Initial Linux ZFS GIT Repo
[zfs.git] / zfs / lib / libdmu-ctl / dmu_send.c
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 2008 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25
26 #pragma ident   "@(#)dmu_send.c 1.14    08/04/27 SMI"
27
28 #include <sys/dmu.h>
29 #include <sys/dmu_impl.h>
30 #include <sys/dmu_tx.h>
31 #include <sys/dbuf.h>
32 #include <sys/dnode.h>
33 #include <sys/zfs_context.h>
34 #include <sys/dmu_objset.h>
35 #include <sys/dmu_traverse.h>
36 #include <sys/dsl_dataset.h>
37 #include <sys/dsl_dir.h>
38 #include <sys/dsl_pool.h>
39 #include <sys/dsl_synctask.h>
40 #include <sys/zfs_ioctl.h>
41 #include <sys/zap.h>
42 #include <sys/zio_checksum.h>
43
44 static char *dmu_recv_tag = "dmu_recv_tag";
45
46 struct backuparg {
47         dmu_replay_record_t *drr;
48         vnode_t *vp;
49         offset_t *off;
50         objset_t *os;
51         zio_cksum_t zc;
52         int err;
53 };
54
55 static int
56 dump_bytes(struct backuparg *ba, void *buf, int len)
57 {
58         ssize_t resid; /* have to get resid to get detailed errno */
59         ASSERT3U(len % 8, ==, 0);
60
61         fletcher_4_incremental_native(buf, len, &ba->zc);
62         ba->err = vn_rdwr(UIO_WRITE, ba->vp,
63             (caddr_t)buf, len,
64             0, UIO_SYSSPACE, FAPPEND, RLIM64_INFINITY, CRED(), &resid);
65         *ba->off += len;
66         return (ba->err);
67 }
68
69 static int
70 dump_free(struct backuparg *ba, uint64_t object, uint64_t offset,
71     uint64_t length)
72 {
73         /* write a FREE record */
74         bzero(ba->drr, sizeof (dmu_replay_record_t));
75         ba->drr->drr_type = DRR_FREE;
76         ba->drr->drr_u.drr_free.drr_object = object;
77         ba->drr->drr_u.drr_free.drr_offset = offset;
78         ba->drr->drr_u.drr_free.drr_length = length;
79
80         if (dump_bytes(ba, ba->drr, sizeof (dmu_replay_record_t)))
81                 return (EINTR);
82         return (0);
83 }
84
85 static int
86 dump_data(struct backuparg *ba, dmu_object_type_t type,
87     uint64_t object, uint64_t offset, int blksz, void *data)
88 {
89         /* write a DATA record */
90         bzero(ba->drr, sizeof (dmu_replay_record_t));
91         ba->drr->drr_type = DRR_WRITE;
92         ba->drr->drr_u.drr_write.drr_object = object;
93         ba->drr->drr_u.drr_write.drr_type = type;
94         ba->drr->drr_u.drr_write.drr_offset = offset;
95         ba->drr->drr_u.drr_write.drr_length = blksz;
96
97         if (dump_bytes(ba, ba->drr, sizeof (dmu_replay_record_t)))
98                 return (EINTR);
99         if (dump_bytes(ba, data, blksz))
100                 return (EINTR);
101         return (0);
102 }
103
104 static int
105 dump_freeobjects(struct backuparg *ba, uint64_t firstobj, uint64_t numobjs)
106 {
107         /* write a FREEOBJECTS record */
108         bzero(ba->drr, sizeof (dmu_replay_record_t));
109         ba->drr->drr_type = DRR_FREEOBJECTS;
110         ba->drr->drr_u.drr_freeobjects.drr_firstobj = firstobj;
111         ba->drr->drr_u.drr_freeobjects.drr_numobjs = numobjs;
112
113         if (dump_bytes(ba, ba->drr, sizeof (dmu_replay_record_t)))
114                 return (EINTR);
115         return (0);
116 }
117
118 static int
119 dump_dnode(struct backuparg *ba, uint64_t object, dnode_phys_t *dnp)
120 {
121         if (dnp == NULL || dnp->dn_type == DMU_OT_NONE)
122                 return (dump_freeobjects(ba, object, 1));
123
124         /* write an OBJECT record */
125         bzero(ba->drr, sizeof (dmu_replay_record_t));
126         ba->drr->drr_type = DRR_OBJECT;
127         ba->drr->drr_u.drr_object.drr_object = object;
128         ba->drr->drr_u.drr_object.drr_type = dnp->dn_type;
129         ba->drr->drr_u.drr_object.drr_bonustype = dnp->dn_bonustype;
130         ba->drr->drr_u.drr_object.drr_blksz =
131             dnp->dn_datablkszsec << SPA_MINBLOCKSHIFT;
132         ba->drr->drr_u.drr_object.drr_bonuslen = dnp->dn_bonuslen;
133         ba->drr->drr_u.drr_object.drr_checksum = dnp->dn_checksum;
134         ba->drr->drr_u.drr_object.drr_compress = dnp->dn_compress;
135
136         if (dump_bytes(ba, ba->drr, sizeof (dmu_replay_record_t)))
137                 return (EINTR);
138
139         if (dump_bytes(ba, DN_BONUS(dnp), P2ROUNDUP(dnp->dn_bonuslen, 8)))
140                 return (EINTR);
141
142         /* free anything past the end of the file */
143         if (dump_free(ba, object, (dnp->dn_maxblkid + 1) *
144             (dnp->dn_datablkszsec << SPA_MINBLOCKSHIFT), -1ULL))
145                 return (EINTR);
146         if (ba->err)
147                 return (EINTR);
148         return (0);
149 }
150
151 #define BP_SPAN(dnp, level) \
152         (((uint64_t)dnp->dn_datablkszsec) << (SPA_MINBLOCKSHIFT + \
153         (level) * (dnp->dn_indblkshift - SPA_BLKPTRSHIFT)))
154
155 static int
156 backup_cb(traverse_blk_cache_t *bc, spa_t *spa, void *arg)
157 {
158         struct backuparg *ba = arg;
159         uint64_t object = bc->bc_bookmark.zb_object;
160         int level = bc->bc_bookmark.zb_level;
161         uint64_t blkid = bc->bc_bookmark.zb_blkid;
162         blkptr_t *bp = bc->bc_blkptr.blk_birth ? &bc->bc_blkptr : NULL;
163         dmu_object_type_t type = bp ? BP_GET_TYPE(bp) : DMU_OT_NONE;
164         void *data = bc->bc_data;
165         int err = 0;
166
167         if (issig(JUSTLOOKING) && issig(FORREAL))
168                 return (EINTR);
169
170         ASSERT(data || bp == NULL);
171
172         if (bp == NULL && object == 0) {
173                 uint64_t span = BP_SPAN(bc->bc_dnode, level);
174                 uint64_t dnobj = (blkid * span) >> DNODE_SHIFT;
175                 err = dump_freeobjects(ba, dnobj, span >> DNODE_SHIFT);
176         } else if (bp == NULL) {
177                 uint64_t span = BP_SPAN(bc->bc_dnode, level);
178                 err = dump_free(ba, object, blkid * span, span);
179         } else if (data && level == 0 && type == DMU_OT_DNODE) {
180                 dnode_phys_t *blk = data;
181                 int i;
182                 int blksz = BP_GET_LSIZE(bp);
183
184                 for (i = 0; i < blksz >> DNODE_SHIFT; i++) {
185                         uint64_t dnobj =
186                             (blkid << (DNODE_BLOCK_SHIFT - DNODE_SHIFT)) + i;
187                         err = dump_dnode(ba, dnobj, blk+i);
188                         if (err)
189                                 break;
190                 }
191         } else if (level == 0 &&
192             type != DMU_OT_DNODE && type != DMU_OT_OBJSET) {
193                 int blksz = BP_GET_LSIZE(bp);
194                 if (data == NULL) {
195                         uint32_t aflags = ARC_WAIT;
196                         arc_buf_t *abuf;
197                         zbookmark_t zb;
198
199                         zb.zb_objset = ba->os->os->os_dsl_dataset->ds_object;
200                         zb.zb_object = object;
201                         zb.zb_level = level;
202                         zb.zb_blkid = blkid;
203                         (void) arc_read(NULL, spa, bp,
204                             dmu_ot[type].ot_byteswap, arc_getbuf_func, &abuf,
205                             ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_MUSTSUCCEED,
206                             &aflags, &zb);
207
208                         if (abuf) {
209                                 err = dump_data(ba, type, object, blkid * blksz,
210                                     blksz, abuf->b_data);
211                                 (void) arc_buf_remove_ref(abuf, &abuf);
212                         }
213                 } else {
214                         err = dump_data(ba, type, object, blkid * blksz,
215                             blksz, data);
216                 }
217         }
218
219         ASSERT(err == 0 || err == EINTR);
220         return (err);
221 }
222
223 int
224 dmu_sendbackup(objset_t *tosnap, objset_t *fromsnap, boolean_t fromorigin,
225     vnode_t *vp, offset_t *off)
226 {
227         dsl_dataset_t *ds = tosnap->os->os_dsl_dataset;
228         dsl_dataset_t *fromds = fromsnap ? fromsnap->os->os_dsl_dataset : NULL;
229         dmu_replay_record_t *drr;
230         struct backuparg ba;
231         int err;
232         uint64_t fromtxg = 0;
233
234         /* tosnap must be a snapshot */
235         if (ds->ds_phys->ds_next_snap_obj == 0)
236                 return (EINVAL);
237
238         /* fromsnap must be an earlier snapshot from the same fs as tosnap */
239         if (fromds && (ds->ds_dir != fromds->ds_dir ||
240             fromds->ds_phys->ds_creation_txg >= ds->ds_phys->ds_creation_txg))
241                 return (EXDEV);
242
243         if (fromorigin) {
244                 if (fromsnap)
245                         return (EINVAL);
246
247                 if (ds->ds_dir->dd_phys->dd_origin_obj != NULL) {
248                         dsl_pool_t *dp = ds->ds_dir->dd_pool;
249                         rw_enter(&dp->dp_config_rwlock, RW_READER);
250                         err = dsl_dataset_open_obj(dp,
251                             ds->ds_dir->dd_phys->dd_origin_obj, NULL,
252                             DS_MODE_NONE, FTAG, &fromds);
253                         rw_exit(&dp->dp_config_rwlock);
254                         if (err)
255                                 return (err);
256                 } else {
257                         fromorigin = B_FALSE;
258                 }
259         }
260
261
262         drr = kmem_zalloc(sizeof (dmu_replay_record_t), KM_SLEEP);
263         drr->drr_type = DRR_BEGIN;
264         drr->drr_u.drr_begin.drr_magic = DMU_BACKUP_MAGIC;
265         drr->drr_u.drr_begin.drr_version = DMU_BACKUP_STREAM_VERSION;
266         drr->drr_u.drr_begin.drr_creation_time =
267             ds->ds_phys->ds_creation_time;
268         drr->drr_u.drr_begin.drr_type = tosnap->os->os_phys->os_type;
269         if (fromorigin)
270                 drr->drr_u.drr_begin.drr_flags |= DRR_FLAG_CLONE;
271         drr->drr_u.drr_begin.drr_toguid = ds->ds_phys->ds_guid;
272         if (ds->ds_phys->ds_flags & DS_FLAG_CI_DATASET)
273                 drr->drr_u.drr_begin.drr_flags |= DRR_FLAG_CI_DATA;
274
275         if (fromds)
276                 drr->drr_u.drr_begin.drr_fromguid = fromds->ds_phys->ds_guid;
277         dsl_dataset_name(ds, drr->drr_u.drr_begin.drr_toname);
278
279         if (fromds)
280                 fromtxg = fromds->ds_phys->ds_creation_txg;
281         if (fromorigin)
282                 dsl_dataset_close(fromds, DS_MODE_NONE, FTAG);
283
284         ba.drr = drr;
285         ba.vp = vp;
286         ba.os = tosnap;
287         ba.off = off;
288         ZIO_SET_CHECKSUM(&ba.zc, 0, 0, 0, 0);
289
290         if (dump_bytes(&ba, drr, sizeof (dmu_replay_record_t))) {
291                 kmem_free(drr, sizeof (dmu_replay_record_t));
292                 return (ba.err);
293         }
294
295         err = traverse_dsl_dataset(ds, fromtxg,
296             ADVANCE_PRE | ADVANCE_HOLES | ADVANCE_DATA | ADVANCE_NOLOCK,
297             backup_cb, &ba);
298
299         if (err) {
300                 if (err == EINTR && ba.err)
301                         err = ba.err;
302                 kmem_free(drr, sizeof (dmu_replay_record_t));
303                 return (err);
304         }
305
306         bzero(drr, sizeof (dmu_replay_record_t));
307         drr->drr_type = DRR_END;
308         drr->drr_u.drr_end.drr_checksum = ba.zc;
309
310         if (dump_bytes(&ba, drr, sizeof (dmu_replay_record_t))) {
311                 kmem_free(drr, sizeof (dmu_replay_record_t));
312                 return (ba.err);
313         }
314
315         kmem_free(drr, sizeof (dmu_replay_record_t));
316
317         return (0);
318 }
319
320 struct recvbeginsyncarg {
321         const char *tofs;
322         const char *tosnap;
323         dsl_dataset_t *origin;
324         uint64_t fromguid;
325         dmu_objset_type_t type;
326         void *tag;
327         boolean_t force;
328         uint64_t dsflags;
329         char clonelastname[MAXNAMELEN];
330         dsl_dataset_t *ds; /* the ds to recv into; returned from the syncfunc */
331 };
332
333 static dsl_dataset_t *
334 recv_full_sync_impl(dsl_pool_t *dp, uint64_t dsobj, dmu_objset_type_t type,
335     cred_t *cr, dmu_tx_t *tx)
336 {
337         dsl_dataset_t *ds;
338
339         VERIFY(0 == dsl_dataset_open_obj(dp, dsobj, NULL,
340             DS_MODE_EXCLUSIVE, dmu_recv_tag, &ds));
341
342         if (type != DMU_OST_NONE) {
343                 (void) dmu_objset_create_impl(dp->dp_spa,
344                     ds, &ds->ds_phys->ds_bp, type, tx);
345         }
346
347         spa_history_internal_log(LOG_DS_REPLAY_FULL_SYNC,
348             ds->ds_dir->dd_pool->dp_spa, tx, cr, "dataset = %lld",
349             ds->ds_phys->ds_dir_obj);
350
351         return (ds);
352 }
353
354 /* ARGSUSED */
355 static int
356 recv_full_check(void *arg1, void *arg2, dmu_tx_t *tx)
357 {
358         dsl_dir_t *dd = arg1;
359         struct recvbeginsyncarg *rbsa = arg2;
360         objset_t *mos = dd->dd_pool->dp_meta_objset;
361         uint64_t val;
362         int err;
363
364         err = zap_lookup(mos, dd->dd_phys->dd_child_dir_zapobj,
365             strrchr(rbsa->tofs, '/') + 1, sizeof (uint64_t), 1, &val);
366
367         if (err != ENOENT)
368                 return (err ? err : EEXIST);
369
370         if (rbsa->origin) {
371                 /* make sure it's a snap in the same pool */
372                 if (rbsa->origin->ds_dir->dd_pool != dd->dd_pool)
373                         return (EXDEV);
374                 if (rbsa->origin->ds_phys->ds_num_children == 0)
375                         return (EINVAL);
376                 if (rbsa->origin->ds_phys->ds_guid != rbsa->fromguid)
377                         return (ENODEV);
378         }
379
380         return (0);
381 }
382
383 static void
384 recv_full_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx)
385 {
386         dsl_dir_t *dd = arg1;
387         struct recvbeginsyncarg *rbsa = arg2;
388         uint64_t dsobj;
389         uint64_t flags = DS_FLAG_INCONSISTENT;
390
391         flags |= rbsa->dsflags;
392
393         dsobj = dsl_dataset_create_sync(dd, strrchr(rbsa->tofs, '/') + 1,
394             rbsa->origin, flags, cr, tx);
395
396         rbsa->ds = recv_full_sync_impl(dd->dd_pool, dsobj,
397             rbsa->origin ? DMU_OST_NONE : rbsa->type, cr, tx);
398 }
399
400 static int
401 recv_full_existing_check(void *arg1, void *arg2, dmu_tx_t *tx)
402 {
403         dsl_dataset_t *ds = arg1;
404         struct recvbeginsyncarg *rbsa = arg2;
405         int err;
406
407         /* must be a head ds */
408         if (ds->ds_phys->ds_next_snap_obj != 0)
409                 return (EINVAL);
410
411         /* must not be a clone ds */
412         if (ds->ds_prev != NULL)
413                 return (EINVAL);
414
415         err = dsl_dataset_destroy_check(ds, rbsa->tag, tx);
416         if (err)
417                 return (err);
418
419         if (rbsa->origin) {
420                 /* make sure it's a snap in the same pool */
421                 if (rbsa->origin->ds_dir->dd_pool != ds->ds_dir->dd_pool)
422                         return (EXDEV);
423                 if (rbsa->origin->ds_phys->ds_num_children == 0)
424                         return (EINVAL);
425                 if (rbsa->origin->ds_phys->ds_guid != rbsa->fromguid)
426                         return (ENODEV);
427         }
428
429         return (0);
430 }
431
432 static void
433 recv_full_existing_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx)
434 {
435         dsl_dataset_t *ds = arg1;
436         struct recvbeginsyncarg *rbsa = arg2;
437         dsl_dir_t *dd = ds->ds_dir;
438         uint64_t dsobj;
439         uint64_t flags = DS_FLAG_INCONSISTENT;
440
441         flags |= rbsa->dsflags;
442
443         /*
444          * NB: caller must provide an extra hold on the dsl_dir_t, so it
445          * won't go away when dsl_dataset_destroy_sync() closes the
446          * dataset.
447          */
448         dsl_dataset_destroy_sync(ds, rbsa->tag, cr, tx);
449
450         dsobj = dsl_dataset_create_sync_impl(dd, rbsa->origin, flags, tx);
451
452         rbsa->ds = recv_full_sync_impl(dd->dd_pool, dsobj,
453             rbsa->origin ? DMU_OST_NONE : rbsa->type, cr, tx);
454 }
455
456 /* ARGSUSED */
457 static int
458 recv_incremental_check(void *arg1, void *arg2, dmu_tx_t *tx)
459 {
460         dsl_dataset_t *ds = arg1;
461         struct recvbeginsyncarg *rbsa = arg2;
462         int err;
463         uint64_t val;
464
465         /* must not have any changes since most recent snapshot */
466         if (!rbsa->force && dsl_dataset_modified_since_lastsnap(ds))
467                 return (ETXTBSY);
468
469         /* must already be a snapshot of this fs */
470         if (ds->ds_phys->ds_prev_snap_obj == 0)
471                 return (ENODEV);
472
473         /* most recent snapshot must match fromguid */
474         if (ds->ds_prev->ds_phys->ds_guid != rbsa->fromguid)
475                 return (ENODEV);
476
477         /* temporary clone name must not exist */
478         err = zap_lookup(ds->ds_dir->dd_pool->dp_meta_objset,
479             ds->ds_dir->dd_phys->dd_child_dir_zapobj,
480             rbsa->clonelastname, 8, 1, &val);
481         if (err == 0)
482                 return (EEXIST);
483         if (err != ENOENT)
484                 return (err);
485
486         /* new snapshot name must not exist */
487         err = zap_lookup(ds->ds_dir->dd_pool->dp_meta_objset,
488             ds->ds_phys->ds_snapnames_zapobj, rbsa->tosnap, 8, 1, &val);
489         if (err == 0)
490                 return (EEXIST);
491         if (err != ENOENT)
492                 return (err);
493         return (0);
494 }
495
496 /* ARGSUSED */
497 static void
498 recv_online_incremental_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx)
499 {
500         dsl_dataset_t *ohds = arg1;
501         struct recvbeginsyncarg *rbsa = arg2;
502         dsl_pool_t *dp = ohds->ds_dir->dd_pool;
503         dsl_dataset_t *ods, *cds;
504         uint64_t dsobj;
505         uint64_t flags = DS_FLAG_INCONSISTENT;
506
507         flags |= rbsa->dsflags;
508
509         /* create the temporary clone */
510         VERIFY(0 == dsl_dataset_open_obj(dp, ohds->ds_phys->ds_prev_snap_obj,
511             NULL, DS_MODE_STANDARD, FTAG, &ods));
512         dsobj = dsl_dataset_create_sync(ohds->ds_dir,
513             rbsa->clonelastname, ods, flags, cr, tx);
514         dsl_dataset_close(ods, DS_MODE_STANDARD, FTAG);
515
516         /* open the temporary clone */
517         VERIFY(0 == dsl_dataset_open_obj(dp, dsobj, NULL,
518             DS_MODE_EXCLUSIVE, dmu_recv_tag, &cds));
519
520         /* copy the refquota from the target fs to the clone */
521         if (ohds->ds_quota > 0)
522                 dsl_dataset_set_quota_sync(cds, &ohds->ds_quota, cr, tx);
523
524         rbsa->ds = cds;
525
526         spa_history_internal_log(LOG_DS_REPLAY_INC_SYNC,
527             dp->dp_spa, tx, cr, "dataset = %lld",
528             cds->ds_phys->ds_dir_obj);
529 }
530
531 /* ARGSUSED */
532 static void
533 recv_offline_incremental_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx)
534 {
535         dsl_dataset_t *ds = arg1;
536
537         dmu_buf_will_dirty(ds->ds_dbuf, tx);
538         ds->ds_phys->ds_flags |= DS_FLAG_INCONSISTENT;
539
540         spa_history_internal_log(LOG_DS_REPLAY_INC_SYNC,
541             ds->ds_dir->dd_pool->dp_spa, tx, cr, "dataset = %lld",
542             ds->ds_phys->ds_dir_obj);
543 }
544
545 /*
546  * NB: callers *MUST* call dmu_recv_stream() if dmu_recv_begin()
547  * succeeds; otherwise we will leak the holds on the datasets.
548  */
549 int
550 dmu_recv_begin(char *tofs, char *tosnap, struct drr_begin *drrb,
551     boolean_t force, objset_t *origin, boolean_t online, dmu_recv_cookie_t *drc)
552 {
553         int err = 0;
554         boolean_t byteswap;
555         struct recvbeginsyncarg rbsa;
556         uint64_t version;
557         int flags;
558         dsl_dataset_t *ds;
559
560         if (drrb->drr_magic == DMU_BACKUP_MAGIC)
561                 byteswap = FALSE;
562         else if (drrb->drr_magic == BSWAP_64(DMU_BACKUP_MAGIC))
563                 byteswap = TRUE;
564         else
565                 return (EINVAL);
566
567         rbsa.tofs = tofs;
568         rbsa.tosnap = tosnap;
569         rbsa.origin = origin ? origin->os->os_dsl_dataset : NULL;
570         rbsa.fromguid = drrb->drr_fromguid;
571         rbsa.type = drrb->drr_type;
572         rbsa.tag = FTAG;
573         rbsa.dsflags = 0;
574         version = drrb->drr_version;
575         flags = drrb->drr_flags;
576
577         if (byteswap) {
578                 rbsa.type = BSWAP_32(rbsa.type);
579                 rbsa.fromguid = BSWAP_64(rbsa.fromguid);
580                 version = BSWAP_64(version);
581                 flags = BSWAP_32(flags);
582         }
583
584         if (version != DMU_BACKUP_STREAM_VERSION ||
585             rbsa.type >= DMU_OST_NUMTYPES ||
586             ((flags & DRR_FLAG_CLONE) && origin == NULL))
587                 return (EINVAL);
588
589         if (flags & DRR_FLAG_CI_DATA)
590                 rbsa.dsflags = DS_FLAG_CI_DATASET;
591
592         bzero(drc, sizeof (dmu_recv_cookie_t));
593         drc->drc_drrb = drrb;
594         drc->drc_tosnap = tosnap;
595         drc->drc_force = force;
596
597         /*
598          * Process the begin in syncing context.
599          */
600         if (rbsa.fromguid && !(flags & DRR_FLAG_CLONE) && !online) {
601                 /* offline incremental receive */
602                 err = dsl_dataset_open(tofs,
603                     DS_MODE_EXCLUSIVE, dmu_recv_tag, &ds);
604                 if (err)
605                         return (err);
606
607                 /*
608                  * Only do the rollback if the most recent snapshot
609                  * matches the incremental source
610                  */
611                 if (force) {
612                         if (ds->ds_prev == NULL ||
613                             ds->ds_prev->ds_phys->ds_guid !=
614                             rbsa.fromguid) {
615                                 dsl_dataset_close(ds, DS_MODE_EXCLUSIVE,
616                                     dmu_recv_tag);
617                                 return (ENODEV);
618                         }
619                         (void) dsl_dataset_rollback(ds, DMU_OST_NONE);
620                 }
621                 rbsa.force = B_FALSE;
622                 err = dsl_sync_task_do(ds->ds_dir->dd_pool,
623                     recv_incremental_check,
624                     recv_offline_incremental_sync,
625                     ds, &rbsa, 1);
626                 if (err) {
627                         dsl_dataset_close(ds, DS_MODE_EXCLUSIVE, dmu_recv_tag);
628                         return (err);
629                 }
630                 drc->drc_logical_ds = drc->drc_real_ds = ds;
631         } else if (rbsa.fromguid && !(flags & DRR_FLAG_CLONE)) {
632                 /* online incremental receive */
633
634                 /* tmp clone name is: tofs/%tosnap" */
635                 (void) snprintf(rbsa.clonelastname, sizeof (rbsa.clonelastname),
636                     "%%%s", tosnap);
637
638                 /* open the dataset we are logically receiving into */
639                 err = dsl_dataset_open(tofs,
640                     DS_MODE_STANDARD, dmu_recv_tag, &ds);
641                 if (err)
642                         return (err);
643
644                 rbsa.force = force;
645                 err = dsl_sync_task_do(ds->ds_dir->dd_pool,
646                     recv_incremental_check,
647                     recv_online_incremental_sync, ds, &rbsa, 5);
648                 if (err) {
649                         dsl_dataset_close(ds, DS_MODE_STANDARD, dmu_recv_tag);
650                         return (err);
651                 }
652                 drc->drc_logical_ds = ds;
653                 drc->drc_real_ds = rbsa.ds;
654         } else {
655                 /* create new fs -- full backup or clone */
656                 dsl_dir_t *dd = NULL;
657                 const char *tail;
658
659                 err = dsl_dir_open(tofs, FTAG, &dd, &tail);
660                 if (err)
661                         return (err);
662                 if (tail == NULL) {
663                         if (!force) {
664                                 dsl_dir_close(dd, FTAG);
665                                 return (EEXIST);
666                         }
667
668                         rw_enter(&dd->dd_pool->dp_config_rwlock, RW_READER);
669                         err = dsl_dataset_open_obj(dd->dd_pool,
670                             dd->dd_phys->dd_head_dataset_obj, NULL,
671                             DS_MODE_EXCLUSIVE | DS_MODE_INCONSISTENT,
672                             FTAG, &ds);
673                         rw_exit(&dd->dd_pool->dp_config_rwlock);
674                         if (err) {
675                                 dsl_dir_close(dd, FTAG);
676                                 return (err);
677                         }
678
679                         err = dsl_sync_task_do(dd->dd_pool,
680                             recv_full_existing_check,
681                             recv_full_existing_sync, ds, &rbsa, 5);
682                         /* if successful, sync task closes the ds for us */
683                         if (err)
684                                 dsl_dataset_close(ds, DS_MODE_EXCLUSIVE, FTAG);
685                 } else {
686                         err = dsl_sync_task_do(dd->dd_pool, recv_full_check,
687                             recv_full_sync, dd, &rbsa, 5);
688                         if (err)
689                                 return (err);
690                 }
691                 dsl_dir_close(dd, FTAG);
692                 if (err)
693                         return (err);
694                 drc->drc_logical_ds = drc->drc_real_ds = rbsa.ds;
695                 drc->drc_newfs = B_TRUE;
696         }
697
698         /* downgrade our hold on the ds from EXCLUSIVE to PRIMARY */
699         dsl_dataset_downgrade(drc->drc_real_ds,
700             DS_MODE_EXCLUSIVE, DS_MODE_PRIMARY);
701
702         return (0);
703 }
704
705 struct restorearg {
706         int err;
707         int byteswap;
708         vnode_t *vp;
709         char *buf;
710         uint64_t voff;
711         int bufsize; /* amount of memory allocated for buf */
712         zio_cksum_t cksum;
713 };
714
715 static void *
716 restore_read(struct restorearg *ra, int len)
717 {
718         void *rv;
719         int done = 0;
720
721         /* some things will require 8-byte alignment, so everything must */
722         ASSERT3U(len % 8, ==, 0);
723
724         while (done < len) {
725                 ssize_t resid;
726
727                 ra->err = vn_rdwr(UIO_READ, ra->vp,
728                     (caddr_t)ra->buf + done, len - done,
729                     ra->voff, UIO_SYSSPACE, FAPPEND,
730                     RLIM64_INFINITY, CRED(), &resid);
731
732                 if (resid == len - done)
733                         ra->err = EINVAL;
734                 ra->voff += len - done - resid;
735                 done = len - resid;
736                 if (ra->err)
737                         return (NULL);
738         }
739
740         ASSERT3U(done, ==, len);
741         rv = ra->buf;
742         if (ra->byteswap)
743                 fletcher_4_incremental_byteswap(rv, len, &ra->cksum);
744         else
745                 fletcher_4_incremental_native(rv, len, &ra->cksum);
746         return (rv);
747 }
748
749 static void
750 backup_byteswap(dmu_replay_record_t *drr)
751 {
752 #define DO64(X) (drr->drr_u.X = BSWAP_64(drr->drr_u.X))
753 #define DO32(X) (drr->drr_u.X = BSWAP_32(drr->drr_u.X))
754         drr->drr_type = BSWAP_32(drr->drr_type);
755         drr->drr_payloadlen = BSWAP_32(drr->drr_payloadlen);
756         switch (drr->drr_type) {
757         case DRR_BEGIN:
758                 DO64(drr_begin.drr_magic);
759                 DO64(drr_begin.drr_version);
760                 DO64(drr_begin.drr_creation_time);
761                 DO32(drr_begin.drr_type);
762                 DO32(drr_begin.drr_flags);
763                 DO64(drr_begin.drr_toguid);
764                 DO64(drr_begin.drr_fromguid);
765                 break;
766         case DRR_OBJECT:
767                 DO64(drr_object.drr_object);
768                 /* DO64(drr_object.drr_allocation_txg); */
769                 DO32(drr_object.drr_type);
770                 DO32(drr_object.drr_bonustype);
771                 DO32(drr_object.drr_blksz);
772                 DO32(drr_object.drr_bonuslen);
773                 break;
774         case DRR_FREEOBJECTS:
775                 DO64(drr_freeobjects.drr_firstobj);
776                 DO64(drr_freeobjects.drr_numobjs);
777                 break;
778         case DRR_WRITE:
779                 DO64(drr_write.drr_object);
780                 DO32(drr_write.drr_type);
781                 DO64(drr_write.drr_offset);
782                 DO64(drr_write.drr_length);
783                 break;
784         case DRR_FREE:
785                 DO64(drr_free.drr_object);
786                 DO64(drr_free.drr_offset);
787                 DO64(drr_free.drr_length);
788                 break;
789         case DRR_END:
790                 DO64(drr_end.drr_checksum.zc_word[0]);
791                 DO64(drr_end.drr_checksum.zc_word[1]);
792                 DO64(drr_end.drr_checksum.zc_word[2]);
793                 DO64(drr_end.drr_checksum.zc_word[3]);
794                 break;
795         }
796 #undef DO64
797 #undef DO32
798 }
799
800 static int
801 restore_object(struct restorearg *ra, objset_t *os, struct drr_object *drro)
802 {
803         int err;
804         dmu_tx_t *tx;
805
806         err = dmu_object_info(os, drro->drr_object, NULL);
807
808         if (err != 0 && err != ENOENT)
809                 return (EINVAL);
810
811         if (drro->drr_type == DMU_OT_NONE ||
812             drro->drr_type >= DMU_OT_NUMTYPES ||
813             drro->drr_bonustype >= DMU_OT_NUMTYPES ||
814             drro->drr_checksum >= ZIO_CHECKSUM_FUNCTIONS ||
815             drro->drr_compress >= ZIO_COMPRESS_FUNCTIONS ||
816             P2PHASE(drro->drr_blksz, SPA_MINBLOCKSIZE) ||
817             drro->drr_blksz < SPA_MINBLOCKSIZE ||
818             drro->drr_blksz > SPA_MAXBLOCKSIZE ||
819             drro->drr_bonuslen > DN_MAX_BONUSLEN) {
820                 return (EINVAL);
821         }
822
823         tx = dmu_tx_create(os);
824
825         if (err == ENOENT) {
826                 /* currently free, want to be allocated */
827                 dmu_tx_hold_bonus(tx, DMU_NEW_OBJECT);
828                 dmu_tx_hold_write(tx, DMU_NEW_OBJECT, 0, 1);
829                 err = dmu_tx_assign(tx, TXG_WAIT);
830                 if (err) {
831                         dmu_tx_abort(tx);
832                         return (err);
833                 }
834                 err = dmu_object_claim(os, drro->drr_object,
835                     drro->drr_type, drro->drr_blksz,
836                     drro->drr_bonustype, drro->drr_bonuslen, tx);
837         } else {
838                 /* currently allocated, want to be allocated */
839                 dmu_tx_hold_bonus(tx, drro->drr_object);
840                 /*
841                  * We may change blocksize, so need to
842                  * hold_write
843                  */
844                 dmu_tx_hold_write(tx, drro->drr_object, 0, 1);
845                 err = dmu_tx_assign(tx, TXG_WAIT);
846                 if (err) {
847                         dmu_tx_abort(tx);
848                         return (err);
849                 }
850
851                 err = dmu_object_reclaim(os, drro->drr_object,
852                     drro->drr_type, drro->drr_blksz,
853                     drro->drr_bonustype, drro->drr_bonuslen, tx);
854         }
855         if (err) {
856                 dmu_tx_commit(tx);
857                 return (EINVAL);
858         }
859
860         dmu_object_set_checksum(os, drro->drr_object, drro->drr_checksum, tx);
861         dmu_object_set_compress(os, drro->drr_object, drro->drr_compress, tx);
862
863         if (drro->drr_bonuslen) {
864                 dmu_buf_t *db;
865                 void *data;
866                 VERIFY(0 == dmu_bonus_hold(os, drro->drr_object, FTAG, &db));
867                 dmu_buf_will_dirty(db, tx);
868
869                 ASSERT3U(db->db_size, >=, drro->drr_bonuslen);
870                 data = restore_read(ra, P2ROUNDUP(drro->drr_bonuslen, 8));
871                 if (data == NULL) {
872                         dmu_tx_commit(tx);
873                         return (ra->err);
874                 }
875                 bcopy(data, db->db_data, drro->drr_bonuslen);
876                 if (ra->byteswap) {
877                         dmu_ot[drro->drr_bonustype].ot_byteswap(db->db_data,
878                             drro->drr_bonuslen);
879                 }
880                 dmu_buf_rele(db, FTAG);
881         }
882         dmu_tx_commit(tx);
883         return (0);
884 }
885
886 /* ARGSUSED */
887 static int
888 restore_freeobjects(struct restorearg *ra, objset_t *os,
889     struct drr_freeobjects *drrfo)
890 {
891         uint64_t obj;
892
893         if (drrfo->drr_firstobj + drrfo->drr_numobjs < drrfo->drr_firstobj)
894                 return (EINVAL);
895
896         for (obj = drrfo->drr_firstobj;
897             obj < drrfo->drr_firstobj + drrfo->drr_numobjs;
898             (void) dmu_object_next(os, &obj, FALSE, 0)) {
899                 dmu_tx_t *tx;
900                 int err;
901
902                 if (dmu_object_info(os, obj, NULL) != 0)
903                         continue;
904
905                 tx = dmu_tx_create(os);
906                 dmu_tx_hold_bonus(tx, obj);
907                 err = dmu_tx_assign(tx, TXG_WAIT);
908                 if (err) {
909                         dmu_tx_abort(tx);
910                         return (err);
911                 }
912                 err = dmu_object_free(os, obj, tx);
913                 dmu_tx_commit(tx);
914                 if (err && err != ENOENT)
915                         return (EINVAL);
916         }
917         return (0);
918 }
919
920 static int
921 restore_write(struct restorearg *ra, objset_t *os,
922     struct drr_write *drrw)
923 {
924         dmu_tx_t *tx;
925         void *data;
926         int err;
927
928         if (drrw->drr_offset + drrw->drr_length < drrw->drr_offset ||
929             drrw->drr_type >= DMU_OT_NUMTYPES)
930                 return (EINVAL);
931
932         data = restore_read(ra, drrw->drr_length);
933         if (data == NULL)
934                 return (ra->err);
935
936         if (dmu_object_info(os, drrw->drr_object, NULL) != 0)
937                 return (EINVAL);
938
939         tx = dmu_tx_create(os);
940
941         dmu_tx_hold_write(tx, drrw->drr_object,
942             drrw->drr_offset, drrw->drr_length);
943         err = dmu_tx_assign(tx, TXG_WAIT);
944         if (err) {
945                 dmu_tx_abort(tx);
946                 return (err);
947         }
948         if (ra->byteswap)
949                 dmu_ot[drrw->drr_type].ot_byteswap(data, drrw->drr_length);
950         dmu_write(os, drrw->drr_object,
951             drrw->drr_offset, drrw->drr_length, data, tx);
952         dmu_tx_commit(tx);
953         return (0);
954 }
955
956 /* ARGSUSED */
957 static int
958 restore_free(struct restorearg *ra, objset_t *os,
959     struct drr_free *drrf)
960 {
961         dmu_tx_t *tx;
962         int err;
963
964         if (drrf->drr_length != -1ULL &&
965             drrf->drr_offset + drrf->drr_length < drrf->drr_offset)
966                 return (EINVAL);
967
968         if (dmu_object_info(os, drrf->drr_object, NULL) != 0)
969                 return (EINVAL);
970
971         tx = dmu_tx_create(os);
972
973         dmu_tx_hold_free(tx, drrf->drr_object,
974             drrf->drr_offset, drrf->drr_length);
975         err = dmu_tx_assign(tx, TXG_WAIT);
976         if (err) {
977                 dmu_tx_abort(tx);
978                 return (err);
979         }
980         err = dmu_free_range(os, drrf->drr_object,
981             drrf->drr_offset, drrf->drr_length, tx);
982         dmu_tx_commit(tx);
983         return (err);
984 }
985
986 void
987 dmu_recv_abort_cleanup(dmu_recv_cookie_t *drc)
988 {
989         if (drc->drc_newfs || drc->drc_real_ds != drc->drc_logical_ds) {
990                 /*
991                  * online incremental or new fs: destroy the fs (which
992                  * may be a clone) that we created
993                  */
994                 (void) dsl_dataset_destroy(drc->drc_real_ds, dmu_recv_tag);
995                 if (drc->drc_real_ds != drc->drc_logical_ds) {
996                         dsl_dataset_close(drc->drc_logical_ds,
997                             DS_MODE_STANDARD, dmu_recv_tag);
998                 }
999         } else {
1000                 /*
1001                  * offline incremental: rollback to most recent snapshot.
1002                  */
1003                 int lmode = DS_MODE_PRIMARY;
1004                 if (dsl_dataset_tryupgrade(drc->drc_real_ds,
1005                     DS_MODE_PRIMARY, DS_MODE_EXCLUSIVE)) {
1006                         lmode = DS_MODE_EXCLUSIVE;
1007                         (void) dsl_dataset_rollback(drc->drc_real_ds,
1008                             DMU_OST_NONE);
1009                 }
1010                 dsl_dataset_close(drc->drc_real_ds, lmode, FTAG);
1011         }
1012 }
1013
1014 /*
1015  * NB: callers *must* call dmu_recv_end() if this succeeds.
1016  */
1017 int
1018 dmu_recv_stream(dmu_recv_cookie_t *drc, vnode_t *vp, offset_t *voffp)
1019 {
1020         struct restorearg ra = { 0 };
1021         dmu_replay_record_t *drr;
1022         objset_t *os;
1023         zio_cksum_t pcksum;
1024
1025         if (drc->drc_drrb->drr_magic == BSWAP_64(DMU_BACKUP_MAGIC))
1026                 ra.byteswap = TRUE;
1027
1028         {
1029                 /* compute checksum of drr_begin record */
1030                 dmu_replay_record_t *drr;
1031                 drr = kmem_zalloc(sizeof (dmu_replay_record_t), KM_SLEEP);
1032
1033                 drr->drr_type = DRR_BEGIN;
1034                 drr->drr_u.drr_begin = *drc->drc_drrb;
1035                 if (ra.byteswap) {
1036                         fletcher_4_incremental_byteswap(drr,
1037                             sizeof (dmu_replay_record_t), &ra.cksum);
1038                 } else {
1039                         fletcher_4_incremental_native(drr,
1040                             sizeof (dmu_replay_record_t), &ra.cksum);
1041                 }
1042                 kmem_free(drr, sizeof (dmu_replay_record_t));
1043         }
1044
1045         if (ra.byteswap) {
1046                 struct drr_begin *drrb = drc->drc_drrb;
1047                 drrb->drr_magic = BSWAP_64(drrb->drr_magic);
1048                 drrb->drr_version = BSWAP_64(drrb->drr_version);
1049                 drrb->drr_creation_time = BSWAP_64(drrb->drr_creation_time);
1050                 drrb->drr_type = BSWAP_32(drrb->drr_type);
1051                 drrb->drr_toguid = BSWAP_64(drrb->drr_toguid);
1052                 drrb->drr_fromguid = BSWAP_64(drrb->drr_fromguid);
1053         }
1054
1055         ra.vp = vp;
1056         ra.voff = *voffp;
1057         ra.bufsize = 1<<20;
1058         ra.buf = kmem_alloc(ra.bufsize, KM_SLEEP);
1059
1060         /* these were verified in dmu_recv_begin */
1061         ASSERT(drc->drc_drrb->drr_version == DMU_BACKUP_STREAM_VERSION);
1062         ASSERT(drc->drc_drrb->drr_type < DMU_OST_NUMTYPES);
1063
1064         /*
1065          * Open the objset we are modifying.
1066          */
1067         VERIFY(dmu_objset_open_ds(drc->drc_real_ds, DMU_OST_ANY, &os) == 0);
1068
1069         ASSERT(drc->drc_real_ds->ds_phys->ds_flags & DS_FLAG_INCONSISTENT);
1070
1071         /*
1072          * Read records and process them.
1073          */
1074         pcksum = ra.cksum;
1075         while (ra.err == 0 &&
1076             NULL != (drr = restore_read(&ra, sizeof (*drr)))) {
1077                 if (issig(JUSTLOOKING) && issig(FORREAL)) {
1078                         ra.err = EINTR;
1079                         goto out;
1080                 }
1081
1082                 if (ra.byteswap)
1083                         backup_byteswap(drr);
1084
1085                 switch (drr->drr_type) {
1086                 case DRR_OBJECT:
1087                 {
1088                         /*
1089                          * We need to make a copy of the record header,
1090                          * because restore_{object,write} may need to
1091                          * restore_read(), which will invalidate drr.
1092                          */
1093                         struct drr_object drro = drr->drr_u.drr_object;
1094                         ra.err = restore_object(&ra, os, &drro);
1095                         break;
1096                 }
1097                 case DRR_FREEOBJECTS:
1098                 {
1099                         struct drr_freeobjects drrfo =
1100                             drr->drr_u.drr_freeobjects;
1101                         ra.err = restore_freeobjects(&ra, os, &drrfo);
1102                         break;
1103                 }
1104                 case DRR_WRITE:
1105                 {
1106                         struct drr_write drrw = drr->drr_u.drr_write;
1107                         ra.err = restore_write(&ra, os, &drrw);
1108                         break;
1109                 }
1110                 case DRR_FREE:
1111                 {
1112                         struct drr_free drrf = drr->drr_u.drr_free;
1113                         ra.err = restore_free(&ra, os, &drrf);
1114                         break;
1115                 }
1116                 case DRR_END:
1117                 {
1118                         struct drr_end drre = drr->drr_u.drr_end;
1119                         /*
1120                          * We compare against the *previous* checksum
1121                          * value, because the stored checksum is of
1122                          * everything before the DRR_END record.
1123                          */
1124                         if (!ZIO_CHECKSUM_EQUAL(drre.drr_checksum, pcksum))
1125                                 ra.err = ECKSUM;
1126                         goto out;
1127                 }
1128                 default:
1129                         ra.err = EINVAL;
1130                         goto out;
1131                 }
1132                 pcksum = ra.cksum;
1133         }
1134         ASSERT(ra.err != 0);
1135
1136 out:
1137         dmu_objset_close(os);
1138
1139         if (ra.err != 0) {
1140                 /*
1141                  * rollback or destroy what we created, so we don't
1142                  * leave it in the restoring state.
1143                  */
1144                 txg_wait_synced(drc->drc_real_ds->ds_dir->dd_pool, 0);
1145                 dmu_recv_abort_cleanup(drc);
1146         }
1147
1148         kmem_free(ra.buf, ra.bufsize);
1149         *voffp = ra.voff;
1150         return (ra.err);
1151 }
1152
1153 struct recvendsyncarg {
1154         char *tosnap;
1155         uint64_t creation_time;
1156         uint64_t toguid;
1157 };
1158
1159 static int
1160 recv_end_check(void *arg1, void *arg2, dmu_tx_t *tx)
1161 {
1162         dsl_dataset_t *ds = arg1;
1163         struct recvendsyncarg *resa = arg2;
1164
1165         return (dsl_dataset_snapshot_check(ds, resa->tosnap, tx));
1166 }
1167
1168 static void
1169 recv_end_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx)
1170 {
1171         dsl_dataset_t *ds = arg1;
1172         struct recvendsyncarg *resa = arg2;
1173
1174         dsl_dataset_snapshot_sync(ds, resa->tosnap, cr, tx);
1175
1176         /* set snapshot's creation time and guid */
1177         dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx);
1178         ds->ds_prev->ds_phys->ds_creation_time = resa->creation_time;
1179         ds->ds_prev->ds_phys->ds_guid = resa->toguid;
1180         ds->ds_prev->ds_phys->ds_flags &= ~DS_FLAG_INCONSISTENT;
1181
1182         dmu_buf_will_dirty(ds->ds_dbuf, tx);
1183         ds->ds_phys->ds_flags &= ~DS_FLAG_INCONSISTENT;
1184 }
1185
1186 int
1187 dmu_recv_end(dmu_recv_cookie_t *drc)
1188 {
1189         int err = 0;
1190         int lmode;
1191
1192         /*
1193          * XXX hack; seems the ds is still dirty and
1194          * dsl_pool_zil_clean() expects it to have a ds_user_ptr (and
1195          * zil), but clone_swap() can close it.
1196          */
1197         txg_wait_synced(drc->drc_real_ds->ds_dir->dd_pool, 0);
1198
1199         if (dsl_dataset_tryupgrade(drc->drc_real_ds,
1200             DS_MODE_PRIMARY, DS_MODE_EXCLUSIVE)) {
1201                 lmode = DS_MODE_EXCLUSIVE;
1202         } else {
1203                 dmu_recv_abort_cleanup(drc);
1204                 return (EBUSY);
1205         }
1206
1207         if (drc->drc_logical_ds != drc->drc_real_ds) {
1208                 if (err == 0 && dsl_dataset_tryupgrade(drc->drc_logical_ds,
1209                     DS_MODE_STANDARD, DS_MODE_EXCLUSIVE)) {
1210                         lmode = DS_MODE_EXCLUSIVE;
1211                         err = dsl_dataset_clone_swap(drc->drc_real_ds,
1212                             drc->drc_logical_ds, drc->drc_force);
1213                 } else {
1214                         lmode = DS_MODE_STANDARD;
1215                         err = EBUSY;
1216                 }
1217         }
1218
1219         if (err == 0) {
1220                 struct recvendsyncarg resa;
1221
1222                 resa.creation_time = drc->drc_drrb->drr_creation_time;
1223                 resa.toguid = drc->drc_drrb->drr_toguid;
1224                 resa.tosnap = drc->drc_tosnap;
1225
1226                 err = dsl_sync_task_do(drc->drc_real_ds->ds_dir->dd_pool,
1227                     recv_end_check, recv_end_sync,
1228                     drc->drc_logical_ds, &resa, 3);
1229                 if (err) {
1230                         if (drc->drc_newfs) {
1231                                 ASSERT(drc->drc_logical_ds == drc->drc_real_ds);
1232                                 (void) dsl_dataset_destroy(drc->drc_real_ds,
1233                                     dmu_recv_tag);
1234                                 return (err);
1235                         } else {
1236                                 (void) dsl_dataset_rollback(drc->drc_logical_ds,
1237                                     DMU_OST_NONE);
1238                         }
1239                 }
1240         }
1241
1242         if (drc->drc_logical_ds != drc->drc_real_ds) {
1243                 /* dsl_dataset_destroy() will close the ds */
1244                 (void) dsl_dataset_destroy(drc->drc_real_ds, dmu_recv_tag);
1245         }
1246         /* close the hold from dmu_recv_begin */
1247         dsl_dataset_close(drc->drc_logical_ds, lmode, dmu_recv_tag);
1248         return (err);
1249 }