1 /* AF_RXRPC local endpoint management
3 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
12 #include <linux/module.h>
13 #include <linux/net.h>
14 #include <linux/skbuff.h>
16 #include <net/af_rxrpc.h>
17 #include "ar-internal.h"
19 static LIST_HEAD(rxrpc_locals);
20 DEFINE_RWLOCK(rxrpc_local_lock);
21 static DECLARE_RWSEM(rxrpc_local_sem);
22 static DECLARE_WAIT_QUEUE_HEAD(rxrpc_local_wq);
24 static void rxrpc_destroy_local(struct work_struct *work);
27 * allocate a new local
30 struct rxrpc_local *rxrpc_alloc_local(struct sockaddr_rxrpc *srx)
32 struct rxrpc_local *local;
34 local = kzalloc(sizeof(struct rxrpc_local), GFP_KERNEL);
36 INIT_WORK(&local->destroyer, &rxrpc_destroy_local);
37 INIT_WORK(&local->acceptor, &rxrpc_accept_incoming_calls);
38 INIT_WORK(&local->rejecter, &rxrpc_reject_packets);
39 INIT_LIST_HEAD(&local->services);
40 INIT_LIST_HEAD(&local->link);
41 init_rwsem(&local->defrag_sem);
42 skb_queue_head_init(&local->accept_queue);
43 skb_queue_head_init(&local->reject_queue);
44 spin_lock_init(&local->lock);
45 rwlock_init(&local->services_lock);
46 atomic_set(&local->usage, 1);
47 local->debug_id = atomic_inc_return(&rxrpc_debug_id);
48 memcpy(&local->srx, srx, sizeof(*srx));
51 _leave(" = %p", local);
56 * create the local socket
57 * - must be called with rxrpc_local_sem writelocked
59 static int rxrpc_create_local(struct rxrpc_local *local)
64 _enter("%p{%d}", local, local->srx.transport_type);
66 /* create a socket to represent the local endpoint */
67 ret = sock_create_kern(PF_INET, local->srx.transport_type, IPPROTO_UDP,
70 _leave(" = %d [socket]", ret);
74 /* if a local address was supplied then bind it */
75 if (local->srx.transport_len > sizeof(sa_family_t)) {
77 ret = kernel_bind(local->socket,
78 (struct sockaddr *) &local->srx.transport,
79 local->srx.transport_len);
81 _debug("bind failed");
86 /* we want to receive ICMP errors */
88 ret = kernel_setsockopt(local->socket, SOL_IP, IP_RECVERR,
89 (char *) &opt, sizeof(opt));
91 _debug("setsockopt failed");
95 /* we want to set the don't fragment bit */
97 ret = kernel_setsockopt(local->socket, SOL_IP, IP_MTU_DISCOVER,
98 (char *) &opt, sizeof(opt));
100 _debug("setsockopt failed");
104 write_lock_bh(&rxrpc_local_lock);
105 list_add(&local->link, &rxrpc_locals);
106 write_unlock_bh(&rxrpc_local_lock);
108 /* set the socket up */
109 sock = local->socket->sk;
110 sock->sk_user_data = local;
111 sock->sk_data_ready = rxrpc_data_ready;
112 sock->sk_error_report = rxrpc_UDP_error_report;
117 kernel_sock_shutdown(local->socket, SHUT_RDWR);
118 local->socket->sk->sk_user_data = NULL;
119 sock_release(local->socket);
120 local->socket = NULL;
122 _leave(" = %d", ret);
127 * create a new local endpoint using the specified UDP address
129 struct rxrpc_local *rxrpc_lookup_local(struct sockaddr_rxrpc *srx)
131 struct rxrpc_local *local;
134 _enter("{%d,%u,%pI4+%hu}",
136 srx->transport.family,
137 &srx->transport.sin.sin_addr,
138 ntohs(srx->transport.sin.sin_port));
140 down_write(&rxrpc_local_sem);
142 /* see if we have a suitable local local endpoint already */
143 read_lock_bh(&rxrpc_local_lock);
145 list_for_each_entry(local, &rxrpc_locals, link) {
146 _debug("CMP {%d,%u,%pI4+%hu}",
147 local->srx.transport_type,
148 local->srx.transport.family,
149 &local->srx.transport.sin.sin_addr,
150 ntohs(local->srx.transport.sin.sin_port));
152 if (local->srx.transport_type != srx->transport_type ||
153 local->srx.transport.family != srx->transport.family)
156 switch (srx->transport.family) {
158 if (local->srx.transport.sin.sin_port !=
159 srx->transport.sin.sin_port)
161 if (memcmp(&local->srx.transport.sin.sin_addr,
162 &srx->transport.sin.sin_addr,
163 sizeof(struct in_addr)) != 0)
172 read_unlock_bh(&rxrpc_local_lock);
174 /* we didn't find one, so we need to create one */
175 local = rxrpc_alloc_local(srx);
177 up_write(&rxrpc_local_sem);
178 return ERR_PTR(-ENOMEM);
181 ret = rxrpc_create_local(local);
183 up_write(&rxrpc_local_sem);
185 _leave(" = %d", ret);
189 up_write(&rxrpc_local_sem);
191 _net("LOCAL new %d {%d,%u,%pI4+%hu}",
193 local->srx.transport_type,
194 local->srx.transport.family,
195 &local->srx.transport.sin.sin_addr,
196 ntohs(local->srx.transport.sin.sin_port));
198 _leave(" = %p [new]", local);
202 rxrpc_get_local(local);
203 read_unlock_bh(&rxrpc_local_lock);
204 up_write(&rxrpc_local_sem);
206 _net("LOCAL old %d {%d,%u,%pI4+%hu}",
208 local->srx.transport_type,
209 local->srx.transport.family,
210 &local->srx.transport.sin.sin_addr,
211 ntohs(local->srx.transport.sin.sin_port));
213 _leave(" = %p [reuse]", local);
218 * release a local endpoint
220 void rxrpc_put_local(struct rxrpc_local *local)
222 _enter("%p{u=%d}", local, atomic_read(&local->usage));
224 ASSERTCMP(atomic_read(&local->usage), >, 0);
226 /* to prevent a race, the decrement and the dequeue must be effectively
228 write_lock_bh(&rxrpc_local_lock);
229 if (unlikely(atomic_dec_and_test(&local->usage))) {
230 _debug("destroy local");
231 rxrpc_queue_work(&local->destroyer);
233 write_unlock_bh(&rxrpc_local_lock);
238 * destroy a local endpoint
240 static void rxrpc_destroy_local(struct work_struct *work)
242 struct rxrpc_local *local =
243 container_of(work, struct rxrpc_local, destroyer);
245 _enter("%p{%d}", local, atomic_read(&local->usage));
247 down_write(&rxrpc_local_sem);
249 write_lock_bh(&rxrpc_local_lock);
250 if (atomic_read(&local->usage) > 0) {
251 write_unlock_bh(&rxrpc_local_lock);
252 up_read(&rxrpc_local_sem);
253 _leave(" [resurrected]");
257 list_del(&local->link);
258 local->socket->sk->sk_user_data = NULL;
259 write_unlock_bh(&rxrpc_local_lock);
261 downgrade_write(&rxrpc_local_sem);
263 ASSERT(list_empty(&local->services));
264 ASSERT(!work_pending(&local->acceptor));
265 ASSERT(!work_pending(&local->rejecter));
267 /* finish cleaning up the local descriptor */
268 rxrpc_purge_queue(&local->accept_queue);
269 rxrpc_purge_queue(&local->reject_queue);
270 kernel_sock_shutdown(local->socket, SHUT_RDWR);
271 sock_release(local->socket);
273 up_read(&rxrpc_local_sem);
275 _net("DESTROY LOCAL %d", local->debug_id);
278 if (list_empty(&rxrpc_locals))
279 wake_up_all(&rxrpc_local_wq);
285 * preemptively destroy all local local endpoint rather than waiting for
286 * them to be destroyed
288 void __exit rxrpc_destroy_all_locals(void)
290 DECLARE_WAITQUEUE(myself,current);
294 /* we simply have to wait for them to go away */
295 if (!list_empty(&rxrpc_locals)) {
296 set_current_state(TASK_UNINTERRUPTIBLE);
297 add_wait_queue(&rxrpc_local_wq, &myself);
299 while (!list_empty(&rxrpc_locals)) {
301 set_current_state(TASK_UNINTERRUPTIBLE);
304 remove_wait_queue(&rxrpc_local_wq, &myself);
305 set_current_state(TASK_RUNNING);