1*8d6e79d3SJon Maloy /* 2*8d6e79d3SJon Maloy * include/net/tipc.h: Include file for TIPC message header routines 3*8d6e79d3SJon Maloy * 4*8d6e79d3SJon Maloy * Copyright (c) 2017 Ericsson AB 5*8d6e79d3SJon Maloy * All rights reserved. 6*8d6e79d3SJon Maloy * 7*8d6e79d3SJon Maloy * Redistribution and use in source and binary forms, with or without 8*8d6e79d3SJon Maloy * modification, are permitted provided that the following conditions are met: 9*8d6e79d3SJon Maloy * 10*8d6e79d3SJon Maloy * 1. Redistributions of source code must retain the above copyright 11*8d6e79d3SJon Maloy * notice, this list of conditions and the following disclaimer. 12*8d6e79d3SJon Maloy * 2. Redistributions in binary form must reproduce the above copyright 13*8d6e79d3SJon Maloy * notice, this list of conditions and the following disclaimer in the 14*8d6e79d3SJon Maloy * documentation and/or other materials provided with the distribution. 15*8d6e79d3SJon Maloy * 3. Neither the names of the copyright holders nor the names of its 16*8d6e79d3SJon Maloy * contributors may be used to endorse or promote products derived from 17*8d6e79d3SJon Maloy * this software without specific prior written permission. 18*8d6e79d3SJon Maloy * 19*8d6e79d3SJon Maloy * Alternatively, this software may be distributed under the terms of the 20*8d6e79d3SJon Maloy * GNU General Public License ("GPL") version 2 as published by the Free 21*8d6e79d3SJon Maloy * Software Foundation. 22*8d6e79d3SJon Maloy * 23*8d6e79d3SJon Maloy * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 24*8d6e79d3SJon Maloy * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25*8d6e79d3SJon Maloy * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26*8d6e79d3SJon Maloy * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 27*8d6e79d3SJon Maloy * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 28*8d6e79d3SJon Maloy * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 29*8d6e79d3SJon Maloy * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 30*8d6e79d3SJon Maloy * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 31*8d6e79d3SJon Maloy * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 32*8d6e79d3SJon Maloy * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 33*8d6e79d3SJon Maloy * POSSIBILITY OF SUCH DAMAGE. 34*8d6e79d3SJon Maloy */ 35*8d6e79d3SJon Maloy 36*8d6e79d3SJon Maloy #ifndef _TIPC_HDR_H 37*8d6e79d3SJon Maloy #define _TIPC_HDR_H 38*8d6e79d3SJon Maloy 39*8d6e79d3SJon Maloy #include <linux/random.h> 40*8d6e79d3SJon Maloy 41*8d6e79d3SJon Maloy #define KEEPALIVE_MSG_MASK 0x0e080000 /* LINK_PROTOCOL + MSG_IS_KEEPALIVE */ 42*8d6e79d3SJon Maloy 43*8d6e79d3SJon Maloy struct tipc_basic_hdr { 44*8d6e79d3SJon Maloy __be32 w[4]; 45*8d6e79d3SJon Maloy }; 46*8d6e79d3SJon Maloy 47*8d6e79d3SJon Maloy static inline u32 tipc_hdr_rps_key(struct tipc_basic_hdr *hdr) 48*8d6e79d3SJon Maloy { 49*8d6e79d3SJon Maloy u32 w0 = ntohl(hdr->w[0]); 50*8d6e79d3SJon Maloy bool keepalive_msg = (w0 & KEEPALIVE_MSG_MASK) == KEEPALIVE_MSG_MASK; 51*8d6e79d3SJon Maloy int key; 52*8d6e79d3SJon Maloy 53*8d6e79d3SJon Maloy /* Return source node identity as key */ 54*8d6e79d3SJon Maloy if (likely(!keepalive_msg)) 55*8d6e79d3SJon Maloy return hdr->w[3]; 56*8d6e79d3SJon Maloy 57*8d6e79d3SJon Maloy /* Spread PROBE/PROBE_REPLY messages across the cores */ 58*8d6e79d3SJon Maloy get_random_bytes(&key, sizeof(key)); 59*8d6e79d3SJon Maloy return key; 60*8d6e79d3SJon Maloy } 61*8d6e79d3SJon Maloy 62*8d6e79d3SJon Maloy #endif 63