sock.h 49.4 KB
Newer Older
Linus Torvalds's avatar
Linus Torvalds committed
1 2 3 4 5 6 7 8 9
/*
 * INET		An implementation of the TCP/IP protocol suite for the LINUX
 *		operating system.  INET is implemented using the  BSD Socket
 *		interface as the means of communication with the user level.
 *
 *		Definitions for the AF_INET socket handler.
 *
 * Version:	@(#)sock.h	1.0.4	05/13/93
 *
10
 * Authors:	Ross Biro
Linus Torvalds's avatar
Linus Torvalds committed
11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42
 *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
 *		Corey Minyard <wf-rch!minyard@relay.EU.net>
 *		Florian La Roche <flla@stud.uni-sb.de>
 *
 * Fixes:
 *		Alan Cox	:	Volatiles in skbuff pointers. See
 *					skbuff comments. May be overdone,
 *					better to prove they can be removed
 *					than the reverse.
 *		Alan Cox	:	Added a zapped field for tcp to note
 *					a socket is reset and must stay shut up
 *		Alan Cox	:	New fields for options
 *	Pauline Middelink	:	identd support
 *		Alan Cox	:	Eliminate low level recv/recvfrom
 *		David S. Miller	:	New socket lookup architecture.
 *              Steve Whitehouse:       Default routines for sock_ops
 *              Arnaldo C. Melo :	removed net_pinfo, tp_pinfo and made
 *              			protinfo be just a void pointer, as the
 *              			protocol specific parts were moved to
 *              			respective headers and ipv4/v6, etc now
 *              			use private slabcaches for its socks
 *              Pedro Hortas	:	New flags field for socket options
 *
 *
 *		This program is free software; you can redistribute it and/or
 *		modify it under the terms of the GNU General Public License
 *		as published by the Free Software Foundation; either version
 *		2 of the License, or (at your option) any later version.
 */
#ifndef _SOCK_H
#define _SOCK_H

43
#include <linux/kernel.h>
Linus Torvalds's avatar
Linus Torvalds committed
44
#include <linux/list.h>
45
#include <linux/list_nulls.h>
Linus Torvalds's avatar
Linus Torvalds committed
46 47 48
#include <linux/timer.h>
#include <linux/cache.h>
#include <linux/module.h>
49
#include <linux/lockdep.h>
Linus Torvalds's avatar
Linus Torvalds committed
50 51
#include <linux/netdevice.h>
#include <linux/skbuff.h>	/* struct sk_buff */
Al Viro's avatar
Al Viro committed
52
#include <linux/mm.h>
Linus Torvalds's avatar
Linus Torvalds committed
53
#include <linux/security.h>
54
#include <linux/slab.h>
Linus Torvalds's avatar
Linus Torvalds committed
55 56

#include <linux/filter.h>
57
#include <linux/rculist_nulls.h>
58
#include <linux/poll.h>
Linus Torvalds's avatar
Linus Torvalds committed
59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75

#include <asm/atomic.h>
#include <net/dst.h>
#include <net/checksum.h>

/*
 * This structure really needs to be cleaned up.
 * Most of it is for TCP, and not used by any of
 * the other protocols.
 */

/* Define this to get the SOCK_DBG debugging facility. */
#define SOCK_DEBUGGING
#ifdef SOCK_DEBUGGING
#define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \
					printk(KERN_DEBUG msg); } while (0)
#else
76
/* Validate arguments and do nothing */
77
static inline void __attribute__ ((format (printf, 2, 3)))
78 79 80
SOCK_DEBUG(struct sock *sk, const char *msg, ...)
{
}
Linus Torvalds's avatar
Linus Torvalds committed
81 82 83 84 85 86 87 88
#endif

/* This is the per-socket lock.  The spinlock provides a synchronization
 * between user contexts and software interrupt processing, whereas the
 * mini-semaphore synchronizes multiple users amongst themselves.
 */
typedef struct {
	spinlock_t		slock;
89
	int			owned;
Linus Torvalds's avatar
Linus Torvalds committed
90
	wait_queue_head_t	wq;
91 92 93 94 95 96 97 98 99
	/*
	 * We express the mutex-alike socket_lock semantics
	 * to the lock validator by explicitly managing
	 * the slock as a lock variant (in addition to
	 * the slock itself):
	 */
#ifdef CONFIG_DEBUG_LOCK_ALLOC
	struct lockdep_map dep_map;
#endif
Linus Torvalds's avatar
Linus Torvalds committed
100 101 102
} socket_lock_t;

struct sock;
103
struct proto;
104
struct net;
Linus Torvalds's avatar
Linus Torvalds committed
105 106

/**
107
 *	struct sock_common - minimal network layer representation of sockets
Eric Dumazet's avatar
Eric Dumazet committed
108
 *	@skc_node: main hash linkage for various protocol lookup tables
109
 *	@skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol
Eric Dumazet's avatar
Eric Dumazet committed
110
 *	@skc_refcnt: reference count
111
 *	@skc_tx_queue_mapping: tx queue number for this connection
Eric Dumazet's avatar
Eric Dumazet committed
112
 *	@skc_hash: hash value used with various protocol lookup tables
113
 *	@skc_u16hashes: two u16 hash values used by UDP lookup tables
114 115 116 117 118
 *	@skc_family: network address family
 *	@skc_state: Connection state
 *	@skc_reuse: %SO_REUSEADDR setting
 *	@skc_bound_dev_if: bound device index if != 0
 *	@skc_bind_node: bind hash linkage for various protocol lookup tables
119
 *	@skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol
120
 *	@skc_prot: protocol handlers inside a network family
121
 *	@skc_net: reference to the network namespace of this socket
122 123
 *
 *	This is the minimal network layer representation of sockets, the header
124 125
 *	for struct sock and struct inet_timewait_sock.
 */
Linus Torvalds's avatar
Linus Torvalds committed
126
struct sock_common {
Eric Dumazet's avatar
Eric Dumazet committed
127 128 129
	/*
	 * first fields are not copied in sock_copy()
	 */
130 131 132 133
	union {
		struct hlist_node	skc_node;
		struct hlist_nulls_node skc_nulls_node;
	};
Linus Torvalds's avatar
Linus Torvalds committed
134
	atomic_t		skc_refcnt;
135
	int			skc_tx_queue_mapping;
Eric Dumazet's avatar
Eric Dumazet committed
136

137 138 139 140
	union  {
		unsigned int	skc_hash;
		__u16		skc_u16hashes[2];
	};
Eric Dumazet's avatar
Eric Dumazet committed
141 142 143 144
	unsigned short		skc_family;
	volatile unsigned char	skc_state;
	unsigned char		skc_reuse;
	int			skc_bound_dev_if;
145 146 147 148
	union {
		struct hlist_node	skc_bind_node;
		struct hlist_nulls_node skc_portaddr_node;
	};
149
	struct proto		*skc_prot;
150
#ifdef CONFIG_NET_NS
151
	struct net	 	*skc_net;
152
#endif
Linus Torvalds's avatar
Linus Torvalds committed
153 154 155 156
};

/**
  *	struct sock - network layer representation of sockets
157
  *	@__sk_common: shared layout with inet_timewait_sock
158 159 160 161
  *	@sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
  *	@sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
  *	@sk_lock:	synchronizer
  *	@sk_rcvbuf: size of receive buffer in bytes
162
  *	@sk_wq: sock wait queue and async head
163 164 165 166 167 168 169
  *	@sk_dst_cache: destination cache
  *	@sk_dst_lock: destination cache lock
  *	@sk_policy: flow policy
  *	@sk_rmem_alloc: receive queue bytes committed
  *	@sk_receive_queue: incoming packets
  *	@sk_wmem_alloc: transmit queue bytes committed
  *	@sk_write_queue: Packet sending queue
170
  *	@sk_async_wait_queue: DMA copied packets
171 172 173 174 175
  *	@sk_omem_alloc: "o" is "option" or "other"
  *	@sk_wmem_queued: persistent queue size
  *	@sk_forward_alloc: space allocated forward
  *	@sk_allocation: allocation mode
  *	@sk_sndbuf: size of send buffer in bytes
Wang Chen's avatar
Wang Chen committed
176
  *	@sk_flags: %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE,
177
  *		   %SO_OOBINLINE settings, %SO_TIMESTAMPING settings
178 179
  *	@sk_no_check: %SO_NO_CHECK setting, wether or not checkup packets
  *	@sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
180
  *	@sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
181
  *	@sk_gso_max_size: Maximum GSO segment size to build
182 183 184 185
  *	@sk_lingertime: %SO_LINGER l_linger setting
  *	@sk_backlog: always used with the per-socket spinlock held
  *	@sk_callback_lock: used with the callbacks in the end of this struct
  *	@sk_error_queue: rarely used
Wang Chen's avatar
Wang Chen committed
186 187
  *	@sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt,
  *			  IPV6_ADDRFORM for instance)
188
  *	@sk_err: last error
Wang Chen's avatar
Wang Chen committed
189 190
  *	@sk_err_soft: errors that don't cause failure but are the cause of a
  *		      persistent failure not just 'timed out'
Eric Dumazet's avatar
Eric Dumazet committed
191
  *	@sk_drops: raw/udp drops counter
192 193 194 195 196 197 198 199 200
  *	@sk_ack_backlog: current listen backlog
  *	@sk_max_ack_backlog: listen backlog set in listen()
  *	@sk_priority: %SO_PRIORITY setting
  *	@sk_type: socket type (%SOCK_STREAM, etc)
  *	@sk_protocol: which protocol this socket belongs in this network family
  *	@sk_peercred: %SO_PEERCRED setting
  *	@sk_rcvlowat: %SO_RCVLOWAT setting
  *	@sk_rcvtimeo: %SO_RCVTIMEO setting
  *	@sk_sndtimeo: %SO_SNDTIMEO setting
201
  *	@sk_rxhash: flow hash received from netif layer
202 203 204 205 206 207 208 209 210
  *	@sk_filter: socket filtering instructions
  *	@sk_protinfo: private area, net family specific, when not using slab
  *	@sk_timer: sock cleanup timer
  *	@sk_stamp: time stamp of last packet received
  *	@sk_socket: Identd and reporting IO signals
  *	@sk_user_data: RPC layer private data
  *	@sk_sndmsg_page: cached page for sendmsg
  *	@sk_sndmsg_off: cached offset for sendmsg
  *	@sk_send_head: front of stuff to transmit
211
  *	@sk_security: used by security modules
212
  *	@sk_mark: generic packet mark
213 214 215 216 217 218 219
  *	@sk_write_pending: a write to stream socket waits to start
  *	@sk_state_change: callback to indicate change in the state of the sock
  *	@sk_data_ready: callback to indicate there is data to be processed
  *	@sk_write_space: callback to indicate there is bf sending space available
  *	@sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
  *	@sk_backlog_rcv: callback to process the backlog
  *	@sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
Linus Torvalds's avatar
Linus Torvalds committed
220 221 222
 */
struct sock {
	/*
223
	 * Now struct inet_timewait_sock also uses sock_common, so please just
Linus Torvalds's avatar
Linus Torvalds committed
224 225 226
	 * don't add nothing before this first member (__sk_common) --acme
	 */
	struct sock_common	__sk_common;
Eric Dumazet's avatar
Eric Dumazet committed
227 228 229
#define sk_node			__sk_common.skc_node
#define sk_nulls_node		__sk_common.skc_nulls_node
#define sk_refcnt		__sk_common.skc_refcnt
230
#define sk_tx_queue_mapping	__sk_common.skc_tx_queue_mapping
Eric Dumazet's avatar
Eric Dumazet committed
231 232 233

#define sk_copy_start		__sk_common.skc_hash
#define sk_hash			__sk_common.skc_hash
Linus Torvalds's avatar
Linus Torvalds committed
234 235 236 237 238
#define sk_family		__sk_common.skc_family
#define sk_state		__sk_common.skc_state
#define sk_reuse		__sk_common.skc_reuse
#define sk_bound_dev_if		__sk_common.skc_bound_dev_if
#define sk_bind_node		__sk_common.skc_bind_node
239
#define sk_prot			__sk_common.skc_prot
240
#define sk_net			__sk_common.skc_net
241
	kmemcheck_bitfield_begin(flags);
242 243 244 245 246
	unsigned int		sk_shutdown  : 2,
				sk_no_check  : 2,
				sk_userlocks : 4,
				sk_protocol  : 8,
				sk_type      : 16;
247
	kmemcheck_bitfield_end(flags);
Linus Torvalds's avatar
Linus Torvalds committed
248 249
	int			sk_rcvbuf;
	socket_lock_t		sk_lock;
250 251 252 253 254 255 256 257
	/*
	 * The backlog queue is special, it is always used with
	 * the per-socket spinlock held and requires low latency
	 * access. Therefore we special case it's implementation.
	 */
	struct {
		struct sk_buff *head;
		struct sk_buff *tail;
Zhu Yi's avatar
Zhu Yi committed
258
		int len;
259
	} sk_backlog;
260
	struct socket_wq	*sk_wq;
Linus Torvalds's avatar
Linus Torvalds committed
261
	struct dst_entry	*sk_dst_cache;
262
#ifdef CONFIG_XFRM
Linus Torvalds's avatar
Linus Torvalds committed
263
	struct xfrm_policy	*sk_policy[2];
264
#endif
Eric Dumazet's avatar
Eric Dumazet committed
265
	spinlock_t		sk_dst_lock;
Linus Torvalds's avatar
Linus Torvalds committed
266 267 268
	atomic_t		sk_rmem_alloc;
	atomic_t		sk_wmem_alloc;
	atomic_t		sk_omem_alloc;
269
	int			sk_sndbuf;
Linus Torvalds's avatar
Linus Torvalds committed
270 271
	struct sk_buff_head	sk_receive_queue;
	struct sk_buff_head	sk_write_queue;
272
#ifdef CONFIG_NET_DMA
273
	struct sk_buff_head	sk_async_wait_queue;
274
#endif
Linus Torvalds's avatar
Linus Torvalds committed
275 276
	int			sk_wmem_queued;
	int			sk_forward_alloc;
Al Viro's avatar
Al Viro committed
277
	gfp_t			sk_allocation;
Linus Torvalds's avatar
Linus Torvalds committed
278
	int			sk_route_caps;
279
	int			sk_gso_type;
280
	unsigned int		sk_gso_max_size;
281
	int			sk_rcvlowat;
282 283 284
#ifdef CONFIG_RPS
	__u32			sk_rxhash;
#endif
Linus Torvalds's avatar
Linus Torvalds committed
285 286 287
	unsigned long 		sk_flags;
	unsigned long	        sk_lingertime;
	struct sk_buff_head	sk_error_queue;
288
	struct proto		*sk_prot_creator;
Linus Torvalds's avatar
Linus Torvalds committed
289 290 291
	rwlock_t		sk_callback_lock;
	int			sk_err,
				sk_err_soft;
Wang Chen's avatar
Wang Chen committed
292
	atomic_t		sk_drops;
Linus Torvalds's avatar
Linus Torvalds committed
293 294 295 296 297 298 299 300 301
	unsigned short		sk_ack_backlog;
	unsigned short		sk_max_ack_backlog;
	__u32			sk_priority;
	struct ucred		sk_peercred;
	long			sk_rcvtimeo;
	long			sk_sndtimeo;
	struct sk_filter      	*sk_filter;
	void			*sk_protinfo;
	struct timer_list	sk_timer;
302
	ktime_t			sk_stamp;
Linus Torvalds's avatar
Linus Torvalds committed
303 304 305 306 307 308
	struct socket		*sk_socket;
	void			*sk_user_data;
	struct page		*sk_sndmsg_page;
	struct sk_buff		*sk_send_head;
	__u32			sk_sndmsg_off;
	int			sk_write_pending;
Alexey Dobriyan's avatar
Alexey Dobriyan committed
309
#ifdef CONFIG_SECURITY
Linus Torvalds's avatar
Linus Torvalds committed
310
	void			*sk_security;
Alexey Dobriyan's avatar
Alexey Dobriyan committed
311
#endif
312 313
	__u32			sk_mark;
	/* XXX 4 bytes hole on 64 bit */
Linus Torvalds's avatar
Linus Torvalds committed
314 315 316 317 318 319 320 321 322 323 324 325
	void			(*sk_state_change)(struct sock *sk);
	void			(*sk_data_ready)(struct sock *sk, int bytes);
	void			(*sk_write_space)(struct sock *sk);
	void			(*sk_error_report)(struct sock *sk);
  	int			(*sk_backlog_rcv)(struct sock *sk,
						  struct sk_buff *skb);  
	void                    (*sk_destruct)(struct sock *sk);
};

/*
 * Hashed lists helper routines
 */
Li Zefan's avatar
Li Zefan committed
326 327 328 329 330
static inline struct sock *sk_entry(const struct hlist_node *node)
{
	return hlist_entry(node, struct sock, sk_node);
}

331
static inline struct sock *__sk_head(const struct hlist_head *head)
Linus Torvalds's avatar
Linus Torvalds committed
332 333 334 335
{
	return hlist_entry(head->first, struct sock, sk_node);
}

336
static inline struct sock *sk_head(const struct hlist_head *head)
Linus Torvalds's avatar
Linus Torvalds committed
337 338 339 340
{
	return hlist_empty(head) ? NULL : __sk_head(head);
}

341 342 343 344 345 346 347 348 349 350
static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head)
{
	return hlist_nulls_entry(head->first, struct sock, sk_nulls_node);
}

static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head)
{
	return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head);
}

351
static inline struct sock *sk_next(const struct sock *sk)
Linus Torvalds's avatar
Linus Torvalds committed
352 353 354 355 356
{
	return sk->sk_node.next ?
		hlist_entry(sk->sk_node.next, struct sock, sk_node) : NULL;
}

357 358 359 360 361 362 363 364
static inline struct sock *sk_nulls_next(const struct sock *sk)
{
	return (!is_a_nulls(sk->sk_nulls_node.next)) ?
		hlist_nulls_entry(sk->sk_nulls_node.next,
				  struct sock, sk_nulls_node) :
		NULL;
}

365
static inline int sk_unhashed(const struct sock *sk)
Linus Torvalds's avatar
Linus Torvalds committed
366 367 368 369
{
	return hlist_unhashed(&sk->sk_node);
}

370
static inline int sk_hashed(const struct sock *sk)
Linus Torvalds's avatar
Linus Torvalds committed
371
{
Akinobu Mita's avatar
Akinobu Mita committed
372
	return !sk_unhashed(sk);
Linus Torvalds's avatar
Linus Torvalds committed
373 374 375 376 377 378 379
}

static __inline__ void sk_node_init(struct hlist_node *node)
{
	node->pprev = NULL;
}

380 381 382 383 384
static __inline__ void sk_nulls_node_init(struct hlist_nulls_node *node)
{
	node->pprev = NULL;
}

Linus Torvalds's avatar
Linus Torvalds committed
385 386 387 388 389
static __inline__ void __sk_del_node(struct sock *sk)
{
	__hlist_del(&sk->sk_node);
}

390
/* NB: equivalent to hlist_del_init_rcu */
Linus Torvalds's avatar
Linus Torvalds committed
391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430
static __inline__ int __sk_del_node_init(struct sock *sk)
{
	if (sk_hashed(sk)) {
		__sk_del_node(sk);
		sk_node_init(&sk->sk_node);
		return 1;
	}
	return 0;
}

/* Grab socket reference count. This operation is valid only
   when sk is ALREADY grabbed f.e. it is found in hash table
   or a list and the lookup is made under lock preventing hash table
   modifications.
 */

static inline void sock_hold(struct sock *sk)
{
	atomic_inc(&sk->sk_refcnt);
}

/* Ungrab socket in the context, which assumes that socket refcnt
   cannot hit zero, f.e. it is true in context of any socketcall.
 */
static inline void __sock_put(struct sock *sk)
{
	atomic_dec(&sk->sk_refcnt);
}

static __inline__ int sk_del_node_init(struct sock *sk)
{
	int rc = __sk_del_node_init(sk);

	if (rc) {
		/* paranoid for a while -acme */
		WARN_ON(atomic_read(&sk->sk_refcnt) == 1);
		__sock_put(sk);
	}
	return rc;
}
431
#define sk_del_node_init_rcu(sk)	sk_del_node_init(sk)
Linus Torvalds's avatar
Linus Torvalds committed
432

433
static __inline__ int __sk_nulls_del_node_init_rcu(struct sock *sk)
434 435
{
	if (sk_hashed(sk)) {
436
		hlist_nulls_del_init_rcu(&sk->sk_nulls_node);
437 438 439 440 441
		return 1;
	}
	return 0;
}

442
static __inline__ int sk_nulls_del_node_init_rcu(struct sock *sk)
443
{
444
	int rc = __sk_nulls_del_node_init_rcu(sk);
445 446 447 448 449 450 451 452 453

	if (rc) {
		/* paranoid for a while -acme */
		WARN_ON(atomic_read(&sk->sk_refcnt) == 1);
		__sock_put(sk);
	}
	return rc;
}

Linus Torvalds's avatar
Linus Torvalds committed
454 455 456 457 458 459 460 461 462 463 464
static __inline__ void __sk_add_node(struct sock *sk, struct hlist_head *list)
{
	hlist_add_head(&sk->sk_node, list);
}

static __inline__ void sk_add_node(struct sock *sk, struct hlist_head *list)
{
	sock_hold(sk);
	__sk_add_node(sk, list);
}

465 466 467 468 469 470
static __inline__ void sk_add_node_rcu(struct sock *sk, struct hlist_head *list)
{
	sock_hold(sk);
	hlist_add_head_rcu(&sk->sk_node, list);
}

471
static __inline__ void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
472
{
473
	hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list);
474 475
}

476
static __inline__ void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
477 478
{
	sock_hold(sk);
479
	__sk_nulls_add_node_rcu(sk, list);
480 481
}

Linus Torvalds's avatar
Linus Torvalds committed
482 483 484 485 486 487 488 489 490 491 492 493 494
static __inline__ void __sk_del_bind_node(struct sock *sk)
{
	__hlist_del(&sk->sk_bind_node);
}

static __inline__ void sk_add_bind_node(struct sock *sk,
					struct hlist_head *list)
{
	hlist_add_head(&sk->sk_bind_node, list);
}

#define sk_for_each(__sk, node, list) \
	hlist_for_each_entry(__sk, node, list, sk_node)
495 496
#define sk_for_each_rcu(__sk, node, list) \
	hlist_for_each_entry_rcu(__sk, node, list, sk_node)
497 498 499 500
#define sk_nulls_for_each(__sk, node, list) \
	hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)
#define sk_nulls_for_each_rcu(__sk, node, list) \
	hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)
Linus Torvalds's avatar
Linus Torvalds committed
501 502 503
#define sk_for_each_from(__sk, node) \
	if (__sk && ({ node = &(__sk)->sk_node; 1; })) \
		hlist_for_each_entry_from(__sk, node, sk_node)
504 505 506
#define sk_nulls_for_each_from(__sk, node) \
	if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \
		hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node)
Linus Torvalds's avatar
Linus Torvalds committed
507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528
#define sk_for_each_continue(__sk, node) \
	if (__sk && ({ node = &(__sk)->sk_node; 1; })) \
		hlist_for_each_entry_continue(__sk, node, sk_node)
#define sk_for_each_safe(__sk, node, tmp, list) \
	hlist_for_each_entry_safe(__sk, node, tmp, list, sk_node)
#define sk_for_each_bound(__sk, node, list) \
	hlist_for_each_entry(__sk, node, list, sk_bind_node)

/* Sock flags */
enum sock_flags {
	SOCK_DEAD,
	SOCK_DONE,
	SOCK_URGINLINE,
	SOCK_KEEPOPEN,
	SOCK_LINGER,
	SOCK_DESTROY,
	SOCK_BROADCAST,
	SOCK_TIMESTAMP,
	SOCK_ZAPPED,
	SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */
	SOCK_DBG, /* %SO_DEBUG setting */
	SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
529
	SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */
Linus Torvalds's avatar
Linus Torvalds committed
530 531
	SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
	SOCK_QUEUE_SHRUNK, /* write queue has been shrunk recently */
532 533 534 535 536 537 538
	SOCK_TIMESTAMPING_TX_HARDWARE,  /* %SOF_TIMESTAMPING_TX_HARDWARE */
	SOCK_TIMESTAMPING_TX_SOFTWARE,  /* %SOF_TIMESTAMPING_TX_SOFTWARE */
	SOCK_TIMESTAMPING_RX_HARDWARE,  /* %SOF_TIMESTAMPING_RX_HARDWARE */
	SOCK_TIMESTAMPING_RX_SOFTWARE,  /* %SOF_TIMESTAMPING_RX_SOFTWARE */
	SOCK_TIMESTAMPING_SOFTWARE,     /* %SOF_TIMESTAMPING_SOFTWARE */
	SOCK_TIMESTAMPING_RAW_HARDWARE, /* %SOF_TIMESTAMPING_RAW_HARDWARE */
	SOCK_TIMESTAMPING_SYS_HARDWARE, /* %SOF_TIMESTAMPING_SYS_HARDWARE */
Eric Dumazet's avatar
Eric Dumazet committed
539
	SOCK_FASYNC, /* fasync() active */
540
	SOCK_RXQ_OVFL,
Linus Torvalds's avatar
Linus Torvalds committed
541 542
};

Ralf Baechle's avatar
Ralf Baechle committed
543 544 545 546 547
static inline void sock_copy_flags(struct sock *nsk, struct sock *osk)
{
	nsk->sk_flags = osk->sk_flags;
}

Linus Torvalds's avatar
Linus Torvalds committed
548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574
static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
{
	__set_bit(flag, &sk->sk_flags);
}

static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag)
{
	__clear_bit(flag, &sk->sk_flags);
}

static inline int sock_flag(struct sock *sk, enum sock_flags flag)
{
	return test_bit(flag, &sk->sk_flags);
}

static inline void sk_acceptq_removed(struct sock *sk)
{
	sk->sk_ack_backlog--;
}

static inline void sk_acceptq_added(struct sock *sk)
{
	sk->sk_ack_backlog++;
}

static inline int sk_acceptq_is_full(struct sock *sk)
{
575
	return sk->sk_ack_backlog > sk->sk_max_ack_backlog;
Linus Torvalds's avatar
Linus Torvalds committed
576 577 578 579 580 581 582
}

/*
 * Compute minimal free write space needed to queue new packets.
 */
static inline int sk_stream_min_wspace(struct sock *sk)
{
583
	return sk->sk_wmem_queued >> 1;
Linus Torvalds's avatar
Linus Torvalds committed
584 585 586 587 588 589 590 591 592 593 594 595 596 597
}

static inline int sk_stream_wspace(struct sock *sk)
{
	return sk->sk_sndbuf - sk->sk_wmem_queued;
}

extern void sk_stream_write_space(struct sock *sk);

static inline int sk_stream_memory_free(struct sock *sk)
{
	return sk->sk_wmem_queued < sk->sk_sndbuf;
}

Zhu Yi's avatar
Zhu Yi committed
598
/* OOB backlog add */
Zhu Yi's avatar
Zhu Yi committed
599
static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
600 601 602 603 604 605 606 607 608
{
	if (!sk->sk_backlog.tail) {
		sk->sk_backlog.head = sk->sk_backlog.tail = skb;
	} else {
		sk->sk_backlog.tail->next = skb;
		sk->sk_backlog.tail = skb;
	}
	skb->next = NULL;
}
Linus Torvalds's avatar
Linus Torvalds committed
609

610 611 612 613 614 615 616 617 618 619
/*
 * Take into account size of receive queue and backlog queue
 */
static inline bool sk_rcvqueues_full(const struct sock *sk, const struct sk_buff *skb)
{
	unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc);

	return qsize + skb->truesize > sk->sk_rcvbuf;
}

Zhu Yi's avatar
Zhu Yi committed
620
/* The per-socket spinlock must be held here. */
621
static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb)
Zhu Yi's avatar
Zhu Yi committed
622
{
623
	if (sk_rcvqueues_full(sk, skb))
Zhu Yi's avatar
Zhu Yi committed
624 625
		return -ENOBUFS;

Zhu Yi's avatar
Zhu Yi committed
626
	__sk_add_backlog(sk, skb);
Zhu Yi's avatar
Zhu Yi committed
627 628 629 630
	sk->sk_backlog.len += skb->truesize;
	return 0;
}

631 632 633 634 635
static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
{
	return sk->sk_backlog_rcv(sk, skb);
}

636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669
static inline void sock_rps_record_flow(const struct sock *sk)
{
#ifdef CONFIG_RPS
	struct rps_sock_flow_table *sock_flow_table;

	rcu_read_lock();
	sock_flow_table = rcu_dereference(rps_sock_flow_table);
	rps_record_sock_flow(sock_flow_table, sk->sk_rxhash);
	rcu_read_unlock();
#endif
}

static inline void sock_rps_reset_flow(const struct sock *sk)
{
#ifdef CONFIG_RPS
	struct rps_sock_flow_table *sock_flow_table;

	rcu_read_lock();
	sock_flow_table = rcu_dereference(rps_sock_flow_table);
	rps_reset_sock_flow(sock_flow_table, sk->sk_rxhash);
	rcu_read_unlock();
#endif
}

static inline void sock_rps_save_rxhash(struct sock *sk, u32 rxhash)
{
#ifdef CONFIG_RPS
	if (unlikely(sk->sk_rxhash != rxhash)) {
		sock_rps_reset_flow(sk);
		sk->sk_rxhash = rxhash;
	}
#endif
}

670 671 672 673 674 675 676 677 678 679 680
#define sk_wait_event(__sk, __timeo, __condition)			\
	({	int __rc;						\
		release_sock(__sk);					\
		__rc = __condition;					\
		if (!__rc) {						\
			*(__timeo) = schedule_timeout(*(__timeo));	\
		}							\
		lock_sock(__sk);					\
		__rc = __condition;					\
		__rc;							\
	})
Linus Torvalds's avatar
Linus Torvalds committed
681 682 683 684 685 686 687 688 689

extern int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
extern int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
extern void sk_stream_wait_close(struct sock *sk, long timeo_p);
extern int sk_stream_error(struct sock *sk, int flags, int err);
extern void sk_stream_kill_queues(struct sock *sk);

extern int sk_wait_data(struct sock *sk, long *timeo);

690
struct request_sock_ops;
691
struct timewait_sock_ops;
692
struct inet_hashinfo;
693
struct raw_hashinfo;
694

Linus Torvalds's avatar
Linus Torvalds committed
695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711
/* Networking protocol blocks we attach to sockets.
 * socket layer -> transport layer interface
 * transport -> network interface is defined by struct inet_proto
 */
struct proto {
	void			(*close)(struct sock *sk, 
					long timeout);
	int			(*connect)(struct sock *sk,
				        struct sockaddr *uaddr, 
					int addr_len);
	int			(*disconnect)(struct sock *sk, int flags);

	struct sock *		(*accept) (struct sock *sk, int flags, int *err);

	int			(*ioctl)(struct sock *sk, int cmd,
					 unsigned long arg);
	int			(*init)(struct sock *sk);
712
	void			(*destroy)(struct sock *sk);
Linus Torvalds's avatar
Linus Torvalds committed
713 714 715
	void			(*shutdown)(struct sock *sk, int how);
	int			(*setsockopt)(struct sock *sk, int level, 
					int optname, char __user *optval,
716
					unsigned int optlen);
Linus Torvalds's avatar
Linus Torvalds committed
717 718 719
	int			(*getsockopt)(struct sock *sk, int level, 
					int optname, char __user *optval, 
					int __user *option);  	 
720
#ifdef CONFIG_COMPAT
721 722 723
	int			(*compat_setsockopt)(struct sock *sk,
					int level,
					int optname, char __user *optval,
724
					unsigned int optlen);
725 726 727 728
	int			(*compat_getsockopt)(struct sock *sk,
					int level,
					int optname, char __user *optval,
					int __user *option);
729
#endif
Linus Torvalds's avatar
Linus Torvalds committed
730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748
	int			(*sendmsg)(struct kiocb *iocb, struct sock *sk,
					   struct msghdr *msg, size_t len);
	int			(*recvmsg)(struct kiocb *iocb, struct sock *sk,
					   struct msghdr *msg,
					size_t len, int noblock, int flags, 
					int *addr_len);
	int			(*sendpage)(struct sock *sk, struct page *page,
					int offset, size_t size, int flags);
	int			(*bind)(struct sock *sk, 
					struct sockaddr *uaddr, int addr_len);

	int			(*backlog_rcv) (struct sock *sk, 
						struct sk_buff *skb);

	/* Keeping track of sk's, looking them up, and port selection methods. */
	void			(*hash)(struct sock *sk);
	void			(*unhash)(struct sock *sk);
	int			(*get_port)(struct sock *sk, unsigned short snum);

749
	/* Keeping track of sockets in use */
750
#ifdef CONFIG_PROC_FS
751
	unsigned int		inuse_idx;
752
#endif
753

Linus Torvalds's avatar
Linus Torvalds committed
754
	/* Memory pressure */
755
	void			(*enter_memory_pressure)(struct sock *sk);
Linus Torvalds's avatar
Linus Torvalds committed
756
	atomic_t		*memory_allocated;	/* Current allocated memory. */
757
	struct percpu_counter	*sockets_allocated;	/* Current number of sockets. */
Linus Torvalds's avatar
Linus Torvalds committed
758 759 760
	/*
	 * Pressure flag: try to collapse.
	 * Technical note: it is used by multiple contexts non atomically.
761
	 * All the __sk_mem_schedule() is of this nature: accounting
Linus Torvalds's avatar
Linus Torvalds committed
762 763 764 765 766 767 768 769
	 * is strict, actions are advisory and have some latency.
	 */
	int			*memory_pressure;
	int			*sysctl_mem;
	int			*sysctl_wmem;
	int			*sysctl_rmem;
	int			max_header;

770
	struct kmem_cache	*slab;
Linus Torvalds's avatar
Linus Torvalds committed
771
	unsigned int		obj_size;
772
	int			slab_flags;
Linus Torvalds's avatar
Linus Torvalds committed
773

774
	struct percpu_counter	*orphan_count;
775

776
	struct request_sock_ops	*rsk_prot;
777
	struct timewait_sock_ops *twsk_prot;
778

779 780
	union {
		struct inet_hashinfo	*hashinfo;
781
		struct udp_table	*udp_table;
782
		struct raw_hashinfo	*raw_hash;
783
	} h;
784

Linus Torvalds's avatar
Linus Torvalds committed
785 786 787 788 789
	struct module		*owner;

	char			name[32];

	struct list_head	node;
790 791 792
#ifdef SOCK_REFCNT_DEBUG
	atomic_t		socks;
#endif
Linus Torvalds's avatar
Linus Torvalds committed
793 794 795 796 797
};

extern int proto_register(struct proto *prot, int alloc_slab);
extern void proto_unregister(struct proto *prot);

798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822
#ifdef SOCK_REFCNT_DEBUG
static inline void sk_refcnt_debug_inc(struct sock *sk)
{
	atomic_inc(&sk->sk_prot->socks);
}

static inline void sk_refcnt_debug_dec(struct sock *sk)
{
	atomic_dec(&sk->sk_prot->socks);
	printk(KERN_DEBUG "%s socket %p released, %d are still alive\n",
	       sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks));
}

static inline void sk_refcnt_debug_release(const struct sock *sk)
{
	if (atomic_read(&sk->sk_refcnt) != 1)
		printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n",
		       sk->sk_prot->name, sk, atomic_read(&sk->sk_refcnt));
}
#else /* SOCK_REFCNT_DEBUG */
#define sk_refcnt_debug_inc(sk) do { } while (0)
#define sk_refcnt_debug_dec(sk) do { } while (0)
#define sk_refcnt_debug_release(sk) do { } while (0)
#endif /* SOCK_REFCNT_DEBUG */

823 824

#ifdef CONFIG_PROC_FS
Linus Torvalds's avatar
Linus Torvalds committed
825
/* Called with local bh disabled */
826 827
extern void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc);
extern int sock_prot_inuse_get(struct net *net, struct proto *proto);
828
#else
829 830
static void inline sock_prot_inuse_add(struct net *net, struct proto *prot,
		int inc)
831 832 833 834
{
}
#endif

Linus Torvalds's avatar
Linus Torvalds committed
835

836 837 838 839 840 841 842 843 844
/* With per-bucket locks this operation is not-atomic, so that
 * this version is not worse.
 */
static inline void __sk_prot_rehash(struct sock *sk)
{
	sk->sk_prot->unhash(sk);
	sk->sk_prot->hash(sk);
}

Linus Torvalds's avatar
Linus Torvalds committed
845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897
/* About 10 seconds */
#define SOCK_DESTROY_TIME (10*HZ)

/* Sockets 0-1023 can't be bound to unless you are superuser */
#define PROT_SOCK	1024

#define SHUTDOWN_MASK	3
#define RCV_SHUTDOWN	1
#define SEND_SHUTDOWN	2

#define SOCK_SNDBUF_LOCK	1
#define SOCK_RCVBUF_LOCK	2
#define SOCK_BINDADDR_LOCK	4
#define SOCK_BINDPORT_LOCK	8

/* sock_iocb: used to kick off async processing of socket ios */
struct sock_iocb {
	struct list_head	list;

	int			flags;
	int			size;
	struct socket		*sock;
	struct sock		*sk;
	struct scm_cookie	*scm;
	struct msghdr		*msg, async_msg;
	struct kiocb		*kiocb;
};

static inline struct sock_iocb *kiocb_to_siocb(struct kiocb *iocb)
{
	return (struct sock_iocb *)iocb->private;
}

static inline struct kiocb *siocb_to_kiocb(struct sock_iocb *si)
{
	return si->kiocb;
}

struct socket_alloc {
	struct socket socket;
	struct inode vfs_inode;
};

static inline struct socket *SOCKET_I(struct inode *inode)
{
	return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
}

static inline struct inode *SOCK_INODE(struct socket *socket)
{
	return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
}

898 899 900 901 902
/*
 * Functions for memory accounting
 */
extern int __sk_mem_schedule(struct sock *sk, int size, int kind);
extern void __sk_mem_reclaim(struct sock *sk);
Linus Torvalds's avatar
Linus Torvalds committed
903

904 905 906 907
#define SK_MEM_QUANTUM ((int)PAGE_SIZE)
#define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM)
#define SK_MEM_SEND	0
#define SK_MEM_RECV	1
Linus Torvalds's avatar
Linus Torvalds committed
908

909
static inline int sk_mem_pages(int amt)
Linus Torvalds's avatar
Linus Torvalds committed
910
{
911
	return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT;
Linus Torvalds's avatar
Linus Torvalds committed
912 913
}

914
static inline int sk_has_account(struct sock *sk)
Linus Torvalds's avatar
Linus Torvalds committed
915
{
916 917
	/* return true if protocol supports memory accounting */
	return !!sk->sk_prot->memory_allocated;
Linus Torvalds's avatar
Linus Torvalds committed
918 919
}

920
static inline int sk_wmem_schedule(struct sock *sk, int size)
Linus Torvalds's avatar
Linus Torvalds committed
921
{
922 923 924 925
	if (!sk_has_account(sk))
		return 1;
	return size <= sk->sk_forward_alloc ||
		__sk_mem_schedule(sk, size, SK_MEM_SEND);
Linus Torvalds's avatar
Linus Torvalds committed
926 927
}

928
static inline int sk_rmem_schedule(struct sock *sk, int size)
929
{
930 931
	if (!sk_has_account(sk))
		return 1;
932
	return size <= sk->sk_forward_alloc ||
933 934 935 936 937 938 939 940 941 942 943
		__sk_mem_schedule(sk, size, SK_MEM_RECV);
}

static inline void sk_mem_reclaim(struct sock *sk)
{
	if (!sk_has_account(sk))
		return;
	if (sk->sk_forward_alloc >= SK_MEM_QUANTUM)
		__sk_mem_reclaim(sk);
}

944 945 946 947 948 949 950 951
static inline void sk_mem_reclaim_partial(struct sock *sk)
{
	if (!sk_has_account(sk))
		return;
	if (sk->sk_forward_alloc > SK_MEM_QUANTUM)
		__sk_mem_reclaim(sk);
}

952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971
static inline void sk_mem_charge(struct sock *sk, int size)
{
	if (!sk_has_account(sk))
		return;
	sk->sk_forward_alloc -= size;
}

static inline void sk_mem_uncharge(struct sock *sk, int size)
{
	if (!sk_has_account(sk))
		return;
	sk->sk_forward_alloc += size;
}

static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb)
{
	sock_set_flag(sk, SOCK_QUEUE_SHRUNK);
	sk->sk_wmem_queued -= skb->truesize;
	sk_mem_uncharge(sk, skb->truesize);
	__kfree_skb(skb);
972 973
}

Linus Torvalds's avatar
Linus Torvalds committed
974 975 976 977 978 979 980 981 982 983 984 985 986
/* Used by processes to "lock" a socket state, so that
 * interrupts and bottom half handlers won't change it
 * from under us. It essentially blocks any incoming
 * packets, so that we won't get any new data or any
 * packets that change the state of the socket.
 *
 * While locked, BH processing will add new packets to
 * the backlog queue.  This queue is processed by the
 * owner of the socket lock right before it is released.
 *
 * Since ~2.3.5 it is also exclusive sleep lock serializing
 * accesses from user process context.
 */
987
#define sock_owned_by_user(sk)	((sk)->sk_lock.owned)
Linus Torvalds's avatar
Linus Torvalds committed
988

989 990 991 992 993 994 995 996 997
/*
 * Macro so as to not evaluate some arguments when
 * lockdep is not enabled.
 *
 * Mark both the sk_lock and the sk_lock.slock as a
 * per-address-family lock class.
 */
#define sock_lock_init_class_and_name(sk, sname, skey, name, key) 	\
do {									\
998
	sk->sk_lock.owned = 0;						\
999 1000 1001 1002 1003 1004 1005 1006 1007
	init_waitqueue_head(&sk->sk_lock.wq);				\
	spin_lock_init(&(sk)->sk_lock.slock);				\
	debug_check_no_locks_freed((void *)&(sk)->sk_lock,		\
			sizeof((sk)->sk_lock));				\
	lockdep_set_class_and_name(&(sk)->sk_lock.slock,		\
		       	(skey), (sname));				\
	lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0);	\
} while (0)

Harvey Harrison's avatar
Harvey Harrison committed
1008
extern void lock_sock_nested(struct sock *sk, int subclass);
1009 1010 1011 1012 1013 1014

static inline void lock_sock(struct sock *sk)
{
	lock_sock_nested(sk, 0);
}

Harvey Harrison's avatar
Harvey Harrison committed
1015
extern void release_sock(struct sock *sk);
Linus Torvalds's avatar
Linus Torvalds committed
1016 1017 1018

/* BH context may only use the following locking interface. */
#define bh_lock_sock(__sk)	spin_lock(&((__sk)->sk_lock.slock))
1019 1020 1021
#define bh_lock_sock_nested(__sk) \
				spin_lock_nested(&((__sk)->sk_lock.slock), \
				SINGLE_DEPTH_NESTING)
Linus Torvalds's avatar
Linus Torvalds committed
1022 1023
#define bh_unlock_sock(__sk)	spin_unlock(&((__sk)->sk_lock.slock))

Eric Dumazet's avatar
Eric Dumazet committed
1024 1025 1026 1027 1028 1029 1030 1031 1032 1033
static inline void lock_sock_bh(struct sock *sk)
{
	spin_lock_bh(&sk->sk_lock.slock);
}

static inline void unlock_sock_bh(struct sock *sk)
{
	spin_unlock_bh(&sk->sk_lock.slock);
}

1034
extern struct sock		*sk_alloc(struct net *net, int family,
1035
					  gfp_t priority,
1036
					  struct proto *prot);
Linus Torvalds's avatar
Linus Torvalds committed
1037
extern void			sk_free(struct sock *sk);
1038
extern void			sk_release_kernel(struct sock *sk);
1039
extern struct sock		*sk_clone(const struct sock *sk,
1040
					  const gfp_t priority);
Linus Torvalds's avatar
Linus Torvalds committed
1041 1042 1043

extern struct sk_buff		*sock_wmalloc(struct sock *sk,
					      unsigned long size, int force,
1044
					      gfp_t priority);
Linus Torvalds's avatar
Linus Torvalds committed
1045 1046
extern struct sk_buff		*sock_rmalloc(struct sock *sk,
					      unsigned long size, int force,
1047
					      gfp_t priority);
Linus Torvalds's avatar
Linus Torvalds committed
1048 1049 1050 1051 1052
extern void			sock_wfree(struct sk_buff *skb);
extern void			sock_rfree(struct sk_buff *skb);

extern int			sock_setsockopt(struct socket *sock, int level,
						int op, char __user *optval,
1053
						unsigned int optlen);
Linus Torvalds's avatar
Linus Torvalds committed
1054 1055 1056 1057 1058 1059 1060 1061

extern int			sock_getsockopt(struct socket *sock, int level,
						int op, char __user *optval, 
						int __user *optlen);
extern struct sk_buff 		*sock_alloc_send_skb(struct sock *sk,
						     unsigned long size,
						     int noblock,
						     int *errcode);
1062 1063 1064 1065 1066
extern struct sk_buff 		*sock_alloc_send_pskb(struct sock *sk,
						      unsigned long header_len,
						      unsigned long data_len,
						      int noblock,
						      int *errcode);
Victor Fusco's avatar
Victor Fusco committed
1067
extern void *sock_kmalloc(struct sock *sk, int size,
1068
			  gfp_t priority);
Linus Torvalds's avatar
Linus Torvalds committed
1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094
extern void sock_kfree_s(struct sock *sk, void *mem, int size);
extern void sk_send_sigurg(struct sock *sk);

/*
 * Functions to fill in entries in struct proto_ops when a protocol
 * does not implement a particular function.
 */
extern int                      sock_no_bind(struct socket *, 
					     struct sockaddr *, int);
extern int                      sock_no_connect(struct socket *,
						struct sockaddr *, int, int);
extern int                      sock_no_socketpair(struct socket *,
						   struct socket *);
extern int                      sock_no_accept(struct socket *,
					       struct socket *, int);
extern int                      sock_no_getname(struct socket *,
						struct sockaddr *, int *, int);
extern unsigned int             sock_no_poll(struct file *, struct socket *,
					     struct poll_table_struct *);
extern int                      sock_no_ioctl(struct socket *, unsigned int,
					      unsigned long);
extern int			sock_no_listen(struct socket *, int);
extern int                      sock_no_shutdown(struct socket *, int);
extern int			sock_no_getsockopt(struct socket *, int , int,
						   char __user *, int __user *);
extern int			sock_no_setsockopt(struct socket *, int, int,
1095
						   char __user *, unsigned int);
Linus Torvalds's avatar
Linus Torvalds committed
1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116
extern int                      sock_no_sendmsg(struct kiocb *, struct socket *,
						struct msghdr *, size_t);
extern int                      sock_no_recvmsg(struct kiocb *, struct socket *,
						struct msghdr *, size_t, int);
extern int			sock_no_mmap(struct file *file,
					     struct socket *sock,
					     struct vm_area_struct *vma);
extern ssize_t			sock_no_sendpage(struct socket *sock,
						struct page *page,
						int offset, size_t size, 
						int flags);

/*
 * Functions to fill in entries in struct proto_ops when a protocol
 * uses the inet style.
 */
extern int sock_common_getsockopt(struct socket *sock, int level, int optname,
				  char __user *optval, int __user *optlen);
extern int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock,
			       struct msghdr *msg, size_t size, int flags);
extern int sock_common_setsockopt(struct socket *sock, int level, int optname,
1117
				  char __user *optval, unsigned int optlen);
1118 1119 1120
extern int compat_sock_common_getsockopt(struct socket *sock, int level,
		int optname, char __user *optval, int __user *optlen);
extern int compat_sock_common_setsockopt(struct socket *sock, int level,
1121
		int optname, char __user *optval, unsigned int optlen);
Linus Torvalds's avatar
Linus Torvalds committed
1122 1123 1124 1125 1126 1127 1128 1129 1130 1131

extern void sk_common_release(struct sock *sk);

/*
 *	Default socket callbacks and setup code
 */
 
/* Initialise core socket variables */
extern void sock_init_data(struct socket *sock, struct sock *sk);

1132
/**
1133
 *	sk_filter_release - release a socket filter
1134 1135 1136 1137 1138
 *	@fp: filter to remove
 *
 *	Remove a filter from a socket and release its resources.
 */

1139 1140 1141
static inline void sk_filter_release(struct sk_filter *fp)
{
	if (atomic_dec_and_test(&fp->refcnt))
1142
		kfree(fp);
1143 1144 1145
}

static inline void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp)
Linus Torvalds's avatar
Linus Torvalds committed
1146 1147 1148 1149
{
	unsigned int size = sk_filter_len(fp);

	atomic_sub(size, &sk->sk_omem_alloc);
1150
	sk_filter_release(fp);
Linus Torvalds's avatar
Linus Torvalds committed
1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190
}

static inline void sk_filter_charge(struct sock *sk, struct sk_filter *fp)
{
	atomic_inc(&fp->refcnt);
	atomic_add(sk_filter_len(fp), &sk->sk_omem_alloc);
}

/*
 * Socket reference counting postulates.
 *
 * * Each user of socket SHOULD hold a reference count.
 * * Each access point to socket (an hash table bucket, reference from a list,
 *   running timer, skb in flight MUST hold a reference count.
 * * When reference count hits 0, it means it will never increase back.
 * * When reference count hits 0, it means that no references from
 *   outside exist to this socket and current process on current CPU
 *   is last user and may/should destroy this socket.
 * * sk_free is called from any context: process, BH, IRQ. When
 *   it is called, socket has no references from outside -> sk_free
 *   may release descendant resources allocated by the socket, but
 *   to the time when it is called, socket is NOT referenced by any
 *   hash tables, lists etc.
 * * Packets, delivered from outside (from network or from another process)
 *   and enqueued on receive/error queues SHOULD NOT grab reference count,
 *   when they sit in queue. Otherwise, packets will leak to hole, when
 *   socket is looked up by one cpu and unhasing is made by another CPU.
 *   It is true for udp/raw, netlink (leak to receive and error queues), tcp
 *   (leak to backlog). Packet socket does all the processing inside
 *   BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
 *   use separate SMP lock, so that they are prone too.
 */

/* Ungrab socket and destroy it, if it was the last reference. */
static inline void sock_put(struct sock *sk)
{
	if (atomic_dec_and_test(&sk->sk_refcnt))
		sk_free(sk);
}

1191 1192
extern int sk_receive_skb(struct sock *sk, struct sk_buff *skb,
			  const int nested);
1193

1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213
sta