xref: /freebsd-11-stable/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_objset.c (revision d85081ebc2fa309553783e2298f255fb53f66d1e)
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 /*
23  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
24  * Copyright (c) 2012, 2017 by Delphix. All rights reserved.
25  * Copyright (c) 2013 by Saso Kiselkov. All rights reserved.
26  * Copyright (c) 2013, Joyent, Inc. All rights reserved.
27  * Copyright (c) 2014 Spectra Logic Corporation, All rights reserved.
28  * Copyright (c) 2015, STRATO AG, Inc. All rights reserved.
29  * Copyright (c) 2014 Integros [integros.com]
30  * Copyright 2017 Nexenta Systems, Inc.
31  * Copyright (c) 2018, loli10K <ezomori.nozomu@gmail.com>. All rights reserved.
32  */
33 
34 /* Portions Copyright 2010 Robert Milkowski */
35 
36 #include <sys/cred.h>
37 #include <sys/zfs_context.h>
38 #include <sys/dmu_objset.h>
39 #include <sys/dsl_dir.h>
40 #include <sys/dsl_dataset.h>
41 #include <sys/dsl_prop.h>
42 #include <sys/dsl_pool.h>
43 #include <sys/dsl_synctask.h>
44 #include <sys/dsl_deleg.h>
45 #include <sys/dnode.h>
46 #include <sys/dbuf.h>
47 #include <sys/zvol.h>
48 #include <sys/dmu_tx.h>
49 #include <sys/zap.h>
50 #include <sys/zil.h>
51 #include <sys/dmu_impl.h>
52 #include <sys/zfs_ioctl.h>
53 #include <sys/sa.h>
54 #include <sys/zfs_onexit.h>
55 #include <sys/dsl_destroy.h>
56 #include <sys/vdev.h>
57 #include <sys/zfeature.h>
58 #include "zfs_namecheck.h"
59 
60 /*
61  * Needed to close a window in dnode_move() that allows the objset to be freed
62  * before it can be safely accessed.
63  */
64 krwlock_t os_lock;
65 
66 /*
67  * Tunable to overwrite the maximum number of threads for the parallization
68  * of dmu_objset_find_dp, needed to speed up the import of pools with many
69  * datasets.
70  * Default is 4 times the number of leaf vdevs.
71  */
72 int dmu_find_threads = 0;
73 
74 /*
75  * Backfill lower metadnode objects after this many have been freed.
76  * Backfilling negatively impacts object creation rates, so only do it
77  * if there are enough holes to fill.
78  */
79 int dmu_rescan_dnode_threshold = 131072;
80 
81 static void dmu_objset_find_dp_cb(void *arg);
82 
83 void
dmu_objset_init(void)84 dmu_objset_init(void)
85 {
86 	rw_init(&os_lock, NULL, RW_DEFAULT, NULL);
87 }
88 
89 void
dmu_objset_fini(void)90 dmu_objset_fini(void)
91 {
92 	rw_destroy(&os_lock);
93 }
94 
95 spa_t *
dmu_objset_spa(objset_t * os)96 dmu_objset_spa(objset_t *os)
97 {
98 	return (os->os_spa);
99 }
100 
101 zilog_t *
dmu_objset_zil(objset_t * os)102 dmu_objset_zil(objset_t *os)
103 {
104 	return (os->os_zil);
105 }
106 
107 dsl_pool_t *
dmu_objset_pool(objset_t * os)108 dmu_objset_pool(objset_t *os)
109 {
110 	dsl_dataset_t *ds;
111 
112 	if ((ds = os->os_dsl_dataset) != NULL && ds->ds_dir)
113 		return (ds->ds_dir->dd_pool);
114 	else
115 		return (spa_get_dsl(os->os_spa));
116 }
117 
118 dsl_dataset_t *
dmu_objset_ds(objset_t * os)119 dmu_objset_ds(objset_t *os)
120 {
121 	return (os->os_dsl_dataset);
122 }
123 
124 dmu_objset_type_t
dmu_objset_type(objset_t * os)125 dmu_objset_type(objset_t *os)
126 {
127 	return (os->os_phys->os_type);
128 }
129 
130 void
dmu_objset_name(objset_t * os,char * buf)131 dmu_objset_name(objset_t *os, char *buf)
132 {
133 	dsl_dataset_name(os->os_dsl_dataset, buf);
134 }
135 
136 uint64_t
dmu_objset_id(objset_t * os)137 dmu_objset_id(objset_t *os)
138 {
139 	dsl_dataset_t *ds = os->os_dsl_dataset;
140 
141 	return (ds ? ds->ds_object : 0);
142 }
143 
144 zfs_sync_type_t
dmu_objset_syncprop(objset_t * os)145 dmu_objset_syncprop(objset_t *os)
146 {
147 	return (os->os_sync);
148 }
149 
150 zfs_logbias_op_t
dmu_objset_logbias(objset_t * os)151 dmu_objset_logbias(objset_t *os)
152 {
153 	return (os->os_logbias);
154 }
155 
156 static void
checksum_changed_cb(void * arg,uint64_t newval)157 checksum_changed_cb(void *arg, uint64_t newval)
158 {
159 	objset_t *os = arg;
160 
161 	/*
162 	 * Inheritance should have been done by now.
163 	 */
164 	ASSERT(newval != ZIO_CHECKSUM_INHERIT);
165 
166 	os->os_checksum = zio_checksum_select(newval, ZIO_CHECKSUM_ON_VALUE);
167 }
168 
169 static void
compression_changed_cb(void * arg,uint64_t newval)170 compression_changed_cb(void *arg, uint64_t newval)
171 {
172 	objset_t *os = arg;
173 
174 	/*
175 	 * Inheritance and range checking should have been done by now.
176 	 */
177 	ASSERT(newval != ZIO_COMPRESS_INHERIT);
178 
179 	os->os_compress = zio_compress_select(os->os_spa, newval,
180 	    ZIO_COMPRESS_ON);
181 }
182 
183 static void
copies_changed_cb(void * arg,uint64_t newval)184 copies_changed_cb(void *arg, uint64_t newval)
185 {
186 	objset_t *os = arg;
187 
188 	/*
189 	 * Inheritance and range checking should have been done by now.
190 	 */
191 	ASSERT(newval > 0);
192 	ASSERT(newval <= spa_max_replication(os->os_spa));
193 
194 	os->os_copies = newval;
195 }
196 
197 static void
dedup_changed_cb(void * arg,uint64_t newval)198 dedup_changed_cb(void *arg, uint64_t newval)
199 {
200 	objset_t *os = arg;
201 	spa_t *spa = os->os_spa;
202 	enum zio_checksum checksum;
203 
204 	/*
205 	 * Inheritance should have been done by now.
206 	 */
207 	ASSERT(newval != ZIO_CHECKSUM_INHERIT);
208 
209 	checksum = zio_checksum_dedup_select(spa, newval, ZIO_CHECKSUM_OFF);
210 
211 	os->os_dedup_checksum = checksum & ZIO_CHECKSUM_MASK;
212 	os->os_dedup_verify = !!(checksum & ZIO_CHECKSUM_VERIFY);
213 }
214 
215 static void
primary_cache_changed_cb(void * arg,uint64_t newval)216 primary_cache_changed_cb(void *arg, uint64_t newval)
217 {
218 	objset_t *os = arg;
219 
220 	/*
221 	 * Inheritance and range checking should have been done by now.
222 	 */
223 	ASSERT(newval == ZFS_CACHE_ALL || newval == ZFS_CACHE_NONE ||
224 	    newval == ZFS_CACHE_METADATA);
225 
226 	os->os_primary_cache = newval;
227 }
228 
229 static void
secondary_cache_changed_cb(void * arg,uint64_t newval)230 secondary_cache_changed_cb(void *arg, uint64_t newval)
231 {
232 	objset_t *os = arg;
233 
234 	/*
235 	 * Inheritance and range checking should have been done by now.
236 	 */
237 	ASSERT(newval == ZFS_CACHE_ALL || newval == ZFS_CACHE_NONE ||
238 	    newval == ZFS_CACHE_METADATA);
239 
240 	os->os_secondary_cache = newval;
241 }
242 
243 static void
sync_changed_cb(void * arg,uint64_t newval)244 sync_changed_cb(void *arg, uint64_t newval)
245 {
246 	objset_t *os = arg;
247 
248 	/*
249 	 * Inheritance and range checking should have been done by now.
250 	 */
251 	ASSERT(newval == ZFS_SYNC_STANDARD || newval == ZFS_SYNC_ALWAYS ||
252 	    newval == ZFS_SYNC_DISABLED);
253 
254 	os->os_sync = newval;
255 	if (os->os_zil)
256 		zil_set_sync(os->os_zil, newval);
257 }
258 
259 static void
redundant_metadata_changed_cb(void * arg,uint64_t newval)260 redundant_metadata_changed_cb(void *arg, uint64_t newval)
261 {
262 	objset_t *os = arg;
263 
264 	/*
265 	 * Inheritance and range checking should have been done by now.
266 	 */
267 	ASSERT(newval == ZFS_REDUNDANT_METADATA_ALL ||
268 	    newval == ZFS_REDUNDANT_METADATA_MOST);
269 
270 	os->os_redundant_metadata = newval;
271 }
272 
273 static void
logbias_changed_cb(void * arg,uint64_t newval)274 logbias_changed_cb(void *arg, uint64_t newval)
275 {
276 	objset_t *os = arg;
277 
278 	ASSERT(newval == ZFS_LOGBIAS_LATENCY ||
279 	    newval == ZFS_LOGBIAS_THROUGHPUT);
280 	os->os_logbias = newval;
281 	if (os->os_zil)
282 		zil_set_logbias(os->os_zil, newval);
283 }
284 
285 static void
recordsize_changed_cb(void * arg,uint64_t newval)286 recordsize_changed_cb(void *arg, uint64_t newval)
287 {
288 	objset_t *os = arg;
289 
290 	os->os_recordsize = newval;
291 }
292 
293 void
dmu_objset_byteswap(void * buf,size_t size)294 dmu_objset_byteswap(void *buf, size_t size)
295 {
296 	objset_phys_t *osp = buf;
297 
298 	ASSERT(size == OBJSET_OLD_PHYS_SIZE || size == sizeof (objset_phys_t));
299 	dnode_byteswap(&osp->os_meta_dnode);
300 	byteswap_uint64_array(&osp->os_zil_header, sizeof (zil_header_t));
301 	osp->os_type = BSWAP_64(osp->os_type);
302 	osp->os_flags = BSWAP_64(osp->os_flags);
303 	if (size == sizeof (objset_phys_t)) {
304 		dnode_byteswap(&osp->os_userused_dnode);
305 		dnode_byteswap(&osp->os_groupused_dnode);
306 	}
307 }
308 
309 /*
310  * The hash is a CRC-based hash of the objset_t pointer and the object number.
311  */
312 static uint64_t
dnode_hash(const objset_t * os,uint64_t obj)313 dnode_hash(const objset_t *os, uint64_t obj)
314 {
315 	uintptr_t osv = (uintptr_t)os;
316 	uint64_t crc = -1ULL;
317 
318 	ASSERT(zfs_crc64_table[128] == ZFS_CRC64_POLY);
319 	/*
320 	 * The low 6 bits of the pointer don't have much entropy, because
321 	 * the objset_t is larger than 2^6 bytes long.
322 	 */
323 	crc = (crc >> 8) ^ zfs_crc64_table[(crc ^ (osv >> 6)) & 0xFF];
324 	crc = (crc >> 8) ^ zfs_crc64_table[(crc ^ (obj >> 0)) & 0xFF];
325 	crc = (crc >> 8) ^ zfs_crc64_table[(crc ^ (obj >> 8)) & 0xFF];
326 	crc = (crc >> 8) ^ zfs_crc64_table[(crc ^ (obj >> 16)) & 0xFF];
327 
328 	crc ^= (osv>>14) ^ (obj>>24);
329 
330 	return (crc);
331 }
332 
333 unsigned int
dnode_multilist_index_func(multilist_t * ml,void * obj)334 dnode_multilist_index_func(multilist_t *ml, void *obj)
335 {
336 	dnode_t *dn = obj;
337 	return (dnode_hash(dn->dn_objset, dn->dn_object) %
338 	    multilist_get_num_sublists(ml));
339 }
340 
341 /*
342  * Instantiates the objset_t in-memory structure corresponding to the
343  * objset_phys_t that's pointed to by the specified blkptr_t.
344  */
345 int
dmu_objset_open_impl(spa_t * spa,dsl_dataset_t * ds,blkptr_t * bp,objset_t ** osp)346 dmu_objset_open_impl(spa_t *spa, dsl_dataset_t *ds, blkptr_t *bp,
347     objset_t **osp)
348 {
349 	objset_t *os;
350 	int i, err;
351 
352 	ASSERT(ds == NULL || MUTEX_HELD(&ds->ds_opening_lock));
353 
354 #if 0
355 	/*
356 	 * The $ORIGIN dataset (if it exists) doesn't have an associated
357 	 * objset, so there's no reason to open it. The $ORIGIN dataset
358 	 * will not exist on pools older than SPA_VERSION_ORIGIN.
359 	 */
360 	if (ds != NULL && spa_get_dsl(spa) != NULL &&
361 	    spa_get_dsl(spa)->dp_origin_snap != NULL) {
362 		ASSERT3P(ds->ds_dir, !=,
363 		    spa_get_dsl(spa)->dp_origin_snap->ds_dir);
364 	}
365 #endif
366 
367 	os = kmem_zalloc(sizeof (objset_t), KM_SLEEP);
368 	os->os_dsl_dataset = ds;
369 	os->os_spa = spa;
370 	os->os_rootbp = bp;
371 	if (!BP_IS_HOLE(os->os_rootbp)) {
372 		arc_flags_t aflags = ARC_FLAG_WAIT;
373 		zbookmark_phys_t zb;
374 		SET_BOOKMARK(&zb, ds ? ds->ds_object : DMU_META_OBJSET,
375 		    ZB_ROOT_OBJECT, ZB_ROOT_LEVEL, ZB_ROOT_BLKID);
376 
377 		if (DMU_OS_IS_L2CACHEABLE(os))
378 			aflags |= ARC_FLAG_L2CACHE;
379 
380 		dprintf_bp(os->os_rootbp, "reading %s", "");
381 		err = arc_read(NULL, spa, os->os_rootbp,
382 		    arc_getbuf_func, &os->os_phys_buf,
383 		    ZIO_PRIORITY_SYNC_READ, ZIO_FLAG_CANFAIL, &aflags, &zb);
384 		if (err != 0) {
385 			kmem_free(os, sizeof (objset_t));
386 			/* convert checksum errors into IO errors */
387 			if (err == ECKSUM)
388 				err = SET_ERROR(EIO);
389 			return (err);
390 		}
391 
392 		/* Increase the blocksize if we are permitted. */
393 		if (spa_version(spa) >= SPA_VERSION_USERSPACE &&
394 		    arc_buf_size(os->os_phys_buf) < sizeof (objset_phys_t)) {
395 			arc_buf_t *buf = arc_alloc_buf(spa, &os->os_phys_buf,
396 			    ARC_BUFC_METADATA, sizeof (objset_phys_t));
397 			bzero(buf->b_data, sizeof (objset_phys_t));
398 			bcopy(os->os_phys_buf->b_data, buf->b_data,
399 			    arc_buf_size(os->os_phys_buf));
400 			arc_buf_destroy(os->os_phys_buf, &os->os_phys_buf);
401 			os->os_phys_buf = buf;
402 		}
403 
404 		os->os_phys = os->os_phys_buf->b_data;
405 		os->os_flags = os->os_phys->os_flags;
406 	} else {
407 		int size = spa_version(spa) >= SPA_VERSION_USERSPACE ?
408 		    sizeof (objset_phys_t) : OBJSET_OLD_PHYS_SIZE;
409 		os->os_phys_buf = arc_alloc_buf(spa, &os->os_phys_buf,
410 		    ARC_BUFC_METADATA, size);
411 		os->os_phys = os->os_phys_buf->b_data;
412 		bzero(os->os_phys, size);
413 	}
414 
415 	/*
416 	 * Note: the changed_cb will be called once before the register
417 	 * func returns, thus changing the checksum/compression from the
418 	 * default (fletcher2/off).  Snapshots don't need to know about
419 	 * checksum/compression/copies.
420 	 */
421 	if (ds != NULL) {
422 		boolean_t needlock = B_FALSE;
423 
424 		/*
425 		 * Note: it's valid to open the objset if the dataset is
426 		 * long-held, in which case the pool_config lock will not
427 		 * be held.
428 		 */
429 		if (!dsl_pool_config_held(dmu_objset_pool(os))) {
430 			needlock = B_TRUE;
431 			dsl_pool_config_enter(dmu_objset_pool(os), FTAG);
432 		}
433 		err = dsl_prop_register(ds,
434 		    zfs_prop_to_name(ZFS_PROP_PRIMARYCACHE),
435 		    primary_cache_changed_cb, os);
436 		if (err == 0) {
437 			err = dsl_prop_register(ds,
438 			    zfs_prop_to_name(ZFS_PROP_SECONDARYCACHE),
439 			    secondary_cache_changed_cb, os);
440 		}
441 		if (!ds->ds_is_snapshot) {
442 			if (err == 0) {
443 				err = dsl_prop_register(ds,
444 				    zfs_prop_to_name(ZFS_PROP_CHECKSUM),
445 				    checksum_changed_cb, os);
446 			}
447 			if (err == 0) {
448 				err = dsl_prop_register(ds,
449 				    zfs_prop_to_name(ZFS_PROP_COMPRESSION),
450 				    compression_changed_cb, os);
451 			}
452 			if (err == 0) {
453 				err = dsl_prop_register(ds,
454 				    zfs_prop_to_name(ZFS_PROP_COPIES),
455 				    copies_changed_cb, os);
456 			}
457 			if (err == 0) {
458 				err = dsl_prop_register(ds,
459 				    zfs_prop_to_name(ZFS_PROP_DEDUP),
460 				    dedup_changed_cb, os);
461 			}
462 			if (err == 0) {
463 				err = dsl_prop_register(ds,
464 				    zfs_prop_to_name(ZFS_PROP_LOGBIAS),
465 				    logbias_changed_cb, os);
466 			}
467 			if (err == 0) {
468 				err = dsl_prop_register(ds,
469 				    zfs_prop_to_name(ZFS_PROP_SYNC),
470 				    sync_changed_cb, os);
471 			}
472 			if (err == 0) {
473 				err = dsl_prop_register(ds,
474 				    zfs_prop_to_name(
475 				    ZFS_PROP_REDUNDANT_METADATA),
476 				    redundant_metadata_changed_cb, os);
477 			}
478 			if (err == 0) {
479 				err = dsl_prop_register(ds,
480 				    zfs_prop_to_name(ZFS_PROP_RECORDSIZE),
481 				    recordsize_changed_cb, os);
482 			}
483 		}
484 		if (needlock)
485 			dsl_pool_config_exit(dmu_objset_pool(os), FTAG);
486 		if (err != 0) {
487 			arc_buf_destroy(os->os_phys_buf, &os->os_phys_buf);
488 			kmem_free(os, sizeof (objset_t));
489 			return (err);
490 		}
491 	} else {
492 		/* It's the meta-objset. */
493 		os->os_checksum = ZIO_CHECKSUM_FLETCHER_4;
494 		os->os_compress = ZIO_COMPRESS_ON;
495 		os->os_copies = spa_max_replication(spa);
496 		os->os_dedup_checksum = ZIO_CHECKSUM_OFF;
497 		os->os_dedup_verify = B_FALSE;
498 		os->os_logbias = ZFS_LOGBIAS_LATENCY;
499 		os->os_sync = ZFS_SYNC_STANDARD;
500 		os->os_primary_cache = ZFS_CACHE_ALL;
501 		os->os_secondary_cache = ZFS_CACHE_ALL;
502 	}
503 	/*
504 	 * These properties will be filled in by the logic in zfs_get_zplprop()
505 	 * when they are queried for the first time.
506 	 */
507 	os->os_version = OBJSET_PROP_UNINITIALIZED;
508 	os->os_normalization = OBJSET_PROP_UNINITIALIZED;
509 	os->os_utf8only = OBJSET_PROP_UNINITIALIZED;
510 	os->os_casesensitivity = OBJSET_PROP_UNINITIALIZED;
511 
512 	if (ds == NULL || !ds->ds_is_snapshot)
513 		os->os_zil_header = os->os_phys->os_zil_header;
514 	os->os_zil = zil_alloc(os, &os->os_zil_header);
515 
516 	for (i = 0; i < TXG_SIZE; i++) {
517 		os->os_dirty_dnodes[i] = multilist_create(sizeof (dnode_t),
518 		    offsetof(dnode_t, dn_dirty_link[i]),
519 		    dnode_multilist_index_func);
520 	}
521 	list_create(&os->os_dnodes, sizeof (dnode_t),
522 	    offsetof(dnode_t, dn_link));
523 	list_create(&os->os_downgraded_dbufs, sizeof (dmu_buf_impl_t),
524 	    offsetof(dmu_buf_impl_t, db_link));
525 
526 	mutex_init(&os->os_lock, NULL, MUTEX_DEFAULT, NULL);
527 	mutex_init(&os->os_userused_lock, NULL, MUTEX_DEFAULT, NULL);
528 	mutex_init(&os->os_obj_lock, NULL, MUTEX_DEFAULT, NULL);
529 	mutex_init(&os->os_user_ptr_lock, NULL, MUTEX_DEFAULT, NULL);
530 
531 	dnode_special_open(os, &os->os_phys->os_meta_dnode,
532 	    DMU_META_DNODE_OBJECT, &os->os_meta_dnode);
533 	if (arc_buf_size(os->os_phys_buf) >= sizeof (objset_phys_t)) {
534 		dnode_special_open(os, &os->os_phys->os_userused_dnode,
535 		    DMU_USERUSED_OBJECT, &os->os_userused_dnode);
536 		dnode_special_open(os, &os->os_phys->os_groupused_dnode,
537 		    DMU_GROUPUSED_OBJECT, &os->os_groupused_dnode);
538 	}
539 
540 	*osp = os;
541 	return (0);
542 }
543 
544 int
dmu_objset_from_ds(dsl_dataset_t * ds,objset_t ** osp)545 dmu_objset_from_ds(dsl_dataset_t *ds, objset_t **osp)
546 {
547 	int err = 0;
548 
549 	/*
550 	 * We shouldn't be doing anything with dsl_dataset_t's unless the
551 	 * pool_config lock is held, or the dataset is long-held.
552 	 */
553 	ASSERT(dsl_pool_config_held(ds->ds_dir->dd_pool) ||
554 	    dsl_dataset_long_held(ds));
555 
556 	mutex_enter(&ds->ds_opening_lock);
557 	if (ds->ds_objset == NULL) {
558 		objset_t *os;
559 		rrw_enter(&ds->ds_bp_rwlock, RW_READER, FTAG);
560 		err = dmu_objset_open_impl(dsl_dataset_get_spa(ds),
561 		    ds, dsl_dataset_get_blkptr(ds), &os);
562 		rrw_exit(&ds->ds_bp_rwlock, FTAG);
563 
564 		if (err == 0) {
565 			mutex_enter(&ds->ds_lock);
566 			ASSERT(ds->ds_objset == NULL);
567 			ds->ds_objset = os;
568 			mutex_exit(&ds->ds_lock);
569 		}
570 	}
571 	*osp = ds->ds_objset;
572 	mutex_exit(&ds->ds_opening_lock);
573 	return (err);
574 }
575 
576 /*
577  * Holds the pool while the objset is held.  Therefore only one objset
578  * can be held at a time.
579  */
580 int
dmu_objset_hold(const char * name,void * tag,objset_t ** osp)581 dmu_objset_hold(const char *name, void *tag, objset_t **osp)
582 {
583 	dsl_pool_t *dp;
584 	dsl_dataset_t *ds;
585 	int err;
586 
587 	err = dsl_pool_hold(name, tag, &dp);
588 	if (err != 0)
589 		return (err);
590 	err = dsl_dataset_hold(dp, name, tag, &ds);
591 	if (err != 0) {
592 		dsl_pool_rele(dp, tag);
593 		return (err);
594 	}
595 
596 	err = dmu_objset_from_ds(ds, osp);
597 	if (err != 0) {
598 		dsl_dataset_rele(ds, tag);
599 		dsl_pool_rele(dp, tag);
600 	}
601 
602 	return (err);
603 }
604 
605 static int
dmu_objset_own_impl(dsl_dataset_t * ds,dmu_objset_type_t type,boolean_t readonly,void * tag,objset_t ** osp)606 dmu_objset_own_impl(dsl_dataset_t *ds, dmu_objset_type_t type,
607     boolean_t readonly, void *tag, objset_t **osp)
608 {
609 	int err;
610 
611 	err = dmu_objset_from_ds(ds, osp);
612 	if (err != 0) {
613 		dsl_dataset_disown(ds, tag);
614 	} else if (type != DMU_OST_ANY && type != (*osp)->os_phys->os_type) {
615 		dsl_dataset_disown(ds, tag);
616 		return (SET_ERROR(EINVAL));
617 	} else if (!readonly && dsl_dataset_is_snapshot(ds)) {
618 		dsl_dataset_disown(ds, tag);
619 		return (SET_ERROR(EROFS));
620 	}
621 	return (err);
622 }
623 
624 /*
625  * dsl_pool must not be held when this is called.
626  * Upon successful return, there will be a longhold on the dataset,
627  * and the dsl_pool will not be held.
628  */
629 int
dmu_objset_own(const char * name,dmu_objset_type_t type,boolean_t readonly,void * tag,objset_t ** osp)630 dmu_objset_own(const char *name, dmu_objset_type_t type,
631     boolean_t readonly, void *tag, objset_t **osp)
632 {
633 	dsl_pool_t *dp;
634 	dsl_dataset_t *ds;
635 	int err;
636 
637 	err = dsl_pool_hold(name, FTAG, &dp);
638 	if (err != 0)
639 		return (err);
640 	err = dsl_dataset_own(dp, name, tag, &ds);
641 	if (err != 0) {
642 		dsl_pool_rele(dp, FTAG);
643 		return (err);
644 	}
645 	err = dmu_objset_own_impl(ds, type, readonly, tag, osp);
646 	dsl_pool_rele(dp, FTAG);
647 
648 	return (err);
649 }
650 
651 int
dmu_objset_own_obj(dsl_pool_t * dp,uint64_t obj,dmu_objset_type_t type,boolean_t readonly,void * tag,objset_t ** osp)652 dmu_objset_own_obj(dsl_pool_t *dp, uint64_t obj, dmu_objset_type_t type,
653     boolean_t readonly, void *tag, objset_t **osp)
654 {
655 	dsl_dataset_t *ds;
656 	int err;
657 
658 	err = dsl_dataset_own_obj(dp, obj, tag, &ds);
659 	if (err != 0)
660 		return (err);
661 
662 	return (dmu_objset_own_impl(ds, type, readonly, tag, osp));
663 }
664 
665 void
dmu_objset_rele(objset_t * os,void * tag)666 dmu_objset_rele(objset_t *os, void *tag)
667 {
668 	dsl_pool_t *dp = dmu_objset_pool(os);
669 	dsl_dataset_rele(os->os_dsl_dataset, tag);
670 	dsl_pool_rele(dp, tag);
671 }
672 
673 /*
674  * When we are called, os MUST refer to an objset associated with a dataset
675  * that is owned by 'tag'; that is, is held and long held by 'tag' and ds_owner
676  * == tag.  We will then release and reacquire ownership of the dataset while
677  * holding the pool config_rwlock to avoid intervening namespace or ownership
678  * changes may occur.
679  *
680  * This exists solely to accommodate zfs_ioc_userspace_upgrade()'s desire to
681  * release the hold on its dataset and acquire a new one on the dataset of the
682  * same name so that it can be partially torn down and reconstructed.
683  */
684 void
dmu_objset_refresh_ownership(dsl_dataset_t * ds,dsl_dataset_t ** newds,void * tag)685 dmu_objset_refresh_ownership(dsl_dataset_t *ds, dsl_dataset_t **newds,
686     void *tag)
687 {
688 	dsl_pool_t *dp;
689 	char name[ZFS_MAX_DATASET_NAME_LEN];
690 
691 	VERIFY3P(ds, !=, NULL);
692 	VERIFY3P(ds->ds_owner, ==, tag);
693 	VERIFY(dsl_dataset_long_held(ds));
694 
695 	dsl_dataset_name(ds, name);
696 	dp = ds->ds_dir->dd_pool;
697 	dsl_pool_config_enter(dp, FTAG);
698 	dsl_dataset_disown(ds, tag);
699 	VERIFY0(dsl_dataset_own(dp, name, tag, newds));
700 	dsl_pool_config_exit(dp, FTAG);
701 }
702 
703 void
dmu_objset_disown(objset_t * os,void * tag)704 dmu_objset_disown(objset_t *os, void *tag)
705 {
706 	dsl_dataset_disown(os->os_dsl_dataset, tag);
707 }
708 
709 void
dmu_objset_evict_dbufs(objset_t * os)710 dmu_objset_evict_dbufs(objset_t *os)
711 {
712 	dnode_t dn_marker;
713 	dnode_t *dn;
714 
715 	mutex_enter(&os->os_lock);
716 	dn = list_head(&os->os_dnodes);
717 	while (dn != NULL) {
718 		/*
719 		 * Skip dnodes without holds.  We have to do this dance
720 		 * because dnode_add_ref() only works if there is already a
721 		 * hold.  If the dnode has no holds, then it has no dbufs.
722 		 */
723 		if (dnode_add_ref(dn, FTAG)) {
724 			list_insert_after(&os->os_dnodes, dn, &dn_marker);
725 			mutex_exit(&os->os_lock);
726 
727 			dnode_evict_dbufs(dn);
728 			dnode_rele(dn, FTAG);
729 
730 			mutex_enter(&os->os_lock);
731 			dn = list_next(&os->os_dnodes, &dn_marker);
732 			list_remove(&os->os_dnodes, &dn_marker);
733 		} else {
734 			dn = list_next(&os->os_dnodes, dn);
735 		}
736 	}
737 	mutex_exit(&os->os_lock);
738 
739 	if (DMU_USERUSED_DNODE(os) != NULL) {
740 		dnode_evict_dbufs(DMU_GROUPUSED_DNODE(os));
741 		dnode_evict_dbufs(DMU_USERUSED_DNODE(os));
742 	}
743 	dnode_evict_dbufs(DMU_META_DNODE(os));
744 }
745 
746 /*
747  * Objset eviction processing is split into into two pieces.
748  * The first marks the objset as evicting, evicts any dbufs that
749  * have a refcount of zero, and then queues up the objset for the
750  * second phase of eviction.  Once os->os_dnodes has been cleared by
751  * dnode_buf_pageout()->dnode_destroy(), the second phase is executed.
752  * The second phase closes the special dnodes, dequeues the objset from
753  * the list of those undergoing eviction, and finally frees the objset.
754  *
755  * NOTE: Due to asynchronous eviction processing (invocation of
756  *       dnode_buf_pageout()), it is possible for the meta dnode for the
757  *       objset to have no holds even though os->os_dnodes is not empty.
758  */
759 void
dmu_objset_evict(objset_t * os)760 dmu_objset_evict(objset_t *os)
761 {
762 	dsl_dataset_t *ds = os->os_dsl_dataset;
763 
764 	for (int t = 0; t < TXG_SIZE; t++)
765 		ASSERT(!dmu_objset_is_dirty(os, t));
766 
767 	if (ds)
768 		dsl_prop_unregister_all(ds, os);
769 
770 	if (os->os_sa)
771 		sa_tear_down(os);
772 
773 	dmu_objset_evict_dbufs(os);
774 
775 	mutex_enter(&os->os_lock);
776 	spa_evicting_os_register(os->os_spa, os);
777 	if (list_is_empty(&os->os_dnodes)) {
778 		mutex_exit(&os->os_lock);
779 		dmu_objset_evict_done(os);
780 	} else {
781 		mutex_exit(&os->os_lock);
782 	}
783 }
784 
785 void
dmu_objset_evict_done(objset_t * os)786 dmu_objset_evict_done(objset_t *os)
787 {
788 	ASSERT3P(list_head(&os->os_dnodes), ==, NULL);
789 
790 	dnode_special_close(&os->os_meta_dnode);
791 	if (DMU_USERUSED_DNODE(os)) {
792 		dnode_special_close(&os->os_userused_dnode);
793 		dnode_special_close(&os->os_groupused_dnode);
794 	}
795 	zil_free(os->os_zil);
796 
797 	arc_buf_destroy(os->os_phys_buf, &os->os_phys_buf);
798 
799 	/*
800 	 * This is a barrier to prevent the objset from going away in
801 	 * dnode_move() until we can safely ensure that the objset is still in
802 	 * use. We consider the objset valid before the barrier and invalid
803 	 * after the barrier.
804 	 */
805 	rw_enter(&os_lock, RW_READER);
806 	rw_exit(&os_lock);
807 
808 	mutex_destroy(&os->os_lock);
809 	mutex_destroy(&os->os_userused_lock);
810 	mutex_destroy(&os->os_obj_lock);
811 	mutex_destroy(&os->os_user_ptr_lock);
812 	for (int i = 0; i < TXG_SIZE; i++) {
813 		multilist_destroy(os->os_dirty_dnodes[i]);
814 	}
815 	spa_evicting_os_deregister(os->os_spa, os);
816 	kmem_free(os, sizeof (objset_t));
817 }
818 
819 timestruc_t
dmu_objset_snap_cmtime(objset_t * os)820 dmu_objset_snap_cmtime(objset_t *os)
821 {
822 	return (dsl_dir_snap_cmtime(os->os_dsl_dataset->ds_dir));
823 }
824 
825 /* called from dsl for meta-objset */
826 objset_t *
dmu_objset_create_impl(spa_t * spa,dsl_dataset_t * ds,blkptr_t * bp,dmu_objset_type_t type,dmu_tx_t * tx)827 dmu_objset_create_impl(spa_t *spa, dsl_dataset_t *ds, blkptr_t *bp,
828     dmu_objset_type_t type, dmu_tx_t *tx)
829 {
830 	objset_t *os;
831 	dnode_t *mdn;
832 
833 	ASSERT(dmu_tx_is_syncing(tx));
834 
835 	if (ds != NULL)
836 		VERIFY0(dmu_objset_from_ds(ds, &os));
837 	else
838 		VERIFY0(dmu_objset_open_impl(spa, NULL, bp, &os));
839 
840 	mdn = DMU_META_DNODE(os);
841 
842 	dnode_allocate(mdn, DMU_OT_DNODE, 1 << DNODE_BLOCK_SHIFT,
843 	    DN_MAX_INDBLKSHIFT, DMU_OT_NONE, 0, tx);
844 
845 	/*
846 	 * We don't want to have to increase the meta-dnode's nlevels
847 	 * later, because then we could do it in quescing context while
848 	 * we are also accessing it in open context.
849 	 *
850 	 * This precaution is not necessary for the MOS (ds == NULL),
851 	 * because the MOS is only updated in syncing context.
852 	 * This is most fortunate: the MOS is the only objset that
853 	 * needs to be synced multiple times as spa_sync() iterates
854 	 * to convergence, so minimizing its dn_nlevels matters.
855 	 */
856 	if (ds != NULL) {
857 		int levels = 1;
858 
859 		/*
860 		 * Determine the number of levels necessary for the meta-dnode
861 		 * to contain DN_MAX_OBJECT dnodes.  Note that in order to
862 		 * ensure that we do not overflow 64 bits, there has to be
863 		 * a nlevels that gives us a number of blocks > DN_MAX_OBJECT
864 		 * but < 2^64.  Therefore,
865 		 * (mdn->dn_indblkshift - SPA_BLKPTRSHIFT) (10) must be
866 		 * less than (64 - log2(DN_MAX_OBJECT)) (16).
867 		 */
868 		while ((uint64_t)mdn->dn_nblkptr <<
869 		    (mdn->dn_datablkshift - DNODE_SHIFT +
870 		    (levels - 1) * (mdn->dn_indblkshift - SPA_BLKPTRSHIFT)) <
871 		    DN_MAX_OBJECT)
872 			levels++;
873 
874 		mdn->dn_next_nlevels[tx->tx_txg & TXG_MASK] =
875 		    mdn->dn_nlevels = levels;
876 	}
877 
878 	ASSERT(type != DMU_OST_NONE);
879 	ASSERT(type != DMU_OST_ANY);
880 	ASSERT(type < DMU_OST_NUMTYPES);
881 	os->os_phys->os_type = type;
882 	if (dmu_objset_userused_enabled(os)) {
883 		os->os_phys->os_flags |= OBJSET_FLAG_USERACCOUNTING_COMPLETE;
884 		os->os_flags = os->os_phys->os_flags;
885 	}
886 
887 	dsl_dataset_dirty(ds, tx);
888 
889 	return (os);
890 }
891 
892 typedef struct dmu_objset_create_arg {
893 	const char *doca_name;
894 	cred_t *doca_cred;
895 	void (*doca_userfunc)(objset_t *os, void *arg,
896 	    cred_t *cr, dmu_tx_t *tx);
897 	void *doca_userarg;
898 	dmu_objset_type_t doca_type;
899 	uint64_t doca_flags;
900 } dmu_objset_create_arg_t;
901 
902 /*ARGSUSED*/
903 static int
dmu_objset_create_check(void * arg,dmu_tx_t * tx)904 dmu_objset_create_check(void *arg, dmu_tx_t *tx)
905 {
906 	dmu_objset_create_arg_t *doca = arg;
907 	dsl_pool_t *dp = dmu_tx_pool(tx);
908 	dsl_dir_t *pdd;
909 	dsl_dataset_t *parentds;
910 	objset_t *parentos;
911 	const char *tail;
912 	int error;
913 
914 	if (strchr(doca->doca_name, '@') != NULL)
915 		return (SET_ERROR(EINVAL));
916 
917 	if (strlen(doca->doca_name) >= ZFS_MAX_DATASET_NAME_LEN)
918 		return (SET_ERROR(ENAMETOOLONG));
919 
920 	if (dataset_nestcheck(doca->doca_name) != 0)
921 		return (SET_ERROR(ENAMETOOLONG));
922 
923 	error = dsl_dir_hold(dp, doca->doca_name, FTAG, &pdd, &tail);
924 	if (error != 0)
925 		return (error);
926 	if (tail == NULL) {
927 		dsl_dir_rele(pdd, FTAG);
928 		return (SET_ERROR(EEXIST));
929 	}
930 	error = dsl_fs_ss_limit_check(pdd, 1, ZFS_PROP_FILESYSTEM_LIMIT, NULL,
931 	    doca->doca_cred);
932 	if (error != 0) {
933 		dsl_dir_rele(pdd, FTAG);
934 		return (error);
935 	}
936 
937 	/* can't create below anything but filesystems (eg. no ZVOLs) */
938 	error = dsl_dataset_hold_obj(pdd->dd_pool,
939 	    dsl_dir_phys(pdd)->dd_head_dataset_obj, FTAG, &parentds);
940 	if (error != 0) {
941 		dsl_dir_rele(pdd, FTAG);
942 		return (error);
943 	}
944 	error = dmu_objset_from_ds(parentds, &parentos);
945 	if (error != 0) {
946 		dsl_dataset_rele(parentds, FTAG);
947 		dsl_dir_rele(pdd, FTAG);
948 		return (error);
949 	}
950 	if (dmu_objset_type(parentos) != DMU_OST_ZFS) {
951 		dsl_dataset_rele(parentds, FTAG);
952 		dsl_dir_rele(pdd, FTAG);
953 		return (SET_ERROR(ZFS_ERR_WRONG_PARENT));
954 	}
955 	dsl_dataset_rele(parentds, FTAG);
956 	dsl_dir_rele(pdd, FTAG);
957 
958 	return (error);
959 }
960 
961 static void
dmu_objset_create_sync(void * arg,dmu_tx_t * tx)962 dmu_objset_create_sync(void *arg, dmu_tx_t *tx)
963 {
964 	dmu_objset_create_arg_t *doca = arg;
965 	dsl_pool_t *dp = dmu_tx_pool(tx);
966 	dsl_dir_t *pdd;
967 	const char *tail;
968 	dsl_dataset_t *ds;
969 	uint64_t obj;
970 	blkptr_t *bp;
971 	objset_t *os;
972 
973 	VERIFY0(dsl_dir_hold(dp, doca->doca_name, FTAG, &pdd, &tail));
974 
975 	obj = dsl_dataset_create_sync(pdd, tail, NULL, doca->doca_flags,
976 	    doca->doca_cred, tx);
977 
978 	VERIFY0(dsl_dataset_hold_obj(pdd->dd_pool, obj, FTAG, &ds));
979 	rrw_enter(&ds->ds_bp_rwlock, RW_READER, FTAG);
980 	bp = dsl_dataset_get_blkptr(ds);
981 	os = dmu_objset_create_impl(pdd->dd_pool->dp_spa,
982 	    ds, bp, doca->doca_type, tx);
983 	rrw_exit(&ds->ds_bp_rwlock, FTAG);
984 
985 	if (doca->doca_userfunc != NULL) {
986 		doca->doca_userfunc(os, doca->doca_userarg,
987 		    doca->doca_cred, tx);
988 	}
989 
990 	spa_history_log_internal_ds(ds, "create", tx, "");
991 	dsl_dataset_rele(ds, FTAG);
992 	dsl_dir_rele(pdd, FTAG);
993 }
994 
995 int
dmu_objset_create(const char * name,dmu_objset_type_t type,uint64_t flags,void (* func)(objset_t * os,void * arg,cred_t * cr,dmu_tx_t * tx),void * arg)996 dmu_objset_create(const char *name, dmu_objset_type_t type, uint64_t flags,
997     void (*func)(objset_t *os, void *arg, cred_t *cr, dmu_tx_t *tx), void *arg)
998 {
999 	dmu_objset_create_arg_t doca;
1000 
1001 	doca.doca_name = name;
1002 	doca.doca_cred = CRED();
1003 	doca.doca_flags = flags;
1004 	doca.doca_userfunc = func;
1005 	doca.doca_userarg = arg;
1006 	doca.doca_type = type;
1007 
1008 	return (dsl_sync_task(name,
1009 	    dmu_objset_create_check, dmu_objset_create_sync, &doca,
1010 	    5, ZFS_SPACE_CHECK_NORMAL));
1011 }
1012 
1013 typedef struct dmu_objset_clone_arg {
1014 	const char *doca_clone;
1015 	const char *doca_origin;
1016 	cred_t *doca_cred;
1017 } dmu_objset_clone_arg_t;
1018 
1019 /*ARGSUSED*/
1020 static int
dmu_objset_clone_check(void * arg,dmu_tx_t * tx)1021 dmu_objset_clone_check(void *arg, dmu_tx_t *tx)
1022 {
1023 	dmu_objset_clone_arg_t *doca = arg;
1024 	dsl_dir_t *pdd;
1025 	const char *tail;
1026 	int error;
1027 	dsl_dataset_t *origin;
1028 	dsl_pool_t *dp = dmu_tx_pool(tx);
1029 
1030 	if (strchr(doca->doca_clone, '@') != NULL)
1031 		return (SET_ERROR(EINVAL));
1032 
1033 	if (strlen(doca->doca_clone) >= ZFS_MAX_DATASET_NAME_LEN)
1034 		return (SET_ERROR(ENAMETOOLONG));
1035 
1036 	error = dsl_dir_hold(dp, doca->doca_clone, FTAG, &pdd, &tail);
1037 	if (error != 0)
1038 		return (error);
1039 	if (tail == NULL) {
1040 		dsl_dir_rele(pdd, FTAG);
1041 		return (SET_ERROR(EEXIST));
1042 	}
1043 
1044 	error = dsl_fs_ss_limit_check(pdd, 1, ZFS_PROP_FILESYSTEM_LIMIT, NULL,
1045 	    doca->doca_cred);
1046 	if (error != 0) {
1047 		dsl_dir_rele(pdd, FTAG);
1048 		return (SET_ERROR(EDQUOT));
1049 	}
1050 	dsl_dir_rele(pdd, FTAG);
1051 
1052 	error = dsl_dataset_hold(dp, doca->doca_origin, FTAG, &origin);
1053 	if (error != 0)
1054 		return (error);
1055 
1056 	/* You can only clone snapshots, not the head datasets. */
1057 	if (!origin->ds_is_snapshot) {
1058 		dsl_dataset_rele(origin, FTAG);
1059 		return (SET_ERROR(EINVAL));
1060 	}
1061 	dsl_dataset_rele(origin, FTAG);
1062 
1063 	return (0);
1064 }
1065 
1066 static void
dmu_objset_clone_sync(void * arg,dmu_tx_t * tx)1067 dmu_objset_clone_sync(void *arg, dmu_tx_t *tx)
1068 {
1069 	dmu_objset_clone_arg_t *doca = arg;
1070 	dsl_pool_t *dp = dmu_tx_pool(tx);
1071 	dsl_dir_t *pdd;
1072 	const char *tail;
1073 	dsl_dataset_t *origin, *ds;
1074 	uint64_t obj;
1075 	char namebuf[ZFS_MAX_DATASET_NAME_LEN];
1076 
1077 	VERIFY0(dsl_dir_hold(dp, doca->doca_clone, FTAG, &pdd, &tail));
1078 	VERIFY0(dsl_dataset_hold(dp, doca->doca_origin, FTAG, &origin));
1079 
1080 	obj = dsl_dataset_create_sync(pdd, tail, origin, 0,
1081 	    doca->doca_cred, tx);
1082 
1083 	VERIFY0(dsl_dataset_hold_obj(pdd->dd_pool, obj, FTAG, &ds));
1084 	dsl_dataset_name(origin, namebuf);
1085 	spa_history_log_internal_ds(ds, "clone", tx,
1086 	    "origin=%s (%llu)", namebuf, origin->ds_object);
1087 	dsl_dataset_rele(ds, FTAG);
1088 	dsl_dataset_rele(origin, FTAG);
1089 	dsl_dir_rele(pdd, FTAG);
1090 }
1091 
1092 int
dmu_objset_clone(const char * clone,const char * origin)1093 dmu_objset_clone(const char *clone, const char *origin)
1094 {
1095 	dmu_objset_clone_arg_t doca;
1096 
1097 	doca.doca_clone = clone;
1098 	doca.doca_origin = origin;
1099 	doca.doca_cred = CRED();
1100 
1101 	return (dsl_sync_task(clone,
1102 	    dmu_objset_clone_check, dmu_objset_clone_sync, &doca,
1103 	    5, ZFS_SPACE_CHECK_NORMAL));
1104 }
1105 
1106 static int
dmu_objset_remap_indirects_impl(objset_t * os,uint64_t last_removed_txg)1107 dmu_objset_remap_indirects_impl(objset_t *os, uint64_t last_removed_txg)
1108 {
1109 	int error = 0;
1110 	uint64_t object = 0;
1111 	while ((error = dmu_object_next(os, &object, B_FALSE, 0)) == 0) {
1112 		error = dmu_object_remap_indirects(os, object,
1113 		    last_removed_txg);
1114 		/*
1115 		 * If the ZPL removed the object before we managed to dnode_hold
1116 		 * it, we would get an ENOENT. If the ZPL declares its intent
1117 		 * to remove the object (dnode_free) before we manage to
1118 		 * dnode_hold it, we would get an EEXIST. In either case, we
1119 		 * want to continue remapping the other objects in the objset;
1120 		 * in all other cases, we want to break early.
1121 		 */
1122 		if (error != 0 && error != ENOENT && error != EEXIST) {
1123 			break;
1124 		}
1125 	}
1126 	if (error == ESRCH) {
1127 		error = 0;
1128 	}
1129 	return (error);
1130 }
1131 
1132 int
dmu_objset_remap_indirects(const char * fsname)1133 dmu_objset_remap_indirects(const char *fsname)
1134 {
1135 	int error = 0;
1136 	objset_t *os = NULL;
1137 	uint64_t last_removed_txg;
1138 	uint64_t remap_start_txg;
1139 	dsl_dir_t *dd;
1140 
1141 	error = dmu_objset_hold(fsname, FTAG, &os);
1142 	if (error != 0) {
1143 		return (error);
1144 	}
1145 	dd = dmu_objset_ds(os)->ds_dir;
1146 
1147 	if (!spa_feature_is_enabled(dmu_objset_spa(os),
1148 	    SPA_FEATURE_OBSOLETE_COUNTS)) {
1149 		dmu_objset_rele(os, FTAG);
1150 		return (SET_ERROR(ENOTSUP));
1151 	}
1152 
1153 	if (dsl_dataset_is_snapshot(dmu_objset_ds(os))) {
1154 		dmu_objset_rele(os, FTAG);
1155 		return (SET_ERROR(EINVAL));
1156 	}
1157 
1158 	/*
1159 	 * If there has not been a removal, we're done.
1160 	 */
1161 	last_removed_txg = spa_get_last_removal_txg(dmu_objset_spa(os));
1162 	if (last_removed_txg == -1ULL) {
1163 		dmu_objset_rele(os, FTAG);
1164 		return (0);
1165 	}
1166 
1167 	/*
1168 	 * If we have remapped since the last removal, we're done.
1169 	 */
1170 	if (dsl_dir_is_zapified(dd)) {
1171 		uint64_t last_remap_txg;
1172 		if (zap_lookup(spa_meta_objset(dmu_objset_spa(os)),
1173 		    dd->dd_object, DD_FIELD_LAST_REMAP_TXG,
1174 		    sizeof (last_remap_txg), 1, &last_remap_txg) == 0 &&
1175 		    last_remap_txg > last_removed_txg) {
1176 			dmu_objset_rele(os, FTAG);
1177 			return (0);
1178 		}
1179 	}
1180 
1181 	dsl_dataset_long_hold(dmu_objset_ds(os), FTAG);
1182 	dsl_pool_rele(dmu_objset_pool(os), FTAG);
1183 
1184 	remap_start_txg = spa_last_synced_txg(dmu_objset_spa(os));
1185 	error = dmu_objset_remap_indirects_impl(os, last_removed_txg);
1186 	if (error == 0) {
1187 		/*
1188 		 * We update the last_remap_txg to be the start txg so that
1189 		 * we can guarantee that every block older than last_remap_txg
1190 		 * that can be remapped has been remapped.
1191 		 */
1192 		error = dsl_dir_update_last_remap_txg(dd, remap_start_txg);
1193 	}
1194 
1195 	dsl_dataset_long_rele(dmu_objset_ds(os), FTAG);
1196 	dsl_dataset_rele(dmu_objset_ds(os), FTAG);
1197 
1198 	return (error);
1199 }
1200 
1201 int
dmu_objset_snapshot_one(const char * fsname,const char * snapname)1202 dmu_objset_snapshot_one(const char *fsname, const char *snapname)
1203 {
1204 	int err;
1205 	char *longsnap = kmem_asprintf("%s@%s", fsname, snapname);
1206 	nvlist_t *snaps = fnvlist_alloc();
1207 
1208 	fnvlist_add_boolean(snaps, longsnap);
1209 	strfree(longsnap);
1210 	err = dsl_dataset_snapshot(snaps, NULL, NULL);
1211 	fnvlist_free(snaps);
1212 	return (err);
1213 }
1214 
1215 static void
dmu_objset_sync_dnodes(multilist_sublist_t * list,dmu_tx_t * tx)1216 dmu_objset_sync_dnodes(multilist_sublist_t *list, dmu_tx_t *tx)
1217 {
1218 	dnode_t *dn;
1219 
1220 	while ((dn = multilist_sublist_head(list)) != NULL) {
1221 		ASSERT(dn->dn_object != DMU_META_DNODE_OBJECT);
1222 		ASSERT(dn->dn_dbuf->db_data_pending);
1223 		/*
1224 		 * Initialize dn_zio outside dnode_sync() because the
1225 		 * meta-dnode needs to set it ouside dnode_sync().
1226 		 */
1227 		dn->dn_zio = dn->dn_dbuf->db_data_pending->dr_zio;
1228 		ASSERT(dn->dn_zio);
1229 
1230 		ASSERT3U(dn->dn_nlevels, <=, DN_MAX_LEVELS);
1231 		multilist_sublist_remove(list, dn);
1232 
1233 		multilist_t *newlist = dn->dn_objset->os_synced_dnodes;
1234 		if (newlist != NULL) {
1235 			(void) dnode_add_ref(dn, newlist);
1236 			multilist_insert(newlist, dn);
1237 		}
1238 
1239 		dnode_sync(dn, tx);
1240 	}
1241 }
1242 
1243 /* ARGSUSED */
1244 static void
dmu_objset_write_ready(zio_t * zio,arc_buf_t * abuf,void * arg)1245 dmu_objset_write_ready(zio_t *zio, arc_buf_t *abuf, void *arg)
1246 {
1247 	blkptr_t *bp = zio->io_bp;
1248 	objset_t *os = arg;
1249 	dnode_phys_t *dnp = &os->os_phys->os_meta_dnode;
1250 
1251 	ASSERT(!BP_IS_EMBEDDED(bp));
1252 	ASSERT3U(BP_GET_TYPE(bp), ==, DMU_OT_OBJSET);
1253 	ASSERT0(BP_GET_LEVEL(bp));
1254 
1255 	/*
1256 	 * Update rootbp fill count: it should be the number of objects
1257 	 * allocated in the object set (not counting the "special"
1258 	 * objects that are stored in the objset_phys_t -- the meta
1259 	 * dnode and user/group accounting objects).
1260 	 */
1261 	bp->blk_fill = 0;
1262 	for (int i = 0; i < dnp->dn_nblkptr; i++)
1263 		bp->blk_fill += BP_GET_FILL(&dnp->dn_blkptr[i]);
1264 	if (os->os_dsl_dataset != NULL)
1265 		rrw_enter(&os->os_dsl_dataset->ds_bp_rwlock, RW_WRITER, FTAG);
1266 	*os->os_rootbp = *bp;
1267 	if (os->os_dsl_dataset != NULL)
1268 		rrw_exit(&os->os_dsl_dataset->ds_bp_rwlock, FTAG);
1269 }
1270 
1271 /* ARGSUSED */
1272 static void
dmu_objset_write_done(zio_t * zio,arc_buf_t * abuf,void * arg)1273 dmu_objset_write_done(zio_t *zio, arc_buf_t *abuf, void *arg)
1274 {
1275 	blkptr_t *bp = zio->io_bp;
1276 	blkptr_t *bp_orig = &zio->io_bp_orig;
1277 	objset_t *os = arg;
1278 
1279 	if (zio->io_flags & ZIO_FLAG_IO_REWRITE) {
1280 		ASSERT(BP_EQUAL(bp, bp_orig));
1281 	} else {
1282 		dsl_dataset_t *ds = os->os_dsl_dataset;
1283 		dmu_tx_t *tx = os->os_synctx;
1284 
1285 		(void) dsl_dataset_block_kill(ds, bp_orig, tx, B_TRUE);
1286 		dsl_dataset_block_born(ds, bp, tx);
1287 	}
1288 	kmem_free(bp, sizeof (*bp));
1289 }
1290 
1291 typedef struct sync_dnodes_arg {
1292 	multilist_t *sda_list;
1293 	int sda_sublist_idx;
1294 	multilist_t *sda_newlist;
1295 	dmu_tx_t *sda_tx;
1296 } sync_dnodes_arg_t;
1297 
1298 static void
sync_dnodes_task(void * arg)1299 sync_dnodes_task(void *arg)
1300 {
1301 	sync_dnodes_arg_t *sda = arg;
1302 
1303 	multilist_sublist_t *ms =
1304 	    multilist_sublist_lock(sda->sda_list, sda->sda_sublist_idx);
1305 
1306 	dmu_objset_sync_dnodes(ms, sda->sda_tx);
1307 
1308 	multilist_sublist_unlock(ms);
1309 
1310 	kmem_free(sda, sizeof (*sda));
1311 }
1312 
1313 
1314 /* called from dsl */
1315 void
dmu_objset_sync(objset_t * os,zio_t * pio,dmu_tx_t * tx)1316 dmu_objset_sync(objset_t *os, zio_t *pio, dmu_tx_t *tx)
1317 {
1318 	int txgoff;
1319 	zbookmark_phys_t zb;
1320 	zio_prop_t zp;
1321 	zio_t *zio;
1322 	list_t *list;
1323 	dbuf_dirty_record_t *dr;
1324 	int num_sublists;
1325 	multilist_t *ml;
1326 	blkptr_t *blkptr_copy = kmem_alloc(sizeof (*os->os_rootbp), KM_SLEEP);
1327 	*blkptr_copy = *os->os_rootbp;
1328 
1329 	dprintf_ds(os->os_dsl_dataset, "txg=%llu\n", tx->tx_txg);
1330 
1331 	ASSERT(dmu_tx_is_syncing(tx));
1332 	/* XXX the write_done callback should really give us the tx... */
1333 	os->os_synctx = tx;
1334 
1335 	if (os->os_dsl_dataset == NULL) {
1336 		/*
1337 		 * This is the MOS.  If we have upgraded,
1338 		 * spa_max_replication() could change, so reset
1339 		 * os_copies here.
1340 		 */
1341 		os->os_copies = spa_max_replication(os->os_spa);
1342 	}
1343 
1344 	/*
1345 	 * Create the root block IO
1346 	 */
1347 	SET_BOOKMARK(&zb, os->os_dsl_dataset ?
1348 	    os->os_dsl_dataset->ds_object : DMU_META_OBJSET,
1349 	    ZB_ROOT_OBJECT, ZB_ROOT_LEVEL, ZB_ROOT_BLKID);
1350 	arc_release(os->os_phys_buf, &os->os_phys_buf);
1351 
1352 	dmu_write_policy(os, NULL, 0, 0, &zp);
1353 
1354 	zio = arc_write(pio, os->os_spa, tx->tx_txg,
1355 	    blkptr_copy, os->os_phys_buf, DMU_OS_IS_L2CACHEABLE(os),
1356 	    &zp, dmu_objset_write_ready, NULL, NULL, dmu_objset_write_done,
1357 	    os, ZIO_PRIORITY_ASYNC_WRITE, ZIO_FLAG_MUSTSUCCEED, &zb);
1358 
1359 	/*
1360 	 * Sync special dnodes - the parent IO for the sync is the root block
1361 	 */
1362 	DMU_META_DNODE(os)->dn_zio = zio;
1363 	dnode_sync(DMU_META_DNODE(os), tx);
1364 
1365 	os->os_phys->os_flags = os->os_flags;
1366 
1367 	if (DMU_USERUSED_DNODE(os) &&
1368 	    DMU_USERUSED_DNODE(os)->dn_type != DMU_OT_NONE) {
1369 		DMU_USERUSED_DNODE(os)->dn_zio = zio;
1370 		dnode_sync(DMU_USERUSED_DNODE(os), tx);
1371 		DMU_GROUPUSED_DNODE(os)->dn_zio = zio;
1372 		dnode_sync(DMU_GROUPUSED_DNODE(os), tx);
1373 	}
1374 
1375 	txgoff = tx->tx_txg & TXG_MASK;
1376 
1377 	if (dmu_objset_userused_enabled(os)) {
1378 		/*
1379 		 * We must create the list here because it uses the
1380 		 * dn_dirty_link[] of this txg.  But it may already
1381 		 * exist because we call dsl_dataset_sync() twice per txg.
1382 		 */
1383 		if (os->os_synced_dnodes == NULL) {
1384 			os->os_synced_dnodes =
1385 			    multilist_create(sizeof (dnode_t),
1386 			    offsetof(dnode_t, dn_dirty_link[txgoff]),
1387 			    dnode_multilist_index_func);
1388 		} else {
1389 			ASSERT3U(os->os_synced_dnodes->ml_offset, ==,
1390 			    offsetof(dnode_t, dn_dirty_link[txgoff]));
1391 		}
1392 	}
1393 
1394 	ml = os->os_dirty_dnodes[txgoff];
1395 	num_sublists = multilist_get_num_sublists(ml);
1396 	for (int i = 0; i < num_sublists; i++) {
1397 		if (multilist_sublist_is_empty_idx(ml, i))
1398 			continue;
1399 		sync_dnodes_arg_t *sda = kmem_alloc(sizeof (*sda), KM_SLEEP);
1400 		sda->sda_list = ml;
1401 		sda->sda_sublist_idx = i;
1402 		sda->sda_tx = tx;
1403 		(void) taskq_dispatch(dmu_objset_pool(os)->dp_sync_taskq,
1404 		    sync_dnodes_task, sda, 0);
1405 		/* callback frees sda */
1406 	}
1407 	taskq_wait(dmu_objset_pool(os)->dp_sync_taskq);
1408 
1409 	list = &DMU_META_DNODE(os)->dn_dirty_records[txgoff];
1410 	while ((dr = list_head(list)) != NULL) {
1411 		ASSERT0(dr->dr_dbuf->db_level);
1412 		list_remove(list, dr);
1413 		if (dr->dr_zio)
1414 			zio_nowait(dr->dr_zio);
1415 	}
1416 
1417 	/* Enable dnode backfill if enough objects have been freed. */
1418 	if (os->os_freed_dnodes >= dmu_rescan_dnode_threshold) {
1419 		os->os_rescan_dnodes = B_TRUE;
1420 		os->os_freed_dnodes = 0;
1421 	}
1422 
1423 	/*
1424 	 * Free intent log blocks up to this tx.
1425 	 */
1426 	zil_sync(os->os_zil, tx);
1427 	os->os_phys->os_zil_header = os->os_zil_header;
1428 	zio_nowait(zio);
1429 }
1430 
1431 boolean_t
dmu_objset_is_dirty(objset_t * os,uint64_t txg)1432 dmu_objset_is_dirty(objset_t *os, uint64_t txg)
1433 {
1434 	return (!multilist_is_empty(os->os_dirty_dnodes[txg & TXG_MASK]));
1435 }
1436 
1437 static objset_used_cb_t *used_cbs[DMU_OST_NUMTYPES];
1438 
1439 void
dmu_objset_register_type(dmu_objset_type_t ost,objset_used_cb_t * cb)1440 dmu_objset_register_type(dmu_objset_type_t ost, objset_used_cb_t *cb)
1441 {
1442 	used_cbs[ost] = cb;
1443 }
1444 
1445 boolean_t
dmu_objset_userused_enabled(objset_t * os)1446 dmu_objset_userused_enabled(objset_t *os)
1447 {
1448 	return (spa_version(os->os_spa) >= SPA_VERSION_USERSPACE &&
1449 	    used_cbs[os->os_phys->os_type] != NULL &&
1450 	    DMU_USERUSED_DNODE(os) != NULL);
1451 }
1452 
1453 typedef struct userquota_node {
1454 	uint64_t uqn_id;
1455 	int64_t uqn_delta;
1456 	avl_node_t uqn_node;
1457 } userquota_node_t;
1458 
1459 typedef struct userquota_cache {
1460 	avl_tree_t uqc_user_deltas;
1461 	avl_tree_t uqc_group_deltas;
1462 } userquota_cache_t;
1463 
1464 static int
userquota_compare(const void * l,const void * r)1465 userquota_compare(const void *l, const void *r)
1466 {
1467 	const userquota_node_t *luqn = l;
1468 	const userquota_node_t *ruqn = r;
1469 
1470 	if (luqn->uqn_id < ruqn->uqn_id)
1471 		return (-1);
1472 	if (luqn->uqn_id > ruqn->uqn_id)
1473 		return (1);
1474 	return (0);
1475 }
1476 
1477 static void
do_userquota_cacheflush(objset_t * os,userquota_cache_t * cache,dmu_tx_t * tx)1478 do_userquota_cacheflush(objset_t *os, userquota_cache_t *cache, dmu_tx_t *tx)
1479 {
1480 	void *cookie;
1481 	userquota_node_t *uqn;
1482 
1483 	ASSERT(dmu_tx_is_syncing(tx));
1484 
1485 	cookie = NULL;
1486 	while ((uqn = avl_destroy_nodes(&cache->uqc_user_deltas,
1487 	    &cookie)) != NULL) {
1488 		/*
1489 		 * os_userused_lock protects against concurrent calls to
1490 		 * zap_increment_int().  It's needed because zap_increment_int()
1491 		 * is not thread-safe (i.e. not atomic).
1492 		 */
1493 		mutex_enter(&os->os_userused_lock);
1494 		VERIFY0(zap_increment_int(os, DMU_USERUSED_OBJECT,
1495 		    uqn->uqn_id, uqn->uqn_delta, tx));
1496 		mutex_exit(&os->os_userused_lock);
1497 		kmem_free(uqn, sizeof (*uqn));
1498 	}
1499 	avl_destroy(&cache->uqc_user_deltas);
1500 
1501 	cookie = NULL;
1502 	while ((uqn = avl_destroy_nodes(&cache->uqc_group_deltas,
1503 	    &cookie)) != NULL) {
1504 		mutex_enter(&os->os_userused_lock);
1505 		VERIFY0(zap_increment_int(os, DMU_GROUPUSED_OBJECT,
1506 		    uqn->uqn_id, uqn->uqn_delta, tx));
1507 		mutex_exit(&os->os_userused_lock);
1508 		kmem_free(uqn, sizeof (*uqn));
1509 	}
1510 	avl_destroy(&cache->uqc_group_deltas);
1511 }
1512 
1513 static void
userquota_update_cache(avl_tree_t * avl,uint64_t id,int64_t delta)1514 userquota_update_cache(avl_tree_t *avl, uint64_t id, int64_t delta)
1515 {
1516 	userquota_node_t search = { .uqn_id = id };
1517 	avl_index_t idx;
1518 
1519 	userquota_node_t *uqn = avl_find(avl, &search, &idx);
1520 	if (uqn == NULL) {
1521 		uqn = kmem_zalloc(sizeof (*uqn), KM_SLEEP);
1522 		uqn->uqn_id = id;
1523 		avl_insert(avl, uqn, idx);
1524 	}
1525 	uqn->uqn_delta += delta;
1526 }
1527 
1528 static void
do_userquota_update(userquota_cache_t * cache,uint64_t used,uint64_t flags,uint64_t user,uint64_t group,boolean_t subtract)1529 do_userquota_update(userquota_cache_t *cache, uint64_t used, uint64_t flags,
1530     uint64_t user, uint64_t group, boolean_t subtract)
1531 {
1532 	if ((flags & DNODE_FLAG_USERUSED_ACCOUNTED)) {
1533 		int64_t delta = DNODE_SIZE + used;
1534 		if (subtract)
1535 			delta = -delta;
1536 
1537 		userquota_update_cache(&cache->uqc_user_deltas, user, delta);
1538 		userquota_update_cache(&cache->uqc_group_deltas, group, delta);
1539 	}
1540 }
1541 
1542 typedef struct userquota_updates_arg {
1543 	objset_t *uua_os;
1544 	int uua_sublist_idx;
1545 	dmu_tx_t *uua_tx;
1546 } userquota_updates_arg_t;
1547 
1548 static void
userquota_updates_task(void * arg)1549 userquota_updates_task(void *arg)
1550 {
1551 	userquota_updates_arg_t *uua = arg;
1552 	objset_t *os = uua->uua_os;
1553 	dmu_tx_t *tx = uua->uua_tx;
1554 	dnode_t *dn;
1555 	userquota_cache_t cache = { 0 };
1556 
1557 	multilist_sublist_t *list =
1558 	    multilist_sublist_lock(os->os_synced_dnodes, uua->uua_sublist_idx);
1559 
1560 	ASSERT(multilist_sublist_head(list) == NULL ||
1561 	    dmu_objset_userused_enabled(os));
1562 	avl_create(&cache.uqc_user_deltas, userquota_compare,
1563 	    sizeof (userquota_node_t), offsetof(userquota_node_t, uqn_node));
1564 	avl_create(&cache.uqc_group_deltas, userquota_compare,
1565 	    sizeof (userquota_node_t), offsetof(userquota_node_t, uqn_node));
1566 
1567 	while ((dn = multilist_sublist_head(list)) != NULL) {
1568 		int flags;
1569 		ASSERT(!DMU_OBJECT_IS_SPECIAL(dn->dn_object));
1570 		ASSERT(dn->dn_phys->dn_type == DMU_OT_NONE ||
1571 		    dn->dn_phys->dn_flags &
1572 		    DNODE_FLAG_USERUSED_ACCOUNTED);
1573 
1574 		flags = dn->dn_id_flags;
1575 		ASSERT(flags);
1576 		if (flags & DN_ID_OLD_EXIST)  {
1577 			do_userquota_update(&cache,
1578 			    dn->dn_oldused, dn->dn_oldflags,
1579 			    dn->dn_olduid, dn->dn_oldgid, B_TRUE);
1580 		}
1581 		if (flags & DN_ID_NEW_EXIST) {
1582 			do_userquota_update(&cache,
1583 			    DN_USED_BYTES(dn->dn_phys),
1584 			    dn->dn_phys->dn_flags,  dn->dn_newuid,
1585 			    dn->dn_newgid, B_FALSE);
1586 		}
1587 
1588 		mutex_enter(&dn->dn_mtx);
1589 		dn->dn_oldused = 0;
1590 		dn->dn_oldflags = 0;
1591 		if (dn->dn_id_flags & DN_ID_NEW_EXIST) {
1592 			dn->dn_olduid = dn->dn_newuid;
1593 			dn->dn_oldgid = dn->dn_newgid;
1594 			dn->dn_id_flags |= DN_ID_OLD_EXIST;
1595 			if (dn->dn_bonuslen == 0)
1596 				dn->dn_id_flags |= DN_ID_CHKED_SPILL;
1597 			else
1598 				dn->dn_id_flags |= DN_ID_CHKED_BONUS;
1599 		}
1600 		dn->dn_id_flags &= ~(DN_ID_NEW_EXIST);
1601 		mutex_exit(&dn->dn_mtx);
1602 
1603 		multilist_sublist_remove(list, dn);
1604 		dnode_rele(dn, os->os_synced_dnodes);
1605 	}
1606 	do_userquota_cacheflush(os, &cache, tx);
1607 	multilist_sublist_unlock(list);
1608 	kmem_free(uua, sizeof (*uua));
1609 }
1610 
1611 void
dmu_objset_do_userquota_updates(objset_t * os,dmu_tx_t * tx)1612 dmu_objset_do_userquota_updates(objset_t *os, dmu_tx_t *tx)
1613 {
1614 	int num_sublists;
1615 
1616 	if (!dmu_objset_userused_enabled(os))
1617 		return;
1618 
1619 	/* Allocate the user/groupused objects if necessary. */
1620 	if (DMU_USERUSED_DNODE(os)->dn_type == DMU_OT_NONE) {
1621 		VERIFY0(zap_create_claim(os,
1622 		    DMU_USERUSED_OBJECT,
1623 		    DMU_OT_USERGROUP_USED, DMU_OT_NONE, 0, tx));
1624 		VERIFY0(zap_create_claim(os,
1625 		    DMU_GROUPUSED_OBJECT,
1626 		    DMU_OT_USERGROUP_USED, DMU_OT_NONE, 0, tx));
1627 	}
1628 
1629 	num_sublists = multilist_get_num_sublists(os->os_synced_dnodes);
1630 	for (int i = 0; i < num_sublists; i++) {
1631 		if (multilist_sublist_is_empty_idx(os->os_synced_dnodes, i))
1632 			continue;
1633 		userquota_updates_arg_t *uua =
1634 		    kmem_alloc(sizeof (*uua), KM_SLEEP);
1635 		uua->uua_os = os;
1636 		uua->uua_sublist_idx = i;
1637 		uua->uua_tx = tx;
1638 		/* note: caller does taskq_wait() */
1639 		(void) taskq_dispatch(dmu_objset_pool(os)->dp_sync_taskq,
1640 		    userquota_updates_task, uua, 0);
1641 		/* callback frees uua */
1642 	}
1643 }
1644 
1645 /*
1646  * Returns a pointer to data to find uid/gid from
1647  *
1648  * If a dirty record for transaction group that is syncing can't
1649  * be found then NULL is returned.  In the NULL case it is assumed
1650  * the uid/gid aren't changing.
1651  */
1652 static void *
dmu_objset_userquota_find_data(dmu_buf_impl_t * db,dmu_tx_t * tx)1653 dmu_objset_userquota_find_data(dmu_buf_impl_t *db, dmu_tx_t *tx)
1654 {
1655 	dbuf_dirty_record_t *dr, **drp;
1656 	void *data;
1657 
1658 	if (db->db_dirtycnt == 0)
1659 		return (db->db.db_data);  /* Nothing is changing */
1660 
1661 	for (drp = &db->db_last_dirty; (dr = *drp) != NULL; drp = &dr->dr_next)
1662 		if (dr->dr_txg == tx->tx_txg)
1663 			break;
1664 
1665 	if (dr == NULL) {
1666 		data = NULL;
1667 	} else {
1668 		dnode_t *dn;
1669 
1670 		DB_DNODE_ENTER(dr->dr_dbuf);
1671 		dn = DB_DNODE(dr->dr_dbuf);
1672 
1673 		if (dn->dn_bonuslen == 0 &&
1674 		    dr->dr_dbuf->db_blkid == DMU_SPILL_BLKID)
1675 			data = dr->dt.dl.dr_data->b_data;
1676 		else
1677 			data = dr->dt.dl.dr_data;
1678 
1679 		DB_DNODE_EXIT(dr->dr_dbuf);
1680 	}
1681 
1682 	return (data);
1683 }
1684 
1685 void
dmu_objset_userquota_get_ids(dnode_t * dn,boolean_t before,dmu_tx_t * tx)1686 dmu_objset_userquota_get_ids(dnode_t *dn, boolean_t before, dmu_tx_t *tx)
1687 {
1688 	objset_t *os = dn->dn_objset;
1689 	void *data = NULL;
1690 	dmu_buf_impl_t *db = NULL;
1691 	uint64_t *user = NULL;
1692 	uint64_t *group = NULL;
1693 	int flags = dn->dn_id_flags;
1694 	int error;
1695 	boolean_t have_spill = B_FALSE;
1696 
1697 	if (!dmu_objset_userused_enabled(dn->dn_objset))
1698 		return;
1699 
1700 	if (before && (flags & (DN_ID_CHKED_BONUS|DN_ID_OLD_EXIST|
1701 	    DN_ID_CHKED_SPILL)))
1702 		return;
1703 
1704 	if (before && dn->dn_bonuslen != 0)
1705 		data = DN_BONUS(dn->dn_phys);
1706 	else if (!before && dn->dn_bonuslen != 0) {
1707 		if (dn->dn_bonus) {
1708 			db = dn->dn_bonus;
1709 			mutex_enter(&db->db_mtx);
1710 			data = dmu_objset_userquota_find_data(db, tx);
1711 		} else {
1712 			data = DN_BONUS(dn->dn_phys);
1713 		}
1714 	} else if (dn->dn_bonuslen == 0 && dn->dn_bonustype == DMU_OT_SA) {
1715 			int rf = 0;
1716 
1717 			if (RW_WRITE_HELD(&dn->dn_struct_rwlock))
1718 				rf |= DB_RF_HAVESTRUCT;
1719 			error = dmu_spill_hold_by_dnode(dn,
1720 			    rf | DB_RF_MUST_SUCCEED,
1721 			    FTAG, (dmu_buf_t **)&db);
1722 			ASSERT(error == 0);
1723 			mutex_enter(&db->db_mtx);
1724 			data = (before) ? db->db.db_data :
1725 			    dmu_objset_userquota_find_data(db, tx);
1726 			have_spill = B_TRUE;
1727 	} else {
1728 		mutex_enter(&dn->dn_mtx);
1729 		dn->dn_id_flags |= DN_ID_CHKED_BONUS;
1730 		mutex_exit(&dn->dn_mtx);
1731 		return;
1732 	}
1733 
1734 	if (before) {
1735 		ASSERT(data);
1736 		user = &dn->dn_olduid;
1737 		group = &dn->dn_oldgid;
1738 	} else if (data) {
1739 		user = &dn->dn_newuid;
1740 		group = &dn->dn_newgid;
1741 	}
1742 
1743 	/*
1744 	 * Must always call the callback in case the object
1745 	 * type has changed and that type isn't an object type to track
1746 	 */
1747 	error = used_cbs[os->os_phys->os_type](dn->dn_bonustype, data,
1748 	    user, group);
1749 
1750 	/*
1751 	 * Preserve existing uid/gid when the callback can't determine
1752 	 * what the new uid/gid are and the callback returned EEXIST.
1753 	 * The EEXIST error tells us to just use the existing uid/gid.
1754 	 * If we don't know what the old values are then just assign
1755 	 * them to 0, since that is a new file  being created.
1756 	 */
1757 	if (!before && data == NULL && error == EEXIST) {
1758 		if (flags & DN_ID_OLD_EXIST) {
1759 			dn->dn_newuid = dn->dn_olduid;
1760 			dn->dn_newgid = dn->dn_oldgid;
1761 		} else {
1762 			dn->dn_newuid = 0;
1763 			dn->dn_newgid = 0;
1764 		}
1765 		error = 0;
1766 	}
1767 
1768 	if (db)
1769 		mutex_exit(&db->db_mtx);
1770 
1771 	mutex_enter(&dn->dn_mtx);
1772 	if (error == 0 && before)
1773 		dn->dn_id_flags |= DN_ID_OLD_EXIST;
1774 	if (error == 0 && !before)
1775 		dn->dn_id_flags |= DN_ID_NEW_EXIST;
1776 
1777 	if (have_spill) {
1778 		dn->dn_id_flags |= DN_ID_CHKED_SPILL;
1779 	} else {
1780 		dn->dn_id_flags |= DN_ID_CHKED_BONUS;
1781 	}
1782 	mutex_exit(&dn->dn_mtx);
1783 	if (have_spill)
1784 		dmu_buf_rele((dmu_buf_t *)db, FTAG);
1785 }
1786 
1787 boolean_t
dmu_objset_userspace_present(objset_t * os)1788 dmu_objset_userspace_present(objset_t *os)
1789 {
1790 	return (os->os_phys->os_flags &
1791 	    OBJSET_FLAG_USERACCOUNTING_COMPLETE);
1792 }
1793 
1794 int
dmu_objset_userspace_upgrade(objset_t * os)1795 dmu_objset_userspace_upgrade(objset_t *os)
1796 {
1797 	uint64_t obj;
1798 	int err = 0;
1799 
1800 	if (dmu_objset_userspace_present(os))
1801 		return (0);
1802 	if (!dmu_objset_userused_enabled(os))
1803 		return (SET_ERROR(ENOTSUP));
1804 	if (dmu_objset_is_snapshot(os))
1805 		return (SET_ERROR(EINVAL));
1806 
1807 	/*
1808 	 * We simply need to mark every object dirty, so that it will be
1809 	 * synced out and now accounted.  If this is called
1810 	 * concurrently, or if we already did some work before crashing,
1811 	 * that's fine, since we track each object's accounted state
1812 	 * independently.
1813 	 */
1814 
1815 	for (obj = 0; err == 0; err = dmu_object_next(os, &obj, FALSE, 0)) {
1816 		dmu_tx_t *tx;
1817 		dmu_buf_t *db;
1818 		int objerr;
1819 
1820 		if (issig(JUSTLOOKING) && issig(FORREAL))
1821 			return (SET_ERROR(EINTR));
1822 
1823 		objerr = dmu_bonus_hold(os, obj, FTAG, &db);
1824 		if (objerr != 0)
1825 			continue;
1826 		tx = dmu_tx_create(os);
1827 		dmu_tx_hold_bonus(tx, obj);
1828 		objerr = dmu_tx_assign(tx, TXG_WAIT);
1829 		if (objerr != 0) {
1830 			dmu_tx_abort(tx);
1831 			continue;
1832 		}
1833 		dmu_buf_will_dirty(db, tx);
1834 		dmu_buf_rele(db, FTAG);
1835 		dmu_tx_commit(tx);
1836 	}
1837 
1838 	os->os_flags |= OBJSET_FLAG_USERACCOUNTING_COMPLETE;
1839 	txg_wait_synced(dmu_objset_pool(os), 0);
1840 	return (0);
1841 }
1842 
1843 void
dmu_objset_space(objset_t * os,uint64_t * refdbytesp,uint64_t * availbytesp,uint64_t * usedobjsp,uint64_t * availobjsp)1844 dmu_objset_space(objset_t *os, uint64_t *refdbytesp, uint64_t *availbytesp,
1845     uint64_t *usedobjsp, uint64_t *availobjsp)
1846 {
1847 	dsl_dataset_space(os->os_dsl_dataset, refdbytesp, availbytesp,
1848 	    usedobjsp, availobjsp);
1849 }
1850 
1851 uint64_t
dmu_objset_fsid_guid(objset_t * os)1852 dmu_objset_fsid_guid(objset_t *os)
1853 {
1854 	return (dsl_dataset_fsid_guid(os->os_dsl_dataset));
1855 }
1856 
1857 void
dmu_objset_fast_stat(objset_t * os,dmu_objset_stats_t * stat)1858 dmu_objset_fast_stat(objset_t *os, dmu_objset_stats_t *stat)
1859 {
1860 	stat->dds_type = os->os_phys->os_type;
1861 	if (os->os_dsl_dataset)
1862 		dsl_dataset_fast_stat(os->os_dsl_dataset, stat);
1863 }
1864 
1865 void
dmu_objset_stats(objset_t * os,nvlist_t * nv)1866 dmu_objset_stats(objset_t *os, nvlist_t *nv)
1867 {
1868 	ASSERT(os->os_dsl_dataset ||
1869 	    os->os_phys->os_type == DMU_OST_META);
1870 
1871 	if (os->os_dsl_dataset != NULL)
1872 		dsl_dataset_stats(os->os_dsl_dataset, nv);
1873 
1874 	dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_TYPE,
1875 	    os->os_phys->os_type);
1876 	dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USERACCOUNTING,
1877 	    dmu_objset_userspace_present(os));
1878 }
1879 
1880 int
dmu_objset_is_snapshot(objset_t * os)1881 dmu_objset_is_snapshot(objset_t *os)
1882 {
1883 	if (os->os_dsl_dataset != NULL)
1884 		return (os->os_dsl_dataset->ds_is_snapshot);
1885 	else
1886 		return (B_FALSE);
1887 }
1888 
1889 int
dmu_snapshot_realname(objset_t * os,char * name,char * real,int maxlen,boolean_t * conflict)1890 dmu_snapshot_realname(objset_t *os, char *name, char *real, int maxlen,
1891     boolean_t *conflict)
1892 {
1893 	dsl_dataset_t *ds = os->os_dsl_dataset;
1894 	uint64_t ignored;
1895 
1896 	if (dsl_dataset_phys(ds)->ds_snapnames_zapobj == 0)
1897 		return (SET_ERROR(ENOENT));
1898 
1899 	return (zap_lookup_norm(ds->ds_dir->dd_pool->dp_meta_objset,
1900 	    dsl_dataset_phys(ds)->ds_snapnames_zapobj, name, 8, 1, &ignored,
1901 	    MT_NORMALIZE, real, maxlen, conflict));
1902 }
1903 
1904 int
dmu_snapshot_list_next(objset_t * os,int namelen,char * name,uint64_t * idp,uint64_t * offp,boolean_t * case_conflict)1905 dmu_snapshot_list_next(objset_t *os, int namelen, char *name,
1906     uint64_t *idp, uint64_t *offp, boolean_t *case_conflict)
1907 {
1908 	dsl_dataset_t *ds = os->os_dsl_dataset;
1909 	zap_cursor_t cursor;
1910 	zap_attribute_t attr;
1911 
1912 	ASSERT(dsl_pool_config_held(dmu_objset_pool(os)));
1913 
1914 	if (dsl_dataset_phys(ds)->ds_snapnames_zapobj == 0)
1915 		return (SET_ERROR(ENOENT));
1916 
1917 	zap_cursor_init_serialized(&cursor,
1918 	    ds->ds_dir->dd_pool->dp_meta_objset,
1919 	    dsl_dataset_phys(ds)->ds_snapnames_zapobj, *offp);
1920 
1921 	if (zap_cursor_retrieve(&cursor, &attr) != 0) {
1922 		zap_cursor_fini(&cursor);
1923 		return (SET_ERROR(ENOENT));
1924 	}
1925 
1926 	if (strlen(attr.za_name) + 1 > namelen) {
1927 		zap_cursor_fini(&cursor);
1928 		return (SET_ERROR(ENAMETOOLONG));
1929 	}
1930 
1931 	(void) strcpy(name, attr.za_name);
1932 	if (idp)
1933 		*idp = attr.za_first_integer;
1934 	if (case_conflict)
1935 		*case_conflict = attr.za_normalization_conflict;
1936 	zap_cursor_advance(&cursor);
1937 	*offp = zap_cursor_serialize(&cursor);
1938 	zap_cursor_fini(&cursor);
1939 
1940 	return (0);
1941 }
1942 
1943 int
dmu_dir_list_next(objset_t * os,int namelen,char * name,uint64_t * idp,uint64_t * offp)1944 dmu_dir_list_next(objset_t *os, int namelen, char *name,
1945     uint64_t *idp, uint64_t *offp)
1946 {
1947 	dsl_dir_t *dd = os->os_dsl_dataset->ds_dir;
1948 	zap_cursor_t cursor;
1949 	zap_attribute_t attr;
1950 
1951 	/* there is no next dir on a snapshot! */
1952 	if (os->os_dsl_dataset->ds_object !=
1953 	    dsl_dir_phys(dd)->dd_head_dataset_obj)
1954 		return (SET_ERROR(ENOENT));
1955 
1956 	zap_cursor_init_serialized(&cursor,
1957 	    dd->dd_pool->dp_meta_objset,
1958 	    dsl_dir_phys(dd)->dd_child_dir_zapobj, *offp);
1959 
1960 	if (zap_cursor_retrieve(&cursor, &attr) != 0) {
1961 		zap_cursor_fini(&cursor);
1962 		return (SET_ERROR(ENOENT));
1963 	}
1964 
1965 	if (strlen(attr.za_name) + 1 > namelen) {
1966 		zap_cursor_fini(&cursor);
1967 		return (SET_ERROR(ENAMETOOLONG));
1968 	}
1969 
1970 	(void) strcpy(name, attr.za_name);
1971 	if (idp)
1972 		*idp = attr.za_first_integer;
1973 	zap_cursor_advance(&cursor);
1974 	*offp = zap_cursor_serialize(&cursor);
1975 	zap_cursor_fini(&cursor);
1976 
1977 	return (0);
1978 }
1979 
1980 typedef struct dmu_objset_find_ctx {
1981 	taskq_t		*dc_tq;
1982 	dsl_pool_t	*dc_dp;
1983 	uint64_t	dc_ddobj;
1984 	char		*dc_ddname; /* last component of ddobj's name */
1985 	int		(*dc_func)(dsl_pool_t *, dsl_dataset_t *, void *);
1986 	void		*dc_arg;
1987 	int		dc_flags;
1988 	kmutex_t	*dc_error_lock;
1989 	int		*dc_error;
1990 } dmu_objset_find_ctx_t;
1991 
1992 static void
dmu_objset_find_dp_impl(dmu_objset_find_ctx_t * dcp)1993 dmu_objset_find_dp_impl(dmu_objset_find_ctx_t *dcp)
1994 {
1995 	dsl_pool_t *dp = dcp->dc_dp;
1996 	dsl_dir_t *dd;
1997 	dsl_dataset_t *ds;
1998 	zap_cursor_t zc;
1999 	zap_attribute_t *attr;
2000 	uint64_t thisobj;
2001 	int err = 0;
2002 
2003 	/* don't process if there already was an error */
2004 	if (*dcp->dc_error != 0)
2005 		goto out;
2006 
2007 	/*
2008 	 * Note: passing the name (dc_ddname) here is optional, but it
2009 	 * improves performance because we don't need to call
2010 	 * zap_value_search() to determine the name.
2011 	 */
2012 	err = dsl_dir_hold_obj(dp, dcp->dc_ddobj, dcp->dc_ddname, FTAG, &dd);
2013 	if (err != 0)
2014 		goto out;
2015 
2016 	/* Don't visit hidden ($MOS & $ORIGIN) objsets. */
2017 	if (dd->dd_myname[0] == '$') {
2018 		dsl_dir_rele(dd, FTAG);
2019 		goto out;
2020 	}
2021 
2022 	thisobj = dsl_dir_phys(dd)->dd_head_dataset_obj;
2023 	attr = kmem_alloc(sizeof (zap_attribute_t), KM_SLEEP);
2024 
2025 	/*
2026 	 * Iterate over all children.
2027 	 */
2028 	if (dcp->dc_flags & DS_FIND_CHILDREN) {
2029 		for (zap_cursor_init(&zc, dp->dp_meta_objset,
2030 		    dsl_dir_phys(dd)->dd_child_dir_zapobj);
2031 		    zap_cursor_retrieve(&zc, attr) == 0;
2032 		    (void) zap_cursor_advance(&zc)) {
2033 			ASSERT3U(attr->za_integer_length, ==,
2034 			    sizeof (uint64_t));
2035 			ASSERT3U(attr->za_num_integers, ==, 1);
2036 
2037 			dmu_objset_find_ctx_t *child_dcp =
2038 			    kmem_alloc(sizeof (*child_dcp), KM_SLEEP);
2039 			*child_dcp = *dcp;
2040 			child_dcp->dc_ddobj = attr->za_first_integer;
2041 			child_dcp->dc_ddname = spa_strdup(attr->za_name);
2042 			if (dcp->dc_tq != NULL)
2043 				(void) taskq_dispatch(dcp->dc_tq,
2044 				    dmu_objset_find_dp_cb, child_dcp, TQ_SLEEP);
2045 			else
2046 				dmu_objset_find_dp_impl(child_dcp);
2047 		}
2048 		zap_cursor_fini(&zc);
2049 	}
2050 
2051 	/*
2052 	 * Iterate over all snapshots.
2053 	 */
2054 	if (dcp->dc_flags & DS_FIND_SNAPSHOTS) {
2055 		dsl_dataset_t *ds;
2056 		err = dsl_dataset_hold_obj(dp, thisobj, FTAG, &ds);
2057 
2058 		if (err == 0) {
2059 			uint64_t snapobj;
2060 
2061 			snapobj = dsl_dataset_phys(ds)->ds_snapnames_zapobj;
2062 			dsl_dataset_rele(ds, FTAG);
2063 
2064 			for (zap_cursor_init(&zc, dp->dp_meta_objset, snapobj);
2065 			    zap_cursor_retrieve(&zc, attr) == 0;
2066 			    (void) zap_cursor_advance(&zc)) {
2067 				ASSERT3U(attr->za_integer_length, ==,
2068 				    sizeof (uint64_t));
2069 				ASSERT3U(attr->za_num_integers, ==, 1);
2070 
2071 				err = dsl_dataset_hold_obj(dp,
2072 				    attr->za_first_integer, FTAG, &ds);
2073 				if (err != 0)
2074 					break;
2075 				err = dcp->dc_func(dp, ds, dcp->dc_arg);
2076 				dsl_dataset_rele(ds, FTAG);
2077 				if (err != 0)
2078 					break;
2079 			}
2080 			zap_cursor_fini(&zc);
2081 		}
2082 	}
2083 
2084 	kmem_free(attr, sizeof (zap_attribute_t));
2085 
2086 	if (err != 0) {
2087 		dsl_dir_rele(dd, FTAG);
2088 		goto out;
2089 	}
2090 
2091 	/*
2092 	 * Apply to self.
2093 	 */
2094 	err = dsl_dataset_hold_obj(dp, thisobj, FTAG, &ds);
2095 
2096 	/*
2097 	 * Note: we hold the dir while calling dsl_dataset_hold_obj() so
2098 	 * that the dir will remain cached, and we won't have to re-instantiate
2099 	 * it (which could be expensive due to finding its name via
2100 	 * zap_value_search()).
2101 	 */
2102 	dsl_dir_rele(dd, FTAG);
2103 	if (err != 0)
2104 		goto out;
2105 	err = dcp->dc_func(dp, ds, dcp->dc_arg);
2106 	dsl_dataset_rele(ds, FTAG);
2107 
2108 out:
2109 	if (err != 0) {
2110 		mutex_enter(dcp->dc_error_lock);
2111 		/* only keep first error */
2112 		if (*dcp->dc_error == 0)
2113 			*dcp->dc_error = err;
2114 		mutex_exit(dcp->dc_error_lock);
2115 	}
2116 
2117 	if (dcp->dc_ddname != NULL)
2118 		spa_strfree(dcp->dc_ddname);
2119 	kmem_free(dcp, sizeof (*dcp));
2120 }
2121 
2122 static void
dmu_objset_find_dp_cb(void * arg)2123 dmu_objset_find_dp_cb(void *arg)
2124 {
2125 	dmu_objset_find_ctx_t *dcp = arg;
2126 	dsl_pool_t *dp = dcp->dc_dp;
2127 
2128 	/*
2129 	 * We need to get a pool_config_lock here, as there are several
2130 	 * asssert(pool_config_held) down the stack. Getting a lock via
2131 	 * dsl_pool_config_enter is risky, as it might be stalled by a
2132 	 * pending writer. This would deadlock, as the write lock can
2133 	 * only be granted when our parent thread gives up the lock.
2134 	 * The _prio interface gives us priority over a pending writer.
2135 	 */
2136 	dsl_pool_config_enter_prio(dp, FTAG);
2137 
2138 	dmu_objset_find_dp_impl(dcp);
2139 
2140 	dsl_pool_config_exit(dp, FTAG);
2141 }
2142 
2143 /*
2144  * Find objsets under and including ddobj, call func(ds) on each.
2145  * The order for the enumeration is completely undefined.
2146  * func is called with dsl_pool_config held.
2147  */
2148 int
dmu_objset_find_dp(dsl_pool_t * dp,uint64_t ddobj,int func (dsl_pool_t *,dsl_dataset_t *,void *),void * arg,int flags)2149 dmu_objset_find_dp(dsl_pool_t *dp, uint64_t ddobj,
2150     int func(dsl_pool_t *, dsl_dataset_t *, void *), void *arg, int flags)
2151 {
2152 	int error = 0;
2153 	taskq_t *tq = NULL;
2154 	int ntasks;
2155 	dmu_objset_find_ctx_t *dcp;
2156 	kmutex_t err_lock;
2157 
2158 	mutex_init(&err_lock, NULL, MUTEX_DEFAULT, NULL);
2159 	dcp = kmem_alloc(sizeof (*dcp), KM_SLEEP);
2160 	dcp->dc_tq = NULL;
2161 	dcp->dc_dp = dp;
2162 	dcp->dc_ddobj = ddobj;
2163 	dcp->dc_ddname = NULL;
2164 	dcp->dc_func = func;
2165 	dcp->dc_arg = arg;
2166 	dcp->dc_flags = flags;
2167 	dcp->dc_error_lock = &err_lock;
2168 	dcp->dc_error = &error;
2169 
2170 	if ((flags & DS_FIND_SERIALIZE) || dsl_pool_config_held_writer(dp)) {
2171 		/*
2172 		 * In case a write lock is held we can't make use of
2173 		 * parallelism, as down the stack of the worker threads
2174 		 * the lock is asserted via dsl_pool_config_held.
2175 		 * In case of a read lock this is solved by getting a read
2176 		 * lock in each worker thread, which isn't possible in case
2177 		 * of a writer lock. So we fall back to the synchronous path
2178 		 * here.
2179 		 * In the future it might be possible to get some magic into
2180 		 * dsl_pool_config_held in a way that it returns true for
2181 		 * the worker threads so that a single lock held from this
2182 		 * thread suffices. For now, stay single threaded.
2183 		 */
2184 		dmu_objset_find_dp_impl(dcp);
2185 		mutex_destroy(&err_lock);
2186 
2187 		return (error);
2188 	}
2189 
2190 	ntasks = dmu_find_threads;
2191 	if (ntasks == 0)
2192 		ntasks = vdev_count_leaves(dp->dp_spa) * 4;
2193 	tq = taskq_create("dmu_objset_find", ntasks, minclsyspri, ntasks,
2194 	    INT_MAX, 0);
2195 	if (tq == NULL) {
2196 		kmem_free(dcp, sizeof (*dcp));
2197 		mutex_destroy(&err_lock);
2198 
2199 		return (SET_ERROR(ENOMEM));
2200 	}
2201 	dcp->dc_tq = tq;
2202 
2203 	/* dcp will be freed by task */
2204 	(void) taskq_dispatch(tq, dmu_objset_find_dp_cb, dcp, TQ_SLEEP);
2205 
2206 	/*
2207 	 * PORTING: this code relies on the property of taskq_wait to wait
2208 	 * until no more tasks are queued and no more tasks are active. As
2209 	 * we always queue new tasks from within other tasks, task_wait
2210 	 * reliably waits for the full recursion to finish, even though we
2211 	 * enqueue new tasks after taskq_wait has been called.
2212 	 * On platforms other than illumos, taskq_wait may not have this
2213 	 * property.
2214 	 */
2215 	taskq_wait(tq);
2216 	taskq_destroy(tq);
2217 	mutex_destroy(&err_lock);
2218 
2219 	return (error);
2220 }
2221 
2222 /*
2223  * Find all objsets under name, and for each, call 'func(child_name, arg)'.
2224  * The dp_config_rwlock must not be held when this is called, and it
2225  * will not be held when the callback is called.
2226  * Therefore this function should only be used when the pool is not changing
2227  * (e.g. in syncing context), or the callback can deal with the possible races.
2228  */
2229 static int
dmu_objset_find_impl(spa_t * spa,const char * name,int func (const char *,void *),void * arg,int flags)2230 dmu_objset_find_impl(spa_t *spa, const char *name,
2231     int func(const char *, void *), void *arg, int flags)
2232 {
2233 	dsl_dir_t *dd;
2234 	dsl_pool_t *dp = spa_get_dsl(spa);
2235 	dsl_dataset_t *ds;
2236 	zap_cursor_t zc;
2237 	zap_attribute_t *attr;
2238 	char *child;
2239 	uint64_t thisobj;
2240 	int err;
2241 
2242 	dsl_pool_config_enter(dp, FTAG);
2243 
2244 	err = dsl_dir_hold(dp, name, FTAG, &dd, NULL);
2245 	if (err != 0) {
2246 		dsl_pool_config_exit(dp, FTAG);
2247 		return (err);
2248 	}
2249 
2250 	/* Don't visit hidden ($MOS & $ORIGIN) objsets. */
2251 	if (dd->dd_myname[0] == '$') {
2252 		dsl_dir_rele(dd, FTAG);
2253 		dsl_pool_config_exit(dp, FTAG);
2254 		return (0);
2255 	}
2256 
2257 	thisobj = dsl_dir_phys(dd)->dd_head_dataset_obj;
2258 	attr = kmem_alloc(sizeof (zap_attribute_t), KM_SLEEP);
2259 
2260 	/*
2261 	 * Iterate over all children.
2262 	 */
2263 	if (flags & DS_FIND_CHILDREN) {
2264 		for (zap_cursor_init(&zc, dp->dp_meta_objset,
2265 		    dsl_dir_phys(dd)->dd_child_dir_zapobj);
2266 		    zap_cursor_retrieve(&zc, attr) == 0;
2267 		    (void) zap_cursor_advance(&zc)) {
2268 			ASSERT3U(attr->za_integer_length, ==,
2269 			    sizeof (uint64_t));
2270 			ASSERT3U(attr->za_num_integers, ==, 1);
2271 
2272 			child = kmem_asprintf("%s/%s", name, attr->za_name);
2273 			dsl_pool_config_exit(dp, FTAG);
2274 			err = dmu_objset_find_impl(spa, child,
2275 			    func, arg, flags);
2276 			dsl_pool_config_enter(dp, FTAG);
2277 			strfree(child);
2278 			if (err != 0)
2279 				break;
2280 		}
2281 		zap_cursor_fini(&zc);
2282 
2283 		if (err != 0) {
2284 			dsl_dir_rele(dd, FTAG);
2285 			dsl_pool_config_exit(dp, FTAG);
2286 			kmem_free(attr, sizeof (zap_attribute_t));
2287 			return (err);
2288 		}
2289 	}
2290 
2291 	/*
2292 	 * Iterate over all snapshots.
2293 	 */
2294 	if (flags & DS_FIND_SNAPSHOTS) {
2295 		err = dsl_dataset_hold_obj(dp, thisobj, FTAG, &ds);
2296 
2297 		if (err == 0) {
2298 			uint64_t snapobj;
2299 
2300 			snapobj = dsl_dataset_phys(ds)->ds_snapnames_zapobj;
2301 			dsl_dataset_rele(ds, FTAG);
2302 
2303 			for (zap_cursor_init(&zc, dp->dp_meta_objset, snapobj);
2304 			    zap_cursor_retrieve(&zc, attr) == 0;
2305 			    (void) zap_cursor_advance(&zc)) {
2306 				ASSERT3U(attr->za_integer_length, ==,
2307 				    sizeof (uint64_t));
2308 				ASSERT3U(attr->za_num_integers, ==, 1);
2309 
2310 				child = kmem_asprintf("%s@%s",
2311 				    name, attr->za_name);
2312 				dsl_pool_config_exit(dp, FTAG);
2313 				err = func(child, arg);
2314 				dsl_pool_config_enter(dp, FTAG);
2315 				strfree(child);
2316 				if (err != 0)
2317 					break;
2318 			}
2319 			zap_cursor_fini(&zc);
2320 		}
2321 	}
2322 
2323 	dsl_dir_rele(dd, FTAG);
2324 	kmem_free(attr, sizeof (zap_attribute_t));
2325 	dsl_pool_config_exit(dp, FTAG);
2326 
2327 	if (err != 0)
2328 		return (err);
2329 
2330 	/* Apply to self. */
2331 	return (func(name, arg));
2332 }
2333 
2334 /*
2335  * See comment above dmu_objset_find_impl().
2336  */
2337 int
dmu_objset_find(char * name,int func (const char *,void *),void * arg,int flags)2338 dmu_objset_find(char *name, int func(const char *, void *), void *arg,
2339     int flags)
2340 {
2341 	spa_t *spa;
2342 	int error;
2343 
2344 	error = spa_open(name, &spa, FTAG);
2345 	if (error != 0)
2346 		return (error);
2347 	error = dmu_objset_find_impl(spa, name, func, arg, flags);
2348 	spa_close(spa, FTAG);
2349 	return (error);
2350 }
2351 
2352 void
dmu_objset_set_user(objset_t * os,void * user_ptr)2353 dmu_objset_set_user(objset_t *os, void *user_ptr)
2354 {
2355 	ASSERT(MUTEX_HELD(&os->os_user_ptr_lock));
2356 	os->os_user_ptr = user_ptr;
2357 }
2358 
2359 void *
dmu_objset_get_user(objset_t * os)2360 dmu_objset_get_user(objset_t *os)
2361 {
2362 	ASSERT(MUTEX_HELD(&os->os_user_ptr_lock));
2363 	return (os->os_user_ptr);
2364 }
2365 
2366 /*
2367  * Determine name of filesystem, given name of snapshot.
2368  * buf must be at least ZFS_MAX_DATASET_NAME_LEN bytes
2369  */
2370 int
dmu_fsname(const char * snapname,char * buf)2371 dmu_fsname(const char *snapname, char *buf)
2372 {
2373 	char *atp = strchr(snapname, '@');
2374 	if (atp == NULL)
2375 		return (SET_ERROR(EINVAL));
2376 	if (atp - snapname >= ZFS_MAX_DATASET_NAME_LEN)
2377 		return (SET_ERROR(ENAMETOOLONG));
2378 	(void) strlcpy(buf, snapname, atp - snapname + 1);
2379 	return (0);
2380 }
2381 
2382 /*
2383  * Call when we think we're going to write/free space in open context to track
2384  * the amount of dirty data in the open txg, which is also the amount
2385  * of memory that can not be evicted until this txg syncs.
2386  */
2387 void
dmu_objset_willuse_space(objset_t * os,int64_t space,dmu_tx_t * tx)2388 dmu_objset_willuse_space(objset_t *os, int64_t space, dmu_tx_t *tx)
2389 {
2390 	dsl_dataset_t *ds = os->os_dsl_dataset;
2391 	int64_t aspace = spa_get_worst_case_asize(os->os_spa, space);
2392 
2393 	if (ds != NULL) {
2394 		dsl_dir_willuse_space(ds->ds_dir, aspace, tx);
2395 		dsl_pool_dirty_space(dmu_tx_pool(tx), space, tx);
2396 	}
2397 }
2398