x86: support gbpages in pagetable dump
[wrt350n-kernel.git] / net / ipv6 / inet6_hashtables.c
blobd325a995890911ec0f4418c2f00f0034231111e0
1 /*
2 * INET An implementation of the TCP/IP protocol suite for the LINUX
3 * operating system. INET is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
6 * Generic INET6 transport hashtables
8 * Authors: Lotsa people, from code originally in tcp, generalised here
9 * by Arnaldo Carvalho de Melo <acme@mandriva.com>
11 * This program is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU General Public License
13 * as published by the Free Software Foundation; either version
14 * 2 of the License, or (at your option) any later version.
17 #include <linux/module.h>
18 #include <linux/random.h>
20 #include <net/inet_connection_sock.h>
21 #include <net/inet_hashtables.h>
22 #include <net/inet6_hashtables.h>
23 #include <net/ip.h>
25 void __inet6_hash(struct inet_hashinfo *hashinfo,
26 struct sock *sk)
28 struct hlist_head *list;
29 rwlock_t *lock;
31 BUG_TRAP(sk_unhashed(sk));
33 if (sk->sk_state == TCP_LISTEN) {
34 list = &hashinfo->listening_hash[inet_sk_listen_hashfn(sk)];
35 lock = &hashinfo->lhash_lock;
36 inet_listen_wlock(hashinfo);
37 } else {
38 unsigned int hash;
39 sk->sk_hash = hash = inet6_sk_ehashfn(sk);
40 list = &inet_ehash_bucket(hashinfo, hash)->chain;
41 lock = inet_ehash_lockp(hashinfo, hash);
42 write_lock(lock);
45 __sk_add_node(sk, list);
46 sock_prot_inuse_add(sk->sk_prot, 1);
47 write_unlock(lock);
49 EXPORT_SYMBOL(__inet6_hash);
52 * Sockets in TCP_CLOSE state are _always_ taken out of the hash, so
53 * we need not check it for TCP lookups anymore, thanks Alexey. -DaveM
55 * The sockhash lock must be held as a reader here.
57 struct sock *__inet6_lookup_established(struct net *net,
58 struct inet_hashinfo *hashinfo,
59 const struct in6_addr *saddr,
60 const __be16 sport,
61 const struct in6_addr *daddr,
62 const u16 hnum,
63 const int dif)
65 struct sock *sk;
66 const struct hlist_node *node;
67 const __portpair ports = INET_COMBINED_PORTS(sport, hnum);
68 /* Optimize here for direct hit, only listening connections can
69 * have wildcards anyways.
71 unsigned int hash = inet6_ehashfn(daddr, hnum, saddr, sport);
72 struct inet_ehash_bucket *head = inet_ehash_bucket(hashinfo, hash);
73 rwlock_t *lock = inet_ehash_lockp(hashinfo, hash);
75 prefetch(head->chain.first);
76 read_lock(lock);
77 sk_for_each(sk, node, &head->chain) {
78 /* For IPV6 do the cheaper port and family tests first. */
79 if (INET6_MATCH(sk, net, hash, saddr, daddr, ports, dif))
80 goto hit; /* You sunk my battleship! */
82 /* Must check for a TIME_WAIT'er before going to listener hash. */
83 sk_for_each(sk, node, &head->twchain) {
84 if (INET6_TW_MATCH(sk, net, hash, saddr, daddr, ports, dif))
85 goto hit;
87 read_unlock(lock);
88 return NULL;
90 hit:
91 sock_hold(sk);
92 read_unlock(lock);
93 return sk;
95 EXPORT_SYMBOL(__inet6_lookup_established);
97 struct sock *inet6_lookup_listener(struct net *net,
98 struct inet_hashinfo *hashinfo, const struct in6_addr *daddr,
99 const unsigned short hnum, const int dif)
101 struct sock *sk;
102 const struct hlist_node *node;
103 struct sock *result = NULL;
104 int score, hiscore = 0;
106 read_lock(&hashinfo->lhash_lock);
107 sk_for_each(sk, node, &hashinfo->listening_hash[inet_lhashfn(hnum)]) {
108 if (sk->sk_net == net && inet_sk(sk)->num == hnum &&
109 sk->sk_family == PF_INET6) {
110 const struct ipv6_pinfo *np = inet6_sk(sk);
112 score = 1;
113 if (!ipv6_addr_any(&np->rcv_saddr)) {
114 if (!ipv6_addr_equal(&np->rcv_saddr, daddr))
115 continue;
116 score++;
118 if (sk->sk_bound_dev_if) {
119 if (sk->sk_bound_dev_if != dif)
120 continue;
121 score++;
123 if (score == 3) {
124 result = sk;
125 break;
127 if (score > hiscore) {
128 hiscore = score;
129 result = sk;
133 if (result)
134 sock_hold(result);
135 read_unlock(&hashinfo->lhash_lock);
136 return result;
139 EXPORT_SYMBOL_GPL(inet6_lookup_listener);
141 struct sock *inet6_lookup(struct net *net, struct inet_hashinfo *hashinfo,
142 const struct in6_addr *saddr, const __be16 sport,
143 const struct in6_addr *daddr, const __be16 dport,
144 const int dif)
146 struct sock *sk;
148 local_bh_disable();
149 sk = __inet6_lookup(net, hashinfo, saddr, sport, daddr, ntohs(dport), dif);
150 local_bh_enable();
152 return sk;
155 EXPORT_SYMBOL_GPL(inet6_lookup);
157 static int __inet6_check_established(struct inet_timewait_death_row *death_row,
158 struct sock *sk, const __u16 lport,
159 struct inet_timewait_sock **twp)
161 struct inet_hashinfo *hinfo = death_row->hashinfo;
162 struct inet_sock *inet = inet_sk(sk);
163 const struct ipv6_pinfo *np = inet6_sk(sk);
164 const struct in6_addr *daddr = &np->rcv_saddr;
165 const struct in6_addr *saddr = &np->daddr;
166 const int dif = sk->sk_bound_dev_if;
167 const __portpair ports = INET_COMBINED_PORTS(inet->dport, lport);
168 const unsigned int hash = inet6_ehashfn(daddr, lport, saddr,
169 inet->dport);
170 struct inet_ehash_bucket *head = inet_ehash_bucket(hinfo, hash);
171 rwlock_t *lock = inet_ehash_lockp(hinfo, hash);
172 struct sock *sk2;
173 const struct hlist_node *node;
174 struct inet_timewait_sock *tw;
175 struct net *net = sk->sk_net;
177 prefetch(head->chain.first);
178 write_lock(lock);
180 /* Check TIME-WAIT sockets first. */
181 sk_for_each(sk2, node, &head->twchain) {
182 tw = inet_twsk(sk2);
184 if (INET6_TW_MATCH(sk2, net, hash, saddr, daddr, ports, dif)) {
185 if (twsk_unique(sk, sk2, twp))
186 goto unique;
187 else
188 goto not_unique;
191 tw = NULL;
193 /* And established part... */
194 sk_for_each(sk2, node, &head->chain) {
195 if (INET6_MATCH(sk2, net, hash, saddr, daddr, ports, dif))
196 goto not_unique;
199 unique:
200 /* Must record num and sport now. Otherwise we will see
201 * in hash table socket with a funny identity. */
202 inet->num = lport;
203 inet->sport = htons(lport);
204 BUG_TRAP(sk_unhashed(sk));
205 __sk_add_node(sk, &head->chain);
206 sk->sk_hash = hash;
207 sock_prot_inuse_add(sk->sk_prot, 1);
208 write_unlock(lock);
210 if (twp != NULL) {
211 *twp = tw;
212 NET_INC_STATS_BH(LINUX_MIB_TIMEWAITRECYCLED);
213 } else if (tw != NULL) {
214 /* Silly. Should hash-dance instead... */
215 inet_twsk_deschedule(tw, death_row);
216 NET_INC_STATS_BH(LINUX_MIB_TIMEWAITRECYCLED);
218 inet_twsk_put(tw);
220 return 0;
222 not_unique:
223 write_unlock(lock);
224 return -EADDRNOTAVAIL;
227 static inline u32 inet6_sk_port_offset(const struct sock *sk)
229 const struct inet_sock *inet = inet_sk(sk);
230 const struct ipv6_pinfo *np = inet6_sk(sk);
231 return secure_ipv6_port_ephemeral(np->rcv_saddr.s6_addr32,
232 np->daddr.s6_addr32,
233 inet->dport);
236 int inet6_hash_connect(struct inet_timewait_death_row *death_row,
237 struct sock *sk)
239 return __inet_hash_connect(death_row, sk,
240 __inet6_check_established, __inet6_hash);
243 EXPORT_SYMBOL_GPL(inet6_hash_connect);