xref: /illumos-gate/usr/src/uts/common/fs/zfs/sys/dsl_dataset.h (revision a99cb9618990662acbd3bab1b4a5b05a6ca62556)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
23  * Copyright (c) 2011, 2017 by Delphix. All rights reserved.
24  * Copyright (c) 2013, Joyent, Inc. All rights reserved.
25  * Copyright (c) 2013 Steven Hartland. All rights reserved.
26  * Copyright (c) 2014 Spectra Logic Corporation, All rights reserved.
27  * Copyright (c) 2014 Integros [integros.com]
28  */
29 
30 #ifndef	_SYS_DSL_DATASET_H
31 #define	_SYS_DSL_DATASET_H
32 
33 #include <sys/dmu.h>
34 #include <sys/spa.h>
35 #include <sys/txg.h>
36 #include <sys/zio.h>
37 #include <sys/bplist.h>
38 #include <sys/dsl_synctask.h>
39 #include <sys/zfs_context.h>
40 #include <sys/dsl_deadlist.h>
41 #include <sys/refcount.h>
42 #include <sys/rrwlock.h>
43 #include <sys/dsl_crypt.h>
44 #include <zfeature_common.h>
45 
46 #ifdef	__cplusplus
47 extern "C" {
48 #endif
49 
50 struct dsl_dataset;
51 struct dsl_dir;
52 struct dsl_pool;
53 struct dsl_crypto_params;
54 struct dsl_key_mapping;
55 
56 #define	DS_FLAG_INCONSISTENT	(1ULL<<0)
57 #define	DS_IS_INCONSISTENT(ds)	\
58 	(dsl_dataset_phys(ds)->ds_flags & DS_FLAG_INCONSISTENT)
59 
60 /*
61  * Do not allow this dataset to be promoted.
62  */
63 #define	DS_FLAG_NOPROMOTE	(1ULL<<1)
64 
65 /*
66  * DS_FLAG_UNIQUE_ACCURATE is set if ds_unique_bytes has been correctly
67  * calculated for head datasets (starting with SPA_VERSION_UNIQUE_ACCURATE,
68  * refquota/refreservations).
69  */
70 #define	DS_FLAG_UNIQUE_ACCURATE	(1ULL<<2)
71 
72 /*
73  * DS_FLAG_DEFER_DESTROY is set after 'zfs destroy -d' has been called
74  * on a dataset. This allows the dataset to be destroyed using 'zfs release'.
75  */
76 #define	DS_FLAG_DEFER_DESTROY	(1ULL<<3)
77 #define	DS_IS_DEFER_DESTROY(ds)	\
78 	(dsl_dataset_phys(ds)->ds_flags & DS_FLAG_DEFER_DESTROY)
79 
80 /*
81  * DS_FIELD_* are strings that are used in the "extensified" dataset zap object.
82  * They should be of the format <reverse-dns>:<field>.
83  */
84 
85 /*
86  * This field's value is the object ID of a zap object which contains the
87  * bookmarks of this dataset.  If it is present, then this dataset is counted
88  * in the refcount of the SPA_FEATURES_BOOKMARKS feature.
89  */
90 #define	DS_FIELD_BOOKMARK_NAMES "com.delphix:bookmarks"
91 
92 /*
93  * This field is present (with value=0) if this dataset may contain large
94  * dnodes (>512B).  If it is present, then this dataset is counted in the
95  * refcount of the SPA_FEATURE_LARGE_DNODE feature.
96  */
97 #define	DS_FIELD_LARGE_DNODE "org.zfsonlinux:large_dnode"
98 
99 /*
100  * These fields are set on datasets that are in the middle of a resumable
101  * receive, and allow the sender to resume the send if it is interrupted.
102  */
103 #define	DS_FIELD_RESUME_FROMGUID "com.delphix:resume_fromguid"
104 #define	DS_FIELD_RESUME_TONAME "com.delphix:resume_toname"
105 #define	DS_FIELD_RESUME_TOGUID "com.delphix:resume_toguid"
106 #define	DS_FIELD_RESUME_OBJECT "com.delphix:resume_object"
107 #define	DS_FIELD_RESUME_OFFSET "com.delphix:resume_offset"
108 #define	DS_FIELD_RESUME_BYTES "com.delphix:resume_bytes"
109 #define	DS_FIELD_RESUME_LARGEBLOCK "com.delphix:resume_largeblockok"
110 #define	DS_FIELD_RESUME_EMBEDOK "com.delphix:resume_embedok"
111 #define	DS_FIELD_RESUME_COMPRESSOK "com.delphix:resume_compressok"
112 #define	DS_FIELD_RESUME_RAWOK "com.datto:resume_rawok"
113 
114 /*
115  * This field is set to the object number of the remap deadlist if one exists.
116  */
117 #define	DS_FIELD_REMAP_DEADLIST	"com.delphix:remap_deadlist"
118 
119 /*
120  * This field is set to the ivset guid for encrypted snapshots. This is used
121  * for validating raw receives.
122  */
123 #define	DS_FIELD_IVSET_GUID	"com.datto:ivset_guid"
124 
125 /*
126  * DS_FLAG_CI_DATASET is set if the dataset contains a file system whose
127  * name lookups should be performed case-insensitively.
128  */
129 #define	DS_FLAG_CI_DATASET	(1ULL<<16)
130 
131 #define	DS_CREATE_FLAG_NODIRTY	(1ULL<<24)
132 
133 typedef struct dsl_dataset_phys {
134 	uint64_t ds_dir_obj;		/* DMU_OT_DSL_DIR */
135 	uint64_t ds_prev_snap_obj;	/* DMU_OT_DSL_DATASET */
136 	uint64_t ds_prev_snap_txg;
137 	uint64_t ds_next_snap_obj;	/* DMU_OT_DSL_DATASET */
138 	uint64_t ds_snapnames_zapobj;	/* DMU_OT_DSL_DS_SNAP_MAP 0 for snaps */
139 	uint64_t ds_num_children;	/* clone/snap children; ==0 for head */
140 	uint64_t ds_creation_time;	/* seconds since 1970 */
141 	uint64_t ds_creation_txg;
142 	uint64_t ds_deadlist_obj;	/* DMU_OT_DEADLIST */
143 	/*
144 	 * ds_referenced_bytes, ds_compressed_bytes, and ds_uncompressed_bytes
145 	 * include all blocks referenced by this dataset, including those
146 	 * shared with any other datasets.
147 	 */
148 	uint64_t ds_referenced_bytes;
149 	uint64_t ds_compressed_bytes;
150 	uint64_t ds_uncompressed_bytes;
151 	uint64_t ds_unique_bytes;	/* only relevant to snapshots */
152 	/*
153 	 * The ds_fsid_guid is a 56-bit ID that can change to avoid
154 	 * collisions.  The ds_guid is a 64-bit ID that will never
155 	 * change, so there is a small probability that it will collide.
156 	 */
157 	uint64_t ds_fsid_guid;
158 	uint64_t ds_guid;
159 	uint64_t ds_flags;		/* DS_FLAG_* */
160 	blkptr_t ds_bp;
161 	uint64_t ds_next_clones_obj;	/* DMU_OT_DSL_CLONES */
162 	uint64_t ds_props_obj;		/* DMU_OT_DSL_PROPS for snaps */
163 	uint64_t ds_userrefs_obj;	/* DMU_OT_USERREFS */
164 	uint64_t ds_pad[5]; /* pad out to 320 bytes for good measure */
165 } dsl_dataset_phys_t;
166 
167 typedef struct dsl_dataset {
168 	dmu_buf_user_t ds_dbu;
169 	rrwlock_t ds_bp_rwlock; /* Protects ds_phys->ds_bp */
170 
171 	/* Immutable: */
172 	struct dsl_dir *ds_dir;
173 	dmu_buf_t *ds_dbuf;
174 	uint64_t ds_object;
175 	uint64_t ds_fsid_guid;
176 	boolean_t ds_is_snapshot;
177 	struct dsl_key_mapping *ds_key_mapping;
178 
179 	/* only used in syncing context, only valid for non-snapshots: */
180 	struct dsl_dataset *ds_prev;
181 	uint64_t ds_bookmarks;  /* DMU_OTN_ZAP_METADATA */
182 
183 	/* has internal locking: */
184 	dsl_deadlist_t ds_deadlist;
185 	bplist_t ds_pending_deadlist;
186 
187 	/*
188 	 * The remap deadlist contains blocks (DVA's, really) that are
189 	 * referenced by the previous snapshot and point to indirect vdevs,
190 	 * but in this dataset they have been remapped to point to concrete
191 	 * (or at least, less-indirect) vdevs.  In other words, the
192 	 * physical DVA is referenced by the previous snapshot but not by
193 	 * this dataset.  Logically, the DVA continues to be referenced,
194 	 * but we are using a different (less indirect) physical DVA.
195 	 * This deadlist is used to determine when physical DVAs that
196 	 * point to indirect vdevs are no longer referenced anywhere,
197 	 * and thus should be marked obsolete.
198 	 *
199 	 * This is only used if SPA_FEATURE_OBSOLETE_COUNTS is enabled.
200 	 */
201 	dsl_deadlist_t ds_remap_deadlist;
202 	/* protects creation of the ds_remap_deadlist */
203 	kmutex_t ds_remap_deadlist_lock;
204 
205 	/* protected by lock on pool's dp_dirty_datasets list */
206 	txg_node_t ds_dirty_link;
207 	list_node_t ds_synced_link;
208 
209 	/*
210 	 * ds_phys->ds_<accounting> is also protected by ds_lock.
211 	 * Protected by ds_lock:
212 	 */
213 	kmutex_t ds_lock;
214 	objset_t *ds_objset;
215 	uint64_t ds_userrefs;
216 	void *ds_owner;
217 
218 	/*
219 	 * Long holds prevent the ds from being destroyed; they allow the
220 	 * ds to remain held even after dropping the dp_config_rwlock.
221 	 * Owning counts as a long hold.  See the comments above
222 	 * dsl_pool_hold() for details.
223 	 */
224 	zfs_refcount_t ds_longholds;
225 
226 	/* no locking; only for making guesses */
227 	uint64_t ds_trysnap_txg;
228 
229 	/* for objset_open() */
230 	kmutex_t ds_opening_lock;
231 
232 	uint64_t ds_reserved;	/* cached refreservation */
233 	uint64_t ds_quota;	/* cached refquota */
234 
235 	kmutex_t ds_sendstream_lock;
236 	list_t ds_sendstreams;
237 
238 	/*
239 	 * When in the middle of a resumable receive, tracks how much
240 	 * progress we have made.
241 	 */
242 	uint64_t ds_resume_object[TXG_SIZE];
243 	uint64_t ds_resume_offset[TXG_SIZE];
244 	uint64_t ds_resume_bytes[TXG_SIZE];
245 
246 	/* Protected by our dsl_dir's dd_lock */
247 	list_t ds_prop_cbs;
248 
249 	/*
250 	 * For ZFEATURE_FLAG_PER_DATASET features, set if this dataset
251 	 * uses this feature.
252 	 */
253 	uint8_t ds_feature_inuse[SPA_FEATURES];
254 
255 	/*
256 	 * Set if we need to activate the feature on this dataset this txg
257 	 * (used only in syncing context).
258 	 */
259 	uint8_t ds_feature_activation_needed[SPA_FEATURES];
260 
261 	/* Protected by ds_lock; keep at end of struct for better locality */
262 	char ds_snapname[ZFS_MAX_DATASET_NAME_LEN];
263 } dsl_dataset_t;
264 
265 inline dsl_dataset_phys_t *
266 dsl_dataset_phys(dsl_dataset_t *ds)
267 {
268 	return (ds->ds_dbuf->db_data);
269 }
270 
271 typedef struct dsl_dataset_promote_arg {
272 	const char *ddpa_clonename;
273 	dsl_dataset_t *ddpa_clone;
274 	list_t shared_snaps, origin_snaps, clone_snaps;
275 	dsl_dataset_t *origin_origin; /* origin of the origin */
276 	uint64_t used, comp, uncomp, unique, cloneusedsnap, originusedsnap;
277 	nvlist_t *err_ds;
278 	cred_t *cr;
279 } dsl_dataset_promote_arg_t;
280 
281 typedef struct dsl_dataset_rollback_arg {
282 	const char *ddra_fsname;
283 	const char *ddra_tosnap;
284 	void *ddra_owner;
285 	nvlist_t *ddra_result;
286 } dsl_dataset_rollback_arg_t;
287 
288 typedef struct dsl_dataset_snapshot_arg {
289 	nvlist_t *ddsa_snaps;
290 	nvlist_t *ddsa_props;
291 	nvlist_t *ddsa_errors;
292 	cred_t *ddsa_cr;
293 } dsl_dataset_snapshot_arg_t;
294 
295 /*
296  * The max length of a temporary tag prefix is the number of hex digits
297  * required to express UINT64_MAX plus one for the hyphen.
298  */
299 #define	MAX_TAG_PREFIX_LEN	17
300 
301 #define	dsl_dataset_is_snapshot(ds) \
302 	(dsl_dataset_phys(ds)->ds_num_children != 0)
303 
304 #define	DS_UNIQUE_IS_ACCURATE(ds)	\
305 	((dsl_dataset_phys(ds)->ds_flags & DS_FLAG_UNIQUE_ACCURATE) != 0)
306 
307 /* flags for holding the dataset */
308 typedef enum ds_hold_flags {
309 	DS_HOLD_FLAG_DECRYPT    = 1 << 0 /* needs access to encrypted data */
310 } ds_hold_flags_t;
311 
312 int dsl_dataset_hold(struct dsl_pool *dp, const char *name, void *tag,
313     dsl_dataset_t **dsp);
314 int dsl_dataset_hold_flags(struct dsl_pool *dp, const char *name,
315     ds_hold_flags_t flags, void *tag, dsl_dataset_t **dsp);
316 boolean_t dsl_dataset_try_add_ref(struct dsl_pool *dp, dsl_dataset_t *ds,
317     void *tag);
318 int dsl_dataset_create_key_mapping(dsl_dataset_t *ds);
319 int dsl_dataset_hold_obj(struct dsl_pool *dp, uint64_t dsobj, void *tag,
320     dsl_dataset_t **);
321 int dsl_dataset_hold_obj_flags(struct dsl_pool *dp, uint64_t dsobj,
322 	ds_hold_flags_t flags, void *tag, dsl_dataset_t **);
323 void dsl_dataset_remove_key_mapping(dsl_dataset_t *ds);
324 void dsl_dataset_rele(dsl_dataset_t *ds, void *tag);
325 void dsl_dataset_rele_flags(dsl_dataset_t *ds, ds_hold_flags_t flags,
326     void *tag);
327 int dsl_dataset_own(struct dsl_pool *dp, const char *name,
328     ds_hold_flags_t flags, void *tag, dsl_dataset_t **dsp);
329 int dsl_dataset_own_obj(struct dsl_pool *dp, uint64_t dsobj,
330     ds_hold_flags_t flags, void *tag, dsl_dataset_t **dsp);
331 void dsl_dataset_disown(dsl_dataset_t *ds, ds_hold_flags_t flags, void *tag);
332 void dsl_dataset_name(dsl_dataset_t *ds, char *name);
333 boolean_t dsl_dataset_tryown(dsl_dataset_t *ds, void *tag);
334 int dsl_dataset_namelen(dsl_dataset_t *ds);
335 boolean_t dsl_dataset_has_owner(dsl_dataset_t *ds);
336 uint64_t dsl_dataset_create_sync(dsl_dir_t *pds, const char *lastname,
337     dsl_dataset_t *origin, uint64_t flags, cred_t *,
338     struct dsl_crypto_params *, dmu_tx_t *);
339 uint64_t dsl_dataset_create_sync_dd(dsl_dir_t *dd, dsl_dataset_t *origin,
340     struct dsl_crypto_params *dcp, uint64_t flags, dmu_tx_t *tx);
341 void dsl_dataset_snapshot_sync(void *arg, dmu_tx_t *tx);
342 int dsl_dataset_snapshot_check(void *arg, dmu_tx_t *tx);
343 int dsl_dataset_snapshot(nvlist_t *snaps, nvlist_t *props, nvlist_t *errors);
344 void dsl_dataset_promote_sync(void *arg, dmu_tx_t *tx);
345 int dsl_dataset_promote_check(void *arg, dmu_tx_t *tx);
346 int dsl_dataset_promote(const char *name, char *conflsnap);
347 int dsl_dataset_clone_swap(dsl_dataset_t *clone, dsl_dataset_t *origin_head,
348     boolean_t force);
349 int dsl_dataset_rename_snapshot(const char *fsname,
350     const char *oldsnapname, const char *newsnapname, boolean_t recursive);
351 int dsl_dataset_snapshot_tmp(const char *fsname, const char *snapname,
352     minor_t cleanup_minor, const char *htag);
353 
354 blkptr_t *dsl_dataset_get_blkptr(dsl_dataset_t *ds);
355 
356 spa_t *dsl_dataset_get_spa(dsl_dataset_t *ds);
357 
358 boolean_t dsl_dataset_modified_since_snap(dsl_dataset_t *ds,
359     dsl_dataset_t *snap);
360 
361 void dsl_dataset_sync(dsl_dataset_t *os, zio_t *zio, dmu_tx_t *tx);
362 void dsl_dataset_sync_done(dsl_dataset_t *os, dmu_tx_t *tx);
363 
364 void dsl_dataset_block_born(dsl_dataset_t *ds, const blkptr_t *bp,
365     dmu_tx_t *tx);
366 int dsl_dataset_block_kill(dsl_dataset_t *ds, const blkptr_t *bp,
367     dmu_tx_t *tx, boolean_t async);
368 void dsl_dataset_block_remapped(dsl_dataset_t *ds, uint64_t vdev,
369     uint64_t offset, uint64_t size, uint64_t birth, dmu_tx_t *tx);
370 
371 void dsl_dataset_dirty(dsl_dataset_t *ds, dmu_tx_t *tx);
372 
373 int get_clones_stat_impl(dsl_dataset_t *ds, nvlist_t *val);
374 char *get_receive_resume_stats_impl(dsl_dataset_t *ds);
375 char *get_child_receive_stats(dsl_dataset_t *ds);
376 uint64_t dsl_get_refratio(dsl_dataset_t *ds);
377 uint64_t dsl_get_logicalreferenced(dsl_dataset_t *ds);
378 uint64_t dsl_get_compressratio(dsl_dataset_t *ds);
379 uint64_t dsl_get_used(dsl_dataset_t *ds);
380 uint64_t dsl_get_creation(dsl_dataset_t *ds);
381 uint64_t dsl_get_creationtxg(dsl_dataset_t *ds);
382 uint64_t dsl_get_refquota(dsl_dataset_t *ds);
383 uint64_t dsl_get_refreservation(dsl_dataset_t *ds);
384 uint64_t dsl_get_guid(dsl_dataset_t *ds);
385 uint64_t dsl_get_unique(dsl_dataset_t *ds);
386 uint64_t dsl_get_objsetid(dsl_dataset_t *ds);
387 uint64_t dsl_get_userrefs(dsl_dataset_t *ds);
388 uint64_t dsl_get_defer_destroy(dsl_dataset_t *ds);
389 uint64_t dsl_get_referenced(dsl_dataset_t *ds);
390 uint64_t dsl_get_numclones(dsl_dataset_t *ds);
391 uint64_t dsl_get_inconsistent(dsl_dataset_t *ds);
392 uint64_t dsl_get_available(dsl_dataset_t *ds);
393 int dsl_get_written(dsl_dataset_t *ds, uint64_t *written);
394 int dsl_get_prev_snap(dsl_dataset_t *ds, char *snap);
395 int dsl_get_mountpoint(dsl_dataset_t *ds, const char *dsname, char *value,
396     char *source);
397 
398 void get_clones_stat(dsl_dataset_t *ds, nvlist_t *nv);
399 
400 void dsl_dataset_stats(dsl_dataset_t *os, nvlist_t *nv);
401 
402 void dsl_dataset_fast_stat(dsl_dataset_t *ds, dmu_objset_stats_t *stat);
403 void dsl_dataset_space(dsl_dataset_t *ds,
404     uint64_t *refdbytesp, uint64_t *availbytesp,
405     uint64_t *usedobjsp, uint64_t *availobjsp);
406 uint64_t dsl_dataset_fsid_guid(dsl_dataset_t *ds);
407 int dsl_dataset_space_written(dsl_dataset_t *oldsnap, dsl_dataset_t *new,
408     uint64_t *usedp, uint64_t *compp, uint64_t *uncompp);
409 int dsl_dataset_space_wouldfree(dsl_dataset_t *firstsnap, dsl_dataset_t *last,
410     uint64_t *usedp, uint64_t *compp, uint64_t *uncompp);
411 boolean_t dsl_dataset_is_dirty(dsl_dataset_t *ds);
412 
413 int dsl_dsobj_to_dsname(char *pname, uint64_t obj, char *buf);
414 
415 int dsl_dataset_check_quota(dsl_dataset_t *ds, boolean_t check_quota,
416     uint64_t asize, uint64_t inflight, uint64_t *used,
417     uint64_t *ref_rsrv);
418 int dsl_dataset_set_refquota(const char *dsname, zprop_source_t source,
419     uint64_t quota);
420 int dsl_dataset_set_refreservation(const char *dsname, zprop_source_t source,
421     uint64_t reservation);
422 
423 boolean_t dsl_dataset_is_before(dsl_dataset_t *later, dsl_dataset_t *earlier,
424     uint64_t earlier_txg);
425 void dsl_dataset_long_hold(dsl_dataset_t *ds, void *tag);
426 void dsl_dataset_long_rele(dsl_dataset_t *ds, void *tag);
427 boolean_t dsl_dataset_long_held(dsl_dataset_t *ds);
428 
429 int dsl_dataset_clone_swap_check_impl(dsl_dataset_t *clone,
430     dsl_dataset_t *origin_head, boolean_t force, void *owner, dmu_tx_t *tx);
431 void dsl_dataset_clone_swap_sync_impl(dsl_dataset_t *clone,
432     dsl_dataset_t *origin_head, dmu_tx_t *tx);
433 int dsl_dataset_snapshot_check_impl(dsl_dataset_t *ds, const char *snapname,
434     dmu_tx_t *tx, boolean_t recv, uint64_t cnt, cred_t *cr);
435 void dsl_dataset_snapshot_sync_impl(dsl_dataset_t *ds, const char *snapname,
436     dmu_tx_t *tx);
437 
438 void dsl_dataset_remove_from_next_clones(dsl_dataset_t *ds, uint64_t obj,
439     dmu_tx_t *tx);
440 void dsl_dataset_recalc_head_uniq(dsl_dataset_t *ds);
441 int dsl_dataset_get_snapname(dsl_dataset_t *ds);
442 int dsl_dataset_snap_lookup(dsl_dataset_t *ds, const char *name,
443     uint64_t *value);
444 int dsl_dataset_snap_remove(dsl_dataset_t *ds, const char *name, dmu_tx_t *tx,
445     boolean_t adj_cnt);
446 void dsl_dataset_set_refreservation_sync_impl(dsl_dataset_t *ds,
447     zprop_source_t source, uint64_t value, dmu_tx_t *tx);
448 void dsl_dataset_zapify(dsl_dataset_t *ds, dmu_tx_t *tx);
449 boolean_t dsl_dataset_is_zapified(dsl_dataset_t *ds);
450 boolean_t dsl_dataset_has_resume_receive_state(dsl_dataset_t *ds);
451 
452 int dsl_dataset_rollback_check(void *arg, dmu_tx_t *tx);
453 void dsl_dataset_rollback_sync(void *arg, dmu_tx_t *tx);
454 int dsl_dataset_rollback(const char *fsname, const char *tosnap, void *owner,
455     nvlist_t *result);
456 
457 uint64_t dsl_dataset_get_remap_deadlist_object(dsl_dataset_t *ds);
458 void dsl_dataset_create_remap_deadlist(dsl_dataset_t *ds, dmu_tx_t *tx);
459 boolean_t dsl_dataset_remap_deadlist_exists(dsl_dataset_t *ds);
460 void dsl_dataset_destroy_remap_deadlist(dsl_dataset_t *ds, dmu_tx_t *tx);
461 
462 void dsl_dataset_activate_feature(uint64_t dsobj,
463     spa_feature_t f, dmu_tx_t *tx);
464 void dsl_dataset_deactivate_feature(uint64_t dsobj,
465     spa_feature_t f, dmu_tx_t *tx);
466 
467 #ifdef ZFS_DEBUG
468 #define	dprintf_ds(ds, fmt, ...) do { \
469 	if (zfs_flags & ZFS_DEBUG_DPRINTF) { \
470 	char *__ds_name = kmem_alloc(ZFS_MAX_DATASET_NAME_LEN, KM_SLEEP); \
471 	dsl_dataset_name(ds, __ds_name); \
472 	dprintf("ds=%s " fmt, __ds_name, __VA_ARGS__); \
473 	kmem_free(__ds_name, ZFS_MAX_DATASET_NAME_LEN); \
474 	} \
475 _NOTE(CONSTCOND) } while (0)
476 #else
477 #define	dprintf_ds(dd, fmt, ...)
478 #endif
479 
480 #ifdef	__cplusplus
481 }
482 #endif
483 
484 #endif /* _SYS_DSL_DATASET_H */
485