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/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 */
53 #include <linux/security.h>
54 #include <linux/slab.h>
55 #include <linux/uaccess.h>
56 #include <linux/memcontrol.h>
57 #include <linux/res_counter.h>
58 #include <linux/static_key.h>
59 #include <linux/aio.h>
60 #include <linux/sched.h>
62 #include <linux/filter.h>
63 #include <linux/rculist_nulls.h>
64 #include <linux/poll.h>
66 #include <linux/atomic.h>
68 #include <net/checksum.h>
73 int mem_cgroup_sockets_init(struct cgroup
*cgrp
, struct cgroup_subsys
*ss
);
74 void mem_cgroup_sockets_destroy(struct cgroup
*cgrp
);
77 int mem_cgroup_sockets_init(struct cgroup
*cgrp
, struct cgroup_subsys
*ss
)
82 void mem_cgroup_sockets_destroy(struct cgroup
*cgrp
)
87 * This structure really needs to be cleaned up.
88 * Most of it is for TCP, and not used by any of
89 * the other protocols.
92 /* Define this to get the SOCK_DBG debugging facility. */
93 #define SOCK_DEBUGGING
95 #define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \
96 printk(KERN_DEBUG msg); } while (0)
98 /* Validate arguments and do nothing */
99 static inline __printf(2, 3)
100 void SOCK_DEBUG(struct sock
*sk
, const char *msg
, ...)
105 /* This is the per-socket lock. The spinlock provides a synchronization
106 * between user contexts and software interrupt processing, whereas the
107 * mini-semaphore synchronizes multiple users amongst themselves.
112 wait_queue_head_t wq
;
114 * We express the mutex-alike socket_lock semantics
115 * to the lock validator by explicitly managing
116 * the slock as a lock variant (in addition to
119 #ifdef CONFIG_DEBUG_LOCK_ALLOC
120 struct lockdep_map dep_map
;
129 * struct sock_common - minimal network layer representation of sockets
130 * @skc_daddr: Foreign IPv4 addr
131 * @skc_rcv_saddr: Bound local IPv4 addr
132 * @skc_hash: hash value used with various protocol lookup tables
133 * @skc_u16hashes: two u16 hash values used by UDP lookup tables
134 * @skc_family: network address family
135 * @skc_state: Connection state
136 * @skc_reuse: %SO_REUSEADDR setting
137 * @skc_bound_dev_if: bound device index if != 0
138 * @skc_bind_node: bind hash linkage for various protocol lookup tables
139 * @skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol
140 * @skc_prot: protocol handlers inside a network family
141 * @skc_net: reference to the network namespace of this socket
142 * @skc_node: main hash linkage for various protocol lookup tables
143 * @skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol
144 * @skc_tx_queue_mapping: tx queue number for this connection
145 * @skc_refcnt: reference count
147 * This is the minimal network layer representation of sockets, the header
148 * for struct sock and struct inet_timewait_sock.
151 /* skc_daddr and skc_rcv_saddr must be grouped :
152 * cf INET_MATCH() and INET_TW_MATCH()
155 __be32 skc_rcv_saddr
;
158 unsigned int skc_hash
;
159 __u16 skc_u16hashes
[2];
161 unsigned short skc_family
;
162 volatile unsigned char skc_state
;
163 unsigned char skc_reuse
;
164 int skc_bound_dev_if
;
166 struct hlist_node skc_bind_node
;
167 struct hlist_nulls_node skc_portaddr_node
;
169 struct proto
*skc_prot
;
174 * fields between dontcopy_begin/dontcopy_end
175 * are not copied in sock_copy()
178 int skc_dontcopy_begin
[0];
181 struct hlist_node skc_node
;
182 struct hlist_nulls_node skc_nulls_node
;
184 int skc_tx_queue_mapping
;
187 int skc_dontcopy_end
[0];
193 * struct sock - network layer representation of sockets
194 * @__sk_common: shared layout with inet_timewait_sock
195 * @sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
196 * @sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
197 * @sk_lock: synchronizer
198 * @sk_rcvbuf: size of receive buffer in bytes
199 * @sk_wq: sock wait queue and async head
200 * @sk_dst_cache: destination cache
201 * @sk_dst_lock: destination cache lock
202 * @sk_policy: flow policy
203 * @sk_receive_queue: incoming packets
204 * @sk_wmem_alloc: transmit queue bytes committed
205 * @sk_write_queue: Packet sending queue
206 * @sk_async_wait_queue: DMA copied packets
207 * @sk_omem_alloc: "o" is "option" or "other"
208 * @sk_wmem_queued: persistent queue size
209 * @sk_forward_alloc: space allocated forward
210 * @sk_allocation: allocation mode
211 * @sk_sndbuf: size of send buffer in bytes
212 * @sk_flags: %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE,
213 * %SO_OOBINLINE settings, %SO_TIMESTAMPING settings
214 * @sk_no_check: %SO_NO_CHECK setting, wether or not checkup packets
215 * @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
216 * @sk_route_nocaps: forbidden route capabilities (e.g NETIF_F_GSO_MASK)
217 * @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
218 * @sk_gso_max_size: Maximum GSO segment size to build
219 * @sk_lingertime: %SO_LINGER l_linger setting
220 * @sk_backlog: always used with the per-socket spinlock held
221 * @sk_callback_lock: used with the callbacks in the end of this struct
222 * @sk_error_queue: rarely used
223 * @sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt,
224 * IPV6_ADDRFORM for instance)
225 * @sk_err: last error
226 * @sk_err_soft: errors that don't cause failure but are the cause of a
227 * persistent failure not just 'timed out'
228 * @sk_drops: raw/udp drops counter
229 * @sk_ack_backlog: current listen backlog
230 * @sk_max_ack_backlog: listen backlog set in listen()
231 * @sk_priority: %SO_PRIORITY setting
232 * @sk_cgrp_prioidx: socket group's priority map index
233 * @sk_type: socket type (%SOCK_STREAM, etc)
234 * @sk_protocol: which protocol this socket belongs in this network family
235 * @sk_peer_pid: &struct pid for this socket's peer
236 * @sk_peer_cred: %SO_PEERCRED setting
237 * @sk_rcvlowat: %SO_RCVLOWAT setting
238 * @sk_rcvtimeo: %SO_RCVTIMEO setting
239 * @sk_sndtimeo: %SO_SNDTIMEO setting
240 * @sk_rxhash: flow hash received from netif layer
241 * @sk_filter: socket filtering instructions
242 * @sk_protinfo: private area, net family specific, when not using slab
243 * @sk_timer: sock cleanup timer
244 * @sk_stamp: time stamp of last packet received
245 * @sk_socket: Identd and reporting IO signals
246 * @sk_user_data: RPC layer private data
247 * @sk_sndmsg_page: cached page for sendmsg
248 * @sk_sndmsg_off: cached offset for sendmsg
249 * @sk_peek_off: current peek_offset value
250 * @sk_send_head: front of stuff to transmit
251 * @sk_security: used by security modules
252 * @sk_mark: generic packet mark
253 * @sk_classid: this socket's cgroup classid
254 * @sk_cgrp: this socket's cgroup-specific proto data
255 * @sk_write_pending: a write to stream socket waits to start
256 * @sk_state_change: callback to indicate change in the state of the sock
257 * @sk_data_ready: callback to indicate there is data to be processed
258 * @sk_write_space: callback to indicate there is bf sending space available
259 * @sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
260 * @sk_backlog_rcv: callback to process the backlog
261 * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
265 * Now struct inet_timewait_sock also uses sock_common, so please just
266 * don't add nothing before this first member (__sk_common) --acme
268 struct sock_common __sk_common
;
269 #define sk_node __sk_common.skc_node
270 #define sk_nulls_node __sk_common.skc_nulls_node
271 #define sk_refcnt __sk_common.skc_refcnt
272 #define sk_tx_queue_mapping __sk_common.skc_tx_queue_mapping
274 #define sk_dontcopy_begin __sk_common.skc_dontcopy_begin
275 #define sk_dontcopy_end __sk_common.skc_dontcopy_end
276 #define sk_hash __sk_common.skc_hash
277 #define sk_family __sk_common.skc_family
278 #define sk_state __sk_common.skc_state
279 #define sk_reuse __sk_common.skc_reuse
280 #define sk_bound_dev_if __sk_common.skc_bound_dev_if
281 #define sk_bind_node __sk_common.skc_bind_node
282 #define sk_prot __sk_common.skc_prot
283 #define sk_net __sk_common.skc_net
284 socket_lock_t sk_lock
;
285 struct sk_buff_head sk_receive_queue
;
287 * The backlog queue is special, it is always used with
288 * the per-socket spinlock held and requires low latency
289 * access. Therefore we special case it's implementation.
290 * Note : rmem_alloc is in this structure to fill a hole
291 * on 64bit arches, not because its logically part of
297 struct sk_buff
*head
;
298 struct sk_buff
*tail
;
300 #define sk_rmem_alloc sk_backlog.rmem_alloc
301 int sk_forward_alloc
;
308 struct sk_filter __rcu
*sk_filter
;
309 struct socket_wq __rcu
*sk_wq
;
311 #ifdef CONFIG_NET_DMA
312 struct sk_buff_head sk_async_wait_queue
;
316 struct xfrm_policy
*sk_policy
[2];
318 unsigned long sk_flags
;
319 struct dst_entry
*sk_dst_cache
;
320 spinlock_t sk_dst_lock
;
321 atomic_t sk_wmem_alloc
;
322 atomic_t sk_omem_alloc
;
324 struct sk_buff_head sk_write_queue
;
325 kmemcheck_bitfield_begin(flags
);
326 unsigned int sk_shutdown
: 2,
331 kmemcheck_bitfield_end(flags
);
334 netdev_features_t sk_route_caps
;
335 netdev_features_t sk_route_nocaps
;
337 unsigned int sk_gso_max_size
;
339 unsigned long sk_lingertime
;
340 struct sk_buff_head sk_error_queue
;
341 struct proto
*sk_prot_creator
;
342 rwlock_t sk_callback_lock
;
345 unsigned short sk_ack_backlog
;
346 unsigned short sk_max_ack_backlog
;
348 #ifdef CONFIG_CGROUPS
349 __u32 sk_cgrp_prioidx
;
351 struct pid
*sk_peer_pid
;
352 const struct cred
*sk_peer_cred
;
356 struct timer_list sk_timer
;
358 struct socket
*sk_socket
;
360 struct page
*sk_sndmsg_page
;
361 struct sk_buff
*sk_send_head
;
364 int sk_write_pending
;
365 #ifdef CONFIG_SECURITY
370 struct cg_proto
*sk_cgrp
;
371 void (*sk_state_change
)(struct sock
*sk
);
372 void (*sk_data_ready
)(struct sock
*sk
, int bytes
);
373 void (*sk_write_space
)(struct sock
*sk
);
374 void (*sk_error_report
)(struct sock
*sk
);
375 int (*sk_backlog_rcv
)(struct sock
*sk
,
376 struct sk_buff
*skb
);
377 void (*sk_destruct
)(struct sock
*sk
);
380 static inline int sk_peek_offset(struct sock
*sk
, int flags
)
382 if ((flags
& MSG_PEEK
) && (sk
->sk_peek_off
>= 0))
383 return sk
->sk_peek_off
;
388 static inline void sk_peek_offset_bwd(struct sock
*sk
, int val
)
390 if (sk
->sk_peek_off
>= 0) {
391 if (sk
->sk_peek_off
>= val
)
392 sk
->sk_peek_off
-= val
;
398 static inline void sk_peek_offset_fwd(struct sock
*sk
, int val
)
400 if (sk
->sk_peek_off
>= 0)
401 sk
->sk_peek_off
+= val
;
405 * Hashed lists helper routines
407 static inline struct sock
*sk_entry(const struct hlist_node
*node
)
409 return hlist_entry(node
, struct sock
, sk_node
);
412 static inline struct sock
*__sk_head(const struct hlist_head
*head
)
414 return hlist_entry(head
->first
, struct sock
, sk_node
);
417 static inline struct sock
*sk_head(const struct hlist_head
*head
)
419 return hlist_empty(head
) ? NULL
: __sk_head(head
);
422 static inline struct sock
*__sk_nulls_head(const struct hlist_nulls_head
*head
)
424 return hlist_nulls_entry(head
->first
, struct sock
, sk_nulls_node
);
427 static inline struct sock
*sk_nulls_head(const struct hlist_nulls_head
*head
)
429 return hlist_nulls_empty(head
) ? NULL
: __sk_nulls_head(head
);
432 static inline struct sock
*sk_next(const struct sock
*sk
)
434 return sk
->sk_node
.next
?
435 hlist_entry(sk
->sk_node
.next
, struct sock
, sk_node
) : NULL
;
438 static inline struct sock
*sk_nulls_next(const struct sock
*sk
)
440 return (!is_a_nulls(sk
->sk_nulls_node
.next
)) ?
441 hlist_nulls_entry(sk
->sk_nulls_node
.next
,
442 struct sock
, sk_nulls_node
) :
446 static inline int sk_unhashed(const struct sock
*sk
)
448 return hlist_unhashed(&sk
->sk_node
);
451 static inline int sk_hashed(const struct sock
*sk
)
453 return !sk_unhashed(sk
);
456 static __inline__
void sk_node_init(struct hlist_node
*node
)
461 static __inline__
void sk_nulls_node_init(struct hlist_nulls_node
*node
)
466 static __inline__
void __sk_del_node(struct sock
*sk
)
468 __hlist_del(&sk
->sk_node
);
471 /* NB: equivalent to hlist_del_init_rcu */
472 static __inline__
int __sk_del_node_init(struct sock
*sk
)
476 sk_node_init(&sk
->sk_node
);
482 /* Grab socket reference count. This operation is valid only
483 when sk is ALREADY grabbed f.e. it is found in hash table
484 or a list and the lookup is made under lock preventing hash table
488 static inline void sock_hold(struct sock
*sk
)
490 atomic_inc(&sk
->sk_refcnt
);
493 /* Ungrab socket in the context, which assumes that socket refcnt
494 cannot hit zero, f.e. it is true in context of any socketcall.
496 static inline void __sock_put(struct sock
*sk
)
498 atomic_dec(&sk
->sk_refcnt
);
501 static __inline__
int sk_del_node_init(struct sock
*sk
)
503 int rc
= __sk_del_node_init(sk
);
506 /* paranoid for a while -acme */
507 WARN_ON(atomic_read(&sk
->sk_refcnt
) == 1);
512 #define sk_del_node_init_rcu(sk) sk_del_node_init(sk)
514 static __inline__
int __sk_nulls_del_node_init_rcu(struct sock
*sk
)
517 hlist_nulls_del_init_rcu(&sk
->sk_nulls_node
);
523 static __inline__
int sk_nulls_del_node_init_rcu(struct sock
*sk
)
525 int rc
= __sk_nulls_del_node_init_rcu(sk
);
528 /* paranoid for a while -acme */
529 WARN_ON(atomic_read(&sk
->sk_refcnt
) == 1);
535 static __inline__
void __sk_add_node(struct sock
*sk
, struct hlist_head
*list
)
537 hlist_add_head(&sk
->sk_node
, list
);
540 static __inline__
void sk_add_node(struct sock
*sk
, struct hlist_head
*list
)
543 __sk_add_node(sk
, list
);
546 static __inline__
void sk_add_node_rcu(struct sock
*sk
, struct hlist_head
*list
)
549 hlist_add_head_rcu(&sk
->sk_node
, list
);
552 static __inline__
void __sk_nulls_add_node_rcu(struct sock
*sk
, struct hlist_nulls_head
*list
)
554 hlist_nulls_add_head_rcu(&sk
->sk_nulls_node
, list
);
557 static __inline__
void sk_nulls_add_node_rcu(struct sock
*sk
, struct hlist_nulls_head
*list
)
560 __sk_nulls_add_node_rcu(sk
, list
);
563 static __inline__
void __sk_del_bind_node(struct sock
*sk
)
565 __hlist_del(&sk
->sk_bind_node
);
568 static __inline__
void sk_add_bind_node(struct sock
*sk
,
569 struct hlist_head
*list
)
571 hlist_add_head(&sk
->sk_bind_node
, list
);
574 #define sk_for_each(__sk, node, list) \
575 hlist_for_each_entry(__sk, node, list, sk_node)
576 #define sk_for_each_rcu(__sk, node, list) \
577 hlist_for_each_entry_rcu(__sk, node, list, sk_node)
578 #define sk_nulls_for_each(__sk, node, list) \
579 hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)
580 #define sk_nulls_for_each_rcu(__sk, node, list) \
581 hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)
582 #define sk_for_each_from(__sk, node) \
583 if (__sk && ({ node = &(__sk)->sk_node; 1; })) \
584 hlist_for_each_entry_from(__sk, node, sk_node)
585 #define sk_nulls_for_each_from(__sk, node) \
586 if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \
587 hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node)
588 #define sk_for_each_safe(__sk, node, tmp, list) \
589 hlist_for_each_entry_safe(__sk, node, tmp, list, sk_node)
590 #define sk_for_each_bound(__sk, node, list) \
591 hlist_for_each_entry(__sk, node, list, sk_bind_node)
604 SOCK_USE_WRITE_QUEUE
, /* whether to call sk->sk_write_space in sock_wfree */
605 SOCK_DBG
, /* %SO_DEBUG setting */
606 SOCK_RCVTSTAMP
, /* %SO_TIMESTAMP setting */
607 SOCK_RCVTSTAMPNS
, /* %SO_TIMESTAMPNS setting */
608 SOCK_LOCALROUTE
, /* route locally only, %SO_DONTROUTE setting */
609 SOCK_QUEUE_SHRUNK
, /* write queue has been shrunk recently */
610 SOCK_TIMESTAMPING_TX_HARDWARE
, /* %SOF_TIMESTAMPING_TX_HARDWARE */
611 SOCK_TIMESTAMPING_TX_SOFTWARE
, /* %SOF_TIMESTAMPING_TX_SOFTWARE */
612 SOCK_TIMESTAMPING_RX_HARDWARE
, /* %SOF_TIMESTAMPING_RX_HARDWARE */
613 SOCK_TIMESTAMPING_RX_SOFTWARE
, /* %SOF_TIMESTAMPING_RX_SOFTWARE */
614 SOCK_TIMESTAMPING_SOFTWARE
, /* %SOF_TIMESTAMPING_SOFTWARE */
615 SOCK_TIMESTAMPING_RAW_HARDWARE
, /* %SOF_TIMESTAMPING_RAW_HARDWARE */
616 SOCK_TIMESTAMPING_SYS_HARDWARE
, /* %SOF_TIMESTAMPING_SYS_HARDWARE */
617 SOCK_FASYNC
, /* fasync() active */
619 SOCK_ZEROCOPY
, /* buffers from userspace */
620 SOCK_WIFI_STATUS
, /* push wifi status to userspace */
621 SOCK_NOFCS
, /* Tell NIC not to do the Ethernet FCS.
622 * Will use last 4 bytes of packet sent from
623 * user-space instead.
627 static inline void sock_copy_flags(struct sock
*nsk
, struct sock
*osk
)
629 nsk
->sk_flags
= osk
->sk_flags
;
632 static inline void sock_set_flag(struct sock
*sk
, enum sock_flags flag
)
634 __set_bit(flag
, &sk
->sk_flags
);
637 static inline void sock_reset_flag(struct sock
*sk
, enum sock_flags flag
)
639 __clear_bit(flag
, &sk
->sk_flags
);
642 static inline int sock_flag(struct sock
*sk
, enum sock_flags flag
)
644 return test_bit(flag
, &sk
->sk_flags
);
647 static inline void sk_acceptq_removed(struct sock
*sk
)
649 sk
->sk_ack_backlog
--;
652 static inline void sk_acceptq_added(struct sock
*sk
)
654 sk
->sk_ack_backlog
++;
657 static inline int sk_acceptq_is_full(struct sock
*sk
)
659 return sk
->sk_ack_backlog
> sk
->sk_max_ack_backlog
;
663 * Compute minimal free write space needed to queue new packets.
665 static inline int sk_stream_min_wspace(struct sock
*sk
)
667 return sk
->sk_wmem_queued
>> 1;
670 static inline int sk_stream_wspace(struct sock
*sk
)
672 return sk
->sk_sndbuf
- sk
->sk_wmem_queued
;
675 extern void sk_stream_write_space(struct sock
*sk
);
677 static inline int sk_stream_memory_free(struct sock
*sk
)
679 return sk
->sk_wmem_queued
< sk
->sk_sndbuf
;
682 /* OOB backlog add */
683 static inline void __sk_add_backlog(struct sock
*sk
, struct sk_buff
*skb
)
685 /* dont let skb dst not refcounted, we are going to leave rcu lock */
688 if (!sk
->sk_backlog
.tail
)
689 sk
->sk_backlog
.head
= skb
;
691 sk
->sk_backlog
.tail
->next
= skb
;
693 sk
->sk_backlog
.tail
= skb
;
698 * Take into account size of receive queue and backlog queue
699 * Do not take into account this skb truesize,
700 * to allow even a single big packet to come.
702 static inline bool sk_rcvqueues_full(const struct sock
*sk
, const struct sk_buff
*skb
)
704 unsigned int qsize
= sk
->sk_backlog
.len
+ atomic_read(&sk
->sk_rmem_alloc
);
706 return qsize
> sk
->sk_rcvbuf
;
709 /* The per-socket spinlock must be held here. */
710 static inline __must_check
int sk_add_backlog(struct sock
*sk
, struct sk_buff
*skb
)
712 if (sk_rcvqueues_full(sk
, skb
))
715 __sk_add_backlog(sk
, skb
);
716 sk
->sk_backlog
.len
+= skb
->truesize
;
720 static inline int sk_backlog_rcv(struct sock
*sk
, struct sk_buff
*skb
)
722 return sk
->sk_backlog_rcv(sk
, skb
);
725 static inline void sock_rps_record_flow(const struct sock
*sk
)
728 struct rps_sock_flow_table
*sock_flow_table
;
731 sock_flow_table
= rcu_dereference(rps_sock_flow_table
);
732 rps_record_sock_flow(sock_flow_table
, sk
->sk_rxhash
);
737 static inline void sock_rps_reset_flow(const struct sock
*sk
)
740 struct rps_sock_flow_table
*sock_flow_table
;
743 sock_flow_table
= rcu_dereference(rps_sock_flow_table
);
744 rps_reset_sock_flow(sock_flow_table
, sk
->sk_rxhash
);
749 static inline void sock_rps_save_rxhash(struct sock
*sk
,
750 const struct sk_buff
*skb
)
753 if (unlikely(sk
->sk_rxhash
!= skb
->rxhash
)) {
754 sock_rps_reset_flow(sk
);
755 sk
->sk_rxhash
= skb
->rxhash
;
760 static inline void sock_rps_reset_rxhash(struct sock
*sk
)
763 sock_rps_reset_flow(sk
);
768 #define sk_wait_event(__sk, __timeo, __condition) \
770 release_sock(__sk); \
771 __rc = __condition; \
773 *(__timeo) = schedule_timeout(*(__timeo)); \
776 __rc = __condition; \
780 extern int sk_stream_wait_connect(struct sock
*sk
, long *timeo_p
);
781 extern int sk_stream_wait_memory(struct sock
*sk
, long *timeo_p
);
782 extern void sk_stream_wait_close(struct sock
*sk
, long timeo_p
);
783 extern int sk_stream_error(struct sock
*sk
, int flags
, int err
);
784 extern void sk_stream_kill_queues(struct sock
*sk
);
786 extern int sk_wait_data(struct sock
*sk
, long *timeo
);
788 struct request_sock_ops
;
789 struct timewait_sock_ops
;
790 struct inet_hashinfo
;
794 /* Networking protocol blocks we attach to sockets.
795 * socket layer -> transport layer interface
796 * transport -> network interface is defined by struct inet_proto
799 void (*close
)(struct sock
*sk
,
801 int (*connect
)(struct sock
*sk
,
802 struct sockaddr
*uaddr
,
804 int (*disconnect
)(struct sock
*sk
, int flags
);
806 struct sock
* (*accept
) (struct sock
*sk
, int flags
, int *err
);
808 int (*ioctl
)(struct sock
*sk
, int cmd
,
810 int (*init
)(struct sock
*sk
);
811 void (*destroy
)(struct sock
*sk
);
812 void (*shutdown
)(struct sock
*sk
, int how
);
813 int (*setsockopt
)(struct sock
*sk
, int level
,
814 int optname
, char __user
*optval
,
815 unsigned int optlen
);
816 int (*getsockopt
)(struct sock
*sk
, int level
,
817 int optname
, char __user
*optval
,
820 int (*compat_setsockopt
)(struct sock
*sk
,
822 int optname
, char __user
*optval
,
823 unsigned int optlen
);
824 int (*compat_getsockopt
)(struct sock
*sk
,
826 int optname
, char __user
*optval
,
828 int (*compat_ioctl
)(struct sock
*sk
,
829 unsigned int cmd
, unsigned long arg
);
831 int (*sendmsg
)(struct kiocb
*iocb
, struct sock
*sk
,
832 struct msghdr
*msg
, size_t len
);
833 int (*recvmsg
)(struct kiocb
*iocb
, struct sock
*sk
,
835 size_t len
, int noblock
, int flags
,
837 int (*sendpage
)(struct sock
*sk
, struct page
*page
,
838 int offset
, size_t size
, int flags
);
839 int (*bind
)(struct sock
*sk
,
840 struct sockaddr
*uaddr
, int addr_len
);
842 int (*backlog_rcv
) (struct sock
*sk
,
843 struct sk_buff
*skb
);
845 /* Keeping track of sk's, looking them up, and port selection methods. */
846 void (*hash
)(struct sock
*sk
);
847 void (*unhash
)(struct sock
*sk
);
848 void (*rehash
)(struct sock
*sk
);
849 int (*get_port
)(struct sock
*sk
, unsigned short snum
);
850 void (*clear_sk
)(struct sock
*sk
, int size
);
852 /* Keeping track of sockets in use */
853 #ifdef CONFIG_PROC_FS
854 unsigned int inuse_idx
;
857 /* Memory pressure */
858 void (*enter_memory_pressure
)(struct sock
*sk
);
859 atomic_long_t
*memory_allocated
; /* Current allocated memory. */
860 struct percpu_counter
*sockets_allocated
; /* Current number of sockets. */
862 * Pressure flag: try to collapse.
863 * Technical note: it is used by multiple contexts non atomically.
864 * All the __sk_mem_schedule() is of this nature: accounting
865 * is strict, actions are advisory and have some latency.
867 int *memory_pressure
;
874 struct kmem_cache
*slab
;
875 unsigned int obj_size
;
878 struct percpu_counter
*orphan_count
;
880 struct request_sock_ops
*rsk_prot
;
881 struct timewait_sock_ops
*twsk_prot
;
884 struct inet_hashinfo
*hashinfo
;
885 struct udp_table
*udp_table
;
886 struct raw_hashinfo
*raw_hash
;
889 struct module
*owner
;
893 struct list_head node
;
894 #ifdef SOCK_REFCNT_DEBUG
897 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_KMEM
899 * cgroup specific init/deinit functions. Called once for all
900 * protocols that implement it, from cgroups populate function.
901 * This function has to setup any files the protocol want to
902 * appear in the kmem cgroup filesystem.
904 int (*init_cgroup
)(struct cgroup
*cgrp
,
905 struct cgroup_subsys
*ss
);
906 void (*destroy_cgroup
)(struct cgroup
*cgrp
);
907 struct cg_proto
*(*proto_cgroup
)(struct mem_cgroup
*memcg
);
912 void (*enter_memory_pressure
)(struct sock
*sk
);
913 struct res_counter
*memory_allocated
; /* Current allocated memory. */
914 struct percpu_counter
*sockets_allocated
; /* Current number of sockets. */
915 int *memory_pressure
;
918 * memcg field is used to find which memcg we belong directly
919 * Each memcg struct can hold more than one cg_proto, so container_of
922 * The elegant solution would be having an inverse function to
923 * proto_cgroup in struct proto, but that means polluting the structure
924 * for everybody, instead of just for memcg users.
926 struct mem_cgroup
*memcg
;
929 extern int proto_register(struct proto
*prot
, int alloc_slab
);
930 extern void proto_unregister(struct proto
*prot
);
932 #ifdef SOCK_REFCNT_DEBUG
933 static inline void sk_refcnt_debug_inc(struct sock
*sk
)
935 atomic_inc(&sk
->sk_prot
->socks
);
938 static inline void sk_refcnt_debug_dec(struct sock
*sk
)
940 atomic_dec(&sk
->sk_prot
->socks
);
941 printk(KERN_DEBUG
"%s socket %p released, %d are still alive\n",
942 sk
->sk_prot
->name
, sk
, atomic_read(&sk
->sk_prot
->socks
));
945 inline void sk_refcnt_debug_release(const struct sock
*sk
)
947 if (atomic_read(&sk
->sk_refcnt
) != 1)
948 printk(KERN_DEBUG
"Destruction of the %s socket %p delayed, refcnt=%d\n",
949 sk
->sk_prot
->name
, sk
, atomic_read(&sk
->sk_refcnt
));
951 #else /* SOCK_REFCNT_DEBUG */
952 #define sk_refcnt_debug_inc(sk) do { } while (0)
953 #define sk_refcnt_debug_dec(sk) do { } while (0)
954 #define sk_refcnt_debug_release(sk) do { } while (0)
955 #endif /* SOCK_REFCNT_DEBUG */
957 #if defined(CONFIG_CGROUP_MEM_RES_CTLR_KMEM) && defined(CONFIG_NET)
958 extern struct static_key memcg_socket_limit_enabled
;
959 static inline struct cg_proto
*parent_cg_proto(struct proto
*proto
,
960 struct cg_proto
*cg_proto
)
962 return proto
->proto_cgroup(parent_mem_cgroup(cg_proto
->memcg
));
964 #define mem_cgroup_sockets_enabled static_key_false(&memcg_socket_limit_enabled)
966 #define mem_cgroup_sockets_enabled 0
967 static inline struct cg_proto
*parent_cg_proto(struct proto
*proto
,
968 struct cg_proto
*cg_proto
)
975 static inline bool sk_has_memory_pressure(const struct sock
*sk
)
977 return sk
->sk_prot
->memory_pressure
!= NULL
;
980 static inline bool sk_under_memory_pressure(const struct sock
*sk
)
982 if (!sk
->sk_prot
->memory_pressure
)
985 if (mem_cgroup_sockets_enabled
&& sk
->sk_cgrp
)
986 return !!*sk
->sk_cgrp
->memory_pressure
;
988 return !!*sk
->sk_prot
->memory_pressure
;
991 static inline void sk_leave_memory_pressure(struct sock
*sk
)
993 int *memory_pressure
= sk
->sk_prot
->memory_pressure
;
995 if (!memory_pressure
)
998 if (*memory_pressure
)
999 *memory_pressure
= 0;
1001 if (mem_cgroup_sockets_enabled
&& sk
->sk_cgrp
) {
1002 struct cg_proto
*cg_proto
= sk
->sk_cgrp
;
1003 struct proto
*prot
= sk
->sk_prot
;
1005 for (; cg_proto
; cg_proto
= parent_cg_proto(prot
, cg_proto
))
1006 if (*cg_proto
->memory_pressure
)
1007 *cg_proto
->memory_pressure
= 0;
1012 static inline void sk_enter_memory_pressure(struct sock
*sk
)
1014 if (!sk
->sk_prot
->enter_memory_pressure
)
1017 if (mem_cgroup_sockets_enabled
&& sk
->sk_cgrp
) {
1018 struct cg_proto
*cg_proto
= sk
->sk_cgrp
;
1019 struct proto
*prot
= sk
->sk_prot
;
1021 for (; cg_proto
; cg_proto
= parent_cg_proto(prot
, cg_proto
))
1022 cg_proto
->enter_memory_pressure(sk
);
1025 sk
->sk_prot
->enter_memory_pressure(sk
);
1028 static inline long sk_prot_mem_limits(const struct sock
*sk
, int index
)
1030 long *prot
= sk
->sk_prot
->sysctl_mem
;
1031 if (mem_cgroup_sockets_enabled
&& sk
->sk_cgrp
)
1032 prot
= sk
->sk_cgrp
->sysctl_mem
;
1036 static inline void memcg_memory_allocated_add(struct cg_proto
*prot
,
1040 struct res_counter
*fail
;
1043 ret
= res_counter_charge_nofail(prot
->memory_allocated
,
1044 amt
<< PAGE_SHIFT
, &fail
);
1046 *parent_status
= OVER_LIMIT
;
1049 static inline void memcg_memory_allocated_sub(struct cg_proto
*prot
,
1052 res_counter_uncharge(prot
->memory_allocated
, amt
<< PAGE_SHIFT
);
1055 static inline u64
memcg_memory_allocated_read(struct cg_proto
*prot
)
1058 ret
= res_counter_read_u64(prot
->memory_allocated
, RES_USAGE
);
1059 return ret
>> PAGE_SHIFT
;
1063 sk_memory_allocated(const struct sock
*sk
)
1065 struct proto
*prot
= sk
->sk_prot
;
1066 if (mem_cgroup_sockets_enabled
&& sk
->sk_cgrp
)
1067 return memcg_memory_allocated_read(sk
->sk_cgrp
);
1069 return atomic_long_read(prot
->memory_allocated
);
1073 sk_memory_allocated_add(struct sock
*sk
, int amt
, int *parent_status
)
1075 struct proto
*prot
= sk
->sk_prot
;
1077 if (mem_cgroup_sockets_enabled
&& sk
->sk_cgrp
) {
1078 memcg_memory_allocated_add(sk
->sk_cgrp
, amt
, parent_status
);
1079 /* update the root cgroup regardless */
1080 atomic_long_add_return(amt
, prot
->memory_allocated
);
1081 return memcg_memory_allocated_read(sk
->sk_cgrp
);
1084 return atomic_long_add_return(amt
, prot
->memory_allocated
);
1088 sk_memory_allocated_sub(struct sock
*sk
, int amt
)
1090 struct proto
*prot
= sk
->sk_prot
;
1092 if (mem_cgroup_sockets_enabled
&& sk
->sk_cgrp
)
1093 memcg_memory_allocated_sub(sk
->sk_cgrp
, amt
);
1095 atomic_long_sub(amt
, prot
->memory_allocated
);
1098 static inline void sk_sockets_allocated_dec(struct sock
*sk
)
1100 struct proto
*prot
= sk
->sk_prot
;
1102 if (mem_cgroup_sockets_enabled
&& sk
->sk_cgrp
) {
1103 struct cg_proto
*cg_proto
= sk
->sk_cgrp
;
1105 for (; cg_proto
; cg_proto
= parent_cg_proto(prot
, cg_proto
))
1106 percpu_counter_dec(cg_proto
->sockets_allocated
);
1109 percpu_counter_dec(prot
->sockets_allocated
);
1112 static inline void sk_sockets_allocated_inc(struct sock
*sk
)
1114 struct proto
*prot
= sk
->sk_prot
;
1116 if (mem_cgroup_sockets_enabled
&& sk
->sk_cgrp
) {
1117 struct cg_proto
*cg_proto
= sk
->sk_cgrp
;
1119 for (; cg_proto
; cg_proto
= parent_cg_proto(prot
, cg_proto
))
1120 percpu_counter_inc(cg_proto
->sockets_allocated
);
1123 percpu_counter_inc(prot
->sockets_allocated
);
1127 sk_sockets_allocated_read_positive(struct sock
*sk
)
1129 struct proto
*prot
= sk
->sk_prot
;
1131 if (mem_cgroup_sockets_enabled
&& sk
->sk_cgrp
)
1132 return percpu_counter_sum_positive(sk
->sk_cgrp
->sockets_allocated
);
1134 return percpu_counter_sum_positive(prot
->sockets_allocated
);
1138 proto_sockets_allocated_sum_positive(struct proto
*prot
)
1140 return percpu_counter_sum_positive(prot
->sockets_allocated
);
1144 proto_memory_allocated(struct proto
*prot
)
1146 return atomic_long_read(prot
->memory_allocated
);
1150 proto_memory_pressure(struct proto
*prot
)
1152 if (!prot
->memory_pressure
)
1154 return !!*prot
->memory_pressure
;
1158 #ifdef CONFIG_PROC_FS
1159 /* Called with local bh disabled */
1160 extern void sock_prot_inuse_add(struct net
*net
, struct proto
*prot
, int inc
);
1161 extern int sock_prot_inuse_get(struct net
*net
, struct proto
*proto
);
1163 static void inline sock_prot_inuse_add(struct net
*net
, struct proto
*prot
,
1170 /* With per-bucket locks this operation is not-atomic, so that
1171 * this version is not worse.
1173 static inline void __sk_prot_rehash(struct sock
*sk
)
1175 sk
->sk_prot
->unhash(sk
);
1176 sk
->sk_prot
->hash(sk
);
1179 void sk_prot_clear_portaddr_nulls(struct sock
*sk
, int size
);
1181 /* About 10 seconds */
1182 #define SOCK_DESTROY_TIME (10*HZ)
1184 /* Sockets 0-1023 can't be bound to unless you are superuser */
1185 #define PROT_SOCK 1024
1187 #define SHUTDOWN_MASK 3
1188 #define RCV_SHUTDOWN 1
1189 #define SEND_SHUTDOWN 2
1191 #define SOCK_SNDBUF_LOCK 1
1192 #define SOCK_RCVBUF_LOCK 2
1193 #define SOCK_BINDADDR_LOCK 4
1194 #define SOCK_BINDPORT_LOCK 8
1196 /* sock_iocb: used to kick off async processing of socket ios */
1198 struct list_head list
;
1202 struct socket
*sock
;
1204 struct scm_cookie
*scm
;
1205 struct msghdr
*msg
, async_msg
;
1206 struct kiocb
*kiocb
;
1209 static inline struct sock_iocb
*kiocb_to_siocb(struct kiocb
*iocb
)
1211 return (struct sock_iocb
*)iocb
->private;
1214 static inline struct kiocb
*siocb_to_kiocb(struct sock_iocb
*si
)
1219 struct socket_alloc
{
1220 struct socket socket
;
1221 struct inode vfs_inode
;
1224 static inline struct socket
*SOCKET_I(struct inode
*inode
)
1226 return &container_of(inode
, struct socket_alloc
, vfs_inode
)->socket
;
1229 static inline struct inode
*SOCK_INODE(struct socket
*socket
)
1231 return &container_of(socket
, struct socket_alloc
, socket
)->vfs_inode
;
1235 * Functions for memory accounting
1237 extern int __sk_mem_schedule(struct sock
*sk
, int size
, int kind
);
1238 extern void __sk_mem_reclaim(struct sock
*sk
);
1240 #define SK_MEM_QUANTUM ((int)PAGE_SIZE)
1241 #define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM)
1242 #define SK_MEM_SEND 0
1243 #define SK_MEM_RECV 1
1245 static inline int sk_mem_pages(int amt
)
1247 return (amt
+ SK_MEM_QUANTUM
- 1) >> SK_MEM_QUANTUM_SHIFT
;
1250 static inline int sk_has_account(struct sock
*sk
)
1252 /* return true if protocol supports memory accounting */
1253 return !!sk
->sk_prot
->memory_allocated
;
1256 static inline int sk_wmem_schedule(struct sock
*sk
, int size
)
1258 if (!sk_has_account(sk
))
1260 return size
<= sk
->sk_forward_alloc
||
1261 __sk_mem_schedule(sk
, size
, SK_MEM_SEND
);
1264 static inline int sk_rmem_schedule(struct sock
*sk
, int size
)
1266 if (!sk_has_account(sk
))
1268 return size
<= sk
->sk_forward_alloc
||
1269 __sk_mem_schedule(sk
, size
, SK_MEM_RECV
);
1272 static inline void sk_mem_reclaim(struct sock
*sk
)
1274 if (!sk_has_account(sk
))
1276 if (sk
->sk_forward_alloc
>= SK_MEM_QUANTUM
)
1277 __sk_mem_reclaim(sk
);
1280 static inline void sk_mem_reclaim_partial(struct sock
*sk
)
1282 if (!sk_has_account(sk
))
1284 if (sk
->sk_forward_alloc
> SK_MEM_QUANTUM
)
1285 __sk_mem_reclaim(sk
);
1288 static inline void sk_mem_charge(struct sock
*sk
, int size
)
1290 if (!sk_has_account(sk
))
1292 sk
->sk_forward_alloc
-= size
;
1295 static inline void sk_mem_uncharge(struct sock
*sk
, int size
)
1297 if (!sk_has_account(sk
))
1299 sk
->sk_forward_alloc
+= size
;
1302 static inline void sk_wmem_free_skb(struct sock
*sk
, struct sk_buff
*skb
)
1304 sock_set_flag(sk
, SOCK_QUEUE_SHRUNK
);
1305 sk
->sk_wmem_queued
-= skb
->truesize
;
1306 sk_mem_uncharge(sk
, skb
->truesize
);
1310 /* Used by processes to "lock" a socket state, so that
1311 * interrupts and bottom half handlers won't change it
1312 * from under us. It essentially blocks any incoming
1313 * packets, so that we won't get any new data or any
1314 * packets that change the state of the socket.
1316 * While locked, BH processing will add new packets to
1317 * the backlog queue. This queue is processed by the
1318 * owner of the socket lock right before it is released.
1320 * Since ~2.3.5 it is also exclusive sleep lock serializing
1321 * accesses from user process context.
1323 #define sock_owned_by_user(sk) ((sk)->sk_lock.owned)
1326 * Macro so as to not evaluate some arguments when
1327 * lockdep is not enabled.
1329 * Mark both the sk_lock and the sk_lock.slock as a
1330 * per-address-family lock class.
1332 #define sock_lock_init_class_and_name(sk, sname, skey, name, key) \
1334 sk->sk_lock.owned = 0; \
1335 init_waitqueue_head(&sk->sk_lock.wq); \
1336 spin_lock_init(&(sk)->sk_lock.slock); \
1337 debug_check_no_locks_freed((void *)&(sk)->sk_lock, \
1338 sizeof((sk)->sk_lock)); \
1339 lockdep_set_class_and_name(&(sk)->sk_lock.slock, \
1341 lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \
1344 extern void lock_sock_nested(struct sock
*sk
, int subclass
);
1346 static inline void lock_sock(struct sock
*sk
)
1348 lock_sock_nested(sk
, 0);
1351 extern void release_sock(struct sock
*sk
);
1353 /* BH context may only use the following locking interface. */
1354 #define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock))
1355 #define bh_lock_sock_nested(__sk) \
1356 spin_lock_nested(&((__sk)->sk_lock.slock), \
1357 SINGLE_DEPTH_NESTING)
1358 #define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock))
1360 extern bool lock_sock_fast(struct sock
*sk
);
1362 * unlock_sock_fast - complement of lock_sock_fast
1366 * fast unlock socket for user context.
1367 * If slow mode is on, we call regular release_sock()
1369 static inline void unlock_sock_fast(struct sock
*sk
, bool slow
)
1374 spin_unlock_bh(&sk
->sk_lock
.slock
);
1378 extern struct sock
*sk_alloc(struct net
*net
, int family
,
1380 struct proto
*prot
);
1381 extern void sk_free(struct sock
*sk
);
1382 extern void sk_release_kernel(struct sock
*sk
);
1383 extern struct sock
*sk_clone_lock(const struct sock
*sk
,
1384 const gfp_t priority
);
1386 extern struct sk_buff
*sock_wmalloc(struct sock
*sk
,
1387 unsigned long size
, int force
,
1389 extern struct sk_buff
*sock_rmalloc(struct sock
*sk
,
1390 unsigned long size
, int force
,
1392 extern void sock_wfree(struct sk_buff
*skb
);
1393 extern void sock_rfree(struct sk_buff
*skb
);
1395 extern int sock_setsockopt(struct socket
*sock
, int level
,
1396 int op
, char __user
*optval
,
1397 unsigned int optlen
);
1399 extern int sock_getsockopt(struct socket
*sock
, int level
,
1400 int op
, char __user
*optval
,
1401 int __user
*optlen
);
1402 extern struct sk_buff
*sock_alloc_send_skb(struct sock
*sk
,
1406 extern struct sk_buff
*sock_alloc_send_pskb(struct sock
*sk
,
1407 unsigned long header_len
,
1408 unsigned long data_len
,
1411 extern void *sock_kmalloc(struct sock
*sk
, int size
,
1413 extern void sock_kfree_s(struct sock
*sk
, void *mem
, int size
);
1414 extern void sk_send_sigurg(struct sock
*sk
);
1416 #ifdef CONFIG_CGROUPS
1417 extern void sock_update_classid(struct sock
*sk
);
1419 static inline void sock_update_classid(struct sock
*sk
)
1425 * Functions to fill in entries in struct proto_ops when a protocol
1426 * does not implement a particular function.
1428 extern int sock_no_bind(struct socket
*,
1429 struct sockaddr
*, int);
1430 extern int sock_no_connect(struct socket
*,
1431 struct sockaddr
*, int, int);
1432 extern int sock_no_socketpair(struct socket
*,
1434 extern int sock_no_accept(struct socket
*,
1435 struct socket
*, int);
1436 extern int sock_no_getname(struct socket
*,
1437 struct sockaddr
*, int *, int);
1438 extern unsigned int sock_no_poll(struct file
*, struct socket
*,
1439 struct poll_table_struct
*);
1440 extern int sock_no_ioctl(struct socket
*, unsigned int,
1442 extern int sock_no_listen(struct socket
*, int);
1443 extern int sock_no_shutdown(struct socket
*, int);
1444 extern int sock_no_getsockopt(struct socket
*, int , int,
1445 char __user
*, int __user
*);
1446 extern int sock_no_setsockopt(struct socket
*, int, int,
1447 char __user
*, unsigned int);
1448 extern int sock_no_sendmsg(struct kiocb
*, struct socket
*,
1449 struct msghdr
*, size_t);
1450 extern int sock_no_recvmsg(struct kiocb
*, struct socket
*,
1451 struct msghdr
*, size_t, int);
1452 extern int sock_no_mmap(struct file
*file
,
1453 struct socket
*sock
,
1454 struct vm_area_struct
*vma
);
1455 extern ssize_t
sock_no_sendpage(struct socket
*sock
,
1457 int offset
, size_t size
,
1461 * Functions to fill in entries in struct proto_ops when a protocol
1462 * uses the inet style.
1464 extern int sock_common_getsockopt(struct socket
*sock
, int level
, int optname
,
1465 char __user
*optval
, int __user
*optlen
);
1466 extern int sock_common_recvmsg(struct kiocb
*iocb
, struct socket
*sock
,
1467 struct msghdr
*msg
, size_t size
, int flags
);
1468 extern int sock_common_setsockopt(struct socket
*sock
, int level
, int optname
,
1469 char __user
*optval
, unsigned int optlen
);
1470 extern int compat_sock_common_getsockopt(struct socket
*sock
, int level
,
1471 int optname
, char __user
*optval
, int __user
*optlen
);
1472 extern int compat_sock_common_setsockopt(struct socket
*sock
, int level
,
1473 int optname
, char __user
*optval
, unsigned int optlen
);
1475 extern void sk_common_release(struct sock
*sk
);
1478 * Default socket callbacks and setup code
1481 /* Initialise core socket variables */
1482 extern void sock_init_data(struct socket
*sock
, struct sock
*sk
);
1484 extern void sk_filter_release_rcu(struct rcu_head
*rcu
);
1487 * sk_filter_release - release a socket filter
1488 * @fp: filter to remove
1490 * Remove a filter from a socket and release its resources.
1493 static inline void sk_filter_release(struct sk_filter
*fp
)
1495 if (atomic_dec_and_test(&fp
->refcnt
))
1496 call_rcu(&fp
->rcu
, sk_filter_release_rcu
);
1499 static inline void sk_filter_uncharge(struct sock
*sk
, struct sk_filter
*fp
)
1501 unsigned int size
= sk_filter_len(fp
);
1503 atomic_sub(size
, &sk
->sk_omem_alloc
);
1504 sk_filter_release(fp
);
1507 static inline void sk_filter_charge(struct sock
*sk
, struct sk_filter
*fp
)
1509 atomic_inc(&fp
->refcnt
);
1510 atomic_add(sk_filter_len(fp
), &sk
->sk_omem_alloc
);
1514 * Socket reference counting postulates.
1516 * * Each user of socket SHOULD hold a reference count.
1517 * * Each access point to socket (an hash table bucket, reference from a list,
1518 * running timer, skb in flight MUST hold a reference count.
1519 * * When reference count hits 0, it means it will never increase back.
1520 * * When reference count hits 0, it means that no references from
1521 * outside exist to this socket and current process on current CPU
1522 * is last user and may/should destroy this socket.
1523 * * sk_free is called from any context: process, BH, IRQ. When
1524 * it is called, socket has no references from outside -> sk_free
1525 * may release descendant resources allocated by the socket, but
1526 * to the time when it is called, socket is NOT referenced by any
1527 * hash tables, lists etc.
1528 * * Packets, delivered from outside (from network or from another process)
1529 * and enqueued on receive/error queues SHOULD NOT grab reference count,
1530 * when they sit in queue. Otherwise, packets will leak to hole, when
1531 * socket is looked up by one cpu and unhasing is made by another CPU.
1532 * It is true for udp/raw, netlink (leak to receive and error queues), tcp
1533 * (leak to backlog). Packet socket does all the processing inside
1534 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
1535 * use separate SMP lock, so that they are prone too.
1538 /* Ungrab socket and destroy it, if it was the last reference. */
1539 static inline void sock_put(struct sock
*sk
)
1541 if (atomic_dec_and_test(&sk
->sk_refcnt
))
1545 extern int sk_receive_skb(struct sock
*sk
, struct sk_buff
*skb
,
1548 static inline void sk_tx_queue_set(struct sock
*sk
, int tx_queue
)
1550 sk
->sk_tx_queue_mapping
= tx_queue
;
1553 static inline void sk_tx_queue_clear(struct sock
*sk
)
1555 sk
->sk_tx_queue_mapping
= -1;
1558 static inline int sk_tx_queue_get(const struct sock
*sk
)
1560 return sk
? sk
->sk_tx_queue_mapping
: -1;
1563 static inline void sk_set_socket(struct sock
*sk
, struct socket
*sock
)
1565 sk_tx_queue_clear(sk
);
1566 sk
->sk_socket
= sock
;
1569 static inline wait_queue_head_t
*sk_sleep(struct sock
*sk
)
1571 BUILD_BUG_ON(offsetof(struct socket_wq
, wait
) != 0);
1572 return &rcu_dereference_raw(sk
->sk_wq
)->wait
;
1574 /* Detach socket from process context.
1575 * Announce socket dead, detach it from wait queue and inode.
1576 * Note that parent inode held reference count on this struct sock,
1577 * we do not release it in this function, because protocol
1578 * probably wants some additional cleanups or even continuing
1579 * to work with this socket (TCP).
1581 static inline void sock_orphan(struct sock
*sk
)
1583 write_lock_bh(&sk
->sk_callback_lock
);
1584 sock_set_flag(sk
, SOCK_DEAD
);
1585 sk_set_socket(sk
, NULL
);
1587 write_unlock_bh(&sk
->sk_callback_lock
);
1590 static inline void sock_graft(struct sock
*sk
, struct socket
*parent
)
1592 write_lock_bh(&sk
->sk_callback_lock
);
1593 sk
->sk_wq
= parent
->wq
;
1595 sk_set_socket(sk
, parent
);
1596 security_sock_graft(sk
, parent
);
1597 write_unlock_bh(&sk
->sk_callback_lock
);
1600 extern int sock_i_uid(struct sock
*sk
);
1601 extern unsigned long sock_i_ino(struct sock
*sk
);
1603 static inline struct dst_entry
*
1604 __sk_dst_get(struct sock
*sk
)
1606 return rcu_dereference_check(sk
->sk_dst_cache
, sock_owned_by_user(sk
) ||
1607 lockdep_is_held(&sk
->sk_lock
.slock
));
1610 static inline struct dst_entry
*
1611 sk_dst_get(struct sock
*sk
)
1613 struct dst_entry
*dst
;
1616 dst
= rcu_dereference(sk
->sk_dst_cache
);
1623 extern void sk_reset_txq(struct sock
*sk
);
1625 static inline void dst_negative_advice(struct sock
*sk
)
1627 struct dst_entry
*ndst
, *dst
= __sk_dst_get(sk
);
1629 if (dst
&& dst
->ops
->negative_advice
) {
1630 ndst
= dst
->ops
->negative_advice(dst
);
1633 rcu_assign_pointer(sk
->sk_dst_cache
, ndst
);
1640 __sk_dst_set(struct sock
*sk
, struct dst_entry
*dst
)
1642 struct dst_entry
*old_dst
;
1644 sk_tx_queue_clear(sk
);
1646 * This can be called while sk is owned by the caller only,
1647 * with no state that can be checked in a rcu_dereference_check() cond
1649 old_dst
= rcu_dereference_raw(sk
->sk_dst_cache
);
1650 rcu_assign_pointer(sk
->sk_dst_cache
, dst
);
1651 dst_release(old_dst
);
1655 sk_dst_set(struct sock
*sk
, struct dst_entry
*dst
)
1657 spin_lock(&sk
->sk_dst_lock
);
1658 __sk_dst_set(sk
, dst
);
1659 spin_unlock(&sk
->sk_dst_lock
);
1663 __sk_dst_reset(struct sock
*sk
)
1665 __sk_dst_set(sk
, NULL
);
1669 sk_dst_reset(struct sock
*sk
)
1671 spin_lock(&sk
->sk_dst_lock
);
1673 spin_unlock(&sk
->sk_dst_lock
);
1676 extern struct dst_entry
*__sk_dst_check(struct sock
*sk
, u32 cookie
);
1678 extern struct dst_entry
*sk_dst_check(struct sock
*sk
, u32 cookie
);
1680 static inline int sk_can_gso(const struct sock
*sk
)
1682 return net_gso_ok(sk
->sk_route_caps
, sk
->sk_gso_type
);
1685 extern void sk_setup_caps(struct sock
*sk
, struct dst_entry
*dst
);
1687 static inline void sk_nocaps_add(struct sock
*sk
, netdev_features_t flags
)
1689 sk
->sk_route_nocaps
|= flags
;
1690 sk
->sk_route_caps
&= ~flags
;
1693 static inline int skb_do_copy_data_nocache(struct sock
*sk
, struct sk_buff
*skb
,
1694 char __user
*from
, char *to
,
1695 int copy
, int offset
)
1697 if (skb
->ip_summed
== CHECKSUM_NONE
) {
1699 __wsum csum
= csum_and_copy_from_user(from
, to
, copy
, 0, &err
);
1702 skb
->csum
= csum_block_add(skb
->csum
, csum
, offset
);
1703 } else if (sk
->sk_route_caps
& NETIF_F_NOCACHE_COPY
) {
1704 if (!access_ok(VERIFY_READ
, from
, copy
) ||
1705 __copy_from_user_nocache(to
, from
, copy
))
1707 } else if (copy_from_user(to
, from
, copy
))
1713 static inline int skb_add_data_nocache(struct sock
*sk
, struct sk_buff
*skb
,
1714 char __user
*from
, int copy
)
1716 int err
, offset
= skb
->len
;
1718 err
= skb_do_copy_data_nocache(sk
, skb
, from
, skb_put(skb
, copy
),
1721 __skb_trim(skb
, offset
);
1726 static inline int skb_copy_to_page_nocache(struct sock
*sk
, char __user
*from
,
1727 struct sk_buff
*skb
,
1733 err
= skb_do_copy_data_nocache(sk
, skb
, from
, page_address(page
) + off
,
1739 skb
->data_len
+= copy
;
1740 skb
->truesize
+= copy
;
1741 sk
->sk_wmem_queued
+= copy
;
1742 sk_mem_charge(sk
, copy
);
1746 static inline int skb_copy_to_page(struct sock
*sk
, char __user
*from
,
1747 struct sk_buff
*skb
, struct page
*page
,
1750 if (skb
->ip_summed
== CHECKSUM_NONE
) {
1752 __wsum csum
= csum_and_copy_from_user(from
,
1753 page_address(page
) + off
,
1757 skb
->csum
= csum_block_add(skb
->csum
, csum
, skb
->len
);
1758 } else if (copy_from_user(page_address(page
) + off
, from
, copy
))
1762 skb
->data_len
+= copy
;
1763 skb
->truesize
+= copy
;
1764 sk
->sk_wmem_queued
+= copy
;
1765 sk_mem_charge(sk
, copy
);
1770 * sk_wmem_alloc_get - returns write allocations
1773 * Returns sk_wmem_alloc minus initial offset of one
1775 static inline int sk_wmem_alloc_get(const struct sock
*sk
)
1777 return atomic_read(&sk
->sk_wmem_alloc
) - 1;
1781 * sk_rmem_alloc_get - returns read allocations
1784 * Returns sk_rmem_alloc
1786 static inline int sk_rmem_alloc_get(const struct sock
*sk
)
1788 return atomic_read(&sk
->sk_rmem_alloc
);
1792 * sk_has_allocations - check if allocations are outstanding
1795 * Returns true if socket has write or read allocations
1797 static inline int sk_has_allocations(const struct sock
*sk
)
1799 return sk_wmem_alloc_get(sk
) || sk_rmem_alloc_get(sk
);
1803 * wq_has_sleeper - check if there are any waiting processes
1804 * @wq: struct socket_wq
1806 * Returns true if socket_wq has waiting processes
1808 * The purpose of the wq_has_sleeper and sock_poll_wait is to wrap the memory
1809 * barrier call. They were added due to the race found within the tcp code.
1811 * Consider following tcp code paths:
1815 * sys_select receive packet
1817 * __add_wait_queue update tp->rcv_nxt
1819 * tp->rcv_nxt check sock_def_readable
1821 * schedule rcu_read_lock();
1822 * wq = rcu_dereference(sk->sk_wq);
1823 * if (wq && waitqueue_active(&wq->wait))
1824 * wake_up_interruptible(&wq->wait)
1828 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
1829 * in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1
1830 * could then endup calling schedule and sleep forever if there are no more
1831 * data on the socket.
1834 static inline bool wq_has_sleeper(struct socket_wq
*wq
)
1838 * We need to be sure we are in sync with the
1839 * add_wait_queue modifications to the wait queue.
1841 * This memory barrier is paired in the sock_poll_wait.
1844 return wq
&& waitqueue_active(&wq
->wait
);
1848 * sock_poll_wait - place memory barrier behind the poll_wait call.
1850 * @wait_address: socket wait queue
1853 * See the comments in the wq_has_sleeper function.
1855 static inline void sock_poll_wait(struct file
*filp
,
1856 wait_queue_head_t
*wait_address
, poll_table
*p
)
1858 if (!poll_does_not_wait(p
) && wait_address
) {
1859 poll_wait(filp
, wait_address
, p
);
1861 * We need to be sure we are in sync with the
1862 * socket flags modification.
1864 * This memory barrier is paired in the wq_has_sleeper.
1871 * Queue a received datagram if it will fit. Stream and sequenced
1872 * protocols can't normally use this as they need to fit buffers in
1873 * and play with them.
1875 * Inlined as it's very short and called for pretty much every
1876 * packet ever received.
1879 static inline void skb_set_owner_w(struct sk_buff
*skb
, struct sock
*sk
)
1883 skb
->destructor
= sock_wfree
;
1885 * We used to take a refcount on sk, but following operation
1886 * is enough to guarantee sk_free() wont free this sock until
1887 * all in-flight packets are completed
1889 atomic_add(skb
->truesize
, &sk
->sk_wmem_alloc
);
1892 static inline void skb_set_owner_r(struct sk_buff
*skb
, struct sock
*sk
)
1896 skb
->destructor
= sock_rfree
;
1897 atomic_add(skb
->truesize
, &sk
->sk_rmem_alloc
);
1898 sk_mem_charge(sk
, skb
->truesize
);
1901 extern void sk_reset_timer(struct sock
*sk
, struct timer_list
* timer
,
1902 unsigned long expires
);
1904 extern void sk_stop_timer(struct sock
*sk
, struct timer_list
* timer
);
1906 extern int sock_queue_rcv_skb(struct sock
*sk
, struct sk_buff
*skb
);
1908 extern int sock_queue_err_skb(struct sock
*sk
, struct sk_buff
*skb
);
1911 * Recover an error report and clear atomically
1914 static inline int sock_error(struct sock
*sk
)
1917 if (likely(!sk
->sk_err
))
1919 err
= xchg(&sk
->sk_err
, 0);
1923 static inline unsigned long sock_wspace(struct sock
*sk
)
1927 if (!(sk
->sk_shutdown
& SEND_SHUTDOWN
)) {
1928 amt
= sk
->sk_sndbuf
- atomic_read(&sk
->sk_wmem_alloc
);
1935 static inline void sk_wake_async(struct sock
*sk
, int how
, int band
)
1937 if (sock_flag(sk
, SOCK_FASYNC
))
1938 sock_wake_async(sk
->sk_socket
, how
, band
);
1941 #define SOCK_MIN_SNDBUF 2048
1943 * Since sk_rmem_alloc sums skb->truesize, even a small frame might need
1944 * sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak
1946 #define SOCK_MIN_RCVBUF (2048 + sizeof(struct sk_buff))
1948 static inline void sk_stream_moderate_sndbuf(struct sock
*sk
)
1950 if (!(sk
->sk_userlocks
& SOCK_SNDBUF_LOCK
)) {
1951 sk
->sk_sndbuf
= min(sk
->sk_sndbuf
, sk
->sk_wmem_queued
>> 1);
1952 sk
->sk_sndbuf
= max(sk
->sk_sndbuf
, SOCK_MIN_SNDBUF
);
1956 struct sk_buff
*sk_stream_alloc_skb(struct sock
*sk
, int size
, gfp_t gfp
);
1958 static inline struct page
*sk_stream_alloc_page(struct sock
*sk
)
1960 struct page
*page
= NULL
;
1962 page
= alloc_pages(sk
->sk_allocation
, 0);
1964 sk_enter_memory_pressure(sk
);
1965 sk_stream_moderate_sndbuf(sk
);
1971 * Default write policy as shown to user space via poll/select/SIGIO
1973 static inline int sock_writeable(const struct sock
*sk
)
1975 return atomic_read(&sk
->sk_wmem_alloc
) < (sk
->sk_sndbuf
>> 1);
1978 static inline gfp_t
gfp_any(void)
1980 return in_softirq() ? GFP_ATOMIC
: GFP_KERNEL
;
1983 static inline long sock_rcvtimeo(const struct sock
*sk
, int noblock
)
1985 return noblock
? 0 : sk
->sk_rcvtimeo
;
1988 static inline long sock_sndtimeo(const struct sock
*sk
, int noblock
)
1990 return noblock
? 0 : sk
->sk_sndtimeo
;
1993 static inline int sock_rcvlowat(const struct sock
*sk
, int waitall
, int len
)
1995 return (waitall
? len
: min_t(int, sk
->sk_rcvlowat
, len
)) ? : 1;
1998 /* Alas, with timeout socket operations are not restartable.
1999 * Compare this to poll().
2001 static inline int sock_intr_errno(long timeo
)
2003 return timeo
== MAX_SCHEDULE_TIMEOUT
? -ERESTARTSYS
: -EINTR
;
2006 extern void __sock_recv_timestamp(struct msghdr
*msg
, struct sock
*sk
,
2007 struct sk_buff
*skb
);
2008 extern void __sock_recv_wifi_status(struct msghdr
*msg
, struct sock
*sk
,
2009 struct sk_buff
*skb
);
2011 static __inline__
void
2012 sock_recv_timestamp(struct msghdr
*msg
, struct sock
*sk
, struct sk_buff
*skb
)
2014 ktime_t kt
= skb
->tstamp
;
2015 struct skb_shared_hwtstamps
*hwtstamps
= skb_hwtstamps(skb
);
2018 * generate control messages if
2019 * - receive time stamping in software requested (SOCK_RCVTSTAMP
2020 * or SOCK_TIMESTAMPING_RX_SOFTWARE)
2021 * - software time stamp available and wanted
2022 * (SOCK_TIMESTAMPING_SOFTWARE)
2023 * - hardware time stamps available and wanted
2024 * (SOCK_TIMESTAMPING_SYS_HARDWARE or
2025 * SOCK_TIMESTAMPING_RAW_HARDWARE)
2027 if (sock_flag(sk
, SOCK_RCVTSTAMP
) ||
2028 sock_flag(sk
, SOCK_TIMESTAMPING_RX_SOFTWARE
) ||
2029 (kt
.tv64
&& sock_flag(sk
, SOCK_TIMESTAMPING_SOFTWARE
)) ||
2030 (hwtstamps
->hwtstamp
.tv64
&&
2031 sock_flag(sk
, SOCK_TIMESTAMPING_RAW_HARDWARE
)) ||
2032 (hwtstamps
->syststamp
.tv64
&&
2033 sock_flag(sk
, SOCK_TIMESTAMPING_SYS_HARDWARE
)))
2034 __sock_recv_timestamp(msg
, sk
, skb
);
2038 if (sock_flag(sk
, SOCK_WIFI_STATUS
) && skb
->wifi_acked_valid
)
2039 __sock_recv_wifi_status(msg
, sk
, skb
);
2042 extern void __sock_recv_ts_and_drops(struct msghdr
*msg
, struct sock
*sk
,
2043 struct sk_buff
*skb
);
2045 static inline void sock_recv_ts_and_drops(struct msghdr
*msg
, struct sock
*sk
,
2046 struct sk_buff
*skb
)
2048 #define FLAGS_TS_OR_DROPS ((1UL << SOCK_RXQ_OVFL) | \
2049 (1UL << SOCK_RCVTSTAMP) | \
2050 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE) | \
2051 (1UL << SOCK_TIMESTAMPING_SOFTWARE) | \
2052 (1UL << SOCK_TIMESTAMPING_RAW_HARDWARE) | \
2053 (1UL << SOCK_TIMESTAMPING_SYS_HARDWARE))
2055 if (sk
->sk_flags
& FLAGS_TS_OR_DROPS
)
2056 __sock_recv_ts_and_drops(msg
, sk
, skb
);
2058 sk
->sk_stamp
= skb
->tstamp
;
2062 * sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
2063 * @sk: socket sending this packet
2064 * @tx_flags: filled with instructions for time stamping
2066 * Currently only depends on SOCK_TIMESTAMPING* flags. Returns error code if
2067 * parameters are invalid.
2069 extern int sock_tx_timestamp(struct sock
*sk
, __u8
*tx_flags
);
2072 * sk_eat_skb - Release a skb if it is no longer needed
2073 * @sk: socket to eat this skb from
2074 * @skb: socket buffer to eat
2075 * @copied_early: flag indicating whether DMA operations copied this data early
2077 * This routine must be called with interrupts disabled or with the socket
2078 * locked so that the sk_buff queue operation is ok.
2080 #ifdef CONFIG_NET_DMA
2081 static inline void sk_eat_skb(struct sock
*sk
, struct sk_buff
*skb
, int copied_early
)
2083 __skb_unlink(skb
, &sk
->sk_receive_queue
);
2087 __skb_queue_tail(&sk
->sk_async_wait_queue
, skb
);
2090 static inline void sk_eat_skb(struct sock
*sk
, struct sk_buff
*skb
, int copied_early
)
2092 __skb_unlink(skb
, &sk
->sk_receive_queue
);
2098 struct net
*sock_net(const struct sock
*sk
)
2100 return read_pnet(&sk
->sk_net
);
2104 void sock_net_set(struct sock
*sk
, struct net
*net
)
2106 write_pnet(&sk
->sk_net
, net
);
2110 * Kernel sockets, f.e. rtnl or icmp_socket, are a part of a namespace.
2111 * They should not hold a reference to a namespace in order to allow
2113 * Sockets after sk_change_net should be released using sk_release_kernel
2115 static inline void sk_change_net(struct sock
*sk
, struct net
*net
)
2117 put_net(sock_net(sk
));
2118 sock_net_set(sk
, hold_net(net
));
2121 static inline struct sock
*skb_steal_sock(struct sk_buff
*skb
)
2123 if (unlikely(skb
->sk
)) {
2124 struct sock
*sk
= skb
->sk
;
2126 skb
->destructor
= NULL
;
2133 extern void sock_enable_timestamp(struct sock
*sk
, int flag
);
2134 extern int sock_get_timestamp(struct sock
*, struct timeval __user
*);
2135 extern int sock_get_timestampns(struct sock
*, struct timespec __user
*);
2138 * Enable debug/info messages
2140 extern int net_msg_warn
;
2141 #define NETDEBUG(fmt, args...) \
2142 do { if (net_msg_warn) printk(fmt,##args); } while (0)
2144 #define LIMIT_NETDEBUG(fmt, args...) \
2145 do { if (net_msg_warn && net_ratelimit()) printk(fmt,##args); } while(0)
2147 extern __u32 sysctl_wmem_max
;
2148 extern __u32 sysctl_rmem_max
;
2150 extern void sk_init(void);
2152 extern int sysctl_optmem_max
;
2154 extern __u32 sysctl_wmem_default
;
2155 extern __u32 sysctl_rmem_default
;
2157 #endif /* _SOCK_H */