libzfs_changelist.c revision 209962
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 2009 Sun Microsystems, Inc.  All rights reserved.
24 * Use is subject to license terms.
25 *
26 * Portions Copyright 2007 Ramprakash Jelari
27 */
28
29#include <libintl.h>
30#include <libuutil.h>
31#include <stddef.h>
32#include <stdlib.h>
33#include <string.h>
34#include <unistd.h>
35#include <zone.h>
36
37#include <libzfs.h>
38
39#include "libzfs_impl.h"
40
41/*
42 * Structure to keep track of dataset state.  Before changing the 'sharenfs' or
43 * 'mountpoint' property, we record whether the filesystem was previously
44 * mounted/shared.  This prior state dictates whether we remount/reshare the
45 * dataset after the property has been changed.
46 *
47 * The interface consists of the following sequence of functions:
48 *
49 * 	changelist_gather()
50 * 	changelist_prefix()
51 * 	< change property >
52 * 	changelist_postfix()
53 * 	changelist_free()
54 *
55 * Other interfaces:
56 *
57 * changelist_remove() - remove a node from a gathered list
58 * changelist_rename() - renames all datasets appropriately when doing a rename
59 * changelist_unshare() - unshares all the nodes in a given changelist
60 * changelist_haszonedchild() - check if there is any child exported to
61 *				a local zone
62 */
63typedef struct prop_changenode {
64	zfs_handle_t		*cn_handle;
65	int			cn_shared;
66	int			cn_mounted;
67	int			cn_zoned;
68	boolean_t		cn_needpost;	/* is postfix() needed? */
69	uu_list_node_t		cn_listnode;
70} prop_changenode_t;
71
72struct prop_changelist {
73	zfs_prop_t		cl_prop;
74	zfs_prop_t		cl_realprop;
75	zfs_prop_t		cl_shareprop;  /* used with sharenfs/sharesmb */
76	uu_list_pool_t		*cl_pool;
77	uu_list_t		*cl_list;
78	boolean_t		cl_waslegacy;
79	boolean_t		cl_allchildren;
80	boolean_t		cl_alldependents;
81	int			cl_mflags;	/* Mount flags */
82	int			cl_gflags;	/* Gather request flags */
83	boolean_t		cl_haszonedchild;
84	boolean_t		cl_sorted;
85};
86
87/*
88 * If the property is 'mountpoint', go through and unmount filesystems as
89 * necessary.  We don't do the same for 'sharenfs', because we can just re-share
90 * with different options without interrupting service. We do handle 'sharesmb'
91 * since there may be old resource names that need to be removed.
92 */
93int
94changelist_prefix(prop_changelist_t *clp)
95{
96	prop_changenode_t *cn;
97	int ret = 0;
98
99	if (clp->cl_prop != ZFS_PROP_MOUNTPOINT &&
100	    clp->cl_prop != ZFS_PROP_SHARESMB)
101		return (0);
102
103	for (cn = uu_list_first(clp->cl_list); cn != NULL;
104	    cn = uu_list_next(clp->cl_list, cn)) {
105
106		/* if a previous loop failed, set the remaining to false */
107		if (ret == -1) {
108			cn->cn_needpost = B_FALSE;
109			continue;
110		}
111
112		/*
113		 * If we are in the global zone, but this dataset is exported
114		 * to a local zone, do nothing.
115		 */
116		if (getzoneid() == GLOBAL_ZONEID && cn->cn_zoned)
117			continue;
118
119		if (ZFS_IS_VOLUME(cn->cn_handle)) {
120			switch (clp->cl_realprop) {
121			case ZFS_PROP_NAME:
122				/*
123				 * If this was a rename, unshare the zvol, and
124				 * remove the /dev/zvol links.
125				 */
126				(void) zfs_unshare_iscsi(cn->cn_handle);
127
128				if (zvol_remove_link(cn->cn_handle->zfs_hdl,
129				    cn->cn_handle->zfs_name) != 0) {
130					ret = -1;
131					cn->cn_needpost = B_FALSE;
132					(void) zfs_share_iscsi(cn->cn_handle);
133				}
134				break;
135
136			case ZFS_PROP_VOLSIZE:
137				/*
138				 * If this was a change to the volume size, we
139				 * need to unshare and reshare the volume.
140				 */
141				(void) zfs_unshare_iscsi(cn->cn_handle);
142				break;
143			}
144		} else {
145			/*
146			 * Do the property specific processing.
147			 */
148			switch (clp->cl_prop) {
149			case ZFS_PROP_MOUNTPOINT:
150				if (zfs_unmount(cn->cn_handle, NULL,
151				    clp->cl_mflags) != 0) {
152					ret = -1;
153					cn->cn_needpost = B_FALSE;
154				}
155				break;
156			case ZFS_PROP_SHARESMB:
157				(void) zfs_unshare_smb(cn->cn_handle, NULL);
158				break;
159			}
160		}
161	}
162
163	if (ret == -1)
164		(void) changelist_postfix(clp);
165
166	return (ret);
167}
168
169/*
170 * If the property is 'mountpoint' or 'sharenfs', go through and remount and/or
171 * reshare the filesystems as necessary.  In changelist_gather() we recorded
172 * whether the filesystem was previously shared or mounted.  The action we take
173 * depends on the previous state, and whether the value was previously 'legacy'.
174 * For non-legacy properties, we only remount/reshare the filesystem if it was
175 * previously mounted/shared.  Otherwise, we always remount/reshare the
176 * filesystem.
177 */
178int
179changelist_postfix(prop_changelist_t *clp)
180{
181	prop_changenode_t *cn;
182	char shareopts[ZFS_MAXPROPLEN];
183	int errors = 0;
184	libzfs_handle_t *hdl;
185
186	/*
187	 * If we're changing the mountpoint, attempt to destroy the underlying
188	 * mountpoint.  All other datasets will have inherited from this dataset
189	 * (in which case their mountpoints exist in the filesystem in the new
190	 * location), or have explicit mountpoints set (in which case they won't
191	 * be in the changelist).
192	 */
193	if ((cn = uu_list_last(clp->cl_list)) == NULL)
194		return (0);
195
196	if (clp->cl_prop == ZFS_PROP_MOUNTPOINT)
197		remove_mountpoint(cn->cn_handle);
198
199	/*
200	 * It is possible that the changelist_prefix() used libshare
201	 * to unshare some entries. Since libshare caches data, an
202	 * attempt to reshare during postfix can fail unless libshare
203	 * is uninitialized here so that it will reinitialize later.
204	 */
205	if (cn->cn_handle != NULL) {
206		hdl = cn->cn_handle->zfs_hdl;
207		assert(hdl != NULL);
208		zfs_uninit_libshare(hdl);
209	}
210
211	/*
212	 * We walk the datasets in reverse, because we want to mount any parent
213	 * datasets before mounting the children.  We walk all datasets even if
214	 * there are errors.
215	 */
216	for (cn = uu_list_last(clp->cl_list); cn != NULL;
217	    cn = uu_list_prev(clp->cl_list, cn)) {
218
219		boolean_t sharenfs;
220		boolean_t sharesmb;
221		boolean_t mounted;
222
223		/*
224		 * If we are in the global zone, but this dataset is exported
225		 * to a local zone, do nothing.
226		 */
227		if (getzoneid() == GLOBAL_ZONEID && cn->cn_zoned)
228			continue;
229
230		/* Only do post-processing if it's required */
231		if (!cn->cn_needpost)
232			continue;
233		cn->cn_needpost = B_FALSE;
234
235		zfs_refresh_properties(cn->cn_handle);
236
237		if (ZFS_IS_VOLUME(cn->cn_handle)) {
238			/*
239			 * If we're doing a rename, recreate the /dev/zvol
240			 * links.
241			 */
242			if (clp->cl_realprop == ZFS_PROP_NAME &&
243			    zvol_create_link(cn->cn_handle->zfs_hdl,
244			    cn->cn_handle->zfs_name) != 0) {
245				errors++;
246			} else if (cn->cn_shared ||
247			    clp->cl_prop == ZFS_PROP_SHAREISCSI) {
248				if (zfs_prop_get(cn->cn_handle,
249				    ZFS_PROP_SHAREISCSI, shareopts,
250				    sizeof (shareopts), NULL, NULL, 0,
251				    B_FALSE) == 0 &&
252				    strcmp(shareopts, "off") == 0) {
253					errors +=
254					    zfs_unshare_iscsi(cn->cn_handle);
255				} else {
256					errors +=
257					    zfs_share_iscsi(cn->cn_handle);
258				}
259			}
260
261			continue;
262		}
263
264		/*
265		 * Remount if previously mounted or mountpoint was legacy,
266		 * or sharenfs or sharesmb  property is set.
267		 */
268		sharenfs = ((zfs_prop_get(cn->cn_handle, ZFS_PROP_SHARENFS,
269		    shareopts, sizeof (shareopts), NULL, NULL, 0,
270		    B_FALSE) == 0) && (strcmp(shareopts, "off") != 0));
271
272		sharesmb = ((zfs_prop_get(cn->cn_handle, ZFS_PROP_SHARESMB,
273		    shareopts, sizeof (shareopts), NULL, NULL, 0,
274		    B_FALSE) == 0) && (strcmp(shareopts, "off") != 0));
275
276		mounted = zfs_is_mounted(cn->cn_handle, NULL);
277
278		if (!mounted && (cn->cn_mounted ||
279		    ((sharenfs || sharesmb || clp->cl_waslegacy) &&
280		    (zfs_prop_get_int(cn->cn_handle,
281		    ZFS_PROP_CANMOUNT) == ZFS_CANMOUNT_ON)))) {
282
283			if (zfs_mount(cn->cn_handle, NULL, 0) != 0)
284				errors++;
285			else
286				mounted = TRUE;
287		}
288
289		/*
290		 * If the file system is mounted we always re-share even
291		 * if the filesystem is currently shared, so that we can
292		 * adopt any new options.
293		 */
294		if (sharenfs && mounted)
295			errors += zfs_share_nfs(cn->cn_handle);
296		else if (cn->cn_shared || clp->cl_waslegacy)
297			errors += zfs_unshare_nfs(cn->cn_handle, NULL);
298		if (sharesmb && mounted)
299			errors += zfs_share_smb(cn->cn_handle);
300		else if (cn->cn_shared || clp->cl_waslegacy)
301			errors += zfs_unshare_smb(cn->cn_handle, NULL);
302	}
303
304	return (errors ? -1 : 0);
305}
306
307/*
308 * Is this "dataset" a child of "parent"?
309 */
310boolean_t
311isa_child_of(const char *dataset, const char *parent)
312{
313	int len;
314
315	len = strlen(parent);
316
317	if (strncmp(dataset, parent, len) == 0 &&
318	    (dataset[len] == '@' || dataset[len] == '/' ||
319	    dataset[len] == '\0'))
320		return (B_TRUE);
321	else
322		return (B_FALSE);
323
324}
325
326/*
327 * If we rename a filesystem, child filesystem handles are no longer valid
328 * since we identify each dataset by its name in the ZFS namespace.  As a
329 * result, we have to go through and fix up all the names appropriately.  We
330 * could do this automatically if libzfs kept track of all open handles, but
331 * this is a lot less work.
332 */
333void
334changelist_rename(prop_changelist_t *clp, const char *src, const char *dst)
335{
336	prop_changenode_t *cn;
337	char newname[ZFS_MAXNAMELEN];
338
339	for (cn = uu_list_first(clp->cl_list); cn != NULL;
340	    cn = uu_list_next(clp->cl_list, cn)) {
341		/*
342		 * Do not rename a clone that's not in the source hierarchy.
343		 */
344		if (!isa_child_of(cn->cn_handle->zfs_name, src))
345			continue;
346
347		/*
348		 * Destroy the previous mountpoint if needed.
349		 */
350		remove_mountpoint(cn->cn_handle);
351
352		(void) strlcpy(newname, dst, sizeof (newname));
353		(void) strcat(newname, cn->cn_handle->zfs_name + strlen(src));
354
355		(void) strlcpy(cn->cn_handle->zfs_name, newname,
356		    sizeof (cn->cn_handle->zfs_name));
357	}
358}
359
360/*
361 * Given a gathered changelist for the 'sharenfs' or 'sharesmb' property,
362 * unshare all the datasets in the list.
363 */
364int
365changelist_unshare(prop_changelist_t *clp, zfs_share_proto_t *proto)
366{
367	prop_changenode_t *cn;
368	int ret = 0;
369
370	if (clp->cl_prop != ZFS_PROP_SHARENFS &&
371	    clp->cl_prop != ZFS_PROP_SHARESMB)
372		return (0);
373
374	for (cn = uu_list_first(clp->cl_list); cn != NULL;
375	    cn = uu_list_next(clp->cl_list, cn)) {
376		if (zfs_unshare_proto(cn->cn_handle, NULL, proto) != 0)
377			ret = -1;
378	}
379
380	return (ret);
381}
382
383/*
384 * Check if there is any child exported to a local zone in a given changelist.
385 * This information has already been recorded while gathering the changelist
386 * via changelist_gather().
387 */
388int
389changelist_haszonedchild(prop_changelist_t *clp)
390{
391	return (clp->cl_haszonedchild);
392}
393
394/*
395 * Remove a node from a gathered list.
396 */
397void
398changelist_remove(prop_changelist_t *clp, const char *name)
399{
400	prop_changenode_t *cn;
401
402	for (cn = uu_list_first(clp->cl_list); cn != NULL;
403	    cn = uu_list_next(clp->cl_list, cn)) {
404
405		if (strcmp(cn->cn_handle->zfs_name, name) == 0) {
406			uu_list_remove(clp->cl_list, cn);
407			zfs_close(cn->cn_handle);
408			free(cn);
409			return;
410		}
411	}
412}
413
414/*
415 * Release any memory associated with a changelist.
416 */
417void
418changelist_free(prop_changelist_t *clp)
419{
420	prop_changenode_t *cn;
421	void *cookie;
422
423	if (clp->cl_list) {
424		cookie = NULL;
425		while ((cn = uu_list_teardown(clp->cl_list, &cookie)) != NULL) {
426			zfs_close(cn->cn_handle);
427			free(cn);
428		}
429
430		uu_list_destroy(clp->cl_list);
431	}
432	if (clp->cl_pool)
433		uu_list_pool_destroy(clp->cl_pool);
434
435	free(clp);
436}
437
438static int
439change_one(zfs_handle_t *zhp, void *data)
440{
441	prop_changelist_t *clp = data;
442	char property[ZFS_MAXPROPLEN];
443	char where[64];
444	prop_changenode_t *cn;
445	zprop_source_t sourcetype;
446	zprop_source_t share_sourcetype;
447
448	/*
449	 * We only want to unmount/unshare those filesystems that may inherit
450	 * from the target filesystem.  If we find any filesystem with a
451	 * locally set mountpoint, we ignore any children since changing the
452	 * property will not affect them.  If this is a rename, we iterate
453	 * over all children regardless, since we need them unmounted in
454	 * order to do the rename.  Also, if this is a volume and we're doing
455	 * a rename, then always add it to the changelist.
456	 */
457
458	if (!(ZFS_IS_VOLUME(zhp) && clp->cl_realprop == ZFS_PROP_NAME) &&
459	    zfs_prop_get(zhp, clp->cl_prop, property,
460	    sizeof (property), &sourcetype, where, sizeof (where),
461	    B_FALSE) != 0) {
462		zfs_close(zhp);
463		return (0);
464	}
465
466	/*
467	 * If we are "watching" sharenfs or sharesmb
468	 * then check out the companion property which is tracked
469	 * in cl_shareprop
470	 */
471	if (clp->cl_shareprop != ZPROP_INVAL &&
472	    zfs_prop_get(zhp, clp->cl_shareprop, property,
473	    sizeof (property), &share_sourcetype, where, sizeof (where),
474	    B_FALSE) != 0) {
475		zfs_close(zhp);
476		return (0);
477	}
478
479	if (clp->cl_alldependents || clp->cl_allchildren ||
480	    sourcetype == ZPROP_SRC_DEFAULT ||
481	    sourcetype == ZPROP_SRC_INHERITED ||
482	    (clp->cl_shareprop != ZPROP_INVAL &&
483	    (share_sourcetype == ZPROP_SRC_DEFAULT ||
484	    share_sourcetype == ZPROP_SRC_INHERITED))) {
485		if ((cn = zfs_alloc(zfs_get_handle(zhp),
486		    sizeof (prop_changenode_t))) == NULL) {
487			zfs_close(zhp);
488			return (-1);
489		}
490
491		cn->cn_handle = zhp;
492		cn->cn_mounted = (clp->cl_gflags & CL_GATHER_MOUNT_ALWAYS) ||
493		    zfs_is_mounted(zhp, NULL);
494		cn->cn_shared = zfs_is_shared(zhp);
495		cn->cn_zoned = zfs_prop_get_int(zhp, ZFS_PROP_ZONED);
496		cn->cn_needpost = B_TRUE;
497
498		/* Indicate if any child is exported to a local zone. */
499		if (getzoneid() == GLOBAL_ZONEID && cn->cn_zoned)
500			clp->cl_haszonedchild = B_TRUE;
501
502		uu_list_node_init(cn, &cn->cn_listnode, clp->cl_pool);
503
504		if (clp->cl_sorted) {
505			uu_list_index_t idx;
506
507			(void) uu_list_find(clp->cl_list, cn, NULL,
508			    &idx);
509			uu_list_insert(clp->cl_list, cn, idx);
510		} else {
511			ASSERT(!clp->cl_alldependents);
512			verify(uu_list_insert_before(clp->cl_list,
513			    uu_list_first(clp->cl_list), cn) == 0);
514		}
515
516		if (!clp->cl_alldependents)
517			return (zfs_iter_children(zhp, change_one, data));
518	} else {
519		zfs_close(zhp);
520	}
521
522	return (0);
523}
524
525/*ARGSUSED*/
526static int
527compare_mountpoints(const void *a, const void *b, void *unused)
528{
529	const prop_changenode_t *ca = a;
530	const prop_changenode_t *cb = b;
531
532	char mounta[MAXPATHLEN];
533	char mountb[MAXPATHLEN];
534
535	boolean_t hasmounta, hasmountb;
536
537	/*
538	 * When unsharing or unmounting filesystems, we need to do it in
539	 * mountpoint order.  This allows the user to have a mountpoint
540	 * hierarchy that is different from the dataset hierarchy, and still
541	 * allow it to be changed.  However, if either dataset doesn't have a
542	 * mountpoint (because it is a volume or a snapshot), we place it at the
543	 * end of the list, because it doesn't affect our change at all.
544	 */
545	hasmounta = (zfs_prop_get(ca->cn_handle, ZFS_PROP_MOUNTPOINT, mounta,
546	    sizeof (mounta), NULL, NULL, 0, B_FALSE) == 0);
547	hasmountb = (zfs_prop_get(cb->cn_handle, ZFS_PROP_MOUNTPOINT, mountb,
548	    sizeof (mountb), NULL, NULL, 0, B_FALSE) == 0);
549
550	if (!hasmounta && hasmountb)
551		return (-1);
552	else if (hasmounta && !hasmountb)
553		return (1);
554	else if (!hasmounta && !hasmountb)
555		return (0);
556	else
557		return (strcmp(mountb, mounta));
558}
559
560/*
561 * Given a ZFS handle and a property, construct a complete list of datasets
562 * that need to be modified as part of this process.  For anything but the
563 * 'mountpoint' and 'sharenfs' properties, this just returns an empty list.
564 * Otherwise, we iterate over all children and look for any datasets that
565 * inherit the property.  For each such dataset, we add it to the list and
566 * mark whether it was shared beforehand.
567 */
568prop_changelist_t *
569changelist_gather(zfs_handle_t *zhp, zfs_prop_t prop, int gather_flags,
570    int mnt_flags)
571{
572	prop_changelist_t *clp;
573	prop_changenode_t *cn;
574	zfs_handle_t *temp;
575	char property[ZFS_MAXPROPLEN];
576	uu_compare_fn_t *compare = NULL;
577
578	if ((clp = zfs_alloc(zhp->zfs_hdl, sizeof (prop_changelist_t))) == NULL)
579		return (NULL);
580
581	/*
582	 * For mountpoint-related tasks, we want to sort everything by
583	 * mountpoint, so that we mount and unmount them in the appropriate
584	 * order, regardless of their position in the hierarchy.
585	 */
586	if (prop == ZFS_PROP_NAME || prop == ZFS_PROP_ZONED ||
587	    prop == ZFS_PROP_MOUNTPOINT || prop == ZFS_PROP_SHARENFS ||
588	    prop == ZFS_PROP_SHARESMB) {
589		compare = compare_mountpoints;
590		clp->cl_sorted = B_TRUE;
591	}
592
593	clp->cl_pool = uu_list_pool_create("changelist_pool",
594	    sizeof (prop_changenode_t),
595	    offsetof(prop_changenode_t, cn_listnode),
596	    compare, 0);
597	if (clp->cl_pool == NULL) {
598		assert(uu_error() == UU_ERROR_NO_MEMORY);
599		(void) zfs_error(zhp->zfs_hdl, EZFS_NOMEM, "internal error");
600		changelist_free(clp);
601		return (NULL);
602	}
603
604	clp->cl_list = uu_list_create(clp->cl_pool, NULL,
605	    clp->cl_sorted ? UU_LIST_SORTED : 0);
606	clp->cl_gflags = gather_flags;
607	clp->cl_mflags = mnt_flags;
608
609	if (clp->cl_list == NULL) {
610		assert(uu_error() == UU_ERROR_NO_MEMORY);
611		(void) zfs_error(zhp->zfs_hdl, EZFS_NOMEM, "internal error");
612		changelist_free(clp);
613		return (NULL);
614	}
615
616	/*
617	 * If this is a rename or the 'zoned' property, we pretend we're
618	 * changing the mountpoint and flag it so we can catch all children in
619	 * change_one().
620	 *
621	 * Flag cl_alldependents to catch all children plus the dependents
622	 * (clones) that are not in the hierarchy.
623	 */
624	if (prop == ZFS_PROP_NAME) {
625		clp->cl_prop = ZFS_PROP_MOUNTPOINT;
626		clp->cl_alldependents = B_TRUE;
627	} else if (prop == ZFS_PROP_ZONED) {
628		clp->cl_prop = ZFS_PROP_MOUNTPOINT;
629		clp->cl_allchildren = B_TRUE;
630	} else if (prop == ZFS_PROP_CANMOUNT) {
631		clp->cl_prop = ZFS_PROP_MOUNTPOINT;
632	} else if (prop == ZFS_PROP_VOLSIZE) {
633		clp->cl_prop = ZFS_PROP_MOUNTPOINT;
634	} else {
635		clp->cl_prop = prop;
636	}
637	clp->cl_realprop = prop;
638
639	if (clp->cl_prop != ZFS_PROP_MOUNTPOINT &&
640	    clp->cl_prop != ZFS_PROP_SHARENFS &&
641	    clp->cl_prop != ZFS_PROP_SHARESMB &&
642	    clp->cl_prop != ZFS_PROP_SHAREISCSI)
643		return (clp);
644
645	/*
646	 * If watching SHARENFS or SHARESMB then
647	 * also watch its companion property.
648	 */
649	if (clp->cl_prop == ZFS_PROP_SHARENFS)
650		clp->cl_shareprop = ZFS_PROP_SHARESMB;
651	else if (clp->cl_prop == ZFS_PROP_SHARESMB)
652		clp->cl_shareprop = ZFS_PROP_SHARENFS;
653
654	if (clp->cl_alldependents) {
655		if (zfs_iter_dependents(zhp, B_TRUE, change_one, clp) != 0) {
656			changelist_free(clp);
657			return (NULL);
658		}
659	} else if (zfs_iter_children(zhp, change_one, clp) != 0) {
660		changelist_free(clp);
661		return (NULL);
662	}
663
664	/*
665	 * We have to re-open ourselves because we auto-close all the handles
666	 * and can't tell the difference.
667	 */
668	if ((temp = zfs_open(zhp->zfs_hdl, zfs_get_name(zhp),
669	    ZFS_TYPE_DATASET)) == NULL) {
670		changelist_free(clp);
671		return (NULL);
672	}
673
674	/*
675	 * Always add ourself to the list.  We add ourselves to the end so that
676	 * we're the last to be unmounted.
677	 */
678	if ((cn = zfs_alloc(zhp->zfs_hdl,
679	    sizeof (prop_changenode_t))) == NULL) {
680		zfs_close(temp);
681		changelist_free(clp);
682		return (NULL);
683	}
684
685	cn->cn_handle = temp;
686	cn->cn_mounted = (clp->cl_gflags & CL_GATHER_MOUNT_ALWAYS) ||
687	    zfs_is_mounted(temp, NULL);
688	cn->cn_shared = zfs_is_shared(temp);
689	cn->cn_zoned = zfs_prop_get_int(zhp, ZFS_PROP_ZONED);
690	cn->cn_needpost = B_TRUE;
691
692	uu_list_node_init(cn, &cn->cn_listnode, clp->cl_pool);
693	if (clp->cl_sorted) {
694		uu_list_index_t idx;
695		(void) uu_list_find(clp->cl_list, cn, NULL, &idx);
696		uu_list_insert(clp->cl_list, cn, idx);
697	} else {
698		verify(uu_list_insert_after(clp->cl_list,
699		    uu_list_last(clp->cl_list), cn) == 0);
700	}
701
702	/*
703	 * If the mountpoint property was previously 'legacy', or 'none',
704	 * record it as the behavior of changelist_postfix() will be different.
705	 */
706	if ((clp->cl_prop == ZFS_PROP_MOUNTPOINT) &&
707	    (zfs_prop_get(zhp, prop, property, sizeof (property),
708	    NULL, NULL, 0, B_FALSE) == 0 &&
709	    (strcmp(property, "legacy") == 0 ||
710	    strcmp(property, "none") == 0))) {
711		/*
712		 * do not automatically mount ex-legacy datasets if
713		 * we specifically set canmount to noauto
714		 */
715		if (zfs_prop_get_int(zhp, ZFS_PROP_CANMOUNT) !=
716		    ZFS_CANMOUNT_NOAUTO)
717			clp->cl_waslegacy = B_TRUE;
718	}
719
720	return (clp);
721}
722