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 2011 Nexenta Systems, Inc. All rights reserved.
24 * Copyright (c) 2011, 2015 by Delphix. All rights reserved.
25 * Copyright (c) 2014, Joyent, Inc. All rights reserved.
26 * Copyright 2014 HybridCluster. All rights reserved.
27 * Copyright 2016 RackTop Systems.
28 * Copyright (c) 2014 Integros [integros.com]
29 */
30
31#include <sys/dmu.h>
32#include <sys/dmu_impl.h>
33#include <sys/dmu_tx.h>
34#include <sys/dbuf.h>
35#include <sys/dnode.h>
36#include <sys/zfs_context.h>
37#include <sys/dmu_objset.h>
38#include <sys/dmu_traverse.h>
39#include <sys/dsl_dataset.h>
40#include <sys/dsl_dir.h>
41#include <sys/dsl_prop.h>
42#include <sys/dsl_pool.h>
43#include <sys/dsl_synctask.h>
44#include <sys/zfs_ioctl.h>
45#include <sys/zap.h>
46#include <sys/zio_checksum.h>
47#include <sys/zfs_znode.h>
48#include <zfs_fletcher.h>
49#include <sys/avl.h>
50#include <sys/ddt.h>
51#include <sys/zfs_onexit.h>
52#include <sys/dmu_recv.h>
53#include <sys/dsl_destroy.h>
54#include <sys/blkptr.h>
55#include <sys/dsl_bookmark.h>
56#include <sys/zfeature.h>
57#include <sys/bqueue.h>
58
59int zfs_recv_queue_length = SPA_MAXBLOCKSIZE;
60
61static char *dmu_recv_tag = "dmu_recv_tag";
62const char *recv_clone_name = "%recv";
63
64static void byteswap_record(dmu_replay_record_t *drr);
65
66typedef struct dmu_recv_begin_arg {
67	const char *drba_origin;
68	dmu_recv_cookie_t *drba_cookie;
69	cred_t *drba_cred;
70	dsl_crypto_params_t *drba_dcp;
71} dmu_recv_begin_arg_t;
72
73static int
74recv_begin_check_existing_impl(dmu_recv_begin_arg_t *drba, dsl_dataset_t *ds,
75    uint64_t fromguid, uint64_t featureflags)
76{
77	uint64_t val;
78	int error;
79	dsl_pool_t *dp = ds->ds_dir->dd_pool;
80	boolean_t encrypted = ds->ds_dir->dd_crypto_obj != 0;
81	boolean_t raw = (featureflags & DMU_BACKUP_FEATURE_RAW) != 0;
82	boolean_t embed = (featureflags & DMU_BACKUP_FEATURE_EMBED_DATA) != 0;
83
84	/* temporary clone name must not exist */
85	error = zap_lookup(dp->dp_meta_objset,
86	    dsl_dir_phys(ds->ds_dir)->dd_child_dir_zapobj, recv_clone_name,
87	    8, 1, &val);
88	if (error != ENOENT)
89		return (error == 0 ? EBUSY : error);
90
91	/* new snapshot name must not exist */
92	error = zap_lookup(dp->dp_meta_objset,
93	    dsl_dataset_phys(ds)->ds_snapnames_zapobj,
94	    drba->drba_cookie->drc_tosnap, 8, 1, &val);
95	if (error != ENOENT)
96		return (error == 0 ? EEXIST : error);
97
98	/*
99	 * Check snapshot limit before receiving. We'll recheck again at the
100	 * end, but might as well abort before receiving if we're already over
101	 * the limit.
102	 *
103	 * Note that we do not check the file system limit with
104	 * dsl_dir_fscount_check because the temporary %clones don't count
105	 * against that limit.
106	 */
107	error = dsl_fs_ss_limit_check(ds->ds_dir, 1, ZFS_PROP_SNAPSHOT_LIMIT,
108	    NULL, drba->drba_cred);
109	if (error != 0)
110		return (error);
111
112	if (fromguid != 0) {
113		dsl_dataset_t *snap;
114		uint64_t obj = dsl_dataset_phys(ds)->ds_prev_snap_obj;
115
116		/* Can't raw receive on top of an unencrypted dataset */
117		if (!encrypted && raw)
118			return (SET_ERROR(EINVAL));
119
120		/* Encryption is incompatible with embedded data */
121		if (encrypted && embed)
122			return (SET_ERROR(EINVAL));
123
124		/* Find snapshot in this dir that matches fromguid. */
125		while (obj != 0) {
126			error = dsl_dataset_hold_obj(dp, obj, FTAG,
127			    &snap);
128			if (error != 0)
129				return (SET_ERROR(ENODEV));
130			if (snap->ds_dir != ds->ds_dir) {
131				dsl_dataset_rele(snap, FTAG);
132				return (SET_ERROR(ENODEV));
133			}
134			if (dsl_dataset_phys(snap)->ds_guid == fromguid)
135				break;
136			obj = dsl_dataset_phys(snap)->ds_prev_snap_obj;
137			dsl_dataset_rele(snap, FTAG);
138		}
139		if (obj == 0)
140			return (SET_ERROR(ENODEV));
141
142		if (drba->drba_cookie->drc_force) {
143			drba->drba_cookie->drc_fromsnapobj = obj;
144		} else {
145			/*
146			 * If we are not forcing, there must be no
147			 * changes since fromsnap.
148			 */
149			if (dsl_dataset_modified_since_snap(ds, snap)) {
150				dsl_dataset_rele(snap, FTAG);
151				return (SET_ERROR(ETXTBSY));
152			}
153			drba->drba_cookie->drc_fromsnapobj =
154			    ds->ds_prev->ds_object;
155		}
156
157		dsl_dataset_rele(snap, FTAG);
158	} else {
159		/* if full, then must be forced */
160		if (!drba->drba_cookie->drc_force)
161			return (SET_ERROR(EEXIST));
162
163		/*
164		 * We don't support using zfs recv -F to blow away
165		 * encrypted filesystems. This would require the
166		 * dsl dir to point to the old encryption key and
167		 * the new one at the same time during the receive.
168		 */
169		if ((!encrypted && raw) || encrypted)
170			return (SET_ERROR(EINVAL));
171
172		/*
173		 * Perform the same encryption checks we would if
174		 * we were creating a new dataset from scratch.
175		 */
176		if (!raw) {
177			boolean_t will_encrypt;
178
179			error = dmu_objset_create_crypt_check(
180			    ds->ds_dir->dd_parent, drba->drba_dcp,
181			    &will_encrypt);
182			if (error != 0)
183				return (error);
184
185			if (will_encrypt && embed)
186				return (SET_ERROR(EINVAL));
187		}
188
189		drba->drba_cookie->drc_fromsnapobj = 0;
190	}
191
192	return (0);
193
194}
195
196static int
197dmu_recv_begin_check(void *arg, dmu_tx_t *tx)
198{
199	dmu_recv_begin_arg_t *drba = arg;
200	dsl_pool_t *dp = dmu_tx_pool(tx);
201	struct drr_begin *drrb = drba->drba_cookie->drc_drrb;
202	uint64_t fromguid = drrb->drr_fromguid;
203	int flags = drrb->drr_flags;
204	ds_hold_flags_t dsflags = 0;
205	int error;
206	uint64_t featureflags = DMU_GET_FEATUREFLAGS(drrb->drr_versioninfo);
207	dsl_dataset_t *ds;
208	const char *tofs = drba->drba_cookie->drc_tofs;
209
210	/* already checked */
211	ASSERT3U(drrb->drr_magic, ==, DMU_BACKUP_MAGIC);
212	ASSERT(!(featureflags & DMU_BACKUP_FEATURE_RESUMING));
213
214	if (DMU_GET_STREAM_HDRTYPE(drrb->drr_versioninfo) ==
215	    DMU_COMPOUNDSTREAM ||
216	    drrb->drr_type >= DMU_OST_NUMTYPES ||
217	    ((flags & DRR_FLAG_CLONE) && drba->drba_origin == NULL))
218		return (SET_ERROR(EINVAL));
219
220	/* Verify pool version supports SA if SA_SPILL feature set */
221	if ((featureflags & DMU_BACKUP_FEATURE_SA_SPILL) &&
222	    spa_version(dp->dp_spa) < SPA_VERSION_SA)
223		return (SET_ERROR(ENOTSUP));
224
225	if (drba->drba_cookie->drc_resumable &&
226	    !spa_feature_is_enabled(dp->dp_spa, SPA_FEATURE_EXTENSIBLE_DATASET))
227		return (SET_ERROR(ENOTSUP));
228
229	/*
230	 * The receiving code doesn't know how to translate a WRITE_EMBEDDED
231	 * record to a plain WRITE record, so the pool must have the
232	 * EMBEDDED_DATA feature enabled if the stream has WRITE_EMBEDDED
233	 * records.  Same with WRITE_EMBEDDED records that use LZ4 compression.
234	 */
235	if ((featureflags & DMU_BACKUP_FEATURE_EMBED_DATA) &&
236	    !spa_feature_is_enabled(dp->dp_spa, SPA_FEATURE_EMBEDDED_DATA))
237		return (SET_ERROR(ENOTSUP));
238	if ((featureflags & DMU_BACKUP_FEATURE_LZ4) &&
239	    !spa_feature_is_enabled(dp->dp_spa, SPA_FEATURE_LZ4_COMPRESS))
240		return (SET_ERROR(ENOTSUP));
241
242	/*
243	 * The receiving code doesn't know how to translate large blocks
244	 * to smaller ones, so the pool must have the LARGE_BLOCKS
245	 * feature enabled if the stream has LARGE_BLOCKS. Same with
246	 * large dnodes.
247	 */
248	if ((featureflags & DMU_BACKUP_FEATURE_LARGE_BLOCKS) &&
249	    !spa_feature_is_enabled(dp->dp_spa, SPA_FEATURE_LARGE_BLOCKS))
250		return (SET_ERROR(ENOTSUP));
251	if ((featureflags & DMU_BACKUP_FEATURE_LARGE_DNODE) &&
252	    !spa_feature_is_enabled(dp->dp_spa, SPA_FEATURE_LARGE_DNODE))
253		return (SET_ERROR(ENOTSUP));
254
255	if (featureflags & DMU_BACKUP_FEATURE_RAW) {
256		/* raw receives require the encryption feature */
257		if (!spa_feature_is_enabled(dp->dp_spa, SPA_FEATURE_ENCRYPTION))
258			return (SET_ERROR(ENOTSUP));
259
260		/* embedded data is incompatible with encryption and raw recv */
261		if (featureflags & DMU_BACKUP_FEATURE_EMBED_DATA)
262			return (SET_ERROR(EINVAL));
263
264		/* raw receives require spill block allocation flag */
265		if (!(flags & DRR_FLAG_SPILL_BLOCK))
266			return (SET_ERROR(ZFS_ERR_SPILL_BLOCK_FLAG_MISSING));
267	} else {
268		dsflags |= DS_HOLD_FLAG_DECRYPT;
269	}
270
271	error = dsl_dataset_hold_flags(dp, tofs, dsflags, FTAG, &ds);
272	if (error == 0) {
273		/* target fs already exists; recv into temp clone */
274
275		/* Can't recv a clone into an existing fs */
276		if (flags & DRR_FLAG_CLONE || drba->drba_origin) {
277			dsl_dataset_rele_flags(ds, dsflags, FTAG);
278			return (SET_ERROR(EINVAL));
279		}
280
281		error = recv_begin_check_existing_impl(drba, ds, fromguid,
282		    featureflags);
283		dsl_dataset_rele_flags(ds, dsflags, FTAG);
284	} else if (error == ENOENT) {
285		/* target fs does not exist; must be a full backup or clone */
286		char buf[ZFS_MAX_DATASET_NAME_LEN];
287
288		/*
289		 * If it's a non-clone incremental, we are missing the
290		 * target fs, so fail the recv.
291		 */
292		if (fromguid != 0 && !(flags & DRR_FLAG_CLONE ||
293		    drba->drba_origin))
294			return (SET_ERROR(ENOENT));
295
296		/*
297		 * If we're receiving a full send as a clone, and it doesn't
298		 * contain all the necessary free records and freeobject
299		 * records, reject it.
300		 */
301		if (fromguid == 0 && drba->drba_origin &&
302		    !(flags & DRR_FLAG_FREERECORDS))
303			return (SET_ERROR(EINVAL));
304
305		/* Open the parent of tofs */
306		ASSERT3U(strlen(tofs), <, sizeof (buf));
307		(void) strlcpy(buf, tofs, strrchr(tofs, '/') - tofs + 1);
308		error = dsl_dataset_hold(dp, buf, FTAG, &ds);
309		if (error != 0)
310			return (error);
311
312		if ((featureflags & DMU_BACKUP_FEATURE_RAW) == 0 &&
313		    drba->drba_origin == NULL) {
314			boolean_t will_encrypt;
315
316			/*
317			 * Check that we aren't breaking any encryption rules
318			 * and that we have all the parameters we need to
319			 * create an encrypted dataset if necessary. If we are
320			 * making an encrypted dataset the stream can't have
321			 * embedded data.
322			 */
323			error = dmu_objset_create_crypt_check(ds->ds_dir,
324			    drba->drba_dcp, &will_encrypt);
325			if (error != 0) {
326				dsl_dataset_rele(ds, FTAG);
327				return (error);
328			}
329
330			if (will_encrypt &&
331			    (featureflags & DMU_BACKUP_FEATURE_EMBED_DATA)) {
332				dsl_dataset_rele(ds, FTAG);
333				return (SET_ERROR(EINVAL));
334			}
335		}
336
337		/*
338		 * Check filesystem and snapshot limits before receiving. We'll
339		 * recheck snapshot limits again at the end (we create the
340		 * filesystems and increment those counts during begin_sync).
341		 */
342		error = dsl_fs_ss_limit_check(ds->ds_dir, 1,
343		    ZFS_PROP_FILESYSTEM_LIMIT, NULL, drba->drba_cred);
344		if (error != 0) {
345			dsl_dataset_rele(ds, FTAG);
346			return (error);
347		}
348
349		error = dsl_fs_ss_limit_check(ds->ds_dir, 1,
350		    ZFS_PROP_SNAPSHOT_LIMIT, NULL, drba->drba_cred);
351		if (error != 0) {
352			dsl_dataset_rele(ds, FTAG);
353			return (error);
354		}
355
356		if (drba->drba_origin != NULL) {
357			dsl_dataset_t *origin;
358
359			error = dsl_dataset_hold(dp, drba->drba_origin,
360			    FTAG, &origin);
361			if (error != 0) {
362				dsl_dataset_rele(ds, FTAG);
363				return (error);
364			}
365			if (!origin->ds_is_snapshot) {
366				dsl_dataset_rele(origin, FTAG);
367				dsl_dataset_rele(ds, FTAG);
368				return (SET_ERROR(EINVAL));
369			}
370			if (dsl_dataset_phys(origin)->ds_guid != fromguid &&
371			    fromguid != 0) {
372				dsl_dataset_rele(origin, FTAG);
373				dsl_dataset_rele(ds, FTAG);
374				return (SET_ERROR(ENODEV));
375			}
376			if (origin->ds_dir->dd_crypto_obj != 0 &&
377			    (featureflags & DMU_BACKUP_FEATURE_EMBED_DATA)) {
378				dsl_dataset_rele(origin, FTAG);
379				dsl_dataset_rele(ds, FTAG);
380				return (SET_ERROR(EINVAL));
381			}
382			dsl_dataset_rele(origin, FTAG);
383		}
384		dsl_dataset_rele(ds, FTAG);
385		error = 0;
386	}
387	return (error);
388}
389
390static void
391dmu_recv_begin_sync(void *arg, dmu_tx_t *tx)
392{
393	dmu_recv_begin_arg_t *drba = arg;
394	dsl_pool_t *dp = dmu_tx_pool(tx);
395	objset_t *mos = dp->dp_meta_objset;
396	struct drr_begin *drrb = drba->drba_cookie->drc_drrb;
397	const char *tofs = drba->drba_cookie->drc_tofs;
398	uint64_t featureflags = DMU_GET_FEATUREFLAGS(drrb->drr_versioninfo);
399	dsl_dataset_t *ds, *newds;
400	objset_t *os;
401	uint64_t dsobj;
402	ds_hold_flags_t dsflags = 0;
403	int error;
404	uint64_t crflags = 0;
405	dsl_crypto_params_t dummy_dcp = { 0 };
406	dsl_crypto_params_t *dcp = drba->drba_dcp;
407
408	if (drrb->drr_flags & DRR_FLAG_CI_DATA)
409		crflags |= DS_FLAG_CI_DATASET;
410
411	if ((featureflags & DMU_BACKUP_FEATURE_RAW) == 0)
412		dsflags |= DS_HOLD_FLAG_DECRYPT;
413
414	/*
415	 * Raw, non-incremental recvs always use a dummy dcp with
416	 * the raw cmd set. Raw incremental recvs do not use a dcp
417	 * since the encryption parameters are already set in stone.
418	 */
419	if (dcp == NULL && drba->drba_cookie->drc_fromsnapobj == 0 &&
420	    drba->drba_origin == NULL) {
421		ASSERT3P(dcp, ==, NULL);
422		dcp = &dummy_dcp;
423
424		if (featureflags & DMU_BACKUP_FEATURE_RAW)
425			dcp->cp_cmd = DCP_CMD_RAW_RECV;
426	}
427
428	error = dsl_dataset_hold_flags(dp, tofs, dsflags, FTAG, &ds);
429	if (error == 0) {
430		/* create temporary clone */
431		dsl_dataset_t *snap = NULL;
432
433		if (drba->drba_cookie->drc_fromsnapobj != 0) {
434			VERIFY0(dsl_dataset_hold_obj(dp,
435			    drba->drba_cookie->drc_fromsnapobj, FTAG, &snap));
436			ASSERT3P(dcp, ==, NULL);
437		}
438
439		dsobj = dsl_dataset_create_sync(ds->ds_dir, recv_clone_name,
440		    snap, crflags, drba->drba_cred, dcp, tx);
441		if (drba->drba_cookie->drc_fromsnapobj != 0)
442			dsl_dataset_rele(snap, FTAG);
443		dsl_dataset_rele_flags(ds, dsflags, FTAG);
444	} else {
445		dsl_dir_t *dd;
446		const char *tail;
447		dsl_dataset_t *origin = NULL;
448
449		VERIFY0(dsl_dir_hold(dp, tofs, FTAG, &dd, &tail));
450
451		if (drba->drba_origin != NULL) {
452			VERIFY0(dsl_dataset_hold(dp, drba->drba_origin,
453			    FTAG, &origin));
454			ASSERT3P(dcp, ==, NULL);
455		}
456
457		/* Create new dataset. */
458		dsobj = dsl_dataset_create_sync(dd, strrchr(tofs, '/') + 1,
459		    origin, crflags, drba->drba_cred, dcp, tx);
460		if (origin != NULL)
461			dsl_dataset_rele(origin, FTAG);
462		dsl_dir_rele(dd, FTAG);
463		drba->drba_cookie->drc_newfs = B_TRUE;
464	}
465
466	VERIFY0(dsl_dataset_own_obj(dp, dsobj, dsflags, dmu_recv_tag, &newds));
467	VERIFY0(dmu_objset_from_ds(newds, &os));
468
469	if (drba->drba_cookie->drc_resumable) {
470		dsl_dataset_zapify(newds, tx);
471		if (drrb->drr_fromguid != 0) {
472			VERIFY0(zap_add(mos, dsobj, DS_FIELD_RESUME_FROMGUID,
473			    8, 1, &drrb->drr_fromguid, tx));
474		}
475		VERIFY0(zap_add(mos, dsobj, DS_FIELD_RESUME_TOGUID,
476		    8, 1, &drrb->drr_toguid, tx));
477		VERIFY0(zap_add(mos, dsobj, DS_FIELD_RESUME_TONAME,
478		    1, strlen(drrb->drr_toname) + 1, drrb->drr_toname, tx));
479		uint64_t one = 1;
480		uint64_t zero = 0;
481		VERIFY0(zap_add(mos, dsobj, DS_FIELD_RESUME_OBJECT,
482		    8, 1, &one, tx));
483		VERIFY0(zap_add(mos, dsobj, DS_FIELD_RESUME_OFFSET,
484		    8, 1, &zero, tx));
485		VERIFY0(zap_add(mos, dsobj, DS_FIELD_RESUME_BYTES,
486		    8, 1, &zero, tx));
487		if (featureflags & DMU_BACKUP_FEATURE_LARGE_BLOCKS) {
488			VERIFY0(zap_add(mos, dsobj, DS_FIELD_RESUME_LARGEBLOCK,
489			    8, 1, &one, tx));
490		}
491		if (featureflags & DMU_BACKUP_FEATURE_EMBED_DATA) {
492			VERIFY0(zap_add(mos, dsobj, DS_FIELD_RESUME_EMBEDOK,
493			    8, 1, &one, tx));
494		}
495		if (featureflags & DMU_BACKUP_FEATURE_COMPRESSED) {
496			VERIFY0(zap_add(mos, dsobj, DS_FIELD_RESUME_COMPRESSOK,
497			    8, 1, &one, tx));
498		}
499		if (featureflags & DMU_BACKUP_FEATURE_RAW) {
500			VERIFY0(zap_add(mos, dsobj, DS_FIELD_RESUME_RAWOK,
501			    8, 1, &one, tx));
502		}
503	}
504
505	/*
506	 * Usually the os->os_encrypted value is tied to the presence of a
507	 * DSL Crypto Key object in the dd. However, that will not be received
508	 * until dmu_recv_stream(), so we set the value manually for now.
509	 */
510	if (featureflags & DMU_BACKUP_FEATURE_RAW) {
511		os->os_encrypted = B_TRUE;
512		drba->drba_cookie->drc_raw = B_TRUE;
513	}
514
515	dmu_buf_will_dirty(newds->ds_dbuf, tx);
516	dsl_dataset_phys(newds)->ds_flags |= DS_FLAG_INCONSISTENT;
517
518	/*
519	 * If we actually created a non-clone, we need to create the objset
520	 * in our new dataset. If this is a raw send we postpone this until
521	 * dmu_recv_stream() so that we can allocate the metadnode with the
522	 * properties from the DRR_BEGIN payload.
523	 */
524	rrw_enter(&newds->ds_bp_rwlock, RW_READER, FTAG);
525	if (BP_IS_HOLE(dsl_dataset_get_blkptr(newds)) &&
526	    (featureflags & DMU_BACKUP_FEATURE_RAW) == 0) {
527		(void) dmu_objset_create_impl(dp->dp_spa,
528		    newds, dsl_dataset_get_blkptr(newds), drrb->drr_type, tx);
529	}
530	rrw_exit(&newds->ds_bp_rwlock, FTAG);
531
532	drba->drba_cookie->drc_ds = newds;
533
534	spa_history_log_internal_ds(newds, "receive", tx, "");
535}
536
537static int
538dmu_recv_resume_begin_check(void *arg, dmu_tx_t *tx)
539{
540	dmu_recv_begin_arg_t *drba = arg;
541	dsl_pool_t *dp = dmu_tx_pool(tx);
542	struct drr_begin *drrb = drba->drba_cookie->drc_drrb;
543	int error;
544	ds_hold_flags_t dsflags = 0;
545	uint64_t featureflags = DMU_GET_FEATUREFLAGS(drrb->drr_versioninfo);
546	dsl_dataset_t *ds;
547	const char *tofs = drba->drba_cookie->drc_tofs;
548
549	/* 6 extra bytes for /%recv */
550	char recvname[ZFS_MAX_DATASET_NAME_LEN + 6];
551
552	/* already checked */
553	ASSERT3U(drrb->drr_magic, ==, DMU_BACKUP_MAGIC);
554	ASSERT(featureflags & DMU_BACKUP_FEATURE_RESUMING);
555
556	if (DMU_GET_STREAM_HDRTYPE(drrb->drr_versioninfo) ==
557	    DMU_COMPOUNDSTREAM ||
558	    drrb->drr_type >= DMU_OST_NUMTYPES)
559		return (SET_ERROR(EINVAL));
560
561	/* Verify pool version supports SA if SA_SPILL feature set */
562	if ((featureflags & DMU_BACKUP_FEATURE_SA_SPILL) &&
563	    spa_version(dp->dp_spa) < SPA_VERSION_SA)
564		return (SET_ERROR(ENOTSUP));
565
566	/*
567	 * The receiving code doesn't know how to translate a WRITE_EMBEDDED
568	 * record to a plain WRITE record, so the pool must have the
569	 * EMBEDDED_DATA feature enabled if the stream has WRITE_EMBEDDED
570	 * records.  Same with WRITE_EMBEDDED records that use LZ4 compression.
571	 */
572	if ((featureflags & DMU_BACKUP_FEATURE_EMBED_DATA) &&
573	    !spa_feature_is_enabled(dp->dp_spa, SPA_FEATURE_EMBEDDED_DATA))
574		return (SET_ERROR(ENOTSUP));
575	if ((featureflags & DMU_BACKUP_FEATURE_LZ4) &&
576	    !spa_feature_is_enabled(dp->dp_spa, SPA_FEATURE_LZ4_COMPRESS))
577		return (SET_ERROR(ENOTSUP));
578
579	/*
580	 * The receiving code doesn't know how to translate large blocks
581	 * to smaller ones, so the pool must have the LARGE_BLOCKS
582	 * feature enabled if the stream has LARGE_BLOCKS. Same with
583	 * large dnodes.
584	 */
585	if ((featureflags & DMU_BACKUP_FEATURE_LARGE_BLOCKS) &&
586	    !spa_feature_is_enabled(dp->dp_spa, SPA_FEATURE_LARGE_BLOCKS))
587		return (SET_ERROR(ENOTSUP));
588	if ((featureflags & DMU_BACKUP_FEATURE_LARGE_DNODE) &&
589	    !spa_feature_is_enabled(dp->dp_spa, SPA_FEATURE_LARGE_DNODE))
590		return (SET_ERROR(ENOTSUP));
591
592	(void) snprintf(recvname, sizeof (recvname), "%s/%s",
593	    tofs, recv_clone_name);
594
595	if (featureflags & DMU_BACKUP_FEATURE_RAW) {
596		/* raw receives require spill block allocation flag */
597		if (!(drrb->drr_flags & DRR_FLAG_SPILL_BLOCK))
598			return (SET_ERROR(ZFS_ERR_SPILL_BLOCK_FLAG_MISSING));
599	} else {
600		dsflags |= DS_HOLD_FLAG_DECRYPT;
601	}
602
603	if (dsl_dataset_hold_flags(dp, recvname, dsflags, FTAG, &ds) != 0) {
604		/* %recv does not exist; continue in tofs */
605		error = dsl_dataset_hold_flags(dp, tofs, dsflags, FTAG, &ds);
606		if (error != 0)
607			return (error);
608	}
609
610	/* check that ds is marked inconsistent */
611	if (!DS_IS_INCONSISTENT(ds)) {
612		dsl_dataset_rele_flags(ds, dsflags, FTAG);
613		return (SET_ERROR(EINVAL));
614	}
615
616	/* check that there is resuming data, and that the toguid matches */
617	if (!dsl_dataset_is_zapified(ds)) {
618		dsl_dataset_rele_flags(ds, dsflags, FTAG);
619		return (SET_ERROR(EINVAL));
620	}
621	uint64_t val;
622	error = zap_lookup(dp->dp_meta_objset, ds->ds_object,
623	    DS_FIELD_RESUME_TOGUID, sizeof (val), 1, &val);
624	if (error != 0 || drrb->drr_toguid != val) {
625		dsl_dataset_rele_flags(ds, dsflags, FTAG);
626		return (SET_ERROR(EINVAL));
627	}
628
629	/*
630	 * Check if the receive is still running.  If so, it will be owned.
631	 * Note that nothing else can own the dataset (e.g. after the receive
632	 * fails) because it will be marked inconsistent.
633	 */
634	if (dsl_dataset_has_owner(ds)) {
635		dsl_dataset_rele_flags(ds, dsflags, FTAG);
636		return (SET_ERROR(EBUSY));
637	}
638
639	/* There should not be any snapshots of this fs yet. */
640	if (ds->ds_prev != NULL && ds->ds_prev->ds_dir == ds->ds_dir) {
641		dsl_dataset_rele_flags(ds, dsflags, FTAG);
642		return (SET_ERROR(EINVAL));
643	}
644
645	/*
646	 * Note: resume point will be checked when we process the first WRITE
647	 * record.
648	 */
649
650	/* check that the origin matches */
651	val = 0;
652	(void) zap_lookup(dp->dp_meta_objset, ds->ds_object,
653	    DS_FIELD_RESUME_FROMGUID, sizeof (val), 1, &val);
654	if (drrb->drr_fromguid != val) {
655		dsl_dataset_rele_flags(ds, dsflags, FTAG);
656		return (SET_ERROR(EINVAL));
657	}
658
659	dsl_dataset_rele_flags(ds, dsflags, FTAG);
660	return (0);
661}
662
663static void
664dmu_recv_resume_begin_sync(void *arg, dmu_tx_t *tx)
665{
666	dmu_recv_begin_arg_t *drba = arg;
667	dsl_pool_t *dp = dmu_tx_pool(tx);
668	const char *tofs = drba->drba_cookie->drc_tofs;
669	struct drr_begin *drrb = drba->drba_cookie->drc_drrb;
670	uint64_t featureflags = DMU_GET_FEATUREFLAGS(drrb->drr_versioninfo);
671	dsl_dataset_t *ds;
672	objset_t *os;
673	ds_hold_flags_t dsflags = 0;
674	uint64_t dsobj;
675	/* 6 extra bytes for /%recv */
676	char recvname[ZFS_MAX_DATASET_NAME_LEN + 6];
677
678	(void) snprintf(recvname, sizeof (recvname), "%s/%s",
679	    tofs, recv_clone_name);
680
681	if (featureflags & DMU_BACKUP_FEATURE_RAW) {
682		drba->drba_cookie->drc_raw = B_TRUE;
683	} else {
684		dsflags |= DS_HOLD_FLAG_DECRYPT;
685	}
686
687	if (dsl_dataset_hold_flags(dp, recvname, dsflags, FTAG, &ds) != 0) {
688		/* %recv does not exist; continue in tofs */
689		VERIFY0(dsl_dataset_hold_flags(dp, tofs, dsflags, FTAG, &ds));
690		drba->drba_cookie->drc_newfs = B_TRUE;
691	}
692
693	/* clear the inconsistent flag so that we can own it */
694	ASSERT(DS_IS_INCONSISTENT(ds));
695	dmu_buf_will_dirty(ds->ds_dbuf, tx);
696	dsl_dataset_phys(ds)->ds_flags &= ~DS_FLAG_INCONSISTENT;
697	dsobj = ds->ds_object;
698	dsl_dataset_rele_flags(ds, dsflags, FTAG);
699
700	VERIFY0(dsl_dataset_own_obj(dp, dsobj, dsflags, dmu_recv_tag, &ds));
701	VERIFY0(dmu_objset_from_ds(ds, &os));
702
703	dmu_buf_will_dirty(ds->ds_dbuf, tx);
704	dsl_dataset_phys(ds)->ds_flags |= DS_FLAG_INCONSISTENT;
705
706	rrw_enter(&ds->ds_bp_rwlock, RW_READER, FTAG);
707	ASSERT(!BP_IS_HOLE(dsl_dataset_get_blkptr(ds)) ||
708	    drba->drba_cookie->drc_raw);
709	rrw_exit(&ds->ds_bp_rwlock, FTAG);
710
711	drba->drba_cookie->drc_ds = ds;
712
713	spa_history_log_internal_ds(ds, "resume receive", tx, "");
714}
715
716/*
717 * NB: callers *MUST* call dmu_recv_stream() if dmu_recv_begin()
718 * succeeds; otherwise we will leak the holds on the datasets.
719 */
720int
721dmu_recv_begin(char *tofs, char *tosnap, dmu_replay_record_t *drr_begin,
722    boolean_t force, boolean_t resumable, nvlist_t *localprops,
723    nvlist_t *hidden_args, char *origin, dmu_recv_cookie_t *drc)
724{
725	dmu_recv_begin_arg_t drba = { 0 };
726
727	bzero(drc, sizeof (dmu_recv_cookie_t));
728	drc->drc_drr_begin = drr_begin;
729	drc->drc_drrb = &drr_begin->drr_u.drr_begin;
730	drc->drc_tosnap = tosnap;
731	drc->drc_tofs = tofs;
732	drc->drc_force = force;
733	drc->drc_resumable = resumable;
734	drc->drc_cred = CRED();
735	drc->drc_clone = (origin != NULL);
736
737	if (drc->drc_drrb->drr_magic == BSWAP_64(DMU_BACKUP_MAGIC)) {
738		drc->drc_byteswap = B_TRUE;
739		(void) fletcher_4_incremental_byteswap(drr_begin,
740		    sizeof (dmu_replay_record_t), &drc->drc_cksum);
741		byteswap_record(drr_begin);
742	} else if (drc->drc_drrb->drr_magic == DMU_BACKUP_MAGIC) {
743		(void) fletcher_4_incremental_native(drr_begin,
744		    sizeof (dmu_replay_record_t), &drc->drc_cksum);
745	} else {
746		return (SET_ERROR(EINVAL));
747	}
748
749	if (drc->drc_drrb->drr_flags & DRR_FLAG_SPILL_BLOCK)
750		drc->drc_spill = B_TRUE;
751
752	drba.drba_origin = origin;
753	drba.drba_cookie = drc;
754	drba.drba_cred = CRED();
755
756	if (DMU_GET_FEATUREFLAGS(drc->drc_drrb->drr_versioninfo) &
757	    DMU_BACKUP_FEATURE_RESUMING) {
758		return (dsl_sync_task(tofs,
759		    dmu_recv_resume_begin_check, dmu_recv_resume_begin_sync,
760		    &drba, 5, ZFS_SPACE_CHECK_NORMAL));
761	} else  {
762		int err;
763
764		/*
765		 * For non-raw, non-incremental, non-resuming receives the
766		 * user can specify encryption parameters on the command line
767		 * with "zfs recv -o". For these receives we create a dcp and
768		 * pass it to the sync task. Creating the dcp will implicitly
769		 * remove the encryption params from the localprops nvlist,
770		 * which avoids errors when trying to set these normally
771		 * read-only properties. Any other kind of receive that
772		 * attempts to set these properties will fail as a result.
773		 */
774		if ((DMU_GET_FEATUREFLAGS(drc->drc_drrb->drr_versioninfo) &
775		    DMU_BACKUP_FEATURE_RAW) == 0 &&
776		    origin == NULL && drc->drc_drrb->drr_fromguid == 0) {
777			err = dsl_crypto_params_create_nvlist(DCP_CMD_NONE,
778			    localprops, hidden_args, &drba.drba_dcp);
779			if (err != 0)
780				return (err);
781		}
782
783		err = dsl_sync_task(tofs,
784		    dmu_recv_begin_check, dmu_recv_begin_sync,
785		    &drba, 5, ZFS_SPACE_CHECK_NORMAL);
786		dsl_crypto_params_free(drba.drba_dcp, !!err);
787
788		return (err);
789	}
790}
791
792struct receive_record_arg {
793	dmu_replay_record_t header;
794	void *payload; /* Pointer to a buffer containing the payload */
795	/*
796	 * If the record is a write, pointer to the arc_buf_t containing the
797	 * payload.
798	 */
799	arc_buf_t *arc_buf;
800	int payload_size;
801	uint64_t bytes_read; /* bytes read from stream when record created */
802	boolean_t eos_marker; /* Marks the end of the stream */
803	bqueue_node_t node;
804};
805
806struct receive_writer_arg {
807	objset_t *os;
808	boolean_t byteswap;
809	bqueue_t q;
810
811	/*
812	 * These three args are used to signal to the main thread that we're
813	 * done.
814	 */
815	kmutex_t mutex;
816	kcondvar_t cv;
817	boolean_t done;
818
819	int err;
820	/* A map from guid to dataset to help handle dedup'd streams. */
821	avl_tree_t *guid_to_ds_map;
822	boolean_t resumable;
823	boolean_t raw;		/* DMU_BACKUP_FEATURE_RAW set */
824	boolean_t spill;	/* DRR_FLAG_SPILL_BLOCK set */
825	uint64_t last_object;
826	uint64_t last_offset;
827	uint64_t max_object; /* highest object ID referenced in stream */
828	uint64_t bytes_read; /* bytes read when current record created */
829
830	/* Encryption parameters for the last received DRR_OBJECT_RANGE */
831	boolean_t or_crypt_params_present;
832	uint64_t or_firstobj;
833	uint64_t or_numslots;
834	uint8_t or_salt[ZIO_DATA_SALT_LEN];
835	uint8_t or_iv[ZIO_DATA_IV_LEN];
836	uint8_t or_mac[ZIO_DATA_MAC_LEN];
837	boolean_t or_byteorder;
838};
839
840struct objlist {
841	list_t list; /* List of struct receive_objnode. */
842	/*
843	 * Last object looked up. Used to assert that objects are being looked
844	 * up in ascending order.
845	 */
846	uint64_t last_lookup;
847};
848
849struct receive_objnode {
850	list_node_t node;
851	uint64_t object;
852};
853
854struct receive_arg {
855	objset_t *os;
856	vnode_t *vp; /* The vnode to read the stream from */
857	uint64_t voff; /* The current offset in the stream */
858	uint64_t bytes_read;
859	/*
860	 * A record that has had its payload read in, but hasn't yet been handed
861	 * off to the worker thread.
862	 */
863	struct receive_record_arg *rrd;
864	/* A record that has had its header read in, but not its payload. */
865	struct receive_record_arg *next_rrd;
866	zio_cksum_t cksum;
867	zio_cksum_t prev_cksum;
868	int err;
869	boolean_t byteswap;
870	boolean_t raw;
871	uint64_t featureflags;
872	/* Sorted list of objects not to issue prefetches for. */
873	struct objlist ignore_objlist;
874};
875
876typedef struct guid_map_entry {
877	uint64_t	guid;
878	boolean_t	raw;
879	dsl_dataset_t	*gme_ds;
880	avl_node_t	avlnode;
881} guid_map_entry_t;
882
883static int
884guid_compare(const void *arg1, const void *arg2)
885{
886	const guid_map_entry_t *gmep1 = (const guid_map_entry_t *)arg1;
887	const guid_map_entry_t *gmep2 = (const guid_map_entry_t *)arg2;
888
889	return (TREE_CMP(gmep1->guid, gmep2->guid));
890}
891
892static void
893free_guid_map_onexit(void *arg)
894{
895	avl_tree_t *ca = arg;
896	void *cookie = NULL;
897	guid_map_entry_t *gmep;
898
899	while ((gmep = avl_destroy_nodes(ca, &cookie)) != NULL) {
900		ds_hold_flags_t dsflags = DS_HOLD_FLAG_DECRYPT;
901
902		if (gmep->raw) {
903			gmep->gme_ds->ds_objset->os_raw_receive = B_FALSE;
904			dsflags &= ~DS_HOLD_FLAG_DECRYPT;
905		}
906
907		dsl_dataset_disown(gmep->gme_ds, dsflags, gmep);
908		kmem_free(gmep, sizeof (guid_map_entry_t));
909	}
910	avl_destroy(ca);
911	kmem_free(ca, sizeof (avl_tree_t));
912}
913
914static int
915receive_read(struct receive_arg *ra, int len, void *buf)
916{
917	int done = 0;
918
919	/*
920	 * The code doesn't rely on this (lengths being multiples of 8).  See
921	 * comment in dump_bytes.
922	 */
923	ASSERT(len % 8 == 0 ||
924	    (ra->featureflags & DMU_BACKUP_FEATURE_RAW) != 0);
925
926	while (done < len) {
927		ssize_t resid;
928
929		ra->err = vn_rdwr(UIO_READ, ra->vp,
930		    (char *)buf + done, len - done,
931		    ra->voff, UIO_SYSSPACE, FAPPEND,
932		    RLIM64_INFINITY, CRED(), &resid);
933
934		if (resid == len - done) {
935			/*
936			 * Note: ECKSUM indicates that the receive
937			 * was interrupted and can potentially be resumed.
938			 */
939			ra->err = SET_ERROR(ECKSUM);
940		}
941		ra->voff += len - done - resid;
942		done = len - resid;
943		if (ra->err != 0)
944			return (ra->err);
945	}
946
947	ra->bytes_read += len;
948
949	ASSERT3U(done, ==, len);
950	return (0);
951}
952
953static void
954byteswap_record(dmu_replay_record_t *drr)
955{
956#define	DO64(X) (drr->drr_u.X = BSWAP_64(drr->drr_u.X))
957#define	DO32(X) (drr->drr_u.X = BSWAP_32(drr->drr_u.X))
958	drr->drr_type = BSWAP_32(drr->drr_type);
959	drr->drr_payloadlen = BSWAP_32(drr->drr_payloadlen);
960
961	switch (drr->drr_type) {
962	case DRR_BEGIN:
963		DO64(drr_begin.drr_magic);
964		DO64(drr_begin.drr_versioninfo);
965		DO64(drr_begin.drr_creation_time);
966		DO32(drr_begin.drr_type);
967		DO32(drr_begin.drr_flags);
968		DO64(drr_begin.drr_toguid);
969		DO64(drr_begin.drr_fromguid);
970		break;
971	case DRR_OBJECT:
972		DO64(drr_object.drr_object);
973		DO32(drr_object.drr_type);
974		DO32(drr_object.drr_bonustype);
975		DO32(drr_object.drr_blksz);
976		DO32(drr_object.drr_bonuslen);
977		DO32(drr_object.drr_raw_bonuslen);
978		DO64(drr_object.drr_toguid);
979		DO64(drr_object.drr_maxblkid);
980		break;
981	case DRR_FREEOBJECTS:
982		DO64(drr_freeobjects.drr_firstobj);
983		DO64(drr_freeobjects.drr_numobjs);
984		DO64(drr_freeobjects.drr_toguid);
985		break;
986	case DRR_WRITE:
987		DO64(drr_write.drr_object);
988		DO32(drr_write.drr_type);
989		DO64(drr_write.drr_offset);
990		DO64(drr_write.drr_logical_size);
991		DO64(drr_write.drr_toguid);
992		ZIO_CHECKSUM_BSWAP(&drr->drr_u.drr_write.drr_key.ddk_cksum);
993		DO64(drr_write.drr_key.ddk_prop);
994		DO64(drr_write.drr_compressed_size);
995		break;
996	case DRR_WRITE_BYREF:
997		DO64(drr_write_byref.drr_object);
998		DO64(drr_write_byref.drr_offset);
999		DO64(drr_write_byref.drr_length);
1000		DO64(drr_write_byref.drr_toguid);
1001		DO64(drr_write_byref.drr_refguid);
1002		DO64(drr_write_byref.drr_refobject);
1003		DO64(drr_write_byref.drr_refoffset);
1004		ZIO_CHECKSUM_BSWAP(&drr->drr_u.drr_write_byref.
1005		    drr_key.ddk_cksum);
1006		DO64(drr_write_byref.drr_key.ddk_prop);
1007		break;
1008	case DRR_WRITE_EMBEDDED:
1009		DO64(drr_write_embedded.drr_object);
1010		DO64(drr_write_embedded.drr_offset);
1011		DO64(drr_write_embedded.drr_length);
1012		DO64(drr_write_embedded.drr_toguid);
1013		DO32(drr_write_embedded.drr_lsize);
1014		DO32(drr_write_embedded.drr_psize);
1015		break;
1016	case DRR_FREE:
1017		DO64(drr_free.drr_object);
1018		DO64(drr_free.drr_offset);
1019		DO64(drr_free.drr_length);
1020		DO64(drr_free.drr_toguid);
1021		break;
1022	case DRR_SPILL:
1023		DO64(drr_spill.drr_object);
1024		DO64(drr_spill.drr_length);
1025		DO64(drr_spill.drr_toguid);
1026		DO64(drr_spill.drr_compressed_size);
1027		DO32(drr_spill.drr_type);
1028		break;
1029	case DRR_OBJECT_RANGE:
1030		DO64(drr_object_range.drr_firstobj);
1031		DO64(drr_object_range.drr_numslots);
1032		DO64(drr_object_range.drr_toguid);
1033		break;
1034	case DRR_END:
1035		DO64(drr_end.drr_toguid);
1036		ZIO_CHECKSUM_BSWAP(&drr->drr_u.drr_end.drr_checksum);
1037		break;
1038	}
1039
1040	if (drr->drr_type != DRR_BEGIN) {
1041		ZIO_CHECKSUM_BSWAP(&drr->drr_u.drr_checksum.drr_checksum);
1042	}
1043
1044#undef DO64
1045#undef DO32
1046}
1047
1048static inline uint8_t
1049deduce_nblkptr(dmu_object_type_t bonus_type, uint64_t bonus_size)
1050{
1051	if (bonus_type == DMU_OT_SA) {
1052		return (1);
1053	} else {
1054		return (1 +
1055		    ((DN_OLD_MAX_BONUSLEN -
1056		    MIN(DN_OLD_MAX_BONUSLEN, bonus_size)) >> SPA_BLKPTRSHIFT));
1057	}
1058}
1059
1060static void
1061save_resume_state(struct receive_writer_arg *rwa,
1062    uint64_t object, uint64_t offset, dmu_tx_t *tx)
1063{
1064	int txgoff = dmu_tx_get_txg(tx) & TXG_MASK;
1065
1066	if (!rwa->resumable)
1067		return;
1068
1069	/*
1070	 * We use ds_resume_bytes[] != 0 to indicate that we need to
1071	 * update this on disk, so it must not be 0.
1072	 */
1073	ASSERT(rwa->bytes_read != 0);
1074
1075	/*
1076	 * We only resume from write records, which have a valid
1077	 * (non-meta-dnode) object number.
1078	 */
1079	ASSERT(object != 0);
1080
1081	/*
1082	 * For resuming to work correctly, we must receive records in order,
1083	 * sorted by object,offset.  This is checked by the callers, but
1084	 * assert it here for good measure.
1085	 */
1086	ASSERT3U(object, >=, rwa->os->os_dsl_dataset->ds_resume_object[txgoff]);
1087	ASSERT(object != rwa->os->os_dsl_dataset->ds_resume_object[txgoff] ||
1088	    offset >= rwa->os->os_dsl_dataset->ds_resume_offset[txgoff]);
1089	ASSERT3U(rwa->bytes_read, >=,
1090	    rwa->os->os_dsl_dataset->ds_resume_bytes[txgoff]);
1091
1092	rwa->os->os_dsl_dataset->ds_resume_object[txgoff] = object;
1093	rwa->os->os_dsl_dataset->ds_resume_offset[txgoff] = offset;
1094	rwa->os->os_dsl_dataset->ds_resume_bytes[txgoff] = rwa->bytes_read;
1095}
1096
1097int receive_object_delay_frac = 0;
1098
1099static int
1100receive_object(struct receive_writer_arg *rwa, struct drr_object *drro,
1101    void *data)
1102{
1103	dmu_object_info_t doi;
1104	dmu_tx_t *tx;
1105	uint64_t object;
1106	int err;
1107	uint8_t dn_slots = drro->drr_dn_slots != 0 ?
1108	    drro->drr_dn_slots : DNODE_MIN_SLOTS;
1109
1110	if (receive_object_delay_frac != 0 &&
1111	    spa_get_random(receive_object_delay_frac) == 0)
1112		delay(1);
1113
1114	if (drro->drr_type == DMU_OT_NONE ||
1115	    !DMU_OT_IS_VALID(drro->drr_type) ||
1116	    !DMU_OT_IS_VALID(drro->drr_bonustype) ||
1117	    drro->drr_checksumtype >= ZIO_CHECKSUM_FUNCTIONS ||
1118	    drro->drr_compress >= ZIO_COMPRESS_FUNCTIONS ||
1119	    P2PHASE(drro->drr_blksz, SPA_MINBLOCKSIZE) ||
1120	    drro->drr_blksz < SPA_MINBLOCKSIZE ||
1121	    drro->drr_blksz > spa_maxblocksize(dmu_objset_spa(rwa->os)) ||
1122	    drro->drr_bonuslen >
1123	    DN_BONUS_SIZE(spa_maxdnodesize(dmu_objset_spa(rwa->os))) ||
1124	    dn_slots >
1125	    (spa_maxdnodesize(dmu_objset_spa(rwa->os)) >> DNODE_SHIFT)) {
1126		return (SET_ERROR(EINVAL));
1127	}
1128
1129	if (rwa->raw) {
1130		/*
1131		 * We should have received a DRR_OBJECT_RANGE record
1132		 * containing this block and stored it in rwa.
1133		 */
1134		if (drro->drr_object < rwa->or_firstobj ||
1135		    drro->drr_object >= rwa->or_firstobj + rwa->or_numslots ||
1136		    drro->drr_raw_bonuslen < drro->drr_bonuslen ||
1137		    drro->drr_indblkshift > SPA_MAXBLOCKSHIFT ||
1138		    drro->drr_nlevels > DN_MAX_LEVELS ||
1139		    drro->drr_nblkptr > DN_MAX_NBLKPTR ||
1140		    DN_SLOTS_TO_BONUSLEN(drro->drr_dn_slots) <
1141		    drro->drr_raw_bonuslen)
1142			return (SET_ERROR(EINVAL));
1143	} else {
1144
1145		/*
1146		 * The DRR_OBJECT_SPILL flag is valid when the DRR_BEGIN
1147		 * record indicates this by setting DRR_FLAG_SPILL_BLOCK.
1148		 */
1149		if (((drro->drr_flags & ~(DRR_OBJECT_SPILL))) ||
1150		    (!rwa->spill && DRR_OBJECT_HAS_SPILL(drro->drr_flags))) {
1151			return (SET_ERROR(EINVAL));
1152		}
1153
1154		if (drro->drr_raw_bonuslen != 0 || drro->drr_nblkptr != 0 ||
1155		    drro->drr_indblkshift != 0 || drro->drr_nlevels != 0) {
1156			return (SET_ERROR(EINVAL));
1157		}
1158	}
1159
1160	err = dmu_object_info(rwa->os, drro->drr_object, &doi);
1161
1162	if (err != 0 && err != ENOENT && err != EEXIST)
1163		return (SET_ERROR(EINVAL));
1164
1165	if (drro->drr_object > rwa->max_object)
1166		rwa->max_object = drro->drr_object;
1167
1168	/*
1169	 * If we are losing blkptrs or changing the block size this must
1170	 * be a new file instance.  We must clear out the previous file
1171	 * contents before we can change this type of metadata in the dnode.
1172	 * Raw receives will also check that the indirect structure of the
1173	 * dnode hasn't changed.
1174	 */
1175	if (err == 0) {
1176		uint32_t indblksz = drro->drr_indblkshift ?
1177		    1ULL << drro->drr_indblkshift : 0;
1178		int nblkptr = deduce_nblkptr(drro->drr_bonustype,
1179		    drro->drr_bonuslen);
1180		boolean_t did_free = B_FALSE;
1181
1182		object = drro->drr_object;
1183
1184		/* nblkptr should be bounded by the bonus size and type */
1185		if (rwa->raw && nblkptr != drro->drr_nblkptr)
1186			return (SET_ERROR(EINVAL));
1187
1188		/*
1189		 * Check for indicators that the object was freed and
1190		 * reallocated. For all sends, these indicators are:
1191		 *	- A changed block size
1192		 *	- A smaller nblkptr
1193		 *	- A changed dnode size
1194		 * For raw sends we also check a few other fields to
1195		 * ensure we are preserving the objset structure exactly
1196		 * as it was on the receive side:
1197		 *	- A changed indirect block size
1198		 *	- A smaller nlevels
1199		 */
1200		if (drro->drr_blksz != doi.doi_data_block_size ||
1201		    nblkptr < doi.doi_nblkptr ||
1202		    dn_slots != doi.doi_dnodesize >> DNODE_SHIFT ||
1203		    (rwa->raw &&
1204		    (indblksz != doi.doi_metadata_block_size ||
1205		    drro->drr_nlevels < doi.doi_indirection))) {
1206			err = dmu_free_long_range(rwa->os,
1207			    drro->drr_object, 0, DMU_OBJECT_END);
1208			if (err != 0)
1209				return (SET_ERROR(EINVAL));
1210			else
1211				did_free = B_TRUE;
1212		}
1213
1214		/*
1215		 * The dmu does not currently support decreasing nlevels
1216		 * or changing the number of dnode slots on an object. For
1217		 * non-raw sends, this does not matter and the new object
1218		 * can just use the previous one's nlevels. For raw sends,
1219		 * however, the structure of the received dnode (including
1220		 * nlevels and dnode slots) must match that of the send
1221		 * side. Therefore, instead of using dmu_object_reclaim(),
1222		 * we must free the object completely and call
1223		 * dmu_object_claim_dnsize() instead.
1224		 */
1225		if ((rwa->raw && drro->drr_nlevels < doi.doi_indirection) ||
1226		    dn_slots != doi.doi_dnodesize >> DNODE_SHIFT) {
1227			err = dmu_free_long_object(rwa->os, drro->drr_object);
1228			if (err != 0)
1229				return (SET_ERROR(EINVAL));
1230
1231			txg_wait_synced(dmu_objset_pool(rwa->os), 0);
1232			object = DMU_NEW_OBJECT;
1233		}
1234
1235		/*
1236		 * For raw receives, free everything beyond the new incoming
1237		 * maxblkid. Normally this would be done with a DRR_FREE
1238		 * record that would come after this DRR_OBJECT record is
1239		 * processed. However, for raw receives we manually set the
1240		 * maxblkid from the drr_maxblkid and so we must first free
1241		 * everything above that blkid to ensure the DMU is always
1242		 * consistent with itself. We will never free the first block
1243		 * of the object here because a maxblkid of 0 could indicate
1244		 * an object with a single block or one with no blocks. This
1245		 * free may be skipped when dmu_free_long_range() was called
1246		 * above since it covers the entire object's contents.
1247		 */
1248		if (rwa->raw && object != DMU_NEW_OBJECT && !did_free) {
1249			err = dmu_free_long_range(rwa->os, drro->drr_object,
1250			    (drro->drr_maxblkid + 1) * doi.doi_data_block_size,
1251			    DMU_OBJECT_END);
1252			if (err != 0)
1253				return (SET_ERROR(EINVAL));
1254		}
1255	} else if (err == EEXIST) {
1256		/*
1257		 * The object requested is currently an interior slot of a
1258		 * multi-slot dnode. This will be resolved when the next txg
1259		 * is synced out, since the send stream will have told us
1260		 * to free this slot when we freed the associated dnode
1261		 * earlier in the stream.
1262		 */
1263		txg_wait_synced(dmu_objset_pool(rwa->os), 0);
1264
1265		if (dmu_object_info(rwa->os, drro->drr_object, NULL) != ENOENT)
1266			return (SET_ERROR(EINVAL));
1267
1268		/* object was freed and we are about to allocate a new one */
1269		object = DMU_NEW_OBJECT;
1270	} else {
1271		/* object is free and we are about to allocate a new one */
1272		object = DMU_NEW_OBJECT;
1273	}
1274
1275	/*
1276	 * If this is a multi-slot dnode there is a chance that this
1277	 * object will expand into a slot that is already used by
1278	 * another object from the previous snapshot. We must free
1279	 * these objects before we attempt to allocate the new dnode.
1280	 */
1281	if (dn_slots > 1) {
1282		boolean_t need_sync = B_FALSE;
1283
1284		for (uint64_t slot = drro->drr_object + 1;
1285		    slot < drro->drr_object + dn_slots;
1286		    slot++) {
1287			dmu_object_info_t slot_doi;
1288
1289			err = dmu_object_info(rwa->os, slot, &slot_doi);
1290			if (err == ENOENT || err == EEXIST)
1291				continue;
1292			else if (err != 0)
1293				return (err);
1294
1295			err = dmu_free_long_object(rwa->os, slot);
1296
1297			if (err != 0)
1298				return (err);
1299
1300			need_sync = B_TRUE;
1301		}
1302
1303		if (need_sync)
1304			txg_wait_synced(dmu_objset_pool(rwa->os), 0);
1305	}
1306
1307	tx = dmu_tx_create(rwa->os);
1308	dmu_tx_hold_bonus(tx, object);
1309	dmu_tx_hold_write(tx, object, 0, 0);
1310	err = dmu_tx_assign(tx, TXG_WAIT);
1311	if (err != 0) {
1312		dmu_tx_abort(tx);
1313		return (err);
1314	}
1315
1316	if (object == DMU_NEW_OBJECT) {
1317		/* Currently free, wants to be allocated */
1318		err = dmu_object_claim_dnsize(rwa->os, drro->drr_object,
1319		    drro->drr_type, drro->drr_blksz,
1320		    drro->drr_bonustype, drro->drr_bonuslen,
1321		    dn_slots << DNODE_SHIFT, tx);
1322	} else if (drro->drr_type != doi.doi_type ||
1323	    drro->drr_blksz != doi.doi_data_block_size ||
1324	    drro->drr_bonustype != doi.doi_bonus_type ||
1325	    drro->drr_bonuslen != doi.doi_bonus_size) {
1326		/* Currently allocated, but with different properties */
1327		err = dmu_object_reclaim_dnsize(rwa->os, drro->drr_object,
1328		    drro->drr_type, drro->drr_blksz,
1329		    drro->drr_bonustype, drro->drr_bonuslen,
1330		    dn_slots << DNODE_SHIFT, rwa->spill ?
1331		    DRR_OBJECT_HAS_SPILL(drro->drr_flags) : B_FALSE, tx);
1332	} else if (rwa->spill && !DRR_OBJECT_HAS_SPILL(drro->drr_flags)) {
1333		/*
1334		 * Currently allocated, the existing version of this object
1335		 * may reference a spill block that is no longer allocated
1336		 * at the source and needs to be freed.
1337		 */
1338		err = dmu_object_rm_spill(rwa->os, drro->drr_object, tx);
1339	}
1340
1341	if (err != 0) {
1342		dmu_tx_commit(tx);
1343		return (SET_ERROR(EINVAL));
1344	}
1345
1346	if (rwa->or_crypt_params_present) {
1347		/*
1348		 * Set the crypt params for the buffer associated with this
1349		 * range of dnodes.  This causes the blkptr_t to have the
1350		 * same crypt params (byteorder, salt, iv, mac) as on the
1351		 * sending side.
1352		 *
1353		 * Since we are committing this tx now, it is possible for
1354		 * the dnode block to end up on-disk with the incorrect MAC,
1355		 * if subsequent objects in this block are received in a
1356		 * different txg.  However, since the dataset is marked as
1357		 * inconsistent, no code paths will do a non-raw read (or
1358		 * decrypt the block / verify the MAC). The receive code and
1359		 * scrub code can safely do raw reads and verify the
1360		 * checksum.  They don't need to verify the MAC.
1361		 */
1362		dmu_buf_t *db = NULL;
1363		uint64_t offset = rwa->or_firstobj * DNODE_MIN_SIZE;
1364
1365		err = dmu_buf_hold_by_dnode(DMU_META_DNODE(rwa->os),
1366		    offset, FTAG, &db, DMU_READ_PREFETCH | DMU_READ_NO_DECRYPT);
1367		if (err != 0) {
1368			dmu_tx_commit(tx);
1369			return (SET_ERROR(EINVAL));
1370		}
1371
1372		dmu_buf_set_crypt_params(db, rwa->or_byteorder,
1373		    rwa->or_salt, rwa->or_iv, rwa->or_mac, tx);
1374
1375		dmu_buf_rele(db, FTAG);
1376
1377		rwa->or_crypt_params_present = B_FALSE;
1378	}
1379
1380	dmu_object_set_checksum(rwa->os, drro->drr_object,
1381	    drro->drr_checksumtype, tx);
1382	dmu_object_set_compress(rwa->os, drro->drr_object,
1383	    drro->drr_compress, tx);
1384
1385	/* handle more restrictive dnode structuring for raw recvs */
1386	if (rwa->raw) {
1387		/*
1388		 * Set the indirect block size, block shift, nlevels.
1389		 * This will not fail because we ensured all of the
1390		 * blocks were freed earlier if this is a new object.
1391		 * For non-new objects block size and indirect block
1392		 * shift cannot change and nlevels can only increase.
1393		 */
1394		VERIFY0(dmu_object_set_blocksize(rwa->os, drro->drr_object,
1395		    drro->drr_blksz, drro->drr_indblkshift, tx));
1396		VERIFY0(dmu_object_set_nlevels(rwa->os, drro->drr_object,
1397		    drro->drr_nlevels, tx));
1398
1399		/*
1400		 * Set the maxblkid. This will always succeed because
1401		 * we freed all blocks beyond the new maxblkid above.
1402		 */
1403		VERIFY0(dmu_object_set_maxblkid(rwa->os, drro->drr_object,
1404		    drro->drr_maxblkid, tx));
1405	}
1406
1407	if (data != NULL) {
1408		dmu_buf_t *db;
1409		dnode_t *dn;
1410		uint32_t flags = DMU_READ_NO_PREFETCH;
1411
1412		if (rwa->raw)
1413			flags |= DMU_READ_NO_DECRYPT;
1414
1415		VERIFY0(dnode_hold(rwa->os, drro->drr_object, FTAG, &dn));
1416		VERIFY0(dmu_bonus_hold_by_dnode(dn, FTAG, &db, flags));
1417
1418		dmu_buf_will_dirty(db, tx);
1419
1420		ASSERT3U(db->db_size, >=, drro->drr_bonuslen);
1421		bcopy(data, db->db_data, DRR_OBJECT_PAYLOAD_SIZE(drro));
1422
1423		/*
1424		 * Raw bonus buffers have their byteorder determined by the
1425		 * DRR_OBJECT_RANGE record.
1426		 */
1427		if (rwa->byteswap && !rwa->raw) {
1428			dmu_object_byteswap_t byteswap =
1429			    DMU_OT_BYTESWAP(drro->drr_bonustype);
1430			dmu_ot_byteswap[byteswap].ob_func(db->db_data,
1431			    DRR_OBJECT_PAYLOAD_SIZE(drro));
1432		}
1433		dmu_buf_rele(db, FTAG);
1434		dnode_rele(dn, FTAG);
1435	}
1436	dmu_tx_commit(tx);
1437
1438	return (0);
1439}
1440
1441/* ARGSUSED */
1442static int
1443receive_freeobjects(struct receive_writer_arg *rwa,
1444    struct drr_freeobjects *drrfo)
1445{
1446	uint64_t obj;
1447	int next_err = 0;
1448
1449	if (drrfo->drr_firstobj + drrfo->drr_numobjs < drrfo->drr_firstobj)
1450		return (SET_ERROR(EINVAL));
1451
1452	for (obj = drrfo->drr_firstobj == 0 ? 1 : drrfo->drr_firstobj;
1453	    obj < drrfo->drr_firstobj + drrfo->drr_numobjs && next_err == 0;
1454	    next_err = dmu_object_next(rwa->os, &obj, FALSE, 0)) {
1455		dmu_object_info_t doi;
1456		int err;
1457
1458		err = dmu_object_info(rwa->os, obj, &doi);
1459		if (err == ENOENT)
1460			continue;
1461		else if (err != 0)
1462			return (err);
1463
1464		err = dmu_free_long_object(rwa->os, obj);
1465
1466		if (err != 0)
1467			return (err);
1468
1469		if (obj > rwa->max_object)
1470			rwa->max_object = obj;
1471	}
1472	if (next_err != ESRCH)
1473		return (next_err);
1474	return (0);
1475}
1476
1477static int
1478receive_write(struct receive_writer_arg *rwa, struct drr_write *drrw,
1479    arc_buf_t *abuf)
1480{
1481	int err;
1482	dmu_tx_t *tx;
1483	dnode_t *dn;
1484
1485	if (drrw->drr_offset + drrw->drr_logical_size < drrw->drr_offset ||
1486	    !DMU_OT_IS_VALID(drrw->drr_type))
1487		return (SET_ERROR(EINVAL));
1488
1489	/*
1490	 * For resuming to work, records must be in increasing order
1491	 * by (object, offset).
1492	 */
1493	if (drrw->drr_object < rwa->last_object ||
1494	    (drrw->drr_object == rwa->last_object &&
1495	    drrw->drr_offset < rwa->last_offset)) {
1496		return (SET_ERROR(EINVAL));
1497	}
1498	rwa->last_object = drrw->drr_object;
1499	rwa->last_offset = drrw->drr_offset;
1500
1501	if (rwa->last_object > rwa->max_object)
1502		rwa->max_object = rwa->last_object;
1503
1504	if (dmu_object_info(rwa->os, drrw->drr_object, NULL) != 0)
1505		return (SET_ERROR(EINVAL));
1506
1507	tx = dmu_tx_create(rwa->os);
1508	dmu_tx_hold_write(tx, drrw->drr_object,
1509	    drrw->drr_offset, drrw->drr_logical_size);
1510	err = dmu_tx_assign(tx, TXG_WAIT);
1511	if (err != 0) {
1512		dmu_tx_abort(tx);
1513		return (err);
1514	}
1515
1516	if (rwa->byteswap && !arc_is_encrypted(abuf) &&
1517	    arc_get_compression(abuf) == ZIO_COMPRESS_OFF) {
1518		dmu_object_byteswap_t byteswap =
1519		    DMU_OT_BYTESWAP(drrw->drr_type);
1520		dmu_ot_byteswap[byteswap].ob_func(abuf->b_data,
1521		    DRR_WRITE_PAYLOAD_SIZE(drrw));
1522	}
1523
1524	VERIFY0(dnode_hold(rwa->os, drrw->drr_object, FTAG, &dn));
1525	err = dmu_assign_arcbuf_by_dnode(dn, drrw->drr_offset, abuf, tx);
1526	if (err != 0) {
1527		dnode_rele(dn, FTAG);
1528		dmu_tx_commit(tx);
1529		return (err);
1530	}
1531	dnode_rele(dn, FTAG);
1532
1533	/*
1534	 * Note: If the receive fails, we want the resume stream to start
1535	 * with the same record that we last successfully received (as opposed
1536	 * to the next record), so that we can verify that we are
1537	 * resuming from the correct location.
1538	 */
1539	save_resume_state(rwa, drrw->drr_object, drrw->drr_offset, tx);
1540	dmu_tx_commit(tx);
1541
1542	return (0);
1543}
1544
1545/*
1546 * Handle a DRR_WRITE_BYREF record.  This record is used in dedup'ed
1547 * streams to refer to a copy of the data that is already on the
1548 * system because it came in earlier in the stream.  This function
1549 * finds the earlier copy of the data, and uses that copy instead of
1550 * data from the stream to fulfill this write.
1551 */
1552static int
1553receive_write_byref(struct receive_writer_arg *rwa,
1554    struct drr_write_byref *drrwbr)
1555{
1556	dmu_tx_t *tx;
1557	int err;
1558	guid_map_entry_t gmesrch;
1559	guid_map_entry_t *gmep;
1560	avl_index_t where;
1561	objset_t *ref_os = NULL;
1562	int flags = DMU_READ_PREFETCH;
1563	dmu_buf_t *dbp;
1564
1565	if (drrwbr->drr_offset + drrwbr->drr_length < drrwbr->drr_offset)
1566		return (SET_ERROR(EINVAL));
1567
1568	/*
1569	 * If the GUID of the referenced dataset is different from the
1570	 * GUID of the target dataset, find the referenced dataset.
1571	 */
1572	if (drrwbr->drr_toguid != drrwbr->drr_refguid) {
1573		gmesrch.guid = drrwbr->drr_refguid;
1574		if ((gmep = avl_find(rwa->guid_to_ds_map, &gmesrch,
1575		    &where)) == NULL) {
1576			return (SET_ERROR(EINVAL));
1577		}
1578		if (dmu_objset_from_ds(gmep->gme_ds, &ref_os))
1579			return (SET_ERROR(EINVAL));
1580	} else {
1581		ref_os = rwa->os;
1582	}
1583
1584	if (drrwbr->drr_object > rwa->max_object)
1585		rwa->max_object = drrwbr->drr_object;
1586
1587	if (rwa->raw)
1588		flags |= DMU_READ_NO_DECRYPT;
1589
1590	/* may return either a regular db or an encrypted one */
1591	err = dmu_buf_hold(ref_os, drrwbr->drr_refobject,
1592	    drrwbr->drr_refoffset, FTAG, &dbp, flags);
1593	if (err != 0)
1594		return (err);
1595
1596	tx = dmu_tx_create(rwa->os);
1597
1598	dmu_tx_hold_write(tx, drrwbr->drr_object,
1599	    drrwbr->drr_offset, drrwbr->drr_length);
1600	err = dmu_tx_assign(tx, TXG_WAIT);
1601	if (err != 0) {
1602		dmu_tx_abort(tx);
1603		return (err);
1604	}
1605
1606	if (rwa->raw) {
1607		dmu_copy_from_buf(rwa->os, drrwbr->drr_object,
1608		    drrwbr->drr_offset, dbp, tx);
1609	} else {
1610		dmu_write(rwa->os, drrwbr->drr_object,
1611		    drrwbr->drr_offset, drrwbr->drr_length, dbp->db_data, tx);
1612	}
1613	dmu_buf_rele(dbp, FTAG);
1614
1615	/* See comment in restore_write. */
1616	save_resume_state(rwa, drrwbr->drr_object, drrwbr->drr_offset, tx);
1617	dmu_tx_commit(tx);
1618	return (0);
1619}
1620
1621static int
1622receive_write_embedded(struct receive_writer_arg *rwa,
1623    struct drr_write_embedded *drrwe, void *data)
1624{
1625	dmu_tx_t *tx;
1626	int err;
1627
1628	if (drrwe->drr_offset + drrwe->drr_length < drrwe->drr_offset)
1629		return (EINVAL);
1630
1631	if (drrwe->drr_psize > BPE_PAYLOAD_SIZE)
1632		return (EINVAL);
1633
1634	if (drrwe->drr_etype >= NUM_BP_EMBEDDED_TYPES)
1635		return (EINVAL);
1636	if (drrwe->drr_compression >= ZIO_COMPRESS_FUNCTIONS)
1637		return (EINVAL);
1638	if (rwa->raw)
1639		return (SET_ERROR(EINVAL));
1640
1641	if (drrwe->drr_object > rwa->max_object)
1642		rwa->max_object = drrwe->drr_object;
1643
1644	tx = dmu_tx_create(rwa->os);
1645
1646	dmu_tx_hold_write(tx, drrwe->drr_object,
1647	    drrwe->drr_offset, drrwe->drr_length);
1648	err = dmu_tx_assign(tx, TXG_WAIT);
1649	if (err != 0) {
1650		dmu_tx_abort(tx);
1651		return (err);
1652	}
1653
1654	dmu_write_embedded(rwa->os, drrwe->drr_object,
1655	    drrwe->drr_offset, data, drrwe->drr_etype,
1656	    drrwe->drr_compression, drrwe->drr_lsize, drrwe->drr_psize,
1657	    rwa->byteswap ^ ZFS_HOST_BYTEORDER, tx);
1658
1659	/* See comment in restore_write. */
1660	save_resume_state(rwa, drrwe->drr_object, drrwe->drr_offset, tx);
1661	dmu_tx_commit(tx);
1662	return (0);
1663}
1664
1665static int
1666receive_spill(struct receive_writer_arg *rwa, struct drr_spill *drrs,
1667    arc_buf_t *abuf)
1668{
1669	dmu_tx_t *tx;
1670	dmu_buf_t *db, *db_spill;
1671	int err;
1672	uint32_t flags = 0;
1673
1674	if (drrs->drr_length < SPA_MINBLOCKSIZE ||
1675	    drrs->drr_length > spa_maxblocksize(dmu_objset_spa(rwa->os)))
1676		return (SET_ERROR(EINVAL));
1677
1678	/*
1679	 * This is an unmodified spill block which was added to the stream
1680	 * to resolve an issue with incorrectly removing spill blocks.  It
1681	 * should be ignored by current versions of the code which support
1682	 * the DRR_FLAG_SPILL_BLOCK flag.
1683	 */
1684	if (rwa->spill && DRR_SPILL_IS_UNMODIFIED(drrs->drr_flags)) {
1685		dmu_return_arcbuf(abuf);
1686		return (0);
1687	}
1688
1689	if (rwa->raw) {
1690		if (!DMU_OT_IS_VALID(drrs->drr_type) ||
1691		    drrs->drr_compressiontype >= ZIO_COMPRESS_FUNCTIONS ||
1692		    drrs->drr_compressed_size == 0)
1693			return (SET_ERROR(EINVAL));
1694
1695		flags |= DMU_READ_NO_DECRYPT;
1696	}
1697
1698	if (dmu_object_info(rwa->os, drrs->drr_object, NULL) != 0)
1699		return (SET_ERROR(EINVAL));
1700
1701	if (drrs->drr_object > rwa->max_object)
1702		rwa->max_object = drrs->drr_object;
1703
1704	VERIFY0(dmu_bonus_hold(rwa->os, drrs->drr_object, FTAG, &db));
1705	if ((err = dmu_spill_hold_by_bonus(db, DMU_READ_NO_DECRYPT, FTAG,
1706	    &db_spill)) != 0) {
1707		dmu_buf_rele(db, FTAG);
1708		return (err);
1709	}
1710
1711	tx = dmu_tx_create(rwa->os);
1712
1713	dmu_tx_hold_spill(tx, db->db_object);
1714
1715	err = dmu_tx_assign(tx, TXG_WAIT);
1716	if (err != 0) {
1717		dmu_buf_rele(db, FTAG);
1718		dmu_buf_rele(db_spill, FTAG);
1719		dmu_tx_abort(tx);
1720		return (err);
1721	}
1722
1723	/*
1724	 * Spill blocks may both grow and shrink.  When a change in size
1725	 * occurs any existing dbuf must be updated to match the logical
1726	 * size of the provided arc_buf_t.
1727	 */
1728	if (db_spill->db_size != drrs->drr_length) {
1729		dmu_buf_will_fill(db_spill, tx);
1730		VERIFY(0 == dbuf_spill_set_blksz(db_spill,
1731		    drrs->drr_length, tx));
1732	}
1733
1734	if (rwa->byteswap && !arc_is_encrypted(abuf) &&
1735	    arc_get_compression(abuf) == ZIO_COMPRESS_OFF) {
1736		dmu_object_byteswap_t byteswap =
1737		    DMU_OT_BYTESWAP(drrs->drr_type);
1738		dmu_ot_byteswap[byteswap].ob_func(abuf->b_data,
1739		    DRR_SPILL_PAYLOAD_SIZE(drrs));
1740	}
1741
1742	dbuf_assign_arcbuf((dmu_buf_impl_t *)db_spill, abuf, tx);
1743
1744	dmu_buf_rele(db, FTAG);
1745	dmu_buf_rele(db_spill, FTAG);
1746
1747	dmu_tx_commit(tx);
1748	return (0);
1749}
1750
1751/* ARGSUSED */
1752static int
1753receive_free(struct receive_writer_arg *rwa, struct drr_free *drrf)
1754{
1755	int err;
1756
1757	if (drrf->drr_length != DMU_OBJECT_END &&
1758	    drrf->drr_offset + drrf->drr_length < drrf->drr_offset)
1759		return (SET_ERROR(EINVAL));
1760
1761	if (dmu_object_info(rwa->os, drrf->drr_object, NULL) != 0)
1762		return (SET_ERROR(EINVAL));
1763
1764	if (drrf->drr_object > rwa->max_object)
1765		rwa->max_object = drrf->drr_object;
1766
1767	err = dmu_free_long_range(rwa->os, drrf->drr_object,
1768	    drrf->drr_offset, drrf->drr_length);
1769
1770	return (err);
1771}
1772
1773static int
1774receive_object_range(struct receive_writer_arg *rwa,
1775    struct drr_object_range *drror)
1776{
1777	/*
1778	 * By default, we assume this block is in our native format
1779	 * (ZFS_HOST_BYTEORDER). We then take into account whether
1780	 * the send stream is byteswapped (rwa->byteswap). Finally,
1781	 * we need to byteswap again if this particular block was
1782	 * in non-native format on the send side.
1783	 */
1784	boolean_t byteorder = ZFS_HOST_BYTEORDER ^ rwa->byteswap ^
1785	    !!DRR_IS_RAW_BYTESWAPPED(drror->drr_flags);
1786
1787	/*
1788	 * Since dnode block sizes are constant, we should not need to worry
1789	 * about making sure that the dnode block size is the same on the
1790	 * sending and receiving sides for the time being. For non-raw sends,
1791	 * this does not matter (and in fact we do not send a DRR_OBJECT_RANGE
1792	 * record at all). Raw sends require this record type because the
1793	 * encryption parameters are used to protect an entire block of bonus
1794	 * buffers. If the size of dnode blocks ever becomes variable,
1795	 * handling will need to be added to ensure that dnode block sizes
1796	 * match on the sending and receiving side.
1797	 */
1798	if (drror->drr_numslots != DNODES_PER_BLOCK ||
1799	    P2PHASE(drror->drr_firstobj, DNODES_PER_BLOCK) != 0 ||
1800	    !rwa->raw)
1801		return (SET_ERROR(EINVAL));
1802
1803	if (drror->drr_firstobj > rwa->max_object)
1804		rwa->max_object = drror->drr_firstobj;
1805
1806	/*
1807	 * The DRR_OBJECT_RANGE handling must be deferred to receive_object()
1808	 * so that the block of dnodes is not written out when it's empty,
1809	 * and converted to a HOLE BP.
1810	 */
1811	rwa->or_crypt_params_present = B_TRUE;
1812	rwa->or_firstobj = drror->drr_firstobj;
1813	rwa->or_numslots = drror->drr_numslots;
1814	bcopy(drror->drr_salt, rwa->or_salt, ZIO_DATA_SALT_LEN);
1815	bcopy(drror->drr_iv, rwa->or_iv, ZIO_DATA_IV_LEN);
1816	bcopy(drror->drr_mac, rwa->or_mac, ZIO_DATA_MAC_LEN);
1817	rwa->or_byteorder = byteorder;
1818
1819	return (0);
1820}
1821
1822/* used to destroy the drc_ds on error */
1823static void
1824dmu_recv_cleanup_ds(dmu_recv_cookie_t *drc)
1825{
1826	dsl_dataset_t *ds = drc->drc_ds;
1827	ds_hold_flags_t dsflags = (drc->drc_raw) ? 0 : DS_HOLD_FLAG_DECRYPT;
1828
1829	/*
1830	 * Wait for the txg sync before cleaning up the receive. For
1831	 * resumable receives, this ensures that our resume state has
1832	 * been written out to disk. For raw receives, this ensures
1833	 * that the user accounting code will not attempt to do anything
1834	 * after we stopped receiving the dataset.
1835	 */
1836	txg_wait_synced(ds->ds_dir->dd_pool, 0);
1837	ds->ds_objset->os_raw_receive = B_FALSE;
1838
1839	rrw_enter(&ds->ds_bp_rwlock, RW_READER, FTAG);
1840	if (drc->drc_resumable && !BP_IS_HOLE(dsl_dataset_get_blkptr(ds))) {
1841		rrw_exit(&ds->ds_bp_rwlock, FTAG);
1842		dsl_dataset_disown(ds, dsflags, dmu_recv_tag);
1843	} else {
1844		char name[ZFS_MAX_DATASET_NAME_LEN];
1845		rrw_exit(&ds->ds_bp_rwlock, FTAG);
1846		dsl_dataset_name(ds, name);
1847		dsl_dataset_disown(ds, dsflags, dmu_recv_tag);
1848		(void) dsl_destroy_head(name);
1849	}
1850}
1851
1852static void
1853receive_cksum(struct receive_arg *ra, int len, void *buf)
1854{
1855	if (ra->byteswap) {
1856		(void) fletcher_4_incremental_byteswap(buf, len, &ra->cksum);
1857	} else {
1858		(void) fletcher_4_incremental_native(buf, len, &ra->cksum);
1859	}
1860}
1861
1862/*
1863 * Read the payload into a buffer of size len, and update the current record's
1864 * payload field.
1865 * Allocate ra->next_rrd and read the next record's header into
1866 * ra->next_rrd->header.
1867 * Verify checksum of payload and next record.
1868 */
1869static int
1870receive_read_payload_and_next_header(struct receive_arg *ra, int len, void *buf)
1871{
1872	int err;
1873
1874	if (len != 0) {
1875		ASSERT3U(len, <=, SPA_MAXBLOCKSIZE);
1876		err = receive_read(ra, len, buf);
1877		if (err != 0)
1878			return (err);
1879		receive_cksum(ra, len, buf);
1880
1881		/* note: rrd is NULL when reading the begin record's payload */
1882		if (ra->rrd != NULL) {
1883			ra->rrd->payload = buf;
1884			ra->rrd->payload_size = len;
1885			ra->rrd->bytes_read = ra->bytes_read;
1886		}
1887	}
1888
1889	ra->prev_cksum = ra->cksum;
1890
1891	ra->next_rrd = kmem_zalloc(sizeof (*ra->next_rrd), KM_SLEEP);
1892	err = receive_read(ra, sizeof (ra->next_rrd->header),
1893	    &ra->next_rrd->header);
1894	ra->next_rrd->bytes_read = ra->bytes_read;
1895
1896	if (err != 0) {
1897		kmem_free(ra->next_rrd, sizeof (*ra->next_rrd));
1898		ra->next_rrd = NULL;
1899		return (err);
1900	}
1901	if (ra->next_rrd->header.drr_type == DRR_BEGIN) {
1902		kmem_free(ra->next_rrd, sizeof (*ra->next_rrd));
1903		ra->next_rrd = NULL;
1904		return (SET_ERROR(EINVAL));
1905	}
1906
1907	/*
1908	 * Note: checksum is of everything up to but not including the
1909	 * checksum itself.
1910	 */
1911	ASSERT3U(offsetof(dmu_replay_record_t, drr_u.drr_checksum.drr_checksum),
1912	    ==, sizeof (dmu_replay_record_t) - sizeof (zio_cksum_t));
1913	receive_cksum(ra,
1914	    offsetof(dmu_replay_record_t, drr_u.drr_checksum.drr_checksum),
1915	    &ra->next_rrd->header);
1916
1917	zio_cksum_t cksum_orig =
1918	    ra->next_rrd->header.drr_u.drr_checksum.drr_checksum;
1919	zio_cksum_t *cksump =
1920	    &ra->next_rrd->header.drr_u.drr_checksum.drr_checksum;
1921
1922	if (ra->byteswap)
1923		byteswap_record(&ra->next_rrd->header);
1924
1925	if ((!ZIO_CHECKSUM_IS_ZERO(cksump)) &&
1926	    !ZIO_CHECKSUM_EQUAL(ra->cksum, *cksump)) {
1927		kmem_free(ra->next_rrd, sizeof (*ra->next_rrd));
1928		ra->next_rrd = NULL;
1929		return (SET_ERROR(ECKSUM));
1930	}
1931
1932	receive_cksum(ra, sizeof (cksum_orig), &cksum_orig);
1933
1934	return (0);
1935}
1936
1937static void
1938objlist_create(struct objlist *list)
1939{
1940	list_create(&list->list, sizeof (struct receive_objnode),
1941	    offsetof(struct receive_objnode, node));
1942	list->last_lookup = 0;
1943}
1944
1945static void
1946objlist_destroy(struct objlist *list)
1947{
1948	for (struct receive_objnode *n = list_remove_head(&list->list);
1949	    n != NULL; n = list_remove_head(&list->list)) {
1950		kmem_free(n, sizeof (*n));
1951	}
1952	list_destroy(&list->list);
1953}
1954
1955/*
1956 * This function looks through the objlist to see if the specified object number
1957 * is contained in the objlist.  In the process, it will remove all object
1958 * numbers in the list that are smaller than the specified object number.  Thus,
1959 * any lookup of an object number smaller than a previously looked up object
1960 * number will always return false; therefore, all lookups should be done in
1961 * ascending order.
1962 */
1963static boolean_t
1964objlist_exists(struct objlist *list, uint64_t object)
1965{
1966	struct receive_objnode *node = list_head(&list->list);
1967	ASSERT3U(object, >=, list->last_lookup);
1968	list->last_lookup = object;
1969	while (node != NULL && node->object < object) {
1970		VERIFY3P(node, ==, list_remove_head(&list->list));
1971		kmem_free(node, sizeof (*node));
1972		node = list_head(&list->list);
1973	}
1974	return (node != NULL && node->object == object);
1975}
1976
1977/*
1978 * The objlist is a list of object numbers stored in ascending order.  However,
1979 * the insertion of new object numbers does not seek out the correct location to
1980 * store a new object number; instead, it appends it to the list for simplicity.
1981 * Thus, any users must take care to only insert new object numbers in ascending
1982 * order.
1983 */
1984static void
1985objlist_insert(struct objlist *list, uint64_t object)
1986{
1987	struct receive_objnode *node = kmem_zalloc(sizeof (*node), KM_SLEEP);
1988	node->object = object;
1989#ifdef ZFS_DEBUG
1990	struct receive_objnode *last_object = list_tail(&list->list);
1991	uint64_t last_objnum = (last_object != NULL ? last_object->object : 0);
1992	ASSERT3U(node->object, >, last_objnum);
1993#endif
1994	list_insert_tail(&list->list, node);
1995}
1996
1997/*
1998 * Issue the prefetch reads for any necessary indirect blocks.
1999 *
2000 * We use the object ignore list to tell us whether or not to issue prefetches
2001 * for a given object.  We do this for both correctness (in case the blocksize
2002 * of an object has changed) and performance (if the object doesn't exist, don't
2003 * needlessly try to issue prefetches).  We also trim the list as we go through
2004 * the stream to prevent it from growing to an unbounded size.
2005 *
2006 * The object numbers within will always be in sorted order, and any write
2007 * records we see will also be in sorted order, but they're not sorted with
2008 * respect to each other (i.e. we can get several object records before
2009 * receiving each object's write records).  As a result, once we've reached a
2010 * given object number, we can safely remove any reference to lower object
2011 * numbers in the ignore list. In practice, we receive up to 32 object records
2012 * before receiving write records, so the list can have up to 32 nodes in it.
2013 */
2014/* ARGSUSED */
2015static void
2016receive_read_prefetch(struct receive_arg *ra,
2017    uint64_t object, uint64_t offset, uint64_t length)
2018{
2019	if (!objlist_exists(&ra->ignore_objlist, object)) {
2020		dmu_prefetch(ra->os, object, 1, offset, length,
2021		    ZIO_PRIORITY_SYNC_READ);
2022	}
2023}
2024
2025/*
2026 * Read records off the stream, issuing any necessary prefetches.
2027 */
2028static int
2029receive_read_record(struct receive_arg *ra)
2030{
2031	int err;
2032
2033	switch (ra->rrd->header.drr_type) {
2034	case DRR_OBJECT:
2035	{
2036		struct drr_object *drro = &ra->rrd->header.drr_u.drr_object;
2037		uint32_t size = DRR_OBJECT_PAYLOAD_SIZE(drro);
2038		void *buf = NULL;
2039		dmu_object_info_t doi;
2040
2041		if (size != 0)
2042			buf = kmem_zalloc(size, KM_SLEEP);
2043
2044		err = receive_read_payload_and_next_header(ra, size, buf);
2045		if (err != 0) {
2046			kmem_free(buf, size);
2047			return (err);
2048		}
2049		err = dmu_object_info(ra->os, drro->drr_object, &doi);
2050		/*
2051		 * See receive_read_prefetch for an explanation why we're
2052		 * storing this object in the ignore_obj_list.
2053		 */
2054		if (err == ENOENT || err == EEXIST ||
2055		    (err == 0 && doi.doi_data_block_size != drro->drr_blksz)) {
2056			objlist_insert(&ra->ignore_objlist, drro->drr_object);
2057			err = 0;
2058		}
2059		return (err);
2060	}
2061	case DRR_FREEOBJECTS:
2062	{
2063		err = receive_read_payload_and_next_header(ra, 0, NULL);
2064		return (err);
2065	}
2066	case DRR_WRITE:
2067	{
2068		struct drr_write *drrw = &ra->rrd->header.drr_u.drr_write;
2069		arc_buf_t *abuf;
2070		boolean_t is_meta = DMU_OT_IS_METADATA(drrw->drr_type);
2071
2072		if (ra->raw) {
2073			boolean_t byteorder = ZFS_HOST_BYTEORDER ^
2074			    !!DRR_IS_RAW_BYTESWAPPED(drrw->drr_flags) ^
2075			    ra->byteswap;
2076
2077			abuf = arc_loan_raw_buf(dmu_objset_spa(ra->os),
2078			    drrw->drr_object, byteorder, drrw->drr_salt,
2079			    drrw->drr_iv, drrw->drr_mac, drrw->drr_type,
2080			    drrw->drr_compressed_size, drrw->drr_logical_size,
2081			    drrw->drr_compressiontype);
2082		} else if (DRR_WRITE_COMPRESSED(drrw)) {
2083			ASSERT3U(drrw->drr_compressed_size, >, 0);
2084			ASSERT3U(drrw->drr_logical_size, >=,
2085			    drrw->drr_compressed_size);
2086			ASSERT(!is_meta);
2087			abuf = arc_loan_compressed_buf(
2088			    dmu_objset_spa(ra->os),
2089			    drrw->drr_compressed_size, drrw->drr_logical_size,
2090			    drrw->drr_compressiontype);
2091		} else {
2092			abuf = arc_loan_buf(dmu_objset_spa(ra->os),
2093			    is_meta, drrw->drr_logical_size);
2094		}
2095
2096		err = receive_read_payload_and_next_header(ra,
2097		    DRR_WRITE_PAYLOAD_SIZE(drrw), abuf->b_data);
2098		if (err != 0) {
2099			dmu_return_arcbuf(abuf);
2100			return (err);
2101		}
2102		ra->rrd->arc_buf = abuf;
2103		receive_read_prefetch(ra, drrw->drr_object, drrw->drr_offset,
2104		    drrw->drr_logical_size);
2105		return (err);
2106	}
2107	case DRR_WRITE_BYREF:
2108	{
2109		struct drr_write_byref *drrwb =
2110		    &ra->rrd->header.drr_u.drr_write_byref;
2111		err = receive_read_payload_and_next_header(ra, 0, NULL);
2112		receive_read_prefetch(ra, drrwb->drr_object, drrwb->drr_offset,
2113		    drrwb->drr_length);
2114		return (err);
2115	}
2116	case DRR_WRITE_EMBEDDED:
2117	{
2118		struct drr_write_embedded *drrwe =
2119		    &ra->rrd->header.drr_u.drr_write_embedded;
2120		uint32_t size = P2ROUNDUP(drrwe->drr_psize, 8);
2121		void *buf = kmem_zalloc(size, KM_SLEEP);
2122
2123		err = receive_read_payload_and_next_header(ra, size, buf);
2124		if (err != 0) {
2125			kmem_free(buf, size);
2126			return (err);
2127		}
2128
2129		receive_read_prefetch(ra, drrwe->drr_object, drrwe->drr_offset,
2130		    drrwe->drr_length);
2131		return (err);
2132	}
2133	case DRR_FREE:
2134	{
2135		/*
2136		 * It might be beneficial to prefetch indirect blocks here, but
2137		 * we don't really have the data to decide for sure.
2138		 */
2139		err = receive_read_payload_and_next_header(ra, 0, NULL);
2140		return (err);
2141	}
2142	case DRR_END:
2143	{
2144		struct drr_end *drre = &ra->rrd->header.drr_u.drr_end;
2145		if (!ZIO_CHECKSUM_EQUAL(ra->prev_cksum, drre->drr_checksum))
2146			return (SET_ERROR(ECKSUM));
2147		return (0);
2148	}
2149	case DRR_SPILL:
2150	{
2151		struct drr_spill *drrs = &ra->rrd->header.drr_u.drr_spill;
2152		arc_buf_t *abuf;
2153		int len = DRR_SPILL_PAYLOAD_SIZE(drrs);
2154
2155		/* DRR_SPILL records are either raw or uncompressed */
2156		if (ra->raw) {
2157			boolean_t byteorder = ZFS_HOST_BYTEORDER ^
2158			    !!DRR_IS_RAW_BYTESWAPPED(drrs->drr_flags) ^
2159			    ra->byteswap;
2160
2161			abuf = arc_loan_raw_buf(dmu_objset_spa(ra->os),
2162			    dmu_objset_id(ra->os), byteorder, drrs->drr_salt,
2163			    drrs->drr_iv, drrs->drr_mac, drrs->drr_type,
2164			    drrs->drr_compressed_size, drrs->drr_length,
2165			    drrs->drr_compressiontype);
2166		} else {
2167			abuf = arc_loan_buf(dmu_objset_spa(ra->os),
2168			    DMU_OT_IS_METADATA(drrs->drr_type),
2169			    drrs->drr_length);
2170		}
2171
2172		err = receive_read_payload_and_next_header(ra, len,
2173		    abuf->b_data);
2174		if (err != 0) {
2175			dmu_return_arcbuf(abuf);
2176			return (err);
2177		}
2178		ra->rrd->arc_buf = abuf;
2179		return (err);
2180	}
2181	case DRR_OBJECT_RANGE:
2182	{
2183		err = receive_read_payload_and_next_header(ra, 0, NULL);
2184		return (err);
2185	}
2186	default:
2187		return (SET_ERROR(EINVAL));
2188	}
2189}
2190
2191/*
2192 * Commit the records to the pool.
2193 */
2194static int
2195receive_process_record(struct receive_writer_arg *rwa,
2196    struct receive_record_arg *rrd)
2197{
2198	int err;
2199
2200	/* Processing in order, therefore bytes_read should be increasing. */
2201	ASSERT3U(rrd->bytes_read, >=, rwa->bytes_read);
2202	rwa->bytes_read = rrd->bytes_read;
2203
2204	switch (rrd->header.drr_type) {
2205	case DRR_OBJECT:
2206	{
2207		struct drr_object *drro = &rrd->header.drr_u.drr_object;
2208		err = receive_object(rwa, drro, rrd->payload);
2209		kmem_free(rrd->payload, rrd->payload_size);
2210		rrd->payload = NULL;
2211		return (err);
2212	}
2213	case DRR_FREEOBJECTS:
2214	{
2215		struct drr_freeobjects *drrfo =
2216		    &rrd->header.drr_u.drr_freeobjects;
2217		return (receive_freeobjects(rwa, drrfo));
2218	}
2219	case DRR_WRITE:
2220	{
2221		struct drr_write *drrw = &rrd->header.drr_u.drr_write;
2222		err = receive_write(rwa, drrw, rrd->arc_buf);
2223		/* if receive_write() is successful, it consumes the arc_buf */
2224		if (err != 0)
2225			dmu_return_arcbuf(rrd->arc_buf);
2226		rrd->arc_buf = NULL;
2227		rrd->payload = NULL;
2228		return (err);
2229	}
2230	case DRR_WRITE_BYREF:
2231	{
2232		struct drr_write_byref *drrwbr =
2233		    &rrd->header.drr_u.drr_write_byref;
2234		return (receive_write_byref(rwa, drrwbr));
2235	}
2236	case DRR_WRITE_EMBEDDED:
2237	{
2238		struct drr_write_embedded *drrwe =
2239		    &rrd->header.drr_u.drr_write_embedded;
2240		err = receive_write_embedded(rwa, drrwe, rrd->payload);
2241		kmem_free(rrd->payload, rrd->payload_size);
2242		rrd->payload = NULL;
2243		return (err);
2244	}
2245	case DRR_FREE:
2246	{
2247		struct drr_free *drrf = &rrd->header.drr_u.drr_free;
2248		return (receive_free(rwa, drrf));
2249	}
2250	case DRR_SPILL:
2251	{
2252		struct drr_spill *drrs = &rrd->header.drr_u.drr_spill;
2253		err = receive_spill(rwa, drrs, rrd->arc_buf);
2254		/* if receive_spill() is successful, it consumes the arc_buf */
2255		if (err != 0)
2256			dmu_return_arcbuf(rrd->arc_buf);
2257		rrd->arc_buf = NULL;
2258		rrd->payload = NULL;
2259		return (err);
2260	}
2261	case DRR_OBJECT_RANGE:
2262	{
2263		struct drr_object_range *drror =
2264		    &rrd->header.drr_u.drr_object_range;
2265		return (receive_object_range(rwa, drror));
2266	}
2267	default:
2268		return (SET_ERROR(EINVAL));
2269	}
2270}
2271
2272/*
2273 * dmu_recv_stream's worker thread; pull records off the queue, and then call
2274 * receive_process_record  When we're done, signal the main thread and exit.
2275 */
2276static void
2277receive_writer_thread(void *arg)
2278{
2279	struct receive_writer_arg *rwa = arg;
2280	struct receive_record_arg *rrd;
2281	for (rrd = bqueue_dequeue(&rwa->q); !rrd->eos_marker;
2282	    rrd = bqueue_dequeue(&rwa->q)) {
2283		/*
2284		 * If there's an error, the main thread will stop putting things
2285		 * on the queue, but we need to clear everything in it before we
2286		 * can exit.
2287		 */
2288		if (rwa->err == 0) {
2289			rwa->err = receive_process_record(rwa, rrd);
2290		} else if (rrd->arc_buf != NULL) {
2291			dmu_return_arcbuf(rrd->arc_buf);
2292			rrd->arc_buf = NULL;
2293			rrd->payload = NULL;
2294		} else if (rrd->payload != NULL) {
2295			kmem_free(rrd->payload, rrd->payload_size);
2296			rrd->payload = NULL;
2297		}
2298		kmem_free(rrd, sizeof (*rrd));
2299	}
2300	kmem_free(rrd, sizeof (*rrd));
2301	mutex_enter(&rwa->mutex);
2302	rwa->done = B_TRUE;
2303	cv_signal(&rwa->cv);
2304	mutex_exit(&rwa->mutex);
2305	thread_exit();
2306}
2307
2308static int
2309resume_check(struct receive_arg *ra, nvlist_t *begin_nvl)
2310{
2311	uint64_t val;
2312	objset_t *mos = dmu_objset_pool(ra->os)->dp_meta_objset;
2313	uint64_t dsobj = dmu_objset_id(ra->os);
2314	uint64_t resume_obj, resume_off;
2315
2316	if (nvlist_lookup_uint64(begin_nvl,
2317	    "resume_object", &resume_obj) != 0 ||
2318	    nvlist_lookup_uint64(begin_nvl,
2319	    "resume_offset", &resume_off) != 0) {
2320		return (SET_ERROR(EINVAL));
2321	}
2322	VERIFY0(zap_lookup(mos, dsobj,
2323	    DS_FIELD_RESUME_OBJECT, sizeof (val), 1, &val));
2324	if (resume_obj != val)
2325		return (SET_ERROR(EINVAL));
2326	VERIFY0(zap_lookup(mos, dsobj,
2327	    DS_FIELD_RESUME_OFFSET, sizeof (val), 1, &val));
2328	if (resume_off != val)
2329		return (SET_ERROR(EINVAL));
2330
2331	return (0);
2332}
2333
2334/*
2335 * Read in the stream's records, one by one, and apply them to the pool.  There
2336 * are two threads involved; the thread that calls this function will spin up a
2337 * worker thread, read the records off the stream one by one, and issue
2338 * prefetches for any necessary indirect blocks.  It will then push the records
2339 * onto an internal blocking queue.  The worker thread will pull the records off
2340 * the queue, and actually write the data into the DMU.  This way, the worker
2341 * thread doesn't have to wait for reads to complete, since everything it needs
2342 * (the indirect blocks) will be prefetched.
2343 *
2344 * NB: callers *must* call dmu_recv_end() if this succeeds.
2345 */
2346int
2347dmu_recv_stream(dmu_recv_cookie_t *drc, vnode_t *vp, offset_t *voffp,
2348    int cleanup_fd, uint64_t *action_handlep)
2349{
2350	int err = 0;
2351	struct receive_arg ra = { 0 };
2352	struct receive_writer_arg rwa = { 0 };
2353	int featureflags;
2354	nvlist_t *begin_nvl = NULL;
2355
2356	ra.byteswap = drc->drc_byteswap;
2357	ra.raw = drc->drc_raw;
2358	ra.cksum = drc->drc_cksum;
2359	ra.vp = vp;
2360	ra.voff = *voffp;
2361
2362	if (dsl_dataset_is_zapified(drc->drc_ds)) {
2363		(void) zap_lookup(drc->drc_ds->ds_dir->dd_pool->dp_meta_objset,
2364		    drc->drc_ds->ds_object, DS_FIELD_RESUME_BYTES,
2365		    sizeof (ra.bytes_read), 1, &ra.bytes_read);
2366	}
2367
2368	objlist_create(&ra.ignore_objlist);
2369
2370	/* these were verified in dmu_recv_begin */
2371	ASSERT3U(DMU_GET_STREAM_HDRTYPE(drc->drc_drrb->drr_versioninfo), ==,
2372	    DMU_SUBSTREAM);
2373	ASSERT3U(drc->drc_drrb->drr_type, <, DMU_OST_NUMTYPES);
2374
2375	/*
2376	 * Open the objset we are modifying.
2377	 */
2378	VERIFY0(dmu_objset_from_ds(drc->drc_ds, &ra.os));
2379
2380	ASSERT(dsl_dataset_phys(drc->drc_ds)->ds_flags & DS_FLAG_INCONSISTENT);
2381
2382	featureflags = DMU_GET_FEATUREFLAGS(drc->drc_drrb->drr_versioninfo);
2383	ra.featureflags = featureflags;
2384
2385	ASSERT0(ra.os->os_encrypted &&
2386	    (featureflags & DMU_BACKUP_FEATURE_EMBED_DATA));
2387
2388	/* if this stream is dedup'ed, set up the avl tree for guid mapping */
2389	if (featureflags & DMU_BACKUP_FEATURE_DEDUP) {
2390		minor_t minor;
2391
2392		if (cleanup_fd == -1) {
2393			err = SET_ERROR(EBADF);
2394			goto out;
2395		}
2396		err = zfs_onexit_fd_hold(cleanup_fd, &minor);
2397		if (err != 0) {
2398			cleanup_fd = -1;
2399			goto out;
2400		}
2401
2402		if (*action_handlep == 0) {
2403			rwa.guid_to_ds_map =
2404			    kmem_alloc(sizeof (avl_tree_t), KM_SLEEP);
2405			avl_create(rwa.guid_to_ds_map, guid_compare,
2406			    sizeof (guid_map_entry_t),
2407			    offsetof(guid_map_entry_t, avlnode));
2408			err = zfs_onexit_add_cb(minor,
2409			    free_guid_map_onexit, rwa.guid_to_ds_map,
2410			    action_handlep);
2411			if (err != 0)
2412				goto out;
2413		} else {
2414			err = zfs_onexit_cb_data(minor, *action_handlep,
2415			    (void **)&rwa.guid_to_ds_map);
2416			if (err != 0)
2417				goto out;
2418		}
2419
2420		drc->drc_guid_to_ds_map = rwa.guid_to_ds_map;
2421	}
2422
2423	uint32_t payloadlen = drc->drc_drr_begin->drr_payloadlen;
2424	void *payload = NULL;
2425	if (payloadlen != 0)
2426		payload = kmem_alloc(payloadlen, KM_SLEEP);
2427
2428	err = receive_read_payload_and_next_header(&ra, payloadlen, payload);
2429	if (err != 0) {
2430		if (payloadlen != 0)
2431			kmem_free(payload, payloadlen);
2432		goto out;
2433	}
2434	if (payloadlen != 0) {
2435		err = nvlist_unpack(payload, payloadlen, &begin_nvl, KM_SLEEP);
2436		kmem_free(payload, payloadlen);
2437		if (err != 0)
2438			goto out;
2439	}
2440
2441	/* handle DSL encryption key payload */
2442	if (featureflags & DMU_BACKUP_FEATURE_RAW) {
2443		nvlist_t *keynvl = NULL;
2444
2445		ASSERT(ra.os->os_encrypted);
2446		ASSERT(drc->drc_raw);
2447
2448		err = nvlist_lookup_nvlist(begin_nvl, "crypt_keydata", &keynvl);
2449		if (err != 0)
2450			goto out;
2451
2452		/*
2453		 * If this is a new dataset we set the key immediately.
2454		 * Otherwise we don't want to change the key until we
2455		 * are sure the rest of the receive succeeded so we stash
2456		 * the keynvl away until then.
2457		 */
2458		err = dsl_crypto_recv_raw(spa_name(ra.os->os_spa),
2459		    drc->drc_ds->ds_object, drc->drc_fromsnapobj,
2460		    drc->drc_drrb->drr_type, keynvl, drc->drc_newfs);
2461		if (err != 0)
2462			goto out;
2463
2464		/* see comment in dmu_recv_end_sync() */
2465		drc->drc_ivset_guid = 0;
2466		(void) nvlist_lookup_uint64(keynvl, "to_ivset_guid",
2467		    &drc->drc_ivset_guid);
2468
2469		if (!drc->drc_newfs)
2470			drc->drc_keynvl = fnvlist_dup(keynvl);
2471	}
2472
2473	if (featureflags & DMU_BACKUP_FEATURE_RESUMING) {
2474		err = resume_check(&ra, begin_nvl);
2475		if (err != 0)
2476			goto out;
2477	}
2478
2479	(void) bqueue_init(&rwa.q,
2480	    MAX(zfs_recv_queue_length, 2 * zfs_max_recordsize),
2481	    offsetof(struct receive_record_arg, node));
2482	cv_init(&rwa.cv, NULL, CV_DEFAULT, NULL);
2483	mutex_init(&rwa.mutex, NULL, MUTEX_DEFAULT, NULL);
2484	rwa.os = ra.os;
2485	rwa.byteswap = drc->drc_byteswap;
2486	rwa.resumable = drc->drc_resumable;
2487	rwa.raw = drc->drc_raw;
2488	rwa.spill = drc->drc_spill;
2489	rwa.os->os_raw_receive = drc->drc_raw;
2490
2491	(void) thread_create(NULL, 0, receive_writer_thread, &rwa, 0, curproc,
2492	    TS_RUN, minclsyspri);
2493	/*
2494	 * We're reading rwa.err without locks, which is safe since we are the
2495	 * only reader, and the worker thread is the only writer.  It's ok if we
2496	 * miss a write for an iteration or two of the loop, since the writer
2497	 * thread will keep freeing records we send it until we send it an eos
2498	 * marker.
2499	 *
2500	 * We can leave this loop in 3 ways:  First, if rwa.err is
2501	 * non-zero.  In that case, the writer thread will free the rrd we just
2502	 * pushed.  Second, if  we're interrupted; in that case, either it's the
2503	 * first loop and ra.rrd was never allocated, or it's later, and ra.rrd
2504	 * has been handed off to the writer thread who will free it.  Finally,
2505	 * if receive_read_record fails or we're at the end of the stream, then
2506	 * we free ra.rrd and exit.
2507	 */
2508	while (rwa.err == 0) {
2509		if (issig(JUSTLOOKING) && issig(FORREAL)) {
2510			err = SET_ERROR(EINTR);
2511			break;
2512		}
2513
2514		ASSERT3P(ra.rrd, ==, NULL);
2515		ra.rrd = ra.next_rrd;
2516		ra.next_rrd = NULL;
2517		/* Allocates and loads header into ra.next_rrd */
2518		err = receive_read_record(&ra);
2519
2520		if (ra.rrd->header.drr_type == DRR_END || err != 0) {
2521			kmem_free(ra.rrd, sizeof (*ra.rrd));
2522			ra.rrd = NULL;
2523			break;
2524		}
2525
2526		bqueue_enqueue(&rwa.q, ra.rrd,
2527		    sizeof (struct receive_record_arg) + ra.rrd->payload_size);
2528		ra.rrd = NULL;
2529	}
2530	ASSERT3P(ra.rrd, ==, NULL);
2531	ra.rrd = kmem_zalloc(sizeof (*ra.rrd), KM_SLEEP);
2532	ra.rrd->eos_marker = B_TRUE;
2533	bqueue_enqueue(&rwa.q, ra.rrd, 1);
2534
2535	mutex_enter(&rwa.mutex);
2536	while (!rwa.done) {
2537		cv_wait(&rwa.cv, &rwa.mutex);
2538	}
2539	mutex_exit(&rwa.mutex);
2540
2541	/*
2542	 * If we are receiving a full stream as a clone, all object IDs which
2543	 * are greater than the maximum ID referenced in the stream are
2544	 * by definition unused and must be freed. Note that it's possible that
2545	 * we've resumed this send and the first record we received was the END
2546	 * record. In that case, max_object would be 0, but we shouldn't start
2547	 * freeing all objects from there; instead we should start from the
2548	 * resumeobj.
2549	 */
2550	if (drc->drc_clone && drc->drc_drrb->drr_fromguid == 0) {
2551		uint64_t obj;
2552		if (nvlist_lookup_uint64(begin_nvl, "resume_object", &obj) != 0)
2553			obj = 0;
2554		if (rwa.max_object > obj)
2555			obj = rwa.max_object;
2556		obj++;
2557		int free_err = 0;
2558		int next_err = 0;
2559
2560		while (next_err == 0) {
2561			free_err = dmu_free_long_object(rwa.os, obj);
2562			if (free_err != 0 && free_err != ENOENT)
2563				break;
2564
2565			next_err = dmu_object_next(rwa.os, &obj, FALSE, 0);
2566		}
2567
2568		if (err == 0) {
2569			if (free_err != 0 && free_err != ENOENT)
2570				err = free_err;
2571			else if (next_err != ESRCH)
2572				err = next_err;
2573		}
2574	}
2575
2576	cv_destroy(&rwa.cv);
2577	mutex_destroy(&rwa.mutex);
2578	bqueue_destroy(&rwa.q);
2579	if (err == 0)
2580		err = rwa.err;
2581
2582out:
2583	/*
2584	 * If we hit an error before we started the receive_writer_thread
2585	 * we need to clean up the next_rrd we create by processing the
2586	 * DRR_BEGIN record.
2587	 */
2588	if (ra.next_rrd != NULL)
2589		kmem_free(ra.next_rrd, sizeof (*ra.next_rrd));
2590
2591	nvlist_free(begin_nvl);
2592	if ((featureflags & DMU_BACKUP_FEATURE_DEDUP) && (cleanup_fd != -1))
2593		zfs_onexit_fd_rele(cleanup_fd);
2594
2595	if (err != 0) {
2596		/*
2597		 * Clean up references. If receive is not resumable,
2598		 * destroy what we created, so we don't leave it in
2599		 * the inconsistent state.
2600		 */
2601		dmu_recv_cleanup_ds(drc);
2602		nvlist_free(drc->drc_keynvl);
2603	}
2604
2605	*voffp = ra.voff;
2606	objlist_destroy(&ra.ignore_objlist);
2607	return (err);
2608}
2609
2610static int
2611dmu_recv_end_check(void *arg, dmu_tx_t *tx)
2612{
2613	dmu_recv_cookie_t *drc = arg;
2614	dsl_pool_t *dp = dmu_tx_pool(tx);
2615	int error;
2616
2617	ASSERT3P(drc->drc_ds->ds_owner, ==, dmu_recv_tag);
2618
2619	if (!drc->drc_newfs) {
2620		dsl_dataset_t *origin_head;
2621
2622		error = dsl_dataset_hold(dp, drc->drc_tofs, FTAG, &origin_head);
2623		if (error != 0)
2624			return (error);
2625		if (drc->drc_force) {
2626			/*
2627			 * We will destroy any snapshots in tofs (i.e. before
2628			 * origin_head) that are after the origin (which is
2629			 * the snap before drc_ds, because drc_ds can not
2630			 * have any snaps of its own).
2631			 */
2632			uint64_t obj;
2633
2634			obj = dsl_dataset_phys(origin_head)->ds_prev_snap_obj;
2635			while (obj !=
2636			    dsl_dataset_phys(drc->drc_ds)->ds_prev_snap_obj) {
2637				dsl_dataset_t *snap;
2638				error = dsl_dataset_hold_obj(dp, obj, FTAG,
2639				    &snap);
2640				if (error != 0)
2641					break;
2642				if (snap->ds_dir != origin_head->ds_dir)
2643					error = SET_ERROR(EINVAL);
2644				if (error == 0)  {
2645					error = dsl_destroy_snapshot_check_impl(
2646					    snap, B_FALSE);
2647				}
2648				obj = dsl_dataset_phys(snap)->ds_prev_snap_obj;
2649				dsl_dataset_rele(snap, FTAG);
2650				if (error != 0)
2651					break;
2652			}
2653			if (error != 0) {
2654				dsl_dataset_rele(origin_head, FTAG);
2655				return (error);
2656			}
2657		}
2658		if (drc->drc_keynvl != NULL) {
2659			error = dsl_crypto_recv_raw_key_check(drc->drc_ds,
2660			    drc->drc_keynvl, tx);
2661			if (error != 0) {
2662				dsl_dataset_rele(origin_head, FTAG);
2663				return (error);
2664			}
2665		}
2666
2667		error = dsl_dataset_clone_swap_check_impl(drc->drc_ds,
2668		    origin_head, drc->drc_force, drc->drc_owner, tx);
2669		if (error != 0) {
2670			dsl_dataset_rele(origin_head, FTAG);
2671			return (error);
2672		}
2673		error = dsl_dataset_snapshot_check_impl(origin_head,
2674		    drc->drc_tosnap, tx, B_TRUE, 1, drc->drc_cred);
2675		dsl_dataset_rele(origin_head, FTAG);
2676		if (error != 0)
2677			return (error);
2678
2679		error = dsl_destroy_head_check_impl(drc->drc_ds, 1);
2680	} else {
2681		error = dsl_dataset_snapshot_check_impl(drc->drc_ds,
2682		    drc->drc_tosnap, tx, B_TRUE, 1, drc->drc_cred);
2683	}
2684	return (error);
2685}
2686
2687static void
2688dmu_recv_end_sync(void *arg, dmu_tx_t *tx)
2689{
2690	dmu_recv_cookie_t *drc = arg;
2691	dsl_pool_t *dp = dmu_tx_pool(tx);
2692	boolean_t encrypted = drc->drc_ds->ds_dir->dd_crypto_obj != 0;
2693
2694	spa_history_log_internal_ds(drc->drc_ds, "finish receiving",
2695	    tx, "snap=%s", drc->drc_tosnap);
2696	drc->drc_ds->ds_objset->os_raw_receive = B_FALSE;
2697
2698	if (!drc->drc_newfs) {
2699		dsl_dataset_t *origin_head;
2700
2701		VERIFY0(dsl_dataset_hold(dp, drc->drc_tofs, FTAG,
2702		    &origin_head));
2703
2704		if (drc->drc_force) {
2705			/*
2706			 * Destroy any snapshots of drc_tofs (origin_head)
2707			 * after the origin (the snap before drc_ds).
2708			 */
2709			uint64_t obj;
2710
2711			obj = dsl_dataset_phys(origin_head)->ds_prev_snap_obj;
2712			while (obj !=
2713			    dsl_dataset_phys(drc->drc_ds)->ds_prev_snap_obj) {
2714				dsl_dataset_t *snap;
2715				VERIFY0(dsl_dataset_hold_obj(dp, obj, FTAG,
2716				    &snap));
2717				ASSERT3P(snap->ds_dir, ==, origin_head->ds_dir);
2718				obj = dsl_dataset_phys(snap)->ds_prev_snap_obj;
2719				dsl_destroy_snapshot_sync_impl(snap,
2720				    B_FALSE, tx);
2721				dsl_dataset_rele(snap, FTAG);
2722			}
2723		}
2724		if (drc->drc_keynvl != NULL) {
2725			dsl_crypto_recv_raw_key_sync(drc->drc_ds,
2726			    drc->drc_keynvl, tx);
2727			nvlist_free(drc->drc_keynvl);
2728			drc->drc_keynvl = NULL;
2729		}
2730
2731		VERIFY3P(drc->drc_ds->ds_prev, ==, origin_head->ds_prev);
2732
2733		dsl_dataset_clone_swap_sync_impl(drc->drc_ds,
2734		    origin_head, tx);
2735		dsl_dataset_snapshot_sync_impl(origin_head,
2736		    drc->drc_tosnap, tx);
2737
2738		/* set snapshot's creation time and guid */
2739		dmu_buf_will_dirty(origin_head->ds_prev->ds_dbuf, tx);
2740		dsl_dataset_phys(origin_head->ds_prev)->ds_creation_time =
2741		    drc->drc_drrb->drr_creation_time;
2742		dsl_dataset_phys(origin_head->ds_prev)->ds_guid =
2743		    drc->drc_drrb->drr_toguid;
2744		dsl_dataset_phys(origin_head->ds_prev)->ds_flags &=
2745		    ~DS_FLAG_INCONSISTENT;
2746
2747		dmu_buf_will_dirty(origin_head->ds_dbuf, tx);
2748		dsl_dataset_phys(origin_head)->ds_flags &=
2749		    ~DS_FLAG_INCONSISTENT;
2750
2751		drc->drc_newsnapobj =
2752		    dsl_dataset_phys(origin_head)->ds_prev_snap_obj;
2753
2754		dsl_dataset_rele(origin_head, FTAG);
2755		dsl_destroy_head_sync_impl(drc->drc_ds, tx);
2756
2757		if (drc->drc_owner != NULL)
2758			VERIFY3P(origin_head->ds_owner, ==, drc->drc_owner);
2759	} else {
2760		dsl_dataset_t *ds = drc->drc_ds;
2761
2762		dsl_dataset_snapshot_sync_impl(ds, drc->drc_tosnap, tx);
2763
2764		/* set snapshot's creation time and guid */
2765		dmu_buf_will_dirty(ds->ds_prev->ds_dbuf, tx);
2766		dsl_dataset_phys(ds->ds_prev)->ds_creation_time =
2767		    drc->drc_drrb->drr_creation_time;
2768		dsl_dataset_phys(ds->ds_prev)->ds_guid =
2769		    drc->drc_drrb->drr_toguid;
2770		dsl_dataset_phys(ds->ds_prev)->ds_flags &=
2771		    ~DS_FLAG_INCONSISTENT;
2772
2773		dmu_buf_will_dirty(ds->ds_dbuf, tx);
2774		dsl_dataset_phys(ds)->ds_flags &= ~DS_FLAG_INCONSISTENT;
2775		if (dsl_dataset_has_resume_receive_state(ds)) {
2776			(void) zap_remove(dp->dp_meta_objset, ds->ds_object,
2777			    DS_FIELD_RESUME_FROMGUID, tx);
2778			(void) zap_remove(dp->dp_meta_objset, ds->ds_object,
2779			    DS_FIELD_RESUME_OBJECT, tx);
2780			(void) zap_remove(dp->dp_meta_objset, ds->ds_object,
2781			    DS_FIELD_RESUME_OFFSET, tx);
2782			(void) zap_remove(dp->dp_meta_objset, ds->ds_object,
2783			    DS_FIELD_RESUME_BYTES, tx);
2784			(void) zap_remove(dp->dp_meta_objset, ds->ds_object,
2785			    DS_FIELD_RESUME_TOGUID, tx);
2786			(void) zap_remove(dp->dp_meta_objset, ds->ds_object,
2787			    DS_FIELD_RESUME_TONAME, tx);
2788		}
2789		drc->drc_newsnapobj =
2790		    dsl_dataset_phys(drc->drc_ds)->ds_prev_snap_obj;
2791	}
2792
2793	/*
2794	 * If this is a raw receive, the crypt_keydata nvlist will include
2795	 * a to_ivset_guid for us to set on the new snapshot. This value
2796	 * will override the value generated by the snapshot code. However,
2797	 * this value may not be present, because older implementations of
2798	 * the raw send code did not include this value, and we are still
2799	 * allowed to receive them if the zfs_disable_ivset_guid_check
2800	 * tunable is set, in which case we will leave the newly-generated
2801	 * value.
2802	 */
2803	if (drc->drc_raw && drc->drc_ivset_guid != 0) {
2804		dmu_object_zapify(dp->dp_meta_objset, drc->drc_newsnapobj,
2805		    DMU_OT_DSL_DATASET, tx);
2806		VERIFY0(zap_update(dp->dp_meta_objset, drc->drc_newsnapobj,
2807		    DS_FIELD_IVSET_GUID, sizeof (uint64_t), 1,
2808		    &drc->drc_ivset_guid, tx));
2809	}
2810
2811	/*
2812	 * Release the hold from dmu_recv_begin.  This must be done before
2813	 * we return to open context, so that when we free the dataset's dnode
2814	 * we can evict its bonus buffer. Since the dataset may be destroyed
2815	 * at this point (and therefore won't have a valid pointer to the spa)
2816	 * we release the key mapping manually here while we do have a valid
2817	 * pointer, if it exists.
2818	 */
2819	if (!drc->drc_raw && encrypted) {
2820		(void) spa_keystore_remove_mapping(dmu_tx_pool(tx)->dp_spa,
2821		    drc->drc_ds->ds_object, drc->drc_ds);
2822	}
2823	dsl_dataset_disown(drc->drc_ds, 0, dmu_recv_tag);
2824	drc->drc_ds = NULL;
2825}
2826
2827static int
2828add_ds_to_guidmap(const char *name, avl_tree_t *guid_map, uint64_t snapobj,
2829    boolean_t raw)
2830{
2831	dsl_pool_t *dp;
2832	dsl_dataset_t *snapds;
2833	guid_map_entry_t *gmep;
2834	objset_t *os;
2835	ds_hold_flags_t dsflags = (raw) ? 0 : DS_HOLD_FLAG_DECRYPT;
2836	int err;
2837
2838	ASSERT(guid_map != NULL);
2839
2840	err = dsl_pool_hold(name, FTAG, &dp);
2841	if (err != 0)
2842		return (err);
2843	gmep = kmem_alloc(sizeof (*gmep), KM_SLEEP);
2844	err = dsl_dataset_own_obj(dp, snapobj, dsflags, gmep, &snapds);
2845	if (err == 0) {
2846		/*
2847		 * If this is a deduplicated raw send stream, we need
2848		 * to make sure that we can still read raw blocks from
2849		 * earlier datasets in the stream, so we set the
2850		 * os_raw_receive flag now.
2851		 */
2852		if (raw) {
2853			err = dmu_objset_from_ds(snapds, &os);
2854			if (err != 0) {
2855				dsl_dataset_disown(snapds, dsflags, FTAG);
2856				dsl_pool_rele(dp, FTAG);
2857				kmem_free(gmep, sizeof (*gmep));
2858				return (err);
2859			}
2860			os->os_raw_receive = B_TRUE;
2861		}
2862
2863		gmep->raw = raw;
2864		gmep->guid = dsl_dataset_phys(snapds)->ds_guid;
2865		gmep->gme_ds = snapds;
2866		avl_add(guid_map, gmep);
2867	} else {
2868		kmem_free(gmep, sizeof (*gmep));
2869	}
2870
2871	dsl_pool_rele(dp, FTAG);
2872	return (err);
2873}
2874
2875static int dmu_recv_end_modified_blocks = 3;
2876
2877static int
2878dmu_recv_existing_end(dmu_recv_cookie_t *drc)
2879{
2880#ifdef _KERNEL
2881	/*
2882	 * We will be destroying the ds; make sure its origin is unmounted if
2883	 * necessary.
2884	 */
2885	char name[ZFS_MAX_DATASET_NAME_LEN];
2886	dsl_dataset_name(drc->drc_ds, name);
2887	zfs_destroy_unmount_origin(name);
2888#endif
2889
2890	return (dsl_sync_task(drc->drc_tofs,
2891	    dmu_recv_end_check, dmu_recv_end_sync, drc,
2892	    dmu_recv_end_modified_blocks, ZFS_SPACE_CHECK_NORMAL));
2893}
2894
2895static int
2896dmu_recv_new_end(dmu_recv_cookie_t *drc)
2897{
2898	return (dsl_sync_task(drc->drc_tofs,
2899	    dmu_recv_end_check, dmu_recv_end_sync, drc,
2900	    dmu_recv_end_modified_blocks, ZFS_SPACE_CHECK_NORMAL));
2901}
2902
2903int
2904dmu_recv_end(dmu_recv_cookie_t *drc, void *owner)
2905{
2906	int error;
2907
2908	drc->drc_owner = owner;
2909
2910	if (drc->drc_newfs)
2911		error = dmu_recv_new_end(drc);
2912	else
2913		error = dmu_recv_existing_end(drc);
2914
2915	if (error != 0) {
2916		dmu_recv_cleanup_ds(drc);
2917		nvlist_free(drc->drc_keynvl);
2918	} else if (drc->drc_guid_to_ds_map != NULL) {
2919		(void) add_ds_to_guidmap(drc->drc_tofs, drc->drc_guid_to_ds_map,
2920		    drc->drc_newsnapobj, drc->drc_raw);
2921	}
2922	return (error);
2923}
2924
2925/*
2926 * Return TRUE if this objset is currently being received into.
2927 */
2928boolean_t
2929dmu_objset_is_receiving(objset_t *os)
2930{
2931	return (os->os_dsl_dataset != NULL &&
2932	    os->os_dsl_dataset->ds_owner == dmu_recv_tag);
2933}
2934