include/sys/dsl_dataset.h

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