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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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 * Definitions for the AF_INET socket handler.
7 *
8 * Version: @(#)sock.h 1.0.4 05/13/93
9 *
Jesper Juhl02c30a82005-05-05 16:16:16 -070010 * Authors: Ross Biro
Linus Torvalds1da177e2005-04-16 15:20:36 -070011 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12 * Corey Minyard <wf-rch!minyard@relay.EU.net>
13 * Florian La Roche <flla@stud.uni-sb.de>
14 *
15 * Fixes:
16 * Alan Cox : Volatiles in skbuff pointers. See
17 * skbuff comments. May be overdone,
18 * better to prove they can be removed
19 * than the reverse.
20 * Alan Cox : Added a zapped field for tcp to note
21 * a socket is reset and must stay shut up
22 * Alan Cox : New fields for options
23 * Pauline Middelink : identd support
24 * Alan Cox : Eliminate low level recv/recvfrom
25 * David S. Miller : New socket lookup architecture.
26 * Steve Whitehouse: Default routines for sock_ops
27 * Arnaldo C. Melo : removed net_pinfo, tp_pinfo and made
28 * protinfo be just a void pointer, as the
29 * protocol specific parts were moved to
30 * respective headers and ipv4/v6, etc now
31 * use private slabcaches for its socks
32 * Pedro Hortas : New flags field for socket options
33 *
34 *
35 * This program is free software; you can redistribute it and/or
36 * modify it under the terms of the GNU General Public License
37 * as published by the Free Software Foundation; either version
38 * 2 of the License, or (at your option) any later version.
39 */
40#ifndef _SOCK_H
41#define _SOCK_H
42
Ilpo Järvinen172589c2007-08-28 15:50:33 -070043#include <linux/kernel.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070044#include <linux/list.h>
45#include <linux/timer.h>
46#include <linux/cache.h>
47#include <linux/module.h>
Ingo Molnara5b5bb92006-07-03 00:25:35 -070048#include <linux/lockdep.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070049#include <linux/netdevice.h>
Arnaldo Carvalho de Meloebb53d72007-11-21 22:08:50 +080050#include <linux/pcounter.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070051#include <linux/skbuff.h> /* struct sk_buff */
Al Virod7fe0f22006-12-03 23:15:30 -050052#include <linux/mm.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070053#include <linux/security.h>
54
55#include <linux/filter.h>
56
57#include <asm/atomic.h>
58#include <net/dst.h>
59#include <net/checksum.h>
60
61/*
62 * This structure really needs to be cleaned up.
63 * Most of it is for TCP, and not used by any of
64 * the other protocols.
65 */
66
67/* Define this to get the SOCK_DBG debugging facility. */
68#define SOCK_DEBUGGING
69#ifdef SOCK_DEBUGGING
70#define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \
71 printk(KERN_DEBUG msg); } while (0)
72#else
73#define SOCK_DEBUG(sk, msg...) do { } while (0)
74#endif
75
76/* This is the per-socket lock. The spinlock provides a synchronization
77 * between user contexts and software interrupt processing, whereas the
78 * mini-semaphore synchronizes multiple users amongst themselves.
79 */
Linus Torvalds1da177e2005-04-16 15:20:36 -070080typedef struct {
81 spinlock_t slock;
John Heffnerd2e91172007-09-12 10:44:19 +020082 int owned;
Linus Torvalds1da177e2005-04-16 15:20:36 -070083 wait_queue_head_t wq;
Ingo Molnara5b5bb92006-07-03 00:25:35 -070084 /*
85 * We express the mutex-alike socket_lock semantics
86 * to the lock validator by explicitly managing
87 * the slock as a lock variant (in addition to
88 * the slock itself):
89 */
90#ifdef CONFIG_DEBUG_LOCK_ALLOC
91 struct lockdep_map dep_map;
92#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -070093} socket_lock_t;
94
Linus Torvalds1da177e2005-04-16 15:20:36 -070095struct sock;
Arnaldo Carvalho de Melo8feaf0c2005-08-09 20:09:30 -070096struct proto;
Denis V. Lunev0eeb8ff2007-12-04 01:15:45 -080097struct net;
Linus Torvalds1da177e2005-04-16 15:20:36 -070098
99/**
Pavel Pisa4dc3b162005-05-01 08:59:25 -0700100 * struct sock_common - minimal network layer representation of sockets
101 * @skc_family: network address family
102 * @skc_state: Connection state
103 * @skc_reuse: %SO_REUSEADDR setting
104 * @skc_bound_dev_if: bound device index if != 0
105 * @skc_node: main hash linkage for various protocol lookup tables
106 * @skc_bind_node: bind hash linkage for various protocol lookup tables
107 * @skc_refcnt: reference count
Eric Dumazet81c3d542005-10-03 14:13:38 -0700108 * @skc_hash: hash value used with various protocol lookup tables
Arnaldo Carvalho de Melo8feaf0c2005-08-09 20:09:30 -0700109 * @skc_prot: protocol handlers inside a network family
Eric W. Biederman07feaeb2007-09-12 11:58:02 +0200110 * @skc_net: reference to the network namespace of this socket
Pavel Pisa4dc3b162005-05-01 08:59:25 -0700111 *
112 * This is the minimal network layer representation of sockets, the header
Arnaldo Carvalho de Melo8feaf0c2005-08-09 20:09:30 -0700113 * for struct sock and struct inet_timewait_sock.
114 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700115struct sock_common {
116 unsigned short skc_family;
117 volatile unsigned char skc_state;
118 unsigned char skc_reuse;
119 int skc_bound_dev_if;
120 struct hlist_node skc_node;
121 struct hlist_node skc_bind_node;
122 atomic_t skc_refcnt;
Eric Dumazet81c3d542005-10-03 14:13:38 -0700123 unsigned int skc_hash;
Arnaldo Carvalho de Melo8feaf0c2005-08-09 20:09:30 -0700124 struct proto *skc_prot;
Eric W. Biederman07feaeb2007-09-12 11:58:02 +0200125 struct net *skc_net;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700126};
127
128/**
129 * struct sock - network layer representation of sockets
Arnaldo Carvalho de Melo8feaf0c2005-08-09 20:09:30 -0700130 * @__sk_common: shared layout with inet_timewait_sock
Pavel Pisa4dc3b162005-05-01 08:59:25 -0700131 * @sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
132 * @sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
133 * @sk_lock: synchronizer
134 * @sk_rcvbuf: size of receive buffer in bytes
135 * @sk_sleep: sock wait queue
136 * @sk_dst_cache: destination cache
137 * @sk_dst_lock: destination cache lock
138 * @sk_policy: flow policy
139 * @sk_rmem_alloc: receive queue bytes committed
140 * @sk_receive_queue: incoming packets
141 * @sk_wmem_alloc: transmit queue bytes committed
142 * @sk_write_queue: Packet sending queue
Chris Leech97fc2f02006-05-23 17:55:33 -0700143 * @sk_async_wait_queue: DMA copied packets
Pavel Pisa4dc3b162005-05-01 08:59:25 -0700144 * @sk_omem_alloc: "o" is "option" or "other"
145 * @sk_wmem_queued: persistent queue size
146 * @sk_forward_alloc: space allocated forward
147 * @sk_allocation: allocation mode
148 * @sk_sndbuf: size of send buffer in bytes
Wang Chen33c732c2007-11-13 20:30:01 -0800149 * @sk_flags: %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE,
150 * %SO_OOBINLINE settings
Pavel Pisa4dc3b162005-05-01 08:59:25 -0700151 * @sk_no_check: %SO_NO_CHECK setting, wether or not checkup packets
152 * @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
Herbert Xubcd76112006-06-30 13:36:35 -0700153 * @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
Pavel Pisa4dc3b162005-05-01 08:59:25 -0700154 * @sk_lingertime: %SO_LINGER l_linger setting
Pavel Pisa4dc3b162005-05-01 08:59:25 -0700155 * @sk_backlog: always used with the per-socket spinlock held
156 * @sk_callback_lock: used with the callbacks in the end of this struct
157 * @sk_error_queue: rarely used
Wang Chen33c732c2007-11-13 20:30:01 -0800158 * @sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt,
159 * IPV6_ADDRFORM for instance)
Pavel Pisa4dc3b162005-05-01 08:59:25 -0700160 * @sk_err: last error
Wang Chen33c732c2007-11-13 20:30:01 -0800161 * @sk_err_soft: errors that don't cause failure but are the cause of a
162 * persistent failure not just 'timed out'
163 * @sk_drops: raw drops counter
Pavel Pisa4dc3b162005-05-01 08:59:25 -0700164 * @sk_ack_backlog: current listen backlog
165 * @sk_max_ack_backlog: listen backlog set in listen()
166 * @sk_priority: %SO_PRIORITY setting
167 * @sk_type: socket type (%SOCK_STREAM, etc)
168 * @sk_protocol: which protocol this socket belongs in this network family
169 * @sk_peercred: %SO_PEERCRED setting
170 * @sk_rcvlowat: %SO_RCVLOWAT setting
171 * @sk_rcvtimeo: %SO_RCVTIMEO setting
172 * @sk_sndtimeo: %SO_SNDTIMEO setting
173 * @sk_filter: socket filtering instructions
174 * @sk_protinfo: private area, net family specific, when not using slab
175 * @sk_timer: sock cleanup timer
176 * @sk_stamp: time stamp of last packet received
177 * @sk_socket: Identd and reporting IO signals
178 * @sk_user_data: RPC layer private data
179 * @sk_sndmsg_page: cached page for sendmsg
180 * @sk_sndmsg_off: cached offset for sendmsg
181 * @sk_send_head: front of stuff to transmit
Martin Waitz67be2dd2005-05-01 08:59:26 -0700182 * @sk_security: used by security modules
Pavel Pisa4dc3b162005-05-01 08:59:25 -0700183 * @sk_write_pending: a write to stream socket waits to start
184 * @sk_state_change: callback to indicate change in the state of the sock
185 * @sk_data_ready: callback to indicate there is data to be processed
186 * @sk_write_space: callback to indicate there is bf sending space available
187 * @sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
188 * @sk_backlog_rcv: callback to process the backlog
189 * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
Linus Torvalds1da177e2005-04-16 15:20:36 -0700190 */
191struct sock {
192 /*
Arnaldo Carvalho de Melo8feaf0c2005-08-09 20:09:30 -0700193 * Now struct inet_timewait_sock also uses sock_common, so please just
Linus Torvalds1da177e2005-04-16 15:20:36 -0700194 * don't add nothing before this first member (__sk_common) --acme
195 */
196 struct sock_common __sk_common;
197#define sk_family __sk_common.skc_family
198#define sk_state __sk_common.skc_state
199#define sk_reuse __sk_common.skc_reuse
200#define sk_bound_dev_if __sk_common.skc_bound_dev_if
201#define sk_node __sk_common.skc_node
202#define sk_bind_node __sk_common.skc_bind_node
203#define sk_refcnt __sk_common.skc_refcnt
Eric Dumazet81c3d542005-10-03 14:13:38 -0700204#define sk_hash __sk_common.skc_hash
Arnaldo Carvalho de Melo8feaf0c2005-08-09 20:09:30 -0700205#define sk_prot __sk_common.skc_prot
Eric W. Biederman07feaeb2007-09-12 11:58:02 +0200206#define sk_net __sk_common.skc_net
Linus Torvalds1da177e2005-04-16 15:20:36 -0700207 unsigned char sk_shutdown : 2,
208 sk_no_check : 2,
209 sk_userlocks : 4;
210 unsigned char sk_protocol;
211 unsigned short sk_type;
212 int sk_rcvbuf;
213 socket_lock_t sk_lock;
Eric Dumazetfa438cc2007-03-04 16:05:44 -0800214 /*
215 * The backlog queue is special, it is always used with
216 * the per-socket spinlock held and requires low latency
217 * access. Therefore we special case it's implementation.
218 */
219 struct {
220 struct sk_buff *head;
221 struct sk_buff *tail;
222 } sk_backlog;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700223 wait_queue_head_t *sk_sleep;
224 struct dst_entry *sk_dst_cache;
225 struct xfrm_policy *sk_policy[2];
226 rwlock_t sk_dst_lock;
227 atomic_t sk_rmem_alloc;
228 atomic_t sk_wmem_alloc;
229 atomic_t sk_omem_alloc;
Arnaldo Carvalho de Melo4e07a912007-05-29 13:17:47 -0700230 int sk_sndbuf;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700231 struct sk_buff_head sk_receive_queue;
232 struct sk_buff_head sk_write_queue;
Chris Leech97fc2f02006-05-23 17:55:33 -0700233 struct sk_buff_head sk_async_wait_queue;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700234 int sk_wmem_queued;
235 int sk_forward_alloc;
Al Viro7d877f32005-10-21 03:20:43 -0400236 gfp_t sk_allocation;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700237 int sk_route_caps;
Herbert Xubcd76112006-06-30 13:36:35 -0700238 int sk_gso_type;
David S. Miller9932cf92006-03-24 15:12:37 -0800239 int sk_rcvlowat;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700240 unsigned long sk_flags;
241 unsigned long sk_lingertime;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700242 struct sk_buff_head sk_error_queue;
Arnaldo Carvalho de Melo476e19c2005-05-05 13:35:15 -0700243 struct proto *sk_prot_creator;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700244 rwlock_t sk_callback_lock;
245 int sk_err,
246 sk_err_soft;
Wang Chen33c732c2007-11-13 20:30:01 -0800247 atomic_t sk_drops;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700248 unsigned short sk_ack_backlog;
249 unsigned short sk_max_ack_backlog;
250 __u32 sk_priority;
251 struct ucred sk_peercred;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700252 long sk_rcvtimeo;
253 long sk_sndtimeo;
254 struct sk_filter *sk_filter;
255 void *sk_protinfo;
256 struct timer_list sk_timer;
Eric Dumazetb7aa0bf2007-04-19 16:16:32 -0700257 ktime_t sk_stamp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700258 struct socket *sk_socket;
259 void *sk_user_data;
260 struct page *sk_sndmsg_page;
261 struct sk_buff *sk_send_head;
262 __u32 sk_sndmsg_off;
263 int sk_write_pending;
264 void *sk_security;
Laszlo Attila Toth4a19ec52008-01-30 19:08:16 -0800265 __u32 sk_mark;
266 /* XXX 4 bytes hole on 64 bit */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700267 void (*sk_state_change)(struct sock *sk);
268 void (*sk_data_ready)(struct sock *sk, int bytes);
269 void (*sk_write_space)(struct sock *sk);
270 void (*sk_error_report)(struct sock *sk);
271 int (*sk_backlog_rcv)(struct sock *sk,
272 struct sk_buff *skb);
273 void (*sk_destruct)(struct sock *sk);
274};
275
276/*
277 * Hashed lists helper routines
278 */
Arnaldo Carvalho de Meloe48c4142005-08-09 20:09:46 -0700279static inline struct sock *__sk_head(const struct hlist_head *head)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700280{
281 return hlist_entry(head->first, struct sock, sk_node);
282}
283
Arnaldo Carvalho de Meloe48c4142005-08-09 20:09:46 -0700284static inline struct sock *sk_head(const struct hlist_head *head)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700285{
286 return hlist_empty(head) ? NULL : __sk_head(head);
287}
288
Arnaldo Carvalho de Meloe48c4142005-08-09 20:09:46 -0700289static inline struct sock *sk_next(const struct sock *sk)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700290{
291 return sk->sk_node.next ?
292 hlist_entry(sk->sk_node.next, struct sock, sk_node) : NULL;
293}
294
Arnaldo Carvalho de Meloe48c4142005-08-09 20:09:46 -0700295static inline int sk_unhashed(const struct sock *sk)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700296{
297 return hlist_unhashed(&sk->sk_node);
298}
299
Arnaldo Carvalho de Meloe48c4142005-08-09 20:09:46 -0700300static inline int sk_hashed(const struct sock *sk)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700301{
Akinobu Mitada753be2006-04-28 15:21:23 -0700302 return !sk_unhashed(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700303}
304
305static __inline__ void sk_node_init(struct hlist_node *node)
306{
307 node->pprev = NULL;
308}
309
310static __inline__ void __sk_del_node(struct sock *sk)
311{
312 __hlist_del(&sk->sk_node);
313}
314
315static __inline__ int __sk_del_node_init(struct sock *sk)
316{
317 if (sk_hashed(sk)) {
318 __sk_del_node(sk);
319 sk_node_init(&sk->sk_node);
320 return 1;
321 }
322 return 0;
323}
324
325/* Grab socket reference count. This operation is valid only
326 when sk is ALREADY grabbed f.e. it is found in hash table
327 or a list and the lookup is made under lock preventing hash table
328 modifications.
329 */
330
331static inline void sock_hold(struct sock *sk)
332{
333 atomic_inc(&sk->sk_refcnt);
334}
335
336/* Ungrab socket in the context, which assumes that socket refcnt
337 cannot hit zero, f.e. it is true in context of any socketcall.
338 */
339static inline void __sock_put(struct sock *sk)
340{
341 atomic_dec(&sk->sk_refcnt);
342}
343
344static __inline__ int sk_del_node_init(struct sock *sk)
345{
346 int rc = __sk_del_node_init(sk);
347
348 if (rc) {
349 /* paranoid for a while -acme */
350 WARN_ON(atomic_read(&sk->sk_refcnt) == 1);
351 __sock_put(sk);
352 }
353 return rc;
354}
355
356static __inline__ void __sk_add_node(struct sock *sk, struct hlist_head *list)
357{
358 hlist_add_head(&sk->sk_node, list);
359}
360
361static __inline__ void sk_add_node(struct sock *sk, struct hlist_head *list)
362{
363 sock_hold(sk);
364 __sk_add_node(sk, list);
365}
366
367static __inline__ void __sk_del_bind_node(struct sock *sk)
368{
369 __hlist_del(&sk->sk_bind_node);
370}
371
372static __inline__ void sk_add_bind_node(struct sock *sk,
373 struct hlist_head *list)
374{
375 hlist_add_head(&sk->sk_bind_node, list);
376}
377
378#define sk_for_each(__sk, node, list) \
379 hlist_for_each_entry(__sk, node, list, sk_node)
380#define sk_for_each_from(__sk, node) \
381 if (__sk && ({ node = &(__sk)->sk_node; 1; })) \
382 hlist_for_each_entry_from(__sk, node, sk_node)
383#define sk_for_each_continue(__sk, node) \
384 if (__sk && ({ node = &(__sk)->sk_node; 1; })) \
385 hlist_for_each_entry_continue(__sk, node, sk_node)
386#define sk_for_each_safe(__sk, node, tmp, list) \
387 hlist_for_each_entry_safe(__sk, node, tmp, list, sk_node)
388#define sk_for_each_bound(__sk, node, list) \
389 hlist_for_each_entry(__sk, node, list, sk_bind_node)
390
391/* Sock flags */
392enum sock_flags {
393 SOCK_DEAD,
394 SOCK_DONE,
395 SOCK_URGINLINE,
396 SOCK_KEEPOPEN,
397 SOCK_LINGER,
398 SOCK_DESTROY,
399 SOCK_BROADCAST,
400 SOCK_TIMESTAMP,
401 SOCK_ZAPPED,
402 SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */
403 SOCK_DBG, /* %SO_DEBUG setting */
404 SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
Eric Dumazet92f37fd2007-03-25 22:14:49 -0700405 SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700406 SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
407 SOCK_QUEUE_SHRUNK, /* write queue has been shrunk recently */
408};
409
Ralf Baechle53b924b2005-08-23 10:11:30 -0700410static inline void sock_copy_flags(struct sock *nsk, struct sock *osk)
411{
412 nsk->sk_flags = osk->sk_flags;
413}
414
Linus Torvalds1da177e2005-04-16 15:20:36 -0700415static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
416{
417 __set_bit(flag, &sk->sk_flags);
418}
419
420static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag)
421{
422 __clear_bit(flag, &sk->sk_flags);
423}
424
425static inline int sock_flag(struct sock *sk, enum sock_flags flag)
426{
427 return test_bit(flag, &sk->sk_flags);
428}
429
430static inline void sk_acceptq_removed(struct sock *sk)
431{
432 sk->sk_ack_backlog--;
433}
434
435static inline void sk_acceptq_added(struct sock *sk)
436{
437 sk->sk_ack_backlog++;
438}
439
440static inline int sk_acceptq_is_full(struct sock *sk)
441{
David S. Miller64a14652007-03-06 11:21:05 -0800442 return sk->sk_ack_backlog > sk->sk_max_ack_backlog;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700443}
444
445/*
446 * Compute minimal free write space needed to queue new packets.
447 */
448static inline int sk_stream_min_wspace(struct sock *sk)
449{
Eric Dumazet8df09ea2007-12-21 03:07:41 -0800450 return sk->sk_wmem_queued >> 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700451}
452
453static inline int sk_stream_wspace(struct sock *sk)
454{
455 return sk->sk_sndbuf - sk->sk_wmem_queued;
456}
457
458extern void sk_stream_write_space(struct sock *sk);
459
460static inline int sk_stream_memory_free(struct sock *sk)
461{
462 return sk->sk_wmem_queued < sk->sk_sndbuf;
463}
464
Linus Torvalds1da177e2005-04-16 15:20:36 -0700465/* The per-socket spinlock must be held here. */
Stephen Hemminger9ee6b532005-11-08 09:39:42 -0800466static inline void sk_add_backlog(struct sock *sk, struct sk_buff *skb)
467{
468 if (!sk->sk_backlog.tail) {
469 sk->sk_backlog.head = sk->sk_backlog.tail = skb;
470 } else {
471 sk->sk_backlog.tail->next = skb;
472 sk->sk_backlog.tail = skb;
473 }
474 skb->next = NULL;
475}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700476
Stephen Hemmingercfcabdc2007-10-09 01:59:42 -0700477#define sk_wait_event(__sk, __timeo, __condition) \
478 ({ int __rc; \
479 release_sock(__sk); \
480 __rc = __condition; \
481 if (!__rc) { \
482 *(__timeo) = schedule_timeout(*(__timeo)); \
483 } \
484 lock_sock(__sk); \
485 __rc = __condition; \
486 __rc; \
487 })
Linus Torvalds1da177e2005-04-16 15:20:36 -0700488
489extern int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
490extern int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
491extern void sk_stream_wait_close(struct sock *sk, long timeo_p);
492extern int sk_stream_error(struct sock *sk, int flags, int err);
493extern void sk_stream_kill_queues(struct sock *sk);
494
495extern int sk_wait_data(struct sock *sk, long *timeo);
496
Arnaldo Carvalho de Melo60236fd2005-06-18 22:47:21 -0700497struct request_sock_ops;
Arnaldo Carvalho de Melo6d6ee432005-12-13 23:25:19 -0800498struct timewait_sock_ops;
Arnaldo Carvalho de Melo2e6599c2005-06-18 22:46:52 -0700499
Linus Torvalds1da177e2005-04-16 15:20:36 -0700500/* Networking protocol blocks we attach to sockets.
501 * socket layer -> transport layer interface
502 * transport -> network interface is defined by struct inet_proto
503 */
504struct proto {
505 void (*close)(struct sock *sk,
506 long timeout);
507 int (*connect)(struct sock *sk,
508 struct sockaddr *uaddr,
509 int addr_len);
510 int (*disconnect)(struct sock *sk, int flags);
511
512 struct sock * (*accept) (struct sock *sk, int flags, int *err);
513
514 int (*ioctl)(struct sock *sk, int cmd,
515 unsigned long arg);
516 int (*init)(struct sock *sk);
517 int (*destroy)(struct sock *sk);
518 void (*shutdown)(struct sock *sk, int how);
519 int (*setsockopt)(struct sock *sk, int level,
520 int optname, char __user *optval,
521 int optlen);
522 int (*getsockopt)(struct sock *sk, int level,
523 int optname, char __user *optval,
524 int __user *option);
Dmitry Mishin3fdadf72006-03-20 22:45:21 -0800525 int (*compat_setsockopt)(struct sock *sk,
526 int level,
527 int optname, char __user *optval,
528 int optlen);
529 int (*compat_getsockopt)(struct sock *sk,
530 int level,
531 int optname, char __user *optval,
532 int __user *option);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700533 int (*sendmsg)(struct kiocb *iocb, struct sock *sk,
534 struct msghdr *msg, size_t len);
535 int (*recvmsg)(struct kiocb *iocb, struct sock *sk,
536 struct msghdr *msg,
537 size_t len, int noblock, int flags,
538 int *addr_len);
539 int (*sendpage)(struct sock *sk, struct page *page,
540 int offset, size_t size, int flags);
541 int (*bind)(struct sock *sk,
542 struct sockaddr *uaddr, int addr_len);
543
544 int (*backlog_rcv) (struct sock *sk,
545 struct sk_buff *skb);
546
547 /* Keeping track of sk's, looking them up, and port selection methods. */
548 void (*hash)(struct sock *sk);
549 void (*unhash)(struct sock *sk);
550 int (*get_port)(struct sock *sk, unsigned short snum);
551
Eric Dumazet286ab3d2007-11-05 23:38:39 -0800552 /* Keeping track of sockets in use */
Eric Dumazet65f76512008-01-03 20:46:48 -0800553#ifdef CONFIG_PROC_FS
Arnaldo Carvalho de Meloebb53d72007-11-21 22:08:50 +0800554 struct pcounter inuse;
Eric Dumazet65f76512008-01-03 20:46:48 -0800555#endif
Arnaldo Carvalho de Meloebb53d72007-11-21 22:08:50 +0800556
Linus Torvalds1da177e2005-04-16 15:20:36 -0700557 /* Memory pressure */
558 void (*enter_memory_pressure)(void);
559 atomic_t *memory_allocated; /* Current allocated memory. */
560 atomic_t *sockets_allocated; /* Current number of sockets. */
561 /*
562 * Pressure flag: try to collapse.
563 * Technical note: it is used by multiple contexts non atomically.
Hideo Aoki3ab224b2007-12-31 00:11:19 -0800564 * All the __sk_mem_schedule() is of this nature: accounting
Linus Torvalds1da177e2005-04-16 15:20:36 -0700565 * is strict, actions are advisory and have some latency.
566 */
567 int *memory_pressure;
568 int *sysctl_mem;
569 int *sysctl_wmem;
570 int *sysctl_rmem;
571 int max_header;
572
Christoph Lametere18b8902006-12-06 20:33:20 -0800573 struct kmem_cache *slab;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700574 unsigned int obj_size;
575
Arnaldo Carvalho de Melo0a5578c2005-08-09 20:11:41 -0700576 atomic_t *orphan_count;
Arnaldo Carvalho de Melo8feaf0c2005-08-09 20:09:30 -0700577
Arnaldo Carvalho de Melo60236fd2005-06-18 22:47:21 -0700578 struct request_sock_ops *rsk_prot;
Arnaldo Carvalho de Melo6d6ee432005-12-13 23:25:19 -0800579 struct timewait_sock_ops *twsk_prot;
Arnaldo Carvalho de Melo2e6599c2005-06-18 22:46:52 -0700580
Linus Torvalds1da177e2005-04-16 15:20:36 -0700581 struct module *owner;
582
583 char name[32];
584
585 struct list_head node;
Arnaldo Carvalho de Meloe6848972005-08-09 19:45:38 -0700586#ifdef SOCK_REFCNT_DEBUG
587 atomic_t socks;
588#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700589};
590
591extern int proto_register(struct proto *prot, int alloc_slab);
592extern void proto_unregister(struct proto *prot);
593
Arnaldo Carvalho de Meloe6848972005-08-09 19:45:38 -0700594#ifdef SOCK_REFCNT_DEBUG
595static inline void sk_refcnt_debug_inc(struct sock *sk)
596{
597 atomic_inc(&sk->sk_prot->socks);
598}
599
600static inline void sk_refcnt_debug_dec(struct sock *sk)
601{
602 atomic_dec(&sk->sk_prot->socks);
603 printk(KERN_DEBUG "%s socket %p released, %d are still alive\n",
604 sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks));
605}
606
607static inline void sk_refcnt_debug_release(const struct sock *sk)
608{
609 if (atomic_read(&sk->sk_refcnt) != 1)
610 printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n",
611 sk->sk_prot->name, sk, atomic_read(&sk->sk_refcnt));
612}
613#else /* SOCK_REFCNT_DEBUG */
614#define sk_refcnt_debug_inc(sk) do { } while (0)
615#define sk_refcnt_debug_dec(sk) do { } while (0)
616#define sk_refcnt_debug_release(sk) do { } while (0)
617#endif /* SOCK_REFCNT_DEBUG */
618
Eric Dumazet65f76512008-01-03 20:46:48 -0800619
620#ifdef CONFIG_PROC_FS
621# define DEFINE_PROTO_INUSE(NAME) DEFINE_PCOUNTER(NAME)
622# define REF_PROTO_INUSE(NAME) PCOUNTER_MEMBER_INITIALIZER(NAME, .inuse)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700623/* Called with local bh disabled */
Eric Dumazet65f76512008-01-03 20:46:48 -0800624static inline void sock_prot_inuse_add(struct proto *prot, int inc)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700625{
Eric Dumazet65f76512008-01-03 20:46:48 -0800626 pcounter_add(&prot->inuse, inc);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700627}
Eric Dumazet65f76512008-01-03 20:46:48 -0800628static inline int sock_prot_inuse_init(struct proto *proto)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700629{
Eric Dumazet65f76512008-01-03 20:46:48 -0800630 return pcounter_alloc(&proto->inuse);
Eric Dumazet286ab3d2007-11-05 23:38:39 -0800631}
Eric Dumazet65f76512008-01-03 20:46:48 -0800632static inline int sock_prot_inuse_get(struct proto *proto)
Eric Dumazet286ab3d2007-11-05 23:38:39 -0800633{
Arnaldo Carvalho de Meloebb53d72007-11-21 22:08:50 +0800634 return pcounter_getval(&proto->inuse);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700635}
Eric Dumazet65f76512008-01-03 20:46:48 -0800636static inline void sock_prot_inuse_free(struct proto *proto)
637{
638 pcounter_free(&proto->inuse);
639}
640#else
641# define DEFINE_PROTO_INUSE(NAME)
642# define REF_PROTO_INUSE(NAME)
643static void inline sock_prot_inuse_add(struct proto *prot, int inc)
644{
645}
646static int inline sock_prot_inuse_init(struct proto *proto)
647{
648 return 0;
649}
650static void inline sock_prot_inuse_free(struct proto *proto)
651{
652}
653#endif
654
Linus Torvalds1da177e2005-04-16 15:20:36 -0700655
Arnaldo Carvalho de Melo614c6cb2005-08-09 19:47:37 -0700656/* With per-bucket locks this operation is not-atomic, so that
657 * this version is not worse.
658 */
659static inline void __sk_prot_rehash(struct sock *sk)
660{
661 sk->sk_prot->unhash(sk);
662 sk->sk_prot->hash(sk);
663}
664
Linus Torvalds1da177e2005-04-16 15:20:36 -0700665/* About 10 seconds */
666#define SOCK_DESTROY_TIME (10*HZ)
667
668/* Sockets 0-1023 can't be bound to unless you are superuser */
669#define PROT_SOCK 1024
670
671#define SHUTDOWN_MASK 3
672#define RCV_SHUTDOWN 1
673#define SEND_SHUTDOWN 2
674
675#define SOCK_SNDBUF_LOCK 1
676#define SOCK_RCVBUF_LOCK 2
677#define SOCK_BINDADDR_LOCK 4
678#define SOCK_BINDPORT_LOCK 8
679
680/* sock_iocb: used to kick off async processing of socket ios */
681struct sock_iocb {
682 struct list_head list;
683
684 int flags;
685 int size;
686 struct socket *sock;
687 struct sock *sk;
688 struct scm_cookie *scm;
689 struct msghdr *msg, async_msg;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700690 struct kiocb *kiocb;
691};
692
693static inline struct sock_iocb *kiocb_to_siocb(struct kiocb *iocb)
694{
695 return (struct sock_iocb *)iocb->private;
696}
697
698static inline struct kiocb *siocb_to_kiocb(struct sock_iocb *si)
699{
700 return si->kiocb;
701}
702
703struct socket_alloc {
704 struct socket socket;
705 struct inode vfs_inode;
706};
707
708static inline struct socket *SOCKET_I(struct inode *inode)
709{
710 return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
711}
712
713static inline struct inode *SOCK_INODE(struct socket *socket)
714{
715 return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
716}
717
Hideo Aoki3ab224b2007-12-31 00:11:19 -0800718/*
719 * Functions for memory accounting
720 */
721extern int __sk_mem_schedule(struct sock *sk, int size, int kind);
722extern void __sk_mem_reclaim(struct sock *sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700723
Hideo Aoki3ab224b2007-12-31 00:11:19 -0800724#define SK_MEM_QUANTUM ((int)PAGE_SIZE)
725#define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM)
726#define SK_MEM_SEND 0
727#define SK_MEM_RECV 1
Linus Torvalds1da177e2005-04-16 15:20:36 -0700728
Hideo Aoki3ab224b2007-12-31 00:11:19 -0800729static inline int sk_mem_pages(int amt)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700730{
Hideo Aoki3ab224b2007-12-31 00:11:19 -0800731 return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700732}
733
Hideo Aoki3ab224b2007-12-31 00:11:19 -0800734static inline int sk_has_account(struct sock *sk)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700735{
Hideo Aoki3ab224b2007-12-31 00:11:19 -0800736 /* return true if protocol supports memory accounting */
737 return !!sk->sk_prot->memory_allocated;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700738}
739
Hideo Aoki3ab224b2007-12-31 00:11:19 -0800740static inline int sk_wmem_schedule(struct sock *sk, int size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700741{
Hideo Aoki3ab224b2007-12-31 00:11:19 -0800742 if (!sk_has_account(sk))
743 return 1;
Herbert Xud80d99d2005-09-01 17:48:23 -0700744 return size <= sk->sk_forward_alloc ||
Hideo Aoki3ab224b2007-12-31 00:11:19 -0800745 __sk_mem_schedule(sk, size, SK_MEM_SEND);
746}
747
748static inline int sk_rmem_schedule(struct sock *sk, int size)
749{
750 if (!sk_has_account(sk))
751 return 1;
752 return size <= sk->sk_forward_alloc ||
753 __sk_mem_schedule(sk, size, SK_MEM_RECV);
754}
755
756static inline void sk_mem_reclaim(struct sock *sk)
757{
758 if (!sk_has_account(sk))
759 return;
760 if (sk->sk_forward_alloc >= SK_MEM_QUANTUM)
761 __sk_mem_reclaim(sk);
762}
763
David S. Miller9993e7d2008-01-10 21:56:38 -0800764static inline void sk_mem_reclaim_partial(struct sock *sk)
765{
766 if (!sk_has_account(sk))
767 return;
768 if (sk->sk_forward_alloc > SK_MEM_QUANTUM)
769 __sk_mem_reclaim(sk);
770}
771
Hideo Aoki3ab224b2007-12-31 00:11:19 -0800772static inline void sk_mem_charge(struct sock *sk, int size)
773{
774 if (!sk_has_account(sk))
775 return;
776 sk->sk_forward_alloc -= size;
777}
778
779static inline void sk_mem_uncharge(struct sock *sk, int size)
780{
781 if (!sk_has_account(sk))
782 return;
783 sk->sk_forward_alloc += size;
784}
785
786static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb)
787{
788 skb_truesize_check(skb);
789 sock_set_flag(sk, SOCK_QUEUE_SHRUNK);
790 sk->sk_wmem_queued -= skb->truesize;
791 sk_mem_uncharge(sk, skb->truesize);
792 __kfree_skb(skb);
Herbert Xud80d99d2005-09-01 17:48:23 -0700793}
794
Linus Torvalds1da177e2005-04-16 15:20:36 -0700795/* Used by processes to "lock" a socket state, so that
796 * interrupts and bottom half handlers won't change it
797 * from under us. It essentially blocks any incoming
798 * packets, so that we won't get any new data or any
799 * packets that change the state of the socket.
800 *
801 * While locked, BH processing will add new packets to
802 * the backlog queue. This queue is processed by the
803 * owner of the socket lock right before it is released.
804 *
805 * Since ~2.3.5 it is also exclusive sleep lock serializing
806 * accesses from user process context.
807 */
John Heffnerd2e91172007-09-12 10:44:19 +0200808#define sock_owned_by_user(sk) ((sk)->sk_lock.owned)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700809
Peter Zijlstraed075362006-12-06 20:35:24 -0800810/*
811 * Macro so as to not evaluate some arguments when
812 * lockdep is not enabled.
813 *
814 * Mark both the sk_lock and the sk_lock.slock as a
815 * per-address-family lock class.
816 */
817#define sock_lock_init_class_and_name(sk, sname, skey, name, key) \
818do { \
John Heffnerd2e91172007-09-12 10:44:19 +0200819 sk->sk_lock.owned = 0; \
Peter Zijlstraed075362006-12-06 20:35:24 -0800820 init_waitqueue_head(&sk->sk_lock.wq); \
821 spin_lock_init(&(sk)->sk_lock.slock); \
822 debug_check_no_locks_freed((void *)&(sk)->sk_lock, \
823 sizeof((sk)->sk_lock)); \
824 lockdep_set_class_and_name(&(sk)->sk_lock.slock, \
825 (skey), (sname)); \
826 lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \
827} while (0)
828
Harvey Harrison41380932007-12-12 10:46:51 -0800829extern void lock_sock_nested(struct sock *sk, int subclass);
Peter Zijlstrafcc70d52006-11-08 22:44:35 -0800830
831static inline void lock_sock(struct sock *sk)
832{
833 lock_sock_nested(sk, 0);
834}
835
Harvey Harrison41380932007-12-12 10:46:51 -0800836extern void release_sock(struct sock *sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700837
838/* BH context may only use the following locking interface. */
839#define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock))
Ingo Molnarc6366182006-07-03 00:25:13 -0700840#define bh_lock_sock_nested(__sk) \
841 spin_lock_nested(&((__sk)->sk_lock.slock), \
842 SINGLE_DEPTH_NESTING)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700843#define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock))
844
Eric W. Biederman1b8d7ae2007-10-08 23:24:22 -0700845extern struct sock *sk_alloc(struct net *net, int family,
Al Virodd0fc662005-10-07 07:46:04 +0100846 gfp_t priority,
Pavel Emelyanov6257ff22007-11-01 00:39:31 -0700847 struct proto *prot);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700848extern void sk_free(struct sock *sk);
Arnaldo Carvalho de Melo87d11ce2005-08-09 20:10:12 -0700849extern struct sock *sk_clone(const struct sock *sk,
Al Virodd0fc662005-10-07 07:46:04 +0100850 const gfp_t priority);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700851
852extern struct sk_buff *sock_wmalloc(struct sock *sk,
853 unsigned long size, int force,
Al Virodd0fc662005-10-07 07:46:04 +0100854 gfp_t priority);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700855extern struct sk_buff *sock_rmalloc(struct sock *sk,
856 unsigned long size, int force,
Al Virodd0fc662005-10-07 07:46:04 +0100857 gfp_t priority);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700858extern void sock_wfree(struct sk_buff *skb);
859extern void sock_rfree(struct sk_buff *skb);
860
861extern int sock_setsockopt(struct socket *sock, int level,
862 int op, char __user *optval,
863 int optlen);
864
865extern int sock_getsockopt(struct socket *sock, int level,
866 int op, char __user *optval,
867 int __user *optlen);
868extern struct sk_buff *sock_alloc_send_skb(struct sock *sk,
869 unsigned long size,
870 int noblock,
871 int *errcode);
Victor Fusco86a76ca2005-07-08 14:57:47 -0700872extern void *sock_kmalloc(struct sock *sk, int size,
Al Virodd0fc662005-10-07 07:46:04 +0100873 gfp_t priority);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700874extern void sock_kfree_s(struct sock *sk, void *mem, int size);
875extern void sk_send_sigurg(struct sock *sk);
876
877/*
878 * Functions to fill in entries in struct proto_ops when a protocol
879 * does not implement a particular function.
880 */
881extern int sock_no_bind(struct socket *,
882 struct sockaddr *, int);
883extern int sock_no_connect(struct socket *,
884 struct sockaddr *, int, int);
885extern int sock_no_socketpair(struct socket *,
886 struct socket *);
887extern int sock_no_accept(struct socket *,
888 struct socket *, int);
889extern int sock_no_getname(struct socket *,
890 struct sockaddr *, int *, int);
891extern unsigned int sock_no_poll(struct file *, struct socket *,
892 struct poll_table_struct *);
893extern int sock_no_ioctl(struct socket *, unsigned int,
894 unsigned long);
895extern int sock_no_listen(struct socket *, int);
896extern int sock_no_shutdown(struct socket *, int);
897extern int sock_no_getsockopt(struct socket *, int , int,
898 char __user *, int __user *);
899extern int sock_no_setsockopt(struct socket *, int, int,
900 char __user *, int);
901extern int sock_no_sendmsg(struct kiocb *, struct socket *,
902 struct msghdr *, size_t);
903extern int sock_no_recvmsg(struct kiocb *, struct socket *,
904 struct msghdr *, size_t, int);
905extern int sock_no_mmap(struct file *file,
906 struct socket *sock,
907 struct vm_area_struct *vma);
908extern ssize_t sock_no_sendpage(struct socket *sock,
909 struct page *page,
910 int offset, size_t size,
911 int flags);
912
913/*
914 * Functions to fill in entries in struct proto_ops when a protocol
915 * uses the inet style.
916 */
917extern int sock_common_getsockopt(struct socket *sock, int level, int optname,
918 char __user *optval, int __user *optlen);
919extern int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock,
920 struct msghdr *msg, size_t size, int flags);
921extern int sock_common_setsockopt(struct socket *sock, int level, int optname,
922 char __user *optval, int optlen);
Dmitry Mishin3fdadf72006-03-20 22:45:21 -0800923extern int compat_sock_common_getsockopt(struct socket *sock, int level,
924 int optname, char __user *optval, int __user *optlen);
925extern int compat_sock_common_setsockopt(struct socket *sock, int level,
926 int optname, char __user *optval, int optlen);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700927
928extern void sk_common_release(struct sock *sk);
929
930/*
931 * Default socket callbacks and setup code
932 */
933
934/* Initialise core socket variables */
935extern void sock_init_data(struct socket *sock, struct sock *sk);
936
937/**
938 * sk_filter - run a packet through a socket filter
939 * @sk: sock associated with &sk_buff
940 * @skb: buffer to filter
941 * @needlock: set to 1 if the sock is not locked by caller.
942 *
943 * Run the filter code and then cut skb->data to correct size returned by
944 * sk_run_filter. If pkt_len is 0 we toss packet. If skb->len is smaller
945 * than pkt_len we keep whole skb->data. This is the socket level
946 * wrapper to sk_run_filter. It returns 0 if the packet should
947 * be accepted or -EPERM if the packet should be tossed.
948 *
949 */
950
Dmitry Mishinfda9ef52006-08-31 15:28:39 -0700951static inline int sk_filter(struct sock *sk, struct sk_buff *skb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700952{
953 int err;
Dmitry Mishinfda9ef52006-08-31 15:28:39 -0700954 struct sk_filter *filter;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700955
956 err = security_sock_rcv_skb(sk, skb);
957 if (err)
958 return err;
959
Dmitry Mishinfda9ef52006-08-31 15:28:39 -0700960 rcu_read_lock_bh();
Eric Dumazet9d3e4442008-01-08 23:41:28 -0800961 filter = rcu_dereference(sk->sk_filter);
Dmitry Mishinfda9ef52006-08-31 15:28:39 -0700962 if (filter) {
963 unsigned int pkt_len = sk_run_filter(skb, filter->insns,
964 filter->len);
965 err = pkt_len ? pskb_trim(skb, pkt_len) : -EPERM;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700966 }
Dmitry Mishinfda9ef52006-08-31 15:28:39 -0700967 rcu_read_unlock_bh();
968
Linus Torvalds1da177e2005-04-16 15:20:36 -0700969 return err;
970}
971
972/**
Paul Bonserdc9b3342006-11-23 17:56:13 -0800973 * sk_filter_release: Release a socket filter
974 * @sk: socket
975 * @fp: filter to remove
976 *
977 * Remove a filter from a socket and release its resources.
978 */
979
Pavel Emelyanov309dd5f2007-10-17 21:21:51 -0700980static inline void sk_filter_release(struct sk_filter *fp)
981{
982 if (atomic_dec_and_test(&fp->refcnt))
Pavel Emelyanov47e958e2007-10-17 21:22:42 -0700983 kfree(fp);
Pavel Emelyanov309dd5f2007-10-17 21:21:51 -0700984}
985
986static inline void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700987{
988 unsigned int size = sk_filter_len(fp);
989
990 atomic_sub(size, &sk->sk_omem_alloc);
Pavel Emelyanov309dd5f2007-10-17 21:21:51 -0700991 sk_filter_release(fp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700992}
993
994static inline void sk_filter_charge(struct sock *sk, struct sk_filter *fp)
995{
996 atomic_inc(&fp->refcnt);
997 atomic_add(sk_filter_len(fp), &sk->sk_omem_alloc);
998}
999
1000/*
1001 * Socket reference counting postulates.
1002 *
1003 * * Each user of socket SHOULD hold a reference count.
1004 * * Each access point to socket (an hash table bucket, reference from a list,
1005 * running timer, skb in flight MUST hold a reference count.
1006 * * When reference count hits 0, it means it will never increase back.
1007 * * When reference count hits 0, it means that no references from
1008 * outside exist to this socket and current process on current CPU
1009 * is last user and may/should destroy this socket.
1010 * * sk_free is called from any context: process, BH, IRQ. When
1011 * it is called, socket has no references from outside -> sk_free
1012 * may release descendant resources allocated by the socket, but
1013 * to the time when it is called, socket is NOT referenced by any
1014 * hash tables, lists etc.
1015 * * Packets, delivered from outside (from network or from another process)
1016 * and enqueued on receive/error queues SHOULD NOT grab reference count,
1017 * when they sit in queue. Otherwise, packets will leak to hole, when
1018 * socket is looked up by one cpu and unhasing is made by another CPU.
1019 * It is true for udp/raw, netlink (leak to receive and error queues), tcp
1020 * (leak to backlog). Packet socket does all the processing inside
1021 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
1022 * use separate SMP lock, so that they are prone too.
1023 */
1024
1025/* Ungrab socket and destroy it, if it was the last reference. */
1026static inline void sock_put(struct sock *sk)
1027{
1028 if (atomic_dec_and_test(&sk->sk_refcnt))
1029 sk_free(sk);
1030}
1031
Arnaldo Carvalho de Melo58a5a7b2006-11-16 14:06:06 -02001032extern int sk_receive_skb(struct sock *sk, struct sk_buff *skb,
1033 const int nested);
Arnaldo Carvalho de Melo25995ff2005-12-27 02:42:22 -02001034
Linus Torvalds1da177e2005-04-16 15:20:36 -07001035/* Detach socket from process context.
1036 * Announce socket dead, detach it from wait queue and inode.
1037 * Note that parent inode held reference count on this struct sock,
1038 * we do not release it in this function, because protocol
1039 * probably wants some additional cleanups or even continuing
1040 * to work with this socket (TCP).
1041 */
1042static inline void sock_orphan(struct sock *sk)
1043{
1044 write_lock_bh(&sk->sk_callback_lock);
1045 sock_set_flag(sk, SOCK_DEAD);
1046 sk->sk_socket = NULL;
1047 sk->sk_sleep = NULL;
1048 write_unlock_bh(&sk->sk_callback_lock);
1049}
1050
1051static inline void sock_graft(struct sock *sk, struct socket *parent)
1052{
1053 write_lock_bh(&sk->sk_callback_lock);
1054 sk->sk_sleep = &parent->wait;
1055 parent->sk = sk;
1056 sk->sk_socket = parent;
Venkat Yekkirala4237c752006-07-24 23:32:50 -07001057 security_sock_graft(sk, parent);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001058 write_unlock_bh(&sk->sk_callback_lock);
1059}
1060
1061extern int sock_i_uid(struct sock *sk);
1062extern unsigned long sock_i_ino(struct sock *sk);
1063
1064static inline struct dst_entry *
1065__sk_dst_get(struct sock *sk)
1066{
1067 return sk->sk_dst_cache;
1068}
1069
1070static inline struct dst_entry *
1071sk_dst_get(struct sock *sk)
1072{
1073 struct dst_entry *dst;
1074
1075 read_lock(&sk->sk_dst_lock);
1076 dst = sk->sk_dst_cache;
1077 if (dst)
1078 dst_hold(dst);
1079 read_unlock(&sk->sk_dst_lock);
1080 return dst;
1081}
1082
1083static inline void
1084__sk_dst_set(struct sock *sk, struct dst_entry *dst)
1085{
1086 struct dst_entry *old_dst;
1087
1088 old_dst = sk->sk_dst_cache;
1089 sk->sk_dst_cache = dst;
1090 dst_release(old_dst);
1091}
1092
1093static inline void
1094sk_dst_set(struct sock *sk, struct dst_entry *dst)
1095{
1096 write_lock(&sk->sk_dst_lock);
1097 __sk_dst_set(sk, dst);
1098 write_unlock(&sk->sk_dst_lock);
1099}
1100
1101static inline void
1102__sk_dst_reset(struct sock *sk)
1103{
1104 struct dst_entry *old_dst;
1105
1106 old_dst = sk->sk_dst_cache;
1107 sk->sk_dst_cache = NULL;
1108 dst_release(old_dst);
1109}
1110
1111static inline void
1112sk_dst_reset(struct sock *sk)
1113{
1114 write_lock(&sk->sk_dst_lock);
1115 __sk_dst_reset(sk);
1116 write_unlock(&sk->sk_dst_lock);
1117}
1118
Denis Vlasenkof0088a52006-03-28 01:08:21 -08001119extern struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001120
Denis Vlasenkof0088a52006-03-28 01:08:21 -08001121extern struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001122
Herbert Xubcd76112006-06-30 13:36:35 -07001123static inline int sk_can_gso(const struct sock *sk)
1124{
1125 return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type);
1126}
1127
Andi Kleen99580892007-04-20 17:12:43 -07001128extern void sk_setup_caps(struct sock *sk, struct dst_entry *dst);
Arnaldo Carvalho de Melo6cbb0df2005-08-09 19:49:02 -07001129
Linus Torvalds1da177e2005-04-16 15:20:36 -07001130static inline int skb_copy_to_page(struct sock *sk, char __user *from,
1131 struct sk_buff *skb, struct page *page,
1132 int off, int copy)
1133{
1134 if (skb->ip_summed == CHECKSUM_NONE) {
1135 int err = 0;
Al Viro50842052006-11-14 21:36:34 -08001136 __wsum csum = csum_and_copy_from_user(from,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001137 page_address(page) + off,
1138 copy, 0, &err);
1139 if (err)
1140 return err;
1141 skb->csum = csum_block_add(skb->csum, csum, skb->len);
1142 } else if (copy_from_user(page_address(page) + off, from, copy))
1143 return -EFAULT;
1144
1145 skb->len += copy;
1146 skb->data_len += copy;
1147 skb->truesize += copy;
1148 sk->sk_wmem_queued += copy;
Hideo Aoki3ab224b2007-12-31 00:11:19 -08001149 sk_mem_charge(sk, copy);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001150 return 0;
1151}
1152
1153/*
1154 * Queue a received datagram if it will fit. Stream and sequenced
1155 * protocols can't normally use this as they need to fit buffers in
1156 * and play with them.
1157 *
1158 * Inlined as it's very short and called for pretty much every
1159 * packet ever received.
1160 */
1161
1162static inline void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
1163{
1164 sock_hold(sk);
1165 skb->sk = sk;
1166 skb->destructor = sock_wfree;
1167 atomic_add(skb->truesize, &sk->sk_wmem_alloc);
1168}
1169
1170static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
1171{
1172 skb->sk = sk;
1173 skb->destructor = sock_rfree;
1174 atomic_add(skb->truesize, &sk->sk_rmem_alloc);
Hideo Aoki3ab224b2007-12-31 00:11:19 -08001175 sk_mem_charge(sk, skb->truesize);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001176}
1177
1178extern void sk_reset_timer(struct sock *sk, struct timer_list* timer,
1179 unsigned long expires);
1180
1181extern void sk_stop_timer(struct sock *sk, struct timer_list* timer);
1182
Denis Vlasenkof0088a52006-03-28 01:08:21 -08001183extern int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001184
1185static inline int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb)
1186{
1187 /* Cast skb->rcvbuf to unsigned... It's pointless, but reduces
1188 number of warnings when compiling with -W --ANK
1189 */
1190 if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >=
1191 (unsigned)sk->sk_rcvbuf)
1192 return -ENOMEM;
1193 skb_set_owner_r(skb, sk);
1194 skb_queue_tail(&sk->sk_error_queue, skb);
1195 if (!sock_flag(sk, SOCK_DEAD))
1196 sk->sk_data_ready(sk, skb->len);
1197 return 0;
1198}
1199
1200/*
1201 * Recover an error report and clear atomically
1202 */
1203
1204static inline int sock_error(struct sock *sk)
1205{
Benjamin LaHaisec1cbe4b2005-12-13 23:22:19 -08001206 int err;
1207 if (likely(!sk->sk_err))
1208 return 0;
1209 err = xchg(&sk->sk_err, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001210 return -err;
1211}
1212
1213static inline unsigned long sock_wspace(struct sock *sk)
1214{
1215 int amt = 0;
1216
1217 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
1218 amt = sk->sk_sndbuf - atomic_read(&sk->sk_wmem_alloc);
1219 if (amt < 0)
1220 amt = 0;
1221 }
1222 return amt;
1223}
1224
1225static inline void sk_wake_async(struct sock *sk, int how, int band)
1226{
1227 if (sk->sk_socket && sk->sk_socket->fasync_list)
1228 sock_wake_async(sk->sk_socket, how, band);
1229}
1230
1231#define SOCK_MIN_SNDBUF 2048
1232#define SOCK_MIN_RCVBUF 256
1233
1234static inline void sk_stream_moderate_sndbuf(struct sock *sk)
1235{
1236 if (!(sk->sk_userlocks & SOCK_SNDBUF_LOCK)) {
Eric Dumazet8df09ea2007-12-21 03:07:41 -08001237 sk->sk_sndbuf = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001238 sk->sk_sndbuf = max(sk->sk_sndbuf, SOCK_MIN_SNDBUF);
1239 }
1240}
1241
Pavel Emelyanovdf97c702007-11-29 21:22:33 +11001242struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001243
1244static inline struct page *sk_stream_alloc_page(struct sock *sk)
1245{
1246 struct page *page = NULL;
1247
Herbert Xuef015782005-09-01 17:48:59 -07001248 page = alloc_pages(sk->sk_allocation, 0);
1249 if (!page) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001250 sk->sk_prot->enter_memory_pressure();
1251 sk_stream_moderate_sndbuf(sk);
1252 }
1253 return page;
1254}
1255
Linus Torvalds1da177e2005-04-16 15:20:36 -07001256/*
1257 * Default write policy as shown to user space via poll/select/SIGIO
1258 */
1259static inline int sock_writeable(const struct sock *sk)
1260{
Eric Dumazet8df09ea2007-12-21 03:07:41 -08001261 return atomic_read(&sk->sk_wmem_alloc) < (sk->sk_sndbuf >> 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001262}
1263
Al Virodd0fc662005-10-07 07:46:04 +01001264static inline gfp_t gfp_any(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001265{
Patrick McHardy44981212007-02-27 09:56:42 -08001266 return in_atomic() ? GFP_ATOMIC : GFP_KERNEL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001267}
1268
1269static inline long sock_rcvtimeo(const struct sock *sk, int noblock)
1270{
1271 return noblock ? 0 : sk->sk_rcvtimeo;
1272}
1273
1274static inline long sock_sndtimeo(const struct sock *sk, int noblock)
1275{
1276 return noblock ? 0 : sk->sk_sndtimeo;
1277}
1278
1279static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
1280{
1281 return (waitall ? len : min_t(int, sk->sk_rcvlowat, len)) ? : 1;
1282}
1283
1284/* Alas, with timeout socket operations are not restartable.
1285 * Compare this to poll().
1286 */
1287static inline int sock_intr_errno(long timeo)
1288{
1289 return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
1290}
1291
Eric Dumazet92f37fd2007-03-25 22:14:49 -07001292extern void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
1293 struct sk_buff *skb);
1294
Linus Torvalds1da177e2005-04-16 15:20:36 -07001295static __inline__ void
1296sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
1297{
Eric Dumazetb7aa0bf2007-04-19 16:16:32 -07001298 ktime_t kt = skb->tstamp;
Patrick McHardya61bbcf2005-08-14 17:24:31 -07001299
Eric Dumazet92f37fd2007-03-25 22:14:49 -07001300 if (sock_flag(sk, SOCK_RCVTSTAMP))
1301 __sock_recv_timestamp(msg, sk, skb);
1302 else
Eric Dumazetb7aa0bf2007-04-19 16:16:32 -07001303 sk->sk_stamp = kt;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001304}
1305
1306/**
1307 * sk_eat_skb - Release a skb if it is no longer needed
Pavel Pisa4dc3b162005-05-01 08:59:25 -07001308 * @sk: socket to eat this skb from
1309 * @skb: socket buffer to eat
Randy Dunlapf4b8ea72006-06-22 16:00:11 -07001310 * @copied_early: flag indicating whether DMA operations copied this data early
Linus Torvalds1da177e2005-04-16 15:20:36 -07001311 *
1312 * This routine must be called with interrupts disabled or with the socket
1313 * locked so that the sk_buff queue operation is ok.
1314*/
Chris Leech624d1162006-05-23 18:01:28 -07001315#ifdef CONFIG_NET_DMA
1316static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb, int copied_early)
1317{
1318 __skb_unlink(skb, &sk->sk_receive_queue);
1319 if (!copied_early)
1320 __kfree_skb(skb);
1321 else
1322 __skb_queue_tail(&sk->sk_async_wait_queue, skb);
1323}
1324#else
1325static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb, int copied_early)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001326{
1327 __skb_unlink(skb, &sk->sk_receive_queue);
1328 __kfree_skb(skb);
1329}
Chris Leech624d1162006-05-23 18:01:28 -07001330#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07001331
1332extern void sock_enable_timestamp(struct sock *sk);
1333extern int sock_get_timestamp(struct sock *, struct timeval __user *);
Eric Dumazetae40eb12007-03-18 17:33:16 -07001334extern int sock_get_timestampns(struct sock *, struct timespec __user *);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001335
1336/*
1337 * Enable debug/info messages
1338 */
Stephen Hemmingera2a316f2007-03-08 20:41:08 -08001339extern int net_msg_warn;
1340#define NETDEBUG(fmt, args...) \
1341 do { if (net_msg_warn) printk(fmt,##args); } while (0)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001342
Stephen Hemmingera2a316f2007-03-08 20:41:08 -08001343#define LIMIT_NETDEBUG(fmt, args...) \
1344 do { if (net_msg_warn && net_ratelimit()) printk(fmt,##args); } while(0)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001345
1346/*
1347 * Macros for sleeping on a socket. Use them like this:
1348 *
1349 * SOCK_SLEEP_PRE(sk)
1350 * if (condition)
1351 * schedule();
1352 * SOCK_SLEEP_POST(sk)
1353 *
1354 * N.B. These are now obsolete and were, afaik, only ever used in DECnet
1355 * and when the last use of them in DECnet has gone, I'm intending to
1356 * remove them.
1357 */
1358
1359#define SOCK_SLEEP_PRE(sk) { struct task_struct *tsk = current; \
1360 DECLARE_WAITQUEUE(wait, tsk); \
1361 tsk->state = TASK_INTERRUPTIBLE; \
1362 add_wait_queue((sk)->sk_sleep, &wait); \
1363 release_sock(sk);
1364
1365#define SOCK_SLEEP_POST(sk) tsk->state = TASK_RUNNING; \
1366 remove_wait_queue((sk)->sk_sleep, &wait); \
1367 lock_sock(sk); \
1368 }
1369
Linus Torvalds1da177e2005-04-16 15:20:36 -07001370extern __u32 sysctl_wmem_max;
1371extern __u32 sysctl_rmem_max;
1372
Arnaldo Carvalho de Melo20380732005-08-16 02:18:02 -03001373extern void sk_init(void);
1374
David S. Miller6baf1f42005-09-05 18:14:11 -07001375extern int sysctl_optmem_max;
1376
Arnaldo Carvalho de Melo20380732005-08-16 02:18:02 -03001377extern __u32 sysctl_wmem_default;
1378extern __u32 sysctl_rmem_default;
Arnaldo Carvalho de Melo20380732005-08-16 02:18:02 -03001379
Linus Torvalds1da177e2005-04-16 15:20:36 -07001380#endif /* _SOCK_H */