staging: lustre: lmv: allow cross-MDT rename and link

Remove checks for cross-MDT operation, so cross-MDT
rename and link will be allowed.

Remove obsolete locality parameters in MDT lock API after all of
cross-MDT operations are allowed.

This is the client side changed only so the upstream
client can support this.
Signed-off-by: wang di <di.wang@intel.com>
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-3537
Reviewed-on: http://review.whamcloud.com/12282Reviewed-by: James Simmons <uja.ornl@yahoo.com>
Reviewed-by: Lai Siyao <lai.siyao@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/lmv/lmv_obd.c

@@ -1903,7 +1903,10 @@ static int lmv_rename(struct obd_export *exp, struct md_op_data *op_data,
 {
 	struct obd_device       *obd = exp->exp_obd;
 	struct lmv_obd	  *lmv = &obd->u.lmv;
+	struct obd_export *target_exp;
 	struct lmv_tgt_desc     *src_tgt;
+	struct lmv_tgt_desc *tgt_tgt;
+	struct mdt_body *body;
 	int			rc;
 
 	LASSERT(oldlen != 0);
@@ -1943,6 +1946,10 @@ static int lmv_rename(struct obd_export *exp, struct md_op_data *op_data,
 		if (rc)
 			return rc;
 		src_tgt = lmv_find_target(lmv, &op_data->op_fid3);
+		if (IS_ERR(src_tgt))
+			return PTR_ERR(src_tgt);
+
+		target_exp = src_tgt->ltd_exp;
 	} else {
 		if (op_data->op_mea1) {
 			struct lmv_stripe_md *lsm = op_data->op_mea1;
@@ -1951,29 +1958,27 @@ static int lmv_rename(struct obd_export *exp, struct md_op_data *op_data,
 							     oldlen,
 							     &op_data->op_fid1,
 							     &op_data->op_mds);
-			if (IS_ERR(src_tgt))
-				return PTR_ERR(src_tgt);
 		} else {
 			src_tgt = lmv_find_target(lmv, &op_data->op_fid1);
+		}
 		if (IS_ERR(src_tgt))
 			return PTR_ERR(src_tgt);
 
-			op_data->op_mds = src_tgt->ltd_idx;
-		}
-
 		if (op_data->op_mea2) {
 			struct lmv_stripe_md *lsm = op_data->op_mea2;
-			const struct lmv_oinfo *oinfo;
 
-			oinfo = lsm_name_to_stripe_info(lsm, new, newlen);
-			if (IS_ERR(oinfo))
-				return PTR_ERR(oinfo);
-
-			op_data->op_fid2 = oinfo->lmo_fid;
+			tgt_tgt = lmv_locate_target_for_name(lmv, lsm, new,
+							     newlen,
+							     &op_data->op_fid2,
+							     &op_data->op_mds);
+		} else {
+			tgt_tgt = lmv_find_target(lmv, &op_data->op_fid2);
 		}
+		if (IS_ERR(tgt_tgt))
+			return PTR_ERR(tgt_tgt);
+
+		target_exp = tgt_tgt->ltd_exp;
 	}
-	if (IS_ERR(src_tgt))
-		return PTR_ERR(src_tgt);
 
 	/*
 	 * LOOKUP lock on src child (fid3) should also be cancelled for
@@ -2014,20 +2019,52 @@ static int lmv_rename(struct obd_export *exp, struct md_op_data *op_data,
 			return rc;
 	}
 
+retry_rename:
 	/*
 	 * Cancel all the locks on tgt child (fid4).
 	 */
-	if (fid_is_sane(&op_data->op_fid4))
+	if (fid_is_sane(&op_data->op_fid4)) {
+		struct lmv_tgt_desc *tgt;
+
 		rc = lmv_early_cancel(exp, NULL, op_data, src_tgt->ltd_idx,
 				      LCK_EX, MDS_INODELOCK_FULL,
 				      MF_MDC_CANCEL_FID4);
+		if (rc)
+			return rc;
 
-	CDEBUG(D_INODE, DFID":m%d to "DFID"\n", PFID(&op_data->op_fid1),
-	       op_data->op_mds, PFID(&op_data->op_fid2));
+		tgt = lmv_find_target(lmv, &op_data->op_fid4);
+		if (IS_ERR(tgt))
+			return PTR_ERR(tgt);
 
-	rc = md_rename(src_tgt->ltd_exp, op_data, old, oldlen,
-		       new, newlen, request);
+		/*
+		 * Since the target child might be destroyed, and it might
+		 * become orphan, and we can only check orphan on the local
+		 * MDT right now, so we send rename request to the MDT where
+		 * target child is located. If target child does not exist,
+		 * then it will send the request to the target parent
+		 */
+		target_exp = tgt->ltd_exp;
+	}
+
+	rc = md_rename(target_exp, op_data, old, oldlen, new, newlen, request);
+	if (rc && rc != -EREMOTE)
 		return rc;
+
+	body = req_capsule_server_get(&(*request)->rq_pill, &RMF_MDT_BODY);
+	if (!body)
+		return -EPROTO;
+
+	/* Not cross-ref case, just get out of here. */
+	if (likely(!(body->mbo_valid & OBD_MD_MDS)))
+		return rc;
+
+	CDEBUG(D_INODE, "%s: try rename to another MDT for " DFID "\n",
+	       exp->exp_obd->obd_name, PFID(&body->mbo_fid1));
+
+	op_data->op_fid4 = body->mbo_fid1;
+	ptlrpc_req_finished(*request);
+	*request = NULL;
+	goto retry_rename;
 }
 
 static int lmv_setattr(struct obd_export *exp, struct md_op_data *op_data,