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34dc7c2f
BB		 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/*
428870ff 22 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
34dc7c2f
BB		 23 */
24
34dc7c2f
BB		 25#include <sys/dmu_objset.h>
26#include <sys/dsl_dataset.h>
27#include <sys/dsl_dir.h>
28#include <sys/dsl_prop.h>
29#include <sys/dsl_synctask.h>
30#include <sys/dmu_traverse.h>
31#include <sys/dmu_tx.h>
32#include <sys/arc.h>
33#include <sys/zio.h>
34#include <sys/zap.h>
35#include <sys/unique.h>
36#include <sys/zfs_context.h>
37#include <sys/zfs_ioctl.h>
38#include <sys/spa.h>
b128c09f 39#include <sys/zfs_znode.h>
572e2857 40#include <sys/zfs_onexit.h>
45d1cae3 41#include <sys/zvol.h>
428870ff
BB		 42#include <sys/dsl_scan.h>
43#include <sys/dsl_deadlist.h>
44
b128c09f
BB		 45static char *dsl_reaper = "the grim reaper";
46
34dc7c2f
BB		 47static dsl_checkfunc_t dsl_dataset_destroy_begin_check;
48static dsl_syncfunc_t dsl_dataset_destroy_begin_sync;
34dc7c2f
BB		 49static dsl_syncfunc_t dsl_dataset_set_reservation_sync;
50
428870ff
BB		 51#define SWITCH64(x, y) \
52 { \
53 uint64_t __tmp = (x); \
54 (x) = (y); \
55 (y) = __tmp; \
56 }
57
34dc7c2f
BB		 58#define DS_REF_MAX (1ULL << 62)
59
60#define DSL_DEADLIST_BLOCKSIZE SPA_MAXBLOCKSIZE
61
b128c09f
BB		 62#define DSL_DATASET_IS_DESTROYED(ds) ((ds)->ds_owner == dsl_reaper)
63
34dc7c2f
BB		 64
65/*
66 * Figure out how much of this delta should be propogated to the dsl_dir
67 * layer. If there's a refreservation, that space has already been
68 * partially accounted for in our ancestors.
69 */
70static int64_t
71parent_delta(dsl_dataset_t *ds, int64_t delta)
72{
73 uint64_t old_bytes, new_bytes;
74
75 if (ds->ds_reserved == 0)
76 return (delta);
77
78 old_bytes = MAX(ds->ds_phys->ds_unique_bytes, ds->ds_reserved);
79 new_bytes = MAX(ds->ds_phys->ds_unique_bytes + delta, ds->ds_reserved);
80
81 ASSERT3U(ABS((int64_t)(new_bytes - old_bytes)), <=, ABS(delta));
82 return (new_bytes - old_bytes);
83}
84
85void
428870ff 86dsl_dataset_block_born(dsl_dataset_t *ds, const blkptr_t *bp, dmu_tx_t *tx)
34dc7c2f 87{
428870ff 88 int used = bp_get_dsize_sync(tx->tx_pool->dp_spa, bp);
34dc7c2f
BB		 89 int compressed = BP_GET_PSIZE(bp);
90 int uncompressed = BP_GET_UCSIZE(bp);
91 int64_t delta;
92
428870ff 93 dprintf_bp(bp, "ds=%p", ds);
34dc7c2f
BB		 94
95 ASSERT(dmu_tx_is_syncing(tx));
96 /* It could have been compressed away to nothing */
97 if (BP_IS_HOLE(bp))
98 return;
99 ASSERT(BP_GET_TYPE(bp) != DMU_OT_NONE);
100 ASSERT3U(BP_GET_TYPE(bp), <, DMU_OT_NUMTYPES);
101 if (ds == NULL) {
102 /*
103 * Account for the meta-objset space in its placeholder
104 * dsl_dir.
105 */
106 ASSERT3U(compressed, ==, uncompressed); /* it's all metadata */
b128c09f 107 dsl_dir_diduse_space(tx->tx_pool->dp_mos_dir, DD_USED_HEAD,
34dc7c2f
BB		 108 used, compressed, uncompressed, tx);
109 dsl_dir_dirty(tx->tx_pool->dp_mos_dir, tx);
110 return;
111 }
112 dmu_buf_will_dirty(ds->ds_dbuf, tx);
428870ff 113
b128c09f 114 mutex_enter(&ds->ds_dir->dd_lock);
34dc7c2f
BB		 115 mutex_enter(&ds->ds_lock);
116 delta = parent_delta(ds, used);
117 ds->ds_phys->ds_used_bytes += used;
118 ds->ds_phys->ds_compressed_bytes += compressed;
119 ds->ds_phys->ds_uncompressed_bytes += uncompressed;
120 ds->ds_phys->ds_unique_bytes += used;
121 mutex_exit(&ds->ds_lock);
b128c09f
BB		 122 dsl_dir_diduse_space(ds->ds_dir, DD_USED_HEAD, delta,
123 compressed, uncompressed, tx);
124 dsl_dir_transfer_space(ds->ds_dir, used - delta,
125 DD_USED_REFRSRV, DD_USED_HEAD, tx);
126 mutex_exit(&ds->ds_dir->dd_lock);
34dc7c2f
BB		 127}
128
b128c09f 129int
428870ff
BB		 130dsl_dataset_block_kill(dsl_dataset_t *ds, const blkptr_t *bp, dmu_tx_t *tx,
131 boolean_t async)
34dc7c2f 132{
34dc7c2f 133 if (BP_IS_HOLE(bp))
b128c09f 134 return (0);
34dc7c2f 135
428870ff
BB		 136 ASSERT(dmu_tx_is_syncing(tx));
137 ASSERT(bp->blk_birth <= tx->tx_txg);
138
139 int used = bp_get_dsize_sync(tx->tx_pool->dp_spa, bp);
140 int compressed = BP_GET_PSIZE(bp);
141 int uncompressed = BP_GET_UCSIZE(bp);
142
34dc7c2f
BB		 143 ASSERT(used > 0);
144 if (ds == NULL) {
34dc7c2f
BB		 145 /*
146 * Account for the meta-objset space in its placeholder
147 * dataset.
148 */
428870ff 149 dsl_free(tx->tx_pool, tx->tx_txg, bp);
34dc7c2f 150
b128c09f 151 dsl_dir_diduse_space(tx->tx_pool->dp_mos_dir, DD_USED_HEAD,
34dc7c2f
BB		 152 -used, -compressed, -uncompressed, tx);
153 dsl_dir_dirty(tx->tx_pool->dp_mos_dir, tx);
b128c09f 154 return (used);
34dc7c2f
BB		 155 }
156 ASSERT3P(tx->tx_pool, ==, ds->ds_dir->dd_pool);
157
b128c09f 158 ASSERT(!dsl_dataset_is_snapshot(ds));
34dc7c2f
BB		 159 dmu_buf_will_dirty(ds->ds_dbuf, tx);
160
161 if (bp->blk_birth > ds->ds_phys->ds_prev_snap_txg) {
34dc7c2f
BB		 162 int64_t delta;
163
428870ff
BB		 164 dprintf_bp(bp, "freeing ds=%llu", ds->ds_object);
165 dsl_free(tx->tx_pool, tx->tx_txg, bp);
34dc7c2f 166
b128c09f 167 mutex_enter(&ds->ds_dir->dd_lock);
34dc7c2f
BB		 168 mutex_enter(&ds->ds_lock);
169 ASSERT(ds->ds_phys->ds_unique_bytes >= used ||
170 !DS_UNIQUE_IS_ACCURATE(ds));
171 delta = parent_delta(ds, -used);
172 ds->ds_phys->ds_unique_bytes -= used;
173 mutex_exit(&ds->ds_lock);
b128c09f 174 dsl_dir_diduse_space(ds->ds_dir, DD_USED_HEAD,
34dc7c2f 175 delta, -compressed, -uncompressed, tx);
b128c09f
BB		 176 dsl_dir_transfer_space(ds->ds_dir, -used - delta,
177 DD_USED_REFRSRV, DD_USED_HEAD, tx);
178 mutex_exit(&ds->ds_dir->dd_lock);
34dc7c2f
BB		 179 } else {
180 dprintf_bp(bp, "putting on dead list: %s", "");
428870ff
BB		 181 if (async) {
182 /*
183 * We are here as part of zio's write done callback,
184 * which means we're a zio interrupt thread. We can't
185 * call dsl_deadlist_insert() now because it may block
186 * waiting for I/O. Instead, put bp on the deferred
187 * queue and let dsl_pool_sync() finish the job.
188 */
189 bplist_append(&ds->ds_pending_deadlist, bp);
190 } else {
191 dsl_deadlist_insert(&ds->ds_deadlist, bp, tx);
192 }
34dc7c2f
BB		 193 ASSERT3U(ds->ds_prev->ds_object, ==,
194 ds->ds_phys->ds_prev_snap_obj);
195 ASSERT(ds->ds_prev->ds_phys->ds_num_children > 0);
196 /* if (bp->blk_birth > prev prev snap txg) prev unique += bs */
197 if (ds->ds_prev->ds_phys->ds_next_snap_obj ==
198 ds->ds_object && bp->blk_birth >
199 ds->ds_prev->ds_phys->ds_prev_snap_txg) {
200 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx);
201 mutex_enter(&ds->ds_prev->ds_lock);
202 ds->ds_prev->ds_phys->ds_unique_bytes += used;
203 mutex_exit(&ds->ds_prev->ds_lock);
204 }
428870ff 205 if (bp->blk_birth > ds->ds_dir->dd_origin_txg) {
b128c09f
BB		 206 dsl_dir_transfer_space(ds->ds_dir, used,
207 DD_USED_HEAD, DD_USED_SNAP, tx);
208 }
34dc7c2f
BB		 209 }
210 mutex_enter(&ds->ds_lock);
211 ASSERT3U(ds->ds_phys->ds_used_bytes, >=, used);
212 ds->ds_phys->ds_used_bytes -= used;
213 ASSERT3U(ds->ds_phys->ds_compressed_bytes, >=, compressed);
214 ds->ds_phys->ds_compressed_bytes -= compressed;
215 ASSERT3U(ds->ds_phys->ds_uncompressed_bytes, >=, uncompressed);
216 ds->ds_phys->ds_uncompressed_bytes -= uncompressed;
217 mutex_exit(&ds->ds_lock);
b128c09f
BB		 218
219 return (used);
34dc7c2f
BB		 220}
221
222uint64_t
223dsl_dataset_prev_snap_txg(dsl_dataset_t *ds)
224{
225 uint64_t trysnap = 0;
226
227 if (ds == NULL)
228 return (0);
229 /*
230 * The snapshot creation could fail, but that would cause an
231 * incorrect FALSE return, which would only result in an
232 * overestimation of the amount of space that an operation would
233 * consume, which is OK.
234 *
235 * There's also a small window where we could miss a pending
236 * snapshot, because we could set the sync task in the quiescing
237 * phase. So this should only be used as a guess.
238 */
239 if (ds->ds_trysnap_txg >
240 spa_last_synced_txg(ds->ds_dir->dd_pool->dp_spa))
241 trysnap = ds->ds_trysnap_txg;
242 return (MAX(ds->ds_phys->ds_prev_snap_txg, trysnap));
243}
244
9babb374 245boolean_t
428870ff
BB		 246dsl_dataset_block_freeable(dsl_dataset_t *ds, const blkptr_t *bp,
247 uint64_t blk_birth)
34dc7c2f 248{
428870ff
BB		 249 if (blk_birth <= dsl_dataset_prev_snap_txg(ds))
250 return (B_FALSE);
251
572e2857 252 ddt_prefetch(dsl_dataset_get_spa(ds), bp);
428870ff
BB		 253
254 return (B_TRUE);
34dc7c2f
BB		 255}
256
257/* ARGSUSED */
258static void
259dsl_dataset_evict(dmu_buf_t *db, void *dsv)
260{
261 dsl_dataset_t *ds = dsv;
262
b128c09f 263 ASSERT(ds->ds_owner == NULL || DSL_DATASET_IS_DESTROYED(ds));
34dc7c2f 264
34dc7c2f
BB		 265 unique_remove(ds->ds_fsid_guid);
266
428870ff
BB		 267 if (ds->ds_objset != NULL)
268 dmu_objset_evict(ds->ds_objset);
34dc7c2f
BB		 269
270 if (ds->ds_prev) {
b128c09f 271 dsl_dataset_drop_ref(ds->ds_prev, ds);
34dc7c2f
BB		 272 ds->ds_prev = NULL;
273 }
274
428870ff
BB		 275 bplist_destroy(&ds->ds_pending_deadlist);
276 if (db != NULL) {
277 dsl_deadlist_close(&ds->ds_deadlist);
278 } else {
279 ASSERT(ds->ds_deadlist.dl_dbuf == NULL);
280 ASSERT(!ds->ds_deadlist.dl_oldfmt);
281 }
b128c09f
BB		 282 if (ds->ds_dir)
283 dsl_dir_close(ds->ds_dir, ds);
34dc7c2f
BB		 284
285 ASSERT(!list_link_active(&ds->ds_synced_link));
286
287 mutex_destroy(&ds->ds_lock);
45d1cae3 288 mutex_destroy(&ds->ds_recvlock);
34dc7c2f 289 mutex_destroy(&ds->ds_opening_lock);
b128c09f
BB		 290 rw_destroy(&ds->ds_rwlock);
291 cv_destroy(&ds->ds_exclusive_cv);
34dc7c2f
BB		 292
293 kmem_free(ds, sizeof (dsl_dataset_t));
294}
295
296static int
297dsl_dataset_get_snapname(dsl_dataset_t *ds)
298{
299 dsl_dataset_phys_t *headphys;
300 int err;
301 dmu_buf_t *headdbuf;
302 dsl_pool_t *dp = ds->ds_dir->dd_pool;
303 objset_t *mos = dp->dp_meta_objset;
304
305 if (ds->ds_snapname[0])
306 return (0);
307 if (ds->ds_phys->ds_next_snap_obj == 0)
308 return (0);
309
310 err = dmu_bonus_hold(mos, ds->ds_dir->dd_phys->dd_head_dataset_obj,
311 FTAG, &headdbuf);
312 if (err)
313 return (err);
314 headphys = headdbuf->db_data;
315 err = zap_value_search(dp->dp_meta_objset,
316 headphys->ds_snapnames_zapobj, ds->ds_object, 0, ds->ds_snapname);
317 dmu_buf_rele(headdbuf, FTAG);
318 return (err);
319}
320
321static int
b128c09f 322dsl_dataset_snap_lookup(dsl_dataset_t *ds, const char *name, uint64_t *value)
34dc7c2f 323{
b128c09f
BB		 324 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
325 uint64_t snapobj = ds->ds_phys->ds_snapnames_zapobj;
34dc7c2f
BB		 326 matchtype_t mt;
327 int err;
328
b128c09f 329 if (ds->ds_phys->ds_flags & DS_FLAG_CI_DATASET)
34dc7c2f
BB		 330 mt = MT_FIRST;
331 else
332 mt = MT_EXACT;
333
b128c09f 334 err = zap_lookup_norm(mos, snapobj, name, 8, 1,
34dc7c2f
BB		 335 value, mt, NULL, 0, NULL);
336 if (err == ENOTSUP && mt == MT_FIRST)
b128c09f 337 err = zap_lookup(mos, snapobj, name, 8, 1, value);
34dc7c2f
BB		 338 return (err);
339}
340
341static int
b128c09f 342dsl_dataset_snap_remove(dsl_dataset_t *ds, char *name, dmu_tx_t *tx)
34dc7c2f 343{
b128c09f
BB		 344 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
345 uint64_t snapobj = ds->ds_phys->ds_snapnames_zapobj;
34dc7c2f
BB		 346 matchtype_t mt;
347 int err;
348
428870ff
BB		 349 dsl_dir_snap_cmtime_update(ds->ds_dir);
350
b128c09f 351 if (ds->ds_phys->ds_flags & DS_FLAG_CI_DATASET)
34dc7c2f
BB		 352 mt = MT_FIRST;
353 else
354 mt = MT_EXACT;
355
b128c09f 356 err = zap_remove_norm(mos, snapobj, name, mt, tx);
34dc7c2f 357 if (err == ENOTSUP && mt == MT_FIRST)
b128c09f 358 err = zap_remove(mos, snapobj, name, tx);
34dc7c2f
BB		 359 return (err);
360}
361
b128c09f
BB		 362static int
363dsl_dataset_get_ref(dsl_pool_t *dp, uint64_t dsobj, void *tag,
364 dsl_dataset_t **dsp)
34dc7c2f 365{
34dc7c2f
BB		 366 objset_t *mos = dp->dp_meta_objset;
367 dmu_buf_t *dbuf;
368 dsl_dataset_t *ds;
369 int err;
572e2857 370 dmu_object_info_t doi;
34dc7c2f
BB		 371
372 ASSERT(RW_LOCK_HELD(&dp->dp_config_rwlock) ||
373 dsl_pool_sync_context(dp));
374
375 err = dmu_bonus_hold(mos, dsobj, tag, &dbuf);
376 if (err)
377 return (err);
572e2857
BB		 378
379 /* Make sure dsobj has the correct object type. */
380 dmu_object_info_from_db(dbuf, &doi);
381 if (doi.doi_type != DMU_OT_DSL_DATASET)
382 return (EINVAL);
383
34dc7c2f
BB		 384 ds = dmu_buf_get_user(dbuf);
385 if (ds == NULL) {
386 dsl_dataset_t *winner;
387
388 ds = kmem_zalloc(sizeof (dsl_dataset_t), KM_SLEEP);
389 ds->ds_dbuf = dbuf;
390 ds->ds_object = dsobj;
391 ds->ds_phys = dbuf->db_data;
392
393 mutex_init(&ds->ds_lock, NULL, MUTEX_DEFAULT, NULL);
45d1cae3 394 mutex_init(&ds->ds_recvlock, NULL, MUTEX_DEFAULT, NULL);
34dc7c2f 395 mutex_init(&ds->ds_opening_lock, NULL, MUTEX_DEFAULT, NULL);
b128c09f
BB		 396 rw_init(&ds->ds_rwlock, 0, 0, 0);
397 cv_init(&ds->ds_exclusive_cv, NULL, CV_DEFAULT, NULL);
34dc7c2f 398
428870ff
BB		 399 bplist_create(&ds->ds_pending_deadlist);
400 dsl_deadlist_open(&ds->ds_deadlist,
34dc7c2f 401 mos, ds->ds_phys->ds_deadlist_obj);
428870ff 402
34dc7c2f
BB		 403 if (err == 0) {
404 err = dsl_dir_open_obj(dp,
405 ds->ds_phys->ds_dir_obj, NULL, ds, &ds->ds_dir);
406 }
407 if (err) {
34dc7c2f 408 mutex_destroy(&ds->ds_lock);
45d1cae3 409 mutex_destroy(&ds->ds_recvlock);
34dc7c2f 410 mutex_destroy(&ds->ds_opening_lock);
b128c09f
BB		 411 rw_destroy(&ds->ds_rwlock);
412 cv_destroy(&ds->ds_exclusive_cv);
428870ff
BB		 413 bplist_destroy(&ds->ds_pending_deadlist);
414 dsl_deadlist_close(&ds->ds_deadlist);
34dc7c2f
BB		 415 kmem_free(ds, sizeof (dsl_dataset_t));
416 dmu_buf_rele(dbuf, tag);
417 return (err);
418 }
419
b128c09f 420 if (!dsl_dataset_is_snapshot(ds)) {
34dc7c2f
BB		 421 ds->ds_snapname[0] = '\0';
422 if (ds->ds_phys->ds_prev_snap_obj) {
b128c09f
BB		 423 err = dsl_dataset_get_ref(dp,
424 ds->ds_phys->ds_prev_snap_obj,
425 ds, &ds->ds_prev);
34dc7c2f 426 }
45d1cae3
BB		 427 } else {
428 if (zfs_flags & ZFS_DEBUG_SNAPNAMES)
429 err = dsl_dataset_get_snapname(ds);
430 if (err == 0 && ds->ds_phys->ds_userrefs_obj != 0) {
431 err = zap_count(
432 ds->ds_dir->dd_pool->dp_meta_objset,
433 ds->ds_phys->ds_userrefs_obj,
434 &ds->ds_userrefs);
435 }
34dc7c2f
BB		 436 }
437
b128c09f 438 if (err == 0 && !dsl_dataset_is_snapshot(ds)) {
34dc7c2f
BB		 439 /*
440 * In sync context, we're called with either no lock
441 * or with the write lock. If we're not syncing,
442 * we're always called with the read lock held.
443 */
444 boolean_t need_lock =
445 !RW_WRITE_HELD(&dp->dp_config_rwlock) &&
446 dsl_pool_sync_context(dp);
447
448 if (need_lock)
449 rw_enter(&dp->dp_config_rwlock, RW_READER);
450
b128c09f 451 err = dsl_prop_get_ds(ds,
34dc7c2f
BB		 452 "refreservation", sizeof (uint64_t), 1,
453 &ds->ds_reserved, NULL);
454 if (err == 0) {
b128c09f 455 err = dsl_prop_get_ds(ds,
34dc7c2f
BB		 456 "refquota", sizeof (uint64_t), 1,
457 &ds->ds_quota, NULL);
458 }
459
460 if (need_lock)
461 rw_exit(&dp->dp_config_rwlock);
462 } else {
463 ds->ds_reserved = ds->ds_quota = 0;
464 }
465
466 if (err == 0) {
467 winner = dmu_buf_set_user_ie(dbuf, ds, &ds->ds_phys,
468 dsl_dataset_evict);
469 }
470 if (err || winner) {
428870ff
BB		 471 bplist_destroy(&ds->ds_pending_deadlist);
472 dsl_deadlist_close(&ds->ds_deadlist);
b128c09f
BB		 473 if (ds->ds_prev)
474 dsl_dataset_drop_ref(ds->ds_prev, ds);
34dc7c2f
BB		 475 dsl_dir_close(ds->ds_dir, ds);
476 mutex_destroy(&ds->ds_lock);
45d1cae3 477 mutex_destroy(&ds->ds_recvlock);
34dc7c2f 478 mutex_destroy(&ds->ds_opening_lock);
b128c09f
BB		 479 rw_destroy(&ds->ds_rwlock);
480 cv_destroy(&ds->ds_exclusive_cv);
34dc7c2f
BB		 481 kmem_free(ds, sizeof (dsl_dataset_t));
482 if (err) {
483 dmu_buf_rele(dbuf, tag);
484 return (err);
485 }
486 ds = winner;
487 } else {
488 ds->ds_fsid_guid =
489 unique_insert(ds->ds_phys->ds_fsid_guid);
490 }
491 }
492 ASSERT3P(ds->ds_dbuf, ==, dbuf);
493 ASSERT3P(ds->ds_phys, ==, dbuf->db_data);
b128c09f
BB		 494 ASSERT(ds->ds_phys->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);
34dc7c2f 497 mutex_enter(&ds->ds_lock);
b128c09f 498 if (!dsl_pool_sync_context(dp) && DSL_DATASET_IS_DESTROYED(ds)) {
34dc7c2f 499 mutex_exit(&ds->ds_lock);
b128c09f
BB		 500 dmu_buf_rele(ds->ds_dbuf, tag);
501 return (ENOENT);
34dc7c2f 502 }
34dc7c2f 503 mutex_exit(&ds->ds_lock);
34dc7c2f
BB		 504 *dsp = ds;
505 return (0);
506}
507
b128c09f
BB		 508static int
509dsl_dataset_hold_ref(dsl_dataset_t *ds, void *tag)
510{
511 dsl_pool_t *dp = ds->ds_dir->dd_pool;
512
513 /*
514 * In syncing context we don't want the rwlock lock: there
515 * may be an existing writer waiting for sync phase to
516 * finish. We don't need to worry about such writers, since
517 * sync phase is single-threaded, so the writer can't be
518 * doing anything while we are active.
519 */
520 if (dsl_pool_sync_context(dp)) {
521 ASSERT(!DSL_DATASET_IS_DESTROYED(ds));
522 return (0);
523 }
524
525 /*
526 * Normal users will hold the ds_rwlock as a READER until they
527 * are finished (i.e., call dsl_dataset_rele()). "Owners" will
528 * drop their READER lock after they set the ds_owner field.
529 *
530 * If the dataset is being destroyed, the destroy thread will
531 * obtain a WRITER lock for exclusive access after it's done its
532 * open-context work and then change the ds_owner to
533 * dsl_reaper once destruction is assured. So threads
534 * may block here temporarily, until the "destructability" of
535 * the dataset is determined.
536 */
537 ASSERT(!RW_WRITE_HELD(&dp->dp_config_rwlock));
538 mutex_enter(&ds->ds_lock);
539 while (!rw_tryenter(&ds->ds_rwlock, RW_READER)) {
540 rw_exit(&dp->dp_config_rwlock);
541 cv_wait(&ds->ds_exclusive_cv, &ds->ds_lock);
542 if (DSL_DATASET_IS_DESTROYED(ds)) {
543 mutex_exit(&ds->ds_lock);
544 dsl_dataset_drop_ref(ds, tag);
545 rw_enter(&dp->dp_config_rwlock, RW_READER);
546 return (ENOENT);
547 }
428870ff
BB		 548 /*
549 * The dp_config_rwlock lives above the ds_lock. And
550 * we need to check DSL_DATASET_IS_DESTROYED() while
551 * holding the ds_lock, so we have to drop and reacquire
552 * the ds_lock here.
553 */
554 mutex_exit(&ds->ds_lock);
b128c09f 555 rw_enter(&dp->dp_config_rwlock, RW_READER);
428870ff 556 mutex_enter(&ds->ds_lock);
b128c09f
BB		 557 }
558 mutex_exit(&ds->ds_lock);
559 return (0);
560}
561
34dc7c2f 562int
b128c09f
BB		 563dsl_dataset_hold_obj(dsl_pool_t *dp, uint64_t dsobj, void *tag,
564 dsl_dataset_t **dsp)
565{
566 int err = dsl_dataset_get_ref(dp, dsobj, tag, dsp);
567
568 if (err)
569 return (err);
570 return (dsl_dataset_hold_ref(*dsp, tag));
571}
572
573int
428870ff
BB		 574dsl_dataset_own_obj(dsl_pool_t *dp, uint64_t dsobj, boolean_t inconsistentok,
575 void *tag, dsl_dataset_t **dsp)
b128c09f 576{
428870ff 577 int err = dsl_dataset_hold_obj(dp, dsobj, tag, dsp);
b128c09f
BB		 578 if (err)
579 return (err);
428870ff
BB		 580 if (!dsl_dataset_tryown(*dsp, inconsistentok, tag)) {
581 dsl_dataset_rele(*dsp, tag);
9babb374 582 *dsp = NULL;
b128c09f
BB		 583 return (EBUSY);
584 }
585 return (0);
586}
587
588int
589dsl_dataset_hold(const char *name, void *tag, dsl_dataset_t **dsp)
34dc7c2f
BB		 590{
591 dsl_dir_t *dd;
592 dsl_pool_t *dp;
b128c09f 593 const char *snapname;
34dc7c2f 594 uint64_t obj;
34dc7c2f
BB		 595 int err = 0;
596
b128c09f 597 err = dsl_dir_open_spa(NULL, name, FTAG, &dd, &snapname);
34dc7c2f
BB		 598 if (err)
599 return (err);
600
601 dp = dd->dd_pool;
602 obj = dd->dd_phys->dd_head_dataset_obj;
603 rw_enter(&dp->dp_config_rwlock, RW_READER);
b128c09f
BB		 604 if (obj)
605 err = dsl_dataset_get_ref(dp, obj, tag, dsp);
606 else
34dc7c2f 607 err = ENOENT;
b128c09f 608 if (err)
34dc7c2f 609 goto out;
34dc7c2f 610
b128c09f 611 err = dsl_dataset_hold_ref(*dsp, tag);
34dc7c2f 612
b128c09f
BB		 613 /* we may be looking for a snapshot */
614 if (err == 0 && snapname != NULL) {
615 dsl_dataset_t *ds = NULL;
34dc7c2f 616
b128c09f
BB		 617 if (*snapname++ != '@') {
618 dsl_dataset_rele(*dsp, tag);
34dc7c2f
BB		 619 err = ENOENT;
620 goto out;
621 }
34dc7c2f 622
b128c09f
BB		 623 dprintf("looking for snapshot '%s'\n", snapname);
624 err = dsl_dataset_snap_lookup(*dsp, snapname, &obj);
625 if (err == 0)
626 err = dsl_dataset_get_ref(dp, obj, tag, &ds);
627 dsl_dataset_rele(*dsp, tag);
628
629 ASSERT3U((err == 0), ==, (ds != NULL));
630
631 if (ds) {
632 mutex_enter(&ds->ds_lock);
633 if (ds->ds_snapname[0] == 0)
634 (void) strlcpy(ds->ds_snapname, snapname,
635 sizeof (ds->ds_snapname));
636 mutex_exit(&ds->ds_lock);
637 err = dsl_dataset_hold_ref(ds, tag);
638 *dsp = err ? NULL : ds;
34dc7c2f 639 }
34dc7c2f 640 }
34dc7c2f
BB		 641out:
642 rw_exit(&dp->dp_config_rwlock);
643 dsl_dir_close(dd, FTAG);
34dc7c2f
BB		 644 return (err);
645}
646
647int
428870ff
BB		 648dsl_dataset_own(const char *name, boolean_t inconsistentok,
649 void *tag, dsl_dataset_t **dsp)
34dc7c2f 650{
428870ff 651 int err = dsl_dataset_hold(name, tag, dsp);
b128c09f
BB		 652 if (err)
653 return (err);
428870ff
BB		 654 if (!dsl_dataset_tryown(*dsp, inconsistentok, tag)) {
655 dsl_dataset_rele(*dsp, tag);
b128c09f
BB		 656 return (EBUSY);
657 }
658 return (0);
34dc7c2f
BB		 659}
660
661void
662dsl_dataset_name(dsl_dataset_t *ds, char *name)
663{
664 if (ds == NULL) {
665 (void) strcpy(name, "mos");
666 } else {
667 dsl_dir_name(ds->ds_dir, name);
668 VERIFY(0 == dsl_dataset_get_snapname(ds));
669 if (ds->ds_snapname[0]) {
670 (void) strcat(name, "@");
b128c09f
BB		 671 /*
672 * We use a "recursive" mutex so that we
673 * can call dprintf_ds() with ds_lock held.
674 */
34dc7c2f 675 if (!MUTEX_HELD(&ds->ds_lock)) {
34dc7c2f
BB		 676 mutex_enter(&ds->ds_lock);
677 (void) strcat(name, ds->ds_snapname);
678 mutex_exit(&ds->ds_lock);
679 } else {
680 (void) strcat(name, ds->ds_snapname);
681 }
682 }
683 }
684}
685
686static int
687dsl_dataset_namelen(dsl_dataset_t *ds)
688{
689 int result;
690
691 if (ds == NULL) {
692 result = 3; /* "mos" */
693 } else {
694 result = dsl_dir_namelen(ds->ds_dir);
695 VERIFY(0 == dsl_dataset_get_snapname(ds));
696 if (ds->ds_snapname[0]) {
697 ++result; /* adding one for the @-sign */
698 if (!MUTEX_HELD(&ds->ds_lock)) {
34dc7c2f
BB		 699 mutex_enter(&ds->ds_lock);
700 result += strlen(ds->ds_snapname);
701 mutex_exit(&ds->ds_lock);
702 } else {
703 result += strlen(ds->ds_snapname);
704 }
705 }
706 }
707
708 return (result);
709}
710
711void
b128c09f 712dsl_dataset_drop_ref(dsl_dataset_t *ds, void *tag)
34dc7c2f 713{
34dc7c2f
BB		 714 dmu_buf_rele(ds->ds_dbuf, tag);
715}
716
717void
b128c09f
BB		 718dsl_dataset_rele(dsl_dataset_t *ds, void *tag)
719{
720 if (!dsl_pool_sync_context(ds->ds_dir->dd_pool)) {
721 rw_exit(&ds->ds_rwlock);
722 }
723 dsl_dataset_drop_ref(ds, tag);
724}
725
726void
428870ff 727dsl_dataset_disown(dsl_dataset_t *ds, void *tag)
34dc7c2f 728{
428870ff 729 ASSERT((ds->ds_owner == tag && ds->ds_dbuf) ||
b128c09f
BB		 730 (DSL_DATASET_IS_DESTROYED(ds) && ds->ds_dbuf == NULL));
731
34dc7c2f 732 mutex_enter(&ds->ds_lock);
b128c09f
BB		 733 ds->ds_owner = NULL;
734 if (RW_WRITE_HELD(&ds->ds_rwlock)) {
735 rw_exit(&ds->ds_rwlock);
736 cv_broadcast(&ds->ds_exclusive_cv);
737 }
34dc7c2f 738 mutex_exit(&ds->ds_lock);
b128c09f 739 if (ds->ds_dbuf)
428870ff 740 dsl_dataset_drop_ref(ds, tag);
b128c09f 741 else
428870ff 742 dsl_dataset_evict(NULL, ds);
34dc7c2f
BB		 743}
744
745boolean_t
428870ff 746dsl_dataset_tryown(dsl_dataset_t *ds, boolean_t inconsistentok, void *tag)
34dc7c2f 747{
b128c09f
BB		 748 boolean_t gotit = FALSE;
749
34dc7c2f 750 mutex_enter(&ds->ds_lock);
b128c09f
BB		 751 if (ds->ds_owner == NULL &&
752 (!DS_IS_INCONSISTENT(ds) || inconsistentok)) {
428870ff 753 ds->ds_owner = tag;
b128c09f
BB		 754 if (!dsl_pool_sync_context(ds->ds_dir->dd_pool))
755 rw_exit(&ds->ds_rwlock);
756 gotit = TRUE;
34dc7c2f
BB		 757 }
758 mutex_exit(&ds->ds_lock);
b128c09f 759 return (gotit);
34dc7c2f
BB		 760}
761
762void
b128c09f 763dsl_dataset_make_exclusive(dsl_dataset_t *ds, void *owner)
34dc7c2f 764{
b128c09f
BB		 765 ASSERT3P(owner, ==, ds->ds_owner);
766 if (!RW_WRITE_HELD(&ds->ds_rwlock))
767 rw_enter(&ds->ds_rwlock, RW_WRITER);
34dc7c2f
BB		 768}
769
770uint64_t
b128c09f 771dsl_dataset_create_sync_dd(dsl_dir_t *dd, dsl_dataset_t *origin,
34dc7c2f
BB		 772 uint64_t flags, dmu_tx_t *tx)
773{
774 dsl_pool_t *dp = dd->dd_pool;
775 dmu_buf_t *dbuf;
776 dsl_dataset_phys_t *dsphys;
777 uint64_t dsobj;
778 objset_t *mos = dp->dp_meta_objset;
779
b128c09f
BB		 780 if (origin == NULL)
781 origin = dp->dp_origin_snap;
782
34dc7c2f
BB		 783 ASSERT(origin == NULL || origin->ds_dir->dd_pool == dp);
784 ASSERT(origin == NULL || origin->ds_phys->ds_num_children > 0);
785 ASSERT(dmu_tx_is_syncing(tx));
786 ASSERT(dd->dd_phys->dd_head_dataset_obj == 0);
787
788 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0,
789 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx);
790 VERIFY(0 == dmu_bonus_hold(mos, dsobj, FTAG, &dbuf));
791 dmu_buf_will_dirty(dbuf, tx);
792 dsphys = dbuf->db_data;
b128c09f 793 bzero(dsphys, sizeof (dsl_dataset_phys_t));
34dc7c2f
BB		 794 dsphys->ds_dir_obj = dd->dd_object;
795 dsphys->ds_flags = flags;
796 dsphys->ds_fsid_guid = unique_create();
797 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid,
798 sizeof (dsphys->ds_guid));
799 dsphys->ds_snapnames_zapobj =
800 zap_create_norm(mos, U8_TEXTPREP_TOUPPER, DMU_OT_DSL_DS_SNAP_MAP,
801 DMU_OT_NONE, 0, tx);
802 dsphys->ds_creation_time = gethrestime_sec();
b128c09f 803 dsphys->ds_creation_txg = tx->tx_txg == TXG_INITIAL ? 1 : tx->tx_txg;
34dc7c2f 804
428870ff
BB		 805 if (origin == NULL) {
806 dsphys->ds_deadlist_obj = dsl_deadlist_alloc(mos, tx);
807 } else {
808 dsl_dataset_t *ohds;
809
34dc7c2f
BB		 810 dsphys->ds_prev_snap_obj = origin->ds_object;
811 dsphys->ds_prev_snap_txg =
812 origin->ds_phys->ds_creation_txg;
813 dsphys->ds_used_bytes =
814 origin->ds_phys->ds_used_bytes;
815 dsphys->ds_compressed_bytes =
816 origin->ds_phys->ds_compressed_bytes;
817 dsphys->ds_uncompressed_bytes =
818 origin->ds_phys->ds_uncompressed_bytes;
819 dsphys->ds_bp = origin->ds_phys->ds_bp;
820 dsphys->ds_flags |= origin->ds_phys->ds_flags;
821
822 dmu_buf_will_dirty(origin->ds_dbuf, tx);
823 origin->ds_phys->ds_num_children++;
824
428870ff
BB		 825 VERIFY3U(0, ==, dsl_dataset_hold_obj(dp,
826 origin->ds_dir->dd_phys->dd_head_dataset_obj, FTAG, &ohds));
827 dsphys->ds_deadlist_obj = dsl_deadlist_clone(&ohds->ds_deadlist,
828 dsphys->ds_prev_snap_txg, dsphys->ds_prev_snap_obj, tx);
829 dsl_dataset_rele(ohds, FTAG);
830
b128c09f
BB		 831 if (spa_version(dp->dp_spa) >= SPA_VERSION_NEXT_CLONES) {
832 if (origin->ds_phys->ds_next_clones_obj == 0) {
833 origin->ds_phys->ds_next_clones_obj =
834 zap_create(mos,
835 DMU_OT_NEXT_CLONES, DMU_OT_NONE, 0, tx);
836 }
837 VERIFY(0 == zap_add_int(mos,
838 origin->ds_phys->ds_next_clones_obj,
839 dsobj, tx));
840 }
841
34dc7c2f
BB		 842 dmu_buf_will_dirty(dd->dd_dbuf, tx);
843 dd->dd_phys->dd_origin_obj = origin->ds_object;
428870ff
BB		 844 if (spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) {
845 if (origin->ds_dir->dd_phys->dd_clones == 0) {
846 dmu_buf_will_dirty(origin->ds_dir->dd_dbuf, tx);
847 origin->ds_dir->dd_phys->dd_clones =
848 zap_create(mos,
849 DMU_OT_DSL_CLONES, DMU_OT_NONE, 0, tx);
850 }
851 VERIFY3U(0, ==, zap_add_int(mos,
852 origin->ds_dir->dd_phys->dd_clones, dsobj, tx));
853 }
34dc7c2f
BB		 854 }
855
856 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE)
857 dsphys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE;
858
859 dmu_buf_rele(dbuf, FTAG);
860
861 dmu_buf_will_dirty(dd->dd_dbuf, tx);
862 dd->dd_phys->dd_head_dataset_obj = dsobj;
863
864 return (dsobj);
865}
866
867uint64_t
868dsl_dataset_create_sync(dsl_dir_t *pdd, const char *lastname,
869 dsl_dataset_t *origin, uint64_t flags, cred_t *cr, dmu_tx_t *tx)
870{
871 dsl_pool_t *dp = pdd->dd_pool;
872 uint64_t dsobj, ddobj;
873 dsl_dir_t *dd;
874
875 ASSERT(lastname[0] != '@');
876
b128c09f 877 ddobj = dsl_dir_create_sync(dp, pdd, lastname, tx);
34dc7c2f
BB		 878 VERIFY(0 == dsl_dir_open_obj(dp, ddobj, lastname, FTAG, &dd));
879
b128c09f 880 dsobj = dsl_dataset_create_sync_dd(dd, origin, flags, tx);
34dc7c2f
BB		 881
882 dsl_deleg_set_create_perms(dd, tx, cr);
883
884 dsl_dir_close(dd, FTAG);
885
572e2857
BB		 886 /*
887 * If we are creating a clone, make sure we zero out any stale
888 * data from the origin snapshots zil header.
889 */
890 if (origin != NULL) {
891 dsl_dataset_t *ds;
892 objset_t *os;
893
894 VERIFY3U(0, ==, dsl_dataset_hold_obj(dp, dsobj, FTAG, &ds));
895 VERIFY3U(0, ==, dmu_objset_from_ds(ds, &os));
896 bzero(&os->os_zil_header, sizeof (os->os_zil_header));
897 dsl_dataset_dirty(ds, tx);
898 dsl_dataset_rele(ds, FTAG);
899 }
900
34dc7c2f
BB		 901 return (dsobj);
902}
903
904struct destroyarg {
905 dsl_sync_task_group_t *dstg;
906 char *snapname;
907 char *failed;
45d1cae3 908 boolean_t defer;
34dc7c2f
BB		 909};
910
911static int
428870ff 912dsl_snapshot_destroy_one(const char *name, void *arg)
34dc7c2f
BB		 913{
914 struct destroyarg *da = arg;
915 dsl_dataset_t *ds;
34dc7c2f 916 int err;
45d1cae3 917 char *dsname;
428870ff
BB		 918
919 dsname = kmem_asprintf("%s@%s", name, da->snapname);
920 err = dsl_dataset_own(dsname, B_TRUE, da->dstg, &ds);
921 strfree(dsname);
b128c09f 922 if (err == 0) {
45d1cae3
BB		 923 struct dsl_ds_destroyarg *dsda;
924
b128c09f 925 dsl_dataset_make_exclusive(ds, da->dstg);
45d1cae3
BB		 926 dsda = kmem_zalloc(sizeof (struct dsl_ds_destroyarg), KM_SLEEP);
927 dsda->ds = ds;
928 dsda->defer = da->defer;
b128c09f 929 dsl_sync_task_create(da->dstg, dsl_dataset_destroy_check,
45d1cae3 930 dsl_dataset_destroy_sync, dsda, da->dstg, 0);
b128c09f
BB		 931 } else if (err == ENOENT) {
932 err = 0;
933 } else {
34dc7c2f 934 (void) strcpy(da->failed, name);
34dc7c2f 935 }
b128c09f 936 return (err);
34dc7c2f
BB		 937}
938
939/*
940 * Destroy 'snapname' in all descendants of 'fsname'.
941 */
942#pragma weak dmu_snapshots_destroy = dsl_snapshots_destroy
943int
45d1cae3 944dsl_snapshots_destroy(char *fsname, char *snapname, boolean_t defer)
34dc7c2f
BB		 945{
946 int err;
947 struct destroyarg da;
948 dsl_sync_task_t *dst;
949 spa_t *spa;
950
951 err = spa_open(fsname, &spa, FTAG);
952 if (err)
953 return (err);
954 da.dstg = dsl_sync_task_group_create(spa_get_dsl(spa));
955 da.snapname = snapname;
956 da.failed = fsname;
45d1cae3 957 da.defer = defer;
34dc7c2f
BB		 958
959 err = dmu_objset_find(fsname,
960 dsl_snapshot_destroy_one, &da, DS_FIND_CHILDREN);
961
962 if (err == 0)
963 err = dsl_sync_task_group_wait(da.dstg);
964
965 for (dst = list_head(&da.dstg->dstg_tasks); dst;
966 dst = list_next(&da.dstg->dstg_tasks, dst)) {
45d1cae3
BB		 967 struct dsl_ds_destroyarg *dsda = dst->dst_arg1;
968 dsl_dataset_t *ds = dsda->ds;
969
b128c09f
BB		 970 /*
971 * Return the file system name that triggered the error
972 */
34dc7c2f
BB		 973 if (dst->dst_err) {
974 dsl_dataset_name(ds, fsname);
975 *strchr(fsname, '@') = '\0';
976 }
45d1cae3 977 ASSERT3P(dsda->rm_origin, ==, NULL);
b128c09f 978 dsl_dataset_disown(ds, da.dstg);
45d1cae3 979 kmem_free(dsda, sizeof (struct dsl_ds_destroyarg));
34dc7c2f
BB		 980 }
981
982 dsl_sync_task_group_destroy(da.dstg);
983 spa_close(spa, FTAG);
984 return (err);
985}
986
45d1cae3
BB		 987static boolean_t
988dsl_dataset_might_destroy_origin(dsl_dataset_t *ds)
989{
990 boolean_t might_destroy = B_FALSE;
991
992 mutex_enter(&ds->ds_lock);
993 if (ds->ds_phys->ds_num_children == 2 && ds->ds_userrefs == 0 &&
994 DS_IS_DEFER_DESTROY(ds))
995 might_destroy = B_TRUE;
996 mutex_exit(&ds->ds_lock);
997
998 return (might_destroy);
999}
1000
45d1cae3
BB		 1001/*
1002 * If we're removing a clone, and these three conditions are true:
1003 * 1) the clone's origin has no other children
1004 * 2) the clone's origin has no user references
1005 * 3) the clone's origin has been marked for deferred destruction
1006 * Then, prepare to remove the origin as part of this sync task group.
1007 */
1008static int
1009dsl_dataset_origin_rm_prep(struct dsl_ds_destroyarg *dsda, void *tag)
1010{
1011 dsl_dataset_t *ds = dsda->ds;
1012 dsl_dataset_t *origin = ds->ds_prev;
1013
1014 if (dsl_dataset_might_destroy_origin(origin)) {
1015 char *name;
1016 int namelen;
1017 int error;
1018
1019 namelen = dsl_dataset_namelen(origin) + 1;
1020 name = kmem_alloc(namelen, KM_SLEEP);
1021 dsl_dataset_name(origin, name);
1022#ifdef _KERNEL
1023 error = zfs_unmount_snap(name, NULL);
1024 if (error) {
1025 kmem_free(name, namelen);
1026 return (error);
1027 }
45d1cae3 1028#endif
428870ff 1029 error = dsl_dataset_own(name, B_TRUE, tag, &origin);
45d1cae3
BB		 1030 kmem_free(name, namelen);
1031 if (error)
1032 return (error);
1033 dsda->rm_origin = origin;
1034 dsl_dataset_make_exclusive(origin, tag);
1035 }
1036
1037 return (0);
1038}
1039
34dc7c2f 1040/*
b128c09f
BB		 1041 * ds must be opened as OWNER. On return (whether successful or not),
1042 * ds will be closed and caller can no longer dereference it.
34dc7c2f
BB		 1043 */
1044int
45d1cae3 1045dsl_dataset_destroy(dsl_dataset_t *ds, void *tag, boolean_t defer)
34dc7c2f
BB		 1046{
1047 int err;
1048 dsl_sync_task_group_t *dstg;
1049 objset_t *os;
1050 dsl_dir_t *dd;
1051 uint64_t obj;
428870ff
BB		 1052 struct dsl_ds_destroyarg dsda = { 0 };
1053 dsl_dataset_t dummy_ds = { 0 };
45d1cae3
BB		 1054
1055 dsda.ds = ds;
34dc7c2f 1056
34dc7c2f
BB		 1057 if (dsl_dataset_is_snapshot(ds)) {
1058 /* Destroying a snapshot is simpler */
b128c09f
BB		 1059 dsl_dataset_make_exclusive(ds, tag);
1060
45d1cae3 1061 dsda.defer = defer;
34dc7c2f
BB		 1062 err = dsl_sync_task_do(ds->ds_dir->dd_pool,
1063 dsl_dataset_destroy_check, dsl_dataset_destroy_sync,
45d1cae3
BB		 1064 &dsda, tag, 0);
1065 ASSERT3P(dsda.rm_origin, ==, NULL);
34dc7c2f 1066 goto out;
428870ff
BB		 1067 } else if (defer) {
1068 err = EINVAL;
1069 goto out;
34dc7c2f
BB		 1070 }
1071
1072 dd = ds->ds_dir;
428870ff
BB		 1073 dummy_ds.ds_dir = dd;
1074 dummy_ds.ds_object = ds->ds_object;
34dc7c2f
BB		 1075
1076 /*
1077 * Check for errors and mark this ds as inconsistent, in
1078 * case we crash while freeing the objects.
1079 */
1080 err = dsl_sync_task_do(dd->dd_pool, dsl_dataset_destroy_begin_check,
1081 dsl_dataset_destroy_begin_sync, ds, NULL, 0);
1082 if (err)
1083 goto out;
1084
428870ff 1085 err = dmu_objset_from_ds(ds, &os);
34dc7c2f
BB		 1086 if (err)
1087 goto out;
1088
1089 /*
1090 * remove the objects in open context, so that we won't
1091 * have too much to do in syncing context.
1092 */
1093 for (obj = 0; err == 0; err = dmu_object_next(os, &obj, FALSE,
1094 ds->ds_phys->ds_prev_snap_txg)) {
b128c09f
BB		 1095 /*
1096 * Ignore errors, if there is not enough disk space
1097 * we will deal with it in dsl_dataset_destroy_sync().
1098 */
1099 (void) dmu_free_object(os, obj);
34dc7c2f 1100 }
572e2857
BB		 1101 if (err != ESRCH)
1102 goto out;
34dc7c2f 1103
9babb374 1104 /*
572e2857
BB		 1105 * Only the ZIL knows how to free log blocks.
1106 */
1107 zil_destroy(dmu_objset_zil(os), B_FALSE);
1108
1109 /*
1110 * Sync out all in-flight IO.
9babb374
BB		 1111 */
1112 txg_wait_synced(dd->dd_pool, 0);
1113
1114 /*
1115 * If we managed to free all the objects in open
1116 * context, the user space accounting should be zero.
1117 */
1118 if (ds->ds_phys->ds_bp.blk_fill == 0 &&
428870ff 1119 dmu_objset_userused_enabled(os)) {
9babb374
BB		 1120 uint64_t count;
1121
1122 ASSERT(zap_count(os, DMU_USERUSED_OBJECT, &count) != 0 ||
1123 count == 0);
1124 ASSERT(zap_count(os, DMU_GROUPUSED_OBJECT, &count) != 0 ||
1125 count == 0);
1126 }
1127
34dc7c2f
BB		 1128 rw_enter(&dd->dd_pool->dp_config_rwlock, RW_READER);
1129 err = dsl_dir_open_obj(dd->dd_pool, dd->dd_object, NULL, FTAG, &dd);
1130 rw_exit(&dd->dd_pool->dp_config_rwlock);
1131
1132 if (err)
1133 goto out;
1134
1135 /*
1136 * Blow away the dsl_dir + head dataset.
1137 */
b128c09f 1138 dsl_dataset_make_exclusive(ds, tag);
45d1cae3
BB		 1139 /*
1140 * If we're removing a clone, we might also need to remove its
1141 * origin.
1142 */
1143 do {
1144 dsda.need_prep = B_FALSE;
1145 if (dsl_dir_is_clone(dd)) {
1146 err = dsl_dataset_origin_rm_prep(&dsda, tag);
1147 if (err) {
1148 dsl_dir_close(dd, FTAG);
1149 goto out;
1150 }
1151 }
1152
1153 dstg = dsl_sync_task_group_create(ds->ds_dir->dd_pool);
1154 dsl_sync_task_create(dstg, dsl_dataset_destroy_check,
1155 dsl_dataset_destroy_sync, &dsda, tag, 0);
1156 dsl_sync_task_create(dstg, dsl_dir_destroy_check,
428870ff 1157 dsl_dir_destroy_sync, &dummy_ds, FTAG, 0);
45d1cae3
BB		 1158 err = dsl_sync_task_group_wait(dstg);
1159 dsl_sync_task_group_destroy(dstg);
1160
1161 /*
1162 * We could be racing against 'zfs release' or 'zfs destroy -d'
1163 * on the origin snap, in which case we can get EBUSY if we
1164 * needed to destroy the origin snap but were not ready to
1165 * do so.
1166 */
1167 if (dsda.need_prep) {
1168 ASSERT(err == EBUSY);
1169 ASSERT(dsl_dir_is_clone(dd));
1170 ASSERT(dsda.rm_origin == NULL);
1171 }
1172 } while (dsda.need_prep);
1173
1174 if (dsda.rm_origin != NULL)
1175 dsl_dataset_disown(dsda.rm_origin, tag);
1176
b128c09f 1177 /* if it is successful, dsl_dir_destroy_sync will close the dd */
34dc7c2f
BB		 1178 if (err)
1179 dsl_dir_close(dd, FTAG);
1180out:
b128c09f 1181 dsl_dataset_disown(ds, tag);
34dc7c2f
BB		 1182 return (err);
1183}
1184
34dc7c2f
BB		 1185blkptr_t *
1186dsl_dataset_get_blkptr(dsl_dataset_t *ds)
1187{
1188 return (&ds->ds_phys->ds_bp);
1189}
1190
1191void
1192dsl_dataset_set_blkptr(dsl_dataset_t *ds, blkptr_t *bp, dmu_tx_t *tx)
1193{
1194 ASSERT(dmu_tx_is_syncing(tx));
1195 /* If it's the meta-objset, set dp_meta_rootbp */
1196 if (ds == NULL) {
1197 tx->tx_pool->dp_meta_rootbp = *bp;
1198 } else {
1199 dmu_buf_will_dirty(ds->ds_dbuf, tx);
1200 ds->ds_phys->ds_bp = *bp;
1201 }
1202}
1203
1204spa_t *
1205dsl_dataset_get_spa(dsl_dataset_t *ds)
1206{
1207 return (ds->ds_dir->dd_pool->dp_spa);
1208}
1209
1210void
1211dsl_dataset_dirty(dsl_dataset_t *ds, dmu_tx_t *tx)
1212{
1213 dsl_pool_t *dp;
1214
1215 if (ds == NULL) /* this is the meta-objset */
1216 return;
1217
428870ff 1218 ASSERT(ds->ds_objset != NULL);
34dc7c2f
BB		 1219
1220 if (ds->ds_phys->ds_next_snap_obj != 0)
1221 panic("dirtying snapshot!");
1222
1223 dp = ds->ds_dir->dd_pool;
1224
1225 if (txg_list_add(&dp->dp_dirty_datasets, ds, tx->tx_txg) == 0) {
1226 /* up the hold count until we can be written out */
1227 dmu_buf_add_ref(ds->ds_dbuf, ds);
1228 }
1229}
1230
1231/*
1232 * The unique space in the head dataset can be calculated by subtracting
1233 * the space used in the most recent snapshot, that is still being used
1234 * in this file system, from the space currently in use. To figure out
1235 * the space in the most recent snapshot still in use, we need to take
1236 * the total space used in the snapshot and subtract out the space that
1237 * has been freed up since the snapshot was taken.
1238 */
1239static void
1240dsl_dataset_recalc_head_uniq(dsl_dataset_t *ds)
1241{
1242 uint64_t mrs_used;
1243 uint64_t dlused, dlcomp, dluncomp;
1244
428870ff 1245 ASSERT(!dsl_dataset_is_snapshot(ds));
34dc7c2f
BB		 1246
1247 if (ds->ds_phys->ds_prev_snap_obj != 0)
1248 mrs_used = ds->ds_prev->ds_phys->ds_used_bytes;
1249 else
1250 mrs_used = 0;
1251
428870ff 1252 dsl_deadlist_space(&ds->ds_deadlist, &dlused, &dlcomp, &dluncomp);
34dc7c2f
BB		 1253
1254 ASSERT3U(dlused, <=, mrs_used);
1255 ds->ds_phys->ds_unique_bytes =
1256 ds->ds_phys->ds_used_bytes - (mrs_used - dlused);
1257
428870ff 1258 if (spa_version(ds->ds_dir->dd_pool->dp_spa) >=
34dc7c2f
BB		 1259 SPA_VERSION_UNIQUE_ACCURATE)
1260 ds->ds_phys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE;
1261}
1262
34dc7c2f 1263struct killarg {
b128c09f 1264 dsl_dataset_t *ds;
34dc7c2f
BB		 1265 dmu_tx_t *tx;
1266};
1267
b128c09f 1268/* ARGSUSED */
34dc7c2f 1269static int
428870ff
BB		 1270kill_blkptr(spa_t *spa, zilog_t *zilog, const blkptr_t *bp, arc_buf_t *pbuf,
1271 const zbookmark_t *zb, const dnode_phys_t *dnp, void *arg)
34dc7c2f
BB		 1272{
1273 struct killarg *ka = arg;
428870ff 1274 dmu_tx_t *tx = ka->tx;
34dc7c2f 1275
b128c09f
BB		 1276 if (bp == NULL)
1277 return (0);
1278
428870ff
BB		 1279 if (zb->zb_level == ZB_ZIL_LEVEL) {
1280 ASSERT(zilog != NULL);
9babb374
BB		 1281 /*
1282 * It's a block in the intent log. It has no
1283 * accounting, so just free it.
1284 */
428870ff 1285 dsl_free(ka->tx->tx_pool, ka->tx->tx_txg, bp);
9babb374 1286 } else {
428870ff 1287 ASSERT(zilog == NULL);
9babb374 1288 ASSERT3U(bp->blk_birth, >, ka->ds->ds_phys->ds_prev_snap_txg);
428870ff 1289 (void) dsl_dataset_block_kill(ka->ds, bp, tx, B_FALSE);
9babb374 1290 }
34dc7c2f 1291
34dc7c2f
BB		 1292 return (0);
1293}
1294
34dc7c2f
BB		 1295/* ARGSUSED */
1296static int
1297dsl_dataset_destroy_begin_check(void *arg1, void *arg2, dmu_tx_t *tx)
1298{
1299 dsl_dataset_t *ds = arg1;
1300 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
1301 uint64_t count;
1302 int err;
1303
1304 /*
1305 * Can't delete a head dataset if there are snapshots of it.
1306 * (Except if the only snapshots are from the branch we cloned
1307 * from.)
1308 */
1309 if (ds->ds_prev != NULL &&
1310 ds->ds_prev->ds_phys->ds_next_snap_obj == ds->ds_object)
428870ff 1311 return (EBUSY);
34dc7c2f
BB		 1312
1313 /*
1314 * This is really a dsl_dir thing, but check it here so that
1315 * we'll be less likely to leave this dataset inconsistent &
1316 * nearly destroyed.
1317 */
1318 err = zap_count(mos, ds->ds_dir->dd_phys->dd_child_dir_zapobj, &count);
1319 if (err)
1320 return (err);
1321 if (count != 0)
1322 return (EEXIST);
1323
1324 return (0);
1325}
1326
1327/* ARGSUSED */
1328static void
428870ff 1329dsl_dataset_destroy_begin_sync(void *arg1, void *arg2, dmu_tx_t *tx)
34dc7c2f
BB		 1330{
1331 dsl_dataset_t *ds = arg1;
1332 dsl_pool_t *dp = ds->ds_dir->dd_pool;
1333
1334 /* Mark it as inconsistent on-disk, in case we crash */
1335 dmu_buf_will_dirty(ds->ds_dbuf, tx);
1336 ds->ds_phys->ds_flags |= DS_FLAG_INCONSISTENT;
1337
428870ff
BB		 1338 spa_history_log_internal(LOG_DS_DESTROY_BEGIN, dp->dp_spa, tx,
1339 "dataset = %llu", ds->ds_object);
34dc7c2f
BB		 1340}
1341
45d1cae3
BB		 1342static int
1343dsl_dataset_origin_check(struct dsl_ds_destroyarg *dsda, void *tag,
1344 dmu_tx_t *tx)
1345{
1346 dsl_dataset_t *ds = dsda->ds;
1347 dsl_dataset_t *ds_prev = ds->ds_prev;
1348
1349 if (dsl_dataset_might_destroy_origin(ds_prev)) {
1350 struct dsl_ds_destroyarg ndsda = {0};
1351
1352 /*
1353 * If we're not prepared to remove the origin, don't remove
1354 * the clone either.
1355 */
1356 if (dsda->rm_origin == NULL) {
1357 dsda->need_prep = B_TRUE;
1358 return (EBUSY);
1359 }
1360
1361 ndsda.ds = ds_prev;
1362 ndsda.is_origin_rm = B_TRUE;
1363 return (dsl_dataset_destroy_check(&ndsda, tag, tx));
1364 }
1365
1366 /*
1367 * If we're not going to remove the origin after all,
1368 * undo the open context setup.
1369 */
1370 if (dsda->rm_origin != NULL) {
1371 dsl_dataset_disown(dsda->rm_origin, tag);
1372 dsda->rm_origin = NULL;
1373 }
1374
1375 return (0);
1376}
1377
572e2857
BB		 1378/*
1379 * If you add new checks here, you may need to add
1380 * additional checks to the "temporary" case in
1381 * snapshot_check() in dmu_objset.c.
1382 */
34dc7c2f
BB		 1383/* ARGSUSED */
1384int
1385dsl_dataset_destroy_check(void *arg1, void *arg2, dmu_tx_t *tx)
1386{
45d1cae3
BB		 1387 struct dsl_ds_destroyarg *dsda = arg1;
1388 dsl_dataset_t *ds = dsda->ds;
34dc7c2f 1389
b128c09f
BB		 1390 /* we have an owner hold, so noone else can destroy us */
1391 ASSERT(!DSL_DATASET_IS_DESTROYED(ds));
1392
45d1cae3
BB		 1393 /*
1394 * Only allow deferred destroy on pools that support it.
1395 * NOTE: deferred destroy is only supported on snapshots.
1396 */
1397 if (dsda->defer) {
1398 if (spa_version(ds->ds_dir->dd_pool->dp_spa) <
1399 SPA_VERSION_USERREFS)
1400 return (ENOTSUP);
1401 ASSERT(dsl_dataset_is_snapshot(ds));
1402 return (0);
1403 }
34dc7c2f
BB		 1404
1405 /*
1406 * Can't delete a head dataset if there are snapshots of it.
1407 * (Except if the only snapshots are from the branch we cloned
1408 * from.)
1409 */
1410 if (ds->ds_prev != NULL &&
1411 ds->ds_prev->ds_phys->ds_next_snap_obj == ds->ds_object)
428870ff 1412 return (EBUSY);
34dc7c2f
BB		 1413
1414 /*
1415 * If we made changes this txg, traverse_dsl_dataset won't find
1416 * them. Try again.
1417 */
1418 if (ds->ds_phys->ds_bp.blk_birth >= tx->tx_txg)
1419 return (EAGAIN);
1420
45d1cae3
BB		 1421 if (dsl_dataset_is_snapshot(ds)) {
1422 /*
1423 * If this snapshot has an elevated user reference count,
1424 * we can't destroy it yet.
1425 */
1426 if (ds->ds_userrefs > 0 && !dsda->releasing)
1427 return (EBUSY);
1428
1429 mutex_enter(&ds->ds_lock);
1430 /*
1431 * Can't delete a branch point. However, if we're destroying
1432 * a clone and removing its origin due to it having a user
1433 * hold count of 0 and having been marked for deferred destroy,
1434 * it's OK for the origin to have a single clone.
1435 */
1436 if (ds->ds_phys->ds_num_children >
1437 (dsda->is_origin_rm ? 2 : 1)) {
1438 mutex_exit(&ds->ds_lock);
1439 return (EEXIST);
1440 }
1441 mutex_exit(&ds->ds_lock);
1442 } else if (dsl_dir_is_clone(ds->ds_dir)) {
1443 return (dsl_dataset_origin_check(dsda, arg2, tx));
1444 }
1445
34dc7c2f
BB		 1446 /* XXX we should do some i/o error checking... */
1447 return (0);
1448}
1449
b128c09f
BB		 1450struct refsarg {
1451 kmutex_t lock;
1452 boolean_t gone;
1453 kcondvar_t cv;
1454};
1455
1456/* ARGSUSED */
1457static void
1458dsl_dataset_refs_gone(dmu_buf_t *db, void *argv)
1459{
1460 struct refsarg *arg = argv;
1461
1462 mutex_enter(&arg->lock);
1463 arg->gone = TRUE;
1464 cv_signal(&arg->cv);
1465 mutex_exit(&arg->lock);
1466}
1467
1468static void
1469dsl_dataset_drain_refs(dsl_dataset_t *ds, void *tag)
1470{
1471 struct refsarg arg;
1472
1473 mutex_init(&arg.lock, NULL, MUTEX_DEFAULT, NULL);
1474 cv_init(&arg.cv, NULL, CV_DEFAULT, NULL);
1475 arg.gone = FALSE;
1476 (void) dmu_buf_update_user(ds->ds_dbuf, ds, &arg, &ds->ds_phys,
1477 dsl_dataset_refs_gone);
1478 dmu_buf_rele(ds->ds_dbuf, tag);
1479 mutex_enter(&arg.lock);
1480 while (!arg.gone)
1481 cv_wait(&arg.cv, &arg.lock);
1482 ASSERT(arg.gone);
1483 mutex_exit(&arg.lock);
1484 ds->ds_dbuf = NULL;
1485 ds->ds_phys = NULL;
1486 mutex_destroy(&arg.lock);
1487 cv_destroy(&arg.cv);
1488}
1489
428870ff
BB		 1490static void
1491remove_from_next_clones(dsl_dataset_t *ds, uint64_t obj, dmu_tx_t *tx)
1492{
1493 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
1494 uint64_t count;
1495 int err;
1496
1497 ASSERT(ds->ds_phys->ds_num_children >= 2);
1498 err = zap_remove_int(mos, ds->ds_phys->ds_next_clones_obj, obj, tx);
1499 /*
1500 * The err should not be ENOENT, but a bug in a previous version
1501 * of the code could cause upgrade_clones_cb() to not set
1502 * ds_next_snap_obj when it should, leading to a missing entry.
1503 * If we knew that the pool was created after
1504 * SPA_VERSION_NEXT_CLONES, we could assert that it isn't
1505 * ENOENT. However, at least we can check that we don't have
1506 * too many entries in the next_clones_obj even after failing to
1507 * remove this one.
1508 */
1509 if (err != ENOENT) {
1510 VERIFY3U(err, ==, 0);
1511 }
1512 ASSERT3U(0, ==, zap_count(mos, ds->ds_phys->ds_next_clones_obj,
1513 &count));
1514 ASSERT3U(count, <=, ds->ds_phys->ds_num_children - 2);
1515}
1516
1517static void
1518dsl_dataset_remove_clones_key(dsl_dataset_t *ds, uint64_t mintxg, dmu_tx_t *tx)
1519{
1520 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
1521 zap_cursor_t zc;
1522 zap_attribute_t za;
1523
1524 /*
1525 * If it is the old version, dd_clones doesn't exist so we can't
1526 * find the clones, but deadlist_remove_key() is a no-op so it
1527 * doesn't matter.
1528 */
1529 if (ds->ds_dir->dd_phys->dd_clones == 0)
1530 return;
1531
1532 for (zap_cursor_init(&zc, mos, ds->ds_dir->dd_phys->dd_clones);
1533 zap_cursor_retrieve(&zc, &za) == 0;
1534 zap_cursor_advance(&zc)) {
1535 dsl_dataset_t *clone;
1536
1537 VERIFY3U(0, ==, dsl_dataset_hold_obj(ds->ds_dir->dd_pool,
1538 za.za_first_integer, FTAG, &clone));
1539 if (clone->ds_dir->dd_origin_txg > mintxg) {
1540 dsl_deadlist_remove_key(&clone->ds_deadlist,
1541 mintxg, tx);
1542 dsl_dataset_remove_clones_key(clone, mintxg, tx);
1543 }
1544 dsl_dataset_rele(clone, FTAG);
1545 }
1546 zap_cursor_fini(&zc);
1547}
1548
1549struct process_old_arg {
1550 dsl_dataset_t *ds;
1551 dsl_dataset_t *ds_prev;
1552 boolean_t after_branch_point;
1553 zio_t *pio;
1554 uint64_t used, comp, uncomp;
1555};
1556
1557static int
1558process_old_cb(void *arg, const blkptr_t *bp, dmu_tx_t *tx)
1559{
1560 struct process_old_arg *poa = arg;
1561 dsl_pool_t *dp = poa->ds->ds_dir->dd_pool;
1562
1563 if (bp->blk_birth <= poa->ds->ds_phys->ds_prev_snap_txg) {
1564 dsl_deadlist_insert(&poa->ds->ds_deadlist, bp, tx);
1565 if (poa->ds_prev && !poa->after_branch_point &&
1566 bp->blk_birth >
1567 poa->ds_prev->ds_phys->ds_prev_snap_txg) {
1568 poa->ds_prev->ds_phys->ds_unique_bytes +=
1569 bp_get_dsize_sync(dp->dp_spa, bp);
1570 }
1571 } else {
1572 poa->used += bp_get_dsize_sync(dp->dp_spa, bp);
1573 poa->comp += BP_GET_PSIZE(bp);
1574 poa->uncomp += BP_GET_UCSIZE(bp);
1575 dsl_free_sync(poa->pio, dp, tx->tx_txg, bp);
1576 }
1577 return (0);
1578}
1579
1580static void
1581process_old_deadlist(dsl_dataset_t *ds, dsl_dataset_t *ds_prev,
1582 dsl_dataset_t *ds_next, boolean_t after_branch_point, dmu_tx_t *tx)
1583{
1584 struct process_old_arg poa = { 0 };
1585 dsl_pool_t *dp = ds->ds_dir->dd_pool;
1586 objset_t *mos = dp->dp_meta_objset;
1587
1588 ASSERT(ds->ds_deadlist.dl_oldfmt);
1589 ASSERT(ds_next->ds_deadlist.dl_oldfmt);
1590
1591 poa.ds = ds;
1592 poa.ds_prev = ds_prev;
1593 poa.after_branch_point = after_branch_point;
1594 poa.pio = zio_root(dp->dp_spa, NULL, NULL, ZIO_FLAG_MUSTSUCCEED);
1595 VERIFY3U(0, ==, bpobj_iterate(&ds_next->ds_deadlist.dl_bpobj,
1596 process_old_cb, &poa, tx));
1597 VERIFY3U(zio_wait(poa.pio), ==, 0);
1598 ASSERT3U(poa.used, ==, ds->ds_phys->ds_unique_bytes);
1599
1600 /* change snapused */
1601 dsl_dir_diduse_space(ds->ds_dir, DD_USED_SNAP,
1602 -poa.used, -poa.comp, -poa.uncomp, tx);
1603
1604 /* swap next's deadlist to our deadlist */
1605 dsl_deadlist_close(&ds->ds_deadlist);
1606 dsl_deadlist_close(&ds_next->ds_deadlist);
1607 SWITCH64(ds_next->ds_phys->ds_deadlist_obj,
1608 ds->ds_phys->ds_deadlist_obj);
1609 dsl_deadlist_open(&ds->ds_deadlist, mos, ds->ds_phys->ds_deadlist_obj);
1610 dsl_deadlist_open(&ds_next->ds_deadlist, mos,
1611 ds_next->ds_phys->ds_deadlist_obj);
1612}
1613
34dc7c2f 1614void
428870ff 1615dsl_dataset_destroy_sync(void *arg1, void *tag, dmu_tx_t *tx)
34dc7c2f 1616{
45d1cae3
BB		 1617 struct dsl_ds_destroyarg *dsda = arg1;
1618 dsl_dataset_t *ds = dsda->ds;
34dc7c2f
BB		 1619 int err;
1620 int after_branch_point = FALSE;
1621 dsl_pool_t *dp = ds->ds_dir->dd_pool;
1622 objset_t *mos = dp->dp_meta_objset;
1623 dsl_dataset_t *ds_prev = NULL;
572e2857 1624 boolean_t wont_destroy;
34dc7c2f
BB		 1625 uint64_t obj;
1626
572e2857
BB		 1627 wont_destroy = (dsda->defer &&
1628 (ds->ds_userrefs > 0 || ds->ds_phys->ds_num_children > 1));
1629
1630 ASSERT(ds->ds_owner || wont_destroy);
45d1cae3 1631 ASSERT(dsda->defer || ds->ds_phys->ds_num_children <= 1);
34dc7c2f
BB		 1632 ASSERT(ds->ds_prev == NULL ||
1633 ds->ds_prev->ds_phys->ds_next_snap_obj != ds->ds_object);
1634 ASSERT3U(ds->ds_phys->ds_bp.blk_birth, <=, tx->tx_txg);
1635
572e2857 1636 if (wont_destroy) {
45d1cae3 1637 ASSERT(spa_version(dp->dp_spa) >= SPA_VERSION_USERREFS);
572e2857
BB		 1638 dmu_buf_will_dirty(ds->ds_dbuf, tx);
1639 ds->ds_phys->ds_flags |= DS_FLAG_DEFER_DESTROY;
1640 return;
45d1cae3
BB		 1641 }
1642
b128c09f
BB		 1643 /* signal any waiters that this dataset is going away */
1644 mutex_enter(&ds->ds_lock);
1645 ds->ds_owner = dsl_reaper;
1646 cv_broadcast(&ds->ds_exclusive_cv);
1647 mutex_exit(&ds->ds_lock);
1648
34dc7c2f
BB		 1649 /* Remove our reservation */
1650 if (ds->ds_reserved != 0) {
428870ff
BB		 1651 dsl_prop_setarg_t psa;
1652 uint64_t value = 0;
1653
1654 dsl_prop_setarg_init_uint64(&psa, "refreservation",
1655 (ZPROP_SRC_NONE | ZPROP_SRC_LOCAL | ZPROP_SRC_RECEIVED),
1656 &value);
1657 psa.psa_effective_value = 0; /* predict default value */
1658
1659 dsl_dataset_set_reservation_sync(ds, &psa, tx);
34dc7c2f
BB		 1660 ASSERT3U(ds->ds_reserved, ==, 0);
1661 }
1662
1663 ASSERT(RW_WRITE_HELD(&dp->dp_config_rwlock));
1664
428870ff 1665 dsl_scan_ds_destroyed(ds, tx);
b128c09f 1666
34dc7c2f
BB		 1667 obj = ds->ds_object;
1668
1669 if (ds->ds_phys->ds_prev_snap_obj != 0) {
1670 if (ds->ds_prev) {
1671 ds_prev = ds->ds_prev;
1672 } else {
b128c09f
BB		 1673 VERIFY(0 == dsl_dataset_hold_obj(dp,
1674 ds->ds_phys->ds_prev_snap_obj, FTAG, &ds_prev));
34dc7c2f
BB		 1675 }
1676 after_branch_point =
1677 (ds_prev->ds_phys->ds_next_snap_obj != obj);
1678
1679 dmu_buf_will_dirty(ds_prev->ds_dbuf, tx);
b128c09f
BB		 1680 if (after_branch_point &&
1681 ds_prev->ds_phys->ds_next_clones_obj != 0) {
428870ff 1682 remove_from_next_clones(ds_prev, obj, tx);
b128c09f
BB		 1683 if (ds->ds_phys->ds_next_snap_obj != 0) {
1684 VERIFY(0 == zap_add_int(mos,
1685 ds_prev->ds_phys->ds_next_clones_obj,
1686 ds->ds_phys->ds_next_snap_obj, tx));
1687 }
1688 }
34dc7c2f
BB		 1689 if (after_branch_point &&
1690 ds->ds_phys->ds_next_snap_obj == 0) {
1691 /* This clone is toast. */
1692 ASSERT(ds_prev->ds_phys->ds_num_children > 1);
1693 ds_prev->ds_phys->ds_num_children--;
45d1cae3
BB		 1694
1695 /*
1696 * If the clone's origin has no other clones, no
1697 * user holds, and has been marked for deferred
1698 * deletion, then we should have done the necessary
1699 * destroy setup for it.
1700 */
1701 if (ds_prev->ds_phys->ds_num_children == 1 &&
1702 ds_prev->ds_userrefs == 0 &&
1703 DS_IS_DEFER_DESTROY(ds_prev)) {
1704 ASSERT3P(dsda->rm_origin, !=, NULL);
1705 } else {
1706 ASSERT3P(dsda->rm_origin, ==, NULL);
1707 }
34dc7c2f
BB		 1708 } else if (!after_branch_point) {
1709 ds_prev->ds_phys->ds_next_snap_obj =
1710 ds->ds_phys->ds_next_snap_obj;
1711 }
1712 }
1713
428870ff 1714 if (dsl_dataset_is_snapshot(ds)) {
34dc7c2f 1715 dsl_dataset_t *ds_next;
34dc7c2f 1716 uint64_t old_unique;
428870ff 1717 uint64_t used = 0, comp = 0, uncomp = 0;
34dc7c2f 1718
b128c09f
BB		 1719 VERIFY(0 == dsl_dataset_hold_obj(dp,
1720 ds->ds_phys->ds_next_snap_obj, FTAG, &ds_next));
34dc7c2f
BB		 1721 ASSERT3U(ds_next->ds_phys->ds_prev_snap_obj, ==, obj);
1722
428870ff 1723 old_unique = ds_next->ds_phys->ds_unique_bytes;
34dc7c2f
BB		 1724
1725 dmu_buf_will_dirty(ds_next->ds_dbuf, tx);
1726 ds_next->ds_phys->ds_prev_snap_obj =
1727 ds->ds_phys->ds_prev_snap_obj;
1728 ds_next->ds_phys->ds_prev_snap_txg =
1729 ds->ds_phys->ds_prev_snap_txg;
1730 ASSERT3U(ds->ds_phys->ds_prev_snap_txg, ==,
1731 ds_prev ? ds_prev->ds_phys->ds_creation_txg : 0);
1732
34dc7c2f 1733
428870ff
BB		 1734 if (ds_next->ds_deadlist.dl_oldfmt) {
1735 process_old_deadlist(ds, ds_prev, ds_next,
1736 after_branch_point, tx);
1737 } else {
1738 /* Adjust prev's unique space. */
1739 if (ds_prev && !after_branch_point) {
1740 dsl_deadlist_space_range(&ds_next->ds_deadlist,
1741 ds_prev->ds_phys->ds_prev_snap_txg,
1742 ds->ds_phys->ds_prev_snap_txg,
1743 &used, &comp, &uncomp);
1744 ds_prev->ds_phys->ds_unique_bytes += used;
1745 }
b128c09f 1746
428870ff
BB		 1747 /* Adjust snapused. */
1748 dsl_deadlist_space_range(&ds_next->ds_deadlist,
1749 ds->ds_phys->ds_prev_snap_txg, UINT64_MAX,
1750 &used, &comp, &uncomp);
1751 dsl_dir_diduse_space(ds->ds_dir, DD_USED_SNAP,
1752 -used, -comp, -uncomp, tx);
1753
1754 /* Move blocks to be freed to pool's free list. */
1755 dsl_deadlist_move_bpobj(&ds_next->ds_deadlist,
1756 &dp->dp_free_bpobj, ds->ds_phys->ds_prev_snap_txg,
1757 tx);
1758 dsl_dir_diduse_space(tx->tx_pool->dp_free_dir,
1759 DD_USED_HEAD, used, comp, uncomp, tx);
1760 dsl_dir_dirty(tx->tx_pool->dp_free_dir, tx);
1761
1762 /* Merge our deadlist into next's and free it. */
1763 dsl_deadlist_merge(&ds_next->ds_deadlist,
1764 ds->ds_phys->ds_deadlist_obj, tx);
1765 }
1766 dsl_deadlist_close(&ds->ds_deadlist);
1767 dsl_deadlist_free(mos, ds->ds_phys->ds_deadlist_obj, tx);
b128c09f 1768
428870ff
BB		 1769 /* Collapse range in clone heads */
1770 dsl_dataset_remove_clones_key(ds,
1771 ds->ds_phys->ds_creation_txg, tx);
34dc7c2f 1772
428870ff
BB		 1773 if (dsl_dataset_is_snapshot(ds_next)) {
1774 dsl_dataset_t *ds_nextnext;
34dc7c2f 1775
34dc7c2f
BB		 1776 /*
1777 * Update next's unique to include blocks which
1778 * were previously shared by only this snapshot
1779 * and it. Those blocks will be born after the
1780 * prev snap and before this snap, and will have
1781 * died after the next snap and before the one
1782 * after that (ie. be on the snap after next's
1783 * deadlist).
34dc7c2f 1784 */
b128c09f
BB		 1785 VERIFY(0 == dsl_dataset_hold_obj(dp,
1786 ds_next->ds_phys->ds_next_snap_obj,
428870ff
BB		 1787 FTAG, &ds_nextnext));
1788 dsl_deadlist_space_range(&ds_nextnext->ds_deadlist,
b128c09f 1789 ds->ds_phys->ds_prev_snap_txg,
428870ff
BB		 1790 ds->ds_phys->ds_creation_txg,
1791 &used, &comp, &uncomp);
1792 ds_next->ds_phys->ds_unique_bytes += used;
1793 dsl_dataset_rele(ds_nextnext, FTAG);
34dc7c2f 1794 ASSERT3P(ds_next->ds_prev, ==, NULL);
428870ff
BB		 1795
1796 /* Collapse range in this head. */
1797 dsl_dataset_t *hds;
1798 VERIFY3U(0, ==, dsl_dataset_hold_obj(dp,
1799 ds->ds_dir->dd_phys->dd_head_dataset_obj,
1800 FTAG, &hds));
1801 dsl_deadlist_remove_key(&hds->ds_deadlist,
1802 ds->ds_phys->ds_creation_txg, tx);
1803 dsl_dataset_rele(hds, FTAG);
1804
34dc7c2f
BB		 1805 } else {
1806 ASSERT3P(ds_next->ds_prev, ==, ds);
b128c09f
BB		 1807 dsl_dataset_drop_ref(ds_next->ds_prev, ds_next);
1808 ds_next->ds_prev = NULL;
34dc7c2f 1809 if (ds_prev) {
b128c09f
BB		 1810 VERIFY(0 == dsl_dataset_get_ref(dp,
1811 ds->ds_phys->ds_prev_snap_obj,
1812 ds_next, &ds_next->ds_prev));
34dc7c2f
BB		 1813 }
1814
1815 dsl_dataset_recalc_head_uniq(ds_next);
1816
1817 /*
1818 * Reduce the amount of our unconsmed refreservation
1819 * being charged to our parent by the amount of
1820 * new unique data we have gained.
1821 */
1822 if (old_unique < ds_next->ds_reserved) {
1823 int64_t mrsdelta;
1824 uint64_t new_unique =
1825 ds_next->ds_phys->ds_unique_bytes;
1826
1827 ASSERT(old_unique <= new_unique);
1828 mrsdelta = MIN(new_unique - old_unique,
1829 ds_next->ds_reserved - old_unique);
b128c09f
BB		 1830 dsl_dir_diduse_space(ds->ds_dir,
1831 DD_USED_REFRSRV, -mrsdelta, 0, 0, tx);
34dc7c2f
BB		 1832 }
1833 }
b128c09f 1834 dsl_dataset_rele(ds_next, FTAG);
34dc7c2f
BB		 1835 } else {
1836 /*
1837 * There's no next snapshot, so this is a head dataset.
1838 * Destroy the deadlist. Unless it's a clone, the
1839 * deadlist should be empty. (If it's a clone, it's
1840 * safe to ignore the deadlist contents.)
1841 */
1842 struct killarg ka;
1843
428870ff
BB		 1844 dsl_deadlist_close(&ds->ds_deadlist);
1845 dsl_deadlist_free(mos, ds->ds_phys->ds_deadlist_obj, tx);
34dc7c2f
BB		 1846 ds->ds_phys->ds_deadlist_obj = 0;
1847
1848 /*
1849 * Free everything that we point to (that's born after
1850 * the previous snapshot, if we are a clone)
1851 *
b128c09f
BB		 1852 * NB: this should be very quick, because we already
1853 * freed all the objects in open context.
34dc7c2f 1854 */
b128c09f 1855 ka.ds = ds;
34dc7c2f 1856 ka.tx = tx;
b128c09f
BB		 1857 err = traverse_dataset(ds, ds->ds_phys->ds_prev_snap_txg,
1858 TRAVERSE_POST, kill_blkptr, &ka);
34dc7c2f 1859 ASSERT3U(err, ==, 0);
9babb374 1860 ASSERT(!DS_UNIQUE_IS_ACCURATE(ds) ||
b128c09f 1861 ds->ds_phys->ds_unique_bytes == 0);
34dc7c2f 1862
428870ff
BB		 1863 if (ds->ds_prev != NULL) {
1864 if (spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) {
1865 VERIFY3U(0, ==, zap_remove_int(mos,
1866 ds->ds_prev->ds_dir->dd_phys->dd_clones,
1867 ds->ds_object, tx));
1868 }
1869 dsl_dataset_rele(ds->ds_prev, ds);
1870 ds->ds_prev = ds_prev = NULL;
1871 }
1872 }
34dc7c2f 1873
572e2857
BB		 1874 /*
1875 * This must be done after the dsl_traverse(), because it will
1876 * re-open the objset.
1877 */
1878 if (ds->ds_objset) {
1879 dmu_objset_evict(ds->ds_objset);
1880 ds->ds_objset = NULL;
1881 }
1882
34dc7c2f 1883 if (ds->ds_dir->dd_phys->dd_head_dataset_obj == ds->ds_object) {
b128c09f 1884 /* Erase the link in the dir */
34dc7c2f
BB		 1885 dmu_buf_will_dirty(ds->ds_dir->dd_dbuf, tx);
1886 ds->ds_dir->dd_phys->dd_head_dataset_obj = 0;
b128c09f
BB		 1887 ASSERT(ds->ds_phys->ds_snapnames_zapobj != 0);
1888 err = zap_destroy(mos, ds->ds_phys->ds_snapnames_zapobj, tx);
1889 ASSERT(err == 0);
34dc7c2f
BB		 1890 } else {
1891 /* remove from snapshot namespace */
1892 dsl_dataset_t *ds_head;
b128c09f
BB		 1893 ASSERT(ds->ds_phys->ds_snapnames_zapobj == 0);
1894 VERIFY(0 == dsl_dataset_hold_obj(dp,
1895 ds->ds_dir->dd_phys->dd_head_dataset_obj, FTAG, &ds_head));
34dc7c2f
BB		 1896 VERIFY(0 == dsl_dataset_get_snapname(ds));
1897#ifdef ZFS_DEBUG
1898 {
1899 uint64_t val;
1900
b128c09f 1901 err = dsl_dataset_snap_lookup(ds_head,
34dc7c2f
BB		 1902 ds->ds_snapname, &val);
1903 ASSERT3U(err, ==, 0);
1904 ASSERT3U(val, ==, obj);
1905 }
1906#endif
b128c09f 1907 err = dsl_dataset_snap_remove(ds_head, ds->ds_snapname, tx);
34dc7c2f 1908 ASSERT(err == 0);
b128c09f 1909 dsl_dataset_rele(ds_head, FTAG);
34dc7c2f
BB		 1910 }
1911
1912 if (ds_prev && ds->ds_prev != ds_prev)
b128c09f 1913 dsl_dataset_rele(ds_prev, FTAG);
34dc7c2f
BB		 1914
1915 spa_prop_clear_bootfs(dp->dp_spa, ds->ds_object, tx);
428870ff
BB		 1916 spa_history_log_internal(LOG_DS_DESTROY, dp->dp_spa, tx,
1917 "dataset = %llu", ds->ds_object);
34dc7c2f 1918
b128c09f
BB		 1919 if (ds->ds_phys->ds_next_clones_obj != 0) {
1920 uint64_t count;
1921 ASSERT(0 == zap_count(mos,
1922 ds->ds_phys->ds_next_clones_obj, &count) && count == 0);
1923 VERIFY(0 == dmu_object_free(mos,
1924 ds->ds_phys->ds_next_clones_obj, tx));
1925 }
1926 if (ds->ds_phys->ds_props_obj != 0)
1927 VERIFY(0 == zap_destroy(mos, ds->ds_phys->ds_props_obj, tx));
45d1cae3
BB		 1928 if (ds->ds_phys->ds_userrefs_obj != 0)
1929 VERIFY(0 == zap_destroy(mos, ds->ds_phys->ds_userrefs_obj, tx));
b128c09f
BB		 1930 dsl_dir_close(ds->ds_dir, ds);
1931 ds->ds_dir = NULL;
1932 dsl_dataset_drain_refs(ds, tag);
34dc7c2f 1933 VERIFY(0 == dmu_object_free(mos, obj, tx));
45d1cae3
BB		 1934
1935 if (dsda->rm_origin) {
1936 /*
1937 * Remove the origin of the clone we just destroyed.
1938 */
45d1cae3
BB		 1939 struct dsl_ds_destroyarg ndsda = {0};
1940
428870ff
BB		 1941 ndsda.ds = dsda->rm_origin;
1942 dsl_dataset_destroy_sync(&ndsda, tag, tx);
45d1cae3 1943 }
34dc7c2f
BB		 1944}
1945
1946static int
1947dsl_dataset_snapshot_reserve_space(dsl_dataset_t *ds, dmu_tx_t *tx)
1948{
1949 uint64_t asize;
1950
1951 if (!dmu_tx_is_syncing(tx))
1952 return (0);
1953
1954 /*
1955 * If there's an fs-only reservation, any blocks that might become
1956 * owned by the snapshot dataset must be accommodated by space
1957 * outside of the reservation.
1958 */
428870ff
BB		 1959 ASSERT(ds->ds_reserved == 0 || DS_UNIQUE_IS_ACCURATE(ds));
1960 asize = MIN(ds->ds_phys->ds_unique_bytes, ds->ds_reserved);
572e2857 1961 if (asize > dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE))
34dc7c2f
BB		 1962 return (ENOSPC);
1963
1964 /*
1965 * Propogate any reserved space for this snapshot to other
1966 * snapshot checks in this sync group.
1967 */
1968 if (asize > 0)
1969 dsl_dir_willuse_space(ds->ds_dir, asize, tx);
1970
1971 return (0);
1972}
1973
34dc7c2f
BB		 1974int
1975dsl_dataset_snapshot_check(void *arg1, void *arg2, dmu_tx_t *tx)
1976{
1977 dsl_dataset_t *ds = arg1;
1978 const char *snapname = arg2;
34dc7c2f
BB		 1979 int err;
1980 uint64_t value;
1981
1982 /*
1983 * We don't allow multiple snapshots of the same txg. If there
1984 * is already one, try again.
1985 */
1986 if (ds->ds_phys->ds_prev_snap_txg >= tx->tx_txg)
1987 return (EAGAIN);
1988
1989 /*
1990 * Check for conflicting name snapshot name.
1991 */
b128c09f 1992 err = dsl_dataset_snap_lookup(ds, snapname, &value);
34dc7c2f
BB		 1993 if (err == 0)
1994 return (EEXIST);
1995 if (err != ENOENT)
1996 return (err);
1997
1998 /*
1999 * Check that the dataset's name is not too long. Name consists
2000 * of the dataset's length + 1 for the @-sign + snapshot name's length
2001 */
2002 if (dsl_dataset_namelen(ds) + 1 + strlen(snapname) >= MAXNAMELEN)
2003 return (ENAMETOOLONG);
2004
2005 err = dsl_dataset_snapshot_reserve_space(ds, tx);
2006 if (err)
2007 return (err);
2008
2009 ds->ds_trysnap_txg = tx->tx_txg;
2010 return (0);
2011}
2012
2013void
428870ff 2014dsl_dataset_snapshot_sync(void *arg1, void *arg2, dmu_tx_t *tx)
34dc7c2f
BB		 2015{
2016 dsl_dataset_t *ds = arg1;
2017 const char *snapname = arg2;
2018 dsl_pool_t *dp = ds->ds_dir->dd_pool;
2019 dmu_buf_t *dbuf;
2020 dsl_dataset_phys_t *dsphys;
b128c09f 2021 uint64_t dsobj, crtxg;
34dc7c2f
BB		 2022 objset_t *mos = dp->dp_meta_objset;
2023 int err;
2024
34dc7c2f
BB		 2025 ASSERT(RW_WRITE_HELD(&dp->dp_config_rwlock));
2026
b128c09f
BB		 2027 /*
2028 * The origin's ds_creation_txg has to be < TXG_INITIAL
2029 */
2030 if (strcmp(snapname, ORIGIN_DIR_NAME) == 0)
2031 crtxg = 1;
2032 else
2033 crtxg = tx->tx_txg;
2034
34dc7c2f
BB		 2035 dsobj = dmu_object_alloc(mos, DMU_OT_DSL_DATASET, 0,
2036 DMU_OT_DSL_DATASET, sizeof (dsl_dataset_phys_t), tx);
2037 VERIFY(0 == dmu_bonus_hold(mos, dsobj, FTAG, &dbuf));
2038 dmu_buf_will_dirty(dbuf, tx);
2039 dsphys = dbuf->db_data;
b128c09f 2040 bzero(dsphys, sizeof (dsl_dataset_phys_t));
34dc7c2f
BB		 2041 dsphys->ds_dir_obj = ds->ds_dir->dd_object;
2042 dsphys->ds_fsid_guid = unique_create();
2043 (void) random_get_pseudo_bytes((void*)&dsphys->ds_guid,
2044 sizeof (dsphys->ds_guid));
2045 dsphys->ds_prev_snap_obj = ds->ds_phys->ds_prev_snap_obj;
2046 dsphys->ds_prev_snap_txg = ds->ds_phys->ds_prev_snap_txg;
2047 dsphys->ds_next_snap_obj = ds->ds_object;
2048 dsphys->ds_num_children = 1;
2049 dsphys->ds_creation_time = gethrestime_sec();
b128c09f 2050 dsphys->ds_creation_txg = crtxg;
34dc7c2f
BB		 2051 dsphys->ds_deadlist_obj = ds->ds_phys->ds_deadlist_obj;
2052 dsphys->ds_used_bytes = ds->ds_phys->ds_used_bytes;
2053 dsphys->ds_compressed_bytes = ds->ds_phys->ds_compressed_bytes;
2054 dsphys->ds_uncompressed_bytes = ds->ds_phys->ds_uncompressed_bytes;
2055 dsphys->ds_flags = ds->ds_phys->ds_flags;
2056 dsphys->ds_bp = ds->ds_phys->ds_bp;
2057 dmu_buf_rele(dbuf, FTAG);
2058
2059 ASSERT3U(ds->ds_prev != 0, ==, ds->ds_phys->ds_prev_snap_obj != 0);
2060 if (ds->ds_prev) {
b128c09f
BB		 2061 uint64_t next_clones_obj =
2062 ds->ds_prev->ds_phys->ds_next_clones_obj;
34dc7c2f
BB		 2063 ASSERT(ds->ds_prev->ds_phys->ds_next_snap_obj ==
2064 ds->ds_object ||
2065 ds->ds_prev->ds_phys->ds_num_children > 1);
2066 if (ds->ds_prev->ds_phys->ds_next_snap_obj == ds->ds_object) {
2067 dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx);
2068 ASSERT3U(ds->ds_phys->ds_prev_snap_txg, ==,
2069 ds->ds_prev->ds_phys->ds_creation_txg);
2070 ds->ds_prev->ds_phys->ds_next_snap_obj = dsobj;
b128c09f 2071 } else if (next_clones_obj != 0) {
428870ff
BB		 2072 remove_from_next_clones(ds->ds_prev,
2073 dsphys->ds_next_snap_obj, tx);
b128c09f
BB		 2074 VERIFY3U(0, ==, zap_add_int(mos,
2075 next_clones_obj, dsobj, tx));
34dc7c2f
BB		 2076 }
2077 }
2078
2079 /*
2080 * If we have a reference-reservation on this dataset, we will
2081 * need to increase the amount of refreservation being charged
2082 * since our unique space is going to zero.
2083 */
2084 if (ds->ds_reserved) {
428870ff
BB		 2085 int64_t delta;
2086 ASSERT(DS_UNIQUE_IS_ACCURATE(ds));
2087 delta = MIN(ds->ds_phys->ds_unique_bytes, ds->ds_reserved);
b128c09f 2088 dsl_dir_diduse_space(ds->ds_dir, DD_USED_REFRSRV,
428870ff 2089 delta, 0, 0, tx);
34dc7c2f
BB		 2090 }
2091
34dc7c2f 2092 dmu_buf_will_dirty(ds->ds_dbuf, tx);
428870ff
BB		 2093 zfs_dbgmsg("taking snapshot %s@%s/%llu; newkey=%llu",
2094 ds->ds_dir->dd_myname, snapname, dsobj,
2095 ds->ds_phys->ds_prev_snap_txg);
2096 ds->ds_phys->ds_deadlist_obj = dsl_deadlist_clone(&ds->ds_deadlist,
2097 UINT64_MAX, ds->ds_phys->ds_prev_snap_obj, tx);
2098 dsl_deadlist_close(&ds->ds_deadlist);
2099 dsl_deadlist_open(&ds->ds_deadlist, mos, ds->ds_phys->ds_deadlist_obj);
2100 dsl_deadlist_add_key(&ds->ds_deadlist,
2101 ds->ds_phys->ds_prev_snap_txg, tx);
2102
34dc7c2f
BB		 2103 ASSERT3U(ds->ds_phys->ds_prev_snap_txg, <, tx->tx_txg);
2104 ds->ds_phys->ds_prev_snap_obj = dsobj;
b128c09f 2105 ds->ds_phys->ds_prev_snap_txg = crtxg;
34dc7c2f
BB		 2106 ds->ds_phys->ds_unique_bytes = 0;
2107 if (spa_version(dp->dp_spa) >= SPA_VERSION_UNIQUE_ACCURATE)
2108 ds->ds_phys->ds_flags |= DS_FLAG_UNIQUE_ACCURATE;
34dc7c2f 2109
34dc7c2f
BB		 2110 err = zap_add(mos, ds->ds_phys->ds_snapnames_zapobj,
2111 snapname, 8, 1, &dsobj, tx);
2112 ASSERT(err == 0);
2113
2114 if (ds->ds_prev)
b128c09f
BB		 2115 dsl_dataset_drop_ref(ds->ds_prev, ds);
2116 VERIFY(0 == dsl_dataset_get_ref(dp,
2117 ds->ds_phys->ds_prev_snap_obj, ds, &ds->ds_prev));
2118
428870ff
BB		 2119 dsl_scan_ds_snapshotted(ds, tx);
2120
2121 dsl_dir_snap_cmtime_update(ds->ds_dir);
34dc7c2f 2122
428870ff 2123 spa_history_log_internal(LOG_DS_SNAPSHOT, dp->dp_spa, tx,
34dc7c2f
BB		 2124 "dataset = %llu", dsobj);
2125}
2126
2127void
2128dsl_dataset_sync(dsl_dataset_t *ds, zio_t *zio, dmu_tx_t *tx)
2129{
2130 ASSERT(dmu_tx_is_syncing(tx));
428870ff 2131 ASSERT(ds->ds_objset != NULL);
34dc7c2f
BB		 2132 ASSERT(ds->ds_phys->ds_next_snap_obj == 0);
2133
2134 /*
2135 * in case we had to change ds_fsid_guid when we opened it,
2136 * sync it out now.
2137 */
2138 dmu_buf_will_dirty(ds->ds_dbuf, tx);
2139 ds->ds_phys->ds_fsid_guid = ds->ds_fsid_guid;
2140
2141 dsl_dir_dirty(ds->ds_dir, tx);
428870ff 2142 dmu_objset_sync(ds->ds_objset, zio, tx);
34dc7c2f
BB		 2143}
2144
2145void
2146dsl_dataset_stats(dsl_dataset_t *ds, nvlist_t *nv)
2147{
2148 uint64_t refd, avail, uobjs, aobjs;
2149
2150 dsl_dir_stats(ds->ds_dir, nv);
2151
2152 dsl_dataset_space(ds, &refd, &avail, &uobjs, &aobjs);
2153 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_AVAILABLE, avail);
2154 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFERENCED, refd);
2155
2156 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATION,
2157 ds->ds_phys->ds_creation_time);
2158 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_CREATETXG,
2159 ds->ds_phys->ds_creation_txg);
2160 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFQUOTA,
2161 ds->ds_quota);
2162 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_REFRESERVATION,
2163 ds->ds_reserved);
b128c09f
BB		 2164 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_GUID,
2165 ds->ds_phys->ds_guid);
428870ff
BB		 2166 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_UNIQUE,
2167 ds->ds_phys->ds_unique_bytes);
2168 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_OBJSETID,
2169 ds->ds_object);
2170 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USERREFS,
2171 ds->ds_userrefs);
45d1cae3
BB		 2172 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_DEFER_DESTROY,
2173 DS_IS_DEFER_DESTROY(ds) ? 1 : 0);
34dc7c2f
BB		 2174
2175 if (ds->ds_phys->ds_next_snap_obj) {
2176 /*
2177 * This is a snapshot; override the dd's space used with
2178 * our unique space and compression ratio.
2179 */
2180 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USED,
2181 ds->ds_phys->ds_unique_bytes);
2182 dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_COMPRESSRATIO,
2183 ds->ds_phys->ds_compressed_bytes == 0 ? 100 :
2184 (ds->ds_phys->ds_uncompressed_bytes * 100 /
2185 ds->ds_phys->ds_compressed_bytes));
2186 }
2187}
2188
2189void
2190dsl_dataset_fast_stat(dsl_dataset_t *ds, dmu_objset_stats_t *stat)
2191{
2192 stat->dds_creation_txg = ds->ds_phys->ds_creation_txg;
2193 stat->dds_inconsistent = ds->ds_phys->ds_flags & DS_FLAG_INCONSISTENT;
2194 stat->dds_guid = ds->ds_phys->ds_guid;
2195 if (ds->ds_phys->ds_next_snap_obj) {
2196 stat->dds_is_snapshot = B_TRUE;
2197 stat->dds_num_clones = ds->ds_phys->ds_num_children - 1;
fb5f0bc8
BB		 2198 } else {
2199 stat->dds_is_snapshot = B_FALSE;
2200 stat->dds_num_clones = 0;
34dc7c2f
BB		 2201 }
2202
2203 /* clone origin is really a dsl_dir thing... */
2204 rw_enter(&ds->ds_dir->dd_pool->dp_config_rwlock, RW_READER);
b128c09f 2205 if (dsl_dir_is_clone(ds->ds_dir)) {
34dc7c2f
BB		 2206 dsl_dataset_t *ods;
2207
b128c09f
BB		 2208 VERIFY(0 == dsl_dataset_get_ref(ds->ds_dir->dd_pool,
2209 ds->ds_dir->dd_phys->dd_origin_obj, FTAG, &ods));
34dc7c2f 2210 dsl_dataset_name(ods, stat->dds_origin);
b128c09f 2211 dsl_dataset_drop_ref(ods, FTAG);
fb5f0bc8
BB		 2212 } else {
2213 stat->dds_origin[0] = '\0';
34dc7c2f
BB		 2214 }
2215 rw_exit(&ds->ds_dir->dd_pool->dp_config_rwlock);
2216}
2217
2218uint64_t
2219dsl_dataset_fsid_guid(dsl_dataset_t *ds)
2220{
2221 return (ds->ds_fsid_guid);
2222}
2223
2224void
2225dsl_dataset_space(dsl_dataset_t *ds,
2226 uint64_t *refdbytesp, uint64_t *availbytesp,
2227 uint64_t *usedobjsp, uint64_t *availobjsp)
2228{
2229 *refdbytesp = ds->ds_phys->ds_used_bytes;
2230 *availbytesp = dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE);
2231 if (ds->ds_reserved > ds->ds_phys->ds_unique_bytes)
2232 *availbytesp += ds->ds_reserved - ds->ds_phys->ds_unique_bytes;
2233 if (ds->ds_quota != 0) {
2234 /*
2235 * Adjust available bytes according to refquota
2236 */
2237 if (*refdbytesp < ds->ds_quota)
2238 *availbytesp = MIN(*availbytesp,
2239 ds->ds_quota - *refdbytesp);
2240 else
2241 *availbytesp = 0;
2242 }
2243 *usedobjsp = ds->ds_phys->ds_bp.blk_fill;
2244 *availobjsp = DN_MAX_OBJECT - *usedobjsp;
2245}
2246
2247boolean_t
2248dsl_dataset_modified_since_lastsnap(dsl_dataset_t *ds)
2249{
2250 dsl_pool_t *dp = ds->ds_dir->dd_pool;
2251
2252 ASSERT(RW_LOCK_HELD(&dp->dp_config_rwlock) ||
2253 dsl_pool_sync_context(dp));
2254 if (ds->ds_prev == NULL)
2255 return (B_FALSE);
2256 if (ds->ds_phys->ds_bp.blk_birth >
572e2857
BB		 2257 ds->ds_prev->ds_phys->ds_creation_txg) {
2258 objset_t *os, *os_prev;
2259 /*
2260 * It may be that only the ZIL differs, because it was
2261 * reset in the head. Don't count that as being
2262 * modified.
2263 */
2264 if (dmu_objset_from_ds(ds, &os) != 0)
2265 return (B_TRUE);
2266 if (dmu_objset_from_ds(ds->ds_prev, &os_prev) != 0)
2267 return (B_TRUE);
2268 return (bcmp(&os->os_phys->os_meta_dnode,
2269 &os_prev->os_phys->os_meta_dnode,
2270 sizeof (os->os_phys->os_meta_dnode)) != 0);
2271 }
34dc7c2f
BB		 2272 return (B_FALSE);
2273}
2274
2275/* ARGSUSED */
2276static int
2277dsl_dataset_snapshot_rename_check(void *arg1, void *arg2, dmu_tx_t *tx)
2278{
2279 dsl_dataset_t *ds = arg1;
2280 char *newsnapname = arg2;
2281 dsl_dir_t *dd = ds->ds_dir;
34dc7c2f
BB		 2282 dsl_dataset_t *hds;
2283 uint64_t val;
2284 int err;
2285
b128c09f
BB		 2286 err = dsl_dataset_hold_obj(dd->dd_pool,
2287 dd->dd_phys->dd_head_dataset_obj, FTAG, &hds);
34dc7c2f
BB		 2288 if (err)
2289 return (err);
2290
2291 /* new name better not be in use */
b128c09f
BB		 2292 err = dsl_dataset_snap_lookup(hds, newsnapname, &val);
2293 dsl_dataset_rele(hds, FTAG);
34dc7c2f
BB		 2294
2295 if (err == 0)
2296 err = EEXIST;
2297 else if (err == ENOENT)
2298 err = 0;
2299
2300 /* dataset name + 1 for the "@" + the new snapshot name must fit */
2301 if (dsl_dir_namelen(ds->ds_dir) + 1 + strlen(newsnapname) >= MAXNAMELEN)
2302 err = ENAMETOOLONG;
2303
2304 return (err);
2305}
2306
2307static void
428870ff 2308dsl_dataset_snapshot_rename_sync(void *arg1, void *arg2, dmu_tx_t *tx)
34dc7c2f
BB		 2309{
2310 dsl_dataset_t *ds = arg1;
2311 const char *newsnapname = arg2;
2312 dsl_dir_t *dd = ds->ds_dir;
2313 objset_t *mos = dd->dd_pool->dp_meta_objset;
2314 dsl_dataset_t *hds;
2315 int err;
2316
2317 ASSERT(ds->ds_phys->ds_next_snap_obj != 0);
2318
b128c09f
BB		 2319 VERIFY(0 == dsl_dataset_hold_obj(dd->dd_pool,
2320 dd->dd_phys->dd_head_dataset_obj, FTAG, &hds));
34dc7c2f
BB		 2321
2322 VERIFY(0 == dsl_dataset_get_snapname(ds));
b128c09f 2323 err = dsl_dataset_snap_remove(hds, ds->ds_snapname, tx);
34dc7c2f
BB		 2324 ASSERT3U(err, ==, 0);
2325 mutex_enter(&ds->ds_lock);
2326 (void) strcpy(ds->ds_snapname, newsnapname);
2327 mutex_exit(&ds->ds_lock);
2328 err = zap_add(mos, hds->ds_phys->ds_snapnames_zapobj,
2329 ds->ds_snapname, 8, 1, &ds->ds_object, tx);
2330 ASSERT3U(err, ==, 0);
2331
428870ff
BB		 2332 spa_history_log_internal(LOG_DS_RENAME, dd->dd_pool->dp_spa, tx,
2333 "dataset = %llu", ds->ds_object);
b128c09f 2334 dsl_dataset_rele(hds, FTAG);
34dc7c2f
BB		 2335}
2336
2337struct renamesnaparg {
2338 dsl_sync_task_group_t *dstg;
2339 char failed[MAXPATHLEN];
2340 char *oldsnap;
2341 char *newsnap;
2342};
2343
2344static int
428870ff 2345dsl_snapshot_rename_one(const char *name, void *arg)
34dc7c2f
BB		 2346{
2347 struct renamesnaparg *ra = arg;
2348 dsl_dataset_t *ds = NULL;
428870ff 2349 char *snapname;
34dc7c2f
BB		 2350 int err;
2351
428870ff
BB		 2352 snapname = kmem_asprintf("%s@%s", name, ra->oldsnap);
2353 (void) strlcpy(ra->failed, snapname, sizeof (ra->failed));
34dc7c2f
BB		 2354
2355 /*
2356 * For recursive snapshot renames the parent won't be changing
2357 * so we just pass name for both the to/from argument.
2358 */
428870ff
BB		 2359 err = zfs_secpolicy_rename_perms(snapname, snapname, CRED());
2360 if (err != 0) {
2361 strfree(snapname);
2362 return (err == ENOENT ? 0 : err);
34dc7c2f
BB		 2363 }
2364
2365#ifdef _KERNEL
b128c09f
BB		 2366 /*
2367 * For all filesystems undergoing rename, we'll need to unmount it.
2368 */
428870ff 2369 (void) zfs_unmount_snap(snapname, NULL);
34dc7c2f 2370#endif
428870ff
BB		 2371 err = dsl_dataset_hold(snapname, ra->dstg, &ds);
2372 strfree(snapname);
2373 if (err != 0)
2374 return (err == ENOENT ? 0 : err);
34dc7c2f
BB		 2375
2376 dsl_sync_task_create(ra->dstg, dsl_dataset_snapshot_rename_check,
2377 dsl_dataset_snapshot_rename_sync, ds, ra->newsnap, 0);
2378
2379 return (0);
2380}
2381
2382static int
2383dsl_recursive_rename(char *oldname, const char *newname)
2384{
2385 int err;
2386 struct renamesnaparg *ra;
2387 dsl_sync_task_t *dst;
2388 spa_t *spa;
2389 char *cp, *fsname = spa_strdup(oldname);
428870ff 2390 int len = strlen(oldname) + 1;
34dc7c2f
BB		 2391
2392 /* truncate the snapshot name to get the fsname */
2393 cp = strchr(fsname, '@');
2394 *cp = '\0';
2395
2396 err = spa_open(fsname, &spa, FTAG);
2397 if (err) {
428870ff 2398 kmem_free(fsname, len);
34dc7c2f
BB		 2399 return (err);
2400 }
2401 ra = kmem_alloc(sizeof (struct renamesnaparg), KM_SLEEP);
2402 ra->dstg = dsl_sync_task_group_create(spa_get_dsl(spa));
2403
2404 ra->oldsnap = strchr(oldname, '@') + 1;
2405 ra->newsnap = strchr(newname, '@') + 1;
2406 *ra->failed = '\0';
2407
2408 err = dmu_objset_find(fsname, dsl_snapshot_rename_one, ra,
2409 DS_FIND_CHILDREN);
428870ff 2410 kmem_free(fsname, len);
34dc7c2f
BB		 2411
2412 if (err == 0) {
2413 err = dsl_sync_task_group_wait(ra->dstg);
2414 }
2415
2416 for (dst = list_head(&ra->dstg->dstg_tasks); dst;
2417 dst = list_next(&ra->dstg->dstg_tasks, dst)) {
2418 dsl_dataset_t *ds = dst->dst_arg1;
2419 if (dst->dst_err) {
2420 dsl_dir_name(ds->ds_dir, ra->failed);
428870ff
BB		 2421 (void) strlcat(ra->failed, "@", sizeof (ra->failed));
2422 (void) strlcat(ra->failed, ra->newsnap,
2423 sizeof (ra->failed));
34dc7c2f 2424 }
b128c09f 2425 dsl_dataset_rele(ds, ra->dstg);
34dc7c2f
BB		 2426 }
2427
2428 if (err)
428870ff 2429 (void) strlcpy(oldname, ra->failed, sizeof (ra->failed));
34dc7c2f
BB		 2430
2431 dsl_sync_task_group_destroy(ra->dstg);
2432 kmem_free(ra, sizeof (struct renamesnaparg));
2433 spa_close(spa, FTAG);
2434 return (err);
2435}
2436
2437static int
428870ff 2438dsl_valid_rename(const char *oldname, void *arg)
34dc7c2f
BB		 2439{
2440 int delta = *(int *)arg;
2441
2442 if (strlen(oldname) + delta >= MAXNAMELEN)
2443 return (ENAMETOOLONG);
2444
2445 return (0);
2446}
2447
2448#pragma weak dmu_objset_rename = dsl_dataset_rename
2449int
b128c09f 2450dsl_dataset_rename(char *oldname, const char *newname, boolean_t recursive)
34dc7c2f
BB		 2451{
2452 dsl_dir_t *dd;
2453 dsl_dataset_t *ds;
2454 const char *tail;
2455 int err;
2456
2457 err = dsl_dir_open(oldname, FTAG, &dd, &tail);
2458 if (err)
2459 return (err);
428870ff 2460
34dc7c2f
BB		 2461 if (tail == NULL) {
2462 int delta = strlen(newname) - strlen(oldname);
2463
b128c09f 2464 /* if we're growing, validate child name lengths */
34dc7c2f
BB		 2465 if (delta > 0)
2466 err = dmu_objset_find(oldname, dsl_valid_rename,
2467 &delta, DS_FIND_CHILDREN | DS_FIND_SNAPSHOTS);
2468
428870ff 2469 if (err == 0)
34dc7c2f
BB		 2470 err = dsl_dir_rename(dd, newname);
2471 dsl_dir_close(dd, FTAG);
2472 return (err);
2473 }
428870ff 2474
34dc7c2f 2475 if (tail[0] != '@') {
428870ff 2476 /* the name ended in a nonexistent component */
34dc7c2f
BB		 2477 dsl_dir_close(dd, FTAG);
2478 return (ENOENT);
2479 }
2480
2481 dsl_dir_close(dd, FTAG);
2482
2483 /* new name must be snapshot in same filesystem */
2484 tail = strchr(newname, '@');
2485 if (tail == NULL)
2486 return (EINVAL);
2487 tail++;
2488 if (strncmp(oldname, newname, tail - newname) != 0)
2489 return (EXDEV);
2490
2491 if (recursive) {
2492 err = dsl_recursive_rename(oldname, newname);
2493 } else {
b128c09f 2494 err = dsl_dataset_hold(oldname, FTAG, &ds);
34dc7c2f
BB		 2495 if (err)
2496 return (err);
2497
2498 err = dsl_sync_task_do(ds->ds_dir->dd_pool,
2499 dsl_dataset_snapshot_rename_check,
2500 dsl_dataset_snapshot_rename_sync, ds, (char *)tail, 1);
2501
b128c09f 2502 dsl_dataset_rele(ds, FTAG);
34dc7c2f
BB		 2503 }
2504
2505 return (err);
2506}
2507
b128c09f
BB		 2508struct promotenode {
2509 list_node_t link;
2510 dsl_dataset_t *ds;
2511};
2512
34dc7c2f 2513struct promotearg {
b128c09f 2514 list_t shared_snaps, origin_snaps, clone_snaps;
428870ff 2515 dsl_dataset_t *origin_origin;
b128c09f 2516 uint64_t used, comp, uncomp, unique, cloneusedsnap, originusedsnap;
428870ff 2517 char *err_ds;
34dc7c2f
BB		 2518};
2519
b128c09f 2520static int snaplist_space(list_t *l, uint64_t mintxg, uint64_t *spacep);
428870ff 2521static boolean_t snaplist_unstable(list_t *l);
b128c09f 2522
34dc7c2f
BB		 2523static int
2524dsl_dataset_promote_check(void *arg1, void *arg2, dmu_tx_t *tx)
2525{
2526 dsl_dataset_t *hds = arg1;
2527 struct promotearg *pa = arg2;
b128c09f
BB		 2528 struct promotenode *snap = list_head(&pa->shared_snaps);
2529 dsl_dataset_t *origin_ds = snap->ds;
34dc7c2f 2530 int err;
428870ff 2531 uint64_t unused;
34dc7c2f 2532
b128c09f
BB		 2533 /* Check that it is a real clone */
2534 if (!dsl_dir_is_clone(hds->ds_dir))
34dc7c2f
BB		 2535 return (EINVAL);
2536
2537 /* Since this is so expensive, don't do the preliminary check */
2538 if (!dmu_tx_is_syncing(tx))
2539 return (0);
2540
b128c09f
BB		 2541 if (hds->ds_phys->ds_flags & DS_FLAG_NOPROMOTE)
2542 return (EXDEV);
34dc7c2f
BB		 2543
2544 /* compute origin's new unique space */
b128c09f
BB		 2545 snap = list_tail(&pa->clone_snaps);
2546 ASSERT3U(snap->ds->ds_phys->ds_prev_snap_obj, ==, origin_ds->ds_object);
428870ff
BB		 2547 dsl_deadlist_space_range(&snap->ds->ds_deadlist,
2548 origin_ds->ds_phys->ds_prev_snap_txg, UINT64_MAX,
2549 &pa->unique, &unused, &unused);
34dc7c2f 2550
b128c09f
BB		 2551 /*
2552 * Walk the snapshots that we are moving
2553 *
2554 * Compute space to transfer. Consider the incremental changes
2555 * to used for each snapshot:
2556 * (my used) = (prev's used) + (blocks born) - (blocks killed)
2557 * So each snapshot gave birth to:
2558 * (blocks born) = (my used) - (prev's used) + (blocks killed)
2559 * So a sequence would look like:
2560 * (uN - u(N-1) + kN) + ... + (u1 - u0 + k1) + (u0 - 0 + k0)
2561 * Which simplifies to:
2562 * uN + kN + kN-1 + ... + k1 + k0
2563 * Note however, if we stop before we reach the ORIGIN we get:
2564 * uN + kN + kN-1 + ... + kM - uM-1
2565 */
2566 pa->used = origin_ds->ds_phys->ds_used_bytes;
2567 pa->comp = origin_ds->ds_phys->ds_compressed_bytes;
2568 pa->uncomp = origin_ds->ds_phys->ds_uncompressed_bytes;
2569 for (snap = list_head(&pa->shared_snaps); snap;
2570 snap = list_next(&pa->shared_snaps, snap)) {
34dc7c2f 2571 uint64_t val, dlused, dlcomp, dluncomp;
b128c09f 2572 dsl_dataset_t *ds = snap->ds;
34dc7c2f
BB		 2573
2574 /* Check that the snapshot name does not conflict */
b128c09f
BB		 2575 VERIFY(0 == dsl_dataset_get_snapname(ds));
2576 err = dsl_dataset_snap_lookup(hds, ds->ds_snapname, &val);
428870ff
BB		 2577 if (err == 0) {
2578 err = EEXIST;
2579 goto out;
2580 }
b128c09f 2581 if (err != ENOENT)
428870ff 2582 goto out;
34dc7c2f 2583
b128c09f 2584 /* The very first snapshot does not have a deadlist */
34dc7c2f 2585 if (ds->ds_phys->ds_prev_snap_obj == 0)
b128c09f 2586 continue;
34dc7c2f 2587
428870ff
BB		 2588 dsl_deadlist_space(&ds->ds_deadlist,
2589 &dlused, &dlcomp, &dluncomp);
b128c09f
BB		 2590 pa->used += dlused;
2591 pa->comp += dlcomp;
2592 pa->uncomp += dluncomp;
2593 }
34dc7c2f 2594
b128c09f
BB		 2595 /*
2596 * If we are a clone of a clone then we never reached ORIGIN,
2597 * so we need to subtract out the clone origin's used space.
2598 */
2599 if (pa->origin_origin) {
2600 pa->used -= pa->origin_origin->ds_phys->ds_used_bytes;
2601 pa->comp -= pa->origin_origin->ds_phys->ds_compressed_bytes;
2602 pa->uncomp -= pa->origin_origin->ds_phys->ds_uncompressed_bytes;
34dc7c2f
BB		 2603 }
2604
2605 /* Check that there is enough space here */
b128c09f
BB		 2606 err = dsl_dir_transfer_possible(origin_ds->ds_dir, hds->ds_dir,
2607 pa->used);
2608 if (err)
2609 return (err);
34dc7c2f 2610
b128c09f
BB		 2611 /*
2612 * Compute the amounts of space that will be used by snapshots
2613 * after the promotion (for both origin and clone). For each,
2614 * it is the amount of space that will be on all of their
2615 * deadlists (that was not born before their new origin).
2616 */
2617 if (hds->ds_dir->dd_phys->dd_flags & DD_FLAG_USED_BREAKDOWN) {
2618 uint64_t space;
2619
2620 /*
2621 * Note, typically this will not be a clone of a clone,
428870ff
BB		 2622 * so dd_origin_txg will be < TXG_INITIAL, so
2623 * these snaplist_space() -> dsl_deadlist_space_range()
b128c09f
BB		 2624 * calls will be fast because they do not have to
2625 * iterate over all bps.
2626 */
2627 snap = list_head(&pa->origin_snaps);
2628 err = snaplist_space(&pa->shared_snaps,
428870ff 2629 snap->ds->ds_dir->dd_origin_txg, &pa->cloneusedsnap);
b128c09f
BB		 2630 if (err)
2631 return (err);
2632
2633 err = snaplist_space(&pa->clone_snaps,
428870ff 2634 snap->ds->ds_dir->dd_origin_txg, &space);
b128c09f
BB		 2635 if (err)
2636 return (err);
2637 pa->cloneusedsnap += space;
2638 }
2639 if (origin_ds->ds_dir->dd_phys->dd_flags & DD_FLAG_USED_BREAKDOWN) {
2640 err = snaplist_space(&pa->origin_snaps,
2641 origin_ds->ds_phys->ds_creation_txg, &pa->originusedsnap);
2642 if (err)
2643 return (err);
2644 }
2645
2646 return (0);
428870ff
BB		 2647out:
2648 pa->err_ds = snap->ds->ds_snapname;
2649 return (err);
34dc7c2f
BB		 2650}
2651
2652static void
428870ff 2653dsl_dataset_promote_sync(void *arg1, void *arg2, dmu_tx_t *tx)
34dc7c2f
BB		 2654{
2655 dsl_dataset_t *hds = arg1;
2656 struct promotearg *pa = arg2;
b128c09f
BB		 2657 struct promotenode *snap = list_head(&pa->shared_snaps);
2658 dsl_dataset_t *origin_ds = snap->ds;
2659 dsl_dataset_t *origin_head;
34dc7c2f
BB		 2660 dsl_dir_t *dd = hds->ds_dir;
2661 dsl_pool_t *dp = hds->ds_dir->dd_pool;
2662 dsl_dir_t *odd = NULL;
b128c09f
BB		 2663 uint64_t oldnext_obj;
2664 int64_t delta;
34dc7c2f 2665
34dc7c2f
BB		 2666 ASSERT(0 == (hds->ds_phys->ds_flags & DS_FLAG_NOPROMOTE));
2667
b128c09f
BB		 2668 snap = list_head(&pa->origin_snaps);
2669 origin_head = snap->ds;
2670
34dc7c2f
BB		 2671 /*
2672 * We need to explicitly open odd, since origin_ds's dd will be
2673 * changing.
2674 */
2675 VERIFY(0 == dsl_dir_open_obj(dp, origin_ds->ds_dir->dd_object,
2676 NULL, FTAG, &odd));
2677
b128c09f
BB		 2678 /* change origin's next snap */
2679 dmu_buf_will_dirty(origin_ds->ds_dbuf, tx);
2680 oldnext_obj = origin_ds->ds_phys->ds_next_snap_obj;
2681 snap = list_tail(&pa->clone_snaps);
2682 ASSERT3U(snap->ds->ds_phys->ds_prev_snap_obj, ==, origin_ds->ds_object);
2683 origin_ds->ds_phys->ds_next_snap_obj = snap->ds->ds_object;
2684
2685 /* change the origin's next clone */
2686 if (origin_ds->ds_phys->ds_next_clones_obj) {
428870ff 2687 remove_from_next_clones(origin_ds, snap->ds->ds_object, tx);
b128c09f
BB		 2688 VERIFY3U(0, ==, zap_add_int(dp->dp_meta_objset,
2689 origin_ds->ds_phys->ds_next_clones_obj,
2690 oldnext_obj, tx));
2691 }
2692
2693 /* change origin */
2694 dmu_buf_will_dirty(dd->dd_dbuf, tx);
2695 ASSERT3U(dd->dd_phys->dd_origin_obj, ==, origin_ds->ds_object);
2696 dd->dd_phys->dd_origin_obj = odd->dd_phys->dd_origin_obj;
428870ff 2697 dd->dd_origin_txg = origin_head->ds_dir->dd_origin_txg;
b128c09f
BB		 2698 dmu_buf_will_dirty(odd->dd_dbuf, tx);
2699 odd->dd_phys->dd_origin_obj = origin_ds->ds_object;
428870ff
BB		 2700 origin_head->ds_dir->dd_origin_txg =
2701 origin_ds->ds_phys->ds_creation_txg;
2702
2703 /* change dd_clone entries */
2704 if (spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) {
2705 VERIFY3U(0, ==, zap_remove_int(dp->dp_meta_objset,
2706 odd->dd_phys->dd_clones, hds->ds_object, tx));
2707 VERIFY3U(0, ==, zap_add_int(dp->dp_meta_objset,
2708 pa->origin_origin->ds_dir->dd_phys->dd_clones,
2709 hds->ds_object, tx));
2710
2711 VERIFY3U(0, ==, zap_remove_int(dp->dp_meta_objset,
2712 pa->origin_origin->ds_dir->dd_phys->dd_clones,
2713 origin_head->ds_object, tx));
2714 if (dd->dd_phys->dd_clones == 0) {
2715 dd->dd_phys->dd_clones = zap_create(dp->dp_meta_objset,
2716 DMU_OT_DSL_CLONES, DMU_OT_NONE, 0, tx);
2717 }
2718 VERIFY3U(0, ==, zap_add_int(dp->dp_meta_objset,
2719 dd->dd_phys->dd_clones, origin_head->ds_object, tx));
2720
2721 }
34dc7c2f 2722
b128c09f
BB		 2723 /* move snapshots to this dir */
2724 for (snap = list_head(&pa->shared_snaps); snap;
2725 snap = list_next(&pa->shared_snaps, snap)) {
2726 dsl_dataset_t *ds = snap->ds;
2727
2728 /* unregister props as dsl_dir is changing */
428870ff
BB		 2729 if (ds->ds_objset) {
2730 dmu_objset_evict(ds->ds_objset);
2731 ds->ds_objset = NULL;
b128c09f 2732 }
34dc7c2f 2733 /* move snap name entry */
b128c09f
BB		 2734 VERIFY(0 == dsl_dataset_get_snapname(ds));
2735 VERIFY(0 == dsl_dataset_snap_remove(origin_head,
2736 ds->ds_snapname, tx));
34dc7c2f
BB		 2737 VERIFY(0 == zap_add(dp->dp_meta_objset,
2738 hds->ds_phys->ds_snapnames_zapobj, ds->ds_snapname,
2739 8, 1, &ds->ds_object, tx));
428870ff 2740
34dc7c2f
BB		 2741 /* change containing dsl_dir */
2742 dmu_buf_will_dirty(ds->ds_dbuf, tx);
2743 ASSERT3U(ds->ds_phys->ds_dir_obj, ==, odd->dd_object);
2744 ds->ds_phys->ds_dir_obj = dd->dd_object;
2745 ASSERT3P(ds->ds_dir, ==, odd);
2746 dsl_dir_close(ds->ds_dir, ds);
2747 VERIFY(0 == dsl_dir_open_obj(dp, dd->dd_object,
2748 NULL, ds, &ds->ds_dir));
2749
428870ff
BB		 2750 /* move any clone references */
2751 if (ds->ds_phys->ds_next_clones_obj &&
2752 spa_version(dp->dp_spa) >= SPA_VERSION_DIR_CLONES) {
2753 zap_cursor_t zc;
2754 zap_attribute_t za;
2755
2756 for (zap_cursor_init(&zc, dp->dp_meta_objset,
2757 ds->ds_phys->ds_next_clones_obj);
2758 zap_cursor_retrieve(&zc, &za) == 0;
2759 zap_cursor_advance(&zc)) {
2760 dsl_dataset_t *cnds;
2761 uint64_t o;
2762
2763 if (za.za_first_integer == oldnext_obj) {
2764 /*
2765 * We've already moved the
2766 * origin's reference.
2767 */
2768 continue;
2769 }
2770
2771 VERIFY3U(0, ==, dsl_dataset_hold_obj(dp,
2772 za.za_first_integer, FTAG, &cnds));
2773 o = cnds->ds_dir->dd_phys->dd_head_dataset_obj;
2774
2775 VERIFY3U(zap_remove_int(dp->dp_meta_objset,
2776 odd->dd_phys->dd_clones, o, tx), ==, 0);
2777 VERIFY3U(zap_add_int(dp->dp_meta_objset,
2778 dd->dd_phys->dd_clones, o, tx), ==, 0);
2779 dsl_dataset_rele(cnds, FTAG);
2780 }
2781 zap_cursor_fini(&zc);
2782 }
2783
34dc7c2f 2784 ASSERT3U(dsl_prop_numcb(ds), ==, 0);
34dc7c2f 2785 }
34dc7c2f 2786
b128c09f
BB		 2787 /*
2788 * Change space accounting.
2789 * Note, pa->*usedsnap and dd_used_breakdown[SNAP] will either
2790 * both be valid, or both be 0 (resulting in delta == 0). This
2791 * is true for each of {clone,origin} independently.
2792 */
34dc7c2f 2793
b128c09f
BB		 2794 delta = pa->cloneusedsnap -
2795 dd->dd_phys->dd_used_breakdown[DD_USED_SNAP];
2796 ASSERT3S(delta, >=, 0);
2797 ASSERT3U(pa->used, >=, delta);
2798 dsl_dir_diduse_space(dd, DD_USED_SNAP, delta, 0, 0, tx);
2799 dsl_dir_diduse_space(dd, DD_USED_HEAD,
2800 pa->used - delta, pa->comp, pa->uncomp, tx);
2801
2802 delta = pa->originusedsnap -
2803 odd->dd_phys->dd_used_breakdown[DD_USED_SNAP];
2804 ASSERT3S(delta, <=, 0);
2805 ASSERT3U(pa->used, >=, -delta);
2806 dsl_dir_diduse_space(odd, DD_USED_SNAP, delta, 0, 0, tx);
2807 dsl_dir_diduse_space(odd, DD_USED_HEAD,
2808 -pa->used - delta, -pa->comp, -pa->uncomp, tx);
34dc7c2f 2809
34dc7c2f
BB		 2810 origin_ds->ds_phys->ds_unique_bytes = pa->unique;
2811
2812 /* log history record */
428870ff
BB		 2813 spa_history_log_internal(LOG_DS_PROMOTE, dd->dd_pool->dp_spa, tx,
2814 "dataset = %llu", hds->ds_object);
34dc7c2f
BB		 2815
2816 dsl_dir_close(odd, FTAG);
34dc7c2f
BB		 2817}
2818
b128c09f
BB		 2819static char *snaplist_tag = "snaplist";
2820/*
2821 * Make a list of dsl_dataset_t's for the snapshots between first_obj
2822 * (exclusive) and last_obj (inclusive). The list will be in reverse
2823 * order (last_obj will be the list_head()). If first_obj == 0, do all
2824 * snapshots back to this dataset's origin.
2825 */
2826static int
2827snaplist_make(dsl_pool_t *dp, boolean_t own,
2828 uint64_t first_obj, uint64_t last_obj, list_t *l)
2829{
2830 uint64_t obj = last_obj;
2831
2832 ASSERT(RW_LOCK_HELD(&dp->dp_config_rwlock));
2833
2834 list_create(l, sizeof (struct promotenode),
2835 offsetof(struct promotenode, link));
2836
2837 while (obj != first_obj) {
2838 dsl_dataset_t *ds;
2839 struct promotenode *snap;
2840 int err;
2841
2842 if (own) {
2843 err = dsl_dataset_own_obj(dp, obj,
2844 0, snaplist_tag, &ds);
2845 if (err == 0)
2846 dsl_dataset_make_exclusive(ds, snaplist_tag);
2847 } else {
2848 err = dsl_dataset_hold_obj(dp, obj, snaplist_tag, &ds);
2849 }
2850 if (err == ENOENT) {
2851 /* lost race with snapshot destroy */
2852 struct promotenode *last = list_tail(l);
2853 ASSERT(obj != last->ds->ds_phys->ds_prev_snap_obj);
2854 obj = last->ds->ds_phys->ds_prev_snap_obj;
2855 continue;
2856 } else if (err) {
2857 return (err);
2858 }
2859
2860 if (first_obj == 0)
2861 first_obj = ds->ds_dir->dd_phys->dd_origin_obj;
2862
2863 snap = kmem_alloc(sizeof (struct promotenode), KM_SLEEP);
2864 snap->ds = ds;
2865 list_insert_tail(l, snap);
2866 obj = ds->ds_phys->ds_prev_snap_obj;
2867 }
2868
2869 return (0);
2870}
2871
2872static int
2873snaplist_space(list_t *l, uint64_t mintxg, uint64_t *spacep)
2874{
2875 struct promotenode *snap;
2876
2877 *spacep = 0;
2878 for (snap = list_head(l); snap; snap = list_next(l, snap)) {
428870ff
BB		 2879 uint64_t used, comp, uncomp;
2880 dsl_deadlist_space_range(&snap->ds->ds_deadlist,
2881 mintxg, UINT64_MAX, &used, &comp, &uncomp);
b128c09f
BB		 2882 *spacep += used;
2883 }
2884 return (0);
2885}
2886
2887static void
2888snaplist_destroy(list_t *l, boolean_t own)
2889{
2890 struct promotenode *snap;
2891
9babb374 2892 if (!l || !list_link_active(&l->list_head))
b128c09f
BB		 2893 return;
2894
2895 while ((snap = list_tail(l)) != NULL) {
2896 list_remove(l, snap);
2897 if (own)
2898 dsl_dataset_disown(snap->ds, snaplist_tag);
2899 else
2900 dsl_dataset_rele(snap->ds, snaplist_tag);
2901 kmem_free(snap, sizeof (struct promotenode));
2902 }
2903 list_destroy(l);
2904}
2905
2906/*
2907 * Promote a clone. Nomenclature note:
2908 * "clone" or "cds": the original clone which is being promoted
2909 * "origin" or "ods": the snapshot which is originally clone's origin
2910 * "origin head" or "ohds": the dataset which is the head
2911 * (filesystem/volume) for the origin
2912 * "origin origin": the origin of the origin's filesystem (typically
2913 * NULL, indicating that the clone is not a clone of a clone).
2914 */
34dc7c2f 2915int
428870ff 2916dsl_dataset_promote(const char *name, char *conflsnap)
34dc7c2f
BB		 2917{
2918 dsl_dataset_t *ds;
b128c09f
BB		 2919 dsl_dir_t *dd;
2920 dsl_pool_t *dp;
34dc7c2f 2921 dmu_object_info_t doi;
b128c09f
BB		 2922 struct promotearg pa = { 0 };
2923 struct promotenode *snap;
2924 int err;
34dc7c2f 2925
b128c09f 2926 err = dsl_dataset_hold(name, FTAG, &ds);
34dc7c2f
BB		 2927 if (err)
2928 return (err);
b128c09f
BB		 2929 dd = ds->ds_dir;
2930 dp = dd->dd_pool;
34dc7c2f 2931
b128c09f 2932 err = dmu_object_info(dp->dp_meta_objset,
34dc7c2f
BB		 2933 ds->ds_phys->ds_snapnames_zapobj, &doi);
2934 if (err) {
b128c09f 2935 dsl_dataset_rele(ds, FTAG);
34dc7c2f
BB		 2936 return (err);
2937 }
2938
b128c09f
BB		 2939 if (dsl_dataset_is_snapshot(ds) || dd->dd_phys->dd_origin_obj == 0) {
2940 dsl_dataset_rele(ds, FTAG);
2941 return (EINVAL);
2942 }
2943
2944 /*
2945 * We are going to inherit all the snapshots taken before our
2946 * origin (i.e., our new origin will be our parent's origin).
2947 * Take ownership of them so that we can rename them into our
2948 * namespace.
2949 */
2950 rw_enter(&dp->dp_config_rwlock, RW_READER);
2951
2952 err = snaplist_make(dp, B_TRUE, 0, dd->dd_phys->dd_origin_obj,
2953 &pa.shared_snaps);
2954 if (err != 0)
2955 goto out;
2956
2957 err = snaplist_make(dp, B_FALSE, 0, ds->ds_object, &pa.clone_snaps);
2958 if (err != 0)
2959 goto out;
2960
2961 snap = list_head(&pa.shared_snaps);
2962 ASSERT3U(snap->ds->ds_object, ==, dd->dd_phys->dd_origin_obj);
2963 err = snaplist_make(dp, B_FALSE, dd->dd_phys->dd_origin_obj,
2964 snap->ds->ds_dir->dd_phys->dd_head_dataset_obj, &pa.origin_snaps);
2965 if (err != 0)
2966 goto out;
2967
428870ff
BB		 2968 if (snap->ds->ds_dir->dd_phys->dd_origin_obj != 0) {
2969 err = dsl_dataset_hold_obj(dp,
b128c09f 2970 snap->ds->ds_dir->dd_phys->dd_origin_obj,
428870ff 2971 FTAG, &pa.origin_origin);
b128c09f
BB		 2972 if (err != 0)
2973 goto out;
2974 }
2975
2976out:
2977 rw_exit(&dp->dp_config_rwlock);
2978
34dc7c2f
BB		 2979 /*
2980 * Add in 128x the snapnames zapobj size, since we will be moving
2981 * a bunch of snapnames to the promoted ds, and dirtying their
2982 * bonus buffers.
2983 */
b128c09f
BB		 2984 if (err == 0) {
2985 err = dsl_sync_task_do(dp, dsl_dataset_promote_check,
2986 dsl_dataset_promote_sync, ds, &pa,
428870ff
BB		 2987 2 + 2 * doi.doi_physical_blocks_512);
2988 if (err && pa.err_ds && conflsnap)
2989 (void) strncpy(conflsnap, pa.err_ds, MAXNAMELEN);
b128c09f
BB		 2990 }
2991
2992 snaplist_destroy(&pa.shared_snaps, B_TRUE);
2993 snaplist_destroy(&pa.clone_snaps, B_FALSE);
2994 snaplist_destroy(&pa.origin_snaps, B_FALSE);
2995 if (pa.origin_origin)
428870ff 2996 dsl_dataset_rele(pa.origin_origin, FTAG);
b128c09f 2997 dsl_dataset_rele(ds, FTAG);
34dc7c2f
BB		 2998 return (err);
2999}
3000
3001struct cloneswaparg {
3002 dsl_dataset_t *cds; /* clone dataset */
3003 dsl_dataset_t *ohds; /* origin's head dataset */
3004 boolean_t force;
3005 int64_t unused_refres_delta; /* change in unconsumed refreservation */
3006};
3007
3008/* ARGSUSED */
3009static int
3010dsl_dataset_clone_swap_check(void *arg1, void *arg2, dmu_tx_t *tx)
3011{
3012 struct cloneswaparg *csa = arg1;
3013
3014 /* they should both be heads */
3015 if (dsl_dataset_is_snapshot(csa->cds) ||
3016 dsl_dataset_is_snapshot(csa->ohds))
3017 return (EINVAL);
3018
3019 /* the branch point should be just before them */
3020 if (csa->cds->ds_prev != csa->ohds->ds_prev)
3021 return (EINVAL);
3022
428870ff
BB		 3023 /* cds should be the clone (unless they are unrelated) */
3024 if (csa->cds->ds_prev != NULL &&
3025 csa->cds->ds_prev != csa->cds->ds_dir->dd_pool->dp_origin_snap &&
3026 csa->ohds->ds_object !=
3027 csa->cds->ds_prev->ds_phys->ds_next_snap_obj)
34dc7c2f
BB		 3028 return (EINVAL);
3029
3030 /* the clone should be a child of the origin */
3031 if (csa->cds->ds_dir->dd_parent != csa->ohds->ds_dir)
3032 return (EINVAL);
3033
3034 /* ohds shouldn't be modified unless 'force' */
3035 if (!csa->force && dsl_dataset_modified_since_lastsnap(csa->ohds))
3036 return (ETXTBSY);
3037
3038 /* adjust amount of any unconsumed refreservation */
3039 csa->unused_refres_delta =
3040 (int64_t)MIN(csa->ohds->ds_reserved,
3041 csa->ohds->ds_phys->ds_unique_bytes) -
3042 (int64_t)MIN(csa->ohds->ds_reserved,
3043 csa->cds->ds_phys->ds_unique_bytes);
3044
3045 if (csa->unused_refres_delta > 0 &&
3046 csa->unused_refres_delta >
3047 dsl_dir_space_available(csa->ohds->ds_dir, NULL, 0, TRUE))
3048 return (ENOSPC);
3049
428870ff
BB		 3050 if (csa->ohds->ds_quota != 0 &&
3051 csa->cds->ds_phys->ds_unique_bytes > csa->ohds->ds_quota)
3052 return (EDQUOT);
3053
34dc7c2f
BB		 3054 return (0);
3055}
3056
3057/* ARGSUSED */
3058static void
428870ff 3059dsl_dataset_clone_swap_sync(void *arg1, void *arg2, dmu_tx_t *tx)
34dc7c2f
BB		 3060{
3061 struct cloneswaparg *csa = arg1;
3062 dsl_pool_t *dp = csa->cds->ds_dir->dd_pool;
34dc7c2f
BB		 3063
3064 ASSERT(csa->cds->ds_reserved == 0);
428870ff
BB		 3065 ASSERT(csa->ohds->ds_quota == 0 ||
3066 csa->cds->ds_phys->ds_unique_bytes <= csa->ohds->ds_quota);
34dc7c2f
BB		 3067
3068 dmu_buf_will_dirty(csa->cds->ds_dbuf, tx);
3069 dmu_buf_will_dirty(csa->ohds->ds_dbuf, tx);
34dc7c2f 3070
428870ff
BB		 3071 if (csa->cds->ds_objset != NULL) {
3072 dmu_objset_evict(csa->cds->ds_objset);
3073 csa->cds->ds_objset = NULL;
34dc7c2f
BB		 3074 }
3075
428870ff
BB		 3076 if (csa->ohds->ds_objset != NULL) {
3077 dmu_objset_evict(csa->ohds->ds_objset);
3078 csa->ohds->ds_objset = NULL;
34dc7c2f
BB		 3079 }
3080
428870ff
BB		 3081 /*
3082 * Reset origin's unique bytes, if it exists.
3083 */
3084 if (csa->cds->ds_prev) {
3085 dsl_dataset_t *origin = csa->cds->ds_prev;
3086 uint64_t comp, uncomp;
3087
3088 dmu_buf_will_dirty(origin->ds_dbuf, tx);
3089 dsl_deadlist_space_range(&csa->cds->ds_deadlist,
3090 origin->ds_phys->ds_prev_snap_txg, UINT64_MAX,
3091 &origin->ds_phys->ds_unique_bytes, &comp, &uncomp);
3092 }
34dc7c2f
BB		 3093
3094 /* swap blkptrs */
3095 {
3096 blkptr_t tmp;
3097 tmp = csa->ohds->ds_phys->ds_bp;
3098 csa->ohds->ds_phys->ds_bp = csa->cds->ds_phys->ds_bp;
3099 csa->cds->ds_phys->ds_bp = tmp;
3100 }
3101
3102 /* set dd_*_bytes */
3103 {
3104 int64_t dused, dcomp, duncomp;
3105 uint64_t cdl_used, cdl_comp, cdl_uncomp;
3106 uint64_t odl_used, odl_comp, odl_uncomp;
3107
b128c09f
BB		 3108 ASSERT3U(csa->cds->ds_dir->dd_phys->
3109 dd_used_breakdown[DD_USED_SNAP], ==, 0);
3110
428870ff
BB		 3111 dsl_deadlist_space(&csa->cds->ds_deadlist,
3112 &cdl_used, &cdl_comp, &cdl_uncomp);
3113 dsl_deadlist_space(&csa->ohds->ds_deadlist,
3114 &odl_used, &odl_comp, &odl_uncomp);
b128c09f 3115
34dc7c2f
BB		 3116 dused = csa->cds->ds_phys->ds_used_bytes + cdl_used -
3117 (csa->ohds->ds_phys->ds_used_bytes + odl_used);
3118 dcomp = csa->cds->ds_phys->ds_compressed_bytes + cdl_comp -
3119 (csa->ohds->ds_phys->ds_compressed_bytes + odl_comp);
3120 duncomp = csa->cds->ds_phys->ds_uncompressed_bytes +
3121 cdl_uncomp -
3122 (csa->ohds->ds_phys->ds_uncompressed_bytes + odl_uncomp);
3123
b128c09f 3124 dsl_dir_diduse_space(csa->ohds->ds_dir, DD_USED_HEAD,
34dc7c2f 3125 dused, dcomp, duncomp, tx);
b128c09f 3126 dsl_dir_diduse_space(csa->cds->ds_dir, DD_USED_HEAD,
34dc7c2f 3127 -dused, -dcomp, -duncomp, tx);
b128c09f
BB		 3128
3129 /*
3130 * The difference in the space used by snapshots is the
3131 * difference in snapshot space due to the head's
3132 * deadlist (since that's the only thing that's
3133 * changing that affects the snapused).
3134 */
428870ff
BB		 3135 dsl_deadlist_space_range(&csa->cds->ds_deadlist,
3136 csa->ohds->ds_dir->dd_origin_txg, UINT64_MAX,
3137 &cdl_used, &cdl_comp, &cdl_uncomp);
3138 dsl_deadlist_space_range(&csa->ohds->ds_deadlist,
3139 csa->ohds->ds_dir->dd_origin_txg, UINT64_MAX,
3140 &odl_used, &odl_comp, &odl_uncomp);
b128c09f
BB		 3141 dsl_dir_transfer_space(csa->ohds->ds_dir, cdl_used - odl_used,
3142 DD_USED_HEAD, DD_USED_SNAP, tx);
34dc7c2f
BB		 3143 }
3144
34dc7c2f
BB		 3145 /* swap ds_*_bytes */
3146 SWITCH64(csa->ohds->ds_phys->ds_used_bytes,
3147 csa->cds->ds_phys->ds_used_bytes);
3148 SWITCH64(csa->ohds->ds_phys->ds_compressed_bytes,
3149 csa->cds->ds_phys->ds_compressed_bytes);
3150 SWITCH64(csa->ohds->ds_phys->ds_uncompressed_bytes,
3151 csa->cds->ds_phys->ds_uncompressed_bytes);
3152 SWITCH64(csa->ohds->ds_phys->ds_unique_bytes,
3153 csa->cds->ds_phys->ds_unique_bytes);
3154
3155 /* apply any parent delta for change in unconsumed refreservation */
b128c09f
BB		 3156 dsl_dir_diduse_space(csa->ohds->ds_dir, DD_USED_REFRSRV,
3157 csa->unused_refres_delta, 0, 0, tx);
34dc7c2f 3158
428870ff
BB		 3159 /*
3160 * Swap deadlists.
3161 */
3162 dsl_deadlist_close(&csa->cds->ds_deadlist);
3163 dsl_deadlist_close(&csa->ohds->ds_deadlist);
34dc7c2f
BB		 3164 SWITCH64(csa->ohds->ds_phys->ds_deadlist_obj,
3165 csa->cds->ds_phys->ds_deadlist_obj);
428870ff
BB		 3166 dsl_deadlist_open(&csa->cds->ds_deadlist, dp->dp_meta_objset,
3167 csa->cds->ds_phys->ds_deadlist_obj);
3168 dsl_deadlist_open(&csa->ohds->ds_deadlist, dp->dp_meta_objset,
3169 csa->ohds->ds_phys->ds_deadlist_obj);
b128c09f 3170
428870ff 3171 dsl_scan_ds_clone_swapped(csa->ohds, csa->cds, tx);
34dc7c2f
BB		 3172}
3173
3174/*
428870ff
BB		 3175 * Swap 'clone' with its origin head datasets. Used at the end of "zfs
3176 * recv" into an existing fs to swizzle the file system to the new
3177 * version, and by "zfs rollback". Can also be used to swap two
3178 * independent head datasets if neither has any snapshots.
34dc7c2f
BB		 3179 */
3180int
3181dsl_dataset_clone_swap(dsl_dataset_t *clone, dsl_dataset_t *origin_head,
3182 boolean_t force)
3183{
3184 struct cloneswaparg csa;
b128c09f 3185 int error;
34dc7c2f 3186
b128c09f
BB		 3187 ASSERT(clone->ds_owner);
3188 ASSERT(origin_head->ds_owner);
3189retry:
572e2857
BB		 3190 /*
3191 * Need exclusive access for the swap. If we're swapping these
3192 * datasets back after an error, we already hold the locks.
3193 */
3194 if (!RW_WRITE_HELD(&clone->ds_rwlock))
3195 rw_enter(&clone->ds_rwlock, RW_WRITER);
3196 if (!RW_WRITE_HELD(&origin_head->ds_rwlock) &&
3197 !rw_tryenter(&origin_head->ds_rwlock, RW_WRITER)) {
b128c09f
BB		 3198 rw_exit(&clone->ds_rwlock);
3199 rw_enter(&origin_head->ds_rwlock, RW_WRITER);
3200 if (!rw_tryenter(&clone->ds_rwlock, RW_WRITER)) {
3201 rw_exit(&origin_head->ds_rwlock);
3202 goto retry;
3203 }
3204 }
34dc7c2f
BB		 3205 csa.cds = clone;
3206 csa.ohds = origin_head;
3207 csa.force = force;
b128c09f 3208 error = dsl_sync_task_do(clone->ds_dir->dd_pool,
34dc7c2f 3209 dsl_dataset_clone_swap_check,
b128c09f
BB		 3210 dsl_dataset_clone_swap_sync, &csa, NULL, 9);
3211 return (error);
34dc7c2f
BB		 3212}
3213
3214/*
3215 * Given a pool name and a dataset object number in that pool,
3216 * return the name of that dataset.
3217 */
3218int
3219dsl_dsobj_to_dsname(char *pname, uint64_t obj, char *buf)
3220{
3221 spa_t *spa;
3222 dsl_pool_t *dp;
b128c09f 3223 dsl_dataset_t *ds;
34dc7c2f
BB		 3224 int error;
3225
3226 if ((error = spa_open(pname, &spa, FTAG)) != 0)
3227 return (error);
3228 dp = spa_get_dsl(spa);
3229 rw_enter(&dp->dp_config_rwlock, RW_READER);
b128c09f
BB		 3230 if ((error = dsl_dataset_hold_obj(dp, obj, FTAG, &ds)) == 0) {
3231 dsl_dataset_name(ds, buf);
3232 dsl_dataset_rele(ds, FTAG);
34dc7c2f 3233 }
34dc7c2f
BB		 3234 rw_exit(&dp->dp_config_rwlock);
3235 spa_close(spa, FTAG);
3236
b128c09f 3237 return (error);
34dc7c2f
BB		 3238}
3239
3240int
3241dsl_dataset_check_quota(dsl_dataset_t *ds, boolean_t check_quota,
b128c09f 3242 uint64_t asize, uint64_t inflight, uint64_t *used, uint64_t *ref_rsrv)
34dc7c2f
BB		 3243{
3244 int error = 0;
3245
3246 ASSERT3S(asize, >, 0);
3247
3248 /*
3249 * *ref_rsrv is the portion of asize that will come from any
3250 * unconsumed refreservation space.
3251 */
3252 *ref_rsrv = 0;
3253
3254 mutex_enter(&ds->ds_lock);
3255 /*
3256 * Make a space adjustment for reserved bytes.
3257 */
3258 if (ds->ds_reserved > ds->ds_phys->ds_unique_bytes) {
3259 ASSERT3U(*used, >=,
3260 ds->ds_reserved - ds->ds_phys->ds_unique_bytes);
3261 *used -= (ds->ds_reserved - ds->ds_phys->ds_unique_bytes);
3262 *ref_rsrv =
3263 asize - MIN(asize, parent_delta(ds, asize + inflight));
3264 }
3265
3266 if (!check_quota || ds->ds_quota == 0) {
3267 mutex_exit(&ds->ds_lock);
3268 return (0);
3269 }
3270 /*
3271 * If they are requesting more space, and our current estimate
3272 * is over quota, they get to try again unless the actual
3273 * on-disk is over quota and there are no pending changes (which
3274 * may free up space for us).
3275 */
3276 if (ds->ds_phys->ds_used_bytes + inflight >= ds->ds_quota) {
3277 if (inflight > 0 || ds->ds_phys->ds_used_bytes < ds->ds_quota)
3278 error = ERESTART;
3279 else
3280 error = EDQUOT;
3281 }
3282 mutex_exit(&ds->ds_lock);
3283
3284 return (error);
3285}
3286
3287/* ARGSUSED */
3288static int
3289dsl_dataset_set_quota_check(void *arg1, void *arg2, dmu_tx_t *tx)
3290{
3291 dsl_dataset_t *ds = arg1;
428870ff
BB		 3292 dsl_prop_setarg_t *psa = arg2;
3293 int err;
34dc7c2f
BB		 3294
3295 if (spa_version(ds->ds_dir->dd_pool->dp_spa) < SPA_VERSION_REFQUOTA)
3296 return (ENOTSUP);
3297
428870ff
BB		 3298 if ((err = dsl_prop_predict_sync(ds->ds_dir, psa)) != 0)
3299 return (err);
3300
3301 if (psa->psa_effective_value == 0)
34dc7c2f
BB		 3302 return (0);
3303
428870ff
BB		 3304 if (psa->psa_effective_value < ds->ds_phys->ds_used_bytes ||
3305 psa->psa_effective_value < ds->ds_reserved)
34dc7c2f
BB		 3306 return (ENOSPC);
3307
3308 return (0);
3309}
3310
428870ff
BB		 3311extern void dsl_prop_set_sync(void *, void *, dmu_tx_t *);
3312
34dc7c2f 3313void
428870ff 3314dsl_dataset_set_quota_sync(void *arg1, void *arg2, dmu_tx_t *tx)
34dc7c2f
BB		 3315{
3316 dsl_dataset_t *ds = arg1;
428870ff
BB		 3317 dsl_prop_setarg_t *psa = arg2;
3318 uint64_t effective_value = psa->psa_effective_value;
34dc7c2f 3319
428870ff
BB		 3320 dsl_prop_set_sync(ds, psa, tx);
3321 DSL_PROP_CHECK_PREDICTION(ds->ds_dir, psa);
34dc7c2f 3322
428870ff
BB		 3323 if (ds->ds_quota != effective_value) {
3324 dmu_buf_will_dirty(ds->ds_dbuf, tx);
3325 ds->ds_quota = effective_value;
34dc7c2f 3326
428870ff
BB		 3327 spa_history_log_internal(LOG_DS_REFQUOTA,
3328 ds->ds_dir->dd_pool->dp_spa, tx, "%lld dataset = %llu ",
3329 (longlong_t)ds->ds_quota, ds->ds_object);
3330 }
34dc7c2f
BB		 3331}
3332
3333int
428870ff 3334dsl_dataset_set_quota(const char *dsname, zprop_source_t source, uint64_t quota)
34dc7c2f
BB		 3335{
3336 dsl_dataset_t *ds;
428870ff 3337 dsl_prop_setarg_t psa;
34dc7c2f
BB		 3338 int err;
3339
428870ff
BB		 3340 dsl_prop_setarg_init_uint64(&psa, "refquota", source, &quota);
3341
b128c09f 3342 err = dsl_dataset_hold(dsname, FTAG, &ds);
34dc7c2f
BB		 3343 if (err)
3344 return (err);
3345
428870ff
BB		 3346 /*
3347 * If someone removes a file, then tries to set the quota, we
3348 * want to make sure the file freeing takes effect.
3349 */
3350 txg_wait_open(ds->ds_dir->dd_pool, 0);
3351
3352 err = dsl_sync_task_do(ds->ds_dir->dd_pool,
3353 dsl_dataset_set_quota_check, dsl_dataset_set_quota_sync,
3354 ds, &psa, 0);
34dc7c2f 3355
b128c09f 3356 dsl_dataset_rele(ds, FTAG);
34dc7c2f
BB		 3357 return (err);
3358}
3359
3360static int
3361dsl_dataset_set_reservation_check(void *arg1, void *arg2, dmu_tx_t *tx)
3362{
3363 dsl_dataset_t *ds = arg1;
428870ff
BB		 3364 dsl_prop_setarg_t *psa = arg2;
3365 uint64_t effective_value;
34dc7c2f 3366 uint64_t unique;
428870ff 3367 int err;
34dc7c2f 3368
34dc7c2f
BB		 3369 if (spa_version(ds->ds_dir->dd_pool->dp_spa) <
3370 SPA_VERSION_REFRESERVATION)
3371 return (ENOTSUP);
3372
3373 if (dsl_dataset_is_snapshot(ds))
3374 return (EINVAL);
3375
428870ff
BB		 3376 if ((err = dsl_prop_predict_sync(ds->ds_dir, psa)) != 0)
3377 return (err);
3378
3379 effective_value = psa->psa_effective_value;
3380
34dc7c2f
BB		 3381 /*
3382 * If we are doing the preliminary check in open context, the
3383 * space estimates may be inaccurate.
3384 */
3385 if (!dmu_tx_is_syncing(tx))
3386 return (0);
3387
3388 mutex_enter(&ds->ds_lock);
428870ff
BB		 3389 if (!DS_UNIQUE_IS_ACCURATE(ds))
3390 dsl_dataset_recalc_head_uniq(ds);
3391 unique = ds->ds_phys->ds_unique_bytes;
34dc7c2f
BB		 3392 mutex_exit(&ds->ds_lock);
3393
428870ff
BB		 3394 if (MAX(unique, effective_value) > MAX(unique, ds->ds_reserved)) {
3395 uint64_t delta = MAX(unique, effective_value) -
d164b209
BB		 3396 MAX(unique, ds->ds_reserved);
3397
3398 if (delta > dsl_dir_space_available(ds->ds_dir, NULL, 0, TRUE))
3399 return (ENOSPC);
3400 if (ds->ds_quota > 0 &&
428870ff 3401 effective_value > ds->ds_quota)
d164b209
BB		 3402 return (ENOSPC);
3403 }
34dc7c2f
BB		 3404
3405 return (0);
3406}
3407
34dc7c2f 3408static void
428870ff 3409dsl_dataset_set_reservation_sync(void *arg1, void *arg2, dmu_tx_t *tx)
34dc7c2f
BB		 3410{
3411 dsl_dataset_t *ds = arg1;
428870ff
BB		 3412 dsl_prop_setarg_t *psa = arg2;
3413 uint64_t effective_value = psa->psa_effective_value;
34dc7c2f
BB		 3414 uint64_t unique;
3415 int64_t delta;
3416
428870ff
BB		 3417 dsl_prop_set_sync(ds, psa, tx);
3418 DSL_PROP_CHECK_PREDICTION(ds->ds_dir, psa);
3419
34dc7c2f
BB		 3420 dmu_buf_will_dirty(ds->ds_dbuf, tx);
3421
b128c09f 3422 mutex_enter(&ds->ds_dir->dd_lock);
34dc7c2f 3423 mutex_enter(&ds->ds_lock);
428870ff
BB		 3424 ASSERT(DS_UNIQUE_IS_ACCURATE(ds));
3425 unique = ds->ds_phys->ds_unique_bytes;
3426 delta = MAX(0, (int64_t)(effective_value - unique)) -
34dc7c2f 3427 MAX(0, (int64_t)(ds->ds_reserved - unique));
428870ff 3428 ds->ds_reserved = effective_value;
34dc7c2f
BB		 3429 mutex_exit(&ds->ds_lock);
3430
b128c09f
BB		 3431 dsl_dir_diduse_space(ds->ds_dir, DD_USED_REFRSRV, delta, 0, 0, tx);
3432 mutex_exit(&ds->ds_dir->dd_lock);
34dc7c2f 3433
428870ff
BB		 3434 spa_history_log_internal(LOG_DS_REFRESERV,
3435 ds->ds_dir->dd_pool->dp_spa, tx, "%lld dataset = %llu",
3436 (longlong_t)effective_value, ds->ds_object);
34dc7c2f
BB		 3437}
3438
3439int
428870ff
BB		 3440dsl_dataset_set_reservation(const char *dsname, zprop_source_t source,
3441 uint64_t reservation)
34dc7c2f
BB		 3442{
3443 dsl_dataset_t *ds;
428870ff 3444 dsl_prop_setarg_t psa;
34dc7c2f
BB		 3445 int err;
3446
428870ff
BB		 3447 dsl_prop_setarg_init_uint64(&psa, "refreservation", source,
3448 &reservation);
3449
b128c09f 3450 err = dsl_dataset_hold(dsname, FTAG, &ds);
34dc7c2f
BB		 3451 if (err)
3452 return (err);
3453
3454 err = dsl_sync_task_do(ds->ds_dir->dd_pool,
3455 dsl_dataset_set_reservation_check,
428870ff
BB		 3456 dsl_dataset_set_reservation_sync, ds, &psa, 0);
3457
b128c09f 3458 dsl_dataset_rele(ds, FTAG);
34dc7c2f
BB		 3459 return (err);
3460}
45d1cae3 3461
572e2857
BB		 3462typedef struct zfs_hold_cleanup_arg {
3463 dsl_pool_t *dp;
3464 uint64_t dsobj;
3465 char htag[MAXNAMELEN];
3466} zfs_hold_cleanup_arg_t;
3467
3468static void
3469dsl_dataset_user_release_onexit(void *arg)
3470{
3471 zfs_hold_cleanup_arg_t *ca = arg;
3472
3473 (void) dsl_dataset_user_release_tmp(ca->dp, ca->dsobj, ca->htag,
3474 B_TRUE);
3475 kmem_free(ca, sizeof (zfs_hold_cleanup_arg_t));
3476}
3477
3478void
3479dsl_register_onexit_hold_cleanup(dsl_dataset_t *ds, const char *htag,
3480 minor_t minor)
3481{
3482 zfs_hold_cleanup_arg_t *ca;
3483
3484 ca = kmem_alloc(sizeof (zfs_hold_cleanup_arg_t), KM_SLEEP);
3485 ca->dp = ds->ds_dir->dd_pool;
3486 ca->dsobj = ds->ds_object;
3487 (void) strlcpy(ca->htag, htag, sizeof (ca->htag));
3488 VERIFY3U(0, ==, zfs_onexit_add_cb(minor,
3489 dsl_dataset_user_release_onexit, ca, NULL));
3490}
428870ff
BB		 3491
3492/*
572e2857
BB		 3493 * If you add new checks here, you may need to add
3494 * additional checks to the "temporary" case in
3495 * snapshot_check() in dmu_objset.c.
428870ff 3496 */
45d1cae3
BB		 3497static int
3498dsl_dataset_user_hold_check(void *arg1, void *arg2, dmu_tx_t *tx)
3499{
3500 dsl_dataset_t *ds = arg1;
428870ff
BB		 3501 struct dsl_ds_holdarg *ha = arg2;
3502 char *htag = ha->htag;
45d1cae3
BB		 3503 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
3504 int error = 0;
3505
3506 if (spa_version(ds->ds_dir->dd_pool->dp_spa) < SPA_VERSION_USERREFS)
3507 return (ENOTSUP);
3508
3509 if (!dsl_dataset_is_snapshot(ds))
3510 return (EINVAL);
3511
45d1cae3
BB		 3512 /* tags must be unique */
3513 mutex_enter(&ds->ds_lock);
3514 if (ds->ds_phys->ds_userrefs_obj) {
3515 error = zap_lookup(mos, ds->ds_phys->ds_userrefs_obj, htag,
3516 8, 1, tx);
3517 if (error == 0)
3518 error = EEXIST;
3519 else if (error == ENOENT)
3520 error = 0;
3521 }
3522 mutex_exit(&ds->ds_lock);
3523
428870ff
BB		 3524 if (error == 0 && ha->temphold &&
3525 strlen(htag) + MAX_TAG_PREFIX_LEN >= MAXNAMELEN)
3526 error = E2BIG;
3527
45d1cae3
BB		 3528 return (error);
3529}
3530
572e2857 3531void
428870ff 3532dsl_dataset_user_hold_sync(void *arg1, void *arg2, dmu_tx_t *tx)
45d1cae3
BB		 3533{
3534 dsl_dataset_t *ds = arg1;
428870ff
BB		 3535 struct dsl_ds_holdarg *ha = arg2;
3536 char *htag = ha->htag;
3537 dsl_pool_t *dp = ds->ds_dir->dd_pool;
3538 objset_t *mos = dp->dp_meta_objset;
3539 uint64_t now = gethrestime_sec();
45d1cae3
BB		 3540 uint64_t zapobj;
3541
3542 mutex_enter(&ds->ds_lock);
3543 if (ds->ds_phys->ds_userrefs_obj == 0) {
3544 /*
3545 * This is the first user hold for this dataset. Create
3546 * the userrefs zap object.
3547 */
3548 dmu_buf_will_dirty(ds->ds_dbuf, tx);
3549 zapobj = ds->ds_phys->ds_userrefs_obj =
3550 zap_create(mos, DMU_OT_USERREFS, DMU_OT_NONE, 0, tx);
3551 } else {
3552 zapobj = ds->ds_phys->ds_userrefs_obj;
3553 }
3554 ds->ds_userrefs++;
3555 mutex_exit(&ds->ds_lock);
3556
3557 VERIFY(0 == zap_add(mos, zapobj, htag, 8, 1, &now, tx));
3558
428870ff
BB		 3559 if (ha->temphold) {
3560 VERIFY(0 == dsl_pool_user_hold(dp, ds->ds_object,
3561 htag, &now, tx));
3562 }
45d1cae3 3563
428870ff
BB		 3564 spa_history_log_internal(LOG_DS_USER_HOLD,
3565 dp->dp_spa, tx, "<%s> temp = %d dataset = %llu", htag,
3566 (int)ha->temphold, ds->ds_object);
3567}
45d1cae3
BB		 3568
3569static int
428870ff 3570dsl_dataset_user_hold_one(const char *dsname, void *arg)
45d1cae3
BB		 3571{
3572 struct dsl_ds_holdarg *ha = arg;
3573 dsl_dataset_t *ds;
3574 int error;
3575 char *name;
45d1cae3
BB		 3576
3577 /* alloc a buffer to hold dsname@snapname plus terminating NULL */
428870ff 3578 name = kmem_asprintf("%s@%s", dsname, ha->snapname);
45d1cae3 3579 error = dsl_dataset_hold(name, ha->dstg, &ds);
428870ff 3580 strfree(name);
45d1cae3 3581 if (error == 0) {
428870ff 3582 ha->gotone = B_TRUE;
45d1cae3 3583 dsl_sync_task_create(ha->dstg, dsl_dataset_user_hold_check,
428870ff 3584 dsl_dataset_user_hold_sync, ds, ha, 0);
45d1cae3
BB		 3585 } else if (error == ENOENT && ha->recursive) {
3586 error = 0;
3587 } else {
428870ff 3588 (void) strlcpy(ha->failed, dsname, sizeof (ha->failed));
45d1cae3
BB		 3589 }
3590 return (error);
3591}
3592
572e2857
BB		 3593int
3594dsl_dataset_user_hold_for_send(dsl_dataset_t *ds, char *htag,
3595 boolean_t temphold)
3596{
3597 struct dsl_ds_holdarg *ha;
3598 int error;
3599
3600 ha = kmem_zalloc(sizeof (struct dsl_ds_holdarg), KM_SLEEP);
3601 ha->htag = htag;
3602 ha->temphold = temphold;
3603 error = dsl_sync_task_do(ds->ds_dir->dd_pool,
3604 dsl_dataset_user_hold_check, dsl_dataset_user_hold_sync,
3605 ds, ha, 0);
3606 kmem_free(ha, sizeof (struct dsl_ds_holdarg));
3607
3608 return (error);
3609}
3610
45d1cae3
BB		 3611int
3612dsl_dataset_user_hold(char *dsname, char *snapname, char *htag,
572e2857 3613 boolean_t recursive, boolean_t temphold, int cleanup_fd)
45d1cae3
BB		 3614{
3615 struct dsl_ds_holdarg *ha;
3616 dsl_sync_task_t *dst;
3617 spa_t *spa;
3618 int error;
572e2857
BB		 3619 minor_t minor = 0;
3620
3621 if (cleanup_fd != -1) {
3622 /* Currently we only support cleanup-on-exit of tempholds. */
3623 if (!temphold)
3624 return (EINVAL);
3625 error = zfs_onexit_fd_hold(cleanup_fd, &minor);
3626 if (error)
3627 return (error);
3628 }
45d1cae3
BB		 3629
3630 ha = kmem_zalloc(sizeof (struct dsl_ds_holdarg), KM_SLEEP);
3631
3632 (void) strlcpy(ha->failed, dsname, sizeof (ha->failed));
3633
3634 error = spa_open(dsname, &spa, FTAG);
3635 if (error) {
3636 kmem_free(ha, sizeof (struct dsl_ds_holdarg));
572e2857
BB		 3637 if (cleanup_fd != -1)
3638 zfs_onexit_fd_rele(cleanup_fd);
45d1cae3
BB		 3639 return (error);
3640 }
3641
3642 ha->dstg = dsl_sync_task_group_create(spa_get_dsl(spa));
3643 ha->htag = htag;
3644 ha->snapname = snapname;
3645 ha->recursive = recursive;
428870ff 3646 ha->temphold = temphold;
572e2857 3647
45d1cae3
BB		 3648 if (recursive) {
3649 error = dmu_objset_find(dsname, dsl_dataset_user_hold_one,
3650 ha, DS_FIND_CHILDREN);
3651 } else {
3652 error = dsl_dataset_user_hold_one(dsname, ha);
3653 }
3654 if (error == 0)
3655 error = dsl_sync_task_group_wait(ha->dstg);
3656
3657 for (dst = list_head(&ha->dstg->dstg_tasks); dst;
3658 dst = list_next(&ha->dstg->dstg_tasks, dst)) {
3659 dsl_dataset_t *ds = dst->dst_arg1;
3660
3661 if (dst->dst_err) {
3662 dsl_dataset_name(ds, ha->failed);
3663 *strchr(ha->failed, '@') = '\0';
572e2857
BB		 3664 } else if (error == 0 && minor != 0 && temphold) {
3665 /*
3666 * If this hold is to be released upon process exit,
3667 * register that action now.
3668 */
3669 dsl_register_onexit_hold_cleanup(ds, htag, minor);
45d1cae3
BB		 3670 }
3671 dsl_dataset_rele(ds, ha->dstg);
3672 }
3673
428870ff
BB		 3674 if (error == 0 && recursive && !ha->gotone)
3675 error = ENOENT;
3676
45d1cae3 3677 if (error)
428870ff 3678 (void) strlcpy(dsname, ha->failed, sizeof (ha->failed));
45d1cae3
BB		 3679
3680 dsl_sync_task_group_destroy(ha->dstg);
572e2857 3681
45d1cae3
BB		 3682 kmem_free(ha, sizeof (struct dsl_ds_holdarg));
3683 spa_close(spa, FTAG);
572e2857
BB		 3684 if (cleanup_fd != -1)
3685 zfs_onexit_fd_rele(cleanup_fd);
45d1cae3
BB		 3686 return (error);
3687}
3688
3689struct dsl_ds_releasearg {
3690 dsl_dataset_t *ds;
3691 const char *htag;
3692 boolean_t own; /* do we own or just hold ds? */
3693};
3694
3695static int
3696dsl_dataset_release_might_destroy(dsl_dataset_t *ds, const char *htag,
3697 boolean_t *might_destroy)
3698{
3699 objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
3700 uint64_t zapobj;
3701 uint64_t tmp;
3702 int error;
3703
3704 *might_destroy = B_FALSE;
3705
3706 mutex_enter(&ds->ds_lock);
3707 zapobj = ds->ds_phys->ds_userrefs_obj;
3708 if (zapobj == 0) {
3709 /* The tag can't possibly exist */
3710 mutex_exit(&ds->ds_lock);
3711 return (ESRCH);
3712 }
3713
3714 /* Make sure the tag exists */
3715 error = zap_lookup(mos, zapobj, htag, 8, 1, &tmp);
3716 if (error) {
3717 mutex_exit(&ds->ds_lock);
3718 if (error == ENOENT)
3719 error = ESRCH;
3720 return (error);
3721 }
3722
3723 if (ds->ds_userrefs == 1 && ds->ds_phys->ds_num_children == 1 &&
3724 DS_IS_DEFER_DESTROY(ds))
3725 *might_destroy = B_TRUE;
3726
3727 mutex_exit(&ds->ds_lock);
3728 return (0);
3729}
3730
3731static int
3732dsl_dataset_user_release_check(void *arg1, void *tag, dmu_tx_t *tx)
3733{
3734 struct dsl_ds_releasearg *ra = arg1;
3735 dsl_dataset_t *ds = ra->ds;
3736 boolean_t might_destroy;
3737 int error;
3738
3739 if (spa_version(ds->ds_dir->dd_pool->dp_spa) < SPA_VERSION_USERREFS)
3740 return (ENOTSUP);
3741
3742 error = dsl_dataset_release_might_destroy(ds, ra->htag, &might_destroy);
3743 if (error)
3744 return (error);
3745
3746 if (might_destroy) {
3747 struct dsl_ds_destroyarg dsda = {0};
3748
3749 if (dmu_tx_is_syncing(tx)) {
3750 /*
3751 * If we're not prepared to remove the snapshot,
3752 * we can't allow the release to happen right now.
3753 */
3754 if (!ra->own)
3755 return (EBUSY);
45d1cae3
BB		 3756 }
3757 dsda.ds = ds;
3758 dsda.releasing = B_TRUE;
3759 return (dsl_dataset_destroy_check(&dsda, tag, tx));
3760 }
3761
3762 return (0);
3763}
3764
3765static void
428870ff 3766dsl_dataset_user_release_sync(void *arg1, void *tag, dmu_tx_t *tx)
45d1cae3
BB		 3767{
3768 struct dsl_ds_releasearg *ra = arg1;
3769 dsl_dataset_t *ds = ra->ds;
428870ff
BB		 3770 dsl_pool_t *dp = ds->ds_dir->dd_pool;
3771 objset_t *mos = dp->dp_meta_objset;
45d1cae3
BB		 3772 uint64_t zapobj;
3773 uint64_t dsobj = ds->ds_object;
3774 uint64_t refs;
428870ff
BB		 3775 int error;
3776
45d1cae3
BB		 3777 mutex_enter(&ds->ds_lock);
3778 ds->ds_userrefs--;
3779 refs = ds->ds_userrefs;
3780 mutex_exit(&ds->ds_lock);
428870ff
BB		 3781 error = dsl_pool_user_release(dp, ds->ds_object, ra->htag, tx);
3782 VERIFY(error == 0 || error == ENOENT);
45d1cae3
BB		 3783 zapobj = ds->ds_phys->ds_userrefs_obj;
3784 VERIFY(0 == zap_remove(mos, zapobj, ra->htag, tx));
3785 if (ds->ds_userrefs == 0 && ds->ds_phys->ds_num_children == 1 &&
3786 DS_IS_DEFER_DESTROY(ds)) {
3787 struct dsl_ds_destroyarg dsda = {0};
3788
3789 ASSERT(ra->own);
3790 dsda.ds = ds;
3791 dsda.releasing = B_TRUE;
3792 /* We already did the destroy_check */
428870ff 3793 dsl_dataset_destroy_sync(&dsda, tag, tx);
45d1cae3
BB		 3794 }
3795
428870ff
BB		 3796 spa_history_log_internal(LOG_DS_USER_RELEASE,
3797 dp->dp_spa, tx, "<%s> %lld dataset = %llu",
45d1cae3
BB		 3798 ra->htag, (longlong_t)refs, dsobj);
3799}
3800
3801static int
428870ff 3802dsl_dataset_user_release_one(const char *dsname, void *arg)
45d1cae3
BB		 3803{
3804 struct dsl_ds_holdarg *ha = arg;
3805 struct dsl_ds_releasearg *ra;
3806 dsl_dataset_t *ds;
3807 int error;
3808 void *dtag = ha->dstg;
3809 char *name;
45d1cae3
BB		 3810 boolean_t own = B_FALSE;
3811 boolean_t might_destroy;
3812
45d1cae3 3813 /* alloc a buffer to hold dsname@snapname, plus the terminating NULL */
428870ff 3814 name = kmem_asprintf("%s@%s", dsname, ha->snapname);
45d1cae3 3815 error = dsl_dataset_hold(name, dtag, &ds);
428870ff 3816 strfree(name);
45d1cae3
BB		 3817 if (error == ENOENT && ha->recursive)
3818 return (0);
428870ff 3819 (void) strlcpy(ha->failed, dsname, sizeof (ha->failed));
45d1cae3
BB		 3820 if (error)
3821 return (error);
3822
428870ff
BB		 3823 ha->gotone = B_TRUE;
3824
45d1cae3
BB		 3825 ASSERT(dsl_dataset_is_snapshot(ds));
3826
3827 error = dsl_dataset_release_might_destroy(ds, ha->htag, &might_destroy);
3828 if (error) {
3829 dsl_dataset_rele(ds, dtag);
3830 return (error);
3831 }
3832
3833 if (might_destroy) {
3834#ifdef _KERNEL
428870ff 3835 name = kmem_asprintf("%s@%s", dsname, ha->snapname);
45d1cae3 3836 error = zfs_unmount_snap(name, NULL);
428870ff 3837 strfree(name);
45d1cae3
BB		 3838 if (error) {
3839 dsl_dataset_rele(ds, dtag);
3840 return (error);
3841 }
3842#endif
428870ff 3843 if (!dsl_dataset_tryown(ds, B_TRUE, dtag)) {
45d1cae3
BB		 3844 dsl_dataset_rele(ds, dtag);
3845 return (EBUSY);
3846 } else {
3847 own = B_TRUE;
3848 dsl_dataset_make_exclusive(ds, dtag);
3849 }
3850 }
3851
3852 ra = kmem_alloc(sizeof (struct dsl_ds_releasearg), KM_SLEEP);
3853 ra->ds = ds;
3854 ra->htag = ha->htag;
3855 ra->own = own;
3856 dsl_sync_task_create(ha->dstg, dsl_dataset_user_release_check,
3857 dsl_dataset_user_release_sync, ra, dtag, 0);
3858
3859 return (0);
3860}
3861
3862int
3863dsl_dataset_user_release(char *dsname, char *snapname, char *htag,
3864 boolean_t recursive)
3865{
3866 struct dsl_ds_holdarg *ha;
3867 dsl_sync_task_t *dst;
3868 spa_t *spa;
3869 int error;
3870
428870ff 3871top:
45d1cae3
BB		 3872 ha = kmem_zalloc(sizeof (struct dsl_ds_holdarg), KM_SLEEP);
3873
3874 (void) strlcpy(ha->failed, dsname, sizeof (ha->failed));
3875
3876 error = spa_open(dsname, &spa, FTAG);
3877 if (error) {
3878 kmem_free(ha, sizeof (struct dsl_ds_holdarg));
3879 return (error);
3880 }
3881
3882 ha->dstg = dsl_sync_task_group_create(spa_get_dsl(spa));
3883 ha->htag = htag;
3884 ha->snapname = snapname;
3885 ha->recursive = recursive;
3886 if (recursive) {
3887 error = dmu_objset_find(dsname, dsl_dataset_user_release_one,
3888 ha, DS_FIND_CHILDREN);
3889 } else {
3890 error = dsl_dataset_user_release_one(dsname, ha);
3891 }
3892 if (error == 0)
3893 error = dsl_sync_task_group_wait(ha->dstg);
3894
3895 for (dst = list_head(&ha->dstg->dstg_tasks); dst;
3896 dst = list_next(&ha->dstg->dstg_tasks, dst)) {
3897 struct dsl_ds_releasearg *ra = dst->dst_arg1;
3898 dsl_dataset_t *ds = ra->ds;
3899
3900 if (dst->dst_err)
3901 dsl_dataset_name(ds, ha->failed);
3902
3903 if (ra->own)
3904 dsl_dataset_disown(ds, ha->dstg);
3905 else
3906 dsl_dataset_rele(ds, ha->dstg);
3907
3908 kmem_free(ra, sizeof (struct dsl_ds_releasearg));
3909 }
3910
428870ff
BB		 3911 if (error == 0 && recursive && !ha->gotone)
3912 error = ENOENT;
3913
3914 if (error && error != EBUSY)
3915 (void) strlcpy(dsname, ha->failed, sizeof (ha->failed));
45d1cae3
BB		 3916
3917 dsl_sync_task_group_destroy(ha->dstg);
3918 kmem_free(ha, sizeof (struct dsl_ds_holdarg));
3919 spa_close(spa, FTAG);
428870ff
BB		 3920
3921 /*
3922 * We can get EBUSY if we were racing with deferred destroy and
3923 * dsl_dataset_user_release_check() hadn't done the necessary
3924 * open context setup. We can also get EBUSY if we're racing
3925 * with destroy and that thread is the ds_owner. Either way
3926 * the busy condition should be transient, and we should retry
3927 * the release operation.
3928 */
3929 if (error == EBUSY)
3930 goto top;
3931
45d1cae3
BB		 3932 return (error);
3933}
3934
428870ff 3935/*
572e2857
BB		 3936 * Called at spa_load time (with retry == B_FALSE) to release a stale
3937 * temporary user hold. Also called by the onexit code (with retry == B_TRUE).
428870ff
BB		 3938 */
3939int
572e2857
BB		 3940dsl_dataset_user_release_tmp(dsl_pool_t *dp, uint64_t dsobj, char *htag,
3941 boolean_t retry)
428870ff
BB		 3942{
3943 dsl_dataset_t *ds;
3944 char *snap;
3945 char *name;
3946 int namelen;
3947 int error;
3948
572e2857
BB		 3949 do {
3950 rw_enter(&dp->dp_config_rwlock, RW_READER);
3951 error = dsl_dataset_hold_obj(dp, dsobj, FTAG, &ds);
3952 rw_exit(&dp->dp_config_rwlock);
3953 if (error)
3954 return (error);
3955 namelen = dsl_dataset_namelen(ds)+1;
3956 name = kmem_alloc(namelen, KM_SLEEP);
3957 dsl_dataset_name(ds, name);
3958 dsl_dataset_rele(ds, FTAG);
428870ff 3959
572e2857
BB		 3960 snap = strchr(name, '@');
3961 *snap = '\0';
3962 ++snap;
3963 error = dsl_dataset_user_release(name, snap, htag, B_FALSE);
3964 kmem_free(name, namelen);
3965
3966 /*
3967 * The object can't have been destroyed because we have a hold,
3968 * but it might have been renamed, resulting in ENOENT. Retry
3969 * if we've been requested to do so.
3970 *
3971 * It would be nice if we could use the dsobj all the way
3972 * through and avoid ENOENT entirely. But we might need to
3973 * unmount the snapshot, and there's currently no way to lookup
3974 * a vfsp using a ZFS object id.
3975 */
3976 } while ((error == ENOENT) && retry);
3977
3978 return (error);
428870ff
BB		 3979}
3980
45d1cae3
BB		 3981int
3982dsl_dataset_get_holds(const char *dsname, nvlist_t **nvp)
3983{
3984 dsl_dataset_t *ds;
3985 int err;
3986
3987 err = dsl_dataset_hold(dsname, FTAG, &ds);
3988 if (err)
3989 return (err);
3990
3991 VERIFY(0 == nvlist_alloc(nvp, NV_UNIQUE_NAME, KM_SLEEP));
3992 if (ds->ds_phys->ds_userrefs_obj != 0) {
3993 zap_attribute_t *za;
3994 zap_cursor_t zc;
3995
3996 za = kmem_alloc(sizeof (zap_attribute_t), KM_SLEEP);
3997 for (zap_cursor_init(&zc, ds->ds_dir->dd_pool->dp_meta_objset,
3998 ds->ds_phys->ds_userrefs_obj);
3999 zap_cursor_retrieve(&zc, za) == 0;
4000 zap_cursor_advance(&zc)) {
4001 VERIFY(0 == nvlist_add_uint64(*nvp, za->za_name,
4002 za->za_first_integer));
4003 }
4004 zap_cursor_fini(&zc);
4005 kmem_free(za, sizeof (zap_attribute_t));
4006 }
4007 dsl_dataset_rele(ds, FTAG);
4008 return (0);
4009}
428870ff
BB		 4010
4011/*
4012 * Note, this fuction is used as the callback for dmu_objset_find(). We
4013 * always return 0 so that we will continue to find and process
4014 * inconsistent datasets, even if we encounter an error trying to
4015 * process one of them.
4016 */
4017/* ARGSUSED */
4018int
4019dsl_destroy_inconsistent(const char *dsname, void *arg)
4020{
4021 dsl_dataset_t *ds;
4022
4023 if (dsl_dataset_own(dsname, B_TRUE, FTAG, &ds) == 0) {
4024 if (DS_IS_INCONSISTENT(ds))
4025 (void) dsl_dataset_destroy(ds, FTAG, B_FALSE);
4026 else
4027 dsl_dataset_disown(ds, FTAG);
4028 }
4029 return (0);
4030}
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