xref: /titanic_51/usr/src/uts/common/fs/zfs/dsl_prop.c (revision 4f60987df4dcaa54a88b596f861fbf4f3382c65e)
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 2009 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #include <sys/zfs_context.h>
27 #include <sys/dmu.h>
28 #include <sys/dmu_objset.h>
29 #include <sys/dmu_tx.h>
30 #include <sys/dsl_dataset.h>
31 #include <sys/dsl_dir.h>
32 #include <sys/dsl_prop.h>
33 #include <sys/dsl_synctask.h>
34 #include <sys/spa.h>
35 #include <sys/zap.h>
36 #include <sys/fs/zfs.h>
37 
38 #include "zfs_prop.h"
39 
40 #define	ZPROP_INHERIT_SUFFIX "$inherit"
41 #define	ZPROP_RECVD_SUFFIX "$recvd"
42 
43 static int
44 dodefault(const char *propname, int intsz, int numints, void *buf)
45 {
46 	zfs_prop_t prop;
47 
48 	/*
49 	 * The setonce properties are read-only, BUT they still
50 	 * have a default value that can be used as the initial
51 	 * value.
52 	 */
53 	if ((prop = zfs_name_to_prop(propname)) == ZPROP_INVAL ||
54 	    (zfs_prop_readonly(prop) && !zfs_prop_setonce(prop)))
55 		return (ENOENT);
56 
57 	if (zfs_prop_get_type(prop) == PROP_TYPE_STRING) {
58 		if (intsz != 1)
59 			return (EOVERFLOW);
60 		(void) strncpy(buf, zfs_prop_default_string(prop),
61 		    numints);
62 	} else {
63 		if (intsz != 8 || numints < 1)
64 			return (EOVERFLOW);
65 
66 		*(uint64_t *)buf = zfs_prop_default_numeric(prop);
67 	}
68 
69 	return (0);
70 }
71 
72 int
73 dsl_prop_get_dd(dsl_dir_t *dd, const char *propname,
74     int intsz, int numints, void *buf, char *setpoint, boolean_t snapshot)
75 {
76 	int err = ENOENT;
77 	dsl_dir_t *target = dd;
78 	objset_t *mos = dd->dd_pool->dp_meta_objset;
79 	zfs_prop_t prop;
80 	boolean_t inheritable;
81 	boolean_t inheriting = B_FALSE;
82 	char *inheritstr;
83 	char *recvdstr;
84 
85 	ASSERT(RW_LOCK_HELD(&dd->dd_pool->dp_config_rwlock));
86 
87 	if (setpoint)
88 		setpoint[0] = '\0';
89 
90 	prop = zfs_name_to_prop(propname);
91 	inheritable = (prop == ZPROP_INVAL || zfs_prop_inheritable(prop));
92 	inheritstr = kmem_asprintf("%s%s", propname, ZPROP_INHERIT_SUFFIX);
93 	recvdstr = kmem_asprintf("%s%s", propname, ZPROP_RECVD_SUFFIX);
94 
95 	/*
96 	 * Note: dd may become NULL, therefore we shouldn't dereference it
97 	 * after this loop.
98 	 */
99 	for (; dd != NULL; dd = dd->dd_parent) {
100 		ASSERT(RW_LOCK_HELD(&dd->dd_pool->dp_config_rwlock));
101 
102 		if (dd != target || snapshot) {
103 			if (!inheritable)
104 				break;
105 			inheriting = B_TRUE;
106 		}
107 
108 		/* Check for a local value. */
109 		err = zap_lookup(mos, dd->dd_phys->dd_props_zapobj, propname,
110 		    intsz, numints, buf);
111 		if (err != ENOENT) {
112 			if (setpoint != NULL && err == 0)
113 				dsl_dir_name(dd, setpoint);
114 			break;
115 		}
116 
117 		/*
118 		 * Skip the check for a received value if there is an explicit
119 		 * inheritance entry.
120 		 */
121 		err = zap_contains(mos, dd->dd_phys->dd_props_zapobj,
122 		    inheritstr);
123 		if (err != 0 && err != ENOENT)
124 			break;
125 
126 		if (err == ENOENT) {
127 			/* Check for a received value. */
128 			err = zap_lookup(mos, dd->dd_phys->dd_props_zapobj,
129 			    recvdstr, intsz, numints, buf);
130 			if (err != ENOENT) {
131 				if (setpoint != NULL && err == 0) {
132 					if (inheriting) {
133 						dsl_dir_name(dd, setpoint);
134 					} else {
135 						(void) strcpy(setpoint,
136 						    ZPROP_SOURCE_VAL_RECVD);
137 					}
138 				}
139 				break;
140 			}
141 		}
142 
143 		/*
144 		 * If we found an explicit inheritance entry, err is zero even
145 		 * though we haven't yet found the value, so reinitializing err
146 		 * at the end of the loop (instead of at the beginning) ensures
147 		 * that err has a valid post-loop value.
148 		 */
149 		err = ENOENT;
150 	}
151 
152 	if (err == ENOENT)
153 		err = dodefault(propname, intsz, numints, buf);
154 
155 	strfree(inheritstr);
156 	strfree(recvdstr);
157 
158 	return (err);
159 }
160 
161 int
162 dsl_prop_get_ds(dsl_dataset_t *ds, const char *propname,
163     int intsz, int numints, void *buf, char *setpoint)
164 {
165 	zfs_prop_t prop = zfs_name_to_prop(propname);
166 	boolean_t inheritable;
167 	boolean_t snapshot;
168 	uint64_t zapobj;
169 
170 	ASSERT(RW_LOCK_HELD(&ds->ds_dir->dd_pool->dp_config_rwlock));
171 	inheritable = (prop == ZPROP_INVAL || zfs_prop_inheritable(prop));
172 	snapshot = (ds->ds_phys != NULL && dsl_dataset_is_snapshot(ds));
173 	zapobj = (ds->ds_phys == NULL ? 0 : ds->ds_phys->ds_props_obj);
174 
175 	if (zapobj != 0) {
176 		objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
177 		int err;
178 
179 		ASSERT(snapshot);
180 
181 		/* Check for a local value. */
182 		err = zap_lookup(mos, zapobj, propname, intsz, numints, buf);
183 		if (err != ENOENT) {
184 			if (setpoint != NULL && err == 0)
185 				dsl_dataset_name(ds, setpoint);
186 			return (err);
187 		}
188 
189 		/*
190 		 * Skip the check for a received value if there is an explicit
191 		 * inheritance entry.
192 		 */
193 		if (inheritable) {
194 			char *inheritstr = kmem_asprintf("%s%s", propname,
195 			    ZPROP_INHERIT_SUFFIX);
196 			err = zap_contains(mos, zapobj, inheritstr);
197 			strfree(inheritstr);
198 			if (err != 0 && err != ENOENT)
199 				return (err);
200 		}
201 
202 		if (err == ENOENT) {
203 			/* Check for a received value. */
204 			char *recvdstr = kmem_asprintf("%s%s", propname,
205 			    ZPROP_RECVD_SUFFIX);
206 			err = zap_lookup(mos, zapobj, recvdstr,
207 			    intsz, numints, buf);
208 			strfree(recvdstr);
209 			if (err != ENOENT) {
210 				if (setpoint != NULL && err == 0)
211 					(void) strcpy(setpoint,
212 					    ZPROP_SOURCE_VAL_RECVD);
213 				return (err);
214 			}
215 		}
216 	}
217 
218 	return (dsl_prop_get_dd(ds->ds_dir, propname,
219 	    intsz, numints, buf, setpoint, snapshot));
220 }
221 
222 /*
223  * Register interest in the named property.  We'll call the callback
224  * once to notify it of the current property value, and again each time
225  * the property changes, until this callback is unregistered.
226  *
227  * Return 0 on success, errno if the prop is not an integer value.
228  */
229 int
230 dsl_prop_register(dsl_dataset_t *ds, const char *propname,
231     dsl_prop_changed_cb_t *callback, void *cbarg)
232 {
233 	dsl_dir_t *dd = ds->ds_dir;
234 	dsl_pool_t *dp = dd->dd_pool;
235 	uint64_t value;
236 	dsl_prop_cb_record_t *cbr;
237 	int err;
238 	int need_rwlock;
239 
240 	need_rwlock = !RW_WRITE_HELD(&dp->dp_config_rwlock);
241 	if (need_rwlock)
242 		rw_enter(&dp->dp_config_rwlock, RW_READER);
243 
244 	err = dsl_prop_get_ds(ds, propname, 8, 1, &value, NULL);
245 	if (err != 0) {
246 		if (need_rwlock)
247 			rw_exit(&dp->dp_config_rwlock);
248 		return (err);
249 	}
250 
251 	cbr = kmem_alloc(sizeof (dsl_prop_cb_record_t), KM_SLEEP);
252 	cbr->cbr_ds = ds;
253 	cbr->cbr_propname = kmem_alloc(strlen(propname)+1, KM_SLEEP);
254 	(void) strcpy((char *)cbr->cbr_propname, propname);
255 	cbr->cbr_func = callback;
256 	cbr->cbr_arg = cbarg;
257 	mutex_enter(&dd->dd_lock);
258 	list_insert_head(&dd->dd_prop_cbs, cbr);
259 	mutex_exit(&dd->dd_lock);
260 
261 	cbr->cbr_func(cbr->cbr_arg, value);
262 
263 	VERIFY(0 == dsl_dir_open_obj(dp, dd->dd_object,
264 	    NULL, cbr, &dd));
265 	if (need_rwlock)
266 		rw_exit(&dp->dp_config_rwlock);
267 	/* Leave dir open until this callback is unregistered */
268 	return (0);
269 }
270 
271 int
272 dsl_prop_get(const char *dsname, const char *propname,
273     int intsz, int numints, void *buf, char *setpoint)
274 {
275 	dsl_dataset_t *ds;
276 	int err;
277 
278 	err = dsl_dataset_hold(dsname, FTAG, &ds);
279 	if (err)
280 		return (err);
281 
282 	rw_enter(&ds->ds_dir->dd_pool->dp_config_rwlock, RW_READER);
283 	err = dsl_prop_get_ds(ds, propname, intsz, numints, buf, setpoint);
284 	rw_exit(&ds->ds_dir->dd_pool->dp_config_rwlock);
285 
286 	dsl_dataset_rele(ds, FTAG);
287 	return (err);
288 }
289 
290 /*
291  * Get the current property value.  It may have changed by the time this
292  * function returns, so it is NOT safe to follow up with
293  * dsl_prop_register() and assume that the value has not changed in
294  * between.
295  *
296  * Return 0 on success, ENOENT if ddname is invalid.
297  */
298 int
299 dsl_prop_get_integer(const char *ddname, const char *propname,
300     uint64_t *valuep, char *setpoint)
301 {
302 	return (dsl_prop_get(ddname, propname, 8, 1, valuep, setpoint));
303 }
304 
305 void
306 dsl_prop_setarg_init_uint64(dsl_prop_setarg_t *psa, const char *propname,
307     zprop_source_t source, uint64_t *value)
308 {
309 	psa->psa_name = propname;
310 	psa->psa_source = source;
311 	psa->psa_intsz = 8;
312 	psa->psa_numints = 1;
313 	psa->psa_value = value;
314 
315 	psa->psa_effective_value = -1ULL;
316 }
317 
318 /*
319  * Predict the effective value of the given special property if it were set with
320  * the given value and source. This is not a general purpose function. It exists
321  * only to handle the special requirements of the quota and reservation
322  * properties. The fact that these properties are non-inheritable greatly
323  * simplifies the prediction logic.
324  *
325  * Returns 0 on success, a positive error code on failure, or -1 if called with
326  * a property not handled by this function.
327  */
328 int
329 dsl_prop_predict_sync(dsl_dir_t *dd, dsl_prop_setarg_t *psa)
330 {
331 	const char *propname = psa->psa_name;
332 	zfs_prop_t prop = zfs_name_to_prop(propname);
333 	zprop_source_t source = psa->psa_source;
334 	objset_t *mos;
335 	uint64_t zapobj;
336 	uint64_t version;
337 	char *recvdstr;
338 	int err = 0;
339 
340 	switch (prop) {
341 	case ZFS_PROP_QUOTA:
342 	case ZFS_PROP_RESERVATION:
343 	case ZFS_PROP_REFQUOTA:
344 	case ZFS_PROP_REFRESERVATION:
345 		break;
346 	default:
347 		return (-1);
348 	}
349 
350 	mos = dd->dd_pool->dp_meta_objset;
351 	zapobj = dd->dd_phys->dd_props_zapobj;
352 	recvdstr = kmem_asprintf("%s%s", propname, ZPROP_RECVD_SUFFIX);
353 
354 	version = spa_version(dd->dd_pool->dp_spa);
355 	if (version < SPA_VERSION_RECVD_PROPS) {
356 		if (source & ZPROP_SRC_NONE)
357 			source = ZPROP_SRC_NONE;
358 		else if (source & ZPROP_SRC_RECEIVED)
359 			source = ZPROP_SRC_LOCAL;
360 	}
361 
362 	switch (source) {
363 	case ZPROP_SRC_NONE:
364 		/* Revert to the received value, if any. */
365 		err = zap_lookup(mos, zapobj, recvdstr, 8, 1,
366 		    &psa->psa_effective_value);
367 		if (err == ENOENT)
368 			psa->psa_effective_value = 0;
369 		break;
370 	case ZPROP_SRC_LOCAL:
371 		psa->psa_effective_value = *(uint64_t *)psa->psa_value;
372 		break;
373 	case ZPROP_SRC_RECEIVED:
374 		/*
375 		 * If there's no local setting, then the new received value will
376 		 * be the effective value.
377 		 */
378 		err = zap_lookup(mos, zapobj, propname, 8, 1,
379 		    &psa->psa_effective_value);
380 		if (err == ENOENT)
381 			psa->psa_effective_value = *(uint64_t *)psa->psa_value;
382 		break;
383 	case (ZPROP_SRC_NONE | ZPROP_SRC_RECEIVED):
384 		/*
385 		 * We're clearing the received value, so the local setting (if
386 		 * it exists) remains the effective value.
387 		 */
388 		err = zap_lookup(mos, zapobj, propname, 8, 1,
389 		    &psa->psa_effective_value);
390 		if (err == ENOENT)
391 			psa->psa_effective_value = 0;
392 		break;
393 	default:
394 		cmn_err(CE_PANIC, "unexpected property source: %d", source);
395 	}
396 
397 	strfree(recvdstr);
398 
399 	if (err == ENOENT)
400 		return (0);
401 
402 	return (err);
403 }
404 
405 #ifdef	ZFS_DEBUG
406 void
407 dsl_prop_check_prediction(dsl_dir_t *dd, dsl_prop_setarg_t *psa)
408 {
409 	zfs_prop_t prop = zfs_name_to_prop(psa->psa_name);
410 	uint64_t intval;
411 	char setpoint[MAXNAMELEN];
412 	uint64_t version = spa_version(dd->dd_pool->dp_spa);
413 	int err;
414 
415 	if (version < SPA_VERSION_RECVD_PROPS) {
416 		switch (prop) {
417 		case ZFS_PROP_QUOTA:
418 		case ZFS_PROP_RESERVATION:
419 			return;
420 		}
421 	}
422 
423 	err = dsl_prop_get_dd(dd, psa->psa_name, 8, 1, &intval,
424 	    setpoint, B_FALSE);
425 	if (err == 0 && intval != psa->psa_effective_value) {
426 		cmn_err(CE_PANIC, "%s property, source: %x, "
427 		    "predicted effective value: %llu, "
428 		    "actual effective value: %llu (setpoint: %s)",
429 		    psa->psa_name, psa->psa_source,
430 		    (unsigned long long)psa->psa_effective_value,
431 		    (unsigned long long)intval, setpoint);
432 	}
433 }
434 #endif
435 
436 /*
437  * Unregister this callback.  Return 0 on success, ENOENT if ddname is
438  * invalid, ENOMSG if no matching callback registered.
439  */
440 int
441 dsl_prop_unregister(dsl_dataset_t *ds, const char *propname,
442     dsl_prop_changed_cb_t *callback, void *cbarg)
443 {
444 	dsl_dir_t *dd = ds->ds_dir;
445 	dsl_prop_cb_record_t *cbr;
446 
447 	mutex_enter(&dd->dd_lock);
448 	for (cbr = list_head(&dd->dd_prop_cbs);
449 	    cbr; cbr = list_next(&dd->dd_prop_cbs, cbr)) {
450 		if (cbr->cbr_ds == ds &&
451 		    cbr->cbr_func == callback &&
452 		    cbr->cbr_arg == cbarg &&
453 		    strcmp(cbr->cbr_propname, propname) == 0)
454 			break;
455 	}
456 
457 	if (cbr == NULL) {
458 		mutex_exit(&dd->dd_lock);
459 		return (ENOMSG);
460 	}
461 
462 	list_remove(&dd->dd_prop_cbs, cbr);
463 	mutex_exit(&dd->dd_lock);
464 	kmem_free((void*)cbr->cbr_propname, strlen(cbr->cbr_propname)+1);
465 	kmem_free(cbr, sizeof (dsl_prop_cb_record_t));
466 
467 	/* Clean up from dsl_prop_register */
468 	dsl_dir_close(dd, cbr);
469 	return (0);
470 }
471 
472 /*
473  * Return the number of callbacks that are registered for this dataset.
474  */
475 int
476 dsl_prop_numcb(dsl_dataset_t *ds)
477 {
478 	dsl_dir_t *dd = ds->ds_dir;
479 	dsl_prop_cb_record_t *cbr;
480 	int num = 0;
481 
482 	mutex_enter(&dd->dd_lock);
483 	for (cbr = list_head(&dd->dd_prop_cbs);
484 	    cbr; cbr = list_next(&dd->dd_prop_cbs, cbr)) {
485 		if (cbr->cbr_ds == ds)
486 			num++;
487 	}
488 	mutex_exit(&dd->dd_lock);
489 
490 	return (num);
491 }
492 
493 static void
494 dsl_prop_changed_notify(dsl_pool_t *dp, uint64_t ddobj,
495     const char *propname, uint64_t value, int first)
496 {
497 	dsl_dir_t *dd;
498 	dsl_prop_cb_record_t *cbr;
499 	objset_t *mos = dp->dp_meta_objset;
500 	zap_cursor_t zc;
501 	zap_attribute_t *za;
502 	int err;
503 
504 	ASSERT(RW_WRITE_HELD(&dp->dp_config_rwlock));
505 	err = dsl_dir_open_obj(dp, ddobj, NULL, FTAG, &dd);
506 	if (err)
507 		return;
508 
509 	if (!first) {
510 		/*
511 		 * If the prop is set here, then this change is not
512 		 * being inherited here or below; stop the recursion.
513 		 */
514 		err = zap_contains(mos, dd->dd_phys->dd_props_zapobj, propname);
515 		if (err == 0) {
516 			dsl_dir_close(dd, FTAG);
517 			return;
518 		}
519 		ASSERT3U(err, ==, ENOENT);
520 	}
521 
522 	mutex_enter(&dd->dd_lock);
523 	for (cbr = list_head(&dd->dd_prop_cbs); cbr;
524 	    cbr = list_next(&dd->dd_prop_cbs, cbr)) {
525 		uint64_t propobj = cbr->cbr_ds->ds_phys->ds_props_obj;
526 
527 		if (strcmp(cbr->cbr_propname, propname) != 0)
528 			continue;
529 
530 		/*
531 		 * If the property is set on this ds, then it is not
532 		 * inherited here; don't call the callback.
533 		 */
534 		if (propobj && 0 == zap_contains(mos, propobj, propname))
535 			continue;
536 
537 		cbr->cbr_func(cbr->cbr_arg, value);
538 	}
539 	mutex_exit(&dd->dd_lock);
540 
541 	za = kmem_alloc(sizeof (zap_attribute_t), KM_SLEEP);
542 	for (zap_cursor_init(&zc, mos,
543 	    dd->dd_phys->dd_child_dir_zapobj);
544 	    zap_cursor_retrieve(&zc, za) == 0;
545 	    zap_cursor_advance(&zc)) {
546 		dsl_prop_changed_notify(dp, za->za_first_integer,
547 		    propname, value, FALSE);
548 	}
549 	kmem_free(za, sizeof (zap_attribute_t));
550 	zap_cursor_fini(&zc);
551 	dsl_dir_close(dd, FTAG);
552 }
553 
554 void
555 dsl_prop_set_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx)
556 {
557 	dsl_dataset_t *ds = arg1;
558 	dsl_prop_setarg_t *psa = arg2;
559 	objset_t *mos = ds->ds_dir->dd_pool->dp_meta_objset;
560 	uint64_t zapobj, intval, dummy;
561 	int isint;
562 	char valbuf[32];
563 	char *valstr = NULL;
564 	char *inheritstr;
565 	char *recvdstr;
566 	char *tbuf = NULL;
567 	int err;
568 	uint64_t version = spa_version(ds->ds_dir->dd_pool->dp_spa);
569 	const char *propname = psa->psa_name;
570 	zprop_source_t source = psa->psa_source;
571 
572 	isint = (dodefault(propname, 8, 1, &intval) == 0);
573 
574 	if (ds->ds_phys != NULL && dsl_dataset_is_snapshot(ds)) {
575 		ASSERT(version >= SPA_VERSION_SNAP_PROPS);
576 		if (ds->ds_phys->ds_props_obj == 0) {
577 			dmu_buf_will_dirty(ds->ds_dbuf, tx);
578 			ds->ds_phys->ds_props_obj =
579 			    zap_create(mos,
580 			    DMU_OT_DSL_PROPS, DMU_OT_NONE, 0, tx);
581 		}
582 		zapobj = ds->ds_phys->ds_props_obj;
583 	} else {
584 		zapobj = ds->ds_dir->dd_phys->dd_props_zapobj;
585 	}
586 
587 	if (version < SPA_VERSION_RECVD_PROPS) {
588 		zfs_prop_t prop = zfs_name_to_prop(propname);
589 		if (prop == ZFS_PROP_QUOTA || prop == ZFS_PROP_RESERVATION)
590 			return;
591 
592 		if (source & ZPROP_SRC_NONE)
593 			source = ZPROP_SRC_NONE;
594 		else if (source & ZPROP_SRC_RECEIVED)
595 			source = ZPROP_SRC_LOCAL;
596 	}
597 
598 	inheritstr = kmem_asprintf("%s%s", propname, ZPROP_INHERIT_SUFFIX);
599 	recvdstr = kmem_asprintf("%s%s", propname, ZPROP_RECVD_SUFFIX);
600 
601 	switch (source) {
602 	case ZPROP_SRC_NONE:
603 		/*
604 		 * revert to received value, if any (inherit -S)
605 		 * - remove propname
606 		 * - remove propname$inherit
607 		 */
608 		err = zap_remove(mos, zapobj, propname, tx);
609 		ASSERT(err == 0 || err == ENOENT);
610 		err = zap_remove(mos, zapobj, inheritstr, tx);
611 		ASSERT(err == 0 || err == ENOENT);
612 		break;
613 	case ZPROP_SRC_LOCAL:
614 		/*
615 		 * remove propname$inherit
616 		 * set propname -> value
617 		 */
618 		err = zap_remove(mos, zapobj, inheritstr, tx);
619 		ASSERT(err == 0 || err == ENOENT);
620 		VERIFY(0 == zap_update(mos, zapobj, propname,
621 		    psa->psa_intsz, psa->psa_numints, psa->psa_value, tx));
622 		break;
623 	case ZPROP_SRC_INHERITED:
624 		/*
625 		 * explicitly inherit
626 		 * - remove propname
627 		 * - set propname$inherit
628 		 */
629 		err = zap_remove(mos, zapobj, propname, tx);
630 		ASSERT(err == 0 || err == ENOENT);
631 		if (version >= SPA_VERSION_RECVD_PROPS &&
632 		    zap_contains(mos, zapobj, ZPROP_HAS_RECVD) == 0) {
633 			dummy = 0;
634 			err = zap_update(mos, zapobj, inheritstr,
635 			    8, 1, &dummy, tx);
636 			ASSERT(err == 0);
637 		}
638 		break;
639 	case ZPROP_SRC_RECEIVED:
640 		/*
641 		 * set propname$recvd -> value
642 		 */
643 		err = zap_update(mos, zapobj, recvdstr,
644 		    psa->psa_intsz, psa->psa_numints, psa->psa_value, tx);
645 		ASSERT(err == 0);
646 		break;
647 	case (ZPROP_SRC_NONE | ZPROP_SRC_LOCAL | ZPROP_SRC_RECEIVED):
648 		/*
649 		 * clear local and received settings
650 		 * - remove propname
651 		 * - remove propname$inherit
652 		 * - remove propname$recvd
653 		 */
654 		err = zap_remove(mos, zapobj, propname, tx);
655 		ASSERT(err == 0 || err == ENOENT);
656 		err = zap_remove(mos, zapobj, inheritstr, tx);
657 		ASSERT(err == 0 || err == ENOENT);
658 		/* FALLTHRU */
659 	case (ZPROP_SRC_NONE | ZPROP_SRC_RECEIVED):
660 		/*
661 		 * remove propname$recvd
662 		 */
663 		err = zap_remove(mos, zapobj, recvdstr, tx);
664 		ASSERT(err == 0 || err == ENOENT);
665 		break;
666 	default:
667 		cmn_err(CE_PANIC, "unexpected property source: %d", source);
668 	}
669 
670 	strfree(inheritstr);
671 	strfree(recvdstr);
672 
673 	if (isint) {
674 		VERIFY(0 == dsl_prop_get_ds(ds, propname, 8, 1, &intval, NULL));
675 
676 		if (ds->ds_phys != NULL && dsl_dataset_is_snapshot(ds)) {
677 			dsl_prop_cb_record_t *cbr;
678 			/*
679 			 * It's a snapshot; nothing can inherit this
680 			 * property, so just look for callbacks on this
681 			 * ds here.
682 			 */
683 			mutex_enter(&ds->ds_dir->dd_lock);
684 			for (cbr = list_head(&ds->ds_dir->dd_prop_cbs); cbr;
685 			    cbr = list_next(&ds->ds_dir->dd_prop_cbs, cbr)) {
686 				if (cbr->cbr_ds == ds &&
687 				    strcmp(cbr->cbr_propname, propname) == 0)
688 					cbr->cbr_func(cbr->cbr_arg, intval);
689 			}
690 			mutex_exit(&ds->ds_dir->dd_lock);
691 		} else {
692 			dsl_prop_changed_notify(ds->ds_dir->dd_pool,
693 			    ds->ds_dir->dd_object, propname, intval, TRUE);
694 		}
695 
696 		(void) snprintf(valbuf, sizeof (valbuf),
697 		    "%lld", (longlong_t)intval);
698 		valstr = valbuf;
699 	} else {
700 		if (source == ZPROP_SRC_LOCAL) {
701 			valstr = (char *)psa->psa_value;
702 		} else {
703 			tbuf = kmem_alloc(ZAP_MAXVALUELEN, KM_SLEEP);
704 			if (dsl_prop_get_ds(ds, propname, 1,
705 			    ZAP_MAXVALUELEN, tbuf, NULL) == 0)
706 				valstr = tbuf;
707 		}
708 	}
709 
710 	spa_history_internal_log((source == ZPROP_SRC_NONE ||
711 	    source == ZPROP_SRC_INHERITED) ? LOG_DS_INHERIT :
712 	    LOG_DS_PROPSET, ds->ds_dir->dd_pool->dp_spa, tx, cr,
713 	    "%s=%s dataset = %llu", propname,
714 	    (valstr == NULL ? "" : valstr), ds->ds_object);
715 
716 	if (tbuf != NULL)
717 		kmem_free(tbuf, ZAP_MAXVALUELEN);
718 }
719 
720 void
721 dsl_props_set_sync(void *arg1, void *arg2, cred_t *cr, dmu_tx_t *tx)
722 {
723 	dsl_dataset_t *ds = arg1;
724 	dsl_props_arg_t *pa = arg2;
725 	nvlist_t *props = pa->pa_props;
726 	dsl_prop_setarg_t psa;
727 	nvpair_t *elem = NULL;
728 
729 	psa.psa_source = pa->pa_source;
730 
731 	while ((elem = nvlist_next_nvpair(props, elem)) != NULL) {
732 		nvpair_t *pair = elem;
733 
734 		psa.psa_name = nvpair_name(pair);
735 
736 		if (nvpair_type(pair) == DATA_TYPE_NVLIST) {
737 			/*
738 			 * dsl_prop_get_all_impl() returns properties in this
739 			 * format.
740 			 */
741 			nvlist_t *attrs;
742 			VERIFY(nvpair_value_nvlist(pair, &attrs) == 0);
743 			VERIFY(nvlist_lookup_nvpair(attrs, ZPROP_VALUE,
744 			    &pair) == 0);
745 		}
746 
747 		if (nvpair_type(pair) == DATA_TYPE_STRING) {
748 			VERIFY(nvpair_value_string(pair,
749 			    (char **)&psa.psa_value) == 0);
750 			psa.psa_intsz = 1;
751 			psa.psa_numints = strlen(psa.psa_value) + 1;
752 		} else {
753 			uint64_t intval;
754 			VERIFY(nvpair_value_uint64(pair, &intval) == 0);
755 			psa.psa_intsz = sizeof (intval);
756 			psa.psa_numints = 1;
757 			psa.psa_value = &intval;
758 		}
759 		dsl_prop_set_sync(ds, &psa, cr, tx);
760 	}
761 }
762 
763 void
764 dsl_dir_prop_set_uint64_sync(dsl_dir_t *dd, const char *name, uint64_t val,
765     cred_t *cr, dmu_tx_t *tx)
766 {
767 	objset_t *mos = dd->dd_pool->dp_meta_objset;
768 	uint64_t zapobj = dd->dd_phys->dd_props_zapobj;
769 
770 	ASSERT(dmu_tx_is_syncing(tx));
771 
772 	VERIFY(0 == zap_update(mos, zapobj, name, sizeof (val), 1, &val, tx));
773 
774 	dsl_prop_changed_notify(dd->dd_pool, dd->dd_object, name, val, TRUE);
775 
776 	spa_history_internal_log(LOG_DS_PROPSET, dd->dd_pool->dp_spa, tx, cr,
777 	    "%s=%llu dataset = %llu", name, (u_longlong_t)val,
778 	    dd->dd_phys->dd_head_dataset_obj);
779 }
780 
781 int
782 dsl_prop_set(const char *dsname, const char *propname, zprop_source_t source,
783     int intsz, int numints, const void *buf)
784 {
785 	dsl_dataset_t *ds;
786 	uint64_t version;
787 	int err;
788 	dsl_prop_setarg_t psa;
789 
790 	/*
791 	 * We must do these checks before we get to the syncfunc, since
792 	 * it can't fail.
793 	 */
794 	if (strlen(propname) >= ZAP_MAXNAMELEN)
795 		return (ENAMETOOLONG);
796 
797 	err = dsl_dataset_hold(dsname, FTAG, &ds);
798 	if (err)
799 		return (err);
800 
801 	version = spa_version(ds->ds_dir->dd_pool->dp_spa);
802 	if (intsz * numints >= (version < SPA_VERSION_STMF_PROP ?
803 	    ZAP_OLDMAXVALUELEN : ZAP_MAXVALUELEN)) {
804 		dsl_dataset_rele(ds, FTAG);
805 		return (E2BIG);
806 	}
807 	if (dsl_dataset_is_snapshot(ds) &&
808 	    version < SPA_VERSION_SNAP_PROPS) {
809 		dsl_dataset_rele(ds, FTAG);
810 		return (ENOTSUP);
811 	}
812 
813 	psa.psa_name = propname;
814 	psa.psa_source = source;
815 	psa.psa_intsz = intsz;
816 	psa.psa_numints = numints;
817 	psa.psa_value = buf;
818 	psa.psa_effective_value = -1ULL;
819 
820 	err = dsl_sync_task_do(ds->ds_dir->dd_pool,
821 	    NULL, dsl_prop_set_sync, ds, &psa, 2);
822 
823 	dsl_dataset_rele(ds, FTAG);
824 	return (err);
825 }
826 
827 int
828 dsl_props_set(const char *dsname, zprop_source_t source, nvlist_t *props)
829 {
830 	dsl_dataset_t *ds;
831 	uint64_t version;
832 	nvpair_t *elem = NULL;
833 	dsl_props_arg_t pa;
834 	int err;
835 
836 	if (err = dsl_dataset_hold(dsname, FTAG, &ds))
837 		return (err);
838 	/*
839 	 * Do these checks before the syncfunc, since it can't fail.
840 	 */
841 	version = spa_version(ds->ds_dir->dd_pool->dp_spa);
842 	while ((elem = nvlist_next_nvpair(props, elem)) != NULL) {
843 		if (strlen(nvpair_name(elem)) >= ZAP_MAXNAMELEN) {
844 			dsl_dataset_rele(ds, FTAG);
845 			return (ENAMETOOLONG);
846 		}
847 		if (nvpair_type(elem) == DATA_TYPE_STRING) {
848 			char *valstr;
849 			VERIFY(nvpair_value_string(elem, &valstr) == 0);
850 			if (strlen(valstr) >= (version <
851 			    SPA_VERSION_STMF_PROP ?
852 			    ZAP_OLDMAXVALUELEN : ZAP_MAXVALUELEN)) {
853 				dsl_dataset_rele(ds, FTAG);
854 				return (E2BIG);
855 			}
856 		}
857 	}
858 
859 	if (dsl_dataset_is_snapshot(ds) &&
860 	    version < SPA_VERSION_SNAP_PROPS) {
861 		dsl_dataset_rele(ds, FTAG);
862 		return (ENOTSUP);
863 	}
864 
865 	pa.pa_props = props;
866 	pa.pa_source = source;
867 
868 	err = dsl_sync_task_do(ds->ds_dir->dd_pool,
869 	    NULL, dsl_props_set_sync, ds, &pa, 2);
870 
871 	dsl_dataset_rele(ds, FTAG);
872 	return (err);
873 }
874 
875 typedef enum dsl_prop_getflags {
876 	DSL_PROP_GET_INHERITING = 0x1,	/* searching parent of target ds */
877 	DSL_PROP_GET_SNAPSHOT = 0x2,	/* snapshot dataset */
878 	DSL_PROP_GET_LOCAL = 0x4,	/* local properties */
879 	DSL_PROP_GET_RECEIVED = 0x8	/* received properties */
880 } dsl_prop_getflags_t;
881 
882 static int
883 dsl_prop_get_all_impl(objset_t *mos, uint64_t propobj,
884     const char *setpoint, dsl_prop_getflags_t flags, nvlist_t *nv)
885 {
886 	zap_cursor_t zc;
887 	zap_attribute_t za;
888 	int err = 0;
889 
890 	for (zap_cursor_init(&zc, mos, propobj);
891 	    (err = zap_cursor_retrieve(&zc, &za)) == 0;
892 	    zap_cursor_advance(&zc)) {
893 		nvlist_t *propval;
894 		zfs_prop_t prop;
895 		char buf[ZAP_MAXNAMELEN];
896 		char *valstr;
897 		const char *suffix;
898 		const char *propname;
899 		const char *source;
900 
901 		suffix = strchr(za.za_name, '$');
902 
903 		if (suffix == NULL) {
904 			/*
905 			 * Skip local properties if we only want received
906 			 * properties.
907 			 */
908 			if (flags & DSL_PROP_GET_RECEIVED)
909 				continue;
910 
911 			propname = za.za_name;
912 			source = setpoint;
913 		} else if (strcmp(suffix, ZPROP_INHERIT_SUFFIX) == 0) {
914 			/* Skip explicitly inherited entries. */
915 			continue;
916 		} else if (strcmp(suffix, ZPROP_RECVD_SUFFIX) == 0) {
917 			if (flags & DSL_PROP_GET_LOCAL)
918 				continue;
919 
920 			(void) strncpy(buf, za.za_name, (suffix - za.za_name));
921 			buf[suffix - za.za_name] = '\0';
922 			propname = buf;
923 
924 			if (!(flags & DSL_PROP_GET_RECEIVED)) {
925 				/* Skip if locally overridden. */
926 				err = zap_contains(mos, propobj, propname);
927 				if (err == 0)
928 					continue;
929 				if (err != ENOENT)
930 					break;
931 
932 				/* Skip if explicitly inherited. */
933 				valstr = kmem_asprintf("%s%s", propname,
934 				    ZPROP_INHERIT_SUFFIX);
935 				err = zap_contains(mos, propobj, valstr);
936 				strfree(valstr);
937 				if (err == 0)
938 					continue;
939 				if (err != ENOENT)
940 					break;
941 			}
942 
943 			source = ((flags & DSL_PROP_GET_INHERITING) ?
944 			    setpoint : ZPROP_SOURCE_VAL_RECVD);
945 		} else {
946 			/*
947 			 * For backward compatibility, skip suffixes we don't
948 			 * recognize.
949 			 */
950 			continue;
951 		}
952 
953 		prop = zfs_name_to_prop(propname);
954 
955 		/* Skip non-inheritable properties. */
956 		if ((flags & DSL_PROP_GET_INHERITING) && prop != ZPROP_INVAL &&
957 		    !zfs_prop_inheritable(prop))
958 			continue;
959 
960 		/* Skip properties not valid for this type. */
961 		if ((flags & DSL_PROP_GET_SNAPSHOT) && prop != ZPROP_INVAL &&
962 		    !zfs_prop_valid_for_type(prop, ZFS_TYPE_SNAPSHOT))
963 			continue;
964 
965 		/* Skip properties already defined. */
966 		if (nvlist_exists(nv, propname))
967 			continue;
968 
969 		VERIFY(nvlist_alloc(&propval, NV_UNIQUE_NAME, KM_SLEEP) == 0);
970 		if (za.za_integer_length == 1) {
971 			/*
972 			 * String property
973 			 */
974 			char *tmp = kmem_alloc(za.za_num_integers,
975 			    KM_SLEEP);
976 			err = zap_lookup(mos, propobj,
977 			    za.za_name, 1, za.za_num_integers, tmp);
978 			if (err != 0) {
979 				kmem_free(tmp, za.za_num_integers);
980 				break;
981 			}
982 			VERIFY(nvlist_add_string(propval, ZPROP_VALUE,
983 			    tmp) == 0);
984 			kmem_free(tmp, za.za_num_integers);
985 		} else {
986 			/*
987 			 * Integer property
988 			 */
989 			ASSERT(za.za_integer_length == 8);
990 			(void) nvlist_add_uint64(propval, ZPROP_VALUE,
991 			    za.za_first_integer);
992 		}
993 
994 		VERIFY(nvlist_add_string(propval, ZPROP_SOURCE, source) == 0);
995 		VERIFY(nvlist_add_nvlist(nv, propname, propval) == 0);
996 		nvlist_free(propval);
997 	}
998 	zap_cursor_fini(&zc);
999 	if (err == ENOENT)
1000 		err = 0;
1001 	return (err);
1002 }
1003 
1004 /*
1005  * Iterate over all properties for this dataset and return them in an nvlist.
1006  */
1007 static int
1008 dsl_prop_get_all_ds(dsl_dataset_t *ds, nvlist_t **nvp,
1009     dsl_prop_getflags_t flags)
1010 {
1011 	dsl_dir_t *dd = ds->ds_dir;
1012 	dsl_pool_t *dp = dd->dd_pool;
1013 	objset_t *mos = dp->dp_meta_objset;
1014 	int err = 0;
1015 	char setpoint[MAXNAMELEN];
1016 
1017 	VERIFY(nvlist_alloc(nvp, NV_UNIQUE_NAME, KM_SLEEP) == 0);
1018 
1019 	if (dsl_dataset_is_snapshot(ds))
1020 		flags |= DSL_PROP_GET_SNAPSHOT;
1021 
1022 	rw_enter(&dp->dp_config_rwlock, RW_READER);
1023 
1024 	if (ds->ds_phys->ds_props_obj != 0) {
1025 		ASSERT(flags & DSL_PROP_GET_SNAPSHOT);
1026 		dsl_dataset_name(ds, setpoint);
1027 		err = dsl_prop_get_all_impl(mos, ds->ds_phys->ds_props_obj,
1028 		    setpoint, flags, *nvp);
1029 		if (err)
1030 			goto out;
1031 	}
1032 
1033 	for (; dd != NULL; dd = dd->dd_parent) {
1034 		if (dd != ds->ds_dir || (flags & DSL_PROP_GET_SNAPSHOT)) {
1035 			if (flags & (DSL_PROP_GET_LOCAL |
1036 			    DSL_PROP_GET_RECEIVED))
1037 				break;
1038 			flags |= DSL_PROP_GET_INHERITING;
1039 		}
1040 		dsl_dir_name(dd, setpoint);
1041 		err = dsl_prop_get_all_impl(mos, dd->dd_phys->dd_props_zapobj,
1042 		    setpoint, flags, *nvp);
1043 		if (err)
1044 			break;
1045 	}
1046 out:
1047 	rw_exit(&dp->dp_config_rwlock);
1048 	return (err);
1049 }
1050 
1051 boolean_t
1052 dsl_prop_get_hasrecvd(objset_t *os)
1053 {
1054 	dsl_dataset_t *ds = os->os_dsl_dataset;
1055 	int rc;
1056 	uint64_t dummy;
1057 
1058 	rw_enter(&ds->ds_dir->dd_pool->dp_config_rwlock, RW_READER);
1059 	rc = dsl_prop_get_ds(ds, ZPROP_HAS_RECVD, 8, 1, &dummy, NULL);
1060 	rw_exit(&ds->ds_dir->dd_pool->dp_config_rwlock);
1061 	ASSERT(rc != 0 || spa_version(os->os_spa) >= SPA_VERSION_RECVD_PROPS);
1062 	return (rc == 0);
1063 }
1064 
1065 static void
1066 dsl_prop_set_hasrecvd_impl(objset_t *os, zprop_source_t source)
1067 {
1068 	dsl_dataset_t *ds = os->os_dsl_dataset;
1069 	uint64_t dummy = 0;
1070 	dsl_prop_setarg_t psa;
1071 
1072 	if (spa_version(os->os_spa) < SPA_VERSION_RECVD_PROPS)
1073 		return;
1074 
1075 	dsl_prop_setarg_init_uint64(&psa, ZPROP_HAS_RECVD, source, &dummy);
1076 
1077 	(void) dsl_sync_task_do(ds->ds_dir->dd_pool, NULL,
1078 	    dsl_prop_set_sync, ds, &psa, 2);
1079 }
1080 
1081 /*
1082  * Call after successfully receiving properties to ensure that only the first
1083  * receive on or after SPA_VERSION_RECVD_PROPS blows away local properties.
1084  */
1085 void
1086 dsl_prop_set_hasrecvd(objset_t *os)
1087 {
1088 	if (dsl_prop_get_hasrecvd(os)) {
1089 		ASSERT(spa_version(os->os_spa) >= SPA_VERSION_RECVD_PROPS);
1090 		return;
1091 	}
1092 	dsl_prop_set_hasrecvd_impl(os, ZPROP_SRC_LOCAL);
1093 }
1094 
1095 void
1096 dsl_prop_unset_hasrecvd(objset_t *os)
1097 {
1098 	dsl_prop_set_hasrecvd_impl(os, ZPROP_SRC_NONE);
1099 }
1100 
1101 int
1102 dsl_prop_get_all(objset_t *os, nvlist_t **nvp)
1103 {
1104 	return (dsl_prop_get_all_ds(os->os_dsl_dataset, nvp, 0));
1105 }
1106 
1107 int
1108 dsl_prop_get_received(objset_t *os, nvlist_t **nvp)
1109 {
1110 	/*
1111 	 * Received properties are not distinguishable from local properties
1112 	 * until the dataset has received properties on or after
1113 	 * SPA_VERSION_RECVD_PROPS.
1114 	 */
1115 	dsl_prop_getflags_t flags = (dsl_prop_get_hasrecvd(os) ?
1116 	    DSL_PROP_GET_RECEIVED : DSL_PROP_GET_LOCAL);
1117 	return (dsl_prop_get_all_ds(os->os_dsl_dataset, nvp, flags));
1118 }
1119 
1120 void
1121 dsl_prop_nvlist_add_uint64(nvlist_t *nv, zfs_prop_t prop, uint64_t value)
1122 {
1123 	nvlist_t *propval;
1124 	const char *propname = zfs_prop_to_name(prop);
1125 	uint64_t default_value;
1126 
1127 	if (nvlist_lookup_nvlist(nv, propname, &propval) == 0) {
1128 		VERIFY(nvlist_add_uint64(propval, ZPROP_VALUE, value) == 0);
1129 		return;
1130 	}
1131 
1132 	VERIFY(nvlist_alloc(&propval, NV_UNIQUE_NAME, KM_SLEEP) == 0);
1133 	VERIFY(nvlist_add_uint64(propval, ZPROP_VALUE, value) == 0);
1134 	/* Indicate the default source if we can. */
1135 	if (dodefault(propname, 8, 1, &default_value) == 0 &&
1136 	    value == default_value) {
1137 		VERIFY(nvlist_add_string(propval, ZPROP_SOURCE, "") == 0);
1138 	}
1139 	VERIFY(nvlist_add_nvlist(nv, propname, propval) == 0);
1140 	nvlist_free(propval);
1141 }
1142 
1143 void
1144 dsl_prop_nvlist_add_string(nvlist_t *nv, zfs_prop_t prop, const char *value)
1145 {
1146 	nvlist_t *propval;
1147 	const char *propname = zfs_prop_to_name(prop);
1148 
1149 	if (nvlist_lookup_nvlist(nv, propname, &propval) == 0) {
1150 		VERIFY(nvlist_add_string(propval, ZPROP_VALUE, value) == 0);
1151 		return;
1152 	}
1153 
1154 	VERIFY(nvlist_alloc(&propval, NV_UNIQUE_NAME, KM_SLEEP) == 0);
1155 	VERIFY(nvlist_add_string(propval, ZPROP_VALUE, value) == 0);
1156 	VERIFY(nvlist_add_nvlist(nv, propname, propval) == 0);
1157 	nvlist_free(propval);
1158 }
1159