include: replace linux/module.h with "struct module" wherever possible
[linux-2.6/next.git] / include / net / sock.h
blob4aa706caa2020e033f71c2015a1a6e2060e48910
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.
6 * Definitions for the AF_INET socket handler.
8 * Version: @(#)sock.h 1.0.4 05/13/93
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>
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
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.
40 #ifndef _SOCK_H
41 #define _SOCK_H
43 #include <linux/hardirq.h>
44 #include <linux/kernel.h>
45 #include <linux/list.h>
46 #include <linux/list_nulls.h>
47 #include <linux/timer.h>
48 #include <linux/cache.h>
49 #include <linux/lockdep.h>
50 #include <linux/netdevice.h>
51 #include <linux/skbuff.h> /* struct sk_buff */
52 #include <linux/mm.h>
53 #include <linux/security.h>
54 #include <linux/slab.h>
55 #include <linux/uaccess.h>
57 #include <linux/filter.h>
58 #include <linux/rculist_nulls.h>
59 #include <linux/poll.h>
61 #include <linux/atomic.h>
62 #include <net/dst.h>
63 #include <net/checksum.h>
66 * This structure really needs to be cleaned up.
67 * Most of it is for TCP, and not used by any of
68 * the other protocols.
71 /* Define this to get the SOCK_DBG debugging facility. */
72 #define SOCK_DEBUGGING
73 #ifdef SOCK_DEBUGGING
74 #define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \
75 printk(KERN_DEBUG msg); } while (0)
76 #else
77 /* Validate arguments and do nothing */
78 static inline void __attribute__ ((format (printf, 2, 3)))
79 SOCK_DEBUG(struct sock *sk, const char *msg, ...)
82 #endif
84 /* This is the per-socket lock. The spinlock provides a synchronization
85 * between user contexts and software interrupt processing, whereas the
86 * mini-semaphore synchronizes multiple users amongst themselves.
88 typedef struct {
89 spinlock_t slock;
90 int owned;
91 wait_queue_head_t wq;
93 * We express the mutex-alike socket_lock semantics
94 * to the lock validator by explicitly managing
95 * the slock as a lock variant (in addition to
96 * the slock itself):
98 #ifdef CONFIG_DEBUG_LOCK_ALLOC
99 struct lockdep_map dep_map;
100 #endif
101 } socket_lock_t;
103 struct sock;
104 struct proto;
105 struct net;
108 * struct sock_common - minimal network layer representation of sockets
109 * @skc_daddr: Foreign IPv4 addr
110 * @skc_rcv_saddr: Bound local IPv4 addr
111 * @skc_hash: hash value used with various protocol lookup tables
112 * @skc_u16hashes: two u16 hash values used by UDP lookup tables
113 * @skc_family: network address family
114 * @skc_state: Connection state
115 * @skc_reuse: %SO_REUSEADDR setting
116 * @skc_bound_dev_if: bound device index if != 0
117 * @skc_bind_node: bind hash linkage for various protocol lookup tables
118 * @skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol
119 * @skc_prot: protocol handlers inside a network family
120 * @skc_net: reference to the network namespace of this socket
121 * @skc_node: main hash linkage for various protocol lookup tables
122 * @skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol
123 * @skc_tx_queue_mapping: tx queue number for this connection
124 * @skc_refcnt: reference count
126 * This is the minimal network layer representation of sockets, the header
127 * for struct sock and struct inet_timewait_sock.
129 struct sock_common {
130 /* skc_daddr and skc_rcv_saddr must be grouped :
131 * cf INET_MATCH() and INET_TW_MATCH()
133 __be32 skc_daddr;
134 __be32 skc_rcv_saddr;
136 union {
137 unsigned int skc_hash;
138 __u16 skc_u16hashes[2];
140 unsigned short skc_family;
141 volatile unsigned char skc_state;
142 unsigned char skc_reuse;
143 int skc_bound_dev_if;
144 union {
145 struct hlist_node skc_bind_node;
146 struct hlist_nulls_node skc_portaddr_node;
148 struct proto *skc_prot;
149 #ifdef CONFIG_NET_NS
150 struct net *skc_net;
151 #endif
153 * fields between dontcopy_begin/dontcopy_end
154 * are not copied in sock_copy()
156 /* private: */
157 int skc_dontcopy_begin[0];
158 /* public: */
159 union {
160 struct hlist_node skc_node;
161 struct hlist_nulls_node skc_nulls_node;
163 int skc_tx_queue_mapping;
164 atomic_t skc_refcnt;
165 /* private: */
166 int skc_dontcopy_end[0];
167 /* public: */
171 * struct sock - network layer representation of sockets
172 * @__sk_common: shared layout with inet_timewait_sock
173 * @sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
174 * @sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
175 * @sk_lock: synchronizer
176 * @sk_rcvbuf: size of receive buffer in bytes
177 * @sk_wq: sock wait queue and async head
178 * @sk_dst_cache: destination cache
179 * @sk_dst_lock: destination cache lock
180 * @sk_policy: flow policy
181 * @sk_receive_queue: incoming packets
182 * @sk_wmem_alloc: transmit queue bytes committed
183 * @sk_write_queue: Packet sending queue
184 * @sk_async_wait_queue: DMA copied packets
185 * @sk_omem_alloc: "o" is "option" or "other"
186 * @sk_wmem_queued: persistent queue size
187 * @sk_forward_alloc: space allocated forward
188 * @sk_allocation: allocation mode
189 * @sk_sndbuf: size of send buffer in bytes
190 * @sk_flags: %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE,
191 * %SO_OOBINLINE settings, %SO_TIMESTAMPING settings
192 * @sk_no_check: %SO_NO_CHECK setting, wether or not checkup packets
193 * @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
194 * @sk_route_nocaps: forbidden route capabilities (e.g NETIF_F_GSO_MASK)
195 * @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
196 * @sk_gso_max_size: Maximum GSO segment size to build
197 * @sk_lingertime: %SO_LINGER l_linger setting
198 * @sk_backlog: always used with the per-socket spinlock held
199 * @sk_callback_lock: used with the callbacks in the end of this struct
200 * @sk_error_queue: rarely used
201 * @sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt,
202 * IPV6_ADDRFORM for instance)
203 * @sk_err: last error
204 * @sk_err_soft: errors that don't cause failure but are the cause of a
205 * persistent failure not just 'timed out'
206 * @sk_drops: raw/udp drops counter
207 * @sk_ack_backlog: current listen backlog
208 * @sk_max_ack_backlog: listen backlog set in listen()
209 * @sk_priority: %SO_PRIORITY setting
210 * @sk_type: socket type (%SOCK_STREAM, etc)
211 * @sk_protocol: which protocol this socket belongs in this network family
212 * @sk_peer_pid: &struct pid for this socket's peer
213 * @sk_peer_cred: %SO_PEERCRED setting
214 * @sk_rcvlowat: %SO_RCVLOWAT setting
215 * @sk_rcvtimeo: %SO_RCVTIMEO setting
216 * @sk_sndtimeo: %SO_SNDTIMEO setting
217 * @sk_rxhash: flow hash received from netif layer
218 * @sk_filter: socket filtering instructions
219 * @sk_protinfo: private area, net family specific, when not using slab
220 * @sk_timer: sock cleanup timer
221 * @sk_stamp: time stamp of last packet received
222 * @sk_socket: Identd and reporting IO signals
223 * @sk_user_data: RPC layer private data
224 * @sk_sndmsg_page: cached page for sendmsg
225 * @sk_sndmsg_off: cached offset for sendmsg
226 * @sk_send_head: front of stuff to transmit
227 * @sk_security: used by security modules
228 * @sk_mark: generic packet mark
229 * @sk_classid: this socket's cgroup classid
230 * @sk_write_pending: a write to stream socket waits to start
231 * @sk_state_change: callback to indicate change in the state of the sock
232 * @sk_data_ready: callback to indicate there is data to be processed
233 * @sk_write_space: callback to indicate there is bf sending space available
234 * @sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
235 * @sk_backlog_rcv: callback to process the backlog
236 * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
238 struct sock {
240 * Now struct inet_timewait_sock also uses sock_common, so please just
241 * don't add nothing before this first member (__sk_common) --acme
243 struct sock_common __sk_common;
244 #define sk_node __sk_common.skc_node
245 #define sk_nulls_node __sk_common.skc_nulls_node
246 #define sk_refcnt __sk_common.skc_refcnt
247 #define sk_tx_queue_mapping __sk_common.skc_tx_queue_mapping
249 #define sk_dontcopy_begin __sk_common.skc_dontcopy_begin
250 #define sk_dontcopy_end __sk_common.skc_dontcopy_end
251 #define sk_hash __sk_common.skc_hash
252 #define sk_family __sk_common.skc_family
253 #define sk_state __sk_common.skc_state
254 #define sk_reuse __sk_common.skc_reuse
255 #define sk_bound_dev_if __sk_common.skc_bound_dev_if
256 #define sk_bind_node __sk_common.skc_bind_node
257 #define sk_prot __sk_common.skc_prot
258 #define sk_net __sk_common.skc_net
259 socket_lock_t sk_lock;
260 struct sk_buff_head sk_receive_queue;
262 * The backlog queue is special, it is always used with
263 * the per-socket spinlock held and requires low latency
264 * access. Therefore we special case it's implementation.
265 * Note : rmem_alloc is in this structure to fill a hole
266 * on 64bit arches, not because its logically part of
267 * backlog.
269 struct {
270 atomic_t rmem_alloc;
271 int len;
272 struct sk_buff *head;
273 struct sk_buff *tail;
274 } sk_backlog;
275 #define sk_rmem_alloc sk_backlog.rmem_alloc
276 int sk_forward_alloc;
277 #ifdef CONFIG_RPS
278 __u32 sk_rxhash;
279 #endif
280 atomic_t sk_drops;
281 int sk_rcvbuf;
283 struct sk_filter __rcu *sk_filter;
284 struct socket_wq __rcu *sk_wq;
286 #ifdef CONFIG_NET_DMA
287 struct sk_buff_head sk_async_wait_queue;
288 #endif
290 #ifdef CONFIG_XFRM
291 struct xfrm_policy *sk_policy[2];
292 #endif
293 unsigned long sk_flags;
294 struct dst_entry *sk_dst_cache;
295 spinlock_t sk_dst_lock;
296 atomic_t sk_wmem_alloc;
297 atomic_t sk_omem_alloc;
298 int sk_sndbuf;
299 struct sk_buff_head sk_write_queue;
300 kmemcheck_bitfield_begin(flags);
301 unsigned int sk_shutdown : 2,
302 sk_no_check : 2,
303 sk_userlocks : 4,
304 sk_protocol : 8,
305 sk_type : 16;
306 kmemcheck_bitfield_end(flags);
307 int sk_wmem_queued;
308 gfp_t sk_allocation;
309 int sk_route_caps;
310 int sk_route_nocaps;
311 int sk_gso_type;
312 unsigned int sk_gso_max_size;
313 int sk_rcvlowat;
314 unsigned long sk_lingertime;
315 struct sk_buff_head sk_error_queue;
316 struct proto *sk_prot_creator;
317 rwlock_t sk_callback_lock;
318 int sk_err,
319 sk_err_soft;
320 unsigned short sk_ack_backlog;
321 unsigned short sk_max_ack_backlog;
322 __u32 sk_priority;
323 struct pid *sk_peer_pid;
324 const struct cred *sk_peer_cred;
325 long sk_rcvtimeo;
326 long sk_sndtimeo;
327 void *sk_protinfo;
328 struct timer_list sk_timer;
329 ktime_t sk_stamp;
330 struct socket *sk_socket;
331 void *sk_user_data;
332 struct page *sk_sndmsg_page;
333 struct sk_buff *sk_send_head;
334 __u32 sk_sndmsg_off;
335 int sk_write_pending;
336 #ifdef CONFIG_SECURITY
337 void *sk_security;
338 #endif
339 __u32 sk_mark;
340 u32 sk_classid;
341 void (*sk_state_change)(struct sock *sk);
342 void (*sk_data_ready)(struct sock *sk, int bytes);
343 void (*sk_write_space)(struct sock *sk);
344 void (*sk_error_report)(struct sock *sk);
345 int (*sk_backlog_rcv)(struct sock *sk,
346 struct sk_buff *skb);
347 void (*sk_destruct)(struct sock *sk);
351 * Hashed lists helper routines
353 static inline struct sock *sk_entry(const struct hlist_node *node)
355 return hlist_entry(node, struct sock, sk_node);
358 static inline struct sock *__sk_head(const struct hlist_head *head)
360 return hlist_entry(head->first, struct sock, sk_node);
363 static inline struct sock *sk_head(const struct hlist_head *head)
365 return hlist_empty(head) ? NULL : __sk_head(head);
368 static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head)
370 return hlist_nulls_entry(head->first, struct sock, sk_nulls_node);
373 static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head)
375 return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head);
378 static inline struct sock *sk_next(const struct sock *sk)
380 return sk->sk_node.next ?
381 hlist_entry(sk->sk_node.next, struct sock, sk_node) : NULL;
384 static inline struct sock *sk_nulls_next(const struct sock *sk)
386 return (!is_a_nulls(sk->sk_nulls_node.next)) ?
387 hlist_nulls_entry(sk->sk_nulls_node.next,
388 struct sock, sk_nulls_node) :
389 NULL;
392 static inline int sk_unhashed(const struct sock *sk)
394 return hlist_unhashed(&sk->sk_node);
397 static inline int sk_hashed(const struct sock *sk)
399 return !sk_unhashed(sk);
402 static __inline__ void sk_node_init(struct hlist_node *node)
404 node->pprev = NULL;
407 static __inline__ void sk_nulls_node_init(struct hlist_nulls_node *node)
409 node->pprev = NULL;
412 static __inline__ void __sk_del_node(struct sock *sk)
414 __hlist_del(&sk->sk_node);
417 /* NB: equivalent to hlist_del_init_rcu */
418 static __inline__ int __sk_del_node_init(struct sock *sk)
420 if (sk_hashed(sk)) {
421 __sk_del_node(sk);
422 sk_node_init(&sk->sk_node);
423 return 1;
425 return 0;
428 /* Grab socket reference count. This operation is valid only
429 when sk is ALREADY grabbed f.e. it is found in hash table
430 or a list and the lookup is made under lock preventing hash table
431 modifications.
434 static inline void sock_hold(struct sock *sk)
436 atomic_inc(&sk->sk_refcnt);
439 /* Ungrab socket in the context, which assumes that socket refcnt
440 cannot hit zero, f.e. it is true in context of any socketcall.
442 static inline void __sock_put(struct sock *sk)
444 atomic_dec(&sk->sk_refcnt);
447 static __inline__ int sk_del_node_init(struct sock *sk)
449 int rc = __sk_del_node_init(sk);
451 if (rc) {
452 /* paranoid for a while -acme */
453 WARN_ON(atomic_read(&sk->sk_refcnt) == 1);
454 __sock_put(sk);
456 return rc;
458 #define sk_del_node_init_rcu(sk) sk_del_node_init(sk)
460 static __inline__ int __sk_nulls_del_node_init_rcu(struct sock *sk)
462 if (sk_hashed(sk)) {
463 hlist_nulls_del_init_rcu(&sk->sk_nulls_node);
464 return 1;
466 return 0;
469 static __inline__ int sk_nulls_del_node_init_rcu(struct sock *sk)
471 int rc = __sk_nulls_del_node_init_rcu(sk);
473 if (rc) {
474 /* paranoid for a while -acme */
475 WARN_ON(atomic_read(&sk->sk_refcnt) == 1);
476 __sock_put(sk);
478 return rc;
481 static __inline__ void __sk_add_node(struct sock *sk, struct hlist_head *list)
483 hlist_add_head(&sk->sk_node, list);
486 static __inline__ void sk_add_node(struct sock *sk, struct hlist_head *list)
488 sock_hold(sk);
489 __sk_add_node(sk, list);
492 static __inline__ void sk_add_node_rcu(struct sock *sk, struct hlist_head *list)
494 sock_hold(sk);
495 hlist_add_head_rcu(&sk->sk_node, list);
498 static __inline__ void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
500 hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list);
503 static __inline__ void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
505 sock_hold(sk);
506 __sk_nulls_add_node_rcu(sk, list);
509 static __inline__ void __sk_del_bind_node(struct sock *sk)
511 __hlist_del(&sk->sk_bind_node);
514 static __inline__ void sk_add_bind_node(struct sock *sk,
515 struct hlist_head *list)
517 hlist_add_head(&sk->sk_bind_node, list);
520 #define sk_for_each(__sk, node, list) \
521 hlist_for_each_entry(__sk, node, list, sk_node)
522 #define sk_for_each_rcu(__sk, node, list) \
523 hlist_for_each_entry_rcu(__sk, node, list, sk_node)
524 #define sk_nulls_for_each(__sk, node, list) \
525 hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)
526 #define sk_nulls_for_each_rcu(__sk, node, list) \
527 hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)
528 #define sk_for_each_from(__sk, node) \
529 if (__sk && ({ node = &(__sk)->sk_node; 1; })) \
530 hlist_for_each_entry_from(__sk, node, sk_node)
531 #define sk_nulls_for_each_from(__sk, node) \
532 if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \
533 hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node)
534 #define sk_for_each_safe(__sk, node, tmp, list) \
535 hlist_for_each_entry_safe(__sk, node, tmp, list, sk_node)
536 #define sk_for_each_bound(__sk, node, list) \
537 hlist_for_each_entry(__sk, node, list, sk_bind_node)
539 /* Sock flags */
540 enum sock_flags {
541 SOCK_DEAD,
542 SOCK_DONE,
543 SOCK_URGINLINE,
544 SOCK_KEEPOPEN,
545 SOCK_LINGER,
546 SOCK_DESTROY,
547 SOCK_BROADCAST,
548 SOCK_TIMESTAMP,
549 SOCK_ZAPPED,
550 SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */
551 SOCK_DBG, /* %SO_DEBUG setting */
552 SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
553 SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */
554 SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
555 SOCK_QUEUE_SHRUNK, /* write queue has been shrunk recently */
556 SOCK_TIMESTAMPING_TX_HARDWARE, /* %SOF_TIMESTAMPING_TX_HARDWARE */
557 SOCK_TIMESTAMPING_TX_SOFTWARE, /* %SOF_TIMESTAMPING_TX_SOFTWARE */
558 SOCK_TIMESTAMPING_RX_HARDWARE, /* %SOF_TIMESTAMPING_RX_HARDWARE */
559 SOCK_TIMESTAMPING_RX_SOFTWARE, /* %SOF_TIMESTAMPING_RX_SOFTWARE */
560 SOCK_TIMESTAMPING_SOFTWARE, /* %SOF_TIMESTAMPING_SOFTWARE */
561 SOCK_TIMESTAMPING_RAW_HARDWARE, /* %SOF_TIMESTAMPING_RAW_HARDWARE */
562 SOCK_TIMESTAMPING_SYS_HARDWARE, /* %SOF_TIMESTAMPING_SYS_HARDWARE */
563 SOCK_FASYNC, /* fasync() active */
564 SOCK_RXQ_OVFL,
565 SOCK_ZEROCOPY, /* buffers from userspace */
568 static inline void sock_copy_flags(struct sock *nsk, struct sock *osk)
570 nsk->sk_flags = osk->sk_flags;
573 static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
575 __set_bit(flag, &sk->sk_flags);
578 static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag)
580 __clear_bit(flag, &sk->sk_flags);
583 static inline int sock_flag(struct sock *sk, enum sock_flags flag)
585 return test_bit(flag, &sk->sk_flags);
588 static inline void sk_acceptq_removed(struct sock *sk)
590 sk->sk_ack_backlog--;
593 static inline void sk_acceptq_added(struct sock *sk)
595 sk->sk_ack_backlog++;
598 static inline int sk_acceptq_is_full(struct sock *sk)
600 return sk->sk_ack_backlog > sk->sk_max_ack_backlog;
604 * Compute minimal free write space needed to queue new packets.
606 static inline int sk_stream_min_wspace(struct sock *sk)
608 return sk->sk_wmem_queued >> 1;
611 static inline int sk_stream_wspace(struct sock *sk)
613 return sk->sk_sndbuf - sk->sk_wmem_queued;
616 extern void sk_stream_write_space(struct sock *sk);
618 static inline int sk_stream_memory_free(struct sock *sk)
620 return sk->sk_wmem_queued < sk->sk_sndbuf;
623 /* OOB backlog add */
624 static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
626 /* dont let skb dst not refcounted, we are going to leave rcu lock */
627 skb_dst_force(skb);
629 if (!sk->sk_backlog.tail)
630 sk->sk_backlog.head = skb;
631 else
632 sk->sk_backlog.tail->next = skb;
634 sk->sk_backlog.tail = skb;
635 skb->next = NULL;
639 * Take into account size of receive queue and backlog queue
641 static inline bool sk_rcvqueues_full(const struct sock *sk, const struct sk_buff *skb)
643 unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc);
645 return qsize + skb->truesize > sk->sk_rcvbuf;
648 /* The per-socket spinlock must be held here. */
649 static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb)
651 if (sk_rcvqueues_full(sk, skb))
652 return -ENOBUFS;
654 __sk_add_backlog(sk, skb);
655 sk->sk_backlog.len += skb->truesize;
656 return 0;
659 static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
661 return sk->sk_backlog_rcv(sk, skb);
664 static inline void sock_rps_record_flow(const struct sock *sk)
666 #ifdef CONFIG_RPS
667 struct rps_sock_flow_table *sock_flow_table;
669 rcu_read_lock();
670 sock_flow_table = rcu_dereference(rps_sock_flow_table);
671 rps_record_sock_flow(sock_flow_table, sk->sk_rxhash);
672 rcu_read_unlock();
673 #endif
676 static inline void sock_rps_reset_flow(const struct sock *sk)
678 #ifdef CONFIG_RPS
679 struct rps_sock_flow_table *sock_flow_table;
681 rcu_read_lock();
682 sock_flow_table = rcu_dereference(rps_sock_flow_table);
683 rps_reset_sock_flow(sock_flow_table, sk->sk_rxhash);
684 rcu_read_unlock();
685 #endif
688 static inline void sock_rps_save_rxhash(struct sock *sk, u32 rxhash)
690 #ifdef CONFIG_RPS
691 if (unlikely(sk->sk_rxhash != rxhash)) {
692 sock_rps_reset_flow(sk);
693 sk->sk_rxhash = rxhash;
695 #endif
698 #define sk_wait_event(__sk, __timeo, __condition) \
699 ({ int __rc; \
700 release_sock(__sk); \
701 __rc = __condition; \
702 if (!__rc) { \
703 *(__timeo) = schedule_timeout(*(__timeo)); \
705 lock_sock(__sk); \
706 __rc = __condition; \
707 __rc; \
710 extern int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
711 extern int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
712 extern void sk_stream_wait_close(struct sock *sk, long timeo_p);
713 extern int sk_stream_error(struct sock *sk, int flags, int err);
714 extern void sk_stream_kill_queues(struct sock *sk);
716 extern int sk_wait_data(struct sock *sk, long *timeo);
718 struct request_sock_ops;
719 struct timewait_sock_ops;
720 struct inet_hashinfo;
721 struct raw_hashinfo;
722 struct module;
724 /* Networking protocol blocks we attach to sockets.
725 * socket layer -> transport layer interface
726 * transport -> network interface is defined by struct inet_proto
728 struct proto {
729 void (*close)(struct sock *sk,
730 long timeout);
731 int (*connect)(struct sock *sk,
732 struct sockaddr *uaddr,
733 int addr_len);
734 int (*disconnect)(struct sock *sk, int flags);
736 struct sock * (*accept) (struct sock *sk, int flags, int *err);
738 int (*ioctl)(struct sock *sk, int cmd,
739 unsigned long arg);
740 int (*init)(struct sock *sk);
741 void (*destroy)(struct sock *sk);
742 void (*shutdown)(struct sock *sk, int how);
743 int (*setsockopt)(struct sock *sk, int level,
744 int optname, char __user *optval,
745 unsigned int optlen);
746 int (*getsockopt)(struct sock *sk, int level,
747 int optname, char __user *optval,
748 int __user *option);
749 #ifdef CONFIG_COMPAT
750 int (*compat_setsockopt)(struct sock *sk,
751 int level,
752 int optname, char __user *optval,
753 unsigned int optlen);
754 int (*compat_getsockopt)(struct sock *sk,
755 int level,
756 int optname, char __user *optval,
757 int __user *option);
758 int (*compat_ioctl)(struct sock *sk,
759 unsigned int cmd, unsigned long arg);
760 #endif
761 int (*sendmsg)(struct kiocb *iocb, struct sock *sk,
762 struct msghdr *msg, size_t len);
763 int (*recvmsg)(struct kiocb *iocb, struct sock *sk,
764 struct msghdr *msg,
765 size_t len, int noblock, int flags,
766 int *addr_len);
767 int (*sendpage)(struct sock *sk, struct page *page,
768 int offset, size_t size, int flags);
769 int (*bind)(struct sock *sk,
770 struct sockaddr *uaddr, int addr_len);
772 int (*backlog_rcv) (struct sock *sk,
773 struct sk_buff *skb);
775 /* Keeping track of sk's, looking them up, and port selection methods. */
776 void (*hash)(struct sock *sk);
777 void (*unhash)(struct sock *sk);
778 void (*rehash)(struct sock *sk);
779 int (*get_port)(struct sock *sk, unsigned short snum);
780 void (*clear_sk)(struct sock *sk, int size);
782 /* Keeping track of sockets in use */
783 #ifdef CONFIG_PROC_FS
784 unsigned int inuse_idx;
785 #endif
787 /* Memory pressure */
788 void (*enter_memory_pressure)(struct sock *sk);
789 atomic_long_t *memory_allocated; /* Current allocated memory. */
790 struct percpu_counter *sockets_allocated; /* Current number of sockets. */
792 * Pressure flag: try to collapse.
793 * Technical note: it is used by multiple contexts non atomically.
794 * All the __sk_mem_schedule() is of this nature: accounting
795 * is strict, actions are advisory and have some latency.
797 int *memory_pressure;
798 long *sysctl_mem;
799 int *sysctl_wmem;
800 int *sysctl_rmem;
801 int max_header;
802 bool no_autobind;
804 struct kmem_cache *slab;
805 unsigned int obj_size;
806 int slab_flags;
808 struct percpu_counter *orphan_count;
810 struct request_sock_ops *rsk_prot;
811 struct timewait_sock_ops *twsk_prot;
813 union {
814 struct inet_hashinfo *hashinfo;
815 struct udp_table *udp_table;
816 struct raw_hashinfo *raw_hash;
817 } h;
819 struct module *owner;
821 char name[32];
823 struct list_head node;
824 #ifdef SOCK_REFCNT_DEBUG
825 atomic_t socks;
826 #endif
829 extern int proto_register(struct proto *prot, int alloc_slab);
830 extern void proto_unregister(struct proto *prot);
832 #ifdef SOCK_REFCNT_DEBUG
833 static inline void sk_refcnt_debug_inc(struct sock *sk)
835 atomic_inc(&sk->sk_prot->socks);
838 static inline void sk_refcnt_debug_dec(struct sock *sk)
840 atomic_dec(&sk->sk_prot->socks);
841 printk(KERN_DEBUG "%s socket %p released, %d are still alive\n",
842 sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks));
845 static inline void sk_refcnt_debug_release(const struct sock *sk)
847 if (atomic_read(&sk->sk_refcnt) != 1)
848 printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n",
849 sk->sk_prot->name, sk, atomic_read(&sk->sk_refcnt));
851 #else /* SOCK_REFCNT_DEBUG */
852 #define sk_refcnt_debug_inc(sk) do { } while (0)
853 #define sk_refcnt_debug_dec(sk) do { } while (0)
854 #define sk_refcnt_debug_release(sk) do { } while (0)
855 #endif /* SOCK_REFCNT_DEBUG */
858 #ifdef CONFIG_PROC_FS
859 /* Called with local bh disabled */
860 extern void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc);
861 extern int sock_prot_inuse_get(struct net *net, struct proto *proto);
862 #else
863 static void inline sock_prot_inuse_add(struct net *net, struct proto *prot,
864 int inc)
867 #endif
870 /* With per-bucket locks this operation is not-atomic, so that
871 * this version is not worse.
873 static inline void __sk_prot_rehash(struct sock *sk)
875 sk->sk_prot->unhash(sk);
876 sk->sk_prot->hash(sk);
879 void sk_prot_clear_portaddr_nulls(struct sock *sk, int size);
881 /* About 10 seconds */
882 #define SOCK_DESTROY_TIME (10*HZ)
884 /* Sockets 0-1023 can't be bound to unless you are superuser */
885 #define PROT_SOCK 1024
887 #define SHUTDOWN_MASK 3
888 #define RCV_SHUTDOWN 1
889 #define SEND_SHUTDOWN 2
891 #define SOCK_SNDBUF_LOCK 1
892 #define SOCK_RCVBUF_LOCK 2
893 #define SOCK_BINDADDR_LOCK 4
894 #define SOCK_BINDPORT_LOCK 8
896 /* sock_iocb: used to kick off async processing of socket ios */
897 struct sock_iocb {
898 struct list_head list;
900 int flags;
901 int size;
902 struct socket *sock;
903 struct sock *sk;
904 struct scm_cookie *scm;
905 struct msghdr *msg, async_msg;
906 struct kiocb *kiocb;
909 static inline struct sock_iocb *kiocb_to_siocb(struct kiocb *iocb)
911 return (struct sock_iocb *)iocb->private;
914 static inline struct kiocb *siocb_to_kiocb(struct sock_iocb *si)
916 return si->kiocb;
919 struct socket_alloc {
920 struct socket socket;
921 struct inode vfs_inode;
924 static inline struct socket *SOCKET_I(struct inode *inode)
926 return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
929 static inline struct inode *SOCK_INODE(struct socket *socket)
931 return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
935 * Functions for memory accounting
937 extern int __sk_mem_schedule(struct sock *sk, int size, int kind);
938 extern void __sk_mem_reclaim(struct sock *sk);
940 #define SK_MEM_QUANTUM ((int)PAGE_SIZE)
941 #define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM)
942 #define SK_MEM_SEND 0
943 #define SK_MEM_RECV 1
945 static inline int sk_mem_pages(int amt)
947 return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT;
950 static inline int sk_has_account(struct sock *sk)
952 /* return true if protocol supports memory accounting */
953 return !!sk->sk_prot->memory_allocated;
956 static inline int sk_wmem_schedule(struct sock *sk, int size)
958 if (!sk_has_account(sk))
959 return 1;
960 return size <= sk->sk_forward_alloc ||
961 __sk_mem_schedule(sk, size, SK_MEM_SEND);
964 static inline int sk_rmem_schedule(struct sock *sk, int size)
966 if (!sk_has_account(sk))
967 return 1;
968 return size <= sk->sk_forward_alloc ||
969 __sk_mem_schedule(sk, size, SK_MEM_RECV);
972 static inline void sk_mem_reclaim(struct sock *sk)
974 if (!sk_has_account(sk))
975 return;
976 if (sk->sk_forward_alloc >= SK_MEM_QUANTUM)
977 __sk_mem_reclaim(sk);
980 static inline void sk_mem_reclaim_partial(struct sock *sk)
982 if (!sk_has_account(sk))
983 return;
984 if (sk->sk_forward_alloc > SK_MEM_QUANTUM)
985 __sk_mem_reclaim(sk);
988 static inline void sk_mem_charge(struct sock *sk, int size)
990 if (!sk_has_account(sk))
991 return;
992 sk->sk_forward_alloc -= size;
995 static inline void sk_mem_uncharge(struct sock *sk, int size)
997 if (!sk_has_account(sk))
998 return;
999 sk->sk_forward_alloc += size;
1002 static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb)
1004 sock_set_flag(sk, SOCK_QUEUE_SHRUNK);
1005 sk->sk_wmem_queued -= skb->truesize;
1006 sk_mem_uncharge(sk, skb->truesize);
1007 __kfree_skb(skb);
1010 /* Used by processes to "lock" a socket state, so that
1011 * interrupts and bottom half handlers won't change it
1012 * from under us. It essentially blocks any incoming
1013 * packets, so that we won't get any new data or any
1014 * packets that change the state of the socket.
1016 * While locked, BH processing will add new packets to
1017 * the backlog queue. This queue is processed by the
1018 * owner of the socket lock right before it is released.
1020 * Since ~2.3.5 it is also exclusive sleep lock serializing
1021 * accesses from user process context.
1023 #define sock_owned_by_user(sk) ((sk)->sk_lock.owned)
1026 * Macro so as to not evaluate some arguments when
1027 * lockdep is not enabled.
1029 * Mark both the sk_lock and the sk_lock.slock as a
1030 * per-address-family lock class.
1032 #define sock_lock_init_class_and_name(sk, sname, skey, name, key) \
1033 do { \
1034 sk->sk_lock.owned = 0; \
1035 init_waitqueue_head(&sk->sk_lock.wq); \
1036 spin_lock_init(&(sk)->sk_lock.slock); \
1037 debug_check_no_locks_freed((void *)&(sk)->sk_lock, \
1038 sizeof((sk)->sk_lock)); \
1039 lockdep_set_class_and_name(&(sk)->sk_lock.slock, \
1040 (skey), (sname)); \
1041 lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \
1042 } while (0)
1044 extern void lock_sock_nested(struct sock *sk, int subclass);
1046 static inline void lock_sock(struct sock *sk)
1048 lock_sock_nested(sk, 0);
1051 extern void release_sock(struct sock *sk);
1053 /* BH context may only use the following locking interface. */
1054 #define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock))
1055 #define bh_lock_sock_nested(__sk) \
1056 spin_lock_nested(&((__sk)->sk_lock.slock), \
1057 SINGLE_DEPTH_NESTING)
1058 #define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock))
1060 extern bool lock_sock_fast(struct sock *sk);
1062 * unlock_sock_fast - complement of lock_sock_fast
1063 * @sk: socket
1064 * @slow: slow mode
1066 * fast unlock socket for user context.
1067 * If slow mode is on, we call regular release_sock()
1069 static inline void unlock_sock_fast(struct sock *sk, bool slow)
1071 if (slow)
1072 release_sock(sk);
1073 else
1074 spin_unlock_bh(&sk->sk_lock.slock);
1078 extern struct sock *sk_alloc(struct net *net, int family,
1079 gfp_t priority,
1080 struct proto *prot);
1081 extern void sk_free(struct sock *sk);
1082 extern void sk_release_kernel(struct sock *sk);
1083 extern struct sock *sk_clone(const struct sock *sk,
1084 const gfp_t priority);
1086 extern struct sk_buff *sock_wmalloc(struct sock *sk,
1087 unsigned long size, int force,
1088 gfp_t priority);
1089 extern struct sk_buff *sock_rmalloc(struct sock *sk,
1090 unsigned long size, int force,
1091 gfp_t priority);
1092 extern void sock_wfree(struct sk_buff *skb);
1093 extern void sock_rfree(struct sk_buff *skb);
1095 extern int sock_setsockopt(struct socket *sock, int level,
1096 int op, char __user *optval,
1097 unsigned int optlen);
1099 extern int sock_getsockopt(struct socket *sock, int level,
1100 int op, char __user *optval,
1101 int __user *optlen);
1102 extern struct sk_buff *sock_alloc_send_skb(struct sock *sk,
1103 unsigned long size,
1104 int noblock,
1105 int *errcode);
1106 extern struct sk_buff *sock_alloc_send_pskb(struct sock *sk,
1107 unsigned long header_len,
1108 unsigned long data_len,
1109 int noblock,
1110 int *errcode);
1111 extern void *sock_kmalloc(struct sock *sk, int size,
1112 gfp_t priority);
1113 extern void sock_kfree_s(struct sock *sk, void *mem, int size);
1114 extern void sk_send_sigurg(struct sock *sk);
1116 #ifdef CONFIG_CGROUPS
1117 extern void sock_update_classid(struct sock *sk);
1118 #else
1119 static inline void sock_update_classid(struct sock *sk)
1122 #endif
1125 * Functions to fill in entries in struct proto_ops when a protocol
1126 * does not implement a particular function.
1128 extern int sock_no_bind(struct socket *,
1129 struct sockaddr *, int);
1130 extern int sock_no_connect(struct socket *,
1131 struct sockaddr *, int, int);
1132 extern int sock_no_socketpair(struct socket *,
1133 struct socket *);
1134 extern int sock_no_accept(struct socket *,
1135 struct socket *, int);
1136 extern int sock_no_getname(struct socket *,
1137 struct sockaddr *, int *, int);
1138 extern unsigned int sock_no_poll(struct file *, struct socket *,
1139 struct poll_table_struct *);
1140 extern int sock_no_ioctl(struct socket *, unsigned int,
1141 unsigned long);
1142 extern int sock_no_listen(struct socket *, int);
1143 extern int sock_no_shutdown(struct socket *, int);
1144 extern int sock_no_getsockopt(struct socket *, int , int,
1145 char __user *, int __user *);
1146 extern int sock_no_setsockopt(struct socket *, int, int,
1147 char __user *, unsigned int);
1148 extern int sock_no_sendmsg(struct kiocb *, struct socket *,
1149 struct msghdr *, size_t);
1150 extern int sock_no_recvmsg(struct kiocb *, struct socket *,
1151 struct msghdr *, size_t, int);
1152 extern int sock_no_mmap(struct file *file,
1153 struct socket *sock,
1154 struct vm_area_struct *vma);
1155 extern ssize_t sock_no_sendpage(struct socket *sock,
1156 struct page *page,
1157 int offset, size_t size,
1158 int flags);
1161 * Functions to fill in entries in struct proto_ops when a protocol
1162 * uses the inet style.
1164 extern int sock_common_getsockopt(struct socket *sock, int level, int optname,
1165 char __user *optval, int __user *optlen);
1166 extern int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock,
1167 struct msghdr *msg, size_t size, int flags);
1168 extern int sock_common_setsockopt(struct socket *sock, int level, int optname,
1169 char __user *optval, unsigned int optlen);
1170 extern int compat_sock_common_getsockopt(struct socket *sock, int level,
1171 int optname, char __user *optval, int __user *optlen);
1172 extern int compat_sock_common_setsockopt(struct socket *sock, int level,
1173 int optname, char __user *optval, unsigned int optlen);
1175 extern void sk_common_release(struct sock *sk);
1178 * Default socket callbacks and setup code
1181 /* Initialise core socket variables */
1182 extern void sock_init_data(struct socket *sock, struct sock *sk);
1184 extern void sk_filter_release_rcu(struct rcu_head *rcu);
1187 * sk_filter_release - release a socket filter
1188 * @fp: filter to remove
1190 * Remove a filter from a socket and release its resources.
1193 static inline void sk_filter_release(struct sk_filter *fp)
1195 if (atomic_dec_and_test(&fp->refcnt))
1196 call_rcu(&fp->rcu, sk_filter_release_rcu);
1199 static inline void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp)
1201 unsigned int size = sk_filter_len(fp);
1203 atomic_sub(size, &sk->sk_omem_alloc);
1204 sk_filter_release(fp);
1207 static inline void sk_filter_charge(struct sock *sk, struct sk_filter *fp)
1209 atomic_inc(&fp->refcnt);
1210 atomic_add(sk_filter_len(fp), &sk->sk_omem_alloc);
1214 * Socket reference counting postulates.
1216 * * Each user of socket SHOULD hold a reference count.
1217 * * Each access point to socket (an hash table bucket, reference from a list,
1218 * running timer, skb in flight MUST hold a reference count.
1219 * * When reference count hits 0, it means it will never increase back.
1220 * * When reference count hits 0, it means that no references from
1221 * outside exist to this socket and current process on current CPU
1222 * is last user and may/should destroy this socket.
1223 * * sk_free is called from any context: process, BH, IRQ. When
1224 * it is called, socket has no references from outside -> sk_free
1225 * may release descendant resources allocated by the socket, but
1226 * to the time when it is called, socket is NOT referenced by any
1227 * hash tables, lists etc.
1228 * * Packets, delivered from outside (from network or from another process)
1229 * and enqueued on receive/error queues SHOULD NOT grab reference count,
1230 * when they sit in queue. Otherwise, packets will leak to hole, when
1231 * socket is looked up by one cpu and unhasing is made by another CPU.
1232 * It is true for udp/raw, netlink (leak to receive and error queues), tcp
1233 * (leak to backlog). Packet socket does all the processing inside
1234 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
1235 * use separate SMP lock, so that they are prone too.
1238 /* Ungrab socket and destroy it, if it was the last reference. */
1239 static inline void sock_put(struct sock *sk)
1241 if (atomic_dec_and_test(&sk->sk_refcnt))
1242 sk_free(sk);
1245 extern int sk_receive_skb(struct sock *sk, struct sk_buff *skb,
1246 const int nested);
1248 static inline void sk_tx_queue_set(struct sock *sk, int tx_queue)
1250 sk->sk_tx_queue_mapping = tx_queue;
1253 static inline void sk_tx_queue_clear(struct sock *sk)
1255 sk->sk_tx_queue_mapping = -1;
1258 static inline int sk_tx_queue_get(const struct sock *sk)
1260 return sk ? sk->sk_tx_queue_mapping : -1;
1263 static inline void sk_set_socket(struct sock *sk, struct socket *sock)
1265 sk_tx_queue_clear(sk);
1266 sk->sk_socket = sock;
1269 static inline wait_queue_head_t *sk_sleep(struct sock *sk)
1271 BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0);
1272 return &rcu_dereference_raw(sk->sk_wq)->wait;
1274 /* Detach socket from process context.
1275 * Announce socket dead, detach it from wait queue and inode.
1276 * Note that parent inode held reference count on this struct sock,
1277 * we do not release it in this function, because protocol
1278 * probably wants some additional cleanups or even continuing
1279 * to work with this socket (TCP).
1281 static inline void sock_orphan(struct sock *sk)
1283 write_lock_bh(&sk->sk_callback_lock);
1284 sock_set_flag(sk, SOCK_DEAD);
1285 sk_set_socket(sk, NULL);
1286 sk->sk_wq = NULL;
1287 write_unlock_bh(&sk->sk_callback_lock);
1290 static inline void sock_graft(struct sock *sk, struct socket *parent)
1292 write_lock_bh(&sk->sk_callback_lock);
1293 sk->sk_wq = parent->wq;
1294 parent->sk = sk;
1295 sk_set_socket(sk, parent);
1296 security_sock_graft(sk, parent);
1297 write_unlock_bh(&sk->sk_callback_lock);
1300 extern int sock_i_uid(struct sock *sk);
1301 extern unsigned long sock_i_ino(struct sock *sk);
1303 static inline struct dst_entry *
1304 __sk_dst_get(struct sock *sk)
1306 return rcu_dereference_check(sk->sk_dst_cache, sock_owned_by_user(sk) ||
1307 lockdep_is_held(&sk->sk_lock.slock));
1310 static inline struct dst_entry *
1311 sk_dst_get(struct sock *sk)
1313 struct dst_entry *dst;
1315 rcu_read_lock();
1316 dst = rcu_dereference(sk->sk_dst_cache);
1317 if (dst)
1318 dst_hold(dst);
1319 rcu_read_unlock();
1320 return dst;
1323 extern void sk_reset_txq(struct sock *sk);
1325 static inline void dst_negative_advice(struct sock *sk)
1327 struct dst_entry *ndst, *dst = __sk_dst_get(sk);
1329 if (dst && dst->ops->negative_advice) {
1330 ndst = dst->ops->negative_advice(dst);
1332 if (ndst != dst) {
1333 rcu_assign_pointer(sk->sk_dst_cache, ndst);
1334 sk_reset_txq(sk);
1339 static inline void
1340 __sk_dst_set(struct sock *sk, struct dst_entry *dst)
1342 struct dst_entry *old_dst;
1344 sk_tx_queue_clear(sk);
1346 * This can be called while sk is owned by the caller only,
1347 * with no state that can be checked in a rcu_dereference_check() cond
1349 old_dst = rcu_dereference_raw(sk->sk_dst_cache);
1350 rcu_assign_pointer(sk->sk_dst_cache, dst);
1351 dst_release(old_dst);
1354 static inline void
1355 sk_dst_set(struct sock *sk, struct dst_entry *dst)
1357 spin_lock(&sk->sk_dst_lock);
1358 __sk_dst_set(sk, dst);
1359 spin_unlock(&sk->sk_dst_lock);
1362 static inline void
1363 __sk_dst_reset(struct sock *sk)
1365 __sk_dst_set(sk, NULL);
1368 static inline void
1369 sk_dst_reset(struct sock *sk)
1371 spin_lock(&sk->sk_dst_lock);
1372 __sk_dst_reset(sk);
1373 spin_unlock(&sk->sk_dst_lock);
1376 extern struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
1378 extern struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
1380 static inline int sk_can_gso(const struct sock *sk)
1382 return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type);
1385 extern void sk_setup_caps(struct sock *sk, struct dst_entry *dst);
1387 static inline void sk_nocaps_add(struct sock *sk, int flags)
1389 sk->sk_route_nocaps |= flags;
1390 sk->sk_route_caps &= ~flags;
1393 static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
1394 char __user *from, char *to,
1395 int copy, int offset)
1397 if (skb->ip_summed == CHECKSUM_NONE) {
1398 int err = 0;
1399 __wsum csum = csum_and_copy_from_user(from, to, copy, 0, &err);
1400 if (err)
1401 return err;
1402 skb->csum = csum_block_add(skb->csum, csum, offset);
1403 } else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
1404 if (!access_ok(VERIFY_READ, from, copy) ||
1405 __copy_from_user_nocache(to, from, copy))
1406 return -EFAULT;
1407 } else if (copy_from_user(to, from, copy))
1408 return -EFAULT;
1410 return 0;
1413 static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
1414 char __user *from, int copy)
1416 int err, offset = skb->len;
1418 err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy),
1419 copy, offset);
1420 if (err)
1421 __skb_trim(skb, offset);
1423 return err;
1426 static inline int skb_copy_to_page_nocache(struct sock *sk, char __user *from,
1427 struct sk_buff *skb,
1428 struct page *page,
1429 int off, int copy)
1431 int err;
1433 err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off,
1434 copy, skb->len);
1435 if (err)
1436 return err;
1438 skb->len += copy;
1439 skb->data_len += copy;
1440 skb->truesize += copy;
1441 sk->sk_wmem_queued += copy;
1442 sk_mem_charge(sk, copy);
1443 return 0;
1446 static inline int skb_copy_to_page(struct sock *sk, char __user *from,
1447 struct sk_buff *skb, struct page *page,
1448 int off, int copy)
1450 if (skb->ip_summed == CHECKSUM_NONE) {
1451 int err = 0;
1452 __wsum csum = csum_and_copy_from_user(from,
1453 page_address(page) + off,
1454 copy, 0, &err);
1455 if (err)
1456 return err;
1457 skb->csum = csum_block_add(skb->csum, csum, skb->len);
1458 } else if (copy_from_user(page_address(page) + off, from, copy))
1459 return -EFAULT;
1461 skb->len += copy;
1462 skb->data_len += copy;
1463 skb->truesize += copy;
1464 sk->sk_wmem_queued += copy;
1465 sk_mem_charge(sk, copy);
1466 return 0;
1470 * sk_wmem_alloc_get - returns write allocations
1471 * @sk: socket
1473 * Returns sk_wmem_alloc minus initial offset of one
1475 static inline int sk_wmem_alloc_get(const struct sock *sk)
1477 return atomic_read(&sk->sk_wmem_alloc) - 1;
1481 * sk_rmem_alloc_get - returns read allocations
1482 * @sk: socket
1484 * Returns sk_rmem_alloc
1486 static inline int sk_rmem_alloc_get(const struct sock *sk)
1488 return atomic_read(&sk->sk_rmem_alloc);
1492 * sk_has_allocations - check if allocations are outstanding
1493 * @sk: socket
1495 * Returns true if socket has write or read allocations
1497 static inline int sk_has_allocations(const struct sock *sk)
1499 return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk);
1503 * wq_has_sleeper - check if there are any waiting processes
1504 * @wq: struct socket_wq
1506 * Returns true if socket_wq has waiting processes
1508 * The purpose of the wq_has_sleeper and sock_poll_wait is to wrap the memory
1509 * barrier call. They were added due to the race found within the tcp code.
1511 * Consider following tcp code paths:
1513 * CPU1 CPU2
1515 * sys_select receive packet
1516 * ... ...
1517 * __add_wait_queue update tp->rcv_nxt
1518 * ... ...
1519 * tp->rcv_nxt check sock_def_readable
1520 * ... {
1521 * schedule rcu_read_lock();
1522 * wq = rcu_dereference(sk->sk_wq);
1523 * if (wq && waitqueue_active(&wq->wait))
1524 * wake_up_interruptible(&wq->wait)
1525 * ...
1528 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
1529 * in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1
1530 * could then endup calling schedule and sleep forever if there are no more
1531 * data on the socket.
1534 static inline bool wq_has_sleeper(struct socket_wq *wq)
1538 * We need to be sure we are in sync with the
1539 * add_wait_queue modifications to the wait queue.
1541 * This memory barrier is paired in the sock_poll_wait.
1543 smp_mb();
1544 return wq && waitqueue_active(&wq->wait);
1548 * sock_poll_wait - place memory barrier behind the poll_wait call.
1549 * @filp: file
1550 * @wait_address: socket wait queue
1551 * @p: poll_table
1553 * See the comments in the wq_has_sleeper function.
1555 static inline void sock_poll_wait(struct file *filp,
1556 wait_queue_head_t *wait_address, poll_table *p)
1558 if (p && wait_address) {
1559 poll_wait(filp, wait_address, p);
1561 * We need to be sure we are in sync with the
1562 * socket flags modification.
1564 * This memory barrier is paired in the wq_has_sleeper.
1566 smp_mb();
1571 * Queue a received datagram if it will fit. Stream and sequenced
1572 * protocols can't normally use this as they need to fit buffers in
1573 * and play with them.
1575 * Inlined as it's very short and called for pretty much every
1576 * packet ever received.
1579 static inline void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
1581 skb_orphan(skb);
1582 skb->sk = sk;
1583 skb->destructor = sock_wfree;
1585 * We used to take a refcount on sk, but following operation
1586 * is enough to guarantee sk_free() wont free this sock until
1587 * all in-flight packets are completed
1589 atomic_add(skb->truesize, &sk->sk_wmem_alloc);
1592 static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
1594 skb_orphan(skb);
1595 skb->sk = sk;
1596 skb->destructor = sock_rfree;
1597 atomic_add(skb->truesize, &sk->sk_rmem_alloc);
1598 sk_mem_charge(sk, skb->truesize);
1601 extern void sk_reset_timer(struct sock *sk, struct timer_list* timer,
1602 unsigned long expires);
1604 extern void sk_stop_timer(struct sock *sk, struct timer_list* timer);
1606 extern int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
1608 extern int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
1611 * Recover an error report and clear atomically
1614 static inline int sock_error(struct sock *sk)
1616 int err;
1617 if (likely(!sk->sk_err))
1618 return 0;
1619 err = xchg(&sk->sk_err, 0);
1620 return -err;
1623 static inline unsigned long sock_wspace(struct sock *sk)
1625 int amt = 0;
1627 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
1628 amt = sk->sk_sndbuf - atomic_read(&sk->sk_wmem_alloc);
1629 if (amt < 0)
1630 amt = 0;
1632 return amt;
1635 static inline void sk_wake_async(struct sock *sk, int how, int band)
1637 if (sock_flag(sk, SOCK_FASYNC))
1638 sock_wake_async(sk->sk_socket, how, band);
1641 #define SOCK_MIN_SNDBUF 2048
1643 * Since sk_rmem_alloc sums skb->truesize, even a small frame might need
1644 * sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak
1646 #define SOCK_MIN_RCVBUF (2048 + sizeof(struct sk_buff))
1648 static inline void sk_stream_moderate_sndbuf(struct sock *sk)
1650 if (!(sk->sk_userlocks & SOCK_SNDBUF_LOCK)) {
1651 sk->sk_sndbuf = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
1652 sk->sk_sndbuf = max(sk->sk_sndbuf, SOCK_MIN_SNDBUF);
1656 struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp);
1658 static inline struct page *sk_stream_alloc_page(struct sock *sk)
1660 struct page *page = NULL;
1662 page = alloc_pages(sk->sk_allocation, 0);
1663 if (!page) {
1664 sk->sk_prot->enter_memory_pressure(sk);
1665 sk_stream_moderate_sndbuf(sk);
1667 return page;
1671 * Default write policy as shown to user space via poll/select/SIGIO
1673 static inline int sock_writeable(const struct sock *sk)
1675 return atomic_read(&sk->sk_wmem_alloc) < (sk->sk_sndbuf >> 1);
1678 static inline gfp_t gfp_any(void)
1680 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
1683 static inline long sock_rcvtimeo(const struct sock *sk, int noblock)
1685 return noblock ? 0 : sk->sk_rcvtimeo;
1688 static inline long sock_sndtimeo(const struct sock *sk, int noblock)
1690 return noblock ? 0 : sk->sk_sndtimeo;
1693 static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
1695 return (waitall ? len : min_t(int, sk->sk_rcvlowat, len)) ? : 1;
1698 /* Alas, with timeout socket operations are not restartable.
1699 * Compare this to poll().
1701 static inline int sock_intr_errno(long timeo)
1703 return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
1706 extern void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
1707 struct sk_buff *skb);
1709 static __inline__ void
1710 sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
1712 ktime_t kt = skb->tstamp;
1713 struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
1716 * generate control messages if
1717 * - receive time stamping in software requested (SOCK_RCVTSTAMP
1718 * or SOCK_TIMESTAMPING_RX_SOFTWARE)
1719 * - software time stamp available and wanted
1720 * (SOCK_TIMESTAMPING_SOFTWARE)
1721 * - hardware time stamps available and wanted
1722 * (SOCK_TIMESTAMPING_SYS_HARDWARE or
1723 * SOCK_TIMESTAMPING_RAW_HARDWARE)
1725 if (sock_flag(sk, SOCK_RCVTSTAMP) ||
1726 sock_flag(sk, SOCK_TIMESTAMPING_RX_SOFTWARE) ||
1727 (kt.tv64 && sock_flag(sk, SOCK_TIMESTAMPING_SOFTWARE)) ||
1728 (hwtstamps->hwtstamp.tv64 &&
1729 sock_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE)) ||
1730 (hwtstamps->syststamp.tv64 &&
1731 sock_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE)))
1732 __sock_recv_timestamp(msg, sk, skb);
1733 else
1734 sk->sk_stamp = kt;
1737 extern void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
1738 struct sk_buff *skb);
1740 static inline void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
1741 struct sk_buff *skb)
1743 #define FLAGS_TS_OR_DROPS ((1UL << SOCK_RXQ_OVFL) | \
1744 (1UL << SOCK_RCVTSTAMP) | \
1745 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE) | \
1746 (1UL << SOCK_TIMESTAMPING_SOFTWARE) | \
1747 (1UL << SOCK_TIMESTAMPING_RAW_HARDWARE) | \
1748 (1UL << SOCK_TIMESTAMPING_SYS_HARDWARE))
1750 if (sk->sk_flags & FLAGS_TS_OR_DROPS)
1751 __sock_recv_ts_and_drops(msg, sk, skb);
1752 else
1753 sk->sk_stamp = skb->tstamp;
1757 * sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
1758 * @sk: socket sending this packet
1759 * @tx_flags: filled with instructions for time stamping
1761 * Currently only depends on SOCK_TIMESTAMPING* flags. Returns error code if
1762 * parameters are invalid.
1764 extern int sock_tx_timestamp(struct sock *sk, __u8 *tx_flags);
1767 * sk_eat_skb - Release a skb if it is no longer needed
1768 * @sk: socket to eat this skb from
1769 * @skb: socket buffer to eat
1770 * @copied_early: flag indicating whether DMA operations copied this data early
1772 * This routine must be called with interrupts disabled or with the socket
1773 * locked so that the sk_buff queue operation is ok.
1775 #ifdef CONFIG_NET_DMA
1776 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb, int copied_early)
1778 __skb_unlink(skb, &sk->sk_receive_queue);
1779 if (!copied_early)
1780 __kfree_skb(skb);
1781 else
1782 __skb_queue_tail(&sk->sk_async_wait_queue, skb);
1784 #else
1785 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb, int copied_early)
1787 __skb_unlink(skb, &sk->sk_receive_queue);
1788 __kfree_skb(skb);
1790 #endif
1792 static inline
1793 struct net *sock_net(const struct sock *sk)
1795 return read_pnet(&sk->sk_net);
1798 static inline
1799 void sock_net_set(struct sock *sk, struct net *net)
1801 write_pnet(&sk->sk_net, net);
1805 * Kernel sockets, f.e. rtnl or icmp_socket, are a part of a namespace.
1806 * They should not hold a reference to a namespace in order to allow
1807 * to stop it.
1808 * Sockets after sk_change_net should be released using sk_release_kernel
1810 static inline void sk_change_net(struct sock *sk, struct net *net)
1812 put_net(sock_net(sk));
1813 sock_net_set(sk, hold_net(net));
1816 static inline struct sock *skb_steal_sock(struct sk_buff *skb)
1818 if (unlikely(skb->sk)) {
1819 struct sock *sk = skb->sk;
1821 skb->destructor = NULL;
1822 skb->sk = NULL;
1823 return sk;
1825 return NULL;
1828 extern void sock_enable_timestamp(struct sock *sk, int flag);
1829 extern int sock_get_timestamp(struct sock *, struct timeval __user *);
1830 extern int sock_get_timestampns(struct sock *, struct timespec __user *);
1833 * Enable debug/info messages
1835 extern int net_msg_warn;
1836 #define NETDEBUG(fmt, args...) \
1837 do { if (net_msg_warn) printk(fmt,##args); } while (0)
1839 #define LIMIT_NETDEBUG(fmt, args...) \
1840 do { if (net_msg_warn && net_ratelimit()) printk(fmt,##args); } while(0)
1842 extern __u32 sysctl_wmem_max;
1843 extern __u32 sysctl_rmem_max;
1845 extern void sk_init(void);
1847 extern int sysctl_optmem_max;
1849 extern __u32 sysctl_wmem_default;
1850 extern __u32 sysctl_rmem_default;
1852 #endif /* _SOCK_H */