Add '-u' - nomount flag for zfs set

This commit adds '-u' flag for zfs set operation. With this flag,
mountpoint, sharenfs and sharesmb properties can be updated
without actually mounting or sharing the dataset.

Previously, if dataset was unmounted, and mountpoint property was
updated, dataset was not mounted after the update. This behavior
is changed in #15240. We mount the dataset whenever mountpoint
property is updated, regardless if it's mounted or not.

To provide the user with option to keep the dataset unmounted and
still update the mountpoint without mounting the dataset, '-u'
flag can be used.

If any of mountpoint, sharenfs or sharesmb properties are updated
with '-u' flag, the property is set to desired value but the
operation to (re/un)mount and/or (re/un)share the dataset is not
performed and dataset remains as it was before.

Reviewed-by: Alexander Motin <[email protected]>
Reviewed-by: Brian Behlendorf <[email protected]>
Signed-off-by: Umer Saleem <[email protected]>
Closes #15322 

1 files changed, 8 insertions, 0 deletions

diff --git a/include/libzfs.h b/include/libzfs.h
index fa05b7921..6c3669273 100644
--- a/include/libzfs.h
+++ b/include/libzfs.h
@@ -523,6 +523,7 @@ _LIBZFS_H nvlist_t *zfs_valid_proplist(libzfs_handle_t *, zfs_type_t,
 _LIBZFS_H const char *zfs_prop_to_name(zfs_prop_t);
 _LIBZFS_H int zfs_prop_set(zfs_handle_t *, const char *, const char *);
 _LIBZFS_H int zfs_prop_set_list(zfs_handle_t *, nvlist_t *);
+_LIBZFS_H int zfs_prop_set_list_flags(zfs_handle_t *, nvlist_t *, int);
 _LIBZFS_H int zfs_prop_get(zfs_handle_t *, zfs_prop_t, char *, size_t,
     zprop_source_t *, char *, size_t, boolean_t);
 _LIBZFS_H int zfs_prop_get_recvd(zfs_handle_t *, const char *, char *, size_t,
@@ -645,6 +646,13 @@ typedef struct zprop_get_cbdata {
 	vdev_cbdata_t cb_vdevs;
 } zprop_get_cbdata_t;
 
+#define	ZFS_SET_NOMOUNT		1
+
+typedef struct zprop_set_cbdata {
+	int cb_flags;
+	nvlist_t *cb_proplist;
+} zprop_set_cbdata_t;
+
 _LIBZFS_H void zprop_print_one_property(const char *, zprop_get_cbdata_t *,
     const char *, const char *, zprop_source_t, const char *,
     const char *);