ZFS_SYNC_DISABLED
{ "disabled", ZFS_SYNC_DISABLED },
newval == ZFS_SYNC_DISABLED);
zfsvfs->z_os->os_sync = ZFS_SYNC_DISABLED;
if (zfsvfs->z_os->os_sync != ZFS_SYNC_DISABLED) {
if (zilog->zl_sync == ZFS_SYNC_DISABLED)
if (zilog->zl_sync == ZFS_SYNC_DISABLED)