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/config.h>
44 #include <linux/list.h>
45 #include <linux/timer.h>
46 #include <linux/cache.h>
47 #include <linux/module.h>
48 #include <linux/netdevice.h>
49 #include <linux/skbuff.h> /* struct sk_buff */
50 #include <linux/security.h>
52 #include <linux/filter.h>
54 #include <asm/atomic.h>
56 #include <net/checksum.h>
59 * This structure really needs to be cleaned up.
60 * Most of it is for TCP, and not used by any of
61 * the other protocols.
64 /* Define this to get the SOCK_DBG debugging facility. */
65 #define SOCK_DEBUGGING
67 #define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \
68 printk(KERN_DEBUG msg); } while (0)
70 #define SOCK_DEBUG(sk, msg...) do { } while (0)
73 /* This is the per-socket lock. The spinlock provides a synchronization
74 * between user contexts and software interrupt processing, whereas the
75 * mini-semaphore synchronizes multiple users amongst themselves.
80 struct sock_iocb
*owner
;
84 #define sock_lock_init(__sk) \
85 do { spin_lock_init(&((__sk)->sk_lock.slock)); \
86 (__sk)->sk_lock.owner = NULL; \
87 init_waitqueue_head(&((__sk)->sk_lock.wq)); \
93 * struct sock_common - minimal network layer representation of sockets
94 * @skc_family: network address family
95 * @skc_state: Connection state
96 * @skc_reuse: %SO_REUSEADDR setting
97 * @skc_bound_dev_if: bound device index if != 0
98 * @skc_node: main hash linkage for various protocol lookup tables
99 * @skc_bind_node: bind hash linkage for various protocol lookup tables
100 * @skc_refcnt: reference count
102 * This is the minimal network layer representation of sockets, the header
103 * for struct sock and struct tcp_tw_bucket.
106 unsigned short skc_family
;
107 volatile unsigned char skc_state
;
108 unsigned char skc_reuse
;
109 int skc_bound_dev_if
;
110 struct hlist_node skc_node
;
111 struct hlist_node skc_bind_node
;
116 * struct sock - network layer representation of sockets
117 * @__sk_common: shared layout with tcp_tw_bucket
118 * @sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
119 * @sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
120 * @sk_lock: synchronizer
121 * @sk_rcvbuf: size of receive buffer in bytes
122 * @sk_sleep: sock wait queue
123 * @sk_dst_cache: destination cache
124 * @sk_dst_lock: destination cache lock
125 * @sk_policy: flow policy
126 * @sk_rmem_alloc: receive queue bytes committed
127 * @sk_receive_queue: incoming packets
128 * @sk_wmem_alloc: transmit queue bytes committed
129 * @sk_write_queue: Packet sending queue
130 * @sk_omem_alloc: "o" is "option" or "other"
131 * @sk_wmem_queued: persistent queue size
132 * @sk_forward_alloc: space allocated forward
133 * @sk_allocation: allocation mode
134 * @sk_sndbuf: size of send buffer in bytes
135 * @sk_flags: %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE, %SO_OOBINLINE settings
136 * @sk_no_check: %SO_NO_CHECK setting, wether or not checkup packets
137 * @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
138 * @sk_lingertime: %SO_LINGER l_linger setting
139 * @sk_hashent: hash entry in several tables (e.g. tcp_ehash)
140 * @sk_backlog: always used with the per-socket spinlock held
141 * @sk_callback_lock: used with the callbacks in the end of this struct
142 * @sk_error_queue: rarely used
143 * @sk_prot: protocol handlers inside a network family
144 * @sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt, IPV6_ADDRFORM for instance)
145 * @sk_err: last error
146 * @sk_err_soft: errors that don't cause failure but are the cause of a persistent failure not just 'timed out'
147 * @sk_ack_backlog: current listen backlog
148 * @sk_max_ack_backlog: listen backlog set in listen()
149 * @sk_priority: %SO_PRIORITY setting
150 * @sk_type: socket type (%SOCK_STREAM, etc)
151 * @sk_protocol: which protocol this socket belongs in this network family
152 * @sk_peercred: %SO_PEERCRED setting
153 * @sk_rcvlowat: %SO_RCVLOWAT setting
154 * @sk_rcvtimeo: %SO_RCVTIMEO setting
155 * @sk_sndtimeo: %SO_SNDTIMEO setting
156 * @sk_filter: socket filtering instructions
157 * @sk_protinfo: private area, net family specific, when not using slab
158 * @sk_timer: sock cleanup timer
159 * @sk_stamp: time stamp of last packet received
160 * @sk_socket: Identd and reporting IO signals
161 * @sk_user_data: RPC layer private data
162 * @sk_sndmsg_page: cached page for sendmsg
163 * @sk_sndmsg_off: cached offset for sendmsg
164 * @sk_send_head: front of stuff to transmit
165 * @sk_security: used by security modules
166 * @sk_write_pending: a write to stream socket waits to start
167 * @sk_state_change: callback to indicate change in the state of the sock
168 * @sk_data_ready: callback to indicate there is data to be processed
169 * @sk_write_space: callback to indicate there is bf sending space available
170 * @sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
171 * @sk_backlog_rcv: callback to process the backlog
172 * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
176 * Now struct tcp_tw_bucket also uses sock_common, so please just
177 * don't add nothing before this first member (__sk_common) --acme
179 struct sock_common __sk_common
;
180 #define sk_family __sk_common.skc_family
181 #define sk_state __sk_common.skc_state
182 #define sk_reuse __sk_common.skc_reuse
183 #define sk_bound_dev_if __sk_common.skc_bound_dev_if
184 #define sk_node __sk_common.skc_node
185 #define sk_bind_node __sk_common.skc_bind_node
186 #define sk_refcnt __sk_common.skc_refcnt
187 unsigned char sk_shutdown
: 2,
190 unsigned char sk_protocol
;
191 unsigned short sk_type
;
193 socket_lock_t sk_lock
;
194 wait_queue_head_t
*sk_sleep
;
195 struct dst_entry
*sk_dst_cache
;
196 struct xfrm_policy
*sk_policy
[2];
197 rwlock_t sk_dst_lock
;
198 atomic_t sk_rmem_alloc
;
199 atomic_t sk_wmem_alloc
;
200 atomic_t sk_omem_alloc
;
201 struct sk_buff_head sk_receive_queue
;
202 struct sk_buff_head sk_write_queue
;
204 int sk_forward_alloc
;
205 unsigned int sk_allocation
;
209 unsigned long sk_flags
;
210 unsigned long sk_lingertime
;
212 * The backlog queue is special, it is always used with
213 * the per-socket spinlock held and requires low latency
214 * access. Therefore we special case it's implementation.
217 struct sk_buff
*head
;
218 struct sk_buff
*tail
;
220 struct sk_buff_head sk_error_queue
;
221 struct proto
*sk_prot
;
222 struct proto
*sk_prot_creator
;
223 rwlock_t sk_callback_lock
;
226 unsigned short sk_ack_backlog
;
227 unsigned short sk_max_ack_backlog
;
229 struct ucred sk_peercred
;
233 struct sk_filter
*sk_filter
;
235 struct timer_list sk_timer
;
236 struct timeval sk_stamp
;
237 struct socket
*sk_socket
;
239 struct page
*sk_sndmsg_page
;
240 struct sk_buff
*sk_send_head
;
242 int sk_write_pending
;
244 void (*sk_state_change
)(struct sock
*sk
);
245 void (*sk_data_ready
)(struct sock
*sk
, int bytes
);
246 void (*sk_write_space
)(struct sock
*sk
);
247 void (*sk_error_report
)(struct sock
*sk
);
248 int (*sk_backlog_rcv
)(struct sock
*sk
,
249 struct sk_buff
*skb
);
250 void (*sk_destruct
)(struct sock
*sk
);
254 * Hashed lists helper routines
256 static inline struct sock
*__sk_head(struct hlist_head
*head
)
258 return hlist_entry(head
->first
, struct sock
, sk_node
);
261 static inline struct sock
*sk_head(struct hlist_head
*head
)
263 return hlist_empty(head
) ? NULL
: __sk_head(head
);
266 static inline struct sock
*sk_next(struct sock
*sk
)
268 return sk
->sk_node
.next
?
269 hlist_entry(sk
->sk_node
.next
, struct sock
, sk_node
) : NULL
;
272 static inline int sk_unhashed(struct sock
*sk
)
274 return hlist_unhashed(&sk
->sk_node
);
277 static inline int sk_hashed(struct sock
*sk
)
279 return sk
->sk_node
.pprev
!= NULL
;
282 static __inline__
void sk_node_init(struct hlist_node
*node
)
287 static __inline__
void __sk_del_node(struct sock
*sk
)
289 __hlist_del(&sk
->sk_node
);
292 static __inline__
int __sk_del_node_init(struct sock
*sk
)
296 sk_node_init(&sk
->sk_node
);
302 /* Grab socket reference count. This operation is valid only
303 when sk is ALREADY grabbed f.e. it is found in hash table
304 or a list and the lookup is made under lock preventing hash table
308 static inline void sock_hold(struct sock
*sk
)
310 atomic_inc(&sk
->sk_refcnt
);
313 /* Ungrab socket in the context, which assumes that socket refcnt
314 cannot hit zero, f.e. it is true in context of any socketcall.
316 static inline void __sock_put(struct sock
*sk
)
318 atomic_dec(&sk
->sk_refcnt
);
321 static __inline__
int sk_del_node_init(struct sock
*sk
)
323 int rc
= __sk_del_node_init(sk
);
326 /* paranoid for a while -acme */
327 WARN_ON(atomic_read(&sk
->sk_refcnt
) == 1);
333 static __inline__
void __sk_add_node(struct sock
*sk
, struct hlist_head
*list
)
335 hlist_add_head(&sk
->sk_node
, list
);
338 static __inline__
void sk_add_node(struct sock
*sk
, struct hlist_head
*list
)
341 __sk_add_node(sk
, list
);
344 static __inline__
void __sk_del_bind_node(struct sock
*sk
)
346 __hlist_del(&sk
->sk_bind_node
);
349 static __inline__
void sk_add_bind_node(struct sock
*sk
,
350 struct hlist_head
*list
)
352 hlist_add_head(&sk
->sk_bind_node
, list
);
355 #define sk_for_each(__sk, node, list) \
356 hlist_for_each_entry(__sk, node, list, sk_node)
357 #define sk_for_each_from(__sk, node) \
358 if (__sk && ({ node = &(__sk)->sk_node; 1; })) \
359 hlist_for_each_entry_from(__sk, node, sk_node)
360 #define sk_for_each_continue(__sk, node) \
361 if (__sk && ({ node = &(__sk)->sk_node; 1; })) \
362 hlist_for_each_entry_continue(__sk, node, sk_node)
363 #define sk_for_each_safe(__sk, node, tmp, list) \
364 hlist_for_each_entry_safe(__sk, node, tmp, list, sk_node)
365 #define sk_for_each_bound(__sk, node, list) \
366 hlist_for_each_entry(__sk, node, list, sk_bind_node)
379 SOCK_USE_WRITE_QUEUE
, /* whether to call sk->sk_write_space in sock_wfree */
380 SOCK_DBG
, /* %SO_DEBUG setting */
381 SOCK_RCVTSTAMP
, /* %SO_TIMESTAMP setting */
382 SOCK_NO_LARGESEND
, /* whether to sent large segments or not */
383 SOCK_LOCALROUTE
, /* route locally only, %SO_DONTROUTE setting */
384 SOCK_QUEUE_SHRUNK
, /* write queue has been shrunk recently */
387 static inline void sock_set_flag(struct sock
*sk
, enum sock_flags flag
)
389 __set_bit(flag
, &sk
->sk_flags
);
392 static inline void sock_reset_flag(struct sock
*sk
, enum sock_flags flag
)
394 __clear_bit(flag
, &sk
->sk_flags
);
397 static inline int sock_flag(struct sock
*sk
, enum sock_flags flag
)
399 return test_bit(flag
, &sk
->sk_flags
);
402 static inline void sk_acceptq_removed(struct sock
*sk
)
404 sk
->sk_ack_backlog
--;
407 static inline void sk_acceptq_added(struct sock
*sk
)
409 sk
->sk_ack_backlog
++;
412 static inline int sk_acceptq_is_full(struct sock
*sk
)
414 return sk
->sk_ack_backlog
> sk
->sk_max_ack_backlog
;
418 * Compute minimal free write space needed to queue new packets.
420 static inline int sk_stream_min_wspace(struct sock
*sk
)
422 return sk
->sk_wmem_queued
/ 2;
425 static inline int sk_stream_wspace(struct sock
*sk
)
427 return sk
->sk_sndbuf
- sk
->sk_wmem_queued
;
430 extern void sk_stream_write_space(struct sock
*sk
);
432 static inline int sk_stream_memory_free(struct sock
*sk
)
434 return sk
->sk_wmem_queued
< sk
->sk_sndbuf
;
437 extern void sk_stream_rfree(struct sk_buff
*skb
);
439 static inline void sk_stream_set_owner_r(struct sk_buff
*skb
, struct sock
*sk
)
442 skb
->destructor
= sk_stream_rfree
;
443 atomic_add(skb
->truesize
, &sk
->sk_rmem_alloc
);
444 sk
->sk_forward_alloc
-= skb
->truesize
;
447 static inline void sk_stream_free_skb(struct sock
*sk
, struct sk_buff
*skb
)
449 sock_set_flag(sk
, SOCK_QUEUE_SHRUNK
);
450 sk
->sk_wmem_queued
-= skb
->truesize
;
451 sk
->sk_forward_alloc
+= skb
->truesize
;
455 /* The per-socket spinlock must be held here. */
456 #define sk_add_backlog(__sk, __skb) \
457 do { if (!(__sk)->sk_backlog.tail) { \
458 (__sk)->sk_backlog.head = \
459 (__sk)->sk_backlog.tail = (__skb); \
461 ((__sk)->sk_backlog.tail)->next = (__skb); \
462 (__sk)->sk_backlog.tail = (__skb); \
464 (__skb)->next = NULL; \
467 #define sk_wait_event(__sk, __timeo, __condition) \
469 release_sock(__sk); \
472 *(__timeo) = schedule_timeout(*(__timeo)); \
479 extern int sk_stream_wait_connect(struct sock
*sk
, long *timeo_p
);
480 extern int sk_stream_wait_memory(struct sock
*sk
, long *timeo_p
);
481 extern void sk_stream_wait_close(struct sock
*sk
, long timeo_p
);
482 extern int sk_stream_error(struct sock
*sk
, int flags
, int err
);
483 extern void sk_stream_kill_queues(struct sock
*sk
);
485 extern int sk_wait_data(struct sock
*sk
, long *timeo
);
487 struct request_sock_ops
;
489 /* Networking protocol blocks we attach to sockets.
490 * socket layer -> transport layer interface
491 * transport -> network interface is defined by struct inet_proto
494 void (*close
)(struct sock
*sk
,
496 int (*connect
)(struct sock
*sk
,
497 struct sockaddr
*uaddr
,
499 int (*disconnect
)(struct sock
*sk
, int flags
);
501 struct sock
* (*accept
) (struct sock
*sk
, int flags
, int *err
);
503 int (*ioctl
)(struct sock
*sk
, int cmd
,
505 int (*init
)(struct sock
*sk
);
506 int (*destroy
)(struct sock
*sk
);
507 void (*shutdown
)(struct sock
*sk
, int how
);
508 int (*setsockopt
)(struct sock
*sk
, int level
,
509 int optname
, char __user
*optval
,
511 int (*getsockopt
)(struct sock
*sk
, int level
,
512 int optname
, char __user
*optval
,
514 int (*sendmsg
)(struct kiocb
*iocb
, struct sock
*sk
,
515 struct msghdr
*msg
, size_t len
);
516 int (*recvmsg
)(struct kiocb
*iocb
, struct sock
*sk
,
518 size_t len
, int noblock
, int flags
,
520 int (*sendpage
)(struct sock
*sk
, struct page
*page
,
521 int offset
, size_t size
, int flags
);
522 int (*bind
)(struct sock
*sk
,
523 struct sockaddr
*uaddr
, int addr_len
);
525 int (*backlog_rcv
) (struct sock
*sk
,
526 struct sk_buff
*skb
);
528 /* Keeping track of sk's, looking them up, and port selection methods. */
529 void (*hash
)(struct sock
*sk
);
530 void (*unhash
)(struct sock
*sk
);
531 int (*get_port
)(struct sock
*sk
, unsigned short snum
);
533 /* Memory pressure */
534 void (*enter_memory_pressure
)(void);
535 atomic_t
*memory_allocated
; /* Current allocated memory. */
536 atomic_t
*sockets_allocated
; /* Current number of sockets. */
538 * Pressure flag: try to collapse.
539 * Technical note: it is used by multiple contexts non atomically.
540 * All the sk_stream_mem_schedule() is of this nature: accounting
541 * is strict, actions are advisory and have some latency.
543 int *memory_pressure
;
550 unsigned int obj_size
;
552 struct request_sock_ops
*rsk_prot
;
554 struct module
*owner
;
558 struct list_head node
;
562 u8 __pad
[SMP_CACHE_BYTES
- sizeof(int)];
566 extern int proto_register(struct proto
*prot
, int alloc_slab
);
567 extern void proto_unregister(struct proto
*prot
);
569 /* Called with local bh disabled */
570 static __inline__
void sock_prot_inc_use(struct proto
*prot
)
572 prot
->stats
[smp_processor_id()].inuse
++;
575 static __inline__
void sock_prot_dec_use(struct proto
*prot
)
577 prot
->stats
[smp_processor_id()].inuse
--;
580 /* About 10 seconds */
581 #define SOCK_DESTROY_TIME (10*HZ)
583 /* Sockets 0-1023 can't be bound to unless you are superuser */
584 #define PROT_SOCK 1024
586 #define SHUTDOWN_MASK 3
587 #define RCV_SHUTDOWN 1
588 #define SEND_SHUTDOWN 2
590 #define SOCK_SNDBUF_LOCK 1
591 #define SOCK_RCVBUF_LOCK 2
592 #define SOCK_BINDADDR_LOCK 4
593 #define SOCK_BINDPORT_LOCK 8
595 /* sock_iocb: used to kick off async processing of socket ios */
597 struct list_head list
;
603 struct scm_cookie
*scm
;
604 struct msghdr
*msg
, async_msg
;
605 struct iovec async_iov
;
609 static inline struct sock_iocb
*kiocb_to_siocb(struct kiocb
*iocb
)
611 return (struct sock_iocb
*)iocb
->private;
614 static inline struct kiocb
*siocb_to_kiocb(struct sock_iocb
*si
)
619 struct socket_alloc
{
620 struct socket socket
;
621 struct inode vfs_inode
;
624 static inline struct socket
*SOCKET_I(struct inode
*inode
)
626 return &container_of(inode
, struct socket_alloc
, vfs_inode
)->socket
;
629 static inline struct inode
*SOCK_INODE(struct socket
*socket
)
631 return &container_of(socket
, struct socket_alloc
, socket
)->vfs_inode
;
634 extern void __sk_stream_mem_reclaim(struct sock
*sk
);
635 extern int sk_stream_mem_schedule(struct sock
*sk
, int size
, int kind
);
637 #define SK_STREAM_MEM_QUANTUM ((int)PAGE_SIZE)
639 static inline int sk_stream_pages(int amt
)
641 return (amt
+ SK_STREAM_MEM_QUANTUM
- 1) / SK_STREAM_MEM_QUANTUM
;
644 static inline void sk_stream_mem_reclaim(struct sock
*sk
)
646 if (sk
->sk_forward_alloc
>= SK_STREAM_MEM_QUANTUM
)
647 __sk_stream_mem_reclaim(sk
);
650 static inline void sk_stream_writequeue_purge(struct sock
*sk
)
654 while ((skb
= __skb_dequeue(&sk
->sk_write_queue
)) != NULL
)
655 sk_stream_free_skb(sk
, skb
);
656 sk_stream_mem_reclaim(sk
);
659 static inline int sk_stream_rmem_schedule(struct sock
*sk
, struct sk_buff
*skb
)
661 return (int)skb
->truesize
<= sk
->sk_forward_alloc
||
662 sk_stream_mem_schedule(sk
, skb
->truesize
, 1);
665 /* Used by processes to "lock" a socket state, so that
666 * interrupts and bottom half handlers won't change it
667 * from under us. It essentially blocks any incoming
668 * packets, so that we won't get any new data or any
669 * packets that change the state of the socket.
671 * While locked, BH processing will add new packets to
672 * the backlog queue. This queue is processed by the
673 * owner of the socket lock right before it is released.
675 * Since ~2.3.5 it is also exclusive sleep lock serializing
676 * accesses from user process context.
678 #define sock_owned_by_user(sk) ((sk)->sk_lock.owner)
680 extern void FASTCALL(lock_sock(struct sock
*sk
));
681 extern void FASTCALL(release_sock(struct sock
*sk
));
683 /* BH context may only use the following locking interface. */
684 #define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock))
685 #define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock))
687 extern struct sock
*sk_alloc(int family
,
688 unsigned int __nocast priority
,
689 struct proto
*prot
, int zero_it
);
690 extern void sk_free(struct sock
*sk
);
692 extern struct sk_buff
*sock_wmalloc(struct sock
*sk
,
693 unsigned long size
, int force
,
694 unsigned int __nocast priority
);
695 extern struct sk_buff
*sock_rmalloc(struct sock
*sk
,
696 unsigned long size
, int force
,
697 unsigned int __nocast priority
);
698 extern void sock_wfree(struct sk_buff
*skb
);
699 extern void sock_rfree(struct sk_buff
*skb
);
701 extern int sock_setsockopt(struct socket
*sock
, int level
,
702 int op
, char __user
*optval
,
705 extern int sock_getsockopt(struct socket
*sock
, int level
,
706 int op
, char __user
*optval
,
708 extern struct sk_buff
*sock_alloc_send_skb(struct sock
*sk
,
712 extern void *sock_kmalloc(struct sock
*sk
, int size
,
713 unsigned int __nocast priority
);
714 extern void sock_kfree_s(struct sock
*sk
, void *mem
, int size
);
715 extern void sk_send_sigurg(struct sock
*sk
);
718 * Functions to fill in entries in struct proto_ops when a protocol
719 * does not implement a particular function.
721 extern int sock_no_bind(struct socket
*,
722 struct sockaddr
*, int);
723 extern int sock_no_connect(struct socket
*,
724 struct sockaddr
*, int, int);
725 extern int sock_no_socketpair(struct socket
*,
727 extern int sock_no_accept(struct socket
*,
728 struct socket
*, int);
729 extern int sock_no_getname(struct socket
*,
730 struct sockaddr
*, int *, int);
731 extern unsigned int sock_no_poll(struct file
*, struct socket
*,
732 struct poll_table_struct
*);
733 extern int sock_no_ioctl(struct socket
*, unsigned int,
735 extern int sock_no_listen(struct socket
*, int);
736 extern int sock_no_shutdown(struct socket
*, int);
737 extern int sock_no_getsockopt(struct socket
*, int , int,
738 char __user
*, int __user
*);
739 extern int sock_no_setsockopt(struct socket
*, int, int,
741 extern int sock_no_sendmsg(struct kiocb
*, struct socket
*,
742 struct msghdr
*, size_t);
743 extern int sock_no_recvmsg(struct kiocb
*, struct socket
*,
744 struct msghdr
*, size_t, int);
745 extern int sock_no_mmap(struct file
*file
,
747 struct vm_area_struct
*vma
);
748 extern ssize_t
sock_no_sendpage(struct socket
*sock
,
750 int offset
, size_t size
,
754 * Functions to fill in entries in struct proto_ops when a protocol
755 * uses the inet style.
757 extern int sock_common_getsockopt(struct socket
*sock
, int level
, int optname
,
758 char __user
*optval
, int __user
*optlen
);
759 extern int sock_common_recvmsg(struct kiocb
*iocb
, struct socket
*sock
,
760 struct msghdr
*msg
, size_t size
, int flags
);
761 extern int sock_common_setsockopt(struct socket
*sock
, int level
, int optname
,
762 char __user
*optval
, int optlen
);
764 extern void sk_common_release(struct sock
*sk
);
767 * Default socket callbacks and setup code
770 /* Initialise core socket variables */
771 extern void sock_init_data(struct socket
*sock
, struct sock
*sk
);
774 * sk_filter - run a packet through a socket filter
775 * @sk: sock associated with &sk_buff
776 * @skb: buffer to filter
777 * @needlock: set to 1 if the sock is not locked by caller.
779 * Run the filter code and then cut skb->data to correct size returned by
780 * sk_run_filter. If pkt_len is 0 we toss packet. If skb->len is smaller
781 * than pkt_len we keep whole skb->data. This is the socket level
782 * wrapper to sk_run_filter. It returns 0 if the packet should
783 * be accepted or -EPERM if the packet should be tossed.
787 static inline int sk_filter(struct sock
*sk
, struct sk_buff
*skb
, int needlock
)
791 err
= security_sock_rcv_skb(sk
, skb
);
796 struct sk_filter
*filter
;
801 filter
= sk
->sk_filter
;
803 int pkt_len
= sk_run_filter(skb
, filter
->insns
,
808 skb_trim(skb
, pkt_len
);
818 * sk_filter_release: Release a socket filter
820 * @fp: filter to remove
822 * Remove a filter from a socket and release its resources.
825 static inline void sk_filter_release(struct sock
*sk
, struct sk_filter
*fp
)
827 unsigned int size
= sk_filter_len(fp
);
829 atomic_sub(size
, &sk
->sk_omem_alloc
);
831 if (atomic_dec_and_test(&fp
->refcnt
))
835 static inline void sk_filter_charge(struct sock
*sk
, struct sk_filter
*fp
)
837 atomic_inc(&fp
->refcnt
);
838 atomic_add(sk_filter_len(fp
), &sk
->sk_omem_alloc
);
842 * Socket reference counting postulates.
844 * * Each user of socket SHOULD hold a reference count.
845 * * Each access point to socket (an hash table bucket, reference from a list,
846 * running timer, skb in flight MUST hold a reference count.
847 * * When reference count hits 0, it means it will never increase back.
848 * * When reference count hits 0, it means that no references from
849 * outside exist to this socket and current process on current CPU
850 * is last user and may/should destroy this socket.
851 * * sk_free is called from any context: process, BH, IRQ. When
852 * it is called, socket has no references from outside -> sk_free
853 * may release descendant resources allocated by the socket, but
854 * to the time when it is called, socket is NOT referenced by any
855 * hash tables, lists etc.
856 * * Packets, delivered from outside (from network or from another process)
857 * and enqueued on receive/error queues SHOULD NOT grab reference count,
858 * when they sit in queue. Otherwise, packets will leak to hole, when
859 * socket is looked up by one cpu and unhasing is made by another CPU.
860 * It is true for udp/raw, netlink (leak to receive and error queues), tcp
861 * (leak to backlog). Packet socket does all the processing inside
862 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
863 * use separate SMP lock, so that they are prone too.
866 /* Ungrab socket and destroy it, if it was the last reference. */
867 static inline void sock_put(struct sock
*sk
)
869 if (atomic_dec_and_test(&sk
->sk_refcnt
))
873 /* Detach socket from process context.
874 * Announce socket dead, detach it from wait queue and inode.
875 * Note that parent inode held reference count on this struct sock,
876 * we do not release it in this function, because protocol
877 * probably wants some additional cleanups or even continuing
878 * to work with this socket (TCP).
880 static inline void sock_orphan(struct sock
*sk
)
882 write_lock_bh(&sk
->sk_callback_lock
);
883 sock_set_flag(sk
, SOCK_DEAD
);
884 sk
->sk_socket
= NULL
;
886 write_unlock_bh(&sk
->sk_callback_lock
);
889 static inline void sock_graft(struct sock
*sk
, struct socket
*parent
)
891 write_lock_bh(&sk
->sk_callback_lock
);
892 sk
->sk_sleep
= &parent
->wait
;
894 sk
->sk_socket
= parent
;
895 write_unlock_bh(&sk
->sk_callback_lock
);
898 extern int sock_i_uid(struct sock
*sk
);
899 extern unsigned long sock_i_ino(struct sock
*sk
);
901 static inline struct dst_entry
*
902 __sk_dst_get(struct sock
*sk
)
904 return sk
->sk_dst_cache
;
907 static inline struct dst_entry
*
908 sk_dst_get(struct sock
*sk
)
910 struct dst_entry
*dst
;
912 read_lock(&sk
->sk_dst_lock
);
913 dst
= sk
->sk_dst_cache
;
916 read_unlock(&sk
->sk_dst_lock
);
921 __sk_dst_set(struct sock
*sk
, struct dst_entry
*dst
)
923 struct dst_entry
*old_dst
;
925 old_dst
= sk
->sk_dst_cache
;
926 sk
->sk_dst_cache
= dst
;
927 dst_release(old_dst
);
931 sk_dst_set(struct sock
*sk
, struct dst_entry
*dst
)
933 write_lock(&sk
->sk_dst_lock
);
934 __sk_dst_set(sk
, dst
);
935 write_unlock(&sk
->sk_dst_lock
);
939 __sk_dst_reset(struct sock
*sk
)
941 struct dst_entry
*old_dst
;
943 old_dst
= sk
->sk_dst_cache
;
944 sk
->sk_dst_cache
= NULL
;
945 dst_release(old_dst
);
949 sk_dst_reset(struct sock
*sk
)
951 write_lock(&sk
->sk_dst_lock
);
953 write_unlock(&sk
->sk_dst_lock
);
956 static inline struct dst_entry
*
957 __sk_dst_check(struct sock
*sk
, u32 cookie
)
959 struct dst_entry
*dst
= sk
->sk_dst_cache
;
961 if (dst
&& dst
->obsolete
&& dst
->ops
->check(dst
, cookie
) == NULL
) {
962 sk
->sk_dst_cache
= NULL
;
970 static inline struct dst_entry
*
971 sk_dst_check(struct sock
*sk
, u32 cookie
)
973 struct dst_entry
*dst
= sk_dst_get(sk
);
975 if (dst
&& dst
->obsolete
&& dst
->ops
->check(dst
, cookie
) == NULL
) {
984 static inline void sk_charge_skb(struct sock
*sk
, struct sk_buff
*skb
)
986 sk
->sk_wmem_queued
+= skb
->truesize
;
987 sk
->sk_forward_alloc
-= skb
->truesize
;
990 static inline int skb_copy_to_page(struct sock
*sk
, char __user
*from
,
991 struct sk_buff
*skb
, struct page
*page
,
994 if (skb
->ip_summed
== CHECKSUM_NONE
) {
996 unsigned int csum
= csum_and_copy_from_user(from
,
997 page_address(page
) + off
,
1001 skb
->csum
= csum_block_add(skb
->csum
, csum
, skb
->len
);
1002 } else if (copy_from_user(page_address(page
) + off
, from
, copy
))
1006 skb
->data_len
+= copy
;
1007 skb
->truesize
+= copy
;
1008 sk
->sk_wmem_queued
+= copy
;
1009 sk
->sk_forward_alloc
-= copy
;
1014 * Queue a received datagram if it will fit. Stream and sequenced
1015 * protocols can't normally use this as they need to fit buffers in
1016 * and play with them.
1018 * Inlined as it's very short and called for pretty much every
1019 * packet ever received.
1022 static inline void skb_set_owner_w(struct sk_buff
*skb
, struct sock
*sk
)
1026 skb
->destructor
= sock_wfree
;
1027 atomic_add(skb
->truesize
, &sk
->sk_wmem_alloc
);
1030 static inline void skb_set_owner_r(struct sk_buff
*skb
, struct sock
*sk
)
1033 skb
->destructor
= sock_rfree
;
1034 atomic_add(skb
->truesize
, &sk
->sk_rmem_alloc
);
1037 extern void sk_reset_timer(struct sock
*sk
, struct timer_list
* timer
,
1038 unsigned long expires
);
1040 extern void sk_stop_timer(struct sock
*sk
, struct timer_list
* timer
);
1042 static inline int sock_queue_rcv_skb(struct sock
*sk
, struct sk_buff
*skb
)
1047 /* Cast skb->rcvbuf to unsigned... It's pointless, but reduces
1048 number of warnings when compiling with -W --ANK
1050 if (atomic_read(&sk
->sk_rmem_alloc
) + skb
->truesize
>=
1051 (unsigned)sk
->sk_rcvbuf
) {
1056 /* It would be deadlock, if sock_queue_rcv_skb is used
1057 with socket lock! We assume that users of this
1058 function are lock free.
1060 err
= sk_filter(sk
, skb
, 1);
1065 skb_set_owner_r(skb
, sk
);
1067 /* Cache the SKB length before we tack it onto the receive
1068 * queue. Once it is added it no longer belongs to us and
1069 * may be freed by other threads of control pulling packets
1074 skb_queue_tail(&sk
->sk_receive_queue
, skb
);
1076 if (!sock_flag(sk
, SOCK_DEAD
))
1077 sk
->sk_data_ready(sk
, skb_len
);
1082 static inline int sock_queue_err_skb(struct sock
*sk
, struct sk_buff
*skb
)
1084 /* Cast skb->rcvbuf to unsigned... It's pointless, but reduces
1085 number of warnings when compiling with -W --ANK
1087 if (atomic_read(&sk
->sk_rmem_alloc
) + skb
->truesize
>=
1088 (unsigned)sk
->sk_rcvbuf
)
1090 skb_set_owner_r(skb
, sk
);
1091 skb_queue_tail(&sk
->sk_error_queue
, skb
);
1092 if (!sock_flag(sk
, SOCK_DEAD
))
1093 sk
->sk_data_ready(sk
, skb
->len
);
1098 * Recover an error report and clear atomically
1101 static inline int sock_error(struct sock
*sk
)
1103 int err
= xchg(&sk
->sk_err
, 0);
1107 static inline unsigned long sock_wspace(struct sock
*sk
)
1111 if (!(sk
->sk_shutdown
& SEND_SHUTDOWN
)) {
1112 amt
= sk
->sk_sndbuf
- atomic_read(&sk
->sk_wmem_alloc
);
1119 static inline void sk_wake_async(struct sock
*sk
, int how
, int band
)
1121 if (sk
->sk_socket
&& sk
->sk_socket
->fasync_list
)
1122 sock_wake_async(sk
->sk_socket
, how
, band
);
1125 #define SOCK_MIN_SNDBUF 2048
1126 #define SOCK_MIN_RCVBUF 256
1128 static inline void sk_stream_moderate_sndbuf(struct sock
*sk
)
1130 if (!(sk
->sk_userlocks
& SOCK_SNDBUF_LOCK
)) {
1131 sk
->sk_sndbuf
= min(sk
->sk_sndbuf
, sk
->sk_wmem_queued
/ 2);
1132 sk
->sk_sndbuf
= max(sk
->sk_sndbuf
, SOCK_MIN_SNDBUF
);
1136 static inline struct sk_buff
*sk_stream_alloc_pskb(struct sock
*sk
,
1138 unsigned int __nocast gfp
)
1140 struct sk_buff
*skb
;
1143 hdr_len
= SKB_DATA_ALIGN(sk
->sk_prot
->max_header
);
1144 skb
= alloc_skb(size
+ hdr_len
, gfp
);
1146 skb
->truesize
+= mem
;
1147 if (sk
->sk_forward_alloc
>= (int)skb
->truesize
||
1148 sk_stream_mem_schedule(sk
, skb
->truesize
, 0)) {
1149 skb_reserve(skb
, hdr_len
);
1154 sk
->sk_prot
->enter_memory_pressure();
1155 sk_stream_moderate_sndbuf(sk
);
1160 static inline struct sk_buff
*sk_stream_alloc_skb(struct sock
*sk
,
1162 unsigned int __nocast gfp
)
1164 return sk_stream_alloc_pskb(sk
, size
, 0, gfp
);
1167 static inline struct page
*sk_stream_alloc_page(struct sock
*sk
)
1169 struct page
*page
= NULL
;
1171 if (sk
->sk_forward_alloc
>= (int)PAGE_SIZE
||
1172 sk_stream_mem_schedule(sk
, PAGE_SIZE
, 0))
1173 page
= alloc_pages(sk
->sk_allocation
, 0);
1175 sk
->sk_prot
->enter_memory_pressure();
1176 sk_stream_moderate_sndbuf(sk
);
1181 #define sk_stream_for_retrans_queue(skb, sk) \
1182 for (skb = (sk)->sk_write_queue.next; \
1183 (skb != (sk)->sk_send_head) && \
1184 (skb != (struct sk_buff *)&(sk)->sk_write_queue); \
1188 * Default write policy as shown to user space via poll/select/SIGIO
1190 static inline int sock_writeable(const struct sock
*sk
)
1192 return atomic_read(&sk
->sk_wmem_alloc
) < (sk
->sk_sndbuf
/ 2);
1195 static inline unsigned int __nocast
gfp_any(void)
1197 return in_softirq() ? GFP_ATOMIC
: GFP_KERNEL
;
1200 static inline long sock_rcvtimeo(const struct sock
*sk
, int noblock
)
1202 return noblock
? 0 : sk
->sk_rcvtimeo
;
1205 static inline long sock_sndtimeo(const struct sock
*sk
, int noblock
)
1207 return noblock
? 0 : sk
->sk_sndtimeo
;
1210 static inline int sock_rcvlowat(const struct sock
*sk
, int waitall
, int len
)
1212 return (waitall
? len
: min_t(int, sk
->sk_rcvlowat
, len
)) ? : 1;
1215 /* Alas, with timeout socket operations are not restartable.
1216 * Compare this to poll().
1218 static inline int sock_intr_errno(long timeo
)
1220 return timeo
== MAX_SCHEDULE_TIMEOUT
? -ERESTARTSYS
: -EINTR
;
1223 static __inline__
void
1224 sock_recv_timestamp(struct msghdr
*msg
, struct sock
*sk
, struct sk_buff
*skb
)
1226 struct timeval
*stamp
= &skb
->stamp
;
1227 if (sock_flag(sk
, SOCK_RCVTSTAMP
)) {
1228 /* Race occurred between timestamp enabling and packet
1229 receiving. Fill in the current time for now. */
1230 if (stamp
->tv_sec
== 0)
1231 do_gettimeofday(stamp
);
1232 put_cmsg(msg
, SOL_SOCKET
, SO_TIMESTAMP
, sizeof(struct timeval
),
1235 sk
->sk_stamp
= *stamp
;
1239 * sk_eat_skb - Release a skb if it is no longer needed
1240 * @sk: socket to eat this skb from
1241 * @skb: socket buffer to eat
1243 * This routine must be called with interrupts disabled or with the socket
1244 * locked so that the sk_buff queue operation is ok.
1246 static inline void sk_eat_skb(struct sock
*sk
, struct sk_buff
*skb
)
1248 __skb_unlink(skb
, &sk
->sk_receive_queue
);
1252 extern void sock_enable_timestamp(struct sock
*sk
);
1253 extern int sock_get_timestamp(struct sock
*, struct timeval __user
*);
1256 * Enable debug/info messages
1260 #define NETDEBUG(x) do { } while (0)
1261 #define LIMIT_NETDEBUG(x) do {} while(0)
1263 #define NETDEBUG(x) do { x; } while (0)
1264 #define LIMIT_NETDEBUG(x) do { if (net_ratelimit()) { x; } } while(0)
1268 * Macros for sleeping on a socket. Use them like this:
1270 * SOCK_SLEEP_PRE(sk)
1273 * SOCK_SLEEP_POST(sk)
1275 * N.B. These are now obsolete and were, afaik, only ever used in DECnet
1276 * and when the last use of them in DECnet has gone, I'm intending to
1280 #define SOCK_SLEEP_PRE(sk) { struct task_struct *tsk = current; \
1281 DECLARE_WAITQUEUE(wait, tsk); \
1282 tsk->state = TASK_INTERRUPTIBLE; \
1283 add_wait_queue((sk)->sk_sleep, &wait); \
1286 #define SOCK_SLEEP_POST(sk) tsk->state = TASK_RUNNING; \
1287 remove_wait_queue((sk)->sk_sleep, &wait); \
1291 static inline void sock_valbool_flag(struct sock
*sk
, int bit
, int valbool
)
1294 sock_set_flag(sk
, bit
);
1296 sock_reset_flag(sk
, bit
);
1299 extern __u32 sysctl_wmem_max
;
1300 extern __u32 sysctl_rmem_max
;
1303 int siocdevprivate_ioctl(unsigned int fd
, unsigned int cmd
, unsigned long arg
);
1305 static inline int siocdevprivate_ioctl(unsigned int fd
, unsigned int cmd
, unsigned long arg
)
1311 #endif /* _SOCK_H */