Home | History | Annotate | Download | only in zfs
      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 2010 Sun Microsystems, Inc.  All rights reserved.
     23  * Use is subject to license terms.
     24  */
     25 
     26 #include <sys/cred.h>
     27 #include <sys/zfs_context.h>
     28 #include <sys/dmu_objset.h>
     29 #include <sys/dsl_dir.h>
     30 #include <sys/dsl_dataset.h>
     31 #include <sys/dsl_prop.h>
     32 #include <sys/dsl_pool.h>
     33 #include <sys/dsl_synctask.h>
     34 #include <sys/dsl_deleg.h>
     35 #include <sys/dnode.h>
     36 #include <sys/dbuf.h>
     37 #include <sys/zvol.h>
     38 #include <sys/dmu_tx.h>
     39 #include <sys/zap.h>
     40 #include <sys/zil.h>
     41 #include <sys/dmu_impl.h>
     42 #include <sys/zfs_ioctl.h>
     43 #include <sys/sunddi.h>
     44 
     45 spa_t *
     46 dmu_objset_spa(objset_t *os)
     47 {
     48 	return (os->os_spa);
     49 }
     50 
     51 zilog_t *
     52 dmu_objset_zil(objset_t *os)
     53 {
     54 	return (os->os_zil);
     55 }
     56 
     57 dsl_pool_t *
     58 dmu_objset_pool(objset_t *os)
     59 {
     60 	dsl_dataset_t *ds;
     61 
     62 	if ((ds = os->os_dsl_dataset) != NULL && ds->ds_dir)
     63 		return (ds->ds_dir->dd_pool);
     64 	else
     65 		return (spa_get_dsl(os->os_spa));
     66 }
     67 
     68 dsl_dataset_t *
     69 dmu_objset_ds(objset_t *os)
     70 {
     71 	return (os->os_dsl_dataset);
     72 }
     73 
     74 dmu_objset_type_t
     75 dmu_objset_type(objset_t *os)
     76 {
     77 	return (os->os_phys->os_type);
     78 }
     79 
     80 void
     81 dmu_objset_name(objset_t *os, char *buf)
     82 {
     83 	dsl_dataset_name(os->os_dsl_dataset, buf);
     84 }
     85 
     86 uint64_t
     87 dmu_objset_id(objset_t *os)
     88 {
     89 	dsl_dataset_t *ds = os->os_dsl_dataset;
     90 
     91 	return (ds ? ds->ds_object : 0);
     92 }
     93 
     94 uint64_t
     95 dmu_objset_logbias(objset_t *os)
     96 {
     97 	return (os->os_logbias);
     98 }
     99 
    100 static void
    101 checksum_changed_cb(void *arg, uint64_t newval)
    102 {
    103 	objset_t *os = arg;
    104 
    105 	/*
    106 	 * Inheritance should have been done by now.
    107 	 */
    108 	ASSERT(newval != ZIO_CHECKSUM_INHERIT);
    109 
    110 	os->os_checksum = zio_checksum_select(newval, ZIO_CHECKSUM_ON_VALUE);
    111 }
    112 
    113 static void
    114 compression_changed_cb(void *arg, uint64_t newval)
    115 {
    116 	objset_t *os = arg;
    117 
    118 	/*
    119 	 * Inheritance and range checking should have been done by now.
    120 	 */
    121 	ASSERT(newval != ZIO_COMPRESS_INHERIT);
    122 
    123 	os->os_compress = zio_compress_select(newval, ZIO_COMPRESS_ON_VALUE);
    124 }
    125 
    126 static void
    127 copies_changed_cb(void *arg, uint64_t newval)
    128 {
    129 	objset_t *os = arg;
    130 
    131 	/*
    132 	 * Inheritance and range checking should have been done by now.
    133 	 */
    134 	ASSERT(newval > 0);
    135 	ASSERT(newval <= spa_max_replication(os->os_spa));
    136 
    137 	os->os_copies = newval;
    138 }
    139 
    140 static void
    141 dedup_changed_cb(void *arg, uint64_t newval)
    142 {
    143 	objset_t *os = arg;
    144 	spa_t *spa = os->os_spa;
    145 	enum zio_checksum checksum;
    146 
    147 	/*
    148 	 * Inheritance should have been done by now.
    149 	 */
    150 	ASSERT(newval != ZIO_CHECKSUM_INHERIT);
    151 
    152 	checksum = zio_checksum_dedup_select(spa, newval, ZIO_CHECKSUM_OFF);
    153 
    154 	os->os_dedup_checksum = checksum & ZIO_CHECKSUM_MASK;
    155 	os->os_dedup_verify = !!(checksum & ZIO_CHECKSUM_VERIFY);
    156 }
    157 
    158 static void
    159 primary_cache_changed_cb(void *arg, uint64_t newval)
    160 {
    161 	objset_t *os = arg;
    162 
    163 	/*
    164 	 * Inheritance and range checking should have been done by now.
    165 	 */
    166 	ASSERT(newval == ZFS_CACHE_ALL || newval == ZFS_CACHE_NONE ||
    167 	    newval == ZFS_CACHE_METADATA);
    168 
    169 	os->os_primary_cache = newval;
    170 }
    171 
    172 static void
    173 secondary_cache_changed_cb(void *arg, uint64_t newval)
    174 {
    175 	objset_t *os = arg;
    176 
    177 	/*
    178 	 * Inheritance and range checking should have been done by now.
    179 	 */
    180 	ASSERT(newval == ZFS_CACHE_ALL || newval == ZFS_CACHE_NONE ||
    181 	    newval == ZFS_CACHE_METADATA);
    182 
    183 	os->os_secondary_cache = newval;
    184 }
    185 
    186 static void
    187 logbias_changed_cb(void *arg, uint64_t newval)
    188 {
    189 	objset_t *os = arg;
    190 
    191 	ASSERT(newval == ZFS_LOGBIAS_LATENCY ||
    192 	    newval == ZFS_LOGBIAS_THROUGHPUT);
    193 	os->os_logbias = newval;
    194 	if (os->os_zil)
    195 		zil_set_logbias(os->os_zil, newval);
    196 }
    197 
    198 void
    199 dmu_objset_byteswap(void *buf, size_t size)
    200 {
    201 	objset_phys_t *osp = buf;
    202 
    203 	ASSERT(size == OBJSET_OLD_PHYS_SIZE || size == sizeof (objset_phys_t));
    204 	dnode_byteswap(&osp->os_meta_dnode);
    205 	byteswap_uint64_array(&osp->os_zil_header, sizeof (zil_header_t));
    206 	osp->os_type = BSWAP_64(osp->os_type);
    207 	osp->os_flags = BSWAP_64(osp->os_flags);
    208 	if (size == sizeof (objset_phys_t)) {
    209 		dnode_byteswap(&osp->os_userused_dnode);
    210 		dnode_byteswap(&osp->os_groupused_dnode);
    211 	}
    212 }
    213 
    214 int
    215 dmu_objset_open_impl(spa_t *spa, dsl_dataset_t *ds, blkptr_t *bp,
    216     objset_t **osp)
    217 {
    218 	objset_t *os;
    219 	int i, err;
    220 
    221 	ASSERT(ds == NULL || MUTEX_HELD(&ds->ds_opening_lock));
    222 
    223 	os = kmem_zalloc(sizeof (objset_t), KM_SLEEP);
    224 	os->os_dsl_dataset = ds;
    225 	os->os_spa = spa;
    226 	os->os_rootbp = bp;
    227 	if (!BP_IS_HOLE(os->os_rootbp)) {
    228 		uint32_t aflags = ARC_WAIT;
    229 		zbookmark_t zb;
    230 		SET_BOOKMARK(&zb, ds ? ds->ds_object : DMU_META_OBJSET,
    231 		    ZB_ROOT_OBJECT, ZB_ROOT_LEVEL, ZB_ROOT_BLKID);
    232 
    233 		if (DMU_OS_IS_L2CACHEABLE(os))
    234 			aflags |= ARC_L2CACHE;
    235 
    236 		dprintf_bp(os->os_rootbp, "reading %s", "");
    237 		/*
    238 		 * NB: when bprewrite scrub can change the bp,
    239 		 * and this is called from dmu_objset_open_ds_os, the bp
    240 		 * could change, and we'll need a lock.
    241 		 */
    242 		err = arc_read_nolock(NULL, spa, os->os_rootbp,
    243 		    arc_getbuf_func, &os->os_phys_buf,
    244 		    ZIO_PRIORITY_SYNC_READ, ZIO_FLAG_CANFAIL, &aflags, &zb);
    245 		if (err) {
    246 			kmem_free(os, sizeof (objset_t));
    247 			/* convert checksum errors into IO errors */
    248 			if (err == ECKSUM)
    249 				err = EIO;
    250 			return (err);
    251 		}
    252 
    253 		/* Increase the blocksize if we are permitted. */
    254 		if (spa_version(spa) >= SPA_VERSION_USERSPACE &&
    255 		    arc_buf_size(os->os_phys_buf) < sizeof (objset_phys_t)) {
    256 			arc_buf_t *buf = arc_buf_alloc(spa,
    257 			    sizeof (objset_phys_t), &os->os_phys_buf,
    258 			    ARC_BUFC_METADATA);
    259 			bzero(buf->b_data, sizeof (objset_phys_t));
    260 			bcopy(os->os_phys_buf->b_data, buf->b_data,
    261 			    arc_buf_size(os->os_phys_buf));
    262 			(void) arc_buf_remove_ref(os->os_phys_buf,
    263 			    &os->os_phys_buf);
    264 			os->os_phys_buf = buf;
    265 		}
    266 
    267 		os->os_phys = os->os_phys_buf->b_data;
    268 		os->os_flags = os->os_phys->os_flags;
    269 	} else {
    270 		int size = spa_version(spa) >= SPA_VERSION_USERSPACE ?
    271 		    sizeof (objset_phys_t) : OBJSET_OLD_PHYS_SIZE;
    272 		os->os_phys_buf = arc_buf_alloc(spa, size,
    273 		    &os->os_phys_buf, ARC_BUFC_METADATA);
    274 		os->os_phys = os->os_phys_buf->b_data;
    275 		bzero(os->os_phys, size);
    276 	}
    277 
    278 	/*
    279 	 * Note: the changed_cb will be called once before the register
    280 	 * func returns, thus changing the checksum/compression from the
    281 	 * default (fletcher2/off).  Snapshots don't need to know about
    282 	 * checksum/compression/copies.
    283 	 */
    284 	if (ds) {
    285 		err = dsl_prop_register(ds, "primarycache",
    286 		    primary_cache_changed_cb, os);
    287 		if (err == 0)
    288 			err = dsl_prop_register(ds, "secondarycache",
    289 			    secondary_cache_changed_cb, os);
    290 		if (!dsl_dataset_is_snapshot(ds)) {
    291 			if (err == 0)
    292 				err = dsl_prop_register(ds, "checksum",
    293 				    checksum_changed_cb, os);
    294 			if (err == 0)
    295 				err = dsl_prop_register(ds, "compression",
    296 				    compression_changed_cb, os);
    297 			if (err == 0)
    298 				err = dsl_prop_register(ds, "copies",
    299 				    copies_changed_cb, os);
    300 			if (err == 0)
    301 				err = dsl_prop_register(ds, "dedup",
    302 				    dedup_changed_cb, os);
    303 			if (err == 0)
    304 				err = dsl_prop_register(ds, "logbias",
    305 				    logbias_changed_cb, os);
    306 		}
    307 		if (err) {
    308 			VERIFY(arc_buf_remove_ref(os->os_phys_buf,
    309 			    &os->os_phys_buf) == 1);
    310 			kmem_free(os, sizeof (objset_t));
    311 			return (err);
    312 		}
    313 	} else if (ds == NULL) {
    314 		/* It's the meta-objset. */
    315 		os->os_checksum = ZIO_CHECKSUM_FLETCHER_4;
    316 		os->os_compress = ZIO_COMPRESS_LZJB;
    317 		os->os_copies = spa_max_replication(spa);
    318 		os->os_dedup_checksum = ZIO_CHECKSUM_OFF;
    319 		os->os_dedup_verify = 0;
    320 		os->os_logbias = 0;
    321 		os->os_primary_cache = ZFS_CACHE_ALL;
    322 		os->os_secondary_cache = ZFS_CACHE_ALL;
    323 	}
    324 
    325 	os->os_zil_header = os->os_phys->os_zil_header;
    326 	os->os_zil = zil_alloc(os, &os->os_zil_header);
    327 
    328 	for (i = 0; i < TXG_SIZE; i++) {
    329 		list_create(&os->os_dirty_dnodes[i], sizeof (dnode_t),
    330 		    offsetof(dnode_t, dn_dirty_link[i]));
    331 		list_create(&os->os_free_dnodes[i], sizeof (dnode_t),
    332 		    offsetof(dnode_t, dn_dirty_link[i]));
    333 	}
    334 	list_create(&os->os_dnodes, sizeof (dnode_t),
    335 	    offsetof(dnode_t, dn_link));
    336 	list_create(&os->os_downgraded_dbufs, sizeof (dmu_buf_impl_t),
    337 	    offsetof(dmu_buf_impl_t, db_link));
    338 
    339 	mutex_init(&os->os_lock, NULL, MUTEX_DEFAULT, NULL);
    340 	mutex_init(&os->os_obj_lock, NULL, MUTEX_DEFAULT, NULL);
    341 	mutex_init(&os->os_user_ptr_lock, NULL, MUTEX_DEFAULT, NULL);
    342 
    343 	os->os_meta_dnode = dnode_special_open(os,
    344 	    &os->os_phys->os_meta_dnode, DMU_META_DNODE_OBJECT);
    345 	if (arc_buf_size(os->os_phys_buf) >= sizeof (objset_phys_t)) {
    346 		os->os_userused_dnode = dnode_special_open(os,
    347 		    &os->os_phys->os_userused_dnode, DMU_USERUSED_OBJECT);
    348 		os->os_groupused_dnode = dnode_special_open(os,
    349 		    &os->os_phys->os_groupused_dnode, DMU_GROUPUSED_OBJECT);
    350 	}
    351 
    352 	/*
    353 	 * We should be the only thread trying to do this because we
    354 	 * have ds_opening_lock
    355 	 */
    356 	if (ds) {
    357 		mutex_enter(&ds->ds_lock);
    358 		ASSERT(ds->ds_objset == NULL);
    359 		ds->ds_objset = os;
    360 		mutex_exit(&ds->ds_lock);
    361 	}
    362 
    363 	*osp = os;
    364 	return (0);
    365 }
    366 
    367 int
    368 dmu_objset_from_ds(dsl_dataset_t *ds, objset_t **osp)
    369 {
    370 	int err = 0;
    371 
    372 	mutex_enter(&ds->ds_opening_lock);
    373 	*osp = ds->ds_objset;
    374 	if (*osp == NULL) {
    375 		err = dmu_objset_open_impl(dsl_dataset_get_spa(ds),
    376 		    ds, &ds->ds_phys->ds_bp, osp);
    377 	}
    378 	mutex_exit(&ds->ds_opening_lock);
    379 	return (err);
    380 }
    381 
    382 /* called from zpl */
    383 int
    384 dmu_objset_hold(const char *name, void *tag, objset_t **osp)
    385 {
    386 	dsl_dataset_t *ds;
    387 	int err;
    388 
    389 	err = dsl_dataset_hold(name, tag, &ds);
    390 	if (err)
    391 		return (err);
    392 
    393 	err = dmu_objset_from_ds(ds, osp);
    394 	if (err)
    395 		dsl_dataset_rele(ds, tag);
    396 
    397 	return (err);
    398 }
    399 
    400 /* called from zpl */
    401 int
    402 dmu_objset_own(const char *name, dmu_objset_type_t type,
    403     boolean_t readonly, void *tag, objset_t **osp)
    404 {
    405 	dsl_dataset_t *ds;
    406 	int err;
    407 
    408 	err = dsl_dataset_own(name, B_FALSE, tag, &ds);
    409 	if (err)
    410 		return (err);
    411 
    412 	err = dmu_objset_from_ds(ds, osp);
    413 	if (err) {
    414 		dsl_dataset_disown(ds, tag);
    415 	} else if (type != DMU_OST_ANY && type != (*osp)->os_phys->os_type) {
    416 		dmu_objset_disown(*osp, tag);
    417 		return (EINVAL);
    418 	} else if (!readonly && dsl_dataset_is_snapshot(ds)) {
    419 		dmu_objset_disown(*osp, tag);
    420 		return (EROFS);
    421 	}
    422 	return (err);
    423 }
    424 
    425 void
    426 dmu_objset_rele(objset_t *os, void *tag)
    427 {
    428 	dsl_dataset_rele(os->os_dsl_dataset, tag);
    429 }
    430 
    431 void
    432 dmu_objset_disown(objset_t *os, void *tag)
    433 {
    434 	dsl_dataset_disown(os->os_dsl_dataset, tag);
    435 }
    436 
    437 int
    438 dmu_objset_evict_dbufs(objset_t *os)
    439 {
    440 	dnode_t *dn;
    441 
    442 	mutex_enter(&os->os_lock);
    443 
    444 	/* process the mdn last, since the other dnodes have holds on it */
    445 	list_remove(&os->os_dnodes, os->os_meta_dnode);
    446 	list_insert_tail(&os->os_dnodes, os->os_meta_dnode);
    447 
    448 	/*
    449 	 * Find the first dnode with holds.  We have to do this dance
    450 	 * because dnode_add_ref() only works if you already have a
    451 	 * hold.  If there are no holds then it has no dbufs so OK to
    452 	 * skip.
    453 	 */
    454 	for (dn = list_head(&os->os_dnodes);
    455 	    dn && !dnode_add_ref(dn, FTAG);
    456 	    dn = list_next(&os->os_dnodes, dn))
    457 		continue;
    458 
    459 	while (dn) {
    460 		dnode_t *next_dn = dn;
    461 
    462 		do {
    463 			next_dn = list_next(&os->os_dnodes, next_dn);
    464 		} while (next_dn && !dnode_add_ref(next_dn, FTAG));
    465 
    466 		mutex_exit(&os->os_lock);
    467 		dnode_evict_dbufs(dn);
    468 		dnode_rele(dn, FTAG);
    469 		mutex_enter(&os->os_lock);
    470 		dn = next_dn;
    471 	}
    472 	mutex_exit(&os->os_lock);
    473 	return (list_head(&os->os_dnodes) != os->os_meta_dnode);
    474 }
    475 
    476 void
    477 dmu_objset_evict(objset_t *os)
    478 {
    479 	dsl_dataset_t *ds = os->os_dsl_dataset;
    480 
    481 	for (int t = 0; t < TXG_SIZE; t++)
    482 		ASSERT(!dmu_objset_is_dirty(os, t));
    483 
    484 	if (ds) {
    485 		if (!dsl_dataset_is_snapshot(ds)) {
    486 			VERIFY(0 == dsl_prop_unregister(ds, "checksum",
    487 			    checksum_changed_cb, os));
    488 			VERIFY(0 == dsl_prop_unregister(ds, "compression",
    489 			    compression_changed_cb, os));
    490 			VERIFY(0 == dsl_prop_unregister(ds, "copies",
    491 			    copies_changed_cb, os));
    492 			VERIFY(0 == dsl_prop_unregister(ds, "dedup",
    493 			    dedup_changed_cb, os));
    494 			VERIFY(0 == dsl_prop_unregister(ds, "logbias",
    495 			    logbias_changed_cb, os));
    496 		}
    497 		VERIFY(0 == dsl_prop_unregister(ds, "primarycache",
    498 		    primary_cache_changed_cb, os));
    499 		VERIFY(0 == dsl_prop_unregister(ds, "secondarycache",
    500 		    secondary_cache_changed_cb, os));
    501 	}
    502 
    503 	/*
    504 	 * We should need only a single pass over the dnode list, since
    505 	 * nothing can be added to the list at this point.
    506 	 */
    507 	(void) dmu_objset_evict_dbufs(os);
    508 
    509 	dnode_special_close(os->os_meta_dnode);
    510 	if (os->os_userused_dnode) {
    511 		dnode_special_close(os->os_userused_dnode);
    512 		dnode_special_close(os->os_groupused_dnode);
    513 	}
    514 	zil_free(os->os_zil);
    515 
    516 	ASSERT3P(list_head(&os->os_dnodes), ==, NULL);
    517 
    518 	VERIFY(arc_buf_remove_ref(os->os_phys_buf, &os->os_phys_buf) == 1);
    519 	mutex_destroy(&os->os_lock);
    520 	mutex_destroy(&os->os_obj_lock);
    521 	mutex_destroy(&os->os_user_ptr_lock);
    522 	kmem_free(os, sizeof (objset_t));
    523 }
    524 
    525 timestruc_t
    526 dmu_objset_snap_cmtime(objset_t *os)
    527 {
    528 	return (dsl_dir_snap_cmtime(os->os_dsl_dataset->ds_dir));
    529 }
    530 
    531 /* called from dsl for meta-objset */
    532 objset_t *
    533 dmu_objset_create_impl(spa_t *spa, dsl_dataset_t *ds, blkptr_t *bp,
    534     dmu_objset_type_t type, dmu_tx_t *tx)
    535 {
    536 	objset_t *os;
    537 	dnode_t *mdn;
    538 
    539 	ASSERT(dmu_tx_is_syncing(tx));
    540 	if (ds)
    541 		mutex_enter(&ds->ds_opening_lock);
    542 	VERIFY(0 == dmu_objset_open_impl(spa, ds, bp, &os));
    543 	if (ds)
    544 		mutex_exit(&ds->ds_opening_lock);
    545 	mdn = os->os_meta_dnode;
    546 
    547 	dnode_allocate(mdn, DMU_OT_DNODE, 1 << DNODE_BLOCK_SHIFT,
    548 	    DN_MAX_INDBLKSHIFT, DMU_OT_NONE, 0, tx);
    549 
    550 	/*
    551 	 * We don't want to have to increase the meta-dnode's nlevels
    552 	 * later, because then we could do it in quescing context while
    553 	 * we are also accessing it in open context.
    554 	 *
    555 	 * This precaution is not necessary for the MOS (ds == NULL),
    556 	 * because the MOS is only updated in syncing context.
    557 	 * This is most fortunate: the MOS is the only objset that
    558 	 * needs to be synced multiple times as spa_sync() iterates
    559 	 * to convergence, so minimizing its dn_nlevels matters.
    560 	 */
    561 	if (ds != NULL) {
    562 		int levels = 1;
    563 
    564 		/*
    565 		 * Determine the number of levels necessary for the meta-dnode
    566 		 * to contain DN_MAX_OBJECT dnodes.
    567 		 */
    568 		while ((uint64_t)mdn->dn_nblkptr << (mdn->dn_datablkshift +
    569 		    (levels - 1) * (mdn->dn_indblkshift - SPA_BLKPTRSHIFT)) <
    570 		    DN_MAX_OBJECT * sizeof (dnode_phys_t))
    571 			levels++;
    572 
    573 		mdn->dn_next_nlevels[tx->tx_txg & TXG_MASK] =
    574 		    mdn->dn_nlevels = levels;
    575 	}
    576 
    577 	ASSERT(type != DMU_OST_NONE);
    578 	ASSERT(type != DMU_OST_ANY);
    579 	ASSERT(type < DMU_OST_NUMTYPES);
    580 	os->os_phys->os_type = type;
    581 	if (dmu_objset_userused_enabled(os)) {
    582 		os->os_phys->os_flags |= OBJSET_FLAG_USERACCOUNTING_COMPLETE;
    583 		os->os_flags = os->os_phys->os_flags;
    584 	}
    585 
    586 	dsl_dataset_dirty(ds, tx);
    587 
    588 	return (os);
    589 }
    590 
    591 struct oscarg {
    592 	void (*userfunc)(objset_t *os, void *arg, cred_t *cr, dmu_tx_t *tx);
    593 	void *userarg;
    594 	dsl_dataset_t *clone_origin;
    595 	const char *lastname;
    596 	dmu_objset_type_t type;
    597 	uint64_t flags;
    598 };
    599 
    600 /*ARGSUSED*/
    601 static int
    602 dmu_objset_create_check(void *arg1, void *arg2, dmu_tx_t *tx)
    603 {
    604 	dsl_dir_t *dd = arg1;
    605 	struct oscarg *oa = arg2;
    606 	objset_t *mos = dd->dd_pool->dp_meta_objset;
    607 	int err;
    608 	uint64_t ddobj;
    609 
    610 	err = zap_lookup(mos, dd->dd_phys->dd_child_dir_zapobj,
    611 	    oa->lastname, sizeof (uint64_t), 1, &ddobj);
    612 	if (err != ENOENT)
    613 		return (err ? err : EEXIST);
    614 
    615 	if (oa->clone_origin != NULL) {
    616 		/* You can't clone across pools. */
    617 		if (oa->clone_origin->ds_dir->dd_pool != dd->dd_pool)
    618 			return (EXDEV);
    619 
    620 		/* You can only clone snapshots, not the head datasets. */
    621 		if (!dsl_dataset_is_snapshot(oa->clone_origin))
    622 			return (EINVAL);
    623 	}
    624 
    625 	return (0);
    626 }
    627 
    628 static void
    629 dmu_objset_create_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx)
    630 {
    631 	dsl_dir_t *dd = arg1;
    632 	struct oscarg *oa = arg2;
    633 	uint64_t dsobj;
    634 
    635 	ASSERT(dmu_tx_is_syncing(tx));
    636 
    637 	dsobj = dsl_dataset_create_sync(dd, oa->lastname,
    638 	    oa->clone_origin, oa->flags, cr, tx);
    639 
    640 	if (oa->clone_origin == NULL) {
    641 		dsl_dataset_t *ds;
    642 		blkptr_t *bp;
    643 		objset_t *os;
    644 
    645 		VERIFY(0 == dsl_dataset_hold_obj(dd->dd_pool, dsobj,
    646 		    FTAG, &ds));
    647 		bp = dsl_dataset_get_blkptr(ds);
    648 		ASSERT(BP_IS_HOLE(bp));
    649 
    650 		os = dmu_objset_create_impl(dsl_dataset_get_spa(ds),
    651 		    ds, bp, oa->type, tx);
    652 
    653 		if (oa->userfunc)
    654 			oa->userfunc(os, oa->userarg, cr, tx);
    655 		dsl_dataset_rele(ds, FTAG);
    656 	}
    657 
    658 	spa_history_internal_log(LOG_DS_CREATE, dd->dd_pool->dp_spa,
    659 	    tx, cr, "dataset = %llu", dsobj);
    660 }
    661 
    662 int
    663 dmu_objset_create(const char *name, dmu_objset_type_t type, uint64_t flags,
    664     void (*func)(objset_t *os, void *arg, cred_t *cr, dmu_tx_t *tx), void *arg)
    665 {
    666 	dsl_dir_t *pdd;
    667 	const char *tail;
    668 	int err = 0;
    669 	struct oscarg oa = { 0 };
    670 
    671 	ASSERT(strchr(name, '@') == NULL);
    672 	err = dsl_dir_open(name, FTAG, &pdd, &tail);
    673 	if (err)
    674 		return (err);
    675 	if (tail == NULL) {
    676 		dsl_dir_close(pdd, FTAG);
    677 		return (EEXIST);
    678 	}
    679 
    680 	oa.userfunc = func;
    681 	oa.userarg = arg;
    682 	oa.lastname = tail;
    683 	oa.type = type;
    684 	oa.flags = flags;
    685 
    686 	err = dsl_sync_task_do(pdd->dd_pool, dmu_objset_create_check,
    687 	    dmu_objset_create_sync, pdd, &oa, 5);
    688 	dsl_dir_close(pdd, FTAG);
    689 	return (err);
    690 }
    691 
    692 int
    693 dmu_objset_clone(const char *name, dsl_dataset_t *clone_origin, uint64_t flags)
    694 {
    695 	dsl_dir_t *pdd;
    696 	const char *tail;
    697 	int err = 0;
    698 	struct oscarg oa = { 0 };
    699 
    700 	ASSERT(strchr(name, '@') == NULL);
    701 	err = dsl_dir_open(name, FTAG, &pdd, &tail);
    702 	if (err)
    703 		return (err);
    704 	if (tail == NULL) {
    705 		dsl_dir_close(pdd, FTAG);
    706 		return (EEXIST);
    707 	}
    708 
    709 	oa.lastname = tail;
    710 	oa.clone_origin = clone_origin;
    711 	oa.flags = flags;
    712 
    713 	err = dsl_sync_task_do(pdd->dd_pool, dmu_objset_create_check,
    714 	    dmu_objset_create_sync, pdd, &oa, 5);
    715 	dsl_dir_close(pdd, FTAG);
    716 	return (err);
    717 }
    718 
    719 int
    720 dmu_objset_destroy(const char *name, boolean_t defer)
    721 {
    722 	dsl_dataset_t *ds;
    723 	int error;
    724 
    725 	/*
    726 	 * dsl_dataset_destroy() can free any claimed-but-unplayed
    727 	 * intent log, but if there is an active log, it has blocks that
    728 	 * are allocated, but may not yet be reflected in the on-disk
    729 	 * structure.  Only the ZIL knows how to free them, so we have
    730 	 * to call into it here.
    731 	 */
    732 	error = dsl_dataset_own(name, B_TRUE, FTAG, &ds);
    733 	if (error == 0) {
    734 		objset_t *os;
    735 		if (dmu_objset_from_ds(ds, &os) == 0)
    736 			zil_destroy(dmu_objset_zil(os), B_FALSE);
    737 		error = dsl_dataset_destroy(ds, FTAG, defer);
    738 		/* dsl_dataset_destroy() closes the ds. */
    739 	}
    740 
    741 	return (error);
    742 }
    743 
    744 struct snaparg {
    745 	dsl_sync_task_group_t *dstg;
    746 	char *snapname;
    747 	char failed[MAXPATHLEN];
    748 	boolean_t recursive;
    749 	nvlist_t *props;
    750 };
    751 
    752 static int
    753 snapshot_check(void *arg1, void *arg2, dmu_tx_t *tx)
    754 {
    755 	objset_t *os = arg1;
    756 	struct snaparg *sn = arg2;
    757 
    758 	/* The props have already been checked by zfs_check_userprops(). */
    759 
    760 	return (dsl_dataset_snapshot_check(os->os_dsl_dataset,
    761 	    sn->snapname, tx));
    762 }
    763 
    764 static void
    765 snapshot_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx)
    766 {
    767 	objset_t *os = arg1;
    768 	dsl_dataset_t *ds = os->os_dsl_dataset;
    769 	struct snaparg *sn = arg2;
    770 
    771 	dsl_dataset_snapshot_sync(ds, sn->snapname, cr, tx);
    772 
    773 	if (sn->props) {
    774 		dsl_props_arg_t pa;
    775 		pa.pa_props = sn->props;
    776 		pa.pa_source = ZPROP_SRC_LOCAL;
    777 		dsl_props_set_sync(ds->ds_prev, &pa, cr, tx);
    778 	}
    779 }
    780 
    781 static int
    782 dmu_objset_snapshot_one(const char *name, void *arg)
    783 {
    784 	struct snaparg *sn = arg;
    785 	objset_t *os;
    786 	int err;
    787 	char *cp;
    788 
    789 	/*
    790 	 * If the objset starts with a '%', then ignore it unless it was
    791 	 * explicitly named (ie, not recursive).  These hidden datasets
    792 	 * are always inconsistent, and by not opening them here, we can
    793 	 * avoid a race with dsl_dir_destroy_check().
    794 	 */
    795 	cp = strrchr(name, '/');
    796 	if (cp && cp[1] == '%' && sn->recursive)
    797 		return (0);
    798 
    799 	(void) strcpy(sn->failed, name);
    800 
    801 	/*
    802 	 * Check permissions if we are doing a recursive snapshot.  The
    803 	 * permission checks for the starting dataset have already been
    804 	 * performed in zfs_secpolicy_snapshot()
    805 	 */
    806 	if (sn->recursive && (err = zfs_secpolicy_snapshot_perms(name, CRED())))
    807 		return (err);
    808 
    809 	err = dmu_objset_hold(name, sn, &os);
    810 	if (err != 0)
    811 		return (err);
    812 
    813 	/*
    814 	 * If the objset is in an inconsistent state (eg, in the process
    815 	 * of being destroyed), don't snapshot it.  As with %hidden
    816 	 * datasets, we return EBUSY if this name was explicitly
    817 	 * requested (ie, not recursive), and otherwise ignore it.
    818 	 */
    819 	if (os->os_dsl_dataset->ds_phys->ds_flags & DS_FLAG_INCONSISTENT) {
    820 		dmu_objset_rele(os, sn);
    821 		return (sn->recursive ? 0 : EBUSY);
    822 	}
    823 
    824 	/*
    825 	 * NB: we need to wait for all in-flight changes to get to disk,
    826 	 * so that we snapshot those changes.  zil_suspend does this as
    827 	 * a side effect.
    828 	 */
    829 	err = zil_suspend(dmu_objset_zil(os));
    830 	if (err == 0) {
    831 		dsl_sync_task_create(sn->dstg, snapshot_check,
    832 		    snapshot_sync, os, sn, 3);
    833 	} else {
    834 		dmu_objset_rele(os, sn);
    835 	}
    836 
    837 	return (err);
    838 }
    839 
    840 int
    841 dmu_objset_snapshot(char *fsname, char *snapname,
    842     nvlist_t *props, boolean_t recursive)
    843 {
    844 	dsl_sync_task_t *dst;
    845 	struct snaparg sn;
    846 	spa_t *spa;
    847 	int err;
    848 
    849 	(void) strcpy(sn.failed, fsname);
    850 
    851 	err = spa_open(fsname, &spa, FTAG);
    852 	if (err)
    853 		return (err);
    854 
    855 	sn.dstg = dsl_sync_task_group_create(spa_get_dsl(spa));
    856 	sn.snapname = snapname;
    857 	sn.props = props;
    858 	sn.recursive = recursive;
    859 
    860 	if (recursive) {
    861 		err = dmu_objset_find(fsname,
    862 		    dmu_objset_snapshot_one, &sn, DS_FIND_CHILDREN);
    863 	} else {
    864 		err = dmu_objset_snapshot_one(fsname, &sn);
    865 	}
    866 
    867 	if (err == 0)
    868 		err = dsl_sync_task_group_wait(sn.dstg);
    869 
    870 	for (dst = list_head(&sn.dstg->dstg_tasks); dst;
    871 	    dst = list_next(&sn.dstg->dstg_tasks, dst)) {
    872 		objset_t *os = dst->dst_arg1;
    873 		dsl_dataset_t *ds = os->os_dsl_dataset;
    874 		if (dst->dst_err)
    875 			dsl_dataset_name(ds, sn.failed);
    876 		zil_resume(dmu_objset_zil(os));
    877 		dmu_objset_rele(os, &sn);
    878 	}
    879 
    880 	if (err)
    881 		(void) strcpy(fsname, sn.failed);
    882 	dsl_sync_task_group_destroy(sn.dstg);
    883 	spa_close(spa, FTAG);
    884 	return (err);
    885 }
    886 
    887 static void
    888 dmu_objset_sync_dnodes(list_t *list, list_t *newlist, dmu_tx_t *tx)
    889 {
    890 	dnode_t *dn;
    891 
    892 	while (dn = list_head(list)) {
    893 		ASSERT(dn->dn_object != DMU_META_DNODE_OBJECT);
    894 		ASSERT(dn->dn_dbuf->db_data_pending);
    895 		/*
    896 		 * Initialize dn_zio outside dnode_sync() because the
    897 		 * meta-dnode needs to set it ouside dnode_sync().
    898 		 */
    899 		dn->dn_zio = dn->dn_dbuf->db_data_pending->dr_zio;
    900 		ASSERT(dn->dn_zio);
    901 
    902 		ASSERT3U(dn->dn_nlevels, <=, DN_MAX_LEVELS);
    903 		list_remove(list, dn);
    904 
    905 		if (newlist) {
    906 			(void) dnode_add_ref(dn, newlist);
    907 			list_insert_tail(newlist, dn);
    908 		}
    909 
    910 		dnode_sync(dn, tx);
    911 	}
    912 }
    913 
    914 /* ARGSUSED */
    915 static void
    916 dmu_objset_write_ready(zio_t *zio, arc_buf_t *abuf, void *arg)
    917 {
    918 	blkptr_t *bp = zio->io_bp;
    919 	objset_t *os = arg;
    920 	dnode_phys_t *dnp = &os->os_phys->os_meta_dnode;
    921 
    922 	ASSERT(bp == os->os_rootbp);
    923 	ASSERT(BP_GET_TYPE(bp) == DMU_OT_OBJSET);
    924 	ASSERT(BP_GET_LEVEL(bp) == 0);
    925 
    926 	/*
    927 	 * Update rootbp fill count: it should be the number of objects
    928 	 * allocated in the object set (not counting the "special"
    929 	 * objects that are stored in the objset_phys_t -- the meta
    930 	 * dnode and user/group accounting objects).
    931 	 */
    932 	bp->blk_fill = 0;
    933 	for (int i = 0; i < dnp->dn_nblkptr; i++)
    934 		bp->blk_fill += dnp->dn_blkptr[i].blk_fill;
    935 }
    936 
    937 /* ARGSUSED */
    938 static void
    939 dmu_objset_write_done(zio_t *zio, arc_buf_t *abuf, void *arg)
    940 {
    941 	blkptr_t *bp = zio->io_bp;
    942 	blkptr_t *bp_orig = &zio->io_bp_orig;
    943 	objset_t *os = arg;
    944 
    945 	if (zio->io_flags & ZIO_FLAG_IO_REWRITE) {
    946 		ASSERT(BP_EQUAL(bp, bp_orig));
    947 	} else {
    948 		dsl_dataset_t *ds = os->os_dsl_dataset;
    949 		dmu_tx_t *tx = os->os_synctx;
    950 
    951 		(void) dsl_dataset_block_kill(ds, bp_orig, tx, B_TRUE);
    952 		dsl_dataset_block_born(ds, bp, tx);
    953 	}
    954 }
    955 
    956 /* called from dsl */
    957 void
    958 dmu_objset_sync(objset_t *os, zio_t *pio, dmu_tx_t *tx)
    959 {
    960 	int txgoff;
    961 	zbookmark_t zb;
    962 	zio_prop_t zp;
    963 	zio_t *zio;
    964 	list_t *list;
    965 	list_t *newlist = NULL;
    966 	dbuf_dirty_record_t *dr;
    967 
    968 	dprintf_ds(os->os_dsl_dataset, "txg=%llu\n", tx->tx_txg);
    969 
    970 	ASSERT(dmu_tx_is_syncing(tx));
    971 	/* XXX the write_done callback should really give us the tx... */
    972 	os->os_synctx = tx;
    973 
    974 	if (os->os_dsl_dataset == NULL) {
    975 		/*
    976 		 * This is the MOS.  If we have upgraded,
    977 		 * spa_max_replication() could change, so reset
    978 		 * os_copies here.
    979 		 */
    980 		os->os_copies = spa_max_replication(os->os_spa);
    981 	}
    982 
    983 	/*
    984 	 * Create the root block IO
    985 	 */
    986 	arc_release(os->os_phys_buf, &os->os_phys_buf);
    987 
    988 	SET_BOOKMARK(&zb, os->os_dsl_dataset ?
    989 	    os->os_dsl_dataset->ds_object : DMU_META_OBJSET,
    990 	    ZB_ROOT_OBJECT, ZB_ROOT_LEVEL, ZB_ROOT_BLKID);
    991 
    992 	dmu_write_policy(os, NULL, 0, 0, &zp);
    993 
    994 	zio = arc_write(pio, os->os_spa, tx->tx_txg,
    995 	    os->os_rootbp, os->os_phys_buf, DMU_OS_IS_L2CACHEABLE(os), &zp,
    996 	    dmu_objset_write_ready, dmu_objset_write_done, os,
    997 	    ZIO_PRIORITY_ASYNC_WRITE, ZIO_FLAG_MUSTSUCCEED, &zb);
    998 
    999 	/*
   1000 	 * Sync special dnodes - the parent IO for the sync is the root block
   1001 	 */
   1002 	os->os_meta_dnode->dn_zio = zio;
   1003 	dnode_sync(os->os_meta_dnode, tx);
   1004 
   1005 	os->os_phys->os_flags = os->os_flags;
   1006 
   1007 	if (os->os_userused_dnode &&
   1008 	    os->os_userused_dnode->dn_type != DMU_OT_NONE) {
   1009 		os->os_userused_dnode->dn_zio = zio;
   1010 		dnode_sync(os->os_userused_dnode, tx);
   1011 		os->os_groupused_dnode->dn_zio = zio;
   1012 		dnode_sync(os->os_groupused_dnode, tx);
   1013 	}
   1014 
   1015 	txgoff = tx->tx_txg & TXG_MASK;
   1016 
   1017 	if (dmu_objset_userused_enabled(os)) {
   1018 		newlist = &os->os_synced_dnodes;
   1019 		/*
   1020 		 * We must create the list here because it uses the
   1021 		 * dn_dirty_link[] of this txg.
   1022 		 */
   1023 		list_create(newlist, sizeof (dnode_t),
   1024 		    offsetof(dnode_t, dn_dirty_link[txgoff]));
   1025 	}
   1026 
   1027 	dmu_objset_sync_dnodes(&os->os_free_dnodes[txgoff], newlist, tx);
   1028 	dmu_objset_sync_dnodes(&os->os_dirty_dnodes[txgoff], newlist, tx);
   1029 
   1030 	list = &os->os_meta_dnode->dn_dirty_records[txgoff];
   1031 	while (dr = list_head(list)) {
   1032 		ASSERT(dr->dr_dbuf->db_level == 0);
   1033 		list_remove(list, dr);
   1034 		if (dr->dr_zio)
   1035 			zio_nowait(dr->dr_zio);
   1036 	}
   1037 	/*
   1038 	 * Free intent log blocks up to this tx.
   1039 	 */
   1040 	zil_sync(os->os_zil, tx);
   1041 	os->os_phys->os_zil_header = os->os_zil_header;
   1042 	zio_nowait(zio);
   1043 }
   1044 
   1045 boolean_t
   1046 dmu_objset_is_dirty(objset_t *os, uint64_t txg)
   1047 {
   1048 	return (!list_is_empty(&os->os_dirty_dnodes[txg & TXG_MASK]) ||
   1049 	    !list_is_empty(&os->os_free_dnodes[txg & TXG_MASK]));
   1050 }
   1051 
   1052 static objset_used_cb_t *used_cbs[DMU_OST_NUMTYPES];
   1053 
   1054 void
   1055 dmu_objset_register_type(dmu_objset_type_t ost, objset_used_cb_t *cb)
   1056 {
   1057 	used_cbs[ost] = cb;
   1058 }
   1059 
   1060 boolean_t
   1061 dmu_objset_userused_enabled(objset_t *os)
   1062 {
   1063 	return (spa_version(os->os_spa) >= SPA_VERSION_USERSPACE &&
   1064 	    used_cbs[os->os_phys->os_type] &&
   1065 	    os->os_userused_dnode);
   1066 }
   1067 
   1068 static void
   1069 do_userquota_callback(objset_t *os, dnode_phys_t *dnp,
   1070     boolean_t subtract, dmu_tx_t *tx)
   1071 {
   1072 	static const char zerobuf[DN_MAX_BONUSLEN] = {0};
   1073 	uint64_t user, group;
   1074 
   1075 	ASSERT(dnp->dn_type != 0 ||
   1076 	    (bcmp(DN_BONUS(dnp), zerobuf, DN_MAX_BONUSLEN) == 0 &&
   1077 	    DN_USED_BYTES(dnp) == 0));
   1078 
   1079 	if ((dnp->dn_flags & DNODE_FLAG_USERUSED_ACCOUNTED) &&
   1080 	    0 == used_cbs[os->os_phys->os_type](dnp->dn_bonustype,
   1081 	    DN_BONUS(dnp), &user, &group)) {
   1082 		int64_t delta = DNODE_SIZE + DN_USED_BYTES(dnp);
   1083 		if (subtract)
   1084 			delta = -delta;
   1085 		VERIFY3U(0, ==, zap_increment_int(os, DMU_USERUSED_OBJECT,
   1086 		    user, delta, tx));
   1087 		VERIFY3U(0, ==, zap_increment_int(os, DMU_GROUPUSED_OBJECT,
   1088 		    group, delta, tx));
   1089 	}
   1090 }
   1091 
   1092 void
   1093 dmu_objset_do_userquota_callbacks(objset_t *os, dmu_tx_t *tx)
   1094 {
   1095 	dnode_t *dn;
   1096 	list_t *list = &os->os_synced_dnodes;
   1097 
   1098 	ASSERT(list_head(list) == NULL || dmu_objset_userused_enabled(os));
   1099 
   1100 	while (dn = list_head(list)) {
   1101 		ASSERT(!DMU_OBJECT_IS_SPECIAL(dn->dn_object));
   1102 		ASSERT(dn->dn_oldphys);
   1103 		ASSERT(dn->dn_phys->dn_type == DMU_OT_NONE ||
   1104 		    dn->dn_phys->dn_flags &
   1105 		    DNODE_FLAG_USERUSED_ACCOUNTED);
   1106 
   1107 		/* Allocate the user/groupused objects if necessary. */
   1108 		if (os->os_userused_dnode->dn_type == DMU_OT_NONE) {
   1109 			VERIFY(0 == zap_create_claim(os,
   1110 			    DMU_USERUSED_OBJECT,
   1111 			    DMU_OT_USERGROUP_USED, DMU_OT_NONE, 0, tx));
   1112 			VERIFY(0 == zap_create_claim(os,
   1113 			    DMU_GROUPUSED_OBJECT,
   1114 			    DMU_OT_USERGROUP_USED, DMU_OT_NONE, 0, tx));
   1115 		}
   1116 
   1117 		/*
   1118 		 * We intentionally modify the zap object even if the
   1119 		 * net delta (due to phys-oldphys) is zero.  Otherwise
   1120 		 * the block of the zap obj could be shared between
   1121 		 * datasets but need to be different between them after
   1122 		 * a bprewrite.
   1123 		 */
   1124 		do_userquota_callback(os, dn->dn_oldphys, B_TRUE, tx);
   1125 		do_userquota_callback(os, dn->dn_phys, B_FALSE, tx);
   1126 
   1127 		/*
   1128 		 * The mutex is needed here for interlock with dnode_allocate.
   1129 		 */
   1130 		mutex_enter(&dn->dn_mtx);
   1131 		zio_buf_free(dn->dn_oldphys, sizeof (dnode_phys_t));
   1132 		dn->dn_oldphys = NULL;
   1133 		mutex_exit(&dn->dn_mtx);
   1134 
   1135 		list_remove(list, dn);
   1136 		dnode_rele(dn, list);
   1137 	}
   1138 }
   1139 
   1140 boolean_t
   1141 dmu_objset_userspace_present(objset_t *os)
   1142 {
   1143 	return (os->os_phys->os_flags &
   1144 	    OBJSET_FLAG_USERACCOUNTING_COMPLETE);
   1145 }
   1146 
   1147 int
   1148 dmu_objset_userspace_upgrade(objset_t *os)
   1149 {
   1150 	uint64_t obj;
   1151 	int err = 0;
   1152 
   1153 	if (dmu_objset_userspace_present(os))
   1154 		return (0);
   1155 	if (!dmu_objset_userused_enabled(os))
   1156 		return (ENOTSUP);
   1157 	if (dmu_objset_is_snapshot(os))
   1158 		return (EINVAL);
   1159 
   1160 	/*
   1161 	 * We simply need to mark every object dirty, so that it will be
   1162 	 * synced out and now accounted.  If this is called
   1163 	 * concurrently, or if we already did some work before crashing,
   1164 	 * that's fine, since we track each object's accounted state
   1165 	 * independently.
   1166 	 */
   1167 
   1168 	for (obj = 0; err == 0; err = dmu_object_next(os, &obj, FALSE, 0)) {
   1169 		dmu_tx_t *tx;
   1170 		dmu_buf_t *db;
   1171 		int objerr;
   1172 
   1173 		if (issig(JUSTLOOKING) && issig(FORREAL))
   1174 			return (EINTR);
   1175 
   1176 		objerr = dmu_bonus_hold(os, obj, FTAG, &db);
   1177 		if (objerr)
   1178 			continue;
   1179 		tx = dmu_tx_create(os);
   1180 		dmu_tx_hold_bonus(tx, obj);
   1181 		objerr = dmu_tx_assign(tx, TXG_WAIT);
   1182 		if (objerr) {
   1183 			dmu_tx_abort(tx);
   1184 			continue;
   1185 		}
   1186 		dmu_buf_will_dirty(db, tx);
   1187 		dmu_buf_rele(db, FTAG);
   1188 		dmu_tx_commit(tx);
   1189 	}
   1190 
   1191 	os->os_flags |= OBJSET_FLAG_USERACCOUNTING_COMPLETE;
   1192 	txg_wait_synced(dmu_objset_pool(os), 0);
   1193 	return (0);
   1194 }
   1195 
   1196 void
   1197 dmu_objset_space(objset_t *os, uint64_t *refdbytesp, uint64_t *availbytesp,
   1198     uint64_t *usedobjsp, uint64_t *availobjsp)
   1199 {
   1200 	dsl_dataset_space(os->os_dsl_dataset, refdbytesp, availbytesp,
   1201 	    usedobjsp, availobjsp);
   1202 }
   1203 
   1204 uint64_t
   1205 dmu_objset_fsid_guid(objset_t *os)
   1206 {
   1207 	return (dsl_dataset_fsid_guid(os->os_dsl_dataset));
   1208 }
   1209 
   1210 void
   1211 dmu_objset_fast_stat(objset_t *os, dmu_objset_stats_t *stat)
   1212 {
   1213 	stat->dds_type = os->os_phys->os_type;
   1214 	if (os->os_dsl_dataset)
   1215 		dsl_dataset_fast_stat(os->os_dsl_dataset, stat);
   1216 }
   1217 
   1218 void
   1219 dmu_objset_stats(objset_t *os, nvlist_t *nv)
   1220 {
   1221 	ASSERT(os->os_dsl_dataset ||
   1222 	    os->os_phys->os_type == DMU_OST_META);
   1223 
   1224 	if (os->os_dsl_dataset != NULL)
   1225 		dsl_dataset_stats(os->os_dsl_dataset, nv);
   1226 
   1227 	dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_TYPE,
   1228 	    os->os_phys->os_type);
   1229 	dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_USERACCOUNTING,
   1230 	    dmu_objset_userspace_present(os));
   1231 }
   1232 
   1233 int
   1234 dmu_objset_is_snapshot(objset_t *os)
   1235 {
   1236 	if (os->os_dsl_dataset != NULL)
   1237 		return (dsl_dataset_is_snapshot(os->os_dsl_dataset));
   1238 	else
   1239 		return (B_FALSE);
   1240 }
   1241 
   1242 int
   1243 dmu_snapshot_realname(objset_t *os, char *name, char *real, int maxlen,
   1244     boolean_t *conflict)
   1245 {
   1246 	dsl_dataset_t *ds = os->os_dsl_dataset;
   1247 	uint64_t ignored;
   1248 
   1249 	if (ds->ds_phys->ds_snapnames_zapobj == 0)
   1250 		return (ENOENT);
   1251 
   1252 	return (zap_lookup_norm(ds->ds_dir->dd_pool->dp_meta_objset,
   1253 	    ds->ds_phys->ds_snapnames_zapobj, name, 8, 1, &ignored, MT_FIRST,
   1254 	    real, maxlen, conflict));
   1255 }
   1256 
   1257 int
   1258 dmu_snapshot_list_next(objset_t *os, int namelen, char *name,
   1259     uint64_t *idp, uint64_t *offp, boolean_t *case_conflict)
   1260 {
   1261 	dsl_dataset_t *ds = os->os_dsl_dataset;
   1262 	zap_cursor_t cursor;
   1263 	zap_attribute_t attr;
   1264 
   1265 	if (ds->ds_phys->ds_snapnames_zapobj == 0)
   1266 		return (ENOENT);
   1267 
   1268 	zap_cursor_init_serialized(&cursor,
   1269 	    ds->ds_dir->dd_pool->dp_meta_objset,
   1270 	    ds->ds_phys->ds_snapnames_zapobj, *offp);
   1271 
   1272 	if (zap_cursor_retrieve(&cursor, &attr) != 0) {
   1273 		zap_cursor_fini(&cursor);
   1274 		return (ENOENT);
   1275 	}
   1276 
   1277 	if (strlen(attr.za_name) + 1 > namelen) {
   1278 		zap_cursor_fini(&cursor);
   1279 		return (ENAMETOOLONG);
   1280 	}
   1281 
   1282 	(void) strcpy(name, attr.za_name);
   1283 	if (idp)
   1284 		*idp = attr.za_first_integer;
   1285 	if (case_conflict)
   1286 		*case_conflict = attr.za_normalization_conflict;
   1287 	zap_cursor_advance(&cursor);
   1288 	*offp = zap_cursor_serialize(&cursor);
   1289 	zap_cursor_fini(&cursor);
   1290 
   1291 	return (0);
   1292 }
   1293 
   1294 int
   1295 dmu_dir_list_next(objset_t *os, int namelen, char *name,
   1296     uint64_t *idp, uint64_t *offp)
   1297 {
   1298 	dsl_dir_t *dd = os->os_dsl_dataset->ds_dir;
   1299 	zap_cursor_t cursor;
   1300 	zap_attribute_t attr;
   1301 
   1302 	/* there is no next dir on a snapshot! */
   1303 	if (os->os_dsl_dataset->ds_object !=
   1304 	    dd->dd_phys->dd_head_dataset_obj)
   1305 		return (ENOENT);
   1306 
   1307 	zap_cursor_init_serialized(&cursor,
   1308 	    dd->dd_pool->dp_meta_objset,
   1309 	    dd->dd_phys->dd_child_dir_zapobj, *offp);
   1310 
   1311 	if (zap_cursor_retrieve(&cursor, &attr) != 0) {
   1312 		zap_cursor_fini(&cursor);
   1313 		return (ENOENT);
   1314 	}
   1315 
   1316 	if (strlen(attr.za_name) + 1 > namelen) {
   1317 		zap_cursor_fini(&cursor);
   1318 		return (ENAMETOOLONG);
   1319 	}
   1320 
   1321 	(void) strcpy(name, attr.za_name);
   1322 	if (idp)
   1323 		*idp = attr.za_first_integer;
   1324 	zap_cursor_advance(&cursor);
   1325 	*offp = zap_cursor_serialize(&cursor);
   1326 	zap_cursor_fini(&cursor);
   1327 
   1328 	return (0);
   1329 }
   1330 
   1331 struct findarg {
   1332 	int (*func)(const char *, void *);
   1333 	void *arg;
   1334 };
   1335 
   1336 /* ARGSUSED */
   1337 static int
   1338 findfunc(spa_t *spa, uint64_t dsobj, const char *dsname, void *arg)
   1339 {
   1340 	struct findarg *fa = arg;
   1341 	return (fa->func(dsname, fa->arg));
   1342 }
   1343 
   1344 /*
   1345  * Find all objsets under name, and for each, call 'func(child_name, arg)'.
   1346  * Perhaps change all callers to use dmu_objset_find_spa()?
   1347  */
   1348 int
   1349 dmu_objset_find(char *name, int func(const char *, void *), void *arg,
   1350     int flags)
   1351 {
   1352 	struct findarg fa;
   1353 	fa.func = func;
   1354 	fa.arg = arg;
   1355 	return (dmu_objset_find_spa(NULL, name, findfunc, &fa, flags));
   1356 }
   1357 
   1358 /*
   1359  * Find all objsets under name, call func on each
   1360  */
   1361 int
   1362 dmu_objset_find_spa(spa_t *spa, const char *name,
   1363     int func(spa_t *, uint64_t, const char *, void *), void *arg, int flags)
   1364 {
   1365 	dsl_dir_t *dd;
   1366 	dsl_pool_t *dp;
   1367 	dsl_dataset_t *ds;
   1368 	zap_cursor_t zc;
   1369 	zap_attribute_t *attr;
   1370 	char *child;
   1371 	uint64_t thisobj;
   1372 	int err;
   1373 
   1374 	if (name == NULL)
   1375 		name = spa_name(spa);
   1376 	err = dsl_dir_open_spa(spa, name, FTAG, &dd, NULL);
   1377 	if (err)
   1378 		return (err);
   1379 
   1380 	/* Don't visit hidden ($MOS & $ORIGIN) objsets. */
   1381 	if (dd->dd_myname[0] == '$') {
   1382 		dsl_dir_close(dd, FTAG);
   1383 		return (0);
   1384 	}
   1385 
   1386 	thisobj = dd->dd_phys->dd_head_dataset_obj;
   1387 	attr = kmem_alloc(sizeof (zap_attribute_t), KM_SLEEP);
   1388 	dp = dd->dd_pool;
   1389 
   1390 	/*
   1391 	 * Iterate over all children.
   1392 	 */
   1393 	if (flags & DS_FIND_CHILDREN) {
   1394 		for (zap_cursor_init(&zc, dp->dp_meta_objset,
   1395 		    dd->dd_phys->dd_child_dir_zapobj);
   1396 		    zap_cursor_retrieve(&zc, attr) == 0;
   1397 		    (void) zap_cursor_advance(&zc)) {
   1398 			ASSERT(attr->za_integer_length == sizeof (uint64_t));
   1399 			ASSERT(attr->za_num_integers == 1);
   1400 
   1401 			child = kmem_asprintf("%s/%s", name, attr->za_name);
   1402 			err = dmu_objset_find_spa(spa, child, func, arg, flags);
   1403 			strfree(child);
   1404 			if (err)
   1405 				break;
   1406 		}
   1407 		zap_cursor_fini(&zc);
   1408 
   1409 		if (err) {
   1410 			dsl_dir_close(dd, FTAG);
   1411 			kmem_free(attr, sizeof (zap_attribute_t));
   1412 			return (err);
   1413 		}
   1414 	}
   1415 
   1416 	/*
   1417 	 * Iterate over all snapshots.
   1418 	 */
   1419 	if (flags & DS_FIND_SNAPSHOTS) {
   1420 		if (!dsl_pool_sync_context(dp))
   1421 			rw_enter(&dp->dp_config_rwlock, RW_READER);
   1422 		err = dsl_dataset_hold_obj(dp, thisobj, FTAG, &ds);
   1423 		if (!dsl_pool_sync_context(dp))
   1424 			rw_exit(&dp->dp_config_rwlock);
   1425 
   1426 		if (err == 0) {
   1427 			uint64_t snapobj = ds->ds_phys->ds_snapnames_zapobj;
   1428 			dsl_dataset_rele(ds, FTAG);
   1429 
   1430 			for (zap_cursor_init(&zc, dp->dp_meta_objset, snapobj);
   1431 			    zap_cursor_retrieve(&zc, attr) == 0;
   1432 			    (void) zap_cursor_advance(&zc)) {
   1433 				ASSERT(attr->za_integer_length ==
   1434 				    sizeof (uint64_t));
   1435 				ASSERT(attr->za_num_integers == 1);
   1436 
   1437 				child = kmem_asprintf("%s@%s",
   1438 				    name, attr->za_name);
   1439 				err = func(spa, attr->za_first_integer,
   1440 				    child, arg);
   1441 				strfree(child);
   1442 				if (err)
   1443 					break;
   1444 			}
   1445 			zap_cursor_fini(&zc);
   1446 		}
   1447 	}
   1448 
   1449 	dsl_dir_close(dd, FTAG);
   1450 	kmem_free(attr, sizeof (zap_attribute_t));
   1451 
   1452 	if (err)
   1453 		return (err);
   1454 
   1455 	/*
   1456 	 * Apply to self if appropriate.
   1457 	 */
   1458 	err = func(spa, thisobj, name, arg);
   1459 	return (err);
   1460 }
   1461 
   1462 /* ARGSUSED */
   1463 int
   1464 dmu_objset_prefetch(const char *name, void *arg)
   1465 {
   1466 	dsl_dataset_t *ds;
   1467 
   1468 	if (dsl_dataset_hold(name, FTAG, &ds))
   1469 		return (0);
   1470 
   1471 	if (!BP_IS_HOLE(&ds->ds_phys->ds_bp)) {
   1472 		mutex_enter(&ds->ds_opening_lock);
   1473 		if (ds->ds_objset == NULL) {
   1474 			uint32_t aflags = ARC_NOWAIT | ARC_PREFETCH;
   1475 			zbookmark_t zb;
   1476 
   1477 			SET_BOOKMARK(&zb, ds->ds_object, ZB_ROOT_OBJECT,
   1478 			    ZB_ROOT_LEVEL, ZB_ROOT_BLKID);
   1479 
   1480 			(void) arc_read_nolock(NULL, dsl_dataset_get_spa(ds),
   1481 			    &ds->ds_phys->ds_bp, NULL, NULL,
   1482 			    ZIO_PRIORITY_ASYNC_READ,
   1483 			    ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE,
   1484 			    &aflags, &zb);
   1485 		}
   1486 		mutex_exit(&ds->ds_opening_lock);
   1487 	}
   1488 
   1489 	dsl_dataset_rele(ds, FTAG);
   1490 	return (0);
   1491 }
   1492 
   1493 void
   1494 dmu_objset_set_user(objset_t *os, void *user_ptr)
   1495 {
   1496 	ASSERT(MUTEX_HELD(&os->os_user_ptr_lock));
   1497 	os->os_user_ptr = user_ptr;
   1498 }
   1499 
   1500 void *
   1501 dmu_objset_get_user(objset_t *os)
   1502 {
   1503 	ASSERT(MUTEX_HELD(&os->os_user_ptr_lock));
   1504 	return (os->os_user_ptr);
   1505 }
   1506