1 /* 2 * net/tipc/subscr.c: TIPC network topology service 3 * 4 * Copyright (c) 2000-2017, Ericsson AB 5 * Copyright (c) 2005-2007, 2010-2013, Wind River Systems 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions are met: 10 * 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the names of the copyright holders nor the names of its 17 * contributors may be used to endorse or promote products derived from 18 * this software without specific prior written permission. 19 * 20 * Alternatively, this software may be distributed under the terms of the 21 * GNU General Public License ("GPL") version 2 as published by the Free 22 * Software Foundation. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 25 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 28 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 29 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 31 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 32 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 33 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 34 * POSSIBILITY OF SUCH DAMAGE. 35 */ 36 37 #include "core.h" 38 #include "name_table.h" 39 #include "subscr.h" 40 41 static void tipc_sub_send_event(struct tipc_subscription *sub, 42 u32 found_lower, u32 found_upper, 43 u32 event, u32 port, u32 node) 44 { 45 struct tipc_event *evt = &sub->evt; 46 47 if (sub->inactive) 48 return; 49 tipc_evt_write(evt, event, event); 50 tipc_evt_write(evt, found_lower, found_lower); 51 tipc_evt_write(evt, found_upper, found_upper); 52 tipc_evt_write(evt, port.ref, port); 53 tipc_evt_write(evt, port.node, node); 54 tipc_topsrv_queue_evt(sub->net, sub->conid, event, evt); 55 } 56 57 /** 58 * tipc_sub_check_overlap - test for subscription overlap with the 59 * given values 60 * 61 * Returns 1 if there is overlap, otherwise 0. 62 */ 63 int tipc_sub_check_overlap(struct tipc_name_seq *seq, u32 found_lower, 64 u32 found_upper) 65 { 66 if (found_lower < seq->lower) 67 found_lower = seq->lower; 68 if (found_upper > seq->upper) 69 found_upper = seq->upper; 70 if (found_lower > found_upper) 71 return 0; 72 return 1; 73 } 74 75 void tipc_sub_report_overlap(struct tipc_subscription *sub, 76 u32 found_lower, u32 found_upper, 77 u32 event, u32 port, u32 node, 78 u32 scope, int must) 79 { 80 struct tipc_subscr *s = &sub->evt.s; 81 u32 filter = tipc_sub_read(s, filter); 82 struct tipc_name_seq seq; 83 84 seq.type = tipc_sub_read(s, seq.type); 85 seq.lower = tipc_sub_read(s, seq.lower); 86 seq.upper = tipc_sub_read(s, seq.upper); 87 88 if (!tipc_sub_check_overlap(&seq, found_lower, found_upper)) 89 return; 90 91 if (!must && !(filter & TIPC_SUB_PORTS)) 92 return; 93 if (filter & TIPC_SUB_CLUSTER_SCOPE && scope == TIPC_NODE_SCOPE) 94 return; 95 if (filter & TIPC_SUB_NODE_SCOPE && scope != TIPC_NODE_SCOPE) 96 return; 97 spin_lock(&sub->lock); 98 tipc_sub_send_event(sub, found_lower, found_upper, 99 event, port, node); 100 spin_unlock(&sub->lock); 101 } 102 103 static void tipc_sub_timeout(struct timer_list *t) 104 { 105 struct tipc_subscription *sub = from_timer(sub, t, timer); 106 struct tipc_subscr *s = &sub->evt.s; 107 108 spin_lock(&sub->lock); 109 tipc_sub_send_event(sub, s->seq.lower, s->seq.upper, 110 TIPC_SUBSCR_TIMEOUT, 0, 0); 111 sub->inactive = true; 112 spin_unlock(&sub->lock); 113 } 114 115 static void tipc_sub_kref_release(struct kref *kref) 116 { 117 kfree(container_of(kref, struct tipc_subscription, kref)); 118 } 119 120 void tipc_sub_put(struct tipc_subscription *subscription) 121 { 122 kref_put(&subscription->kref, tipc_sub_kref_release); 123 } 124 125 void tipc_sub_get(struct tipc_subscription *subscription) 126 { 127 kref_get(&subscription->kref); 128 } 129 130 struct tipc_subscription *tipc_sub_subscribe(struct net *net, 131 struct tipc_subscr *s, 132 int conid) 133 { 134 u32 filter = tipc_sub_read(s, filter); 135 struct tipc_subscription *sub; 136 u32 timeout; 137 138 if ((filter & TIPC_SUB_PORTS && filter & TIPC_SUB_SERVICE) || 139 (tipc_sub_read(s, seq.lower) > tipc_sub_read(s, seq.upper))) { 140 pr_warn("Subscription rejected, illegal request\n"); 141 return NULL; 142 } 143 sub = kmalloc(sizeof(*sub), GFP_ATOMIC); 144 if (!sub) { 145 pr_warn("Subscription rejected, no memory\n"); 146 return NULL; 147 } 148 INIT_LIST_HEAD(&sub->service_list); 149 INIT_LIST_HEAD(&sub->sub_list); 150 sub->net = net; 151 sub->conid = conid; 152 sub->inactive = false; 153 memcpy(&sub->evt.s, s, sizeof(*s)); 154 spin_lock_init(&sub->lock); 155 kref_init(&sub->kref); 156 if (!tipc_nametbl_subscribe(sub)) { 157 kfree(sub); 158 return NULL; 159 } 160 timer_setup(&sub->timer, tipc_sub_timeout, 0); 161 timeout = tipc_sub_read(&sub->evt.s, timeout); 162 if (timeout != TIPC_WAIT_FOREVER) 163 mod_timer(&sub->timer, jiffies + msecs_to_jiffies(timeout)); 164 return sub; 165 } 166 167 void tipc_sub_unsubscribe(struct tipc_subscription *sub) 168 { 169 tipc_nametbl_unsubscribe(sub); 170 if (sub->evt.s.timeout != TIPC_WAIT_FOREVER) 171 del_timer_sync(&sub->timer); 172 list_del(&sub->sub_list); 173 tipc_sub_put(sub); 174 } 175