Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6
[linux-2.6.git] / include / net / inet_connection_sock.h
1 /*
2  * NET          Generic infrastructure for INET connection oriented protocols.
3  *
4  *              Definitions for inet_connection_sock 
5  *
6  * Authors:     Many people, see the TCP sources
7  *
8  *              From code originally in TCP
9  *
10  *              This program is free software; you can redistribute it and/or
11  *              modify it under the terms of the GNU General Public License
12  *              as published by the Free Software Foundation; either version
13  *              2 of the License, or (at your option) any later version.
14  */
15 #ifndef _INET_CONNECTION_SOCK_H
16 #define _INET_CONNECTION_SOCK_H
17
18 #include <linux/compiler.h>
19 #include <linux/string.h>
20 #include <linux/timer.h>
21 #include <linux/poll.h>
22
23 #include <net/inet_sock.h>
24 #include <net/request_sock.h>
25
26 #define INET_CSK_DEBUG 1
27
28 /* Cancel timers, when they are not required. */
29 #undef INET_CSK_CLEAR_TIMERS
30
31 struct inet_bind_bucket;
32 struct tcp_congestion_ops;
33
34 /*
35  * Pointers to address related TCP functions
36  * (i.e. things that depend on the address family)
37  */
38 struct inet_connection_sock_af_ops {
39         int         (*queue_xmit)(struct sk_buff *skb, int ipfragok);
40         void        (*send_check)(struct sock *sk, int len,
41                                   struct sk_buff *skb);
42         int         (*rebuild_header)(struct sock *sk);
43         int         (*conn_request)(struct sock *sk, struct sk_buff *skb);
44         struct sock *(*syn_recv_sock)(struct sock *sk, struct sk_buff *skb,
45                                       struct request_sock *req,
46                                       struct dst_entry *dst);
47         int         (*remember_stamp)(struct sock *sk);
48         u16         net_header_len;
49         u16         sockaddr_len;
50         int         (*setsockopt)(struct sock *sk, int level, int optname, 
51                                   char __user *optval, unsigned int optlen);
52         int         (*getsockopt)(struct sock *sk, int level, int optname, 
53                                   char __user *optval, int __user *optlen);
54 #ifdef CONFIG_COMPAT
55         int         (*compat_setsockopt)(struct sock *sk,
56                                 int level, int optname,
57                                 char __user *optval, unsigned int optlen);
58         int         (*compat_getsockopt)(struct sock *sk,
59                                 int level, int optname,
60                                 char __user *optval, int __user *optlen);
61 #endif
62         void        (*addr2sockaddr)(struct sock *sk, struct sockaddr *);
63         int         (*bind_conflict)(const struct sock *sk,
64                                      const struct inet_bind_bucket *tb);
65 };
66
67 /** inet_connection_sock - INET connection oriented sock
68  *
69  * @icsk_accept_queue:     FIFO of established children 
70  * @icsk_bind_hash:        Bind node
71  * @icsk_timeout:          Timeout
72  * @icsk_retransmit_timer: Resend (no ack)
73  * @icsk_rto:              Retransmit timeout
74  * @icsk_pmtu_cookie       Last pmtu seen by socket
75  * @icsk_ca_ops            Pluggable congestion control hook
76  * @icsk_af_ops            Operations which are AF_INET{4,6} specific
77  * @icsk_ca_state:         Congestion control state
78  * @icsk_retransmits:      Number of unrecovered [RTO] timeouts
79  * @icsk_pending:          Scheduled timer event
80  * @icsk_backoff:          Backoff
81  * @icsk_syn_retries:      Number of allowed SYN (or equivalent) retries
82  * @icsk_probes_out:       unanswered 0 window probes
83  * @icsk_ext_hdr_len:      Network protocol overhead (IP/IPv6 options)
84  * @icsk_ack:              Delayed ACK control data
85  * @icsk_mtup;             MTU probing control data
86  */
87 struct inet_connection_sock {
88         /* inet_sock has to be the first member! */
89         struct inet_sock          icsk_inet;
90         struct request_sock_queue icsk_accept_queue;
91         struct inet_bind_bucket   *icsk_bind_hash;
92         unsigned long             icsk_timeout;
93         struct timer_list         icsk_retransmit_timer;
94         struct timer_list         icsk_delack_timer;
95         __u32                     icsk_rto;
96         __u32                     icsk_pmtu_cookie;
97         const struct tcp_congestion_ops *icsk_ca_ops;
98         const struct inet_connection_sock_af_ops *icsk_af_ops;
99         unsigned int              (*icsk_sync_mss)(struct sock *sk, u32 pmtu);
100         __u8                      icsk_ca_state;
101         __u8                      icsk_retransmits;
102         __u8                      icsk_pending;
103         __u8                      icsk_backoff;
104         __u8                      icsk_syn_retries;
105         __u8                      icsk_probes_out;
106         __u16                     icsk_ext_hdr_len;
107         struct {
108                 __u8              pending;       /* ACK is pending                         */
109                 __u8              quick;         /* Scheduled number of quick acks         */
110                 __u8              pingpong;      /* The session is interactive             */
111                 __u8              blocked;       /* Delayed ACK was blocked by socket lock */
112                 __u32             ato;           /* Predicted tick of soft clock           */
113                 unsigned long     timeout;       /* Currently scheduled timeout            */
114                 __u32             lrcvtime;      /* timestamp of last received data packet */
115                 __u16             last_seg_size; /* Size of last incoming segment          */
116                 __u16             rcv_mss;       /* MSS used for delayed ACK decisions     */ 
117         } icsk_ack;
118         struct {
119                 int               enabled;
120
121                 /* Range of MTUs to search */
122                 int               search_high;
123                 int               search_low;
124
125                 /* Information on the current probe. */
126                 int               probe_size;
127         } icsk_mtup;
128         u32                       icsk_ca_priv[16];
129 #define ICSK_CA_PRIV_SIZE       (16 * sizeof(u32))
130 };
131
132 #define ICSK_TIME_RETRANS       1       /* Retransmit timer */
133 #define ICSK_TIME_DACK          2       /* Delayed ack timer */
134 #define ICSK_TIME_PROBE0        3       /* Zero window probe timer */
135 #define ICSK_TIME_KEEPOPEN      4       /* Keepalive timer */
136
137 static inline struct inet_connection_sock *inet_csk(const struct sock *sk)
138 {
139         return (struct inet_connection_sock *)sk;
140 }
141
142 static inline void *inet_csk_ca(const struct sock *sk)
143 {
144         return (void *)inet_csk(sk)->icsk_ca_priv;
145 }
146
147 extern struct sock *inet_csk_clone(struct sock *sk,
148                                    const struct request_sock *req,
149                                    const gfp_t priority);
150
151 enum inet_csk_ack_state_t {
152         ICSK_ACK_SCHED  = 1,
153         ICSK_ACK_TIMER  = 2,
154         ICSK_ACK_PUSHED = 4,
155         ICSK_ACK_PUSHED2 = 8
156 };
157
158 extern void inet_csk_init_xmit_timers(struct sock *sk,
159                                       void (*retransmit_handler)(unsigned long),
160                                       void (*delack_handler)(unsigned long),
161                                       void (*keepalive_handler)(unsigned long));
162 extern void inet_csk_clear_xmit_timers(struct sock *sk);
163
164 static inline void inet_csk_schedule_ack(struct sock *sk)
165 {
166         inet_csk(sk)->icsk_ack.pending |= ICSK_ACK_SCHED;
167 }
168
169 static inline int inet_csk_ack_scheduled(const struct sock *sk)
170 {
171         return inet_csk(sk)->icsk_ack.pending & ICSK_ACK_SCHED;
172 }
173
174 static inline void inet_csk_delack_init(struct sock *sk)
175 {
176         memset(&inet_csk(sk)->icsk_ack, 0, sizeof(inet_csk(sk)->icsk_ack));
177 }
178
179 extern void inet_csk_delete_keepalive_timer(struct sock *sk);
180 extern void inet_csk_reset_keepalive_timer(struct sock *sk, unsigned long timeout);
181
182 #ifdef INET_CSK_DEBUG
183 extern const char inet_csk_timer_bug_msg[];
184 #endif
185
186 static inline void inet_csk_clear_xmit_timer(struct sock *sk, const int what)
187 {
188         struct inet_connection_sock *icsk = inet_csk(sk);
189         
190         if (what == ICSK_TIME_RETRANS || what == ICSK_TIME_PROBE0) {
191                 icsk->icsk_pending = 0;
192 #ifdef INET_CSK_CLEAR_TIMERS
193                 sk_stop_timer(sk, &icsk->icsk_retransmit_timer);
194 #endif
195         } else if (what == ICSK_TIME_DACK) {
196                 icsk->icsk_ack.blocked = icsk->icsk_ack.pending = 0;
197 #ifdef INET_CSK_CLEAR_TIMERS
198                 sk_stop_timer(sk, &icsk->icsk_delack_timer);
199 #endif
200         }
201 #ifdef INET_CSK_DEBUG
202         else {
203                 pr_debug("%s", inet_csk_timer_bug_msg);
204         }
205 #endif
206 }
207
208 /*
209  *      Reset the retransmission timer
210  */
211 static inline void inet_csk_reset_xmit_timer(struct sock *sk, const int what,
212                                              unsigned long when,
213                                              const unsigned long max_when)
214 {
215         struct inet_connection_sock *icsk = inet_csk(sk);
216
217         if (when > max_when) {
218 #ifdef INET_CSK_DEBUG
219                 pr_debug("reset_xmit_timer: sk=%p %d when=0x%lx, caller=%p\n",
220                          sk, what, when, current_text_addr());
221 #endif
222                 when = max_when;
223         }
224
225         if (what == ICSK_TIME_RETRANS || what == ICSK_TIME_PROBE0) {
226                 icsk->icsk_pending = what;
227                 icsk->icsk_timeout = jiffies + when;
228                 sk_reset_timer(sk, &icsk->icsk_retransmit_timer, icsk->icsk_timeout);
229         } else if (what == ICSK_TIME_DACK) {
230                 icsk->icsk_ack.pending |= ICSK_ACK_TIMER;
231                 icsk->icsk_ack.timeout = jiffies + when;
232                 sk_reset_timer(sk, &icsk->icsk_delack_timer, icsk->icsk_ack.timeout);
233         }
234 #ifdef INET_CSK_DEBUG
235         else {
236                 pr_debug("%s", inet_csk_timer_bug_msg);
237         }
238 #endif
239 }
240
241 extern struct sock *inet_csk_accept(struct sock *sk, int flags, int *err);
242
243 extern struct request_sock *inet_csk_search_req(const struct sock *sk,
244                                                 struct request_sock ***prevp,
245                                                 const __be16 rport,
246                                                 const __be32 raddr,
247                                                 const __be32 laddr);
248 extern int inet_csk_bind_conflict(const struct sock *sk,
249                                   const struct inet_bind_bucket *tb);
250 extern int inet_csk_get_port(struct sock *sk, unsigned short snum);
251
252 extern struct dst_entry* inet_csk_route_req(struct sock *sk,
253                                             const struct request_sock *req);
254
255 static inline void inet_csk_reqsk_queue_add(struct sock *sk,
256                                             struct request_sock *req,
257                                             struct sock *child)
258 {
259         reqsk_queue_add(&inet_csk(sk)->icsk_accept_queue, req, sk, child);
260 }
261
262 extern void inet_csk_reqsk_queue_hash_add(struct sock *sk,
263                                           struct request_sock *req,
264                                           unsigned long timeout);
265
266 static inline void inet_csk_reqsk_queue_removed(struct sock *sk,
267                                                 struct request_sock *req)
268 {
269         if (reqsk_queue_removed(&inet_csk(sk)->icsk_accept_queue, req) == 0)
270                 inet_csk_delete_keepalive_timer(sk);
271 }
272
273 static inline void inet_csk_reqsk_queue_added(struct sock *sk,
274                                               const unsigned long timeout)
275 {
276         if (reqsk_queue_added(&inet_csk(sk)->icsk_accept_queue) == 0)
277                 inet_csk_reset_keepalive_timer(sk, timeout);
278 }
279
280 static inline int inet_csk_reqsk_queue_len(const struct sock *sk)
281 {
282         return reqsk_queue_len(&inet_csk(sk)->icsk_accept_queue);
283 }
284
285 static inline int inet_csk_reqsk_queue_young(const struct sock *sk)
286 {
287         return reqsk_queue_len_young(&inet_csk(sk)->icsk_accept_queue);
288 }
289
290 static inline int inet_csk_reqsk_queue_is_full(const struct sock *sk)
291 {
292         return reqsk_queue_is_full(&inet_csk(sk)->icsk_accept_queue);
293 }
294
295 static inline void inet_csk_reqsk_queue_unlink(struct sock *sk,
296                                                struct request_sock *req,
297                                                struct request_sock **prev)
298 {
299         reqsk_queue_unlink(&inet_csk(sk)->icsk_accept_queue, req, prev);
300 }
301
302 static inline void inet_csk_reqsk_queue_drop(struct sock *sk,
303                                              struct request_sock *req,
304                                              struct request_sock **prev)
305 {
306         inet_csk_reqsk_queue_unlink(sk, req, prev);
307         inet_csk_reqsk_queue_removed(sk, req);
308         reqsk_free(req);
309 }
310
311 extern void inet_csk_reqsk_queue_prune(struct sock *parent,
312                                        const unsigned long interval,
313                                        const unsigned long timeout,
314                                        const unsigned long max_rto);
315
316 extern void inet_csk_destroy_sock(struct sock *sk);
317
318 /*
319  * LISTEN is a special case for poll..
320  */
321 static inline unsigned int inet_csk_listen_poll(const struct sock *sk)
322 {
323         return !reqsk_queue_empty(&inet_csk(sk)->icsk_accept_queue) ?
324                         (POLLIN | POLLRDNORM) : 0;
325 }
326
327 extern int  inet_csk_listen_start(struct sock *sk, const int nr_table_entries);
328 extern void inet_csk_listen_stop(struct sock *sk);
329
330 extern void inet_csk_addr2sockaddr(struct sock *sk, struct sockaddr *uaddr);
331
332 extern int inet_csk_compat_getsockopt(struct sock *sk, int level, int optname,
333                                       char __user *optval, int __user *optlen);
334 extern int inet_csk_compat_setsockopt(struct sock *sk, int level, int optname,
335                                       char __user *optval, unsigned int optlen);
336 #endif /* _INET_CONNECTION_SOCK_H */