phys(ds)->ds_dir_obj, ==, odd->dd_object);
2544 dsl_dataset_phys(ds)->ds_dir_obj = dd->dd_object;
2545 ASSERT3P(ds->ds_dir, ==, odd);
2546 dsl_dir_rele(ds->ds_dir, ds);
2547 VERIFY0(dsl_dir_hold_obj(dp, dd->dd_object,
2548 NULL, ds, &ds->ds_dir));
2549
2550 /* move any clone references */
2551 if (dsl_dataset_phys(ds)->ds_next_clones_obj &&
2552 spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) {
2553 zap_cursor_t zc;
2554 zap_attribute_t za;
2555
2556 for (zap_cursor_init(&zc, dp->dp_meta_objset,
2557 dsl_dataset_phys(ds)->ds_next_clones_obj);
2558 zap_cursor_retrieve(&zc, &za) == 0;
2559 zap_cursor_advance(&zc)) {
2560 dsl_dataset_t *cnds;
2561 uint64_t o;
2562
2563 if (za.za_first_integer == oldnext_obj) {
2564 /*
2565 * We've already moved the
2566 * origin's reference.
2567 */
2568 continue;
2569 }
2570
2571 VERIFY0(dsl_dataset_hold_obj(dp,
2572 za.za_first_integer, FTAG, &cnds));
2573 o = dsl_dir_phys(cnds->ds_dir)->
2574 dd_head_dataset_obj;
2575
2576 VERIFY0(zap_remove_int(dp->dp_meta_objset,
2577 dsl_dir_phys(odd)->dd_clones, o, tx));
2578 VERIFY0(zap_add_int(dp->dp_meta_objset,
2579 dsl_dir_phys(dd)->dd_clones, o, tx));
2580 dsl_dataset_rele(cnds, FTAG);
2581 }
2582 zap_cursor_fini(&zc);
2583 }
2584
2585 ASSERT(!dsl_prop_hascb(ds));
2586 }
2587
2588 /*
2589 * Change space accounting.
2590 * Note, pa->*usedsnap and dd_used_breakdown[SNAP] will either
2591 * both be valid, or both be 0 (resulting in delta == 0). This
2592 * is true for each of {clone,origin} independently.
2593 */
2594
2595 delta = ddpa->cloneusedsnap -
2596 dsl_dir_phys(dd)->dd_used_breakdown[DD_USED_SNAP];
2597 ASSERT3S(delta, >=, 0);
2598 ASSERT3U(ddpa->used, >=, delta);
2599 dsl_dir_diduse_space(dd, DD_USED_SNAP, delta, 0, 0, tx);
2600 dsl_dir_diduse_space(dd, DD_USED_HEAD,
2601 ddpa->used - delta, ddpa->comp, ddpa->uncomp, tx);
2602
2603 delta = ddpa->originusedsnap -
2604 dsl_dir_phys(odd)->dd_used_breakdown[DD_USED_SNAP];
2605 ASSERT3S(delta, <=, 0);
2606 ASSERT3U(ddpa->used, >=, -delta);
2607 dsl_dir_diduse_space(odd, DD_USED_SNAP, delta, 0, 0, tx);
2608 dsl_dir_diduse_space(odd, DD_USED_HEAD,
2609 -ddpa->used - delta, -ddpa->comp, -ddpa->uncomp, tx);
2610
2611 dsl_dataset_phys(origin_ds)->ds_unique_bytes = ddpa->unique;
2612
2613 /* log history record */
2614 spa_history_log_internal_ds(hds, "promote", tx, "");
2615
2616 dsl_dir_rele(odd, FTAG);
2617 promote_rele(ddpa, FTAG);
2618 }
2619
2620 /*
2621 * Make a list of dsl_dataset_t's for the snapshots between first_obj
2622 * (exclusive) and last_obj (inclusive). The list will be in reverse
2623 * order (last_obj will be the list_head()). If first_obj == 0, do all
2624 * snapshots back to this dataset's origin.
2625 */
2626 static int
2627 snaplist_make(dsl_pool_t *dp,
2628 uint64_t first_obj, uint64_t last_obj, list_t *l, void *tag)
2629 {
2630 uint64_t obj = last_obj;
2631
2632 list_create(l, sizeof (struct promotenode),
2633 offsetof(struct promotenode, link));
2634
2635 while (obj != first_obj) {
2636 dsl_dataset_t *ds;
2637 struct promotenode *snap;
2638 int err;
2639
2640 err = dsl_dataset_hold_obj(dp, obj, tag, &ds);
2641 ASSERT(err != ENOENT);
2642 if (err != 0)
2643 return (err);
2644
2645 if (first_obj == 0)
2646 first_obj = dsl_dir_phys(ds->ds_dir)->dd_origin_obj;
2647
2648 snap = kmem_alloc(sizeof (*snap), KM_SLEEP);
2649 snap->ds = ds;
2650 list_insert_tail(l, snap);
2651 obj = dsl_dataset_phys(ds)->ds_prev_snap_obj;
2652 }
2653
2654 return (0);
2655 }
2656
2657 static int
2658 snaplist_space(list_t *l, uint64_t mintxg, uint64_t *spacep)
2659 {
2660 struct promotenode *snap;
2661
2662 *spacep = 0;
2663 for (snap = list_head(l); snap; snap = list_next(l, snap)) {
2664 uint64_t used, comp, uncomp;
2665 dsl_deadlist_space_range(&snap->ds->ds_deadlist,
2666 mintxg, UINT64_MAX, &used, &comp, &uncomp);
2667 *spacep += used;
2668 }
2669 return (0);
2670 }
2671
2672 static void
2673 snaplist_destroy(list_t *l, void *tag)
2674 {
2675 struct promotenode *snap;
2676
2677 if (l == NULL || !list_link_active(&l->list_head))
2678 return;
2679
2680 while ((snap = list_tail(l)) != NULL) {
2681 list_remove(l, snap);
2682 dsl_dataset_rele(snap->ds, tag);
2683 kmem_free(snap, sizeof (*snap));
2684 }
2685 list_destroy(l);
2686 }
2687
2688 static int
2689 promote_hold(dsl_dataset_promote_arg_t *ddpa, dsl_pool_t *dp, void *tag)
2690 {
2691 int error;
2692 dsl_dir_t *dd;
2693 struct promotenode *snap;
2694
2695 error = dsl_dataset_hold(dp, ddpa->ddpa_clonename, tag,
2696 &ddpa->ddpa_clone);
2697 if (error != 0)
2698 return (error);
2699 dd = ddpa->ddpa_clone->ds_dir;
2700
2701 if (ddpa->ddpa_clone->ds_is_snapshot ||
2702 !dsl_dir_is_clone(dd)) {
2703 dsl_dataset_rele(ddpa->ddpa_clone, tag);
2704 return (SET_ERROR(EINVAL));
2705 }
2706
2707 error = snaplist_make(dp, 0, dsl_dir_phys(dd)->dd_origin_obj,
2708 &ddpa->shared_snaps, tag);
2709 if (error != 0)
2710 goto out;
2711
2712 error = snaplist_make(dp, 0, ddpa->ddpa_clone->ds_object,
2713 &ddpa->clone_snaps, tag);
2714 if (error != 0)
2715 goto out;
2716
2717 snap = list_head(&ddpa->shared_snaps);
2718 ASSERT3U(snap->ds->ds_object, ==, dsl_dir_phys(dd)->dd_origin_obj);
2719 error = snaplist_make(dp, dsl_dir_phys(dd)->dd_origin_obj,
2720 dsl_dir_phys(snap->ds->ds_dir)->dd_head_dataset_obj,
2721 &ddpa->origin_snaps, tag);
2722 if (error != 0)
2723 goto out;
2724
2725 if (dsl_dir_phys(snap->ds->ds_dir)->dd_origin_obj != 0) {
2726 error = dsl_dataset_hold_obj(dp,
2727 dsl_dir_phys(snap->ds->ds_dir)->dd_origin_obj,
2728 tag, &ddpa->origin_origin);
2729 if (error != 0)
2730 goto out;
2731 }
2732 out:
2733 if (error != 0)
2734 promote_rele(ddpa, tag);
2735 return (error);
2736 }
2737
2738 static void
2739 promote_rele(dsl_dataset_promote_arg_t *ddpa, void *tag)
2740 {
2741 snaplist_destroy(&ddpa->shared_snaps, tag);
2742 snaplist_destroy(&ddpa->clone_snaps, tag);
2743 snaplist_destroy(&ddpa->origin_snaps, tag);
2744 if (ddpa->origin_origin != NULL)
2745 dsl_dataset_rele(ddpa->origin_origin, tag);
2746 dsl_dataset_rele(ddpa->ddpa_clone, tag);
2747 }
2748
2749 /*
2750 * Promote a clone.
2751 *
2752 * If it fails due to a conflicting snapshot name, "conflsnap" will be filled
2753 * in with the name. (It must be at least MAXNAMELEN bytes long.)
2754 */
2755 int
2756 dsl_dataset_promote(const char *name, char *conflsnap)
2757 {
2758 dsl_dataset_promote_arg_t ddpa = { 0 };
2759 uint64_t numsnaps;
2760 int error;
2761 objset_t *os;
2762
2763 /*
2764 * We will modify space proportional to the number of
2765 * snapshots. Compute numsnaps.
2766 */
2767 error = dmu_objset_hold(name, FTAG, &os);
2768 if (error != 0)
2769 return (error);
2770 error = zap_count(dmu_objset_pool(os)->dp_meta_objset,
2771 dsl_dataset_phys(dmu_objset_ds(os))->ds_snapnames_zapobj,
2772 &numsnaps);
2773 dmu_objset_rele(os, FTAG);
2774 if (error != 0)
2775 return (error);
2776
2777 ddpa.ddpa_clonename = name;
2778 ddpa.err_ds = conflsnap;
2779 ddpa.cr = CRED();
2780
2781 return (dsl_sync_task(name, dsl_dataset_promote_check,
2782 dsl_dataset_promote_sync, &ddpa,
2783 2 + numsnaps, ZFS_SPACE_CHECK_RESERVED));
2784 }
2785
2786 int
2787 dsl_dataset_clone_swap_check_impl(dsl_dataset_t *clone,
2788 dsl_dataset_t *origin_head, boolean_t force, void *owner, dmu_tx_t *tx)
2789 {
2790 int64_t unused_refres_delta;
2791
2792 /* they should both be heads */
2793 if (clone->ds_is_snapshot ||
2794 origin_head->ds_is_snapshot)
2795 return (SET_ERROR(EINVAL));
2796
2797 /* if we are not forcing, the branch point should be just before them */
2798 if (!force && clone->ds_prev != origin_head->ds_prev)
2799 return (SET_ERROR(EINVAL));
2800
2801 /* clone should be the clone (unless they are unrelated) */
2802 if (clone->ds_prev != NULL &&
2803 clone->ds_prev != clone->ds_dir->dd_pool->dp_origin_snap &&
2804 origin_head->ds_dir != clone->ds_prev->ds_dir)
2805 return (SET_ERROR(EINVAL));
2806
2807 /* the clone should be a child of the origin */
2808 if (clone->ds_dir->dd_parent != origin_head->ds_dir)
2809 return (SET_ERROR(EINVAL));
2810
2811 /* origin_head shouldn't be modified unless 'force' */
2812 if (!force &&
2813 dsl_dataset_modified_since_snap(origin_head, origin_head->ds_prev))
2814 return (SET_ERROR(ETXTBSY));
2815
2816 /* origin_head should have no long holds (e.g. is not mounted) */
2817 if (dsl_dataset_handoff_check(origin_head, owner, tx))
2818 return (SET_ERROR(EBUSY));
2819
2820 /* check amount of any unconsumed refreservation */
2821 unused_refres_delta =
2822 (int64_t)MIN(origin_head->ds_reserved,
2823 dsl_dataset_phys(origin_head)->ds_unique_bytes) -
2824 (int64_t)MIN(origin_head->ds_reserved,
2825 dsl_dataset_phys(clone)->ds_unique_bytes);
2826
2827 if (unused_refres_delta > 0 &&
2828 unused_refres_delta >
2829 dsl_dir_space_available(origin_head->ds_dir, NULL, 0, TRUE))
2830 return (SET_ERROR(ENOSPC));
2831
2832 /* clone can't be over the head's refquota */
2833 if (origin_head->ds_quota != 0 &&
2834 dsl_dataset_phys(clone)->ds_referenced_bytes >
2835 origin_head->ds_quota)
2836 return (SET_ERROR(EDQUOT));
2837
2838 return (0);
2839 }
2840
2841 void
2842 dsl_dataset_clone_swap_sync_impl(dsl_dataset_t *clone,
2843 dsl_dataset_t *origin_head, dmu_tx_t *tx)
2844 {
2845 dsl_pool_t *dp = dmu_tx_pool(tx);
2846 int64_t unused_refres_delta;
2847
2848 ASSERT(clone->ds_reserved == 0);
2849 ASSERT(origin_head->ds_quota == 0 ||
2850 dsl_dataset_phys(clone)->ds_unique_bytes <= origin_head->ds_quota);
2851 ASSERT3P(clone->ds_prev, ==, origin_head->ds_prev);
2852
2853 /*
2854 * Swap per-dataset feature flags.
2855 */
2856 for (spa_feature_t f = 0; f < SPA_FEATURES; f++) {
2857 if (!(spa_feature_table[f].fi_flags &
2858 ZFEATURE_FLAG_PER_DATASET)) {
2859 ASSERT(!clone->ds_feature_inuse[f]);
2860 ASSERT(!origin_head->ds_feature_inuse[f]);
2861 continue;
2862 }
2863
2864 boolean_t clone_inuse = clone->ds_feature_inuse[f];
2865 boolean_t origin_head_inuse = origin_head->ds_feature_inuse[f];
2866
2867 if (clone_inuse) {
2868 dsl_dataset_deactivate_feature(clone->ds_object, f, tx);
2869 clone->ds_feature_inuse[f] = B_FALSE;
2870 }
2871 if (origin_head_inuse) {
2872 dsl_dataset_deactivate_feature(origin_head->ds_object,
2873 f, tx);
2874 origin_head->ds_feature_inuse[f] = B_FALSE;
2875 }
2876 if (clone_inuse) {
2877 dsl_dataset_activate_feature(origin_head->ds_object,
2878 f, tx);
2879 origin_head->ds_feature_inuse[f] = B_TRUE;
2880 }
2881 if (origin_head_inuse) {
2882 dsl_dataset_activate_feature(clone->ds_object, f, tx);
2883 clone->ds_feature_inuse[f] = B_TRUE;
2884 }
2885 }
2886
2887 dmu_buf_will_dirty(clone->ds_dbuf, tx);
2888 dmu_buf_will_dirty(origin_head->ds_dbuf, tx);
2889
2890 if (clone->ds_objset != NULL) {
2891 dmu_objset_evict(clone->ds_objset);
2892 clone->ds_objset = NULL;
2893 }
2894
2895 if (origin_head->ds_objset != NULL) {
2896 dmu_objset_evict(origin_head->ds_objset);
2897 origin_head->ds_objset = NULL;
2898 }
2899
2900 unused_refres_delta =
2901 (int64_t)MIN(origin_head->ds_reserved,
2902 dsl_dataset_phys(origin_head)->ds_unique_bytes) -
2903 (int64_t)MIN(origin_head->ds_reserved,
2904 dsl_dataset_phys(clone)->ds_unique_bytes);
2905
2906 /*
2907 * Reset origin's unique bytes, if it exists.
2908 */
2909 if (clone->ds_prev) {
2910 dsl_dataset_t *origin = clone->ds_prev;
2911 uint64_t comp, uncomp;
2912
2913 dmu_buf_will_dirty(origin->ds_dbuf, tx);
2914 dsl_deadlist_space_range(&clone->ds_deadlist,
2915 dsl_dataset_phys(origin)->ds_prev_snap_txg, UINT64_MAX,
2916 &dsl_dataset_phys(origin)->ds_unique_bytes, &comp, &uncomp);
2917 }
2918
2919 /* swap blkptrs */
2920 {
2921 blkptr_t tmp;
2922 tmp = dsl_dataset_phys(origin_head)->ds_bp;
2923 dsl_dataset_phys(origin_head)->ds_bp =
2924 dsl_dataset_phys(clone)->ds_bp;
2925 dsl_dataset_phys(clone)->ds_bp = tmp;
2926 }
2927
2928 /* set dd_*_bytes */
2929 {
2930 int64_t dused, dcomp, duncomp;
2931 uint64_t cdl_used, cdl_comp, cdl_uncomp;
2932 uint64_t odl_used, odl_comp, odl_uncomp;
2933
2934 ASSERT3U(dsl_dir_phys(clone->ds_dir)->
2935 dd_used_breakdown[DD_USED_SNAP], ==, 0);
2936
2937 dsl_deadlist_space(&clone->ds_deadlist,
2938 &cdl_used, &cdl_comp, &cdl_uncomp);
2939 dsl_deadlist_space(&origin_head->ds_deadlist,
2940 &odl_used, &odl_comp, &odl_uncomp);
2941
2942 dused = dsl_dataset_phys(clone)->ds_referenced_bytes +
2943 cdl_used -
2944 (dsl_dataset_phys(origin_head)->ds_referenced_bytes +
2945 odl_used);
2946 dcomp = dsl_dataset_phys(clone)->ds_compressed_bytes +
2947 cdl_comp -
2948 (dsl_dataset_phys(origin_head)->ds_compressed_bytes +
2949 odl_comp);
2950 duncomp = dsl_dataset_phys(clone)->ds_uncompressed_bytes +
2951 cdl_uncomp -
2952 (dsl_dataset_phys(origin_head)->ds_uncompressed_bytes +
2953 odl_uncomp);
2954
2955 dsl_dir_diduse_space(origin_head->ds_dir, DD_USED_HEAD,
2956 dused, dcomp, duncomp, tx);
2957 dsl_dir_diduse_space(clone->ds_dir, DD_USED_HEAD,
2958 -dused, -dcomp, -duncomp, tx);
2959
2960 /*
2961 * The difference in the space used by snapshots is the
2962 * difference in snapshot space due to the head's
2963 * deadlist (since that's the only thing that's
2964 * changing that affects the snapused).
2965 */
2966 dsl_deadlist_space_range(&clone->ds_deadlist,
2967 origin_head->ds_dir->dd_origin_txg, UINT64_MAX,
2968 &cdl_used, &cdl_comp, &cdl_uncomp);
2969 dsl_deadlist_space_range(&origin_head->ds_deadlist,
2970 origin_head->ds_dir->dd_origin_txg, UINT64_MAX,
2971 &odl_used, &odl_comp, &odl_uncomp);
2972 dsl_dir_transfer_space(origin_head->ds_dir, cdl_used - odl_used,
2973 DD_USED_HEAD, DD_USED_SNAP, tx);
2974 }
2975
2976 /* swap ds_*_bytes */
2977 SWITCH64(dsl_dataset_phys(origin_head)->ds_referenced_bytes,
2978 dsl_dataset_phys(clone)->ds_referenced_bytes);
2979 SWITCH64(dsl_dataset_phys(origin_head)->ds_compressed_bytes,
2980 dsl_dataset_phys(clone)->ds_compressed_bytes);
2981 SWITCH64(dsl_dataset_phys(origin_head)->ds_uncompressed_bytes,
2982 dsl_dataset_phys(clone)->ds_uncompressed_bytes);
2983 SWITCH64(dsl_dataset_phys(origin_head)->ds_unique_bytes,
2984 dsl_dataset_phys(clone)->ds_unique_bytes);
2985
2986 /* apply any parent delta for change in unconsumed refreservation */
2987 dsl_dir_diduse_space(origin_head->ds_dir, DD_USED_REFRSRV,
2988 unused_refres_delta, 0, 0, tx);
2989
2990 /*
2991 * Swap deadlists.
2992 */
2993 dsl_deadlist_close(&clone->ds_deadlist);
2994 dsl_deadlist_close(&origin_head->ds_deadlist);
2995 SWITCH64(dsl_dataset_phys(origin_head)->ds_deadlist_obj,
2996 dsl_dataset_phys(clone)->ds_deadlist_obj);
2997 dsl_deadlist_open(&clone->ds_deadlist, dp->dp_meta_objset,
2998 dsl_dataset_phys(clone)->ds_deadlist_obj);
2999 dsl_deadlist_open(&origin_head->ds_deadlist, dp->dp_meta_objset,
3000 dsl_dataset_phys(origin_head)->ds_deadlist_obj);
3001
3002 dsl_scan_ds_clone_swapped(origin_head, clone, tx);
3003
3004 spa_history_log_internal_ds(clone, "clone swap", tx,
3005 "parent=%s", origin_head->ds_dir->dd_myname);
3006 }
3007
3008 /*
3009 * Given a pool name and a dataset object number in that pool,
3010 * return the name of that dataset.
3011 */
3012 int
3013 dsl_dsobj_to_dsname(char *pname, uint64_t obj, char *buf)
3014 {
3015 dsl_pool_t *dp;
3016 dsl_dataset_t *ds;
3017 int error;
3018
3019 error = dsl_pool_hold(pname, FTAG, &dp);
3020 if (error != 0)
3021 return (error);
3022
3023 error = dsl_dataset_hold_obj(dp, obj, FTAG, &ds);
3024 if (error == 0) {
3025 dsl_dataset_name(ds, buf);
3026 dsl_dataset_rele(ds, FTAG);
3027 }
3028 dsl_pool_rele(dp, FTAG);
3029
3030 return (error);
3031 }
3032
3033 int
3034 dsl_dataset_check_quota(dsl_dataset_t *ds, boolean_t check_quota,
3035 uint64_t asize, uint64_t inflight, uint64_t *used, uint64_t *ref_rsrv)
3036 {
3037 int error = 0;
3038
3039 ASSERT3S(asize, >, 0);
3040
3041 /*
3042 * *ref_rsrv is the portion of asize that will come from any
3043 * unconsumed refreservation space.
3044 */
3045 *ref_rsrv = 0;
3046
3047 mutex_enter(&ds->ds_lock);
3048 /*
3049 * Make a space adjustment for reserved bytes.
3050 */
3051 if (ds->ds_reserved > dsl_dataset_phys(ds)->ds_unique_bytes) {
3052 ASSERT3U(*used, >=,
3053 ds->ds_reserved - dsl_dataset_phys(ds)->ds_unique_bytes);
3054 *used -=
3055 (ds->ds_reserved - dsl_dataset_phys(ds)->ds_unique_bytes);
3056 *ref_rsrv =
3057 asize - MIN(asize, parent_delta(ds, asize + inflight));
3058 }
3059
3060 if (!check_quota || ds->ds_quota == 0) {
3061 mutex_exit(&ds->ds_lock);
3062 return (0);
3063 }
3064 /*
3065 * If they are requesting more space, and our current estimate
3066 * is over quota, they get to try again unless the actual
3067 * on-disk is over quota and there are no pending changes (which
3068 * may free up space for us).
3069 */
3070 if (dsl_dataset_phys(ds)->ds_referenced_bytes + inflight >=
3071 ds->ds_quota) {
3072 if (inflight > 0 ||
3073 dsl_dataset_phys(ds)->ds_referenced_bytes < ds->ds_quota)
3074 error = SET_ERROR(ERESTART);
3075 else
3076 error = SET_ERROR(EDQUOT);
3077 }
3078 mutex_exit(&ds->ds_lock);
3079
3080 return (error);
3081 }
3082
3083 typedef struct dsl_dataset_set_qr_arg {
3084 const char *ddsqra_name;
3085 zprop_source_t ddsqra_source;
3086 uint64_t ddsqra_value;
3087 } dsl_dataset_set_qr_arg_t;
3088
3089
3090 /* ARGSUSED */
3091 static int
3092 dsl_dataset_set_refquota_check(void *arg, dmu_tx_t *tx)
3093 {
3094 dsl_dataset_set_qr_arg_t *ddsqra = arg;
3095 dsl_pool_t *dp = dmu_tx_pool(tx);
3096 dsl_dataset_t *ds;
3097 int error;
3098 uint64_t newval;
3099
3100 if (spa_version(dp->dp_spa) < SPA_VERSION_REFQUOTA)
3101 return (SET_ERROR(ENOTSUP));
3102
3103 error = dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds);
3104 if (error != 0)
3105 return (error);
3106
3107 if (ds->ds_is_snapshot) {
3108 dsl_dataset_rele(ds, FTAG);
3109 return (SET_ERROR(EINVAL));
3110 }
3111
3112 error = dsl_prop_predict(ds->ds_dir,
3113 zfs_prop_to_name(ZFS_PROP_REFQUOTA),
3114 ddsqra->ddsqra_source, ddsqra->ddsqra_value, &newval);
3115 if (error != 0) {
3116 dsl_dataset_rele(ds, FTAG);
3117 return (error);
3118 }
3119
3120 if (newval == 0) {
3121 dsl_dataset_rele(ds, FTAG);
3122 return (0);
3123 }
3124
3125 if (newval < dsl_dataset_phys(ds)->ds_referenced_bytes ||
3126 newval < ds->ds_reserved) {
3127 dsl_dataset_rele(ds, FTAG);
3128 return (SET_ERROR(ENOSPC));
3129 }
3130
3131 dsl_dataset_rele(ds, FTAG);
3132 return (0);
3133 }
3134
3135 static void
3136 dsl_dataset_set_refquota_sync(void *arg, dmu_tx_t *tx)
3137 {
3138 dsl_dataset_set_qr_arg_t *ddsqra = arg;
3139 dsl_pool_t *dp = dmu_tx_pool(tx);
3140 dsl_dataset_t *ds;
3141 uint64_t newval;
3142
3143 VERIFY0(dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds));
3144
3145 dsl_prop_set_sync_impl(ds,
3146 zfs_prop_to_name(ZFS_PROP_REFQUOTA),
3147 ddsqra->ddsqra_source, sizeof (ddsqra->ddsqra_value), 1,
3148 &ddsqra->ddsqra_value, tx);
3149
3150 VERIFY0(dsl_prop_get_int_ds(ds,
3151 zfs_prop_to_name(ZFS_PROP_REFQUOTA), &newval));
3152
3153 if (ds->ds_quota != newval) {
3154 dmu_buf_will_dirty(ds->ds_dbuf, tx);
3155 ds->ds_quota = newval;
3156 }
3157 dsl_dataset_rele(ds, FTAG);
3158 }
3159
3160 int
3161 dsl_dataset_set_refquota(const char *dsname, zprop_source_t source,
3162 uint64_t refquota)
3163 {
3164 dsl_dataset_set_qr_arg_t ddsqra;
3165
3166 ddsqra.ddsqra_name = dsname;
3167 ddsqra.ddsqra_source = source;
3168 ddsqra.ddsqra_value = refquota;
3169
3170 return (dsl_sync_task(dsname, dsl_dataset_set_refquota_check,
3171 dsl_dataset_set_refquota_sync, &ddsqra, 0, ZFS_SPACE_CHECK_NONE));
3172 }
3173
3174 static int
3175 dsl_dataset_set_refreservation_check(void *arg, dmu_tx_t *tx)
3176 {
3177 dsl_dataset_set_qr_arg_t *ddsqra = arg;
3178 dsl_pool_t *dp = dmu_tx_pool(tx);
3179 dsl_dataset_t *ds;
3180 int error;
3181 uint64_t newval, unique;
3182
3183 if (spa_version(dp->dp_spa) < SPA_VERSION_REFRESERVATION)
3184 return (SET_ERROR(ENOTSUP));
3185
3186 error = dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds);
3187 if (error != 0)
3188 return (error);
3189
3190 if (ds->ds_is_snapshot) {
3191 dsl_dataset_rele(ds, FTAG);
3192 return (SET_ERROR(EINVAL));
3193 }
3194
3195 error = dsl_prop_predict(ds->ds_dir,
3196 zfs_prop_to_name(ZFS_PROP_REFRESERVATION),
3197 ddsqra->ddsqra_source, ddsqra->ddsqra_value, &newval);
3198 if (error != 0) {
3199 dsl_dataset_rele(ds, FTAG);
3200 return (error);
3201 }
3202
3203 /*
3204 * If we are doing the preliminary check in open context, the
3205 * space estimates may be inaccurate.
3206 */
3207 if (!dmu_tx_is_syncing(tx)) {
3208 dsl_dataset_rele(ds, FTAG);
3209 return (0);
3210 }
3211
3212 mutex_enter(&ds->ds_lock);
3213 if (!DS_UNIQUE_IS_ACCURATE(ds))
3214 dsl_dataset_recalc_head_uniq(ds);
3215 unique = dsl_dataset_phys(ds)->ds_unique_bytes;
3216 mutex_exit(&ds->ds_lock);
3217
3218 if (MAX(unique, newval) > MAX(unique, ds->ds_reserved)) {
3219 uint64_t delta = MAX(unique, newval) -
3220 MAX(unique, ds->ds_reserved);
3221
3222 if (delta >
3223 dsl_dir_space_available(ds->ds_dir, NULL, 0, B_TRUE) ||
3224 (ds->ds_quota > 0 && newval > ds->ds_quota)) {
3225 dsl_dataset_rele(ds, FTAG);
3226 return (SET_ERROR(ENOSPC));
3227 }
3228 }
3229
3230 dsl_dataset_rele(ds, FTAG);
3231 return (0);
3232 }
3233
3234 void
3235 dsl_dataset_set_refreservation_sync_impl(dsl_dataset_t *ds,
3236 zprop_source_t source, uint64_t value, dmu_tx_t *tx)
3237 {
3238 uint64_t newval;
3239 uint64_t unique;
3240 int64_t delta;
3241
3242 dsl_prop_set_sync_impl(ds, zfs_prop_to_name(ZFS_PROP_REFRESERVATION),
3243 source, sizeof (value), 1, &value, tx);
3244
3245 VERIFY0(dsl_prop_get_int_ds(ds,
3246 zfs_prop_to_name(ZFS_PROP_REFRESERVATION), &newval));
3247
3248 dmu_buf_will_dirty(ds->ds_dbuf, tx);
3249 mutex_enter(&ds->ds_dir->dd_lock);
3250 mutex_enter(&ds->ds_lock);
3251 ASSERT(DS_UNIQUE_IS_ACCURATE(ds));
3252 unique = dsl_dataset_phys(ds)->ds_unique_bytes;
3253 delta = MAX(0, (int64_t)(newval - unique)) -
3254 MAX(0, (int64_t)(ds->ds_reserved - unique));
3255 ds->ds_reserved = newval;
3256 mutex_exit(&ds->ds_lock);
3257
3258 dsl_dir_diduse_space(ds->ds_dir, DD_USED_REFRSRV, delta, 0, 0, tx);
3259 mutex_exit(&ds->ds_dir->dd_lock);
3260 }
3261
3262 static void
3263 dsl_dataset_set_refreservation_sync(void *arg, dmu_tx_t *tx)
3264 {
3265 dsl_dataset_set_qr_arg_t *ddsqra = arg;
3266 dsl_pool_t *dp = dmu_tx_pool(tx);
3267 dsl_dataset_t *ds;
3268
3269 VERIFY0(dsl_dataset_hold(dp, ddsqra->ddsqra_name, FTAG, &ds));
3270 dsl_dataset_set_refreservation_sync_impl(ds,
3271 ddsqra->ddsqra_source, ddsqra->ddsqra_value, tx);
3272 dsl_dataset_rele(ds, FTAG);
3273 }
3274
3275 int
3276 dsl_dataset_set_refreservation(const char *dsname, zprop_source_t source,
3277 uint64_t refreservation)
3278 {
3279 dsl_dataset_set_qr_arg_t ddsqra;
3280
3281 ddsqra.ddsqra_name = dsname;
3282 ddsqra.ddsqra_source = source;
3283 ddsqra.ddsqra_value = refreservation;
3284
3285 return (dsl_sync_task(dsname, dsl_dataset_set_refreservation_check,
3286 dsl_dataset_set_refreservation_sync, &ddsqra,
3287 0, ZFS_SPACE_CHECK_NONE));
3288 }
3289
3290 /*
3291 * Return (in *usedp) the amount of space written in new that is not
3292 * present in oldsnap. New may be a snapshot or the head. Old must be
3293 * a snapshot before new, in new's filesystem (or its origin). If not then
3294 * fail and return EINVAL.
3295 *
3296 * The written space is calculated by considering two components: First, we
3297 * ignore any freed space, and calculate the written as new's used space
3298 * minus old's used space. Next, we add in the amount of space that was freed
3299 * between the two snapshots, thus reducing new's used space relative to old's.
3300 * Specifically, this is the space that was born before old->ds_creation_txg,
3301 * and freed before new (ie. on new's deadlist or a previous deadlist).
3302 *
3303 * space freed [---------------------]
3304 * snapshots ---O-------O--------O-------O------
3305 * oldsnap new
3306 */
3307 int
3308 dsl_dataset_space_written(dsl_dataset_t *oldsnap, dsl_dataset_t *new,
3309 uint64_t *usedp, uint64_t *compp, uint64_t *uncompp)
3310 {
3311 int err = 0;
3312 uint64_t snapobj;
3313 dsl_pool_t *dp = new->ds_dir->dd_pool;
3314
3315 ASSERT(dsl_pool_config_held(dp));
3316
3317 *usedp = 0;
3318 *usedp += dsl_dataset_phys(new)->ds_referenced_bytes;
3319 *usedp -= dsl_dataset_phys(oldsnap)->ds_referenced_bytes;
3320
3321 *compp = 0;
3322 *compp += dsl_dataset_phys(new)->ds_compressed_bytes;
3323 *compp -= dsl_dataset_phys(oldsnap)->ds_compressed_bytes;
3324
3325 *uncompp = 0;
3326 *uncompp += dsl_dataset_phys(new)->ds_uncompressed_bytes;
3327 *uncompp -= dsl_dataset_phys(oldsnap)->ds_uncompressed_bytes;
3328
3329 snapobj = new->ds_object;
3330 while (snapobj != oldsnap->ds_object) {
3331 dsl_dataset_t *snap;
3332 uint64_t used, comp, uncomp;
3333
3334 if (snapobj == new->ds_object) {
3335 snap = new;
3336 } else {
3337 err = dsl_dataset_hold_obj(dp, snapobj, FTAG, &snap);
3338 if (err != 0)
3339 break;
3340 }
3341
3342 if (dsl_dataset_phys(snap)->ds_prev_snap_txg ==
3343 dsl_dataset_phys(oldsnap)->ds_creation_txg) {
3344 /*
3345 * The blocks in the deadlist can not be born after
3346 * ds_prev_snap_txg, so get the whole deadlist space,
3347 * which is more efficient (especially for old-format
3348 * deadlists). Unfortunately the deadlist code
3349 * doesn't have enough information to make this
3350 * optimization itself.
3351 */
3352 dsl_deadlist_space(&snap->ds_deadlist,
3353 &used, &comp, &uncomp);
3354 } else {
3355 dsl_deadlist_space_range(&snap->ds_deadlist,
3356 0, dsl_dataset_phys(oldsnap)->ds_creation_txg,
3357 &used, &comp, &uncomp);
3358 }
3359 *usedp += used;
3360 *compp += comp;
3361 *uncompp += uncomp;
3362
3363 /*
3364 * If we get to the beginning of the chain of snapshots
3365 * (ds_prev_snap_obj == 0) before oldsnap, then oldsnap
3366 * was not a snapshot of/before new.
3367 */
3368 snapobj = dsl_dataset_phys(snap)->ds_prev_snap_obj;
3369 if (snap != new)
3370 dsl_dataset_rele(snap, FTAG);
3371 if (snapobj == 0) {
3372 err = SET_ERROR(EINVAL);
3373 break;
3374 }
3375
3376 }
3377 return (err);
3378 }
3379
3380 /*
3381 * Return (in *usedp) the amount of space that will be reclaimed if firstsnap,
3382 * lastsnap, and all snapshots in between are deleted.
3383 *
3384 * blocks that would be freed [---------------------------]
3385 * snapshots ---O-------O--------O-------O--------O
3386 * firstsnap lastsnap
3387 *
3388 * This is the set of blocks that were born after the snap before firstsnap,
3389 * (birth > firstsnap->prev_snap_txg) and died before the snap after the
3390 * last snap (ie, is on lastsnap->ds_next->ds_deadlist or an earlier deadlist).
3391 * We calculate this by iterating over the relevant deadlists (from the snap
3392 * after lastsnap, backward to the snap after firstsnap), summing up the
3393 * space on the deadlist that was born after the snap before firstsnap.
3394 */
3395 int
3396 dsl_dataset_space_wouldfree(dsl_dataset_t *firstsnap,
3397 dsl_dataset_t *lastsnap,
3398 uint64_t *usedp, uint64_t *compp, uint64_t *uncompp)
3399 {
3400 int err = 0;
3401 uint64_t snapobj;
3402 dsl_pool_t *dp = firstsnap->ds_dir->dd_pool;
3403
3404 ASSERT(firstsnap->ds_is_snapshot);
3405 ASSERT(lastsnap->ds_is_snapshot);
3406
3407 /*
3408 * Check that the snapshots are in the same dsl_dir, and firstsnap
3409 * is before lastsnap.
3410 */
3411 if (firstsnap->ds_dir != lastsnap->ds_dir ||
3412 dsl_dataset_phys(firstsnap)->ds_creation_txg >
3413 dsl_dataset_phys(lastsnap)->ds_creation_txg)
3414 return (SET_ERROR(EINVAL));
3415
3416 *usedp = *compp = *uncompp = 0;
3417
3418 snapobj = dsl_dataset_phys(lastsnap)->ds_next_snap_obj;
3419 while (snapobj != firstsnap->ds_object) {
3420 dsl_dataset_t *ds;
3421 uint64_t used, comp, uncomp;
3422
3423 err = dsl_dataset_hold_obj(dp, snapobj, FTAG, &ds);
3424 if (err != 0)
3425 break;
3426
3427 dsl_deadlist_space_range(&ds->ds_deadlist,
3428 dsl_dataset_phys(firstsnap)->ds_prev_snap_txg, UINT64_MAX,
3429 &used, &comp, &uncomp);
3430 *usedp += used;
3431 *compp += comp;
3432 *uncompp += uncomp;
3433
3434 snapobj = dsl_dataset_phys(ds)->ds_prev_snap_obj;
3435 ASSERT3U(snapobj, !=, 0);
3436 dsl_dataset_rele(ds, FTAG);
3437 }
3438 return (err);
3439 }
3440
3441 /*
3442 * Return TRUE if 'earlier' is an earlier snapshot in 'later's timeline.
3443 * For example, they could both be snapshots of the same filesystem, and
3444 * 'earlier' is before 'later'. Or 'earlier' could be the origin of
3445 * 'later's filesystem. Or 'earlier' could be an older snapshot in the origin's
3446 * filesystem. Or 'earlier' could be the origin's origin.
3447 *
3448 * If non-zero, earlier_txg is used instead of earlier's ds_creation_txg.
3449 */
3450 boolean_t
3451 dsl_dataset_is_before(dsl_dataset_t *later, dsl_dataset_t *earlier,
3452 uint64_t earlier_txg)
3453 {
3454 dsl_pool_t *dp = later->ds_dir->dd_pool;
3455 int error;
3456 boolean_t ret;
3457
3458 ASSERT(dsl_pool_config_held(dp));
3459 ASSERT(earlier->ds_is_snapshot || earlier_txg != 0);
3460
3461 if (earlier_txg == 0)
3462 earlier_txg = dsl_dataset_phys(earlier)->ds_creation_txg;
3463
3464 if (later->ds_is_snapshot &&
3465 earlier_txg >= dsl_dataset_phys(later)->ds_creation_txg)
3466 return (B_FALSE);
3467
3468 if (later->ds_dir == earlier->ds_dir)
3469 return (B_TRUE);
3470 if (!dsl_dir_is_clone(later->ds_dir))
3471 return (B_FALSE);
3472
3473 if (dsl_dir_phys(later->ds_dir)->dd_origin_obj == earlier->ds_object)
3474 return (B_TRUE);
3475 dsl_dataset_t *origin;
3476 error = dsl_dataset_hold_obj(dp,
3477 dsl_dir_phys(later->ds_dir)->dd_origin_obj, FTAG, &origin);
3478 if (error != 0)
3479 return (B_FALSE);
3480 ret = dsl_dataset_is_before(origin, earlier, earlier_txg);
3481 dsl_dataset_rele(origin, FTAG);
3482 return (ret);
3483 }
3484
3485 void
3486 dsl_dataset_zapify(dsl_dataset_t *ds, dmu_tx_t *tx)
3487 {
3488 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
3489 dmu_object_zapify(mos, ds->ds_object, DMU_OT_DSL_DATASET, tx);
3490 }
3491
3492 boolean_t
3493 dsl_dataset_is_zapified(dsl_dataset_t *ds)
3494 {
3495 dmu_object_info_t doi;
3496
3497 dmu_object_info_from_db(ds->ds_dbuf, &doi);
3498 return (doi.doi_type == DMU_OTN_ZAP_METADATA);
3499 }
3500
3501 boolean_t
3502 dsl_dataset_has_resume_receive_state(dsl_dataset_t *ds)
3503 {
3504 return (dsl_dataset_is_zapified(ds) &&
3505 zap_contains(ds->ds_dir->dd_pool->dp_meta_objset,
3506 ds->ds_object, DS_FIELD_RESUME_TOGUID) == 0);
3507 }