+
+/**
+ * If request has a new allocated XID (new request or EINPROGRESS resend),
+ * use this XID as matchbits of bulk, otherwise allocate a new matchbits for
+ * request to ensure previous bulk fails and avoid problems with lost replies
+ * and therefore several transfers landing into the same buffer from different
+ * sending attempts.
+ */
+void ptlrpc_set_bulk_mbits(struct ptlrpc_request *req)
+{
+ struct ptlrpc_bulk_desc *bd = req->rq_bulk;
+
+ LASSERT(bd != NULL);
+
+ if (!req->rq_resend || req->rq_nr_resend != 0) {
+ /* this request has a new xid, just use it as bulk matchbits */
+ req->rq_mbits = req->rq_xid;
+
+ } else { /* needs to generate a new matchbits for resend */
+ __u64 old_mbits = req->rq_mbits;
+
+ if ((bd->bd_import->imp_connect_data.ocd_connect_flags &
+ OBD_CONNECT_BULK_MBITS) != 0)
+ req->rq_mbits = ptlrpc_next_xid();
+ else /* old version transfers rq_xid to peer as matchbits */
+ req->rq_mbits = req->rq_xid = ptlrpc_next_xid();
+
+ CDEBUG(D_HA, "resend bulk old x"LPU64" new x"LPU64"\n",
+ old_mbits, req->rq_mbits);
+ }
+
+ /* For multi-bulk RPCs, rq_mbits is the last mbits needed for bulks so
+ * that server can infer the number of bulks that were prepared,
+ * see LU-1431 */
+ req->rq_mbits += ((bd->bd_iov_count + LNET_MAX_IOV - 1) /
+ LNET_MAX_IOV) - 1;
+}