xref: /linux/include/net/sock.h (revision de2fe5e07d58424bc286fff3fd3c1b0bf933cd58)
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  *		Definitions for the AF_INET socket handler.
7  *
8  * Version:	@(#)sock.h	1.0.4	05/13/93
9  *
10  * Authors:	Ross Biro
11  *		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 
43 #include <linux/config.h>
44 #include <linux/list.h>
45 #include <linux/timer.h>
46 #include <linux/cache.h>
47 #include <linux/module.h>
48 #include <linux/netdevice.h>
49 #include <linux/skbuff.h>	/* struct sk_buff */
50 #include <linux/security.h>
51 
52 #include <linux/filter.h>
53 
54 #include <asm/atomic.h>
55 #include <net/dst.h>
56 #include <net/checksum.h>
57 
58 /*
59  * This structure really needs to be cleaned up.
60  * Most of it is for TCP, and not used by any of
61  * the other protocols.
62  */
63 
64 /* Define this to get the SOCK_DBG debugging facility. */
65 #define SOCK_DEBUGGING
66 #ifdef SOCK_DEBUGGING
67 #define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \
68 					printk(KERN_DEBUG msg); } while (0)
69 #else
70 #define SOCK_DEBUG(sk, msg...) do { } while (0)
71 #endif
72 
73 /* This is the per-socket lock.  The spinlock provides a synchronization
74  * between user contexts and software interrupt processing, whereas the
75  * mini-semaphore synchronizes multiple users amongst themselves.
76  */
77 struct sock_iocb;
78 typedef struct {
79 	spinlock_t		slock;
80 	struct sock_iocb	*owner;
81 	wait_queue_head_t	wq;
82 } socket_lock_t;
83 
84 #define sock_lock_init(__sk) \
85 do {	spin_lock_init(&((__sk)->sk_lock.slock)); \
86 	(__sk)->sk_lock.owner = NULL; \
87 	init_waitqueue_head(&((__sk)->sk_lock.wq)); \
88 } while(0)
89 
90 struct sock;
91 struct proto;
92 
93 /**
94  *	struct sock_common - minimal network layer representation of sockets
95  *	@skc_family: network address family
96  *	@skc_state: Connection state
97  *	@skc_reuse: %SO_REUSEADDR setting
98  *	@skc_bound_dev_if: bound device index if != 0
99  *	@skc_node: main hash linkage for various protocol lookup tables
100  *	@skc_bind_node: bind hash linkage for various protocol lookup tables
101  *	@skc_refcnt: reference count
102  *	@skc_hash: hash value used with various protocol lookup tables
103  *	@skc_prot: protocol handlers inside a network family
104  *
105  *	This is the minimal network layer representation of sockets, the header
106  *	for struct sock and struct inet_timewait_sock.
107  */
108 struct sock_common {
109 	unsigned short		skc_family;
110 	volatile unsigned char	skc_state;
111 	unsigned char		skc_reuse;
112 	int			skc_bound_dev_if;
113 	struct hlist_node	skc_node;
114 	struct hlist_node	skc_bind_node;
115 	atomic_t		skc_refcnt;
116 	unsigned int		skc_hash;
117 	struct proto		*skc_prot;
118 };
119 
120 /**
121   *	struct sock - network layer representation of sockets
122   *	@__sk_common: shared layout with inet_timewait_sock
123   *	@sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
124   *	@sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
125   *	@sk_lock:	synchronizer
126   *	@sk_rcvbuf: size of receive buffer in bytes
127   *	@sk_sleep: sock wait queue
128   *	@sk_dst_cache: destination cache
129   *	@sk_dst_lock: destination cache lock
130   *	@sk_policy: flow policy
131   *	@sk_rmem_alloc: receive queue bytes committed
132   *	@sk_receive_queue: incoming packets
133   *	@sk_wmem_alloc: transmit queue bytes committed
134   *	@sk_write_queue: Packet sending queue
135   *	@sk_omem_alloc: "o" is "option" or "other"
136   *	@sk_wmem_queued: persistent queue size
137   *	@sk_forward_alloc: space allocated forward
138   *	@sk_allocation: allocation mode
139   *	@sk_sndbuf: size of send buffer in bytes
140   *	@sk_flags: %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE, %SO_OOBINLINE settings
141   *	@sk_no_check: %SO_NO_CHECK setting, wether or not checkup packets
142   *	@sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
143   *	@sk_lingertime: %SO_LINGER l_linger setting
144   *	@sk_backlog: always used with the per-socket spinlock held
145   *	@sk_callback_lock: used with the callbacks in the end of this struct
146   *	@sk_error_queue: rarely used
147   *	@sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt, IPV6_ADDRFORM for instance)
148   *	@sk_err: last error
149   *	@sk_err_soft: errors that don't cause failure but are the cause of a persistent failure not just 'timed out'
150   *	@sk_ack_backlog: current listen backlog
151   *	@sk_max_ack_backlog: listen backlog set in listen()
152   *	@sk_priority: %SO_PRIORITY setting
153   *	@sk_type: socket type (%SOCK_STREAM, etc)
154   *	@sk_protocol: which protocol this socket belongs in this network family
155   *	@sk_peercred: %SO_PEERCRED setting
156   *	@sk_rcvlowat: %SO_RCVLOWAT setting
157   *	@sk_rcvtimeo: %SO_RCVTIMEO setting
158   *	@sk_sndtimeo: %SO_SNDTIMEO setting
159   *	@sk_filter: socket filtering instructions
160   *	@sk_protinfo: private area, net family specific, when not using slab
161   *	@sk_timer: sock cleanup timer
162   *	@sk_stamp: time stamp of last packet received
163   *	@sk_socket: Identd and reporting IO signals
164   *	@sk_user_data: RPC layer private data
165   *	@sk_sndmsg_page: cached page for sendmsg
166   *	@sk_sndmsg_off: cached offset for sendmsg
167   *	@sk_send_head: front of stuff to transmit
168   *	@sk_security: used by security modules
169   *	@sk_write_pending: a write to stream socket waits to start
170   *	@sk_state_change: callback to indicate change in the state of the sock
171   *	@sk_data_ready: callback to indicate there is data to be processed
172   *	@sk_write_space: callback to indicate there is bf sending space available
173   *	@sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
174   *	@sk_backlog_rcv: callback to process the backlog
175   *	@sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
176  */
177 struct sock {
178 	/*
179 	 * Now struct inet_timewait_sock also uses sock_common, so please just
180 	 * don't add nothing before this first member (__sk_common) --acme
181 	 */
182 	struct sock_common	__sk_common;
183 #define sk_family		__sk_common.skc_family
184 #define sk_state		__sk_common.skc_state
185 #define sk_reuse		__sk_common.skc_reuse
186 #define sk_bound_dev_if		__sk_common.skc_bound_dev_if
187 #define sk_node			__sk_common.skc_node
188 #define sk_bind_node		__sk_common.skc_bind_node
189 #define sk_refcnt		__sk_common.skc_refcnt
190 #define sk_hash			__sk_common.skc_hash
191 #define sk_prot			__sk_common.skc_prot
192 	unsigned char		sk_shutdown : 2,
193 				sk_no_check : 2,
194 				sk_userlocks : 4;
195 	unsigned char		sk_protocol;
196 	unsigned short		sk_type;
197 	int			sk_rcvbuf;
198 	socket_lock_t		sk_lock;
199 	wait_queue_head_t	*sk_sleep;
200 	struct dst_entry	*sk_dst_cache;
201 	struct xfrm_policy	*sk_policy[2];
202 	rwlock_t		sk_dst_lock;
203 	atomic_t		sk_rmem_alloc;
204 	atomic_t		sk_wmem_alloc;
205 	atomic_t		sk_omem_alloc;
206 	struct sk_buff_head	sk_receive_queue;
207 	struct sk_buff_head	sk_write_queue;
208 	int			sk_wmem_queued;
209 	int			sk_forward_alloc;
210 	gfp_t			sk_allocation;
211 	int			sk_sndbuf;
212 	int			sk_route_caps;
213 	int			sk_rcvlowat;
214 	unsigned long 		sk_flags;
215 	unsigned long	        sk_lingertime;
216 	/*
217 	 * The backlog queue is special, it is always used with
218 	 * the per-socket spinlock held and requires low latency
219 	 * access. Therefore we special case it's implementation.
220 	 */
221 	struct {
222 		struct sk_buff *head;
223 		struct sk_buff *tail;
224 	} sk_backlog;
225 	struct sk_buff_head	sk_error_queue;
226 	struct proto		*sk_prot_creator;
227 	rwlock_t		sk_callback_lock;
228 	int			sk_err,
229 				sk_err_soft;
230 	unsigned short		sk_ack_backlog;
231 	unsigned short		sk_max_ack_backlog;
232 	__u32			sk_priority;
233 	struct ucred		sk_peercred;
234 	long			sk_rcvtimeo;
235 	long			sk_sndtimeo;
236 	struct sk_filter      	*sk_filter;
237 	void			*sk_protinfo;
238 	struct timer_list	sk_timer;
239 	struct timeval		sk_stamp;
240 	struct socket		*sk_socket;
241 	void			*sk_user_data;
242 	struct page		*sk_sndmsg_page;
243 	struct sk_buff		*sk_send_head;
244 	__u32			sk_sndmsg_off;
245 	int			sk_write_pending;
246 	void			*sk_security;
247 	void			(*sk_state_change)(struct sock *sk);
248 	void			(*sk_data_ready)(struct sock *sk, int bytes);
249 	void			(*sk_write_space)(struct sock *sk);
250 	void			(*sk_error_report)(struct sock *sk);
251   	int			(*sk_backlog_rcv)(struct sock *sk,
252 						  struct sk_buff *skb);
253 	void                    (*sk_destruct)(struct sock *sk);
254 };
255 
256 /*
257  * Hashed lists helper routines
258  */
259 static inline struct sock *__sk_head(const struct hlist_head *head)
260 {
261 	return hlist_entry(head->first, struct sock, sk_node);
262 }
263 
264 static inline struct sock *sk_head(const struct hlist_head *head)
265 {
266 	return hlist_empty(head) ? NULL : __sk_head(head);
267 }
268 
269 static inline struct sock *sk_next(const struct sock *sk)
270 {
271 	return sk->sk_node.next ?
272 		hlist_entry(sk->sk_node.next, struct sock, sk_node) : NULL;
273 }
274 
275 static inline int sk_unhashed(const struct sock *sk)
276 {
277 	return hlist_unhashed(&sk->sk_node);
278 }
279 
280 static inline int sk_hashed(const struct sock *sk)
281 {
282 	return sk->sk_node.pprev != NULL;
283 }
284 
285 static __inline__ void sk_node_init(struct hlist_node *node)
286 {
287 	node->pprev = NULL;
288 }
289 
290 static __inline__ void __sk_del_node(struct sock *sk)
291 {
292 	__hlist_del(&sk->sk_node);
293 }
294 
295 static __inline__ int __sk_del_node_init(struct sock *sk)
296 {
297 	if (sk_hashed(sk)) {
298 		__sk_del_node(sk);
299 		sk_node_init(&sk->sk_node);
300 		return 1;
301 	}
302 	return 0;
303 }
304 
305 /* Grab socket reference count. This operation is valid only
306    when sk is ALREADY grabbed f.e. it is found in hash table
307    or a list and the lookup is made under lock preventing hash table
308    modifications.
309  */
310 
311 static inline void sock_hold(struct sock *sk)
312 {
313 	atomic_inc(&sk->sk_refcnt);
314 }
315 
316 /* Ungrab socket in the context, which assumes that socket refcnt
317    cannot hit zero, f.e. it is true in context of any socketcall.
318  */
319 static inline void __sock_put(struct sock *sk)
320 {
321 	atomic_dec(&sk->sk_refcnt);
322 }
323 
324 static __inline__ int sk_del_node_init(struct sock *sk)
325 {
326 	int rc = __sk_del_node_init(sk);
327 
328 	if (rc) {
329 		/* paranoid for a while -acme */
330 		WARN_ON(atomic_read(&sk->sk_refcnt) == 1);
331 		__sock_put(sk);
332 	}
333 	return rc;
334 }
335 
336 static __inline__ void __sk_add_node(struct sock *sk, struct hlist_head *list)
337 {
338 	hlist_add_head(&sk->sk_node, list);
339 }
340 
341 static __inline__ void sk_add_node(struct sock *sk, struct hlist_head *list)
342 {
343 	sock_hold(sk);
344 	__sk_add_node(sk, list);
345 }
346 
347 static __inline__ void __sk_del_bind_node(struct sock *sk)
348 {
349 	__hlist_del(&sk->sk_bind_node);
350 }
351 
352 static __inline__ void sk_add_bind_node(struct sock *sk,
353 					struct hlist_head *list)
354 {
355 	hlist_add_head(&sk->sk_bind_node, list);
356 }
357 
358 #define sk_for_each(__sk, node, list) \
359 	hlist_for_each_entry(__sk, node, list, sk_node)
360 #define sk_for_each_from(__sk, node) \
361 	if (__sk && ({ node = &(__sk)->sk_node; 1; })) \
362 		hlist_for_each_entry_from(__sk, node, sk_node)
363 #define sk_for_each_continue(__sk, node) \
364 	if (__sk && ({ node = &(__sk)->sk_node; 1; })) \
365 		hlist_for_each_entry_continue(__sk, node, sk_node)
366 #define sk_for_each_safe(__sk, node, tmp, list) \
367 	hlist_for_each_entry_safe(__sk, node, tmp, list, sk_node)
368 #define sk_for_each_bound(__sk, node, list) \
369 	hlist_for_each_entry(__sk, node, list, sk_bind_node)
370 
371 /* Sock flags */
372 enum sock_flags {
373 	SOCK_DEAD,
374 	SOCK_DONE,
375 	SOCK_URGINLINE,
376 	SOCK_KEEPOPEN,
377 	SOCK_LINGER,
378 	SOCK_DESTROY,
379 	SOCK_BROADCAST,
380 	SOCK_TIMESTAMP,
381 	SOCK_ZAPPED,
382 	SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */
383 	SOCK_DBG, /* %SO_DEBUG setting */
384 	SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
385 	SOCK_NO_LARGESEND, /* whether to sent large segments or not */
386 	SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
387 	SOCK_QUEUE_SHRUNK, /* write queue has been shrunk recently */
388 };
389 
390 static inline void sock_copy_flags(struct sock *nsk, struct sock *osk)
391 {
392 	nsk->sk_flags = osk->sk_flags;
393 }
394 
395 static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
396 {
397 	__set_bit(flag, &sk->sk_flags);
398 }
399 
400 static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag)
401 {
402 	__clear_bit(flag, &sk->sk_flags);
403 }
404 
405 static inline int sock_flag(struct sock *sk, enum sock_flags flag)
406 {
407 	return test_bit(flag, &sk->sk_flags);
408 }
409 
410 static inline void sk_acceptq_removed(struct sock *sk)
411 {
412 	sk->sk_ack_backlog--;
413 }
414 
415 static inline void sk_acceptq_added(struct sock *sk)
416 {
417 	sk->sk_ack_backlog++;
418 }
419 
420 static inline int sk_acceptq_is_full(struct sock *sk)
421 {
422 	return sk->sk_ack_backlog > sk->sk_max_ack_backlog;
423 }
424 
425 /*
426  * Compute minimal free write space needed to queue new packets.
427  */
428 static inline int sk_stream_min_wspace(struct sock *sk)
429 {
430 	return sk->sk_wmem_queued / 2;
431 }
432 
433 static inline int sk_stream_wspace(struct sock *sk)
434 {
435 	return sk->sk_sndbuf - sk->sk_wmem_queued;
436 }
437 
438 extern void sk_stream_write_space(struct sock *sk);
439 
440 static inline int sk_stream_memory_free(struct sock *sk)
441 {
442 	return sk->sk_wmem_queued < sk->sk_sndbuf;
443 }
444 
445 extern void sk_stream_rfree(struct sk_buff *skb);
446 
447 static inline void sk_stream_set_owner_r(struct sk_buff *skb, struct sock *sk)
448 {
449 	skb->sk = sk;
450 	skb->destructor = sk_stream_rfree;
451 	atomic_add(skb->truesize, &sk->sk_rmem_alloc);
452 	sk->sk_forward_alloc -= skb->truesize;
453 }
454 
455 static inline void sk_stream_free_skb(struct sock *sk, struct sk_buff *skb)
456 {
457 	sock_set_flag(sk, SOCK_QUEUE_SHRUNK);
458 	sk->sk_wmem_queued   -= skb->truesize;
459 	sk->sk_forward_alloc += skb->truesize;
460 	__kfree_skb(skb);
461 }
462 
463 /* The per-socket spinlock must be held here. */
464 static inline void sk_add_backlog(struct sock *sk, struct sk_buff *skb)
465 {
466 	if (!sk->sk_backlog.tail) {
467 		sk->sk_backlog.head = sk->sk_backlog.tail = skb;
468 	} else {
469 		sk->sk_backlog.tail->next = skb;
470 		sk->sk_backlog.tail = skb;
471 	}
472 	skb->next = NULL;
473 }
474 
475 #define sk_wait_event(__sk, __timeo, __condition)		\
476 ({	int rc;							\
477 	release_sock(__sk);					\
478 	rc = __condition;					\
479 	if (!rc) {						\
480 		*(__timeo) = schedule_timeout(*(__timeo));	\
481 	}							\
482 	lock_sock(__sk);					\
483 	rc = __condition;					\
484 	rc;							\
485 })
486 
487 extern int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
488 extern int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
489 extern void sk_stream_wait_close(struct sock *sk, long timeo_p);
490 extern int sk_stream_error(struct sock *sk, int flags, int err);
491 extern void sk_stream_kill_queues(struct sock *sk);
492 
493 extern int sk_wait_data(struct sock *sk, long *timeo);
494 
495 struct request_sock_ops;
496 struct timewait_sock_ops;
497 
498 /* Networking protocol blocks we attach to sockets.
499  * socket layer -> transport layer interface
500  * transport -> network interface is defined by struct inet_proto
501  */
502 struct proto {
503 	void			(*close)(struct sock *sk,
504 					long timeout);
505 	int			(*connect)(struct sock *sk,
506 				        struct sockaddr *uaddr,
507 					int addr_len);
508 	int			(*disconnect)(struct sock *sk, int flags);
509 
510 	struct sock *		(*accept) (struct sock *sk, int flags, int *err);
511 
512 	int			(*ioctl)(struct sock *sk, int cmd,
513 					 unsigned long arg);
514 	int			(*init)(struct sock *sk);
515 	int			(*destroy)(struct sock *sk);
516 	void			(*shutdown)(struct sock *sk, int how);
517 	int			(*setsockopt)(struct sock *sk, int level,
518 					int optname, char __user *optval,
519 					int optlen);
520 	int			(*getsockopt)(struct sock *sk, int level,
521 					int optname, char __user *optval,
522 					int __user *option);
523 	int			(*compat_setsockopt)(struct sock *sk,
524 					int level,
525 					int optname, char __user *optval,
526 					int optlen);
527 	int			(*compat_getsockopt)(struct sock *sk,
528 					int level,
529 					int optname, char __user *optval,
530 					int __user *option);
531 	int			(*sendmsg)(struct kiocb *iocb, struct sock *sk,
532 					   struct msghdr *msg, size_t len);
533 	int			(*recvmsg)(struct kiocb *iocb, struct sock *sk,
534 					   struct msghdr *msg,
535 					size_t len, int noblock, int flags,
536 					int *addr_len);
537 	int			(*sendpage)(struct sock *sk, struct page *page,
538 					int offset, size_t size, int flags);
539 	int			(*bind)(struct sock *sk,
540 					struct sockaddr *uaddr, int addr_len);
541 
542 	int			(*backlog_rcv) (struct sock *sk,
543 						struct sk_buff *skb);
544 
545 	/* Keeping track of sk's, looking them up, and port selection methods. */
546 	void			(*hash)(struct sock *sk);
547 	void			(*unhash)(struct sock *sk);
548 	int			(*get_port)(struct sock *sk, unsigned short snum);
549 
550 	/* Memory pressure */
551 	void			(*enter_memory_pressure)(void);
552 	atomic_t		*memory_allocated;	/* Current allocated memory. */
553 	atomic_t		*sockets_allocated;	/* Current number of sockets. */
554 	/*
555 	 * Pressure flag: try to collapse.
556 	 * Technical note: it is used by multiple contexts non atomically.
557 	 * All the sk_stream_mem_schedule() is of this nature: accounting
558 	 * is strict, actions are advisory and have some latency.
559 	 */
560 	int			*memory_pressure;
561 	int			*sysctl_mem;
562 	int			*sysctl_wmem;
563 	int			*sysctl_rmem;
564 	int			max_header;
565 
566 	kmem_cache_t		*slab;
567 	unsigned int		obj_size;
568 
569 	atomic_t		*orphan_count;
570 
571 	struct request_sock_ops	*rsk_prot;
572 	struct timewait_sock_ops *twsk_prot;
573 
574 	struct module		*owner;
575 
576 	char			name[32];
577 
578 	struct list_head	node;
579 #ifdef SOCK_REFCNT_DEBUG
580 	atomic_t		socks;
581 #endif
582 	struct {
583 		int inuse;
584 		u8  __pad[SMP_CACHE_BYTES - sizeof(int)];
585 	} stats[NR_CPUS];
586 };
587 
588 extern int proto_register(struct proto *prot, int alloc_slab);
589 extern void proto_unregister(struct proto *prot);
590 
591 #ifdef SOCK_REFCNT_DEBUG
592 static inline void sk_refcnt_debug_inc(struct sock *sk)
593 {
594 	atomic_inc(&sk->sk_prot->socks);
595 }
596 
597 static inline void sk_refcnt_debug_dec(struct sock *sk)
598 {
599 	atomic_dec(&sk->sk_prot->socks);
600 	printk(KERN_DEBUG "%s socket %p released, %d are still alive\n",
601 	       sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks));
602 }
603 
604 static inline void sk_refcnt_debug_release(const struct sock *sk)
605 {
606 	if (atomic_read(&sk->sk_refcnt) != 1)
607 		printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n",
608 		       sk->sk_prot->name, sk, atomic_read(&sk->sk_refcnt));
609 }
610 #else /* SOCK_REFCNT_DEBUG */
611 #define sk_refcnt_debug_inc(sk) do { } while (0)
612 #define sk_refcnt_debug_dec(sk) do { } while (0)
613 #define sk_refcnt_debug_release(sk) do { } while (0)
614 #endif /* SOCK_REFCNT_DEBUG */
615 
616 /* Called with local bh disabled */
617 static __inline__ void sock_prot_inc_use(struct proto *prot)
618 {
619 	prot->stats[smp_processor_id()].inuse++;
620 }
621 
622 static __inline__ void sock_prot_dec_use(struct proto *prot)
623 {
624 	prot->stats[smp_processor_id()].inuse--;
625 }
626 
627 /* With per-bucket locks this operation is not-atomic, so that
628  * this version is not worse.
629  */
630 static inline void __sk_prot_rehash(struct sock *sk)
631 {
632 	sk->sk_prot->unhash(sk);
633 	sk->sk_prot->hash(sk);
634 }
635 
636 /* About 10 seconds */
637 #define SOCK_DESTROY_TIME (10*HZ)
638 
639 /* Sockets 0-1023 can't be bound to unless you are superuser */
640 #define PROT_SOCK	1024
641 
642 #define SHUTDOWN_MASK	3
643 #define RCV_SHUTDOWN	1
644 #define SEND_SHUTDOWN	2
645 
646 #define SOCK_SNDBUF_LOCK	1
647 #define SOCK_RCVBUF_LOCK	2
648 #define SOCK_BINDADDR_LOCK	4
649 #define SOCK_BINDPORT_LOCK	8
650 
651 /* sock_iocb: used to kick off async processing of socket ios */
652 struct sock_iocb {
653 	struct list_head	list;
654 
655 	int			flags;
656 	int			size;
657 	struct socket		*sock;
658 	struct sock		*sk;
659 	struct scm_cookie	*scm;
660 	struct msghdr		*msg, async_msg;
661 	struct iovec		async_iov;
662 	struct kiocb		*kiocb;
663 };
664 
665 static inline struct sock_iocb *kiocb_to_siocb(struct kiocb *iocb)
666 {
667 	return (struct sock_iocb *)iocb->private;
668 }
669 
670 static inline struct kiocb *siocb_to_kiocb(struct sock_iocb *si)
671 {
672 	return si->kiocb;
673 }
674 
675 struct socket_alloc {
676 	struct socket socket;
677 	struct inode vfs_inode;
678 };
679 
680 static inline struct socket *SOCKET_I(struct inode *inode)
681 {
682 	return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
683 }
684 
685 static inline struct inode *SOCK_INODE(struct socket *socket)
686 {
687 	return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
688 }
689 
690 extern void __sk_stream_mem_reclaim(struct sock *sk);
691 extern int sk_stream_mem_schedule(struct sock *sk, int size, int kind);
692 
693 #define SK_STREAM_MEM_QUANTUM ((int)PAGE_SIZE)
694 
695 static inline int sk_stream_pages(int amt)
696 {
697 	return (amt + SK_STREAM_MEM_QUANTUM - 1) / SK_STREAM_MEM_QUANTUM;
698 }
699 
700 static inline void sk_stream_mem_reclaim(struct sock *sk)
701 {
702 	if (sk->sk_forward_alloc >= SK_STREAM_MEM_QUANTUM)
703 		__sk_stream_mem_reclaim(sk);
704 }
705 
706 static inline void sk_stream_writequeue_purge(struct sock *sk)
707 {
708 	struct sk_buff *skb;
709 
710 	while ((skb = __skb_dequeue(&sk->sk_write_queue)) != NULL)
711 		sk_stream_free_skb(sk, skb);
712 	sk_stream_mem_reclaim(sk);
713 }
714 
715 static inline int sk_stream_rmem_schedule(struct sock *sk, struct sk_buff *skb)
716 {
717 	return (int)skb->truesize <= sk->sk_forward_alloc ||
718 		sk_stream_mem_schedule(sk, skb->truesize, 1);
719 }
720 
721 static inline int sk_stream_wmem_schedule(struct sock *sk, int size)
722 {
723 	return size <= sk->sk_forward_alloc ||
724 	       sk_stream_mem_schedule(sk, size, 0);
725 }
726 
727 /* Used by processes to "lock" a socket state, so that
728  * interrupts and bottom half handlers won't change it
729  * from under us. It essentially blocks any incoming
730  * packets, so that we won't get any new data or any
731  * packets that change the state of the socket.
732  *
733  * While locked, BH processing will add new packets to
734  * the backlog queue.  This queue is processed by the
735  * owner of the socket lock right before it is released.
736  *
737  * Since ~2.3.5 it is also exclusive sleep lock serializing
738  * accesses from user process context.
739  */
740 #define sock_owned_by_user(sk)	((sk)->sk_lock.owner)
741 
742 extern void FASTCALL(lock_sock(struct sock *sk));
743 extern void FASTCALL(release_sock(struct sock *sk));
744 
745 /* BH context may only use the following locking interface. */
746 #define bh_lock_sock(__sk)	spin_lock(&((__sk)->sk_lock.slock))
747 #define bh_unlock_sock(__sk)	spin_unlock(&((__sk)->sk_lock.slock))
748 
749 extern struct sock		*sk_alloc(int family,
750 					  gfp_t priority,
751 					  struct proto *prot, int zero_it);
752 extern void			sk_free(struct sock *sk);
753 extern struct sock		*sk_clone(const struct sock *sk,
754 					  const gfp_t priority);
755 
756 extern struct sk_buff		*sock_wmalloc(struct sock *sk,
757 					      unsigned long size, int force,
758 					      gfp_t priority);
759 extern struct sk_buff		*sock_rmalloc(struct sock *sk,
760 					      unsigned long size, int force,
761 					      gfp_t priority);
762 extern void			sock_wfree(struct sk_buff *skb);
763 extern void			sock_rfree(struct sk_buff *skb);
764 
765 extern int			sock_setsockopt(struct socket *sock, int level,
766 						int op, char __user *optval,
767 						int optlen);
768 
769 extern int			sock_getsockopt(struct socket *sock, int level,
770 						int op, char __user *optval,
771 						int __user *optlen);
772 extern struct sk_buff 		*sock_alloc_send_skb(struct sock *sk,
773 						     unsigned long size,
774 						     int noblock,
775 						     int *errcode);
776 extern void *sock_kmalloc(struct sock *sk, int size,
777 			  gfp_t priority);
778 extern void sock_kfree_s(struct sock *sk, void *mem, int size);
779 extern void sk_send_sigurg(struct sock *sk);
780 
781 /*
782  * Functions to fill in entries in struct proto_ops when a protocol
783  * does not implement a particular function.
784  */
785 extern int                      sock_no_bind(struct socket *,
786 					     struct sockaddr *, int);
787 extern int                      sock_no_connect(struct socket *,
788 						struct sockaddr *, int, int);
789 extern int                      sock_no_socketpair(struct socket *,
790 						   struct socket *);
791 extern int                      sock_no_accept(struct socket *,
792 					       struct socket *, int);
793 extern int                      sock_no_getname(struct socket *,
794 						struct sockaddr *, int *, int);
795 extern unsigned int             sock_no_poll(struct file *, struct socket *,
796 					     struct poll_table_struct *);
797 extern int                      sock_no_ioctl(struct socket *, unsigned int,
798 					      unsigned long);
799 extern int			sock_no_listen(struct socket *, int);
800 extern int                      sock_no_shutdown(struct socket *, int);
801 extern int			sock_no_getsockopt(struct socket *, int , int,
802 						   char __user *, int __user *);
803 extern int			sock_no_setsockopt(struct socket *, int, int,
804 						   char __user *, int);
805 extern int                      sock_no_sendmsg(struct kiocb *, struct socket *,
806 						struct msghdr *, size_t);
807 extern int                      sock_no_recvmsg(struct kiocb *, struct socket *,
808 						struct msghdr *, size_t, int);
809 extern int			sock_no_mmap(struct file *file,
810 					     struct socket *sock,
811 					     struct vm_area_struct *vma);
812 extern ssize_t			sock_no_sendpage(struct socket *sock,
813 						struct page *page,
814 						int offset, size_t size,
815 						int flags);
816 
817 /*
818  * Functions to fill in entries in struct proto_ops when a protocol
819  * uses the inet style.
820  */
821 extern int sock_common_getsockopt(struct socket *sock, int level, int optname,
822 				  char __user *optval, int __user *optlen);
823 extern int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock,
824 			       struct msghdr *msg, size_t size, int flags);
825 extern int sock_common_setsockopt(struct socket *sock, int level, int optname,
826 				  char __user *optval, int optlen);
827 extern int compat_sock_common_getsockopt(struct socket *sock, int level,
828 		int optname, char __user *optval, int __user *optlen);
829 extern int compat_sock_common_setsockopt(struct socket *sock, int level,
830 		int optname, char __user *optval, int optlen);
831 
832 extern void sk_common_release(struct sock *sk);
833 
834 /*
835  *	Default socket callbacks and setup code
836  */
837 
838 /* Initialise core socket variables */
839 extern void sock_init_data(struct socket *sock, struct sock *sk);
840 
841 /**
842  *	sk_filter - run a packet through a socket filter
843  *	@sk: sock associated with &sk_buff
844  *	@skb: buffer to filter
845  *	@needlock: set to 1 if the sock is not locked by caller.
846  *
847  * Run the filter code and then cut skb->data to correct size returned by
848  * sk_run_filter. If pkt_len is 0 we toss packet. If skb->len is smaller
849  * than pkt_len we keep whole skb->data. This is the socket level
850  * wrapper to sk_run_filter. It returns 0 if the packet should
851  * be accepted or -EPERM if the packet should be tossed.
852  *
853  */
854 
855 static inline int sk_filter(struct sock *sk, struct sk_buff *skb, int needlock)
856 {
857 	int err;
858 
859 	err = security_sock_rcv_skb(sk, skb);
860 	if (err)
861 		return err;
862 
863 	if (sk->sk_filter) {
864 		struct sk_filter *filter;
865 
866 		if (needlock)
867 			bh_lock_sock(sk);
868 
869 		filter = sk->sk_filter;
870 		if (filter) {
871 			unsigned int pkt_len = sk_run_filter(skb, filter->insns,
872 							     filter->len);
873 			if (!pkt_len)
874 				err = -EPERM;
875 			else
876 				skb_trim(skb, pkt_len);
877 		}
878 
879 		if (needlock)
880 			bh_unlock_sock(sk);
881 	}
882 	return err;
883 }
884 
885 /**
886  *	sk_filter_release: Release a socket filter
887  *	@sk: socket
888  *	@fp: filter to remove
889  *
890  *	Remove a filter from a socket and release its resources.
891  */
892 
893 static inline void sk_filter_release(struct sock *sk, struct sk_filter *fp)
894 {
895 	unsigned int size = sk_filter_len(fp);
896 
897 	atomic_sub(size, &sk->sk_omem_alloc);
898 
899 	if (atomic_dec_and_test(&fp->refcnt))
900 		kfree(fp);
901 }
902 
903 static inline void sk_filter_charge(struct sock *sk, struct sk_filter *fp)
904 {
905 	atomic_inc(&fp->refcnt);
906 	atomic_add(sk_filter_len(fp), &sk->sk_omem_alloc);
907 }
908 
909 /*
910  * Socket reference counting postulates.
911  *
912  * * Each user of socket SHOULD hold a reference count.
913  * * Each access point to socket (an hash table bucket, reference from a list,
914  *   running timer, skb in flight MUST hold a reference count.
915  * * When reference count hits 0, it means it will never increase back.
916  * * When reference count hits 0, it means that no references from
917  *   outside exist to this socket and current process on current CPU
918  *   is last user and may/should destroy this socket.
919  * * sk_free is called from any context: process, BH, IRQ. When
920  *   it is called, socket has no references from outside -> sk_free
921  *   may release descendant resources allocated by the socket, but
922  *   to the time when it is called, socket is NOT referenced by any
923  *   hash tables, lists etc.
924  * * Packets, delivered from outside (from network or from another process)
925  *   and enqueued on receive/error queues SHOULD NOT grab reference count,
926  *   when they sit in queue. Otherwise, packets will leak to hole, when
927  *   socket is looked up by one cpu and unhasing is made by another CPU.
928  *   It is true for udp/raw, netlink (leak to receive and error queues), tcp
929  *   (leak to backlog). Packet socket does all the processing inside
930  *   BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
931  *   use separate SMP lock, so that they are prone too.
932  */
933 
934 /* Ungrab socket and destroy it, if it was the last reference. */
935 static inline void sock_put(struct sock *sk)
936 {
937 	if (atomic_dec_and_test(&sk->sk_refcnt))
938 		sk_free(sk);
939 }
940 
941 extern int sk_receive_skb(struct sock *sk, struct sk_buff *skb);
942 
943 /* Detach socket from process context.
944  * Announce socket dead, detach it from wait queue and inode.
945  * Note that parent inode held reference count on this struct sock,
946  * we do not release it in this function, because protocol
947  * probably wants some additional cleanups or even continuing
948  * to work with this socket (TCP).
949  */
950 static inline void sock_orphan(struct sock *sk)
951 {
952 	write_lock_bh(&sk->sk_callback_lock);
953 	sock_set_flag(sk, SOCK_DEAD);
954 	sk->sk_socket = NULL;
955 	sk->sk_sleep  = NULL;
956 	write_unlock_bh(&sk->sk_callback_lock);
957 }
958 
959 static inline void sock_graft(struct sock *sk, struct socket *parent)
960 {
961 	write_lock_bh(&sk->sk_callback_lock);
962 	sk->sk_sleep = &parent->wait;
963 	parent->sk = sk;
964 	sk->sk_socket = parent;
965 	write_unlock_bh(&sk->sk_callback_lock);
966 }
967 
968 extern int sock_i_uid(struct sock *sk);
969 extern unsigned long sock_i_ino(struct sock *sk);
970 
971 static inline struct dst_entry *
972 __sk_dst_get(struct sock *sk)
973 {
974 	return sk->sk_dst_cache;
975 }
976 
977 static inline struct dst_entry *
978 sk_dst_get(struct sock *sk)
979 {
980 	struct dst_entry *dst;
981 
982 	read_lock(&sk->sk_dst_lock);
983 	dst = sk->sk_dst_cache;
984 	if (dst)
985 		dst_hold(dst);
986 	read_unlock(&sk->sk_dst_lock);
987 	return dst;
988 }
989 
990 static inline void
991 __sk_dst_set(struct sock *sk, struct dst_entry *dst)
992 {
993 	struct dst_entry *old_dst;
994 
995 	old_dst = sk->sk_dst_cache;
996 	sk->sk_dst_cache = dst;
997 	dst_release(old_dst);
998 }
999 
1000 static inline void
1001 sk_dst_set(struct sock *sk, struct dst_entry *dst)
1002 {
1003 	write_lock(&sk->sk_dst_lock);
1004 	__sk_dst_set(sk, dst);
1005 	write_unlock(&sk->sk_dst_lock);
1006 }
1007 
1008 static inline void
1009 __sk_dst_reset(struct sock *sk)
1010 {
1011 	struct dst_entry *old_dst;
1012 
1013 	old_dst = sk->sk_dst_cache;
1014 	sk->sk_dst_cache = NULL;
1015 	dst_release(old_dst);
1016 }
1017 
1018 static inline void
1019 sk_dst_reset(struct sock *sk)
1020 {
1021 	write_lock(&sk->sk_dst_lock);
1022 	__sk_dst_reset(sk);
1023 	write_unlock(&sk->sk_dst_lock);
1024 }
1025 
1026 extern struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
1027 
1028 extern struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
1029 
1030 static inline void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
1031 {
1032 	__sk_dst_set(sk, dst);
1033 	sk->sk_route_caps = dst->dev->features;
1034 	if (sk->sk_route_caps & NETIF_F_TSO) {
1035 		if (sock_flag(sk, SOCK_NO_LARGESEND) || dst->header_len)
1036 			sk->sk_route_caps &= ~NETIF_F_TSO;
1037 	}
1038 }
1039 
1040 static inline void sk_charge_skb(struct sock *sk, struct sk_buff *skb)
1041 {
1042 	sk->sk_wmem_queued   += skb->truesize;
1043 	sk->sk_forward_alloc -= skb->truesize;
1044 }
1045 
1046 static inline int skb_copy_to_page(struct sock *sk, char __user *from,
1047 				   struct sk_buff *skb, struct page *page,
1048 				   int off, int copy)
1049 {
1050 	if (skb->ip_summed == CHECKSUM_NONE) {
1051 		int err = 0;
1052 		unsigned int csum = csum_and_copy_from_user(from,
1053 						     page_address(page) + off,
1054 							    copy, 0, &err);
1055 		if (err)
1056 			return err;
1057 		skb->csum = csum_block_add(skb->csum, csum, skb->len);
1058 	} else if (copy_from_user(page_address(page) + off, from, copy))
1059 		return -EFAULT;
1060 
1061 	skb->len	     += copy;
1062 	skb->data_len	     += copy;
1063 	skb->truesize	     += copy;
1064 	sk->sk_wmem_queued   += copy;
1065 	sk->sk_forward_alloc -= copy;
1066 	return 0;
1067 }
1068 
1069 /*
1070  * 	Queue a received datagram if it will fit. Stream and sequenced
1071  *	protocols can't normally use this as they need to fit buffers in
1072  *	and play with them.
1073  *
1074  * 	Inlined as it's very short and called for pretty much every
1075  *	packet ever received.
1076  */
1077 
1078 static inline void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
1079 {
1080 	sock_hold(sk);
1081 	skb->sk = sk;
1082 	skb->destructor = sock_wfree;
1083 	atomic_add(skb->truesize, &sk->sk_wmem_alloc);
1084 }
1085 
1086 static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
1087 {
1088 	skb->sk = sk;
1089 	skb->destructor = sock_rfree;
1090 	atomic_add(skb->truesize, &sk->sk_rmem_alloc);
1091 }
1092 
1093 extern void sk_reset_timer(struct sock *sk, struct timer_list* timer,
1094 			   unsigned long expires);
1095 
1096 extern void sk_stop_timer(struct sock *sk, struct timer_list* timer);
1097 
1098 extern int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
1099 
1100 static inline int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb)
1101 {
1102 	/* Cast skb->rcvbuf to unsigned... It's pointless, but reduces
1103 	   number of warnings when compiling with -W --ANK
1104 	 */
1105 	if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >=
1106 	    (unsigned)sk->sk_rcvbuf)
1107 		return -ENOMEM;
1108 	skb_set_owner_r(skb, sk);
1109 	skb_queue_tail(&sk->sk_error_queue, skb);
1110 	if (!sock_flag(sk, SOCK_DEAD))
1111 		sk->sk_data_ready(sk, skb->len);
1112 	return 0;
1113 }
1114 
1115 /*
1116  *	Recover an error report and clear atomically
1117  */
1118 
1119 static inline int sock_error(struct sock *sk)
1120 {
1121 	int err;
1122 	if (likely(!sk->sk_err))
1123 		return 0;
1124 	err = xchg(&sk->sk_err, 0);
1125 	return -err;
1126 }
1127 
1128 static inline unsigned long sock_wspace(struct sock *sk)
1129 {
1130 	int amt = 0;
1131 
1132 	if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
1133 		amt = sk->sk_sndbuf - atomic_read(&sk->sk_wmem_alloc);
1134 		if (amt < 0)
1135 			amt = 0;
1136 	}
1137 	return amt;
1138 }
1139 
1140 static inline void sk_wake_async(struct sock *sk, int how, int band)
1141 {
1142 	if (sk->sk_socket && sk->sk_socket->fasync_list)
1143 		sock_wake_async(sk->sk_socket, how, band);
1144 }
1145 
1146 #define SOCK_MIN_SNDBUF 2048
1147 #define SOCK_MIN_RCVBUF 256
1148 
1149 static inline void sk_stream_moderate_sndbuf(struct sock *sk)
1150 {
1151 	if (!(sk->sk_userlocks & SOCK_SNDBUF_LOCK)) {
1152 		sk->sk_sndbuf = min(sk->sk_sndbuf, sk->sk_wmem_queued / 2);
1153 		sk->sk_sndbuf = max(sk->sk_sndbuf, SOCK_MIN_SNDBUF);
1154 	}
1155 }
1156 
1157 static inline struct sk_buff *sk_stream_alloc_pskb(struct sock *sk,
1158 						   int size, int mem,
1159 						   gfp_t gfp)
1160 {
1161 	struct sk_buff *skb;
1162 	int hdr_len;
1163 
1164 	hdr_len = SKB_DATA_ALIGN(sk->sk_prot->max_header);
1165 	skb = alloc_skb_fclone(size + hdr_len, gfp);
1166 	if (skb) {
1167 		skb->truesize += mem;
1168 		if (sk_stream_wmem_schedule(sk, skb->truesize)) {
1169 			skb_reserve(skb, hdr_len);
1170 			return skb;
1171 		}
1172 		__kfree_skb(skb);
1173 	} else {
1174 		sk->sk_prot->enter_memory_pressure();
1175 		sk_stream_moderate_sndbuf(sk);
1176 	}
1177 	return NULL;
1178 }
1179 
1180 static inline struct sk_buff *sk_stream_alloc_skb(struct sock *sk,
1181 						  int size,
1182 						  gfp_t gfp)
1183 {
1184 	return sk_stream_alloc_pskb(sk, size, 0, gfp);
1185 }
1186 
1187 static inline struct page *sk_stream_alloc_page(struct sock *sk)
1188 {
1189 	struct page *page = NULL;
1190 
1191 	page = alloc_pages(sk->sk_allocation, 0);
1192 	if (!page) {
1193 		sk->sk_prot->enter_memory_pressure();
1194 		sk_stream_moderate_sndbuf(sk);
1195 	}
1196 	return page;
1197 }
1198 
1199 #define sk_stream_for_retrans_queue(skb, sk)				\
1200 		for (skb = (sk)->sk_write_queue.next;			\
1201 		     (skb != (sk)->sk_send_head) &&			\
1202 		     (skb != (struct sk_buff *)&(sk)->sk_write_queue);	\
1203 		     skb = skb->next)
1204 
1205 /*from STCP for fast SACK Process*/
1206 #define sk_stream_for_retrans_queue_from(skb, sk)			\
1207 		for (; (skb != (sk)->sk_send_head) &&                   \
1208 		     (skb != (struct sk_buff *)&(sk)->sk_write_queue);	\
1209 		     skb = skb->next)
1210 
1211 /*
1212  *	Default write policy as shown to user space via poll/select/SIGIO
1213  */
1214 static inline int sock_writeable(const struct sock *sk)
1215 {
1216 	return atomic_read(&sk->sk_wmem_alloc) < (sk->sk_sndbuf / 2);
1217 }
1218 
1219 static inline gfp_t gfp_any(void)
1220 {
1221 	return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
1222 }
1223 
1224 static inline long sock_rcvtimeo(const struct sock *sk, int noblock)
1225 {
1226 	return noblock ? 0 : sk->sk_rcvtimeo;
1227 }
1228 
1229 static inline long sock_sndtimeo(const struct sock *sk, int noblock)
1230 {
1231 	return noblock ? 0 : sk->sk_sndtimeo;
1232 }
1233 
1234 static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
1235 {
1236 	return (waitall ? len : min_t(int, sk->sk_rcvlowat, len)) ? : 1;
1237 }
1238 
1239 /* Alas, with timeout socket operations are not restartable.
1240  * Compare this to poll().
1241  */
1242 static inline int sock_intr_errno(long timeo)
1243 {
1244 	return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
1245 }
1246 
1247 static __inline__ void
1248 sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
1249 {
1250 	struct timeval stamp;
1251 
1252 	skb_get_timestamp(skb, &stamp);
1253 	if (sock_flag(sk, SOCK_RCVTSTAMP)) {
1254 		/* Race occurred between timestamp enabling and packet
1255 		   receiving.  Fill in the current time for now. */
1256 		if (stamp.tv_sec == 0)
1257 			do_gettimeofday(&stamp);
1258 		skb_set_timestamp(skb, &stamp);
1259 		put_cmsg(msg, SOL_SOCKET, SO_TIMESTAMP, sizeof(struct timeval),
1260 			 &stamp);
1261 	} else
1262 		sk->sk_stamp = stamp;
1263 }
1264 
1265 /**
1266  * sk_eat_skb - Release a skb if it is no longer needed
1267  * @sk: socket to eat this skb from
1268  * @skb: socket buffer to eat
1269  *
1270  * This routine must be called with interrupts disabled or with the socket
1271  * locked so that the sk_buff queue operation is ok.
1272 */
1273 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb)
1274 {
1275 	__skb_unlink(skb, &sk->sk_receive_queue);
1276 	__kfree_skb(skb);
1277 }
1278 
1279 extern void sock_enable_timestamp(struct sock *sk);
1280 extern int sock_get_timestamp(struct sock *, struct timeval __user *);
1281 
1282 /*
1283  *	Enable debug/info messages
1284  */
1285 
1286 #ifdef CONFIG_NETDEBUG
1287 #define NETDEBUG(fmt, args...)	printk(fmt,##args)
1288 #define LIMIT_NETDEBUG(fmt, args...) do { if (net_ratelimit()) printk(fmt,##args); } while(0)
1289 #else
1290 #define NETDEBUG(fmt, args...)	do { } while (0)
1291 #define LIMIT_NETDEBUG(fmt, args...) do { } while(0)
1292 #endif
1293 
1294 /*
1295  * Macros for sleeping on a socket. Use them like this:
1296  *
1297  * SOCK_SLEEP_PRE(sk)
1298  * if (condition)
1299  * 	schedule();
1300  * SOCK_SLEEP_POST(sk)
1301  *
1302  * N.B. These are now obsolete and were, afaik, only ever used in DECnet
1303  * and when the last use of them in DECnet has gone, I'm intending to
1304  * remove them.
1305  */
1306 
1307 #define SOCK_SLEEP_PRE(sk) 	{ struct task_struct *tsk = current; \
1308 				DECLARE_WAITQUEUE(wait, tsk); \
1309 				tsk->state = TASK_INTERRUPTIBLE; \
1310 				add_wait_queue((sk)->sk_sleep, &wait); \
1311 				release_sock(sk);
1312 
1313 #define SOCK_SLEEP_POST(sk)	tsk->state = TASK_RUNNING; \
1314 				remove_wait_queue((sk)->sk_sleep, &wait); \
1315 				lock_sock(sk); \
1316 				}
1317 
1318 static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool)
1319 {
1320 	if (valbool)
1321 		sock_set_flag(sk, bit);
1322 	else
1323 		sock_reset_flag(sk, bit);
1324 }
1325 
1326 extern __u32 sysctl_wmem_max;
1327 extern __u32 sysctl_rmem_max;
1328 
1329 #ifdef CONFIG_NET
1330 int siocdevprivate_ioctl(unsigned int fd, unsigned int cmd, unsigned long arg);
1331 #else
1332 static inline int siocdevprivate_ioctl(unsigned int fd, unsigned int cmd, unsigned long arg)
1333 {
1334 	return -ENODEV;
1335 }
1336 #endif
1337 
1338 extern void sk_init(void);
1339 
1340 #ifdef CONFIG_SYSCTL
1341 extern struct ctl_table core_table[];
1342 #endif
1343 
1344 extern int sysctl_optmem_max;
1345 
1346 extern __u32 sysctl_wmem_default;
1347 extern __u32 sysctl_rmem_default;
1348 
1349 #endif	/* _SOCK_H */
1350