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/bitops.h>
50 #include <linux/lockdep.h>
51 #include <linux/netdevice.h>
52 #include <linux/skbuff.h> /* struct sk_buff */
54 #include <linux/security.h>
55 #include <linux/slab.h>
56 #include <linux/uaccess.h>
57 #include <linux/memcontrol.h>
58 #include <linux/res_counter.h>
59 #include <linux/static_key.h>
60 #include <linux/aio.h>
61 #include <linux/sched.h>
63 #include <linux/filter.h>
64 #include <linux/rculist_nulls.h>
65 #include <linux/poll.h>
67 #include <linux/atomic.h>
69 #include <net/checksum.h>
74 int mem_cgroup_sockets_init(struct mem_cgroup
*memcg
, struct cgroup_subsys
*ss
);
75 void mem_cgroup_sockets_destroy(struct mem_cgroup
*memcg
);
78 int mem_cgroup_sockets_init(struct mem_cgroup
*memcg
, struct cgroup_subsys
*ss
)
83 void mem_cgroup_sockets_destroy(struct mem_cgroup
*memcg
)
88 * This structure really needs to be cleaned up.
89 * Most of it is for TCP, and not used by any of
90 * the other protocols.
93 /* Define this to get the SOCK_DBG debugging facility. */
94 #define SOCK_DEBUGGING
96 #define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \
97 printk(KERN_DEBUG msg); } while (0)
99 /* Validate arguments and do nothing */
100 static inline __printf(2, 3)
101 void SOCK_DEBUG(const struct sock
*sk
, const char *msg
, ...)
106 /* This is the per-socket lock. The spinlock provides a synchronization
107 * between user contexts and software interrupt processing, whereas the
108 * mini-semaphore synchronizes multiple users amongst themselves.
113 wait_queue_head_t wq
;
115 * We express the mutex-alike socket_lock semantics
116 * to the lock validator by explicitly managing
117 * the slock as a lock variant (in addition to
120 #ifdef CONFIG_DEBUG_LOCK_ALLOC
121 struct lockdep_map dep_map
;
130 * struct sock_common - minimal network layer representation of sockets
131 * @skc_daddr: Foreign IPv4 addr
132 * @skc_rcv_saddr: Bound local IPv4 addr
133 * @skc_hash: hash value used with various protocol lookup tables
134 * @skc_u16hashes: two u16 hash values used by UDP lookup tables
135 * @skc_family: network address family
136 * @skc_state: Connection state
137 * @skc_reuse: %SO_REUSEADDR setting
138 * @skc_bound_dev_if: bound device index if != 0
139 * @skc_bind_node: bind hash linkage for various protocol lookup tables
140 * @skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol
141 * @skc_prot: protocol handlers inside a network family
142 * @skc_net: reference to the network namespace of this socket
143 * @skc_node: main hash linkage for various protocol lookup tables
144 * @skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol
145 * @skc_tx_queue_mapping: tx queue number for this connection
146 * @skc_refcnt: reference count
148 * This is the minimal network layer representation of sockets, the header
149 * for struct sock and struct inet_timewait_sock.
152 /* skc_daddr and skc_rcv_saddr must be grouped :
153 * cf INET_MATCH() and INET_TW_MATCH()
156 __be32 skc_rcv_saddr
;
159 unsigned int skc_hash
;
160 __u16 skc_u16hashes
[2];
162 unsigned short skc_family
;
163 volatile unsigned char skc_state
;
164 unsigned char skc_reuse
;
165 int skc_bound_dev_if
;
167 struct hlist_node skc_bind_node
;
168 struct hlist_nulls_node skc_portaddr_node
;
170 struct proto
*skc_prot
;
175 * fields between dontcopy_begin/dontcopy_end
176 * are not copied in sock_copy()
179 int skc_dontcopy_begin
[0];
182 struct hlist_node skc_node
;
183 struct hlist_nulls_node skc_nulls_node
;
185 int skc_tx_queue_mapping
;
188 int skc_dontcopy_end
[0];
194 * struct sock - network layer representation of sockets
195 * @__sk_common: shared layout with inet_timewait_sock
196 * @sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
197 * @sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
198 * @sk_lock: synchronizer
199 * @sk_rcvbuf: size of receive buffer in bytes
200 * @sk_wq: sock wait queue and async head
201 * @sk_dst_cache: destination cache
202 * @sk_dst_lock: destination cache lock
203 * @sk_policy: flow policy
204 * @sk_receive_queue: incoming packets
205 * @sk_wmem_alloc: transmit queue bytes committed
206 * @sk_write_queue: Packet sending queue
207 * @sk_async_wait_queue: DMA copied packets
208 * @sk_omem_alloc: "o" is "option" or "other"
209 * @sk_wmem_queued: persistent queue size
210 * @sk_forward_alloc: space allocated forward
211 * @sk_allocation: allocation mode
212 * @sk_sndbuf: size of send buffer in bytes
213 * @sk_flags: %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE,
214 * %SO_OOBINLINE settings, %SO_TIMESTAMPING settings
215 * @sk_no_check: %SO_NO_CHECK setting, wether or not checkup packets
216 * @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
217 * @sk_route_nocaps: forbidden route capabilities (e.g NETIF_F_GSO_MASK)
218 * @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
219 * @sk_gso_max_size: Maximum GSO segment size to build
220 * @sk_lingertime: %SO_LINGER l_linger setting
221 * @sk_backlog: always used with the per-socket spinlock held
222 * @sk_callback_lock: used with the callbacks in the end of this struct
223 * @sk_error_queue: rarely used
224 * @sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt,
225 * IPV6_ADDRFORM for instance)
226 * @sk_err: last error
227 * @sk_err_soft: errors that don't cause failure but are the cause of a
228 * persistent failure not just 'timed out'
229 * @sk_drops: raw/udp drops counter
230 * @sk_ack_backlog: current listen backlog
231 * @sk_max_ack_backlog: listen backlog set in listen()
232 * @sk_priority: %SO_PRIORITY setting
233 * @sk_cgrp_prioidx: socket group's priority map index
234 * @sk_type: socket type (%SOCK_STREAM, etc)
235 * @sk_protocol: which protocol this socket belongs in this network family
236 * @sk_peer_pid: &struct pid for this socket's peer
237 * @sk_peer_cred: %SO_PEERCRED setting
238 * @sk_rcvlowat: %SO_RCVLOWAT setting
239 * @sk_rcvtimeo: %SO_RCVTIMEO setting
240 * @sk_sndtimeo: %SO_SNDTIMEO setting
241 * @sk_rxhash: flow hash received from netif layer
242 * @sk_filter: socket filtering instructions
243 * @sk_protinfo: private area, net family specific, when not using slab
244 * @sk_timer: sock cleanup timer
245 * @sk_stamp: time stamp of last packet received
246 * @sk_socket: Identd and reporting IO signals
247 * @sk_user_data: RPC layer private data
248 * @sk_sndmsg_page: cached page for sendmsg
249 * @sk_sndmsg_off: cached offset for sendmsg
250 * @sk_peek_off: current peek_offset value
251 * @sk_send_head: front of stuff to transmit
252 * @sk_security: used by security modules
253 * @sk_mark: generic packet mark
254 * @sk_classid: this socket's cgroup classid
255 * @sk_cgrp: this socket's cgroup-specific proto data
256 * @sk_write_pending: a write to stream socket waits to start
257 * @sk_state_change: callback to indicate change in the state of the sock
258 * @sk_data_ready: callback to indicate there is data to be processed
259 * @sk_write_space: callback to indicate there is bf sending space available
260 * @sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
261 * @sk_backlog_rcv: callback to process the backlog
262 * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
266 * Now struct inet_timewait_sock also uses sock_common, so please just
267 * don't add nothing before this first member (__sk_common) --acme
269 struct sock_common __sk_common
;
270 #define sk_node __sk_common.skc_node
271 #define sk_nulls_node __sk_common.skc_nulls_node
272 #define sk_refcnt __sk_common.skc_refcnt
273 #define sk_tx_queue_mapping __sk_common.skc_tx_queue_mapping
275 #define sk_dontcopy_begin __sk_common.skc_dontcopy_begin
276 #define sk_dontcopy_end __sk_common.skc_dontcopy_end
277 #define sk_hash __sk_common.skc_hash
278 #define sk_family __sk_common.skc_family
279 #define sk_state __sk_common.skc_state
280 #define sk_reuse __sk_common.skc_reuse
281 #define sk_bound_dev_if __sk_common.skc_bound_dev_if
282 #define sk_bind_node __sk_common.skc_bind_node
283 #define sk_prot __sk_common.skc_prot
284 #define sk_net __sk_common.skc_net
285 socket_lock_t sk_lock
;
286 struct sk_buff_head sk_receive_queue
;
288 * The backlog queue is special, it is always used with
289 * the per-socket spinlock held and requires low latency
290 * access. Therefore we special case it's implementation.
291 * Note : rmem_alloc is in this structure to fill a hole
292 * on 64bit arches, not because its logically part of
298 struct sk_buff
*head
;
299 struct sk_buff
*tail
;
301 #define sk_rmem_alloc sk_backlog.rmem_alloc
302 int sk_forward_alloc
;
309 struct sk_filter __rcu
*sk_filter
;
310 struct socket_wq __rcu
*sk_wq
;
312 #ifdef CONFIG_NET_DMA
313 struct sk_buff_head sk_async_wait_queue
;
317 struct xfrm_policy
*sk_policy
[2];
319 unsigned long sk_flags
;
320 struct dst_entry
*sk_dst_cache
;
321 spinlock_t sk_dst_lock
;
322 atomic_t sk_wmem_alloc
;
323 atomic_t sk_omem_alloc
;
325 struct sk_buff_head sk_write_queue
;
326 kmemcheck_bitfield_begin(flags
);
327 unsigned int sk_shutdown
: 2,
332 kmemcheck_bitfield_end(flags
);
335 netdev_features_t sk_route_caps
;
336 netdev_features_t sk_route_nocaps
;
338 unsigned int sk_gso_max_size
;
340 unsigned long sk_lingertime
;
341 struct sk_buff_head sk_error_queue
;
342 struct proto
*sk_prot_creator
;
343 rwlock_t sk_callback_lock
;
346 unsigned short sk_ack_backlog
;
347 unsigned short sk_max_ack_backlog
;
349 #ifdef CONFIG_CGROUPS
350 __u32 sk_cgrp_prioidx
;
352 struct pid
*sk_peer_pid
;
353 const struct cred
*sk_peer_cred
;
357 struct timer_list sk_timer
;
359 struct socket
*sk_socket
;
361 struct page
*sk_sndmsg_page
;
362 struct sk_buff
*sk_send_head
;
365 int sk_write_pending
;
366 #ifdef CONFIG_SECURITY
371 struct cg_proto
*sk_cgrp
;
372 void (*sk_state_change
)(struct sock
*sk
);
373 void (*sk_data_ready
)(struct sock
*sk
, int bytes
);
374 void (*sk_write_space
)(struct sock
*sk
);
375 void (*sk_error_report
)(struct sock
*sk
);
376 int (*sk_backlog_rcv
)(struct sock
*sk
,
377 struct sk_buff
*skb
);
378 void (*sk_destruct
)(struct sock
*sk
);
382 * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK
383 * or not whether his port will be reused by someone else. SK_FORCE_REUSE
384 * on a socket means that the socket will reuse everybody else's port
385 * without looking at the other's sk_reuse value.
388 #define SK_NO_REUSE 0
389 #define SK_CAN_REUSE 1
390 #define SK_FORCE_REUSE 2
392 static inline int sk_peek_offset(struct sock
*sk
, int flags
)
394 if ((flags
& MSG_PEEK
) && (sk
->sk_peek_off
>= 0))
395 return sk
->sk_peek_off
;
400 static inline void sk_peek_offset_bwd(struct sock
*sk
, int val
)
402 if (sk
->sk_peek_off
>= 0) {
403 if (sk
->sk_peek_off
>= val
)
404 sk
->sk_peek_off
-= val
;
410 static inline void sk_peek_offset_fwd(struct sock
*sk
, int val
)
412 if (sk
->sk_peek_off
>= 0)
413 sk
->sk_peek_off
+= val
;
417 * Hashed lists helper routines
419 static inline struct sock
*sk_entry(const struct hlist_node
*node
)
421 return hlist_entry(node
, struct sock
, sk_node
);
424 static inline struct sock
*__sk_head(const struct hlist_head
*head
)
426 return hlist_entry(head
->first
, struct sock
, sk_node
);
429 static inline struct sock
*sk_head(const struct hlist_head
*head
)
431 return hlist_empty(head
) ? NULL
: __sk_head(head
);
434 static inline struct sock
*__sk_nulls_head(const struct hlist_nulls_head
*head
)
436 return hlist_nulls_entry(head
->first
, struct sock
, sk_nulls_node
);
439 static inline struct sock
*sk_nulls_head(const struct hlist_nulls_head
*head
)
441 return hlist_nulls_empty(head
) ? NULL
: __sk_nulls_head(head
);
444 static inline struct sock
*sk_next(const struct sock
*sk
)
446 return sk
->sk_node
.next
?
447 hlist_entry(sk
->sk_node
.next
, struct sock
, sk_node
) : NULL
;
450 static inline struct sock
*sk_nulls_next(const struct sock
*sk
)
452 return (!is_a_nulls(sk
->sk_nulls_node
.next
)) ?
453 hlist_nulls_entry(sk
->sk_nulls_node
.next
,
454 struct sock
, sk_nulls_node
) :
458 static inline bool sk_unhashed(const struct sock
*sk
)
460 return hlist_unhashed(&sk
->sk_node
);
463 static inline bool sk_hashed(const struct sock
*sk
)
465 return !sk_unhashed(sk
);
468 static inline void sk_node_init(struct hlist_node
*node
)
473 static inline void sk_nulls_node_init(struct hlist_nulls_node
*node
)
478 static inline void __sk_del_node(struct sock
*sk
)
480 __hlist_del(&sk
->sk_node
);
483 /* NB: equivalent to hlist_del_init_rcu */
484 static inline bool __sk_del_node_init(struct sock
*sk
)
488 sk_node_init(&sk
->sk_node
);
494 /* Grab socket reference count. This operation is valid only
495 when sk is ALREADY grabbed f.e. it is found in hash table
496 or a list and the lookup is made under lock preventing hash table
500 static inline void sock_hold(struct sock
*sk
)
502 atomic_inc(&sk
->sk_refcnt
);
505 /* Ungrab socket in the context, which assumes that socket refcnt
506 cannot hit zero, f.e. it is true in context of any socketcall.
508 static inline void __sock_put(struct sock
*sk
)
510 atomic_dec(&sk
->sk_refcnt
);
513 static inline bool sk_del_node_init(struct sock
*sk
)
515 bool rc
= __sk_del_node_init(sk
);
518 /* paranoid for a while -acme */
519 WARN_ON(atomic_read(&sk
->sk_refcnt
) == 1);
524 #define sk_del_node_init_rcu(sk) sk_del_node_init(sk)
526 static inline bool __sk_nulls_del_node_init_rcu(struct sock
*sk
)
529 hlist_nulls_del_init_rcu(&sk
->sk_nulls_node
);
535 static inline bool sk_nulls_del_node_init_rcu(struct sock
*sk
)
537 bool rc
= __sk_nulls_del_node_init_rcu(sk
);
540 /* paranoid for a while -acme */
541 WARN_ON(atomic_read(&sk
->sk_refcnt
) == 1);
547 static inline void __sk_add_node(struct sock
*sk
, struct hlist_head
*list
)
549 hlist_add_head(&sk
->sk_node
, list
);
552 static inline void sk_add_node(struct sock
*sk
, struct hlist_head
*list
)
555 __sk_add_node(sk
, list
);
558 static inline void sk_add_node_rcu(struct sock
*sk
, struct hlist_head
*list
)
561 hlist_add_head_rcu(&sk
->sk_node
, list
);
564 static inline void __sk_nulls_add_node_rcu(struct sock
*sk
, struct hlist_nulls_head
*list
)
566 hlist_nulls_add_head_rcu(&sk
->sk_nulls_node
, list
);
569 static inline void sk_nulls_add_node_rcu(struct sock
*sk
, struct hlist_nulls_head
*list
)
572 __sk_nulls_add_node_rcu(sk
, list
);
575 static inline void __sk_del_bind_node(struct sock
*sk
)
577 __hlist_del(&sk
->sk_bind_node
);
580 static inline void sk_add_bind_node(struct sock
*sk
,
581 struct hlist_head
*list
)
583 hlist_add_head(&sk
->sk_bind_node
, list
);
586 #define sk_for_each(__sk, node, list) \
587 hlist_for_each_entry(__sk, node, list, sk_node)
588 #define sk_for_each_rcu(__sk, node, list) \
589 hlist_for_each_entry_rcu(__sk, node, list, sk_node)
590 #define sk_nulls_for_each(__sk, node, list) \
591 hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)
592 #define sk_nulls_for_each_rcu(__sk, node, list) \
593 hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)
594 #define sk_for_each_from(__sk, node) \
595 if (__sk && ({ node = &(__sk)->sk_node; 1; })) \
596 hlist_for_each_entry_from(__sk, node, sk_node)
597 #define sk_nulls_for_each_from(__sk, node) \
598 if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \
599 hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node)
600 #define sk_for_each_safe(__sk, node, tmp, list) \
601 hlist_for_each_entry_safe(__sk, node, tmp, list, sk_node)
602 #define sk_for_each_bound(__sk, node, list) \
603 hlist_for_each_entry(__sk, node, list, sk_bind_node)
616 SOCK_USE_WRITE_QUEUE
, /* whether to call sk->sk_write_space in sock_wfree */
617 SOCK_DBG
, /* %SO_DEBUG setting */
618 SOCK_RCVTSTAMP
, /* %SO_TIMESTAMP setting */
619 SOCK_RCVTSTAMPNS
, /* %SO_TIMESTAMPNS setting */
620 SOCK_LOCALROUTE
, /* route locally only, %SO_DONTROUTE setting */
621 SOCK_QUEUE_SHRUNK
, /* write queue has been shrunk recently */
622 SOCK_TIMESTAMPING_TX_HARDWARE
, /* %SOF_TIMESTAMPING_TX_HARDWARE */
623 SOCK_TIMESTAMPING_TX_SOFTWARE
, /* %SOF_TIMESTAMPING_TX_SOFTWARE */
624 SOCK_TIMESTAMPING_RX_HARDWARE
, /* %SOF_TIMESTAMPING_RX_HARDWARE */
625 SOCK_TIMESTAMPING_RX_SOFTWARE
, /* %SOF_TIMESTAMPING_RX_SOFTWARE */
626 SOCK_TIMESTAMPING_SOFTWARE
, /* %SOF_TIMESTAMPING_SOFTWARE */
627 SOCK_TIMESTAMPING_RAW_HARDWARE
, /* %SOF_TIMESTAMPING_RAW_HARDWARE */
628 SOCK_TIMESTAMPING_SYS_HARDWARE
, /* %SOF_TIMESTAMPING_SYS_HARDWARE */
629 SOCK_FASYNC
, /* fasync() active */
631 SOCK_ZEROCOPY
, /* buffers from userspace */
632 SOCK_WIFI_STATUS
, /* push wifi status to userspace */
633 SOCK_NOFCS
, /* Tell NIC not to do the Ethernet FCS.
634 * Will use last 4 bytes of packet sent from
635 * user-space instead.
639 static inline void sock_copy_flags(struct sock
*nsk
, struct sock
*osk
)
641 nsk
->sk_flags
= osk
->sk_flags
;
644 static inline void sock_set_flag(struct sock
*sk
, enum sock_flags flag
)
646 __set_bit(flag
, &sk
->sk_flags
);
649 static inline void sock_reset_flag(struct sock
*sk
, enum sock_flags flag
)
651 __clear_bit(flag
, &sk
->sk_flags
);
654 static inline bool sock_flag(const struct sock
*sk
, enum sock_flags flag
)
656 return test_bit(flag
, &sk
->sk_flags
);
659 static inline void sk_acceptq_removed(struct sock
*sk
)
661 sk
->sk_ack_backlog
--;
664 static inline void sk_acceptq_added(struct sock
*sk
)
666 sk
->sk_ack_backlog
++;
669 static inline bool sk_acceptq_is_full(const struct sock
*sk
)
671 return sk
->sk_ack_backlog
> sk
->sk_max_ack_backlog
;
675 * Compute minimal free write space needed to queue new packets.
677 static inline int sk_stream_min_wspace(const struct sock
*sk
)
679 return sk
->sk_wmem_queued
>> 1;
682 static inline int sk_stream_wspace(const struct sock
*sk
)
684 return sk
->sk_sndbuf
- sk
->sk_wmem_queued
;
687 extern void sk_stream_write_space(struct sock
*sk
);
689 static inline bool sk_stream_memory_free(const struct sock
*sk
)
691 return sk
->sk_wmem_queued
< sk
->sk_sndbuf
;
694 /* OOB backlog add */
695 static inline void __sk_add_backlog(struct sock
*sk
, struct sk_buff
*skb
)
697 /* dont let skb dst not refcounted, we are going to leave rcu lock */
700 if (!sk
->sk_backlog
.tail
)
701 sk
->sk_backlog
.head
= skb
;
703 sk
->sk_backlog
.tail
->next
= skb
;
705 sk
->sk_backlog
.tail
= skb
;
710 * Take into account size of receive queue and backlog queue
711 * Do not take into account this skb truesize,
712 * to allow even a single big packet to come.
714 static inline bool sk_rcvqueues_full(const struct sock
*sk
, const struct sk_buff
*skb
,
717 unsigned int qsize
= sk
->sk_backlog
.len
+ atomic_read(&sk
->sk_rmem_alloc
);
719 return qsize
> limit
;
722 /* The per-socket spinlock must be held here. */
723 static inline __must_check
int sk_add_backlog(struct sock
*sk
, struct sk_buff
*skb
,
726 if (sk_rcvqueues_full(sk
, skb
, limit
))
729 __sk_add_backlog(sk
, skb
);
730 sk
->sk_backlog
.len
+= skb
->truesize
;
734 static inline int sk_backlog_rcv(struct sock
*sk
, struct sk_buff
*skb
)
736 return sk
->sk_backlog_rcv(sk
, skb
);
739 static inline void sock_rps_record_flow(const struct sock
*sk
)
742 struct rps_sock_flow_table
*sock_flow_table
;
745 sock_flow_table
= rcu_dereference(rps_sock_flow_table
);
746 rps_record_sock_flow(sock_flow_table
, sk
->sk_rxhash
);
751 static inline void sock_rps_reset_flow(const struct sock
*sk
)
754 struct rps_sock_flow_table
*sock_flow_table
;
757 sock_flow_table
= rcu_dereference(rps_sock_flow_table
);
758 rps_reset_sock_flow(sock_flow_table
, sk
->sk_rxhash
);
763 static inline void sock_rps_save_rxhash(struct sock
*sk
,
764 const struct sk_buff
*skb
)
767 if (unlikely(sk
->sk_rxhash
!= skb
->rxhash
)) {
768 sock_rps_reset_flow(sk
);
769 sk
->sk_rxhash
= skb
->rxhash
;
774 static inline void sock_rps_reset_rxhash(struct sock
*sk
)
777 sock_rps_reset_flow(sk
);
782 #define sk_wait_event(__sk, __timeo, __condition) \
784 release_sock(__sk); \
785 __rc = __condition; \
787 *(__timeo) = schedule_timeout(*(__timeo)); \
790 __rc = __condition; \
794 extern int sk_stream_wait_connect(struct sock
*sk
, long *timeo_p
);
795 extern int sk_stream_wait_memory(struct sock
*sk
, long *timeo_p
);
796 extern void sk_stream_wait_close(struct sock
*sk
, long timeo_p
);
797 extern int sk_stream_error(struct sock
*sk
, int flags
, int err
);
798 extern void sk_stream_kill_queues(struct sock
*sk
);
800 extern int sk_wait_data(struct sock
*sk
, long *timeo
);
802 struct request_sock_ops
;
803 struct timewait_sock_ops
;
804 struct inet_hashinfo
;
808 /* Networking protocol blocks we attach to sockets.
809 * socket layer -> transport layer interface
810 * transport -> network interface is defined by struct inet_proto
813 void (*close
)(struct sock
*sk
,
815 int (*connect
)(struct sock
*sk
,
816 struct sockaddr
*uaddr
,
818 int (*disconnect
)(struct sock
*sk
, int flags
);
820 struct sock
* (*accept
)(struct sock
*sk
, int flags
, int *err
);
822 int (*ioctl
)(struct sock
*sk
, int cmd
,
824 int (*init
)(struct sock
*sk
);
825 void (*destroy
)(struct sock
*sk
);
826 void (*shutdown
)(struct sock
*sk
, int how
);
827 int (*setsockopt
)(struct sock
*sk
, int level
,
828 int optname
, char __user
*optval
,
829 unsigned int optlen
);
830 int (*getsockopt
)(struct sock
*sk
, int level
,
831 int optname
, char __user
*optval
,
834 int (*compat_setsockopt
)(struct sock
*sk
,
836 int optname
, char __user
*optval
,
837 unsigned int optlen
);
838 int (*compat_getsockopt
)(struct sock
*sk
,
840 int optname
, char __user
*optval
,
842 int (*compat_ioctl
)(struct sock
*sk
,
843 unsigned int cmd
, unsigned long arg
);
845 int (*sendmsg
)(struct kiocb
*iocb
, struct sock
*sk
,
846 struct msghdr
*msg
, size_t len
);
847 int (*recvmsg
)(struct kiocb
*iocb
, struct sock
*sk
,
849 size_t len
, int noblock
, int flags
,
851 int (*sendpage
)(struct sock
*sk
, struct page
*page
,
852 int offset
, size_t size
, int flags
);
853 int (*bind
)(struct sock
*sk
,
854 struct sockaddr
*uaddr
, int addr_len
);
856 int (*backlog_rcv
) (struct sock
*sk
,
857 struct sk_buff
*skb
);
859 /* Keeping track of sk's, looking them up, and port selection methods. */
860 void (*hash
)(struct sock
*sk
);
861 void (*unhash
)(struct sock
*sk
);
862 void (*rehash
)(struct sock
*sk
);
863 int (*get_port
)(struct sock
*sk
, unsigned short snum
);
864 void (*clear_sk
)(struct sock
*sk
, int size
);
866 /* Keeping track of sockets in use */
867 #ifdef CONFIG_PROC_FS
868 unsigned int inuse_idx
;
871 /* Memory pressure */
872 void (*enter_memory_pressure
)(struct sock
*sk
);
873 atomic_long_t
*memory_allocated
; /* Current allocated memory. */
874 struct percpu_counter
*sockets_allocated
; /* Current number of sockets. */
876 * Pressure flag: try to collapse.
877 * Technical note: it is used by multiple contexts non atomically.
878 * All the __sk_mem_schedule() is of this nature: accounting
879 * is strict, actions are advisory and have some latency.
881 int *memory_pressure
;
888 struct kmem_cache
*slab
;
889 unsigned int obj_size
;
892 struct percpu_counter
*orphan_count
;
894 struct request_sock_ops
*rsk_prot
;
895 struct timewait_sock_ops
*twsk_prot
;
898 struct inet_hashinfo
*hashinfo
;
899 struct udp_table
*udp_table
;
900 struct raw_hashinfo
*raw_hash
;
903 struct module
*owner
;
907 struct list_head node
;
908 #ifdef SOCK_REFCNT_DEBUG
911 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_KMEM
913 * cgroup specific init/deinit functions. Called once for all
914 * protocols that implement it, from cgroups populate function.
915 * This function has to setup any files the protocol want to
916 * appear in the kmem cgroup filesystem.
918 int (*init_cgroup
)(struct mem_cgroup
*memcg
,
919 struct cgroup_subsys
*ss
);
920 void (*destroy_cgroup
)(struct mem_cgroup
*memcg
);
921 struct cg_proto
*(*proto_cgroup
)(struct mem_cgroup
*memcg
);
926 * Bits in struct cg_proto.flags
928 enum cg_proto_flags
{
929 /* Currently active and new sockets should be assigned to cgroups */
931 /* It was ever activated; we must disarm static keys on destruction */
932 MEMCG_SOCK_ACTIVATED
,
936 void (*enter_memory_pressure
)(struct sock
*sk
);
937 struct res_counter
*memory_allocated
; /* Current allocated memory. */
938 struct percpu_counter
*sockets_allocated
; /* Current number of sockets. */
939 int *memory_pressure
;
943 * memcg field is used to find which memcg we belong directly
944 * Each memcg struct can hold more than one cg_proto, so container_of
947 * The elegant solution would be having an inverse function to
948 * proto_cgroup in struct proto, but that means polluting the structure
949 * for everybody, instead of just for memcg users.
951 struct mem_cgroup
*memcg
;
954 extern int proto_register(struct proto
*prot
, int alloc_slab
);
955 extern void proto_unregister(struct proto
*prot
);
957 static inline bool memcg_proto_active(struct cg_proto
*cg_proto
)
959 return test_bit(MEMCG_SOCK_ACTIVE
, &cg_proto
->flags
);
962 static inline bool memcg_proto_activated(struct cg_proto
*cg_proto
)
964 return test_bit(MEMCG_SOCK_ACTIVATED
, &cg_proto
->flags
);
967 #ifdef SOCK_REFCNT_DEBUG
968 static inline void sk_refcnt_debug_inc(struct sock
*sk
)
970 atomic_inc(&sk
->sk_prot
->socks
);
973 static inline void sk_refcnt_debug_dec(struct sock
*sk
)
975 atomic_dec(&sk
->sk_prot
->socks
);
976 printk(KERN_DEBUG
"%s socket %p released, %d are still alive\n",
977 sk
->sk_prot
->name
, sk
, atomic_read(&sk
->sk_prot
->socks
));
980 inline void sk_refcnt_debug_release(const struct sock
*sk
)
982 if (atomic_read(&sk
->sk_refcnt
) != 1)
983 printk(KERN_DEBUG
"Destruction of the %s socket %p delayed, refcnt=%d\n",
984 sk
->sk_prot
->name
, sk
, atomic_read(&sk
->sk_refcnt
));
986 #else /* SOCK_REFCNT_DEBUG */
987 #define sk_refcnt_debug_inc(sk) do { } while (0)
988 #define sk_refcnt_debug_dec(sk) do { } while (0)
989 #define sk_refcnt_debug_release(sk) do { } while (0)
990 #endif /* SOCK_REFCNT_DEBUG */
992 #if defined(CONFIG_CGROUP_MEM_RES_CTLR_KMEM) && defined(CONFIG_NET)
993 extern struct static_key memcg_socket_limit_enabled
;
994 static inline struct cg_proto
*parent_cg_proto(struct proto
*proto
,
995 struct cg_proto
*cg_proto
)
997 return proto
->proto_cgroup(parent_mem_cgroup(cg_proto
->memcg
));
999 #define mem_cgroup_sockets_enabled static_key_false(&memcg_socket_limit_enabled)
1001 #define mem_cgroup_sockets_enabled 0
1002 static inline struct cg_proto
*parent_cg_proto(struct proto
*proto
,
1003 struct cg_proto
*cg_proto
)
1010 static inline bool sk_has_memory_pressure(const struct sock
*sk
)
1012 return sk
->sk_prot
->memory_pressure
!= NULL
;
1015 static inline bool sk_under_memory_pressure(const struct sock
*sk
)
1017 if (!sk
->sk_prot
->memory_pressure
)
1020 if (mem_cgroup_sockets_enabled
&& sk
->sk_cgrp
)
1021 return !!*sk
->sk_cgrp
->memory_pressure
;
1023 return !!*sk
->sk_prot
->memory_pressure
;
1026 static inline void sk_leave_memory_pressure(struct sock
*sk
)
1028 int *memory_pressure
= sk
->sk_prot
->memory_pressure
;
1030 if (!memory_pressure
)
1033 if (*memory_pressure
)
1034 *memory_pressure
= 0;
1036 if (mem_cgroup_sockets_enabled
&& sk
->sk_cgrp
) {
1037 struct cg_proto
*cg_proto
= sk
->sk_cgrp
;
1038 struct proto
*prot
= sk
->sk_prot
;
1040 for (; cg_proto
; cg_proto
= parent_cg_proto(prot
, cg_proto
))
1041 if (*cg_proto
->memory_pressure
)
1042 *cg_proto
->memory_pressure
= 0;
1047 static inline void sk_enter_memory_pressure(struct sock
*sk
)
1049 if (!sk
->sk_prot
->enter_memory_pressure
)
1052 if (mem_cgroup_sockets_enabled
&& sk
->sk_cgrp
) {
1053 struct cg_proto
*cg_proto
= sk
->sk_cgrp
;
1054 struct proto
*prot
= sk
->sk_prot
;
1056 for (; cg_proto
; cg_proto
= parent_cg_proto(prot
, cg_proto
))
1057 cg_proto
->enter_memory_pressure(sk
);
1060 sk
->sk_prot
->enter_memory_pressure(sk
);
1063 static inline long sk_prot_mem_limits(const struct sock
*sk
, int index
)
1065 long *prot
= sk
->sk_prot
->sysctl_mem
;
1066 if (mem_cgroup_sockets_enabled
&& sk
->sk_cgrp
)
1067 prot
= sk
->sk_cgrp
->sysctl_mem
;
1071 static inline void memcg_memory_allocated_add(struct cg_proto
*prot
,
1075 struct res_counter
*fail
;
1078 ret
= res_counter_charge_nofail(prot
->memory_allocated
,
1079 amt
<< PAGE_SHIFT
, &fail
);
1081 *parent_status
= OVER_LIMIT
;
1084 static inline void memcg_memory_allocated_sub(struct cg_proto
*prot
,
1087 res_counter_uncharge(prot
->memory_allocated
, amt
<< PAGE_SHIFT
);
1090 static inline u64
memcg_memory_allocated_read(struct cg_proto
*prot
)
1093 ret
= res_counter_read_u64(prot
->memory_allocated
, RES_USAGE
);
1094 return ret
>> PAGE_SHIFT
;
1098 sk_memory_allocated(const struct sock
*sk
)
1100 struct proto
*prot
= sk
->sk_prot
;
1101 if (mem_cgroup_sockets_enabled
&& sk
->sk_cgrp
)
1102 return memcg_memory_allocated_read(sk
->sk_cgrp
);
1104 return atomic_long_read(prot
->memory_allocated
);
1108 sk_memory_allocated_add(struct sock
*sk
, int amt
, int *parent_status
)
1110 struct proto
*prot
= sk
->sk_prot
;
1112 if (mem_cgroup_sockets_enabled
&& sk
->sk_cgrp
) {
1113 memcg_memory_allocated_add(sk
->sk_cgrp
, amt
, parent_status
);
1114 /* update the root cgroup regardless */
1115 atomic_long_add_return(amt
, prot
->memory_allocated
);
1116 return memcg_memory_allocated_read(sk
->sk_cgrp
);
1119 return atomic_long_add_return(amt
, prot
->memory_allocated
);
1123 sk_memory_allocated_sub(struct sock
*sk
, int amt
)
1125 struct proto
*prot
= sk
->sk_prot
;
1127 if (mem_cgroup_sockets_enabled
&& sk
->sk_cgrp
)
1128 memcg_memory_allocated_sub(sk
->sk_cgrp
, amt
);
1130 atomic_long_sub(amt
, prot
->memory_allocated
);
1133 static inline void sk_sockets_allocated_dec(struct sock
*sk
)
1135 struct proto
*prot
= sk
->sk_prot
;
1137 if (mem_cgroup_sockets_enabled
&& sk
->sk_cgrp
) {
1138 struct cg_proto
*cg_proto
= sk
->sk_cgrp
;
1140 for (; cg_proto
; cg_proto
= parent_cg_proto(prot
, cg_proto
))
1141 percpu_counter_dec(cg_proto
->sockets_allocated
);
1144 percpu_counter_dec(prot
->sockets_allocated
);
1147 static inline void sk_sockets_allocated_inc(struct sock
*sk
)
1149 struct proto
*prot
= sk
->sk_prot
;
1151 if (mem_cgroup_sockets_enabled
&& sk
->sk_cgrp
) {
1152 struct cg_proto
*cg_proto
= sk
->sk_cgrp
;
1154 for (; cg_proto
; cg_proto
= parent_cg_proto(prot
, cg_proto
))
1155 percpu_counter_inc(cg_proto
->sockets_allocated
);
1158 percpu_counter_inc(prot
->sockets_allocated
);
1162 sk_sockets_allocated_read_positive(struct sock
*sk
)
1164 struct proto
*prot
= sk
->sk_prot
;
1166 if (mem_cgroup_sockets_enabled
&& sk
->sk_cgrp
)
1167 return percpu_counter_read_positive(sk
->sk_cgrp
->sockets_allocated
);
1169 return percpu_counter_read_positive(prot
->sockets_allocated
);
1173 proto_sockets_allocated_sum_positive(struct proto
*prot
)
1175 return percpu_counter_sum_positive(prot
->sockets_allocated
);
1179 proto_memory_allocated(struct proto
*prot
)
1181 return atomic_long_read(prot
->memory_allocated
);
1185 proto_memory_pressure(struct proto
*prot
)
1187 if (!prot
->memory_pressure
)
1189 return !!*prot
->memory_pressure
;
1193 #ifdef CONFIG_PROC_FS
1194 /* Called with local bh disabled */
1195 extern void sock_prot_inuse_add(struct net
*net
, struct proto
*prot
, int inc
);
1196 extern int sock_prot_inuse_get(struct net
*net
, struct proto
*proto
);
1198 static inline void sock_prot_inuse_add(struct net
*net
, struct proto
*prot
,
1205 /* With per-bucket locks this operation is not-atomic, so that
1206 * this version is not worse.
1208 static inline void __sk_prot_rehash(struct sock
*sk
)
1210 sk
->sk_prot
->unhash(sk
);
1211 sk
->sk_prot
->hash(sk
);
1214 void sk_prot_clear_portaddr_nulls(struct sock
*sk
, int size
);
1216 /* About 10 seconds */
1217 #define SOCK_DESTROY_TIME (10*HZ)
1219 /* Sockets 0-1023 can't be bound to unless you are superuser */
1220 #define PROT_SOCK 1024
1222 #define SHUTDOWN_MASK 3
1223 #define RCV_SHUTDOWN 1
1224 #define SEND_SHUTDOWN 2
1226 #define SOCK_SNDBUF_LOCK 1
1227 #define SOCK_RCVBUF_LOCK 2
1228 #define SOCK_BINDADDR_LOCK 4
1229 #define SOCK_BINDPORT_LOCK 8
1231 /* sock_iocb: used to kick off async processing of socket ios */
1233 struct list_head list
;
1237 struct socket
*sock
;
1239 struct scm_cookie
*scm
;
1240 struct msghdr
*msg
, async_msg
;
1241 struct kiocb
*kiocb
;
1244 static inline struct sock_iocb
*kiocb_to_siocb(struct kiocb
*iocb
)
1246 return (struct sock_iocb
*)iocb
->private;
1249 static inline struct kiocb
*siocb_to_kiocb(struct sock_iocb
*si
)
1254 struct socket_alloc
{
1255 struct socket socket
;
1256 struct inode vfs_inode
;
1259 static inline struct socket
*SOCKET_I(struct inode
*inode
)
1261 return &container_of(inode
, struct socket_alloc
, vfs_inode
)->socket
;
1264 static inline struct inode
*SOCK_INODE(struct socket
*socket
)
1266 return &container_of(socket
, struct socket_alloc
, socket
)->vfs_inode
;
1270 * Functions for memory accounting
1272 extern int __sk_mem_schedule(struct sock
*sk
, int size
, int kind
);
1273 extern void __sk_mem_reclaim(struct sock
*sk
);
1275 #define SK_MEM_QUANTUM ((int)PAGE_SIZE)
1276 #define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM)
1277 #define SK_MEM_SEND 0
1278 #define SK_MEM_RECV 1
1280 static inline int sk_mem_pages(int amt
)
1282 return (amt
+ SK_MEM_QUANTUM
- 1) >> SK_MEM_QUANTUM_SHIFT
;
1285 static inline bool sk_has_account(struct sock
*sk
)
1287 /* return true if protocol supports memory accounting */
1288 return !!sk
->sk_prot
->memory_allocated
;
1291 static inline bool sk_wmem_schedule(struct sock
*sk
, int size
)
1293 if (!sk_has_account(sk
))
1295 return size
<= sk
->sk_forward_alloc
||
1296 __sk_mem_schedule(sk
, size
, SK_MEM_SEND
);
1299 static inline bool sk_rmem_schedule(struct sock
*sk
, int size
)
1301 if (!sk_has_account(sk
))
1303 return size
<= sk
->sk_forward_alloc
||
1304 __sk_mem_schedule(sk
, size
, SK_MEM_RECV
);
1307 static inline void sk_mem_reclaim(struct sock
*sk
)
1309 if (!sk_has_account(sk
))
1311 if (sk
->sk_forward_alloc
>= SK_MEM_QUANTUM
)
1312 __sk_mem_reclaim(sk
);
1315 static inline void sk_mem_reclaim_partial(struct sock
*sk
)
1317 if (!sk_has_account(sk
))
1319 if (sk
->sk_forward_alloc
> SK_MEM_QUANTUM
)
1320 __sk_mem_reclaim(sk
);
1323 static inline void sk_mem_charge(struct sock
*sk
, int size
)
1325 if (!sk_has_account(sk
))
1327 sk
->sk_forward_alloc
-= size
;
1330 static inline void sk_mem_uncharge(struct sock
*sk
, int size
)
1332 if (!sk_has_account(sk
))
1334 sk
->sk_forward_alloc
+= size
;
1337 static inline void sk_wmem_free_skb(struct sock
*sk
, struct sk_buff
*skb
)
1339 sock_set_flag(sk
, SOCK_QUEUE_SHRUNK
);
1340 sk
->sk_wmem_queued
-= skb
->truesize
;
1341 sk_mem_uncharge(sk
, skb
->truesize
);
1345 /* Used by processes to "lock" a socket state, so that
1346 * interrupts and bottom half handlers won't change it
1347 * from under us. It essentially blocks any incoming
1348 * packets, so that we won't get any new data or any
1349 * packets that change the state of the socket.
1351 * While locked, BH processing will add new packets to
1352 * the backlog queue. This queue is processed by the
1353 * owner of the socket lock right before it is released.
1355 * Since ~2.3.5 it is also exclusive sleep lock serializing
1356 * accesses from user process context.
1358 #define sock_owned_by_user(sk) ((sk)->sk_lock.owned)
1361 * Macro so as to not evaluate some arguments when
1362 * lockdep is not enabled.
1364 * Mark both the sk_lock and the sk_lock.slock as a
1365 * per-address-family lock class.
1367 #define sock_lock_init_class_and_name(sk, sname, skey, name, key) \
1369 sk->sk_lock.owned = 0; \
1370 init_waitqueue_head(&sk->sk_lock.wq); \
1371 spin_lock_init(&(sk)->sk_lock.slock); \
1372 debug_check_no_locks_freed((void *)&(sk)->sk_lock, \
1373 sizeof((sk)->sk_lock)); \
1374 lockdep_set_class_and_name(&(sk)->sk_lock.slock, \
1376 lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \
1379 extern void lock_sock_nested(struct sock
*sk
, int subclass
);
1381 static inline void lock_sock(struct sock
*sk
)
1383 lock_sock_nested(sk
, 0);
1386 extern void release_sock(struct sock
*sk
);
1388 /* BH context may only use the following locking interface. */
1389 #define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock))
1390 #define bh_lock_sock_nested(__sk) \
1391 spin_lock_nested(&((__sk)->sk_lock.slock), \
1392 SINGLE_DEPTH_NESTING)
1393 #define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock))
1395 extern bool lock_sock_fast(struct sock
*sk
);
1397 * unlock_sock_fast - complement of lock_sock_fast
1401 * fast unlock socket for user context.
1402 * If slow mode is on, we call regular release_sock()
1404 static inline void unlock_sock_fast(struct sock
*sk
, bool slow
)
1409 spin_unlock_bh(&sk
->sk_lock
.slock
);
1413 extern struct sock
*sk_alloc(struct net
*net
, int family
,
1415 struct proto
*prot
);
1416 extern void sk_free(struct sock
*sk
);
1417 extern void sk_release_kernel(struct sock
*sk
);
1418 extern struct sock
*sk_clone_lock(const struct sock
*sk
,
1419 const gfp_t priority
);
1421 extern struct sk_buff
*sock_wmalloc(struct sock
*sk
,
1422 unsigned long size
, int force
,
1424 extern struct sk_buff
*sock_rmalloc(struct sock
*sk
,
1425 unsigned long size
, int force
,
1427 extern void sock_wfree(struct sk_buff
*skb
);
1428 extern void sock_rfree(struct sk_buff
*skb
);
1430 extern int sock_setsockopt(struct socket
*sock
, int level
,
1431 int op
, char __user
*optval
,
1432 unsigned int optlen
);
1434 extern int sock_getsockopt(struct socket
*sock
, int level
,
1435 int op
, char __user
*optval
,
1436 int __user
*optlen
);
1437 extern struct sk_buff
*sock_alloc_send_skb(struct sock
*sk
,
1441 extern struct sk_buff
*sock_alloc_send_pskb(struct sock
*sk
,
1442 unsigned long header_len
,
1443 unsigned long data_len
,
1446 extern void *sock_kmalloc(struct sock
*sk
, int size
,
1448 extern void sock_kfree_s(struct sock
*sk
, void *mem
, int size
);
1449 extern void sk_send_sigurg(struct sock
*sk
);
1451 #ifdef CONFIG_CGROUPS
1452 extern void sock_update_classid(struct sock
*sk
);
1454 static inline void sock_update_classid(struct sock
*sk
)
1460 * Functions to fill in entries in struct proto_ops when a protocol
1461 * does not implement a particular function.
1463 extern int sock_no_bind(struct socket
*,
1464 struct sockaddr
*, int);
1465 extern int sock_no_connect(struct socket
*,
1466 struct sockaddr
*, int, int);
1467 extern int sock_no_socketpair(struct socket
*,
1469 extern int sock_no_accept(struct socket
*,
1470 struct socket
*, int);
1471 extern int sock_no_getname(struct socket
*,
1472 struct sockaddr
*, int *, int);
1473 extern unsigned int sock_no_poll(struct file
*, struct socket
*,
1474 struct poll_table_struct
*);
1475 extern int sock_no_ioctl(struct socket
*, unsigned int,
1477 extern int sock_no_listen(struct socket
*, int);
1478 extern int sock_no_shutdown(struct socket
*, int);
1479 extern int sock_no_getsockopt(struct socket
*, int , int,
1480 char __user
*, int __user
*);
1481 extern int sock_no_setsockopt(struct socket
*, int, int,
1482 char __user
*, unsigned int);
1483 extern int sock_no_sendmsg(struct kiocb
*, struct socket
*,
1484 struct msghdr
*, size_t);
1485 extern int sock_no_recvmsg(struct kiocb
*, struct socket
*,
1486 struct msghdr
*, size_t, int);
1487 extern int sock_no_mmap(struct file
*file
,
1488 struct socket
*sock
,
1489 struct vm_area_struct
*vma
);
1490 extern ssize_t
sock_no_sendpage(struct socket
*sock
,
1492 int offset
, size_t size
,
1496 * Functions to fill in entries in struct proto_ops when a protocol
1497 * uses the inet style.
1499 extern int sock_common_getsockopt(struct socket
*sock
, int level
, int optname
,
1500 char __user
*optval
, int __user
*optlen
);
1501 extern int sock_common_recvmsg(struct kiocb
*iocb
, struct socket
*sock
,
1502 struct msghdr
*msg
, size_t size
, int flags
);
1503 extern int sock_common_setsockopt(struct socket
*sock
, int level
, int optname
,
1504 char __user
*optval
, unsigned int optlen
);
1505 extern int compat_sock_common_getsockopt(struct socket
*sock
, int level
,
1506 int optname
, char __user
*optval
, int __user
*optlen
);
1507 extern int compat_sock_common_setsockopt(struct socket
*sock
, int level
,
1508 int optname
, char __user
*optval
, unsigned int optlen
);
1510 extern void sk_common_release(struct sock
*sk
);
1513 * Default socket callbacks and setup code
1516 /* Initialise core socket variables */
1517 extern void sock_init_data(struct socket
*sock
, struct sock
*sk
);
1519 extern void sk_filter_release_rcu(struct rcu_head
*rcu
);
1522 * sk_filter_release - release a socket filter
1523 * @fp: filter to remove
1525 * Remove a filter from a socket and release its resources.
1528 static inline void sk_filter_release(struct sk_filter
*fp
)
1530 if (atomic_dec_and_test(&fp
->refcnt
))
1531 call_rcu(&fp
->rcu
, sk_filter_release_rcu
);
1534 static inline void sk_filter_uncharge(struct sock
*sk
, struct sk_filter
*fp
)
1536 unsigned int size
= sk_filter_len(fp
);
1538 atomic_sub(size
, &sk
->sk_omem_alloc
);
1539 sk_filter_release(fp
);
1542 static inline void sk_filter_charge(struct sock
*sk
, struct sk_filter
*fp
)
1544 atomic_inc(&fp
->refcnt
);
1545 atomic_add(sk_filter_len(fp
), &sk
->sk_omem_alloc
);
1549 * Socket reference counting postulates.
1551 * * Each user of socket SHOULD hold a reference count.
1552 * * Each access point to socket (an hash table bucket, reference from a list,
1553 * running timer, skb in flight MUST hold a reference count.
1554 * * When reference count hits 0, it means it will never increase back.
1555 * * When reference count hits 0, it means that no references from
1556 * outside exist to this socket and current process on current CPU
1557 * is last user and may/should destroy this socket.
1558 * * sk_free is called from any context: process, BH, IRQ. When
1559 * it is called, socket has no references from outside -> sk_free
1560 * may release descendant resources allocated by the socket, but
1561 * to the time when it is called, socket is NOT referenced by any
1562 * hash tables, lists etc.
1563 * * Packets, delivered from outside (from network or from another process)
1564 * and enqueued on receive/error queues SHOULD NOT grab reference count,
1565 * when they sit in queue. Otherwise, packets will leak to hole, when
1566 * socket is looked up by one cpu and unhasing is made by another CPU.
1567 * It is true for udp/raw, netlink (leak to receive and error queues), tcp
1568 * (leak to backlog). Packet socket does all the processing inside
1569 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
1570 * use separate SMP lock, so that they are prone too.
1573 /* Ungrab socket and destroy it, if it was the last reference. */
1574 static inline void sock_put(struct sock
*sk
)
1576 if (atomic_dec_and_test(&sk
->sk_refcnt
))
1580 extern int sk_receive_skb(struct sock
*sk
, struct sk_buff
*skb
,
1583 static inline void sk_tx_queue_set(struct sock
*sk
, int tx_queue
)
1585 sk
->sk_tx_queue_mapping
= tx_queue
;
1588 static inline void sk_tx_queue_clear(struct sock
*sk
)
1590 sk
->sk_tx_queue_mapping
= -1;
1593 static inline int sk_tx_queue_get(const struct sock
*sk
)
1595 return sk
? sk
->sk_tx_queue_mapping
: -1;
1598 static inline void sk_set_socket(struct sock
*sk
, struct socket
*sock
)
1600 sk_tx_queue_clear(sk
);
1601 sk
->sk_socket
= sock
;
1604 static inline wait_queue_head_t
*sk_sleep(struct sock
*sk
)
1606 BUILD_BUG_ON(offsetof(struct socket_wq
, wait
) != 0);
1607 return &rcu_dereference_raw(sk
->sk_wq
)->wait
;
1609 /* Detach socket from process context.
1610 * Announce socket dead, detach it from wait queue and inode.
1611 * Note that parent inode held reference count on this struct sock,
1612 * we do not release it in this function, because protocol
1613 * probably wants some additional cleanups or even continuing
1614 * to work with this socket (TCP).
1616 static inline void sock_orphan(struct sock
*sk
)
1618 write_lock_bh(&sk
->sk_callback_lock
);
1619 sock_set_flag(sk
, SOCK_DEAD
);
1620 sk_set_socket(sk
, NULL
);
1622 write_unlock_bh(&sk
->sk_callback_lock
);
1625 static inline void sock_graft(struct sock
*sk
, struct socket
*parent
)
1627 write_lock_bh(&sk
->sk_callback_lock
);
1628 sk
->sk_wq
= parent
->wq
;
1630 sk_set_socket(sk
, parent
);
1631 security_sock_graft(sk
, parent
);
1632 write_unlock_bh(&sk
->sk_callback_lock
);
1635 extern int sock_i_uid(struct sock
*sk
);
1636 extern unsigned long sock_i_ino(struct sock
*sk
);
1638 static inline struct dst_entry
*
1639 __sk_dst_get(struct sock
*sk
)
1641 return rcu_dereference_check(sk
->sk_dst_cache
, sock_owned_by_user(sk
) ||
1642 lockdep_is_held(&sk
->sk_lock
.slock
));
1645 static inline struct dst_entry
*
1646 sk_dst_get(struct sock
*sk
)
1648 struct dst_entry
*dst
;
1651 dst
= rcu_dereference(sk
->sk_dst_cache
);
1658 extern void sk_reset_txq(struct sock
*sk
);
1660 static inline void dst_negative_advice(struct sock
*sk
)
1662 struct dst_entry
*ndst
, *dst
= __sk_dst_get(sk
);
1664 if (dst
&& dst
->ops
->negative_advice
) {
1665 ndst
= dst
->ops
->negative_advice(dst
);
1668 rcu_assign_pointer(sk
->sk_dst_cache
, ndst
);
1675 __sk_dst_set(struct sock
*sk
, struct dst_entry
*dst
)
1677 struct dst_entry
*old_dst
;
1679 sk_tx_queue_clear(sk
);
1681 * This can be called while sk is owned by the caller only,
1682 * with no state that can be checked in a rcu_dereference_check() cond
1684 old_dst
= rcu_dereference_raw(sk
->sk_dst_cache
);
1685 rcu_assign_pointer(sk
->sk_dst_cache
, dst
);
1686 dst_release(old_dst
);
1690 sk_dst_set(struct sock
*sk
, struct dst_entry
*dst
)
1692 spin_lock(&sk
->sk_dst_lock
);
1693 __sk_dst_set(sk
, dst
);
1694 spin_unlock(&sk
->sk_dst_lock
);
1698 __sk_dst_reset(struct sock
*sk
)
1700 __sk_dst_set(sk
, NULL
);
1704 sk_dst_reset(struct sock
*sk
)
1706 spin_lock(&sk
->sk_dst_lock
);
1708 spin_unlock(&sk
->sk_dst_lock
);
1711 extern struct dst_entry
*__sk_dst_check(struct sock
*sk
, u32 cookie
);
1713 extern struct dst_entry
*sk_dst_check(struct sock
*sk
, u32 cookie
);
1715 static inline bool sk_can_gso(const struct sock
*sk
)
1717 return net_gso_ok(sk
->sk_route_caps
, sk
->sk_gso_type
);
1720 extern void sk_setup_caps(struct sock
*sk
, struct dst_entry
*dst
);
1722 static inline void sk_nocaps_add(struct sock
*sk
, netdev_features_t flags
)
1724 sk
->sk_route_nocaps
|= flags
;
1725 sk
->sk_route_caps
&= ~flags
;
1728 static inline int skb_do_copy_data_nocache(struct sock
*sk
, struct sk_buff
*skb
,
1729 char __user
*from
, char *to
,
1730 int copy
, int offset
)
1732 if (skb
->ip_summed
== CHECKSUM_NONE
) {
1734 __wsum csum
= csum_and_copy_from_user(from
, to
, copy
, 0, &err
);
1737 skb
->csum
= csum_block_add(skb
->csum
, csum
, offset
);
1738 } else if (sk
->sk_route_caps
& NETIF_F_NOCACHE_COPY
) {
1739 if (!access_ok(VERIFY_READ
, from
, copy
) ||
1740 __copy_from_user_nocache(to
, from
, copy
))
1742 } else if (copy_from_user(to
, from
, copy
))
1748 static inline int skb_add_data_nocache(struct sock
*sk
, struct sk_buff
*skb
,
1749 char __user
*from
, int copy
)
1751 int err
, offset
= skb
->len
;
1753 err
= skb_do_copy_data_nocache(sk
, skb
, from
, skb_put(skb
, copy
),
1756 __skb_trim(skb
, offset
);
1761 static inline int skb_copy_to_page_nocache(struct sock
*sk
, char __user
*from
,
1762 struct sk_buff
*skb
,
1768 err
= skb_do_copy_data_nocache(sk
, skb
, from
, page_address(page
) + off
,
1774 skb
->data_len
+= copy
;
1775 skb
->truesize
+= copy
;
1776 sk
->sk_wmem_queued
+= copy
;
1777 sk_mem_charge(sk
, copy
);
1781 static inline int skb_copy_to_page(struct sock
*sk
, char __user
*from
,
1782 struct sk_buff
*skb
, struct page
*page
,
1785 if (skb
->ip_summed
== CHECKSUM_NONE
) {
1787 __wsum csum
= csum_and_copy_from_user(from
,
1788 page_address(page
) + off
,
1792 skb
->csum
= csum_block_add(skb
->csum
, csum
, skb
->len
);
1793 } else if (copy_from_user(page_address(page
) + off
, from
, copy
))
1797 skb
->data_len
+= copy
;
1798 skb
->truesize
+= copy
;
1799 sk
->sk_wmem_queued
+= copy
;
1800 sk_mem_charge(sk
, copy
);
1805 * sk_wmem_alloc_get - returns write allocations
1808 * Returns sk_wmem_alloc minus initial offset of one
1810 static inline int sk_wmem_alloc_get(const struct sock
*sk
)
1812 return atomic_read(&sk
->sk_wmem_alloc
) - 1;
1816 * sk_rmem_alloc_get - returns read allocations
1819 * Returns sk_rmem_alloc
1821 static inline int sk_rmem_alloc_get(const struct sock
*sk
)
1823 return atomic_read(&sk
->sk_rmem_alloc
);
1827 * sk_has_allocations - check if allocations are outstanding
1830 * Returns true if socket has write or read allocations
1832 static inline bool sk_has_allocations(const struct sock
*sk
)
1834 return sk_wmem_alloc_get(sk
) || sk_rmem_alloc_get(sk
);
1838 * wq_has_sleeper - check if there are any waiting processes
1839 * @wq: struct socket_wq
1841 * Returns true if socket_wq has waiting processes
1843 * The purpose of the wq_has_sleeper and sock_poll_wait is to wrap the memory
1844 * barrier call. They were added due to the race found within the tcp code.
1846 * Consider following tcp code paths:
1850 * sys_select receive packet
1852 * __add_wait_queue update tp->rcv_nxt
1854 * tp->rcv_nxt check sock_def_readable
1856 * schedule rcu_read_lock();
1857 * wq = rcu_dereference(sk->sk_wq);
1858 * if (wq && waitqueue_active(&wq->wait))
1859 * wake_up_interruptible(&wq->wait)
1863 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
1864 * in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1
1865 * could then endup calling schedule and sleep forever if there are no more
1866 * data on the socket.
1869 static inline bool wq_has_sleeper(struct socket_wq
*wq
)
1871 /* We need to be sure we are in sync with the
1872 * add_wait_queue modifications to the wait queue.
1874 * This memory barrier is paired in the sock_poll_wait.
1877 return wq
&& waitqueue_active(&wq
->wait
);
1881 * sock_poll_wait - place memory barrier behind the poll_wait call.
1883 * @wait_address: socket wait queue
1886 * See the comments in the wq_has_sleeper function.
1888 static inline void sock_poll_wait(struct file
*filp
,
1889 wait_queue_head_t
*wait_address
, poll_table
*p
)
1891 if (!poll_does_not_wait(p
) && wait_address
) {
1892 poll_wait(filp
, wait_address
, p
);
1893 /* We need to be sure we are in sync with the
1894 * socket flags modification.
1896 * This memory barrier is paired in the wq_has_sleeper.
1903 * Queue a received datagram if it will fit. Stream and sequenced
1904 * protocols can't normally use this as they need to fit buffers in
1905 * and play with them.
1907 * Inlined as it's very short and called for pretty much every
1908 * packet ever received.
1911 static inline void skb_set_owner_w(struct sk_buff
*skb
, struct sock
*sk
)
1915 skb
->destructor
= sock_wfree
;
1917 * We used to take a refcount on sk, but following operation
1918 * is enough to guarantee sk_free() wont free this sock until
1919 * all in-flight packets are completed
1921 atomic_add(skb
->truesize
, &sk
->sk_wmem_alloc
);
1924 static inline void skb_set_owner_r(struct sk_buff
*skb
, struct sock
*sk
)
1928 skb
->destructor
= sock_rfree
;
1929 atomic_add(skb
->truesize
, &sk
->sk_rmem_alloc
);
1930 sk_mem_charge(sk
, skb
->truesize
);
1933 extern void sk_reset_timer(struct sock
*sk
, struct timer_list
*timer
,
1934 unsigned long expires
);
1936 extern void sk_stop_timer(struct sock
*sk
, struct timer_list
*timer
);
1938 extern int sock_queue_rcv_skb(struct sock
*sk
, struct sk_buff
*skb
);
1940 extern int sock_queue_err_skb(struct sock
*sk
, struct sk_buff
*skb
);
1943 * Recover an error report and clear atomically
1946 static inline int sock_error(struct sock
*sk
)
1949 if (likely(!sk
->sk_err
))
1951 err
= xchg(&sk
->sk_err
, 0);
1955 static inline unsigned long sock_wspace(struct sock
*sk
)
1959 if (!(sk
->sk_shutdown
& SEND_SHUTDOWN
)) {
1960 amt
= sk
->sk_sndbuf
- atomic_read(&sk
->sk_wmem_alloc
);
1967 static inline void sk_wake_async(struct sock
*sk
, int how
, int band
)
1969 if (sock_flag(sk
, SOCK_FASYNC
))
1970 sock_wake_async(sk
->sk_socket
, how
, band
);
1973 #define SOCK_MIN_SNDBUF 2048
1975 * Since sk_rmem_alloc sums skb->truesize, even a small frame might need
1976 * sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak
1978 #define SOCK_MIN_RCVBUF (2048 + sizeof(struct sk_buff))
1980 static inline void sk_stream_moderate_sndbuf(struct sock
*sk
)
1982 if (!(sk
->sk_userlocks
& SOCK_SNDBUF_LOCK
)) {
1983 sk
->sk_sndbuf
= min(sk
->sk_sndbuf
, sk
->sk_wmem_queued
>> 1);
1984 sk
->sk_sndbuf
= max(sk
->sk_sndbuf
, SOCK_MIN_SNDBUF
);
1988 struct sk_buff
*sk_stream_alloc_skb(struct sock
*sk
, int size
, gfp_t gfp
);
1990 static inline struct page
*sk_stream_alloc_page(struct sock
*sk
)
1992 struct page
*page
= NULL
;
1994 page
= alloc_pages(sk
->sk_allocation
, 0);
1996 sk_enter_memory_pressure(sk
);
1997 sk_stream_moderate_sndbuf(sk
);
2003 * Default write policy as shown to user space via poll/select/SIGIO
2005 static inline bool sock_writeable(const struct sock
*sk
)
2007 return atomic_read(&sk
->sk_wmem_alloc
) < (sk
->sk_sndbuf
>> 1);
2010 static inline gfp_t
gfp_any(void)
2012 return in_softirq() ? GFP_ATOMIC
: GFP_KERNEL
;
2015 static inline long sock_rcvtimeo(const struct sock
*sk
, bool noblock
)
2017 return noblock
? 0 : sk
->sk_rcvtimeo
;
2020 static inline long sock_sndtimeo(const struct sock
*sk
, bool noblock
)
2022 return noblock
? 0 : sk
->sk_sndtimeo
;
2025 static inline int sock_rcvlowat(const struct sock
*sk
, int waitall
, int len
)
2027 return (waitall
? len
: min_t(int, sk
->sk_rcvlowat
, len
)) ? : 1;
2030 /* Alas, with timeout socket operations are not restartable.
2031 * Compare this to poll().
2033 static inline int sock_intr_errno(long timeo
)
2035 return timeo
== MAX_SCHEDULE_TIMEOUT
? -ERESTARTSYS
: -EINTR
;
2038 extern void __sock_recv_timestamp(struct msghdr
*msg
, struct sock
*sk
,
2039 struct sk_buff
*skb
);
2040 extern void __sock_recv_wifi_status(struct msghdr
*msg
, struct sock
*sk
,
2041 struct sk_buff
*skb
);
2044 sock_recv_timestamp(struct msghdr
*msg
, struct sock
*sk
, struct sk_buff
*skb
)
2046 ktime_t kt
= skb
->tstamp
;
2047 struct skb_shared_hwtstamps
*hwtstamps
= skb_hwtstamps(skb
);
2050 * generate control messages if
2051 * - receive time stamping in software requested (SOCK_RCVTSTAMP
2052 * or SOCK_TIMESTAMPING_RX_SOFTWARE)
2053 * - software time stamp available and wanted
2054 * (SOCK_TIMESTAMPING_SOFTWARE)
2055 * - hardware time stamps available and wanted
2056 * (SOCK_TIMESTAMPING_SYS_HARDWARE or
2057 * SOCK_TIMESTAMPING_RAW_HARDWARE)
2059 if (sock_flag(sk
, SOCK_RCVTSTAMP
) ||
2060 sock_flag(sk
, SOCK_TIMESTAMPING_RX_SOFTWARE
) ||
2061 (kt
.tv64
&& sock_flag(sk
, SOCK_TIMESTAMPING_SOFTWARE
)) ||
2062 (hwtstamps
->hwtstamp
.tv64
&&
2063 sock_flag(sk
, SOCK_TIMESTAMPING_RAW_HARDWARE
)) ||
2064 (hwtstamps
->syststamp
.tv64
&&
2065 sock_flag(sk
, SOCK_TIMESTAMPING_SYS_HARDWARE
)))
2066 __sock_recv_timestamp(msg
, sk
, skb
);
2070 if (sock_flag(sk
, SOCK_WIFI_STATUS
) && skb
->wifi_acked_valid
)
2071 __sock_recv_wifi_status(msg
, sk
, skb
);
2074 extern void __sock_recv_ts_and_drops(struct msghdr
*msg
, struct sock
*sk
,
2075 struct sk_buff
*skb
);
2077 static inline void sock_recv_ts_and_drops(struct msghdr
*msg
, struct sock
*sk
,
2078 struct sk_buff
*skb
)
2080 #define FLAGS_TS_OR_DROPS ((1UL << SOCK_RXQ_OVFL) | \
2081 (1UL << SOCK_RCVTSTAMP) | \
2082 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE) | \
2083 (1UL << SOCK_TIMESTAMPING_SOFTWARE) | \
2084 (1UL << SOCK_TIMESTAMPING_RAW_HARDWARE) | \
2085 (1UL << SOCK_TIMESTAMPING_SYS_HARDWARE))
2087 if (sk
->sk_flags
& FLAGS_TS_OR_DROPS
)
2088 __sock_recv_ts_and_drops(msg
, sk
, skb
);
2090 sk
->sk_stamp
= skb
->tstamp
;
2094 * sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
2095 * @sk: socket sending this packet
2096 * @tx_flags: filled with instructions for time stamping
2098 * Currently only depends on SOCK_TIMESTAMPING* flags. Returns error code if
2099 * parameters are invalid.
2101 extern int sock_tx_timestamp(struct sock
*sk
, __u8
*tx_flags
);
2104 * sk_eat_skb - Release a skb if it is no longer needed
2105 * @sk: socket to eat this skb from
2106 * @skb: socket buffer to eat
2107 * @copied_early: flag indicating whether DMA operations copied this data early
2109 * This routine must be called with interrupts disabled or with the socket
2110 * locked so that the sk_buff queue operation is ok.
2112 #ifdef CONFIG_NET_DMA
2113 static inline void sk_eat_skb(struct sock
*sk
, struct sk_buff
*skb
, bool copied_early
)
2115 __skb_unlink(skb
, &sk
->sk_receive_queue
);
2119 __skb_queue_tail(&sk
->sk_async_wait_queue
, skb
);
2122 static inline void sk_eat_skb(struct sock
*sk
, struct sk_buff
*skb
, bool copied_early
)
2124 __skb_unlink(skb
, &sk
->sk_receive_queue
);
2130 struct net
*sock_net(const struct sock
*sk
)
2132 return read_pnet(&sk
->sk_net
);
2136 void sock_net_set(struct sock
*sk
, struct net
*net
)
2138 write_pnet(&sk
->sk_net
, net
);
2142 * Kernel sockets, f.e. rtnl or icmp_socket, are a part of a namespace.
2143 * They should not hold a reference to a namespace in order to allow
2145 * Sockets after sk_change_net should be released using sk_release_kernel
2147 static inline void sk_change_net(struct sock
*sk
, struct net
*net
)
2149 put_net(sock_net(sk
));
2150 sock_net_set(sk
, hold_net(net
));
2153 static inline struct sock
*skb_steal_sock(struct sk_buff
*skb
)
2155 if (unlikely(skb
->sk
)) {
2156 struct sock
*sk
= skb
->sk
;
2158 skb
->destructor
= NULL
;
2165 extern void sock_enable_timestamp(struct sock
*sk
, int flag
);
2166 extern int sock_get_timestamp(struct sock
*, struct timeval __user
*);
2167 extern int sock_get_timestampns(struct sock
*, struct timespec __user
*);
2170 * Enable debug/info messages
2172 extern int net_msg_warn
;
2173 #define NETDEBUG(fmt, args...) \
2174 do { if (net_msg_warn) printk(fmt,##args); } while (0)
2176 #define LIMIT_NETDEBUG(fmt, args...) \
2177 do { if (net_msg_warn && net_ratelimit()) printk(fmt,##args); } while(0)
2179 extern __u32 sysctl_wmem_max
;
2180 extern __u32 sysctl_rmem_max
;
2182 extern void sk_init(void);
2184 extern int sysctl_optmem_max
;
2186 extern __u32 sysctl_wmem_default
;
2187 extern __u32 sysctl_rmem_default
;
2189 #endif /* _SOCK_H */