zfs list: Allow more fields in ZFS_ITER_SIMPLE mode

If the fields to be listed and sorted by are constrained to those
populated by dsl_dataset_fast_stat(), then zfs list is much faster,
as it does not need to open each objset and reads its properties.

A previous optimization by Pawel Dawidek
(0cee24064a) took advantage
of this to make listing snapshot names sorted only by name much faster.

However, it was limited to `-o name -s name`, this work extends this
optimization to work with:
  - name
  - guid
  - createtxg
  - numclones
  - inconsistent
  - redacted
  - origin
and could be further extended to any other properties supported by
dsl_dataset_fast_stat() or similar, that do not require extra locking
or reading from disk.

This was committed before (9a9e2e343dfa2af28bf7910de77ae73aa006de62),
but was reverted due to a regression when used with an older kernel.

If the kernel does not populate zc->zc_objset_stats, we now fallback
to getting the properties via the slower interface, to avoid problems
with newer userland and older kernels.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Allan Jude <allan@klarasystems.com>
Closes #14110

lib/libzfs/libzfs.abi

@@ -2925,13 +2925,14 @@
   <abi-instr address-size='64' path='lib/libzfs/libzfs_iter.c' language='LANG_C99'>
     <function-decl name='zfs_iter_filesystems' mangled-name='zfs_iter_filesystems' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='zfs_iter_filesystems'>
       <parameter type-id='9200a744' name='zhp'/>
+      <parameter type-id='95e97e5e' name='flags'/>
       <parameter type-id='d8e49ab9' name='func'/>
       <parameter type-id='eaa32e2f' name='data'/>
       <return type-id='95e97e5e'/>
     </function-decl>
     <function-decl name='zfs_iter_snapshots' mangled-name='zfs_iter_snapshots' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='zfs_iter_snapshots'>
       <parameter type-id='9200a744' name='zhp'/>
-      <parameter type-id='c19b74c3' name='simple'/>
+      <parameter type-id='95e97e5e' name='flags'/>
       <parameter type-id='d8e49ab9' name='func'/>
       <parameter type-id='eaa32e2f' name='data'/>
       <parameter type-id='9c313c2d' name='min_txg'/>
@@ -2940,12 +2941,14 @@
     </function-decl>
     <function-decl name='zfs_iter_bookmarks' mangled-name='zfs_iter_bookmarks' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='zfs_iter_bookmarks'>
       <parameter type-id='9200a744' name='zhp'/>
+      <parameter type-id='95e97e5e' name='flags'/>
       <parameter type-id='d8e49ab9' name='func'/>
       <parameter type-id='eaa32e2f' name='data'/>
       <return type-id='95e97e5e'/>
     </function-decl>
     <function-decl name='zfs_iter_snapshots_sorted' mangled-name='zfs_iter_snapshots_sorted' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='zfs_iter_snapshots_sorted'>
       <parameter type-id='9200a744' name='zhp'/>
+      <parameter type-id='95e97e5e' name='flags'/>
       <parameter type-id='d8e49ab9' name='callback'/>
       <parameter type-id='eaa32e2f' name='data'/>
       <parameter type-id='9c313c2d' name='min_txg'/>
@@ -2954,6 +2957,7 @@
     </function-decl>
     <function-decl name='zfs_iter_snapspec' mangled-name='zfs_iter_snapspec' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='zfs_iter_snapspec'>
       <parameter type-id='9200a744' name='fs_zhp'/>
+      <parameter type-id='95e97e5e' name='flags'/>
       <parameter type-id='80f4b756' name='spec_orig'/>
       <parameter type-id='d8e49ab9' name='func'/>
       <parameter type-id='eaa32e2f' name='arg'/>
@@ -2961,12 +2965,14 @@
     </function-decl>
     <function-decl name='zfs_iter_children' mangled-name='zfs_iter_children' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='zfs_iter_children'>
       <parameter type-id='9200a744' name='zhp'/>
+      <parameter type-id='95e97e5e' name='flags'/>
       <parameter type-id='d8e49ab9' name='func'/>
       <parameter type-id='eaa32e2f' name='data'/>
       <return type-id='95e97e5e'/>
     </function-decl>
     <function-decl name='zfs_iter_dependents' mangled-name='zfs_iter_dependents' visibility='default' binding='global' size-in-bits='64' elf-symbol-id='zfs_iter_dependents'>
       <parameter type-id='9200a744' name='zhp'/>
+      <parameter type-id='95e97e5e' name='flags'/>
       <parameter type-id='c19b74c3' name='allowrecursion'/>
       <parameter type-id='d8e49ab9' name='func'/>
       <parameter type-id='eaa32e2f' name='data'/>

lib/libzfs/libzfs_changelist.c

@@ -552,7 +552,7 @@ change_one(zfs_handle_t *zhp, void *data)
 		}
 
 		if (!clp->cl_alldependents)
-			ret = zfs_iter_children(zhp, change_one, data);
+			ret = zfs_iter_children(zhp, 0, change_one, data);
 
 		/*
 		 * If we added the handle to the changelist, we will re-use it
@@ -721,11 +721,11 @@ changelist_gather(zfs_handle_t *zhp, zfs_prop_t prop, int gather_flags,
 			return (NULL);
 		}
 	} else if (clp->cl_alldependents) {
-		if (zfs_iter_dependents(zhp, B_TRUE, change_one, clp) != 0) {
+		if (zfs_iter_dependents(zhp, 0, B_TRUE, change_one, clp) != 0) {
 			changelist_free(clp);
 			return (NULL);
 		}
-	} else if (zfs_iter_children(zhp, change_one, clp) != 0) {
+	} else if (zfs_iter_children(zhp, 0, change_one, clp) != 0) {
 		changelist_free(clp);
 		return (NULL);
 	}

lib/libzfs/libzfs_crypto.c

@@ -1226,7 +1226,7 @@ load_keys_cb(zfs_handle_t *zhp, void *arg)
 		cb->cb_numfailed++;
 
 out:
-	(void) zfs_iter_filesystems(zhp, load_keys_cb, cb);
+	(void) zfs_iter_filesystems(zhp, 0, load_keys_cb, cb);
 	zfs_close(zhp);
 
 	/* always return 0, since this function is best effort */

lib/libzfs/libzfs_dataset.c

@@ -527,7 +527,30 @@ make_dataset_simple_handle_zc(zfs_handle_t *pzhp, zfs_cmd_t *zc)
 	zhp->zfs_head_type = pzhp->zfs_type;
 	zhp->zfs_type = ZFS_TYPE_SNAPSHOT;
 	zhp->zpool_hdl = zpool_handle(zhp);
-	zhp->zfs_dmustats = zc->zc_objset_stats;
+
+	if (zc->zc_objset_stats.dds_creation_txg != 0) {
+		/* structure assignment */
+		zhp->zfs_dmustats = zc->zc_objset_stats;
+	} else {
+		if (get_stats_ioctl(zhp, zc) == -1) {
+			zcmd_free_nvlists(zc);
+			free(zhp);
+			return (NULL);
+		}
+		if (make_dataset_handle_common(zhp, zc) == -1) {
+			zcmd_free_nvlists(zc);
+			free(zhp);
+			return (NULL);
+		}
+	}
+
+	if (zhp->zfs_dmustats.dds_is_snapshot ||
+	    strchr(zc->zc_name, '@') != NULL)
+		zhp->zfs_type = ZFS_TYPE_SNAPSHOT;
+	else if (zhp->zfs_dmustats.dds_type == DMU_OST_ZVOL)
+		zhp->zfs_type = ZFS_TYPE_VOLUME;
+	else if (zhp->zfs_dmustats.dds_type == DMU_OST_ZFS)
+		zhp->zfs_type = ZFS_TYPE_FILESYSTEM;
 
 	return (zhp);
 }
@@ -734,7 +757,7 @@ zfs_open(libzfs_handle_t *hdl, const char *path, int types)
 		 * Iterate bookmarks to find the right one.
 		 */
 		errno = 0;
-		if ((zfs_iter_bookmarks(pzhp, zfs_open_bookmarks_cb,
+		if ((zfs_iter_bookmarks(pzhp, 0, zfs_open_bookmarks_cb,
 		    &cb_data) == 0) && (cb_data.zhp == NULL)) {
 			(void) zfs_error(hdl, EZFS_NOENT, errbuf);
 			zfs_close(pzhp);
@@ -2086,7 +2109,8 @@ getprop_string(zfs_handle_t *zhp, zfs_prop_t prop, char **source)
 static boolean_t
 zfs_is_recvd_props_mode(zfs_handle_t *zhp)
 {
-	return (zhp->zfs_props == zhp->zfs_recvd_props);
+	return (zhp->zfs_props != NULL &&
+	    zhp->zfs_props == zhp->zfs_recvd_props);
 }
 
 static void
@@ -2288,19 +2312,28 @@ get_numeric_property(zfs_handle_t *zhp, zfs_prop_t prop, zprop_source_t *src,
 		*val = zhp->zfs_dmustats.dds_redacted;
 		break;
 
+	case ZFS_PROP_GUID:
+		if (zhp->zfs_dmustats.dds_guid != 0)
+			*val = zhp->zfs_dmustats.dds_guid;
+		else
+			*val = getprop_uint64(zhp, prop, source);
+		break;
+
 	case ZFS_PROP_CREATETXG:
 		/*
 		 * We can directly read createtxg property from zfs
 		 * handle for Filesystem, Snapshot and ZVOL types.
 		 */
-		if ((zhp->zfs_type == ZFS_TYPE_FILESYSTEM) ||
+		if (((zhp->zfs_type == ZFS_TYPE_FILESYSTEM) ||
 		    (zhp->zfs_type == ZFS_TYPE_SNAPSHOT) ||
-		    (zhp->zfs_type == ZFS_TYPE_VOLUME)) {
+		    (zhp->zfs_type == ZFS_TYPE_VOLUME)) &&
+		    (zhp->zfs_dmustats.dds_creation_txg != 0)) {
 			*val = zhp->zfs_dmustats.dds_creation_txg;
 			break;
+		} else {
+			*val = getprop_uint64(zhp, prop, source);
 		}
 		zfs_fallthrough;
-
 	default:
 		switch (zfs_prop_get_type(prop)) {
 		case PROP_TYPE_NUMBER:
@@ -2443,7 +2476,7 @@ get_clones_cb(zfs_handle_t *zhp, void *arg)
 	}
 
 out:
-	(void) zfs_iter_children(zhp, get_clones_cb, gca);
+	(void) zfs_iter_children(zhp, 0, get_clones_cb, gca);
 	zfs_close(zhp);
 	return (0);
 }
@@ -2728,7 +2761,13 @@ zfs_prop_get(zfs_handle_t *zhp, zfs_prop_t prop, char *propbuf, size_t proplen,
 		break;
 
 	case ZFS_PROP_ORIGIN:
-		str = getprop_string(zhp, prop, &source);
+		if (*zhp->zfs_dmustats.dds_origin != '\0') {
+			str = (char *)&zhp->zfs_dmustats.dds_origin;
+		} else {
+			str = getprop_string(zhp, prop, &source);
+		}
+		if (str == NULL || *str == '\0')
+			str = zfs_prop_default_string(prop);
 		if (str == NULL)
 			return (-1);
 		(void) strlcpy(propbuf, str, proplen);
@@ -3886,7 +3925,7 @@ zfs_check_snap_cb(zfs_handle_t *zhp, void *arg)
 	if (lzc_exists(name))
 		fnvlist_add_boolean(dd->nvl, name);
 
-	rv = zfs_iter_filesystems(zhp, zfs_check_snap_cb, dd);
+	rv = zfs_iter_filesystems(zhp, 0, zfs_check_snap_cb, dd);
 	zfs_close(zhp);
 	return (rv);
 }
@@ -4124,7 +4163,7 @@ zfs_snapshot_cb(zfs_handle_t *zhp, void *arg)
 
 		fnvlist_add_boolean(sd->sd_nvl, name);
 
-		rv = zfs_iter_filesystems(zhp, zfs_snapshot_cb, sd);
+		rv = zfs_iter_filesystems(zhp, 0, zfs_snapshot_cb, sd);
 	}
 	zfs_close(zhp);
 
@@ -4301,7 +4340,7 @@ rollback_destroy(zfs_handle_t *zhp, void *data)
 	rollback_data_t *cbp = data;
 
 	if (zfs_prop_get_int(zhp, ZFS_PROP_CREATETXG) > cbp->cb_create) {
-		cbp->cb_error |= zfs_iter_dependents(zhp, B_FALSE,
+		cbp->cb_error |= zfs_iter_dependents(zhp, 0, B_FALSE,
 		    rollback_destroy_dependent, cbp);
 
 		cbp->cb_error |= zfs_destroy(zhp, B_FALSE);
@@ -4341,10 +4380,10 @@ zfs_rollback(zfs_handle_t *zhp, zfs_handle_t *snap, boolean_t force)
 	if (cb.cb_create > 0)
 		min_txg = cb.cb_create;
 
-	(void) zfs_iter_snapshots(zhp, B_FALSE, rollback_destroy, &cb,
+	(void) zfs_iter_snapshots(zhp, 0, rollback_destroy, &cb,
 	    min_txg, 0);
 
-	(void) zfs_iter_bookmarks(zhp, rollback_destroy, &cb);
+	(void) zfs_iter_bookmarks(zhp, 0, rollback_destroy, &cb);
 
 	if (cb.cb_error)
 		return (-1);
@@ -4925,7 +4964,7 @@ zfs_hold_one(zfs_handle_t *zhp, void *arg)
 		fnvlist_add_string(ha->nvl, name, ha->tag);
 
 	if (ha->recursive)
-		rv = zfs_iter_filesystems(zhp, zfs_hold_one, ha);
+		rv = zfs_iter_filesystems(zhp, 0, zfs_hold_one, ha);
 	zfs_close(zhp);
 	return (rv);
 }
@@ -5056,7 +5095,7 @@ zfs_release_one(zfs_handle_t *zhp, void *arg)
 	}
 
 	if (ha->recursive)
-		rv = zfs_iter_filesystems(zhp, zfs_release_one, ha);
+		rv = zfs_iter_filesystems(zhp, 0, zfs_release_one, ha);
 	zfs_close(zhp);
 	return (rv);
 }

lib/libzfs/libzfs_iter.c

@@ -39,7 +39,8 @@
 #include "libzfs_impl.h"
 
 static int
-zfs_iter_clones(zfs_handle_t *zhp, zfs_iter_f func, void *data)
+zfs_iter_clones(zfs_handle_t *zhp, int flags __maybe_unused, zfs_iter_f func,
+    void *data)
 {
 	nvlist_t *nvl = zfs_get_clones_nvl(zhp);
 	nvpair_t *pair;
@@ -69,6 +70,7 @@ zfs_do_list_ioctl(zfs_handle_t *zhp, int arg, zfs_cmd_t *zc)
 	orig_cookie = zc->zc_cookie;
 top:
 	(void) strlcpy(zc->zc_name, zhp->zfs_name, sizeof (zc->zc_name));
+	zc->zc_objset_stats.dds_creation_txg = 0;
 	rc = zfs_ioctl(zhp->zfs_hdl, arg, zc);
 
 	if (rc == -1) {
@@ -101,7 +103,7 @@ top:
  * Iterate over all child filesystems
  */
 int
-zfs_iter_filesystems(zfs_handle_t *zhp, zfs_iter_f func, void *data)
+zfs_iter_filesystems(zfs_handle_t *zhp, int flags, zfs_iter_f func, void *data)
 {
 	zfs_cmd_t zc = {"\0"};
 	zfs_handle_t *nzhp;
@@ -112,16 +114,21 @@ zfs_iter_filesystems(zfs_handle_t *zhp, zfs_iter_f func, void *data)
 
 	zcmd_alloc_dst_nvlist(zhp->zfs_hdl, &zc, 0);
 
+	if ((flags & ZFS_ITER_SIMPLE) == ZFS_ITER_SIMPLE)
+		zc.zc_simple = B_TRUE;
+
 	while ((ret = zfs_do_list_ioctl(zhp, ZFS_IOC_DATASET_LIST_NEXT,
 	    &zc)) == 0) {
+		if (zc.zc_simple)
+			nzhp = make_dataset_simple_handle_zc(zhp, &zc);
+		else
+			nzhp = make_dataset_handle_zc(zhp->zfs_hdl, &zc);
 		/*
 		 * Silently ignore errors, as the only plausible explanation is
 		 * that the pool has since been removed.
 		 */
-		if ((nzhp = make_dataset_handle_zc(zhp->zfs_hdl,
-		    &zc)) == NULL) {
+		if (nzhp == NULL)
 			continue;
-		}
 
 		if ((ret = func(nzhp, data)) != 0) {
 			zcmd_free_nvlists(&zc);
@@ -136,7 +143,7 @@ zfs_iter_filesystems(zfs_handle_t *zhp, zfs_iter_f func, void *data)
  * Iterate over all snapshots
  */
 int
-zfs_iter_snapshots(zfs_handle_t *zhp, boolean_t simple, zfs_iter_f func,
+zfs_iter_snapshots(zfs_handle_t *zhp, int flags, zfs_iter_f func,
     void *data, uint64_t min_txg, uint64_t max_txg)
 {
 	zfs_cmd_t zc = {"\0"};
@@ -148,7 +155,7 @@ zfs_iter_snapshots(zfs_handle_t *zhp, boolean_t simple, zfs_iter_f func,
 	    zhp->zfs_type == ZFS_TYPE_BOOKMARK)
 		return (0);
 
-	zc.zc_simple = simple;
+	zc.zc_simple = (flags & ZFS_ITER_SIMPLE) != 0;
 
 	zcmd_alloc_dst_nvlist(zhp->zfs_hdl, &zc, 0);
 
@@ -168,7 +175,7 @@ zfs_iter_snapshots(zfs_handle_t *zhp, boolean_t simple, zfs_iter_f func,
 	while ((ret = zfs_do_list_ioctl(zhp, ZFS_IOC_SNAPSHOT_LIST_NEXT,
 	    &zc)) == 0) {
 
-		if (simple)
+		if (zc.zc_simple)
 			nzhp = make_dataset_simple_handle_zc(zhp, &zc);
 		else
 			nzhp = make_dataset_handle_zc(zhp->zfs_hdl, &zc);
@@ -190,7 +197,8 @@ zfs_iter_snapshots(zfs_handle_t *zhp, boolean_t simple, zfs_iter_f func,
  * Iterate over all bookmarks
  */
 int
-zfs_iter_bookmarks(zfs_handle_t *zhp, zfs_iter_f func, void *data)
+zfs_iter_bookmarks(zfs_handle_t *zhp, int flags __maybe_unused,
+    zfs_iter_f func, void *data)
 {
 	zfs_handle_t *nzhp;
 	nvlist_t *props = NULL;
@@ -297,8 +305,8 @@ zfs_snapshot_compare(const void *larg, const void *rarg)
 }
 
 int
-zfs_iter_snapshots_sorted(zfs_handle_t *zhp, zfs_iter_f callback, void *data,
-    uint64_t min_txg, uint64_t max_txg)
+zfs_iter_snapshots_sorted(zfs_handle_t *zhp, int flags, zfs_iter_f callback,
+    void *data, uint64_t min_txg, uint64_t max_txg)
 {
 	int ret = 0;
 	zfs_node_t *node;
@@ -308,7 +316,7 @@ zfs_iter_snapshots_sorted(zfs_handle_t *zhp, zfs_iter_f callback, void *data,
 	avl_create(&avl, zfs_snapshot_compare,
 	    sizeof (zfs_node_t), offsetof(zfs_node_t, zn_avlnode));
 
-	ret = zfs_iter_snapshots(zhp, B_FALSE, zfs_sort_snaps, &avl, min_txg,
+	ret = zfs_iter_snapshots(zhp, flags, zfs_sort_snaps, &avl, min_txg,
 	    max_txg);
 
 	for (node = avl_first(&avl); node != NULL; node = AVL_NEXT(&avl, node))
@@ -371,7 +379,7 @@ snapspec_cb(zfs_handle_t *zhp, void *arg)
  * return ENOENT at the end.
  */
 int
-zfs_iter_snapspec(zfs_handle_t *fs_zhp, const char *spec_orig,
+zfs_iter_snapspec(zfs_handle_t *fs_zhp, int flags, const char *spec_orig,
     zfs_iter_f func, void *arg)
 {
 	char *buf, *comma_separated, *cp;
@@ -411,7 +419,7 @@ zfs_iter_snapspec(zfs_handle_t *fs_zhp, const char *spec_orig,
 				}
 			}
 
-			err = zfs_iter_snapshots_sorted(fs_zhp,
+			err = zfs_iter_snapshots_sorted(fs_zhp, flags,
 			    snapspec_cb, &ssa, 0, 0);
 			if (ret == 0)
 				ret = err;
@@ -448,14 +456,14 @@ zfs_iter_snapspec(zfs_handle_t *fs_zhp, const char *spec_orig,
  * and as close as possible.
  */
 int
-zfs_iter_children(zfs_handle_t *zhp, zfs_iter_f func, void *data)
+zfs_iter_children(zfs_handle_t *zhp, int flags, zfs_iter_f func, void *data)
 {
 	int ret;
 
-	if ((ret = zfs_iter_snapshots(zhp, B_FALSE, func, data, 0, 0)) != 0)
+	if ((ret = zfs_iter_snapshots(zhp, flags, func, data, 0, 0)) != 0)
 		return (ret);
 
-	return (zfs_iter_filesystems(zhp, func, data));
+	return (zfs_iter_filesystems(zhp, flags, func, data));
 }
 
 
@@ -466,6 +474,7 @@ typedef struct iter_stack_frame {
 
 typedef struct iter_dependents_arg {
 	boolean_t first;
+	int flags;
 	boolean_t allowrecursion;
 	iter_stack_frame_t *stack;
 	zfs_iter_f func;
@@ -481,7 +490,7 @@ iter_dependents_cb(zfs_handle_t *zhp, void *arg)
 	ida->first = B_FALSE;
 
 	if (zhp->zfs_type == ZFS_TYPE_SNAPSHOT) {
-		err = zfs_iter_clones(zhp, iter_dependents_cb, ida);
+		err = zfs_iter_clones(zhp, ida->flags, iter_dependents_cb, ida);
 	} else if (zhp->zfs_type != ZFS_TYPE_BOOKMARK) {
 		iter_stack_frame_t isf;
 		iter_stack_frame_t *f;
@@ -515,9 +524,10 @@ iter_dependents_cb(zfs_handle_t *zhp, void *arg)
 		isf.zhp = zhp;
 		isf.next = ida->stack;
 		ida->stack = &isf;
-		err = zfs_iter_filesystems(zhp, iter_dependents_cb, ida);
+		err = zfs_iter_filesystems(zhp, ida->flags,
+		    iter_dependents_cb, ida);
 		if (err == 0)
-			err = zfs_iter_snapshots(zhp, B_FALSE,
+			err = zfs_iter_snapshots(zhp, ida->flags,
 			    iter_dependents_cb, ida, 0, 0);
 		ida->stack = isf.next;
 	}
@@ -531,10 +541,11 @@ iter_dependents_cb(zfs_handle_t *zhp, void *arg)
 }
 
 int
-zfs_iter_dependents(zfs_handle_t *zhp, boolean_t allowrecursion,
+zfs_iter_dependents(zfs_handle_t *zhp, int flags, boolean_t allowrecursion,
     zfs_iter_f func, void *data)
 {
 	iter_dependents_arg_t ida;
+	ida.flags = flags;
 	ida.allowrecursion = allowrecursion;
 	ida.stack = NULL;
 	ida.func = func;

lib/libzfs/libzfs_mount.c

@@ -940,7 +940,7 @@ zfs_iter_cb(zfs_handle_t *zhp, void *data)
 	}
 
 	libzfs_add_handle(cbp, zhp);
-	if (zfs_iter_filesystems(zhp, zfs_iter_cb, cbp) != 0) {
+	if (zfs_iter_filesystems(zhp, 0, zfs_iter_cb, cbp) != 0) {
 		zfs_close(zhp);
 		return (-1);
 	}
@@ -1289,7 +1289,7 @@ zpool_enable_datasets(zpool_handle_t *zhp, const char *mntopts, int flags)
 	 * over all child filesystems.
 	 */
 	libzfs_add_handle(&cb, zfsp);
-	if (zfs_iter_filesystems(zfsp, zfs_iter_cb, &cb) != 0)
+	if (zfs_iter_filesystems(zfsp, 0, zfs_iter_cb, &cb) != 0)
 		goto out;
 
 	/*

lib/libzfs/libzfs_sendrecv.c

@@ -616,10 +616,10 @@ send_iterate_fs(zfs_handle_t *zhp, void *arg)
 			min_txg = fromsnap_txg;
 		if (!sd->replicate && tosnap_txg != 0)
 			max_txg = tosnap_txg;
-		(void) zfs_iter_snapshots_sorted(zhp, send_iterate_snap, sd,
+		(void) zfs_iter_snapshots_sorted(zhp, 0, send_iterate_snap, sd,
 		    min_txg, max_txg);
 	} else {
-		char snapname[MAXPATHLEN];
+		char snapname[MAXPATHLEN] = { 0 };
 		zfs_handle_t *snap;
 
 		(void) snprintf(snapname, sizeof (snapname), "%s@%s",
@@ -659,7 +659,7 @@ send_iterate_fs(zfs_handle_t *zhp, void *arg)
 
 	/* Iterate over children. */
 	if (sd->recursive)
-		rv = zfs_iter_filesystems(zhp, send_iterate_fs, sd);
+		rv = zfs_iter_filesystems(zhp, 0, send_iterate_fs, sd);
 
 out:
 	/* Restore saved fields. */
@@ -1274,7 +1274,7 @@ dump_filesystem(zfs_handle_t *zhp, send_dump_data_t *sdd)
 				    zhp->zfs_name, sdd->tosnap);
 			}
 		}
-		rv = zfs_iter_snapshots_sorted(zhp, dump_snapshot, sdd,
+		rv = zfs_iter_snapshots_sorted(zhp, 0, dump_snapshot, sdd,
 		    min_txg, max_txg);
 	} else {
 		char snapname[MAXPATHLEN] = { 0 };
@@ -3125,9 +3125,9 @@ guid_to_name_cb(zfs_handle_t *zhp, void *arg)
 		return (EEXIST);
 	}
 
-	err = zfs_iter_children(zhp, guid_to_name_cb, gtnd);
+	err = zfs_iter_children(zhp, 0, guid_to_name_cb, gtnd);
 	if (err != EEXIST && gtnd->bookmark_ok)
-		err = zfs_iter_bookmarks(zhp, guid_to_name_cb, gtnd);
+		err = zfs_iter_bookmarks(zhp, 0, guid_to_name_cb, gtnd);
 	zfs_close(zhp);
 	return (err);
 }
@@ -3181,9 +3181,10 @@ guid_to_name_redact_snaps(libzfs_handle_t *hdl, const char *parent,
 			continue;
 		int err = guid_to_name_cb(zfs_handle_dup(zhp), &gtnd);
 		if (err != EEXIST)
-			err = zfs_iter_children(zhp, guid_to_name_cb, &gtnd);
+			err = zfs_iter_children(zhp, 0, guid_to_name_cb, &gtnd);
 		if (err != EEXIST && bookmark_ok)
-			err = zfs_iter_bookmarks(zhp, guid_to_name_cb, &gtnd);
+			err = zfs_iter_bookmarks(zhp, 0, guid_to_name_cb,
+			    &gtnd);
 		zfs_close(zhp);
 		if (err == EEXIST)
 			return (0);