blob: 2f6b3fcc79f81b9985ca5774a7fa3e070a105d11 [file] [log] [blame]
Andy Grover639b3212009-02-24 15:30:18 +00001/*
2 * Copyright (c) 2006 Oracle. All rights reserved.
3 *
4 * This software is available to you under a choice of one of two
5 * licenses. You may choose to be licensed under the terms of the GNU
6 * General Public License (GPL) Version 2, available from the file
7 * COPYING in the main directory of this source tree, or the
8 * OpenIB.org BSD license below:
9 *
10 * Redistribution and use in source and binary forms, with or
11 * without modification, are permitted provided that the following
12 * conditions are met:
13 *
14 * - Redistributions of source code must retain the above
15 * copyright notice, this list of conditions and the following
16 * disclaimer.
17 *
18 * - Redistributions in binary form must reproduce the above
19 * copyright notice, this list of conditions and the following
20 * disclaimer in the documentation and/or other materials
21 * provided with the distribution.
22 *
23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30 * SOFTWARE.
31 *
32 */
33#include <linux/kernel.h>
34#include <net/sock.h>
35#include <linux/in.h>
36#include <linux/if_arp.h>
Chris Mason38a4e5e2010-05-11 15:09:45 -070037#include <linux/jhash.h>
Andy Grover639b3212009-02-24 15:30:18 +000038#include "rds.h"
39
Chris Mason38a4e5e2010-05-11 15:09:45 -070040#define BIND_HASH_SIZE 1024
41static struct hlist_head bind_hash_table[BIND_HASH_SIZE];
42static DEFINE_SPINLOCK(rds_bind_lock);
Andy Grover639b3212009-02-24 15:30:18 +000043
Chris Mason38a4e5e2010-05-11 15:09:45 -070044static struct hlist_head *hash_to_bucket(__be32 addr, __be16 port)
Andy Grover639b3212009-02-24 15:30:18 +000045{
Chris Mason38a4e5e2010-05-11 15:09:45 -070046 return bind_hash_table + (jhash_2words((u32)addr, (u32)port, 0) &
47 (BIND_HASH_SIZE - 1));
48}
49
50static struct rds_sock *rds_bind_lookup(__be32 addr, __be16 port,
51 struct rds_sock *insert)
52{
Andy Grover639b3212009-02-24 15:30:18 +000053 struct rds_sock *rs;
Chris Mason38a4e5e2010-05-11 15:09:45 -070054 struct hlist_node *node;
55 struct hlist_head *head = hash_to_bucket(addr, port);
Andy Grover639b3212009-02-24 15:30:18 +000056 u64 cmp;
57 u64 needle = ((u64)be32_to_cpu(addr) << 32) | be16_to_cpu(port);
58
Chris Mason38a4e5e2010-05-11 15:09:45 -070059 rcu_read_lock();
60 hlist_for_each_entry_rcu(rs, node, head, rs_bound_node) {
Andy Grover639b3212009-02-24 15:30:18 +000061 cmp = ((u64)be32_to_cpu(rs->rs_bound_addr) << 32) |
62 be16_to_cpu(rs->rs_bound_port);
63
Chris Mason38a4e5e2010-05-11 15:09:45 -070064 if (cmp == needle) {
65 rcu_read_unlock();
Andy Grover639b3212009-02-24 15:30:18 +000066 return rs;
Chris Mason38a4e5e2010-05-11 15:09:45 -070067 }
Andy Grover639b3212009-02-24 15:30:18 +000068 }
Chris Mason38a4e5e2010-05-11 15:09:45 -070069 rcu_read_unlock();
Andy Grover639b3212009-02-24 15:30:18 +000070
71 if (insert) {
Chris Mason38a4e5e2010-05-11 15:09:45 -070072 /*
73 * make sure our addr and port are set before
74 * we are added to the list, other people
75 * in rcu will find us as soon as the
76 * hlist_add_head_rcu is done
77 */
78 insert->rs_bound_addr = addr;
79 insert->rs_bound_port = port;
80 rds_sock_addref(insert);
81
82 hlist_add_head_rcu(&insert->rs_bound_node, head);
Andy Grover639b3212009-02-24 15:30:18 +000083 }
84 return NULL;
85}
86
87/*
88 * Return the rds_sock bound at the given local address.
89 *
90 * The rx path can race with rds_release. We notice if rds_release() has
91 * marked this socket and don't return a rs ref to the rx path.
92 */
93struct rds_sock *rds_find_bound(__be32 addr, __be16 port)
94{
95 struct rds_sock *rs;
Andy Grover639b3212009-02-24 15:30:18 +000096
Chris Mason38a4e5e2010-05-11 15:09:45 -070097 rs = rds_bind_lookup(addr, port, NULL);
98
Andy Grover639b3212009-02-24 15:30:18 +000099 if (rs && !sock_flag(rds_rs_to_sk(rs), SOCK_DEAD))
100 rds_sock_addref(rs);
101 else
102 rs = NULL;
Andy Grover639b3212009-02-24 15:30:18 +0000103
104 rdsdebug("returning rs %p for %pI4:%u\n", rs, &addr,
105 ntohs(port));
106 return rs;
107}
108
109/* returns -ve errno or +ve port */
110static int rds_add_bound(struct rds_sock *rs, __be32 addr, __be16 *port)
111{
112 unsigned long flags;
113 int ret = -EADDRINUSE;
114 u16 rover, last;
115
116 if (*port != 0) {
117 rover = be16_to_cpu(*port);
118 last = rover;
119 } else {
120 rover = max_t(u16, net_random(), 2);
121 last = rover - 1;
122 }
123
Chris Mason38a4e5e2010-05-11 15:09:45 -0700124 spin_lock_irqsave(&rds_bind_lock, flags);
Andy Grover639b3212009-02-24 15:30:18 +0000125
126 do {
127 if (rover == 0)
128 rover++;
Chris Mason38a4e5e2010-05-11 15:09:45 -0700129 if (!rds_bind_lookup(addr, cpu_to_be16(rover), rs)) {
130 *port = rs->rs_bound_port;
Andy Grover639b3212009-02-24 15:30:18 +0000131 ret = 0;
Chris Mason38a4e5e2010-05-11 15:09:45 -0700132 rdsdebug("rs %p binding to %pI4:%d\n",
133 rs, &addr, (int)ntohs(*port));
Andy Grover639b3212009-02-24 15:30:18 +0000134 break;
135 }
136 } while (rover++ != last);
137
Chris Mason38a4e5e2010-05-11 15:09:45 -0700138 spin_unlock_irqrestore(&rds_bind_lock, flags);
Andy Grover639b3212009-02-24 15:30:18 +0000139
140 return ret;
141}
142
143void rds_remove_bound(struct rds_sock *rs)
144{
145 unsigned long flags;
146
Chris Mason38a4e5e2010-05-11 15:09:45 -0700147 spin_lock_irqsave(&rds_bind_lock, flags);
Andy Grover639b3212009-02-24 15:30:18 +0000148
149 if (rs->rs_bound_addr) {
150 rdsdebug("rs %p unbinding from %pI4:%d\n",
151 rs, &rs->rs_bound_addr,
152 ntohs(rs->rs_bound_port));
153
Chris Mason38a4e5e2010-05-11 15:09:45 -0700154 hlist_del_init_rcu(&rs->rs_bound_node);
Andy Grover639b3212009-02-24 15:30:18 +0000155 rds_sock_put(rs);
156 rs->rs_bound_addr = 0;
157 }
158
Chris Mason38a4e5e2010-05-11 15:09:45 -0700159 spin_unlock_irqrestore(&rds_bind_lock, flags);
Andy Grover639b3212009-02-24 15:30:18 +0000160}
161
162int rds_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
163{
164 struct sock *sk = sock->sk;
165 struct sockaddr_in *sin = (struct sockaddr_in *)uaddr;
166 struct rds_sock *rs = rds_sk_to_rs(sk);
167 struct rds_transport *trans;
168 int ret = 0;
169
170 lock_sock(sk);
171
172 if (addr_len != sizeof(struct sockaddr_in) ||
173 sin->sin_family != AF_INET ||
174 rs->rs_bound_addr ||
175 sin->sin_addr.s_addr == htonl(INADDR_ANY)) {
176 ret = -EINVAL;
177 goto out;
178 }
179
180 ret = rds_add_bound(rs, sin->sin_addr.s_addr, &sin->sin_port);
181 if (ret)
182 goto out;
183
184 trans = rds_trans_get_preferred(sin->sin_addr.s_addr);
Andy Grover8690bfa2010-01-12 11:56:44 -0800185 if (!trans) {
Andy Grover639b3212009-02-24 15:30:18 +0000186 ret = -EADDRNOTAVAIL;
187 rds_remove_bound(rs);
Andy Groverf2c44932009-08-21 12:28:35 +0000188 if (printk_ratelimit())
189 printk(KERN_INFO "RDS: rds_bind() could not find a transport, "
190 "load rds_tcp or rds_rdma?\n");
Andy Grover639b3212009-02-24 15:30:18 +0000191 goto out;
192 }
193
194 rs->rs_transport = trans;
195 ret = 0;
196
197out:
198 release_sock(sk);
Chris Mason38a4e5e2010-05-11 15:09:45 -0700199
200 /* we might have called rds_remove_bound on error */
201 if (ret)
202 synchronize_rcu();
Andy Grover639b3212009-02-24 15:30:18 +0000203 return ret;
204}