3 files changed, 29 insertions, 7 deletions

diff --git a/usr/src/lib/libzfs/common/libzfs_changelist.c b/usr/src/lib/libzfs/common/libzfs_changelist.c
index 3d99982bcb..80e8409af3 100644
--- a/usr/src/lib/libzfs/common/libzfs_changelist.c
+++ b/usr/src/lib/libzfs/common/libzfs_changelist.c
@@ -695,8 +695,16 @@ changelist_gather(zfs_handle_t *zhp, zfs_prop_t prop, int flags)
 	if ((clp->cl_prop == ZFS_PROP_MOUNTPOINT) &&
 	    (zfs_prop_get(zhp, prop, property, sizeof (property),
 	    NULL, NULL, 0, B_FALSE) == 0 &&
-	    (strcmp(property, "legacy") == 0 || strcmp(property, "none") == 0)))
-		clp->cl_waslegacy = B_TRUE;
+	    (strcmp(property, "legacy") == 0 ||
+	    strcmp(property, "none") == 0))) {
+		/*
+		 * do not automatically mount ex-legacy datasets if
+		 * we specifically set canmount to noauto
+		 */
+		if (zfs_prop_get_int(zhp, ZFS_PROP_CANMOUNT) !=
+		    ZFS_CANMOUNT_NOAUTO)
+			clp->cl_waslegacy = B_TRUE;
+	}
 
 	return (clp);
 }
diff --git a/usr/src/lib/libzfs/common/libzfs_dataset.c b/usr/src/lib/libzfs/common/libzfs_dataset.c
index d1d058d3e4..a83226182d 100644
--- a/usr/src/lib/libzfs/common/libzfs_dataset.c
+++ b/usr/src/lib/libzfs/common/libzfs_dataset.c
@@ -1720,6 +1720,7 @@ zfs_prop_set(zfs_handle_t *zhp, const char *propname, const char *propval)
 	libzfs_handle_t *hdl = zhp->zfs_hdl;
 	nvlist_t *nvl = NULL, *realprops;
 	zfs_prop_t prop;
+	int do_prefix = 1;
 
 	(void) snprintf(errbuf, sizeof (errbuf),
 	    dgettext(TEXT_DOMAIN, "cannot set property for '%s'"),
@@ -1751,8 +1752,13 @@ zfs_prop_set(zfs_handle_t *zhp, const char *propname, const char *propval)
 		goto error;
 	}
 
-	if ((ret = changelist_prefix(cl)) != 0)
-		goto error;
+
+	/* do not unmount dataset if canmount is being set to noauto */
+	if (prop == ZFS_PROP_CANMOUNT && *propval == ZFS_CANMOUNT_NOAUTO)
+		do_prefix = 0;
+
+	if (do_prefix && (ret = changelist_prefix(cl)) != 0)
+			goto error;
 
 	/*
 	 * Execute the corresponding ioctl() to set this property.
@@ -1827,11 +1833,14 @@ zfs_prop_set(zfs_handle_t *zhp, const char *propname, const char *propval)
 			(void) zfs_standard_error(hdl, errno, errbuf);
 		}
 	} else {
+		if (do_prefix)
+			ret = changelist_postfix(cl);
+
 		/*
 		 * Refresh the statistics so the new property value
 		 * is reflected.
 		 */
-		if ((ret = changelist_postfix(cl)) == 0)
+		if (ret == 0)
 			(void) get_stats(zhp);
 	}
 
@@ -2096,7 +2105,7 @@ get_numeric_property(zfs_handle_t *zhp, zfs_prop_t prop, zprop_source_t *src,
 
 	case ZFS_PROP_CANMOUNT:
 		*val = getprop_uint64(zhp, prop, source);
-		if (*val == 0)
+		if (*val != ZFS_CANMOUNT_ON)
 			*source = zhp->zfs_name;
 		else
 			*source = "";	/* default */
diff --git a/usr/src/lib/libzfs/common/libzfs_mount.c b/usr/src/lib/libzfs/common/libzfs_mount.c
index a53cc003fb..c182a841bd 100644
--- a/usr/src/lib/libzfs/common/libzfs_mount.c
+++ b/usr/src/lib/libzfs/common/libzfs_mount.c
@@ -285,7 +285,7 @@ zfs_is_mountable(zfs_handle_t *zhp, char *buf, size_t buflen,
 	    strcmp(buf, ZFS_MOUNTPOINT_LEGACY) == 0)
 		return (B_FALSE);
 
-	if (!zfs_prop_get_int(zhp, ZFS_PROP_CANMOUNT))
+	if (zfs_prop_get_int(zhp, ZFS_PROP_CANMOUNT) == ZFS_CANMOUNT_OFF)
 		return (B_FALSE);
 
 	if (zfs_prop_get_int(zhp, ZFS_PROP_ZONED) &&
@@ -1103,6 +1103,11 @@ mount_cb(zfs_handle_t *zhp, void *data)
 		return (0);
 	}
 
+	if (zfs_prop_get_int(zhp, ZFS_PROP_CANMOUNT) == ZFS_CANMOUNT_NOAUTO) {
+		zfs_close(zhp);
+		return (0);
+	}
+
 	if (cbp->cb_alloc == cbp->cb_used) {
 		void *ptr;