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