ia64/linux-2.6.18-xen.hg

view net/ipv6/inet6_hashtables.c @ 673:3161879fdf22

[IA64] xencomm: support XENMEM_add_to_physmap and XENMEM_remove_from_phsymap

support XENMEM_add_to_physmap and XENMEM_remove_from_phsymap.

Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
author Isaku Yamahata <yamahata@valinux.co.jp>
date Tue Sep 16 21:26:15 2008 +0900 (2008-09-16)
parents 831230e53067
children
line source
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.
5 *
6 * Generic INET6 transport hashtables
7 *
8 * Authors: Lotsa people, from code originally in tcp, generalised here
9 * by Arnaldo Carvalho de Melo <acme@mandriva.com>
10 *
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.
15 */
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)
27 {
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 hash &= (hashinfo->ehash_size - 1);
41 list = &hashinfo->ehash[hash].chain;
42 lock = &hashinfo->ehash[hash].lock;
43 write_lock(lock);
44 }
46 __sk_add_node(sk, list);
47 sock_prot_inc_use(sk->sk_prot);
48 write_unlock(lock);
49 }
50 EXPORT_SYMBOL(__inet6_hash);
52 /*
53 * Sockets in TCP_CLOSE state are _always_ taken out of the hash, so
54 * we need not check it for TCP lookups anymore, thanks Alexey. -DaveM
55 *
56 * The sockhash lock must be held as a reader here.
57 */
58 struct sock *__inet6_lookup_established(struct inet_hashinfo *hashinfo,
59 const struct in6_addr *saddr,
60 const u16 sport,
61 const struct in6_addr *daddr,
62 const u16 hnum,
63 const int dif)
64 {
65 struct sock *sk;
66 const struct hlist_node *node;
67 const __u32 ports = INET_COMBINED_PORTS(sport, hnum);
68 /* Optimize here for direct hit, only listening connections can
69 * have wildcards anyways.
70 */
71 unsigned int hash = inet6_ehashfn(daddr, hnum, saddr, sport);
72 struct inet_ehash_bucket *head = inet_ehash_bucket(hashinfo, hash);
74 prefetch(head->chain.first);
75 read_lock(&head->lock);
76 sk_for_each(sk, node, &head->chain) {
77 /* For IPV6 do the cheaper port and family tests first. */
78 if (INET6_MATCH(sk, hash, saddr, daddr, ports, dif))
79 goto hit; /* You sunk my battleship! */
80 }
81 /* Must check for a TIME_WAIT'er before going to listener hash. */
82 sk_for_each(sk, node, &(head + hashinfo->ehash_size)->chain) {
83 const struct inet_timewait_sock *tw = inet_twsk(sk);
85 if(*((__u32 *)&(tw->tw_dport)) == ports &&
86 sk->sk_family == PF_INET6) {
87 const struct inet6_timewait_sock *tw6 = inet6_twsk(sk);
89 if (ipv6_addr_equal(&tw6->tw_v6_daddr, saddr) &&
90 ipv6_addr_equal(&tw6->tw_v6_rcv_saddr, daddr) &&
91 (!sk->sk_bound_dev_if || sk->sk_bound_dev_if == dif))
92 goto hit;
93 }
94 }
95 read_unlock(&head->lock);
96 return NULL;
98 hit:
99 sock_hold(sk);
100 read_unlock(&head->lock);
101 return sk;
102 }
103 EXPORT_SYMBOL(__inet6_lookup_established);
105 struct sock *inet6_lookup_listener(struct inet_hashinfo *hashinfo,
106 const struct in6_addr *daddr,
107 const unsigned short hnum, const int dif)
108 {
109 struct sock *sk;
110 const struct hlist_node *node;
111 struct sock *result = NULL;
112 int score, hiscore = 0;
114 read_lock(&hashinfo->lhash_lock);
115 sk_for_each(sk, node, &hashinfo->listening_hash[inet_lhashfn(hnum)]) {
116 if (inet_sk(sk)->num == hnum && sk->sk_family == PF_INET6) {
117 const struct ipv6_pinfo *np = inet6_sk(sk);
119 score = 1;
120 if (!ipv6_addr_any(&np->rcv_saddr)) {
121 if (!ipv6_addr_equal(&np->rcv_saddr, daddr))
122 continue;
123 score++;
124 }
125 if (sk->sk_bound_dev_if) {
126 if (sk->sk_bound_dev_if != dif)
127 continue;
128 score++;
129 }
130 if (score == 3) {
131 result = sk;
132 break;
133 }
134 if (score > hiscore) {
135 hiscore = score;
136 result = sk;
137 }
138 }
139 }
140 if (result)
141 sock_hold(result);
142 read_unlock(&hashinfo->lhash_lock);
143 return result;
144 }
146 EXPORT_SYMBOL_GPL(inet6_lookup_listener);
148 struct sock *inet6_lookup(struct inet_hashinfo *hashinfo,
149 const struct in6_addr *saddr, const u16 sport,
150 const struct in6_addr *daddr, const u16 dport,
151 const int dif)
152 {
153 struct sock *sk;
155 local_bh_disable();
156 sk = __inet6_lookup(hashinfo, saddr, sport, daddr, ntohs(dport), dif);
157 local_bh_enable();
159 return sk;
160 }
162 EXPORT_SYMBOL_GPL(inet6_lookup);
164 static int __inet6_check_established(struct inet_timewait_death_row *death_row,
165 struct sock *sk, const __u16 lport,
166 struct inet_timewait_sock **twp)
167 {
168 struct inet_hashinfo *hinfo = death_row->hashinfo;
169 struct inet_sock *inet = inet_sk(sk);
170 const struct ipv6_pinfo *np = inet6_sk(sk);
171 const struct in6_addr *daddr = &np->rcv_saddr;
172 const struct in6_addr *saddr = &np->daddr;
173 const int dif = sk->sk_bound_dev_if;
174 const u32 ports = INET_COMBINED_PORTS(inet->dport, lport);
175 const unsigned int hash = inet6_ehashfn(daddr, inet->num, saddr,
176 inet->dport);
177 struct inet_ehash_bucket *head = inet_ehash_bucket(hinfo, hash);
178 struct sock *sk2;
179 const struct hlist_node *node;
180 struct inet_timewait_sock *tw;
182 prefetch(head->chain.first);
183 write_lock(&head->lock);
185 /* Check TIME-WAIT sockets first. */
186 sk_for_each(sk2, node, &(head + hinfo->ehash_size)->chain) {
187 const struct inet6_timewait_sock *tw6 = inet6_twsk(sk2);
189 tw = inet_twsk(sk2);
191 if(*((__u32 *)&(tw->tw_dport)) == ports &&
192 sk2->sk_family == PF_INET6 &&
193 ipv6_addr_equal(&tw6->tw_v6_daddr, saddr) &&
194 ipv6_addr_equal(&tw6->tw_v6_rcv_saddr, daddr) &&
195 sk2->sk_bound_dev_if == sk->sk_bound_dev_if) {
196 if (twsk_unique(sk, sk2, twp))
197 goto unique;
198 else
199 goto not_unique;
200 }
201 }
202 tw = NULL;
204 /* And established part... */
205 sk_for_each(sk2, node, &head->chain) {
206 if (INET6_MATCH(sk2, hash, saddr, daddr, ports, dif))
207 goto not_unique;
208 }
210 unique:
211 /* Must record num and sport now. Otherwise we will see
212 * in hash table socket with a funny identity. */
213 inet->num = lport;
214 inet->sport = htons(lport);
215 BUG_TRAP(sk_unhashed(sk));
216 __sk_add_node(sk, &head->chain);
217 sk->sk_hash = hash;
218 sock_prot_inc_use(sk->sk_prot);
219 write_unlock(&head->lock);
221 if (twp != NULL) {
222 *twp = tw;
223 NET_INC_STATS_BH(LINUX_MIB_TIMEWAITRECYCLED);
224 } else if (tw != NULL) {
225 /* Silly. Should hash-dance instead... */
226 inet_twsk_deschedule(tw, death_row);
227 NET_INC_STATS_BH(LINUX_MIB_TIMEWAITRECYCLED);
229 inet_twsk_put(tw);
230 }
231 return 0;
233 not_unique:
234 write_unlock(&head->lock);
235 return -EADDRNOTAVAIL;
236 }
238 static inline u32 inet6_sk_port_offset(const struct sock *sk)
239 {
240 const struct inet_sock *inet = inet_sk(sk);
241 const struct ipv6_pinfo *np = inet6_sk(sk);
242 return secure_ipv6_port_ephemeral(np->rcv_saddr.s6_addr32,
243 np->daddr.s6_addr32,
244 inet->dport);
245 }
247 int inet6_hash_connect(struct inet_timewait_death_row *death_row,
248 struct sock *sk)
249 {
250 struct inet_hashinfo *hinfo = death_row->hashinfo;
251 const unsigned short snum = inet_sk(sk)->num;
252 struct inet_bind_hashbucket *head;
253 struct inet_bind_bucket *tb;
254 int ret;
256 if (snum == 0) {
257 const int low = sysctl_local_port_range[0];
258 const int high = sysctl_local_port_range[1];
259 const int range = high - low;
260 int i, port;
261 static u32 hint;
262 const u32 offset = hint + inet6_sk_port_offset(sk);
263 struct hlist_node *node;
264 struct inet_timewait_sock *tw = NULL;
266 local_bh_disable();
267 for (i = 1; i <= range; i++) {
268 port = low + (i + offset) % range;
269 head = &hinfo->bhash[inet_bhashfn(port, hinfo->bhash_size)];
270 spin_lock(&head->lock);
272 /* Does not bother with rcv_saddr checks,
273 * because the established check is already
274 * unique enough.
275 */
276 inet_bind_bucket_for_each(tb, node, &head->chain) {
277 if (tb->port == port) {
278 BUG_TRAP(!hlist_empty(&tb->owners));
279 if (tb->fastreuse >= 0)
280 goto next_port;
281 if (!__inet6_check_established(death_row,
282 sk, port,
283 &tw))
284 goto ok;
285 goto next_port;
286 }
287 }
289 tb = inet_bind_bucket_create(hinfo->bind_bucket_cachep,
290 head, port);
291 if (!tb) {
292 spin_unlock(&head->lock);
293 break;
294 }
295 tb->fastreuse = -1;
296 goto ok;
298 next_port:
299 spin_unlock(&head->lock);
300 }
301 local_bh_enable();
303 return -EADDRNOTAVAIL;
305 ok:
306 hint += i;
308 /* Head lock still held and bh's disabled */
309 inet_bind_hash(sk, tb, port);
310 if (sk_unhashed(sk)) {
311 inet_sk(sk)->sport = htons(port);
312 __inet6_hash(hinfo, sk);
313 }
314 spin_unlock(&head->lock);
316 if (tw) {
317 inet_twsk_deschedule(tw, death_row);
318 inet_twsk_put(tw);
319 }
321 ret = 0;
322 goto out;
323 }
325 head = &hinfo->bhash[inet_bhashfn(snum, hinfo->bhash_size)];
326 tb = inet_csk(sk)->icsk_bind_hash;
327 spin_lock_bh(&head->lock);
329 if (sk_head(&tb->owners) == sk && sk->sk_bind_node.next == NULL) {
330 __inet6_hash(hinfo, sk);
331 spin_unlock_bh(&head->lock);
332 return 0;
333 } else {
334 spin_unlock(&head->lock);
335 /* No definite answer... Walk to established hash table */
336 ret = __inet6_check_established(death_row, sk, snum, NULL);
337 out:
338 local_bh_enable();
339 return ret;
340 }
341 }
343 EXPORT_SYMBOL_GPL(inet6_hash_connect);