staging: lustre: llite: default dir stripe index only for mkdir

Default dir stripe index should only work during mkdir,
otherwise it will cause other open/create request being
sent to the wrong MDT.
Signed-off-by: wang di <di.wang@intel.com>
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-6373
Reviewed-on: http://review.whamcloud.com/14096Reviewed-by: Alex Zhuravlev <alexey.zhuravlev@intel.com>
Reviewed-by: Fan Yong <fan.yong@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: James Simmons <jsimmons@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/lustre/lustre/llite/llite_lib.c

@@ -2269,6 +2269,7 @@ struct md_op_data *ll_prep_md_op_data(struct md_op_data *op_data,
 	op_data->op_default_stripe_offset = -1;
 	if (S_ISDIR(i1->i_mode)) {
 		op_data->op_mea1 = ll_i2info(i1)->lli_lsm_md;
+		if (opc == LUSTRE_OPC_MKDIR)
 			op_data->op_default_stripe_offset =
 				ll_i2info(i1)->lli_def_stripe_offset;
 	}