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
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>
16 * Alan Cox : Volatiles in skbuff pointers. See
17 * skbuff comments. May be overdone,
18 * better to prove they can be removed
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.
43 #include <linux/list.h>
44 #include <linux/timer.h>
45 #include <linux/cache.h>
46 #include <linux/module.h>
47 #include <linux/lockdep.h>
48 #include <linux/netdevice.h>
49 #include <linux/skbuff.h> /* struct sk_buff */
51 #include <linux/security.h>
53 #include <linux/filter.h>
55 #include <asm/atomic.h>
57 #include <net/checksum.h>
60 * This structure really needs to be cleaned up.
61 * Most of it is for TCP, and not used by any of
62 * the other protocols.
65 /* Define this to get the SOCK_DBG debugging facility. */
66 #define SOCK_DEBUGGING
68 #define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \
69 printk(KERN_DEBUG msg); } while (0)
71 #define SOCK_DEBUG(sk, msg...) do { } while (0)
74 /* This is the per-socket lock. The spinlock provides a synchronization
75 * between user contexts and software interrupt processing, whereas the
76 * mini-semaphore synchronizes multiple users amongst themselves.
81 struct sock_iocb *owner;
84 * We express the mutex-alike socket_lock semantics
85 * to the lock validator by explicitly managing
86 * the slock as a lock variant (in addition to
89 #ifdef CONFIG_DEBUG_LOCK_ALLOC
90 struct lockdep_map dep_map;
98 * struct sock_common - minimal network layer representation of sockets
99 * @skc_family: network address family
100 * @skc_state: Connection state
101 * @skc_reuse: %SO_REUSEADDR setting
102 * @skc_bound_dev_if: bound device index if != 0
103 * @skc_node: main hash linkage for various protocol lookup tables
104 * @skc_bind_node: bind hash linkage for various protocol lookup tables
105 * @skc_refcnt: reference count
106 * @skc_hash: hash value used with various protocol lookup tables
107 * @skc_prot: protocol handlers inside a network family
109 * This is the minimal network layer representation of sockets, the header
110 * for struct sock and struct inet_timewait_sock.
113 unsigned short skc_family;
114 volatile unsigned char skc_state;
115 unsigned char skc_reuse;
116 int skc_bound_dev_if;
117 struct hlist_node skc_node;
118 struct hlist_node skc_bind_node;
120 unsigned int skc_hash;
121 struct proto *skc_prot;
123 struct vx_info *skc_vx_info;
125 struct nx_info *skc_nx_info;
129 * struct sock - network layer representation of sockets
130 * @__sk_common: shared layout with inet_timewait_sock
131 * @sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
132 * @sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
133 * @sk_lock: synchronizer
134 * @sk_rcvbuf: size of receive buffer in bytes
135 * @sk_sleep: sock wait queue
136 * @sk_dst_cache: destination cache
137 * @sk_dst_lock: destination cache lock
138 * @sk_policy: flow policy
139 * @sk_rmem_alloc: receive queue bytes committed
140 * @sk_receive_queue: incoming packets
141 * @sk_wmem_alloc: transmit queue bytes committed
142 * @sk_write_queue: Packet sending queue
143 * @sk_async_wait_queue: DMA copied packets
144 * @sk_omem_alloc: "o" is "option" or "other"
145 * @sk_wmem_queued: persistent queue size
146 * @sk_forward_alloc: space allocated forward
147 * @sk_allocation: allocation mode
148 * @sk_sndbuf: size of send buffer in bytes
149 * @sk_flags: %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE, %SO_OOBINLINE settings
150 * @sk_no_check: %SO_NO_CHECK setting, wether or not checkup packets
151 * @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
152 * @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
153 * @sk_lingertime: %SO_LINGER l_linger setting
154 * @sk_backlog: always used with the per-socket spinlock held
155 * @sk_callback_lock: used with the callbacks in the end of this struct
156 * @sk_error_queue: rarely used
157 * @sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt, IPV6_ADDRFORM for instance)
158 * @sk_err: last error
159 * @sk_err_soft: errors that don't cause failure but are the cause of a persistent failure not just 'timed out'
160 * @sk_ack_backlog: current listen backlog
161 * @sk_max_ack_backlog: listen backlog set in listen()
162 * @sk_priority: %SO_PRIORITY setting
163 * @sk_type: socket type (%SOCK_STREAM, etc)
164 * @sk_protocol: which protocol this socket belongs in this network family
165 * @sk_peercred: %SO_PEERCRED setting
166 * @sk_rcvlowat: %SO_RCVLOWAT setting
167 * @sk_rcvtimeo: %SO_RCVTIMEO setting
168 * @sk_sndtimeo: %SO_SNDTIMEO setting
169 * @sk_filter: socket filtering instructions
170 * @sk_protinfo: private area, net family specific, when not using slab
171 * @sk_timer: sock cleanup timer
172 * @sk_stamp: time stamp of last packet received
173 * @sk_socket: Identd and reporting IO signals
174 * @sk_user_data: RPC layer private data
175 * @sk_sndmsg_page: cached page for sendmsg
176 * @sk_sndmsg_off: cached offset for sendmsg
177 * @sk_send_head: front of stuff to transmit
178 * @sk_security: used by security modules
179 * @sk_write_pending: a write to stream socket waits to start
180 * @sk_state_change: callback to indicate change in the state of the sock
181 * @sk_data_ready: callback to indicate there is data to be processed
182 * @sk_write_space: callback to indicate there is bf sending space available
183 * @sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
184 * @sk_backlog_rcv: callback to process the backlog
185 * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
189 * Now struct inet_timewait_sock also uses sock_common, so please just
190 * don't add nothing before this first member (__sk_common) --acme
192 struct sock_common __sk_common;
193 #define sk_family __sk_common.skc_family
194 #define sk_state __sk_common.skc_state
195 #define sk_reuse __sk_common.skc_reuse
196 #define sk_bound_dev_if __sk_common.skc_bound_dev_if
197 #define sk_node __sk_common.skc_node
198 #define sk_bind_node __sk_common.skc_bind_node
199 #define sk_refcnt __sk_common.skc_refcnt
200 #define sk_hash __sk_common.skc_hash
201 #define sk_prot __sk_common.skc_prot
202 #define sk_xid __sk_common.skc_xid
203 #define sk_vx_info __sk_common.skc_vx_info
204 #define sk_nid __sk_common.skc_nid
205 #define sk_nx_info __sk_common.skc_nx_info
206 unsigned char sk_shutdown : 2,
209 unsigned char sk_protocol;
210 unsigned short sk_type;
212 socket_lock_t sk_lock;
213 wait_queue_head_t *sk_sleep;
214 struct dst_entry *sk_dst_cache;
215 struct xfrm_policy *sk_policy[2];
216 rwlock_t sk_dst_lock;
217 atomic_t sk_rmem_alloc;
218 atomic_t sk_wmem_alloc;
219 atomic_t sk_omem_alloc;
220 struct sk_buff_head sk_receive_queue;
221 struct sk_buff_head sk_write_queue;
222 struct sk_buff_head sk_async_wait_queue;
224 int sk_forward_alloc;
230 unsigned long sk_flags;
231 unsigned long sk_lingertime;
233 * The backlog queue is special, it is always used with
234 * the per-socket spinlock held and requires low latency
235 * access. Therefore we special case it's implementation.
238 struct sk_buff *head;
239 struct sk_buff *tail;
241 struct sk_buff_head sk_error_queue;
242 struct proto *sk_prot_creator;
243 rwlock_t sk_callback_lock;
246 unsigned short sk_ack_backlog;
247 unsigned short sk_max_ack_backlog;
249 struct ucred sk_peercred;
252 struct sk_filter *sk_filter;
254 struct timer_list sk_timer;
255 struct timeval sk_stamp;
256 struct socket *sk_socket;
258 struct page *sk_sndmsg_page;
259 struct sk_buff *sk_send_head;
261 int sk_write_pending;
263 void (*sk_state_change)(struct sock *sk);
264 void (*sk_data_ready)(struct sock *sk, int bytes);
265 void (*sk_write_space)(struct sock *sk);
266 void (*sk_error_report)(struct sock *sk);
267 int (*sk_backlog_rcv)(struct sock *sk,
268 struct sk_buff *skb);
269 void (*sk_destruct)(struct sock *sk);
273 * Hashed lists helper routines
275 static inline struct sock *__sk_head(const struct hlist_head *head)
277 return hlist_entry(head->first, struct sock, sk_node);
280 static inline struct sock *sk_head(const struct hlist_head *head)
282 return hlist_empty(head) ? NULL : __sk_head(head);
285 static inline struct sock *sk_next(const struct sock *sk)
287 return sk->sk_node.next ?
288 hlist_entry(sk->sk_node.next, struct sock, sk_node) : NULL;
291 static inline int sk_unhashed(const struct sock *sk)
293 return hlist_unhashed(&sk->sk_node);
296 static inline int sk_hashed(const struct sock *sk)
298 return !sk_unhashed(sk);
301 static __inline__ void sk_node_init(struct hlist_node *node)
306 static __inline__ void __sk_del_node(struct sock *sk)
308 __hlist_del(&sk->sk_node);
311 static __inline__ int __sk_del_node_init(struct sock *sk)
315 sk_node_init(&sk->sk_node);
321 /* Grab socket reference count. This operation is valid only
322 when sk is ALREADY grabbed f.e. it is found in hash table
323 or a list and the lookup is made under lock preventing hash table
327 static inline void sock_hold(struct sock *sk)
329 atomic_inc(&sk->sk_refcnt);
332 /* Ungrab socket in the context, which assumes that socket refcnt
333 cannot hit zero, f.e. it is true in context of any socketcall.
335 static inline void __sock_put(struct sock *sk)
337 atomic_dec(&sk->sk_refcnt);
340 static __inline__ int sk_del_node_init(struct sock *sk)
342 int rc = __sk_del_node_init(sk);
345 /* paranoid for a while -acme */
346 WARN_ON(atomic_read(&sk->sk_refcnt) == 1);
352 static __inline__ void __sk_add_node(struct sock *sk, struct hlist_head *list)
354 hlist_add_head(&sk->sk_node, list);
357 static __inline__ void sk_add_node(struct sock *sk, struct hlist_head *list)
360 __sk_add_node(sk, list);
363 static __inline__ void __sk_del_bind_node(struct sock *sk)
365 __hlist_del(&sk->sk_bind_node);
368 static __inline__ void sk_add_bind_node(struct sock *sk,
369 struct hlist_head *list)
371 hlist_add_head(&sk->sk_bind_node, list);
374 #define sk_for_each(__sk, node, list) \
375 hlist_for_each_entry(__sk, node, list, sk_node)
376 #define sk_for_each_from(__sk, node) \
377 if (__sk && ({ node = &(__sk)->sk_node; 1; })) \
378 hlist_for_each_entry_from(__sk, node, sk_node)
379 #define sk_for_each_continue(__sk, node) \
380 if (__sk && ({ node = &(__sk)->sk_node; 1; })) \
381 hlist_for_each_entry_continue(__sk, node, sk_node)
382 #define sk_for_each_safe(__sk, node, tmp, list) \
383 hlist_for_each_entry_safe(__sk, node, tmp, list, sk_node)
384 #define sk_for_each_bound(__sk, node, list) \
385 hlist_for_each_entry(__sk, node, list, sk_bind_node)
398 SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */
399 SOCK_DBG, /* %SO_DEBUG setting */
400 SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
401 SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
402 SOCK_QUEUE_SHRUNK, /* write queue has been shrunk recently */
405 static inline void sock_copy_flags(struct sock *nsk, struct sock *osk)
407 nsk->sk_flags = osk->sk_flags;
410 static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
412 __set_bit(flag, &sk->sk_flags);
415 static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag)
417 __clear_bit(flag, &sk->sk_flags);
420 static inline int sock_flag(struct sock *sk, enum sock_flags flag)
422 return test_bit(flag, &sk->sk_flags);
425 static inline void sk_acceptq_removed(struct sock *sk)
427 sk->sk_ack_backlog--;
430 static inline void sk_acceptq_added(struct sock *sk)
432 sk->sk_ack_backlog++;
435 static inline int sk_acceptq_is_full(struct sock *sk)
437 return sk->sk_ack_backlog > sk->sk_max_ack_backlog;
441 * Compute minimal free write space needed to queue new packets.
443 static inline int sk_stream_min_wspace(struct sock *sk)
445 return sk->sk_wmem_queued / 2;
448 static inline int sk_stream_wspace(struct sock *sk)
450 return sk->sk_sndbuf - sk->sk_wmem_queued;
453 extern void sk_stream_write_space(struct sock *sk);
455 static inline int sk_stream_memory_free(struct sock *sk)
457 return sk->sk_wmem_queued < sk->sk_sndbuf;
460 extern void sk_stream_rfree(struct sk_buff *skb);
462 static inline void sk_stream_set_owner_r(struct sk_buff *skb, struct sock *sk)
465 skb->destructor = sk_stream_rfree;
466 atomic_add(skb->truesize, &sk->sk_rmem_alloc);
467 sk->sk_forward_alloc -= skb->truesize;
470 static inline void sk_stream_free_skb(struct sock *sk, struct sk_buff *skb)
472 skb_truesize_check(skb);
473 sock_set_flag(sk, SOCK_QUEUE_SHRUNK);
474 sk->sk_wmem_queued -= skb->truesize;
475 sk->sk_forward_alloc += skb->truesize;
479 /* The per-socket spinlock must be held here. */
480 static inline void sk_add_backlog(struct sock *sk, struct sk_buff *skb)
482 if (!sk->sk_backlog.tail) {
483 sk->sk_backlog.head = sk->sk_backlog.tail = skb;
485 sk->sk_backlog.tail->next = skb;
486 sk->sk_backlog.tail = skb;
491 #define sk_wait_event(__sk, __timeo, __condition) \
493 release_sock(__sk); \
496 *(__timeo) = schedule_timeout(*(__timeo)); \
503 extern int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
504 extern int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
505 extern void sk_stream_wait_close(struct sock *sk, long timeo_p);
506 extern int sk_stream_error(struct sock *sk, int flags, int err);
507 extern void sk_stream_kill_queues(struct sock *sk);
509 extern int sk_wait_data(struct sock *sk, long *timeo);
511 struct request_sock_ops;
512 struct timewait_sock_ops;
514 /* Networking protocol blocks we attach to sockets.
515 * socket layer -> transport layer interface
516 * transport -> network interface is defined by struct inet_proto
519 void (*close)(struct sock *sk,
521 int (*connect)(struct sock *sk,
522 struct sockaddr *uaddr,
524 int (*disconnect)(struct sock *sk, int flags);
526 struct sock * (*accept) (struct sock *sk, int flags, int *err);
528 int (*ioctl)(struct sock *sk, int cmd,
530 int (*init)(struct sock *sk);
531 int (*destroy)(struct sock *sk);
532 void (*shutdown)(struct sock *sk, int how);
533 int (*setsockopt)(struct sock *sk, int level,
534 int optname, char __user *optval,
536 int (*getsockopt)(struct sock *sk, int level,
537 int optname, char __user *optval,
539 int (*compat_setsockopt)(struct sock *sk,
541 int optname, char __user *optval,
543 int (*compat_getsockopt)(struct sock *sk,
545 int optname, char __user *optval,
547 int (*sendmsg)(struct kiocb *iocb, struct sock *sk,
548 struct msghdr *msg, size_t len);
549 int (*recvmsg)(struct kiocb *iocb, struct sock *sk,
551 size_t len, int noblock, int flags,
553 int (*sendpage)(struct sock *sk, struct page *page,
554 int offset, size_t size, int flags);
555 int (*bind)(struct sock *sk,
556 struct sockaddr *uaddr, int addr_len);
558 int (*backlog_rcv) (struct sock *sk,
559 struct sk_buff *skb);
561 /* Keeping track of sk's, looking them up, and port selection methods. */
562 void (*hash)(struct sock *sk);
563 void (*unhash)(struct sock *sk);
564 int (*get_port)(struct sock *sk, unsigned short snum);
566 /* Memory pressure */
567 void (*enter_memory_pressure)(void);
568 atomic_t *memory_allocated; /* Current allocated memory. */
569 atomic_t *sockets_allocated; /* Current number of sockets. */
571 * Pressure flag: try to collapse.
572 * Technical note: it is used by multiple contexts non atomically.
573 * All the sk_stream_mem_schedule() is of this nature: accounting
574 * is strict, actions are advisory and have some latency.
576 int *memory_pressure;
582 struct kmem_cache *slab;
583 unsigned int obj_size;
585 atomic_t *orphan_count;
587 struct request_sock_ops *rsk_prot;
588 struct timewait_sock_ops *twsk_prot;
590 struct module *owner;
594 struct list_head node;
595 #ifdef SOCK_REFCNT_DEBUG
600 u8 __pad[SMP_CACHE_BYTES - sizeof(int)];
604 extern int proto_register(struct proto *prot, int alloc_slab);
605 extern void proto_unregister(struct proto *prot);
607 #ifdef SOCK_REFCNT_DEBUG
608 static inline void sk_refcnt_debug_inc(struct sock *sk)
610 atomic_inc(&sk->sk_prot->socks);
613 static inline void sk_refcnt_debug_dec(struct sock *sk)
615 atomic_dec(&sk->sk_prot->socks);
616 printk(KERN_DEBUG "%s socket %p released, %d are still alive\n",
617 sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks));
620 static inline void sk_refcnt_debug_release(const struct sock *sk)
622 if (atomic_read(&sk->sk_refcnt) != 1)
623 printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n",
624 sk->sk_prot->name, sk, atomic_read(&sk->sk_refcnt));
626 #else /* SOCK_REFCNT_DEBUG */
627 #define sk_refcnt_debug_inc(sk) do { } while (0)
628 #define sk_refcnt_debug_dec(sk) do { } while (0)
629 #define sk_refcnt_debug_release(sk) do { } while (0)
630 #endif /* SOCK_REFCNT_DEBUG */
632 /* Called with local bh disabled */
633 static __inline__ void sock_prot_inc_use(struct proto *prot)
635 prot->stats[smp_processor_id()].inuse++;
638 static __inline__ void sock_prot_dec_use(struct proto *prot)
640 prot->stats[smp_processor_id()].inuse--;
643 /* With per-bucket locks this operation is not-atomic, so that
644 * this version is not worse.
646 static inline void __sk_prot_rehash(struct sock *sk)
648 sk->sk_prot->unhash(sk);
649 sk->sk_prot->hash(sk);
652 /* About 10 seconds */
653 #define SOCK_DESTROY_TIME (10*HZ)
655 /* Sockets 0-1023 can't be bound to unless you are superuser */
656 #define PROT_SOCK 1024
658 #define SHUTDOWN_MASK 3
659 #define RCV_SHUTDOWN 1
660 #define SEND_SHUTDOWN 2
662 #define SOCK_SNDBUF_LOCK 1
663 #define SOCK_RCVBUF_LOCK 2
664 #define SOCK_BINDADDR_LOCK 4
665 #define SOCK_BINDPORT_LOCK 8
667 /* sock_iocb: used to kick off async processing of socket ios */
669 struct list_head list;
675 struct scm_cookie *scm;
676 struct msghdr *msg, async_msg;
680 static inline struct sock_iocb *kiocb_to_siocb(struct kiocb *iocb)
682 return (struct sock_iocb *)iocb->private;
685 static inline struct kiocb *siocb_to_kiocb(struct sock_iocb *si)
690 struct socket_alloc {
691 struct socket socket;
692 struct inode vfs_inode;
695 static inline struct socket *SOCKET_I(struct inode *inode)
697 return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
700 static inline struct inode *SOCK_INODE(struct socket *socket)
702 return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
705 extern void __sk_stream_mem_reclaim(struct sock *sk);
706 extern int sk_stream_mem_schedule(struct sock *sk, int size, int kind);
708 #define SK_STREAM_MEM_QUANTUM ((int)PAGE_SIZE)
710 static inline int sk_stream_pages(int amt)
712 return (amt + SK_STREAM_MEM_QUANTUM - 1) / SK_STREAM_MEM_QUANTUM;
715 static inline void sk_stream_mem_reclaim(struct sock *sk)
717 if (sk->sk_forward_alloc >= SK_STREAM_MEM_QUANTUM)
718 __sk_stream_mem_reclaim(sk);
721 static inline void sk_stream_writequeue_purge(struct sock *sk)
725 while ((skb = __skb_dequeue(&sk->sk_write_queue)) != NULL)
726 sk_stream_free_skb(sk, skb);
727 sk_stream_mem_reclaim(sk);
730 static inline int sk_stream_rmem_schedule(struct sock *sk, struct sk_buff *skb)
732 return (int)skb->truesize <= sk->sk_forward_alloc ||
733 sk_stream_mem_schedule(sk, skb->truesize, 1);
736 static inline int sk_stream_wmem_schedule(struct sock *sk, int size)
738 return size <= sk->sk_forward_alloc ||
739 sk_stream_mem_schedule(sk, size, 0);
742 /* Used by processes to "lock" a socket state, so that
743 * interrupts and bottom half handlers won't change it
744 * from under us. It essentially blocks any incoming
745 * packets, so that we won't get any new data or any
746 * packets that change the state of the socket.
748 * While locked, BH processing will add new packets to
749 * the backlog queue. This queue is processed by the
750 * owner of the socket lock right before it is released.
752 * Since ~2.3.5 it is also exclusive sleep lock serializing
753 * accesses from user process context.
755 #define sock_owned_by_user(sk) ((sk)->sk_lock.owner)
758 * Macro so as to not evaluate some arguments when
759 * lockdep is not enabled.
761 * Mark both the sk_lock and the sk_lock.slock as a
762 * per-address-family lock class.
764 #define sock_lock_init_class_and_name(sk, sname, skey, name, key) \
766 sk->sk_lock.owner = NULL; \
767 init_waitqueue_head(&sk->sk_lock.wq); \
768 spin_lock_init(&(sk)->sk_lock.slock); \
769 debug_check_no_locks_freed((void *)&(sk)->sk_lock, \
770 sizeof((sk)->sk_lock)); \
771 lockdep_set_class_and_name(&(sk)->sk_lock.slock, \
773 lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \
776 extern void FASTCALL(lock_sock_nested(struct sock *sk, int subclass));
778 static inline void lock_sock(struct sock *sk)
780 lock_sock_nested(sk, 0);
783 extern void FASTCALL(release_sock(struct sock *sk));
785 /* BH context may only use the following locking interface. */
786 #define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock))
787 #define bh_lock_sock_nested(__sk) \
788 spin_lock_nested(&((__sk)->sk_lock.slock), \
789 SINGLE_DEPTH_NESTING)
790 #define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock))
792 extern struct sock *sk_alloc(int family,
794 struct proto *prot, int zero_it);
795 extern void sk_free(struct sock *sk);
796 extern struct sock *sk_clone(const struct sock *sk,
797 const gfp_t priority);
799 extern struct sk_buff *sock_wmalloc(struct sock *sk,
800 unsigned long size, int force,
802 extern struct sk_buff *sock_rmalloc(struct sock *sk,
803 unsigned long size, int force,
805 extern void sock_wfree(struct sk_buff *skb);
806 extern void sock_rfree(struct sk_buff *skb);
808 extern int sock_setsockopt(struct socket *sock, int level,
809 int op, char __user *optval,
812 extern int sock_getsockopt(struct socket *sock, int level,
813 int op, char __user *optval,
815 extern struct sk_buff *sock_alloc_send_skb(struct sock *sk,
819 extern void *sock_kmalloc(struct sock *sk, int size,
821 extern void sock_kfree_s(struct sock *sk, void *mem, int size);
822 extern void sk_send_sigurg(struct sock *sk);
825 * Functions to fill in entries in struct proto_ops when a protocol
826 * does not implement a particular function.
828 extern int sock_no_bind(struct socket *,
829 struct sockaddr *, int);
830 extern int sock_no_connect(struct socket *,
831 struct sockaddr *, int, int);
832 extern int sock_no_socketpair(struct socket *,
834 extern int sock_no_accept(struct socket *,
835 struct socket *, int);
836 extern int sock_no_getname(struct socket *,
837 struct sockaddr *, int *, int);
838 extern unsigned int sock_no_poll(struct file *, struct socket *,
839 struct poll_table_struct *);
840 extern int sock_no_ioctl(struct socket *, unsigned int,
842 extern int sock_no_listen(struct socket *, int);
843 extern int sock_no_shutdown(struct socket *, int);
844 extern int sock_no_getsockopt(struct socket *, int , int,
845 char __user *, int __user *);
846 extern int sock_no_setsockopt(struct socket *, int, int,
848 extern int sock_no_sendmsg(struct kiocb *, struct socket *,
849 struct msghdr *, size_t);
850 extern int sock_no_recvmsg(struct kiocb *, struct socket *,
851 struct msghdr *, size_t, int);
852 extern int sock_no_mmap(struct file *file,
854 struct vm_area_struct *vma);
855 extern ssize_t sock_no_sendpage(struct socket *sock,
857 int offset, size_t size,
861 * Functions to fill in entries in struct proto_ops when a protocol
862 * uses the inet style.
864 extern int sock_common_getsockopt(struct socket *sock, int level, int optname,
865 char __user *optval, int __user *optlen);
866 extern int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock,
867 struct msghdr *msg, size_t size, int flags);
868 extern int sock_common_setsockopt(struct socket *sock, int level, int optname,
869 char __user *optval, int optlen);
870 extern int compat_sock_common_getsockopt(struct socket *sock, int level,
871 int optname, char __user *optval, int __user *optlen);
872 extern int compat_sock_common_setsockopt(struct socket *sock, int level,
873 int optname, char __user *optval, int optlen);
875 extern void sk_common_release(struct sock *sk);
878 * Default socket callbacks and setup code
881 /* Initialise core socket variables */
882 extern void sock_init_data(struct socket *sock, struct sock *sk);
885 * sk_filter - run a packet through a socket filter
886 * @sk: sock associated with &sk_buff
887 * @skb: buffer to filter
888 * @needlock: set to 1 if the sock is not locked by caller.
890 * Run the filter code and then cut skb->data to correct size returned by
891 * sk_run_filter. If pkt_len is 0 we toss packet. If skb->len is smaller
892 * than pkt_len we keep whole skb->data. This is the socket level
893 * wrapper to sk_run_filter. It returns 0 if the packet should
894 * be accepted or -EPERM if the packet should be tossed.
898 static inline int sk_filter(struct sock *sk, struct sk_buff *skb)
901 struct sk_filter *filter;
903 err = security_sock_rcv_skb(sk, skb);
908 filter = sk->sk_filter;
910 unsigned int pkt_len = sk_run_filter(skb, filter->insns,
912 err = pkt_len ? pskb_trim(skb, pkt_len) : -EPERM;
914 rcu_read_unlock_bh();
920 * sk_filter_rcu_free: Free a socket filter
921 * @rcu: rcu_head that contains the sk_filter to free
923 static inline void sk_filter_rcu_free(struct rcu_head *rcu)
925 struct sk_filter *fp = container_of(rcu, struct sk_filter, rcu);
930 * sk_filter_release: Release a socket filter
932 * @fp: filter to remove
934 * Remove a filter from a socket and release its resources.
937 static inline void sk_filter_release(struct sock *sk, struct sk_filter *fp)
939 unsigned int size = sk_filter_len(fp);
941 atomic_sub(size, &sk->sk_omem_alloc);
943 if (atomic_dec_and_test(&fp->refcnt))
944 call_rcu_bh(&fp->rcu, sk_filter_rcu_free);
947 static inline void sk_filter_charge(struct sock *sk, struct sk_filter *fp)
949 atomic_inc(&fp->refcnt);
950 atomic_add(sk_filter_len(fp), &sk->sk_omem_alloc);
954 * Socket reference counting postulates.
956 * * Each user of socket SHOULD hold a reference count.
957 * * Each access point to socket (an hash table bucket, reference from a list,
958 * running timer, skb in flight MUST hold a reference count.
959 * * When reference count hits 0, it means it will never increase back.
960 * * When reference count hits 0, it means that no references from
961 * outside exist to this socket and current process on current CPU
962 * is last user and may/should destroy this socket.
963 * * sk_free is called from any context: process, BH, IRQ. When
964 * it is called, socket has no references from outside -> sk_free
965 * may release descendant resources allocated by the socket, but
966 * to the time when it is called, socket is NOT referenced by any
967 * hash tables, lists etc.
968 * * Packets, delivered from outside (from network or from another process)
969 * and enqueued on receive/error queues SHOULD NOT grab reference count,
970 * when they sit in queue. Otherwise, packets will leak to hole, when
971 * socket is looked up by one cpu and unhasing is made by another CPU.
972 * It is true for udp/raw, netlink (leak to receive and error queues), tcp
973 * (leak to backlog). Packet socket does all the processing inside
974 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
975 * use separate SMP lock, so that they are prone too.
978 /* Ungrab socket and destroy it, if it was the last reference. */
979 static inline void sock_put(struct sock *sk)
981 if (atomic_dec_and_test(&sk->sk_refcnt))
985 extern int sk_receive_skb(struct sock *sk, struct sk_buff *skb,
988 /* Detach socket from process context.
989 * Announce socket dead, detach it from wait queue and inode.
990 * Note that parent inode held reference count on this struct sock,
991 * we do not release it in this function, because protocol
992 * probably wants some additional cleanups or even continuing
993 * to work with this socket (TCP).
995 static inline void sock_orphan(struct sock *sk)
997 write_lock_bh(&sk->sk_callback_lock);
998 sock_set_flag(sk, SOCK_DEAD);
999 sk->sk_socket = NULL;
1000 sk->sk_sleep = NULL;
1001 write_unlock_bh(&sk->sk_callback_lock);
1004 static inline void sock_graft(struct sock *sk, struct socket *parent)
1006 write_lock_bh(&sk->sk_callback_lock);
1007 sk->sk_sleep = &parent->wait;
1009 sk->sk_socket = parent;
1010 security_sock_graft(sk, parent);
1011 write_unlock_bh(&sk->sk_callback_lock);
1014 static inline void sock_copy(struct sock *nsk, const struct sock *osk)
1016 #ifdef CONFIG_SECURITY_NETWORK
1017 void *sptr = nsk->sk_security;
1020 memcpy(nsk, osk, osk->sk_prot->obj_size);
1021 #ifdef CONFIG_SECURITY_NETWORK
1022 nsk->sk_security = sptr;
1023 security_sk_clone(osk, nsk);
1027 extern int sock_i_uid(struct sock *sk);
1028 extern unsigned long sock_i_ino(struct sock *sk);
1030 static inline struct dst_entry *
1031 __sk_dst_get(struct sock *sk)
1033 return sk->sk_dst_cache;
1036 static inline struct dst_entry *
1037 sk_dst_get(struct sock *sk)
1039 struct dst_entry *dst;
1041 read_lock(&sk->sk_dst_lock);
1042 dst = sk->sk_dst_cache;
1045 read_unlock(&sk->sk_dst_lock);
1050 __sk_dst_set(struct sock *sk, struct dst_entry *dst)
1052 struct dst_entry *old_dst;
1054 old_dst = sk->sk_dst_cache;
1055 sk->sk_dst_cache = dst;
1056 dst_release(old_dst);
1060 sk_dst_set(struct sock *sk, struct dst_entry *dst)
1062 write_lock(&sk->sk_dst_lock);
1063 __sk_dst_set(sk, dst);
1064 write_unlock(&sk->sk_dst_lock);
1068 __sk_dst_reset(struct sock *sk)
1070 struct dst_entry *old_dst;
1072 old_dst = sk->sk_dst_cache;
1073 sk->sk_dst_cache = NULL;
1074 dst_release(old_dst);
1078 sk_dst_reset(struct sock *sk)
1080 write_lock(&sk->sk_dst_lock);
1082 write_unlock(&sk->sk_dst_lock);
1085 extern struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
1087 extern struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
1089 static inline int sk_can_gso(const struct sock *sk)
1091 return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type);
1094 static inline void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
1096 __sk_dst_set(sk, dst);
1097 sk->sk_route_caps = dst->dev->features;
1098 if (sk->sk_route_caps & NETIF_F_GSO)
1099 sk->sk_route_caps |= NETIF_F_GSO_MASK;
1100 if (sk_can_gso(sk)) {
1101 if (dst->header_len)
1102 sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
1104 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
1108 static inline void sk_charge_skb(struct sock *sk, struct sk_buff *skb)
1110 sk->sk_wmem_queued += skb->truesize;
1111 sk->sk_forward_alloc -= skb->truesize;
1114 static inline int skb_copy_to_page(struct sock *sk, char __user *from,
1115 struct sk_buff *skb, struct page *page,
1118 if (skb->ip_summed == CHECKSUM_NONE) {
1120 __wsum csum = csum_and_copy_from_user(from,
1121 page_address(page) + off,
1125 skb->csum = csum_block_add(skb->csum, csum, skb->len);
1126 } else if (copy_from_user(page_address(page) + off, from, copy))
1130 skb->data_len += copy;
1131 skb->truesize += copy;
1132 sk->sk_wmem_queued += copy;
1133 sk->sk_forward_alloc -= copy;
1138 * Queue a received datagram if it will fit. Stream and sequenced
1139 * protocols can't normally use this as they need to fit buffers in
1140 * and play with them.
1142 * Inlined as it's very short and called for pretty much every
1143 * packet ever received.
1146 static inline void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
1150 skb->destructor = sock_wfree;
1151 atomic_add(skb->truesize, &sk->sk_wmem_alloc);
1154 static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
1157 skb->destructor = sock_rfree;
1158 atomic_add(skb->truesize, &sk->sk_rmem_alloc);
1161 extern void sk_reset_timer(struct sock *sk, struct timer_list* timer,
1162 unsigned long expires);
1164 extern void sk_stop_timer(struct sock *sk, struct timer_list* timer);
1166 extern int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
1168 static inline int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb)
1170 /* Cast skb->rcvbuf to unsigned... It's pointless, but reduces
1171 number of warnings when compiling with -W --ANK
1173 if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >=
1174 (unsigned)sk->sk_rcvbuf)
1176 skb_set_owner_r(skb, sk);
1177 skb_queue_tail(&sk->sk_error_queue, skb);
1178 if (!sock_flag(sk, SOCK_DEAD))
1179 sk->sk_data_ready(sk, skb->len);
1184 * Recover an error report and clear atomically
1187 static inline int sock_error(struct sock *sk)
1190 if (likely(!sk->sk_err))
1192 err = xchg(&sk->sk_err, 0);
1196 static inline unsigned long sock_wspace(struct sock *sk)
1200 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
1201 amt = sk->sk_sndbuf - atomic_read(&sk->sk_wmem_alloc);
1208 static inline void sk_wake_async(struct sock *sk, int how, int band)
1210 if (sk->sk_socket && sk->sk_socket->fasync_list)
1211 sock_wake_async(sk->sk_socket, how, band);
1214 #define SOCK_MIN_SNDBUF 2048
1215 #define SOCK_MIN_RCVBUF 256
1217 static inline void sk_stream_moderate_sndbuf(struct sock *sk)
1219 if (!(sk->sk_userlocks & SOCK_SNDBUF_LOCK)) {
1220 sk->sk_sndbuf = min(sk->sk_sndbuf, sk->sk_wmem_queued / 2);
1221 sk->sk_sndbuf = max(sk->sk_sndbuf, SOCK_MIN_SNDBUF);
1225 static inline struct sk_buff *sk_stream_alloc_pskb(struct sock *sk,
1229 struct sk_buff *skb;
1232 hdr_len = SKB_DATA_ALIGN(sk->sk_prot->max_header);
1233 skb = alloc_skb_fclone(size + hdr_len, gfp);
1235 skb->truesize += mem;
1236 if (sk_stream_wmem_schedule(sk, skb->truesize)) {
1237 skb_reserve(skb, hdr_len);
1242 sk->sk_prot->enter_memory_pressure();
1243 sk_stream_moderate_sndbuf(sk);
1248 static inline struct sk_buff *sk_stream_alloc_skb(struct sock *sk,
1252 return sk_stream_alloc_pskb(sk, size, 0, gfp);
1255 static inline struct page *sk_stream_alloc_page(struct sock *sk)
1257 struct page *page = NULL;
1259 page = alloc_pages(sk->sk_allocation, 0);
1261 sk->sk_prot->enter_memory_pressure();
1262 sk_stream_moderate_sndbuf(sk);
1267 #define sk_stream_for_retrans_queue(skb, sk) \
1268 for (skb = (sk)->sk_write_queue.next; \
1269 (skb != (sk)->sk_send_head) && \
1270 (skb != (struct sk_buff *)&(sk)->sk_write_queue); \
1273 /*from STCP for fast SACK Process*/
1274 #define sk_stream_for_retrans_queue_from(skb, sk) \
1275 for (; (skb != (sk)->sk_send_head) && \
1276 (skb != (struct sk_buff *)&(sk)->sk_write_queue); \
1280 * Default write policy as shown to user space via poll/select/SIGIO
1282 static inline int sock_writeable(const struct sock *sk)
1284 return atomic_read(&sk->sk_wmem_alloc) < (sk->sk_sndbuf / 2);
1287 static inline gfp_t gfp_any(void)
1289 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
1292 static inline long sock_rcvtimeo(const struct sock *sk, int noblock)
1294 return noblock ? 0 : sk->sk_rcvtimeo;
1297 static inline long sock_sndtimeo(const struct sock *sk, int noblock)
1299 return noblock ? 0 : sk->sk_sndtimeo;
1302 static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
1304 return (waitall ? len : min_t(int, sk->sk_rcvlowat, len)) ? : 1;
1307 /* Alas, with timeout socket operations are not restartable.
1308 * Compare this to poll().
1310 static inline int sock_intr_errno(long timeo)
1312 return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
1315 static __inline__ void
1316 sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
1318 struct timeval stamp;
1320 skb_get_timestamp(skb, &stamp);
1321 if (sock_flag(sk, SOCK_RCVTSTAMP)) {
1322 /* Race occurred between timestamp enabling and packet
1323 receiving. Fill in the current time for now. */
1324 if (stamp.tv_sec == 0)
1325 do_gettimeofday(&stamp);
1326 skb_set_timestamp(skb, &stamp);
1327 put_cmsg(msg, SOL_SOCKET, SO_TIMESTAMP, sizeof(struct timeval),
1330 sk->sk_stamp = stamp;
1334 * sk_eat_skb - Release a skb if it is no longer needed
1335 * @sk: socket to eat this skb from
1336 * @skb: socket buffer to eat
1337 * @copied_early: flag indicating whether DMA operations copied this data early
1339 * This routine must be called with interrupts disabled or with the socket
1340 * locked so that the sk_buff queue operation is ok.
1342 #ifdef CONFIG_NET_DMA
1343 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb, int copied_early)
1345 __skb_unlink(skb, &sk->sk_receive_queue);
1349 __skb_queue_tail(&sk->sk_async_wait_queue, skb);
1352 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb, int copied_early)
1354 __skb_unlink(skb, &sk->sk_receive_queue);
1359 extern void sock_enable_timestamp(struct sock *sk);
1360 extern int sock_get_timestamp(struct sock *, struct timeval __user *);
1363 * Enable debug/info messages
1366 #ifdef CONFIG_NETDEBUG
1367 #define NETDEBUG(fmt, args...) printk(fmt,##args)
1368 #define LIMIT_NETDEBUG(fmt, args...) do { if (net_ratelimit()) printk(fmt,##args); } while(0)
1370 #define NETDEBUG(fmt, args...) do { } while (0)
1371 #define LIMIT_NETDEBUG(fmt, args...) do { } while(0)
1375 * Macros for sleeping on a socket. Use them like this:
1377 * SOCK_SLEEP_PRE(sk)
1380 * SOCK_SLEEP_POST(sk)
1382 * N.B. These are now obsolete and were, afaik, only ever used in DECnet
1383 * and when the last use of them in DECnet has gone, I'm intending to
1387 #define SOCK_SLEEP_PRE(sk) { struct task_struct *tsk = current; \
1388 DECLARE_WAITQUEUE(wait, tsk); \
1389 tsk->state = TASK_INTERRUPTIBLE; \
1390 add_wait_queue((sk)->sk_sleep, &wait); \
1393 #define SOCK_SLEEP_POST(sk) tsk->state = TASK_RUNNING; \
1394 remove_wait_queue((sk)->sk_sleep, &wait); \
1398 static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool)
1401 sock_set_flag(sk, bit);
1403 sock_reset_flag(sk, bit);
1406 extern __u32 sysctl_wmem_max;
1407 extern __u32 sysctl_rmem_max;
1410 int siocdevprivate_ioctl(unsigned int fd, unsigned int cmd, unsigned long arg);
1412 static inline int siocdevprivate_ioctl(unsigned int fd, unsigned int cmd, unsigned long arg)
1418 extern void sk_init(void);
1420 #ifdef CONFIG_SYSCTL
1421 extern struct ctl_table core_table[];
1424 extern int sysctl_optmem_max;
1426 extern __u32 sysctl_wmem_default;
1427 extern __u32 sysctl_rmem_default;
1429 #endif /* _SOCK_H */