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.
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.
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]
22 * Copyright 2009 Sun Microsystems, Inc. All rights reserved.
23 * Use is subject to license terms.
29 #pragma ident "%Z%%M% %I% %E% SMI"
32 * This file describes the interface that the DMU provides for its
35 * The DMU also interacts with the SPA. That interface is described in
39 #include <sys/types.h>
40 #include <sys/param.h>
66 typedef struct objset objset_t;
67 typedef struct dmu_tx dmu_tx_t;
68 typedef struct dsl_dir dsl_dir_t;
70 typedef enum dmu_object_type {
73 DMU_OT_OBJECT_DIRECTORY, /* ZAP */
74 DMU_OT_OBJECT_ARRAY, /* UINT64 */
75 DMU_OT_PACKED_NVLIST, /* UINT8 (XDR by nvlist_pack/unpack) */
76 DMU_OT_PACKED_NVLIST_SIZE, /* UINT64 */
77 DMU_OT_BPLIST, /* UINT64 */
78 DMU_OT_BPLIST_HDR, /* UINT64 */
80 DMU_OT_SPACE_MAP_HEADER, /* UINT64 */
81 DMU_OT_SPACE_MAP, /* UINT64 */
83 DMU_OT_INTENT_LOG, /* UINT64 */
85 DMU_OT_DNODE, /* DNODE */
86 DMU_OT_OBJSET, /* OBJSET */
88 DMU_OT_DSL_DIR, /* UINT64 */
89 DMU_OT_DSL_DIR_CHILD_MAP, /* ZAP */
90 DMU_OT_DSL_DS_SNAP_MAP, /* ZAP */
91 DMU_OT_DSL_PROPS, /* ZAP */
92 DMU_OT_DSL_DATASET, /* UINT64 */
94 DMU_OT_ZNODE, /* ZNODE */
95 DMU_OT_OLDACL, /* Old ACL */
96 DMU_OT_PLAIN_FILE_CONTENTS, /* UINT8 */
97 DMU_OT_DIRECTORY_CONTENTS, /* ZAP */
98 DMU_OT_MASTER_NODE, /* ZAP */
99 DMU_OT_UNLINKED_SET, /* ZAP */
101 DMU_OT_ZVOL, /* UINT8 */
102 DMU_OT_ZVOL_PROP, /* ZAP */
103 /* other; for testing only! */
104 DMU_OT_PLAIN_OTHER, /* UINT8 */
105 DMU_OT_UINT64_OTHER, /* UINT64 */
106 DMU_OT_ZAP_OTHER, /* ZAP */
107 /* new object types: */
108 DMU_OT_ERROR_LOG, /* ZAP */
109 DMU_OT_SPA_HISTORY, /* UINT8 */
110 DMU_OT_SPA_HISTORY_OFFSETS, /* spa_his_phys_t */
111 DMU_OT_POOL_PROPS, /* ZAP */
112 DMU_OT_DSL_PERMS, /* ZAP */
113 DMU_OT_ACL, /* ACL */
114 DMU_OT_SYSACL, /* SYSACL */
115 DMU_OT_FUID, /* FUID table (Packed NVLIST UINT8) */
116 DMU_OT_FUID_SIZE, /* FUID table size UINT64 */
117 DMU_OT_NEXT_CLONES, /* ZAP */
118 DMU_OT_SCRUB_QUEUE, /* ZAP */
122 typedef enum dmu_objset_type {
127 DMU_OST_OTHER, /* For testing only! */
128 DMU_OST_ANY, /* Be careful! */
132 void byteswap_uint64_array(void *buf, size_t size);
133 void byteswap_uint32_array(void *buf, size_t size);
134 void byteswap_uint16_array(void *buf, size_t size);
135 void byteswap_uint8_array(void *buf, size_t size);
136 void zap_byteswap(void *buf, size_t size);
137 void zfs_oldacl_byteswap(void *buf, size_t size);
138 void zfs_acl_byteswap(void *buf, size_t size);
139 void zfs_znode_byteswap(void *buf, size_t size);
141 #define DS_MODE_NOHOLD 0 /* internal use only */
142 #define DS_MODE_USER 1 /* simple access, no special needs */
143 #define DS_MODE_OWNER 2 /* the "main" access, e.g. a mount */
144 #define DS_MODE_TYPE_MASK 0x3
145 #define DS_MODE_TYPE(x) ((x) & DS_MODE_TYPE_MASK)
146 #define DS_MODE_READONLY 0x8
147 #define DS_MODE_IS_READONLY(x) ((x) & DS_MODE_READONLY)
148 #define DS_MODE_INCONSISTENT 0x10
149 #define DS_MODE_IS_INCONSISTENT(x) ((x) & DS_MODE_INCONSISTENT)
151 #define DS_FIND_SNAPSHOTS (1<<0)
152 #define DS_FIND_CHILDREN (1<<1)
155 * The maximum number of bytes that can be accessed as part of one
156 * operation, including metadata.
158 #define DMU_MAX_ACCESS (10<<20) /* 10MB */
159 #define DMU_MAX_DELETEBLKCNT (20480) /* ~5MB of indirect blocks */
162 * Public routines to create, destroy, open, and close objsets.
164 int dmu_objset_open(const char *name, dmu_objset_type_t type, int mode,
166 int dmu_objset_open_ds(struct dsl_dataset *ds, dmu_objset_type_t type,
168 void dmu_objset_close(objset_t *os);
169 int dmu_objset_evict_dbufs(objset_t *os);
170 int dmu_objset_create(const char *name, dmu_objset_type_t type,
171 objset_t *clone_parent, uint64_t flags,
172 void (*func)(objset_t *os, void *arg, cred_t *cr, dmu_tx_t *tx), void *arg);
173 int dmu_objset_destroy(const char *name);
174 int dmu_snapshots_destroy(char *fsname, char *snapname);
175 int dmu_objset_rollback(objset_t *os);
176 int dmu_objset_snapshot(char *fsname, char *snapname, boolean_t recursive);
177 int dmu_objset_rename(const char *name, const char *newname,
178 boolean_t recursive);
179 int dmu_objset_find(char *name, int func(char *, void *), void *arg,
181 void dmu_objset_byteswap(void *buf, size_t size);
183 typedef struct dmu_buf {
184 uint64_t db_object; /* object that this buffer is part of */
185 uint64_t db_offset; /* byte offset in this object */
186 uint64_t db_size; /* size of buffer in bytes */
187 void *db_data; /* data in buffer */
190 typedef void dmu_buf_evict_func_t(struct dmu_buf *db, void *user_ptr);
193 * The names of zap entries in the DIRECTORY_OBJECT of the MOS.
195 #define DMU_POOL_DIRECTORY_OBJECT 1
196 #define DMU_POOL_CONFIG "config"
197 #define DMU_POOL_ROOT_DATASET "root_dataset"
198 #define DMU_POOL_SYNC_BPLIST "sync_bplist"
199 #define DMU_POOL_ERRLOG_SCRUB "errlog_scrub"
200 #define DMU_POOL_ERRLOG_LAST "errlog_last"
201 #define DMU_POOL_SPARES "spares"
202 #define DMU_POOL_DEFLATE "deflate"
203 #define DMU_POOL_HISTORY "history"
204 #define DMU_POOL_PROPS "pool_props"
205 #define DMU_POOL_L2CACHE "l2cache"
207 /* 4x8 zbookmark_t */
208 #define DMU_POOL_SCRUB_BOOKMARK "scrub_bookmark"
209 /* 1x8 zap obj DMU_OT_SCRUB_QUEUE */
210 #define DMU_POOL_SCRUB_QUEUE "scrub_queue"
212 #define DMU_POOL_SCRUB_MIN_TXG "scrub_min_txg"
214 #define DMU_POOL_SCRUB_MAX_TXG "scrub_max_txg"
215 /* 1x4 enum scrub_func */
216 #define DMU_POOL_SCRUB_FUNC "scrub_func"
218 #define DMU_POOL_SCRUB_ERRORS "scrub_errors"
221 * Allocate an object from this objset. The range of object numbers
222 * available is (0, DN_MAX_OBJECT). Object 0 is the meta-dnode.
224 * The transaction must be assigned to a txg. The newly allocated
225 * object will be "held" in the transaction (ie. you can modify the
226 * newly allocated object in this transaction).
228 * dmu_object_alloc() chooses an object and returns it in *objectp.
230 * dmu_object_claim() allocates a specific object number. If that
231 * number is already allocated, it fails and returns EEXIST.
233 * Return 0 on success, or ENOSPC or EEXIST as specified above.
235 uint64_t dmu_object_alloc(objset_t *os, dmu_object_type_t ot,
236 int blocksize, dmu_object_type_t bonus_type, int bonus_len, dmu_tx_t *tx);
237 int dmu_object_claim(objset_t *os, uint64_t object, dmu_object_type_t ot,
238 int blocksize, dmu_object_type_t bonus_type, int bonus_len, dmu_tx_t *tx);
239 int dmu_object_reclaim(objset_t *os, uint64_t object, dmu_object_type_t ot,
240 int blocksize, dmu_object_type_t bonustype, int bonuslen);
243 * Free an object from this objset.
245 * The object's data will be freed as well (ie. you don't need to call
246 * dmu_free(object, 0, -1, tx)).
248 * The object need not be held in the transaction.
250 * If there are any holds on this object's buffers (via dmu_buf_hold()),
251 * or tx holds on the object (via dmu_tx_hold_object()), you can not
252 * free it; it fails and returns EBUSY.
254 * If the object is not allocated, it fails and returns ENOENT.
256 * Return 0 on success, or EBUSY or ENOENT as specified above.
258 int dmu_object_free(objset_t *os, uint64_t object, dmu_tx_t *tx);
261 * Find the next allocated or free object.
263 * The objectp parameter is in-out. It will be updated to be the next
264 * object which is allocated. Ignore objects which have not been
265 * modified since txg.
267 * XXX Can only be called on a objset with no dirty data.
269 * Returns 0 on success, or ENOENT if there are no more objects.
271 int dmu_object_next(objset_t *os, uint64_t *objectp,
272 boolean_t hole, uint64_t txg);
275 * Set the data blocksize for an object.
277 * The object cannot have any blocks allcated beyond the first. If
278 * the first block is allocated already, the new size must be greater
279 * than the current block size. If these conditions are not met,
280 * ENOTSUP will be returned.
282 * Returns 0 on success, or EBUSY if there are any holds on the object
283 * contents, or ENOTSUP as described above.
285 int dmu_object_set_blocksize(objset_t *os, uint64_t object, uint64_t size,
286 int ibs, dmu_tx_t *tx);
289 * Set the checksum property on a dnode. The new checksum algorithm will
290 * apply to all newly written blocks; existing blocks will not be affected.
292 void dmu_object_set_checksum(objset_t *os, uint64_t object, uint8_t checksum,
296 * Set the compress property on a dnode. The new compression algorithm will
297 * apply to all newly written blocks; existing blocks will not be affected.
299 void dmu_object_set_compress(objset_t *os, uint64_t object, uint8_t compress,
303 * Decide how many copies of a given block we should make. Can be from
304 * 1 to SPA_DVAS_PER_BP.
306 int dmu_get_replication_level(struct objset_impl *, struct zbookmark *zb,
307 dmu_object_type_t ot);
309 * The bonus data is accessed more or less like a regular buffer.
310 * You must dmu_bonus_hold() to get the buffer, which will give you a
311 * dmu_buf_t with db_offset==-1ULL, and db_size = the size of the bonus
312 * data. As with any normal buffer, you must call dmu_buf_read() to
313 * read db_data, dmu_buf_will_dirty() before modifying it, and the
314 * object must be held in an assigned transaction before calling
315 * dmu_buf_will_dirty. You may use dmu_buf_set_user() on the bonus
316 * buffer as well. You must release your hold with dmu_buf_rele().
318 int dmu_bonus_hold(objset_t *os, uint64_t object, void *tag, dmu_buf_t **);
319 int dmu_bonus_max(void);
320 int dmu_set_bonus(dmu_buf_t *, int, dmu_tx_t *);
323 * Obtain the DMU buffer from the specified object which contains the
324 * specified offset. dmu_buf_hold() puts a "hold" on the buffer, so
325 * that it will remain in memory. You must release the hold with
326 * dmu_buf_rele(). You musn't access the dmu_buf_t after releasing your
327 * hold. You must have a hold on any dmu_buf_t* you pass to the DMU.
329 * You must call dmu_buf_read, dmu_buf_will_dirty, or dmu_buf_will_fill
330 * on the returned buffer before reading or writing the buffer's
331 * db_data. The comments for those routines describe what particular
332 * operations are valid after calling them.
334 * The object number must be a valid, allocated object number.
336 int dmu_buf_hold(objset_t *os, uint64_t object, uint64_t offset,
337 void *tag, dmu_buf_t **);
338 void dmu_buf_add_ref(dmu_buf_t *db, void* tag);
339 void dmu_buf_rele(dmu_buf_t *db, void *tag);
340 uint64_t dmu_buf_refcount(dmu_buf_t *db);
343 * dmu_buf_hold_array holds the DMU buffers which contain all bytes in a
344 * range of an object. A pointer to an array of dmu_buf_t*'s is
345 * returned (in *dbpp).
347 * dmu_buf_rele_array releases the hold on an array of dmu_buf_t*'s, and
348 * frees the array. The hold on the array of buffers MUST be released
349 * with dmu_buf_rele_array. You can NOT release the hold on each buffer
350 * individually with dmu_buf_rele.
352 int dmu_buf_hold_array_by_bonus(dmu_buf_t *db, uint64_t offset,
353 uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp);
354 void dmu_buf_rele_array(dmu_buf_t **, int numbufs, void *tag);
357 * Returns NULL on success, or the existing user ptr if it's already
360 * user_ptr is for use by the user and can be obtained via dmu_buf_get_user().
362 * user_data_ptr_ptr should be NULL, or a pointer to a pointer which
363 * will be set to db->db_data when you are allowed to access it. Note
364 * that db->db_data (the pointer) can change when you do dmu_buf_read(),
365 * dmu_buf_tryupgrade(), dmu_buf_will_dirty(), or dmu_buf_will_fill().
366 * *user_data_ptr_ptr will be set to the new value when it changes.
368 * If non-NULL, pageout func will be called when this buffer is being
369 * excised from the cache, so that you can clean up the data structure
370 * pointed to by user_ptr.
372 * dmu_evict_user() will call the pageout func for all buffers in a
373 * objset with a given pageout func.
375 void *dmu_buf_set_user(dmu_buf_t *db, void *user_ptr, void *user_data_ptr_ptr,
376 dmu_buf_evict_func_t *pageout_func);
378 * set_user_ie is the same as set_user, but request immediate eviction
379 * when hold count goes to zero.
381 void *dmu_buf_set_user_ie(dmu_buf_t *db, void *user_ptr,
382 void *user_data_ptr_ptr, dmu_buf_evict_func_t *pageout_func);
383 void *dmu_buf_update_user(dmu_buf_t *db_fake, void *old_user_ptr,
384 void *user_ptr, void *user_data_ptr_ptr,
385 dmu_buf_evict_func_t *pageout_func);
386 void dmu_evict_user(objset_t *os, dmu_buf_evict_func_t *func);
389 * Returns the user_ptr set with dmu_buf_set_user(), or NULL if not set.
391 void *dmu_buf_get_user(dmu_buf_t *db);
394 * Indicate that you are going to modify the buffer's data (db_data).
396 * The transaction (tx) must be assigned to a txg (ie. you've called
397 * dmu_tx_assign()). The buffer's object must be held in the tx
398 * (ie. you've called dmu_tx_hold_object(tx, db->db_object)).
400 void dmu_buf_will_dirty(dmu_buf_t *db, dmu_tx_t *tx);
403 * You must create a transaction, then hold the objects which you will
404 * (or might) modify as part of this transaction. Then you must assign
405 * the transaction to a transaction group. Once the transaction has
406 * been assigned, you can modify buffers which belong to held objects as
407 * part of this transaction. You can't modify buffers before the
408 * transaction has been assigned; you can't modify buffers which don't
409 * belong to objects which this transaction holds; you can't hold
410 * objects once the transaction has been assigned. You may hold an
411 * object which you are going to free (with dmu_object_free()), but you
414 * You can abort the transaction before it has been assigned.
416 * Note that you may hold buffers (with dmu_buf_hold) at any time,
417 * regardless of transaction state.
420 #define DMU_NEW_OBJECT (-1ULL)
421 #define DMU_OBJECT_END (-1ULL)
423 dmu_tx_t *dmu_tx_create(objset_t *os);
424 void dmu_tx_hold_write(dmu_tx_t *tx, uint64_t object, uint64_t off, int len);
425 void dmu_tx_hold_free(dmu_tx_t *tx, uint64_t object, uint64_t off,
427 void dmu_tx_hold_zap(dmu_tx_t *tx, uint64_t object, int add, char *name);
428 void dmu_tx_hold_bonus(dmu_tx_t *tx, uint64_t object);
429 void dmu_tx_abort(dmu_tx_t *tx);
430 int dmu_tx_assign(dmu_tx_t *tx, uint64_t txg_how);
431 void dmu_tx_wait(dmu_tx_t *tx);
432 void dmu_tx_commit(dmu_tx_t *tx);
435 * Free up the data blocks for a defined range of a file. If size is
436 * zero, the range from offset to end-of-file is freed.
438 int dmu_free_range(objset_t *os, uint64_t object, uint64_t offset,
439 uint64_t size, dmu_tx_t *tx);
440 int dmu_free_long_range(objset_t *os, uint64_t object, uint64_t offset,
442 int dmu_free_object(objset_t *os, uint64_t object);
445 * Convenience functions.
447 * Canfail routines will return 0 on success, or an errno if there is a
448 * nonrecoverable I/O error.
450 int dmu_read(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
452 void dmu_write(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
453 const void *buf, dmu_tx_t *tx);
454 int dmu_read_uio(objset_t *os, uint64_t object, struct uio *uio, uint64_t size);
455 int dmu_write_uio(objset_t *os, uint64_t object, struct uio *uio, uint64_t size,
457 int dmu_write_pages(objset_t *os, uint64_t object, uint64_t offset,
458 uint64_t size, struct page *pp, dmu_tx_t *tx);
460 extern int zfs_prefetch_disable;
463 * Asynchronously try to read in the data.
465 void dmu_prefetch(objset_t *os, uint64_t object, uint64_t offset,
468 typedef struct dmu_object_info {
469 /* All sizes are in bytes. */
470 uint32_t doi_data_block_size;
471 uint32_t doi_metadata_block_size;
472 uint64_t doi_bonus_size;
473 dmu_object_type_t doi_type;
474 dmu_object_type_t doi_bonus_type;
475 uint8_t doi_indirection; /* 2 = dnode->indirect->data */
476 uint8_t doi_checksum;
477 uint8_t doi_compress;
479 /* Values below are number of 512-byte blocks. */
480 uint64_t doi_physical_blks; /* data + metadata */
481 uint64_t doi_max_block_offset;
484 typedef void arc_byteswap_func_t(void *buf, size_t size);
486 typedef struct dmu_object_type_info {
487 arc_byteswap_func_t *ot_byteswap;
488 boolean_t ot_metadata;
490 } dmu_object_type_info_t;
492 extern const dmu_object_type_info_t dmu_ot[DMU_OT_NUMTYPES];
495 * Get information on a DMU object.
497 * Return 0 on success or ENOENT if object is not allocated.
499 * If doi is NULL, just indicates whether the object exists.
501 int dmu_object_info(objset_t *os, uint64_t object, dmu_object_info_t *doi);
502 void dmu_object_info_from_dnode(struct dnode *dn, dmu_object_info_t *doi);
503 void dmu_object_info_from_db(dmu_buf_t *db, dmu_object_info_t *doi);
504 void dmu_object_size_from_db(dmu_buf_t *db, uint32_t *blksize,
505 u_longlong_t *nblk512);
507 typedef struct dmu_objset_stats {
508 uint64_t dds_num_clones; /* number of clones of this */
509 uint64_t dds_creation_txg;
511 dmu_objset_type_t dds_type;
512 uint8_t dds_is_snapshot;
513 uint8_t dds_inconsistent;
514 char dds_origin[MAXNAMELEN];
515 } dmu_objset_stats_t;
518 * Get stats on a dataset.
520 void dmu_objset_fast_stat(objset_t *os, dmu_objset_stats_t *stat);
523 * Add entries to the nvlist for all the objset's properties. See
524 * zfs_prop_table[] and zfs(1m) for details on the properties.
526 void dmu_objset_stats(objset_t *os, struct nvlist *nv);
529 * Get the space usage statistics for statvfs().
531 * refdbytes is the amount of space "referenced" by this objset.
532 * availbytes is the amount of space available to this objset, taking
533 * into account quotas & reservations, assuming that no other objsets
534 * use the space first. These values correspond to the 'referenced' and
535 * 'available' properties, described in the zfs(1m) manpage.
537 * usedobjs and availobjs are the number of objects currently allocated,
540 void dmu_objset_space(objset_t *os, uint64_t *refdbytesp, uint64_t *availbytesp,
541 uint64_t *usedobjsp, uint64_t *availobjsp);
544 * The fsid_guid is a 56-bit ID that can change to avoid collisions.
545 * (Contrast with the ds_guid which is a 64-bit ID that will never
546 * change, so there is a small probability that it will collide.)
548 uint64_t dmu_objset_fsid_guid(objset_t *os);
550 int dmu_objset_is_snapshot(objset_t *os);
552 extern struct spa *dmu_objset_spa(objset_t *os);
553 extern struct zilog *dmu_objset_zil(objset_t *os);
554 extern struct dsl_pool *dmu_objset_pool(objset_t *os);
555 extern struct dsl_dataset *dmu_objset_ds(objset_t *os);
556 extern void dmu_objset_name(objset_t *os, char *buf);
557 extern dmu_objset_type_t dmu_objset_type(objset_t *os);
558 extern uint64_t dmu_objset_id(objset_t *os);
559 extern int dmu_snapshot_list_next(objset_t *os, int namelen, char *name,
560 uint64_t *id, uint64_t *offp, boolean_t *case_conflict);
561 extern int dmu_snapshot_realname(objset_t *os, char *name, char *real,
562 int maxlen, boolean_t *conflict);
563 extern int dmu_dir_list_next(objset_t *os, int namelen, char *name,
564 uint64_t *idp, uint64_t *offp);
565 extern void dmu_objset_set_user(objset_t *os, void *user_ptr);
566 extern void *dmu_objset_get_user(objset_t *os);
569 * Return the txg number for the given assigned transaction.
571 uint64_t dmu_tx_get_txg(dmu_tx_t *tx);
575 * If a parent zio is provided this function initiates a write on the
576 * provided buffer as a child of the parent zio.
577 * In the absence of a parent zio, the write is completed synchronously.
578 * At write completion, blk is filled with the bp of the written block.
579 * Note that while the data covered by this function will be on stable
580 * storage when the write completes this new data does not become a
581 * permanent part of the file until the associated transaction commits.
583 typedef void dmu_sync_cb_t(dmu_buf_t *db, void *arg);
584 int dmu_sync(struct zio *zio, dmu_buf_t *db,
585 struct blkptr *bp, uint64_t txg, dmu_sync_cb_t *done, void *arg);
588 * Find the next hole or data block in file starting at *off
589 * Return found offset in *off. Return ESRCH for end of file.
591 int dmu_offset_next(objset_t *os, uint64_t object, boolean_t hole,
595 * Initial setup and final teardown.
597 extern void dmu_init(void);
598 extern void dmu_fini(void);
600 typedef void (*dmu_traverse_cb_t)(objset_t *os, void *arg, struct blkptr *bp,
601 uint64_t object, uint64_t offset, int len);
602 void dmu_traverse_objset(objset_t *os, uint64_t txg_start,
603 dmu_traverse_cb_t cb, void *arg);
605 int dmu_sendbackup(objset_t *tosnap, objset_t *fromsnap, boolean_t fromorigin,
606 struct file *fp, offset_t *off);
608 typedef struct dmu_recv_cookie {
610 * This structure is opaque!
612 * If logical and real are different, we are recving the stream
613 * into the "real" temporary clone, and then switching it with
614 * the "logical" target.
616 struct dsl_dataset *drc_logical_ds;
617 struct dsl_dataset *drc_real_ds;
618 struct drr_begin *drc_drrb;
624 int dmu_recv_begin(char *tofs, char *tosnap, struct drr_begin *,
625 boolean_t force, objset_t *origin, boolean_t online, dmu_recv_cookie_t *);
626 int dmu_recv_stream(dmu_recv_cookie_t *drc, struct file *fp, offset_t *voffp);
627 int dmu_recv_end(dmu_recv_cookie_t *drc);
628 void dmu_recv_abort_cleanup(dmu_recv_cookie_t *drc);
631 #define ZFS_CRC64_POLY 0xC96C5795D7870F42ULL /* ECMA-182, reflected form */
632 extern uint64_t zfs_crc64_table[256];
638 #endif /* _SYS_DMU_H */