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/page_counter.h>
58 #include <linux/memcontrol.h>
59 #include <linux/static_key.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>
69 #include <net/tcp_states.h>
70 #include <linux/net_tstamp.h>
75 int mem_cgroup_sockets_init(struct mem_cgroup *memcg, struct cgroup_subsys *ss);
76 void mem_cgroup_sockets_destroy(struct mem_cgroup *memcg);
79 int mem_cgroup_sockets_init(struct mem_cgroup *memcg, struct cgroup_subsys *ss)
84 void mem_cgroup_sockets_destroy(struct mem_cgroup *memcg)
89 * This structure really needs to be cleaned up.
90 * Most of it is for TCP, and not used by any of
91 * the other protocols.
94 /* Define this to get the SOCK_DBG debugging facility. */
95 #define SOCK_DEBUGGING
97 #define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \
98 printk(KERN_DEBUG msg); } while (0)
100 /* Validate arguments and do nothing */
101 static inline __printf(2, 3)
102 void SOCK_DEBUG(const struct sock *sk, const char *msg, ...)
107 /* This is the per-socket lock. The spinlock provides a synchronization
108 * between user contexts and software interrupt processing, whereas the
109 * mini-semaphore synchronizes multiple users amongst themselves.
114 wait_queue_head_t wq;
116 * We express the mutex-alike socket_lock semantics
117 * to the lock validator by explicitly managing
118 * the slock as a lock variant (in addition to
121 #ifdef CONFIG_DEBUG_LOCK_ALLOC
122 struct lockdep_map dep_map;
130 typedef __u32 __bitwise __portpair;
131 typedef __u64 __bitwise __addrpair;
134 * struct sock_common - minimal network layer representation of sockets
135 * @skc_daddr: Foreign IPv4 addr
136 * @skc_rcv_saddr: Bound local IPv4 addr
137 * @skc_hash: hash value used with various protocol lookup tables
138 * @skc_u16hashes: two u16 hash values used by UDP lookup tables
139 * @skc_dport: placeholder for inet_dport/tw_dport
140 * @skc_num: placeholder for inet_num/tw_num
141 * @skc_family: network address family
142 * @skc_state: Connection state
143 * @skc_reuse: %SO_REUSEADDR setting
144 * @skc_reuseport: %SO_REUSEPORT setting
145 * @skc_bound_dev_if: bound device index if != 0
146 * @skc_bind_node: bind hash linkage for various protocol lookup tables
147 * @skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol
148 * @skc_prot: protocol handlers inside a network family
149 * @skc_net: reference to the network namespace of this socket
150 * @skc_node: main hash linkage for various protocol lookup tables
151 * @skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol
152 * @skc_tx_queue_mapping: tx queue number for this connection
153 * @skc_flags: place holder for sk_flags
154 * %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE,
155 * %SO_OOBINLINE settings, %SO_TIMESTAMPING settings
156 * @skc_incoming_cpu: record/match cpu processing incoming packets
157 * @skc_refcnt: reference count
159 * This is the minimal network layer representation of sockets, the header
160 * for struct sock and struct inet_timewait_sock.
163 /* skc_daddr and skc_rcv_saddr must be grouped on a 8 bytes aligned
164 * address on 64bit arches : cf INET_MATCH()
167 __addrpair skc_addrpair;
170 __be32 skc_rcv_saddr;
174 unsigned int skc_hash;
175 __u16 skc_u16hashes[2];
177 /* skc_dport && skc_num must be grouped as well */
179 __portpair skc_portpair;
186 unsigned short skc_family;
187 volatile unsigned char skc_state;
188 unsigned char skc_reuse:4;
189 unsigned char skc_reuseport:1;
190 unsigned char skc_ipv6only:1;
191 unsigned char skc_net_refcnt:1;
192 int skc_bound_dev_if;
194 struct hlist_node skc_bind_node;
195 struct hlist_nulls_node skc_portaddr_node;
197 struct proto *skc_prot;
198 possible_net_t skc_net;
200 #if IS_ENABLED(CONFIG_IPV6)
201 struct in6_addr skc_v6_daddr;
202 struct in6_addr skc_v6_rcv_saddr;
205 atomic64_t skc_cookie;
207 /* following fields are padding to force
208 * offset(struct sock, sk_refcnt) == 128 on 64bit arches
209 * assuming IPV6 is enabled. We use this padding differently
210 * for different kind of 'sockets'
213 unsigned long skc_flags;
214 struct sock *skc_listener; /* request_sock */
215 struct inet_timewait_death_row *skc_tw_dr; /* inet_timewait_sock */
218 * fields between dontcopy_begin/dontcopy_end
219 * are not copied in sock_copy()
222 int skc_dontcopy_begin[0];
225 struct hlist_node skc_node;
226 struct hlist_nulls_node skc_nulls_node;
228 int skc_tx_queue_mapping;
230 int skc_incoming_cpu;
232 u32 skc_tw_rcv_nxt; /* struct tcp_timewait_sock */
237 int skc_dontcopy_end[0];
240 u32 skc_window_clamp;
241 u32 skc_tw_snd_nxt; /* struct tcp_timewait_sock */
248 * struct sock - network layer representation of sockets
249 * @__sk_common: shared layout with inet_timewait_sock
250 * @sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
251 * @sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
252 * @sk_lock: synchronizer
253 * @sk_rcvbuf: size of receive buffer in bytes
254 * @sk_wq: sock wait queue and async head
255 * @sk_rx_dst: receive input route used by early demux
256 * @sk_dst_cache: destination cache
257 * @sk_policy: flow policy
258 * @sk_receive_queue: incoming packets
259 * @sk_wmem_alloc: transmit queue bytes committed
260 * @sk_write_queue: Packet sending queue
261 * @sk_omem_alloc: "o" is "option" or "other"
262 * @sk_wmem_queued: persistent queue size
263 * @sk_forward_alloc: space allocated forward
264 * @sk_napi_id: id of the last napi context to receive data for sk
265 * @sk_ll_usec: usecs to busypoll when there is no data
266 * @sk_allocation: allocation mode
267 * @sk_pacing_rate: Pacing rate (if supported by transport/packet scheduler)
268 * @sk_max_pacing_rate: Maximum pacing rate (%SO_MAX_PACING_RATE)
269 * @sk_sndbuf: size of send buffer in bytes
270 * @sk_no_check_tx: %SO_NO_CHECK setting, set checksum in TX packets
271 * @sk_no_check_rx: allow zero checksum in RX packets
272 * @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
273 * @sk_route_nocaps: forbidden route capabilities (e.g NETIF_F_GSO_MASK)
274 * @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
275 * @sk_gso_max_size: Maximum GSO segment size to build
276 * @sk_gso_max_segs: Maximum number of GSO segments
277 * @sk_lingertime: %SO_LINGER l_linger setting
278 * @sk_backlog: always used with the per-socket spinlock held
279 * @sk_callback_lock: used with the callbacks in the end of this struct
280 * @sk_error_queue: rarely used
281 * @sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt,
282 * IPV6_ADDRFORM for instance)
283 * @sk_err: last error
284 * @sk_err_soft: errors that don't cause failure but are the cause of a
285 * persistent failure not just 'timed out'
286 * @sk_drops: raw/udp drops counter
287 * @sk_ack_backlog: current listen backlog
288 * @sk_max_ack_backlog: listen backlog set in listen()
289 * @sk_priority: %SO_PRIORITY setting
290 * @sk_cgrp_prioidx: socket group's priority map index
291 * @sk_type: socket type (%SOCK_STREAM, etc)
292 * @sk_protocol: which protocol this socket belongs in this network family
293 * @sk_peer_pid: &struct pid for this socket's peer
294 * @sk_peer_cred: %SO_PEERCRED setting
295 * @sk_rcvlowat: %SO_RCVLOWAT setting
296 * @sk_rcvtimeo: %SO_RCVTIMEO setting
297 * @sk_sndtimeo: %SO_SNDTIMEO setting
298 * @sk_txhash: computed flow hash for use on transmit
299 * @sk_filter: socket filtering instructions
300 * @sk_timer: sock cleanup timer
301 * @sk_stamp: time stamp of last packet received
302 * @sk_stamp_seq: lock for accessing sk_stamp on 32 bit architectures only
303 * @sk_tsflags: SO_TIMESTAMPING socket options
304 * @sk_tskey: counter to disambiguate concurrent tstamp requests
305 * @sk_socket: Identd and reporting IO signals
306 * @sk_user_data: RPC layer private data
307 * @sk_frag: cached page frag
308 * @sk_peek_off: current peek_offset value
309 * @sk_send_head: front of stuff to transmit
310 * @sk_security: used by security modules
311 * @sk_mark: generic packet mark
312 * @sk_classid: this socket's cgroup classid
313 * @sk_cgrp: this socket's cgroup-specific proto data
314 * @sk_write_pending: a write to stream socket waits to start
315 * @sk_state_change: callback to indicate change in the state of the sock
316 * @sk_data_ready: callback to indicate there is data to be processed
317 * @sk_write_space: callback to indicate there is bf sending space available
318 * @sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
319 * @sk_backlog_rcv: callback to process the backlog
320 * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
324 * Now struct inet_timewait_sock also uses sock_common, so please just
325 * don't add nothing before this first member (__sk_common) --acme
327 struct sock_common __sk_common;
328 #define sk_node __sk_common.skc_node
329 #define sk_nulls_node __sk_common.skc_nulls_node
330 #define sk_refcnt __sk_common.skc_refcnt
331 #define sk_tx_queue_mapping __sk_common.skc_tx_queue_mapping
333 #define sk_dontcopy_begin __sk_common.skc_dontcopy_begin
334 #define sk_dontcopy_end __sk_common.skc_dontcopy_end
335 #define sk_hash __sk_common.skc_hash
336 #define sk_portpair __sk_common.skc_portpair
337 #define sk_num __sk_common.skc_num
338 #define sk_dport __sk_common.skc_dport
339 #define sk_addrpair __sk_common.skc_addrpair
340 #define sk_daddr __sk_common.skc_daddr
341 #define sk_rcv_saddr __sk_common.skc_rcv_saddr
342 #define sk_family __sk_common.skc_family
343 #define sk_state __sk_common.skc_state
344 #define sk_reuse __sk_common.skc_reuse
345 #define sk_reuseport __sk_common.skc_reuseport
346 #define sk_ipv6only __sk_common.skc_ipv6only
347 #define sk_net_refcnt __sk_common.skc_net_refcnt
348 #define sk_bound_dev_if __sk_common.skc_bound_dev_if
349 #define sk_bind_node __sk_common.skc_bind_node
350 #define sk_prot __sk_common.skc_prot
351 #define sk_net __sk_common.skc_net
352 #define sk_v6_daddr __sk_common.skc_v6_daddr
353 #define sk_v6_rcv_saddr __sk_common.skc_v6_rcv_saddr
354 #define sk_cookie __sk_common.skc_cookie
355 #define sk_incoming_cpu __sk_common.skc_incoming_cpu
356 #define sk_flags __sk_common.skc_flags
357 #define sk_rxhash __sk_common.skc_rxhash
359 socket_lock_t sk_lock;
360 struct sk_buff_head sk_receive_queue;
362 * The backlog queue is special, it is always used with
363 * the per-socket spinlock held and requires low latency
364 * access. Therefore we special case it's implementation.
365 * Note : rmem_alloc is in this structure to fill a hole
366 * on 64bit arches, not because its logically part of
372 struct sk_buff *head;
373 struct sk_buff *tail;
375 #define sk_rmem_alloc sk_backlog.rmem_alloc
376 int sk_forward_alloc;
379 #ifdef CONFIG_NET_RX_BUSY_POLL
380 unsigned int sk_napi_id;
381 unsigned int sk_ll_usec;
386 struct sk_filter __rcu *sk_filter;
388 struct socket_wq __rcu *sk_wq;
389 struct socket_wq *sk_wq_raw;
392 struct xfrm_policy __rcu *sk_policy[2];
394 struct dst_entry *sk_rx_dst;
395 struct dst_entry __rcu *sk_dst_cache;
396 /* Note: 32bit hole on 64bit arches */
397 atomic_t sk_wmem_alloc;
398 atomic_t sk_omem_alloc;
400 struct sk_buff_head sk_write_queue;
401 kmemcheck_bitfield_begin(flags);
402 unsigned int sk_shutdown : 2,
408 #define SK_PROTOCOL_MAX U8_MAX
409 kmemcheck_bitfield_end(flags);
412 u32 sk_pacing_rate; /* bytes per second */
413 u32 sk_max_pacing_rate;
414 netdev_features_t sk_route_caps;
415 netdev_features_t sk_route_nocaps;
417 unsigned int sk_gso_max_size;
420 unsigned long sk_lingertime;
421 struct sk_buff_head sk_error_queue;
422 struct proto *sk_prot_creator;
423 rwlock_t sk_callback_lock;
427 u32 sk_max_ack_backlog;
429 #if IS_ENABLED(CONFIG_CGROUP_NET_PRIO)
430 __u32 sk_cgrp_prioidx;
432 struct pid *sk_peer_pid;
433 const struct cred *sk_peer_cred;
436 struct timer_list sk_timer;
438 #if BITS_PER_LONG==32
439 seqlock_t sk_stamp_seq;
443 struct socket *sk_socket;
445 struct page_frag sk_frag;
446 struct sk_buff *sk_send_head;
448 int sk_write_pending;
449 #ifdef CONFIG_SECURITY
454 #ifdef CONFIG_CGROUP_NET_CLASSID
457 struct cg_proto *sk_cgrp;
458 void (*sk_state_change)(struct sock *sk);
459 void (*sk_data_ready)(struct sock *sk);
460 void (*sk_write_space)(struct sock *sk);
461 void (*sk_error_report)(struct sock *sk);
462 int (*sk_backlog_rcv)(struct sock *sk,
463 struct sk_buff *skb);
464 void (*sk_destruct)(struct sock *sk);
465 struct rcu_head sk_rcu;
468 #define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data)))
470 #define rcu_dereference_sk_user_data(sk) rcu_dereference(__sk_user_data((sk)))
471 #define rcu_assign_sk_user_data(sk, ptr) rcu_assign_pointer(__sk_user_data((sk)), ptr)
474 * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK
475 * or not whether his port will be reused by someone else. SK_FORCE_REUSE
476 * on a socket means that the socket will reuse everybody else's port
477 * without looking at the other's sk_reuse value.
480 #define SK_NO_REUSE 0
481 #define SK_CAN_REUSE 1
482 #define SK_FORCE_REUSE 2
484 static inline int sk_peek_offset(struct sock *sk, int flags)
486 if ((flags & MSG_PEEK) && (sk->sk_peek_off >= 0))
487 return sk->sk_peek_off;
492 static inline void sk_peek_offset_bwd(struct sock *sk, int val)
494 if (sk->sk_peek_off >= 0) {
495 if (sk->sk_peek_off >= val)
496 sk->sk_peek_off -= val;
502 static inline void sk_peek_offset_fwd(struct sock *sk, int val)
504 if (sk->sk_peek_off >= 0)
505 sk->sk_peek_off += val;
509 * Hashed lists helper routines
511 static inline struct sock *sk_entry(const struct hlist_node *node)
513 return hlist_entry(node, struct sock, sk_node);
516 static inline struct sock *__sk_head(const struct hlist_head *head)
518 return hlist_entry(head->first, struct sock, sk_node);
521 static inline struct sock *sk_head(const struct hlist_head *head)
523 return hlist_empty(head) ? NULL : __sk_head(head);
526 static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head)
528 return hlist_nulls_entry(head->first, struct sock, sk_nulls_node);
531 static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head)
533 return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head);
536 static inline struct sock *sk_next(const struct sock *sk)
538 return sk->sk_node.next ?
539 hlist_entry(sk->sk_node.next, struct sock, sk_node) : NULL;
542 static inline struct sock *sk_nulls_next(const struct sock *sk)
544 return (!is_a_nulls(sk->sk_nulls_node.next)) ?
545 hlist_nulls_entry(sk->sk_nulls_node.next,
546 struct sock, sk_nulls_node) :
550 static inline bool sk_unhashed(const struct sock *sk)
552 return hlist_unhashed(&sk->sk_node);
555 static inline bool sk_hashed(const struct sock *sk)
557 return !sk_unhashed(sk);
560 static inline void sk_node_init(struct hlist_node *node)
565 static inline void sk_nulls_node_init(struct hlist_nulls_node *node)
570 static inline void __sk_del_node(struct sock *sk)
572 __hlist_del(&sk->sk_node);
575 /* NB: equivalent to hlist_del_init_rcu */
576 static inline bool __sk_del_node_init(struct sock *sk)
580 sk_node_init(&sk->sk_node);
586 /* Grab socket reference count. This operation is valid only
587 when sk is ALREADY grabbed f.e. it is found in hash table
588 or a list and the lookup is made under lock preventing hash table
592 static inline void sock_hold(struct sock *sk)
594 atomic_inc(&sk->sk_refcnt);
597 /* Ungrab socket in the context, which assumes that socket refcnt
598 cannot hit zero, f.e. it is true in context of any socketcall.
600 static inline void __sock_put(struct sock *sk)
602 atomic_dec(&sk->sk_refcnt);
605 static inline bool sk_del_node_init(struct sock *sk)
607 bool rc = __sk_del_node_init(sk);
610 /* paranoid for a while -acme */
611 WARN_ON(atomic_read(&sk->sk_refcnt) == 1);
616 #define sk_del_node_init_rcu(sk) sk_del_node_init(sk)
618 static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk)
621 hlist_nulls_del_init_rcu(&sk->sk_nulls_node);
627 static inline bool sk_nulls_del_node_init_rcu(struct sock *sk)
629 bool rc = __sk_nulls_del_node_init_rcu(sk);
632 /* paranoid for a while -acme */
633 WARN_ON(atomic_read(&sk->sk_refcnt) == 1);
639 static inline void __sk_add_node(struct sock *sk, struct hlist_head *list)
641 hlist_add_head(&sk->sk_node, list);
644 static inline void sk_add_node(struct sock *sk, struct hlist_head *list)
647 __sk_add_node(sk, list);
650 static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list)
653 hlist_add_head_rcu(&sk->sk_node, list);
656 static inline void sk_add_node_tail_rcu(struct sock *sk, struct hlist_head *list)
659 hlist_add_tail_rcu(&sk->sk_node, list);
662 static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
664 hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list);
667 static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
670 __sk_nulls_add_node_rcu(sk, list);
673 static inline void __sk_del_bind_node(struct sock *sk)
675 __hlist_del(&sk->sk_bind_node);
678 static inline void sk_add_bind_node(struct sock *sk,
679 struct hlist_head *list)
681 hlist_add_head(&sk->sk_bind_node, list);
684 #define sk_for_each(__sk, list) \
685 hlist_for_each_entry(__sk, list, sk_node)
686 #define sk_for_each_rcu(__sk, list) \
687 hlist_for_each_entry_rcu(__sk, list, sk_node)
688 #define sk_nulls_for_each(__sk, node, list) \
689 hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)
690 #define sk_nulls_for_each_rcu(__sk, node, list) \
691 hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)
692 #define sk_for_each_from(__sk) \
693 hlist_for_each_entry_from(__sk, sk_node)
694 #define sk_nulls_for_each_from(__sk, node) \
695 if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \
696 hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node)
697 #define sk_for_each_safe(__sk, tmp, list) \
698 hlist_for_each_entry_safe(__sk, tmp, list, sk_node)
699 #define sk_for_each_bound(__sk, list) \
700 hlist_for_each_entry(__sk, list, sk_bind_node)
703 * sk_nulls_for_each_entry_offset - iterate over a list at a given struct offset
704 * @tpos: the type * to use as a loop cursor.
705 * @pos: the &struct hlist_node to use as a loop cursor.
706 * @head: the head for your list.
707 * @offset: offset of hlist_node within the struct.
710 #define sk_nulls_for_each_entry_offset(tpos, pos, head, offset) \
711 for (pos = (head)->first; \
712 (!is_a_nulls(pos)) && \
713 ({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;}); \
716 static inline struct user_namespace *sk_user_ns(struct sock *sk)
718 /* Careful only use this in a context where these parameters
719 * can not change and must all be valid, such as recvmsg from
722 return sk->sk_socket->file->f_cred->user_ns;
736 SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */
737 SOCK_DBG, /* %SO_DEBUG setting */
738 SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
739 SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */
740 SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
741 SOCK_QUEUE_SHRUNK, /* write queue has been shrunk recently */
742 SOCK_MEMALLOC, /* VM depends on this socket for swapping */
743 SOCK_TIMESTAMPING_RX_SOFTWARE, /* %SOF_TIMESTAMPING_RX_SOFTWARE */
744 SOCK_FASYNC, /* fasync() active */
746 SOCK_ZEROCOPY, /* buffers from userspace */
747 SOCK_WIFI_STATUS, /* push wifi status to userspace */
748 SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS.
749 * Will use last 4 bytes of packet sent from
750 * user-space instead.
752 SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */
753 SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */
754 SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */
757 #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))
759 static inline void sock_copy_flags(struct sock *nsk, struct sock *osk)
761 nsk->sk_flags = osk->sk_flags;
764 static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
766 __set_bit(flag, &sk->sk_flags);
769 static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag)
771 __clear_bit(flag, &sk->sk_flags);
774 static inline bool sock_flag(const struct sock *sk, enum sock_flags flag)
776 return test_bit(flag, &sk->sk_flags);
780 extern struct static_key memalloc_socks;
781 static inline int sk_memalloc_socks(void)
783 return static_key_false(&memalloc_socks);
787 static inline int sk_memalloc_socks(void)
794 static inline gfp_t sk_gfp_atomic(const struct sock *sk, gfp_t gfp_mask)
796 return GFP_ATOMIC | (sk->sk_allocation & __GFP_MEMALLOC);
799 static inline void sk_acceptq_removed(struct sock *sk)
801 sk->sk_ack_backlog--;
804 static inline void sk_acceptq_added(struct sock *sk)
806 sk->sk_ack_backlog++;
809 static inline bool sk_acceptq_is_full(const struct sock *sk)
811 return sk->sk_ack_backlog > sk->sk_max_ack_backlog;
815 * Compute minimal free write space needed to queue new packets.
817 static inline int sk_stream_min_wspace(const struct sock *sk)
819 return sk->sk_wmem_queued >> 1;
822 static inline int sk_stream_wspace(const struct sock *sk)
824 return sk->sk_sndbuf - sk->sk_wmem_queued;
827 void sk_stream_write_space(struct sock *sk);
829 /* OOB backlog add */
830 static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
832 /* dont let skb dst not refcounted, we are going to leave rcu lock */
833 skb_dst_force_safe(skb);
835 if (!sk->sk_backlog.tail)
836 sk->sk_backlog.head = skb;
838 sk->sk_backlog.tail->next = skb;
840 sk->sk_backlog.tail = skb;
845 * Take into account size of receive queue and backlog queue
846 * Do not take into account this skb truesize,
847 * to allow even a single big packet to come.
849 static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit)
851 unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc);
853 return qsize > limit;
856 /* The per-socket spinlock must be held here. */
857 static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb,
860 if (sk_rcvqueues_full(sk, limit))
864 * If the skb was allocated from pfmemalloc reserves, only
865 * allow SOCK_MEMALLOC sockets to use it as this socket is
866 * helping free memory
868 if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC))
871 __sk_add_backlog(sk, skb);
872 sk->sk_backlog.len += skb->truesize;
876 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb);
878 static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
880 if (sk_memalloc_socks() && skb_pfmemalloc(skb))
881 return __sk_backlog_rcv(sk, skb);
883 return sk->sk_backlog_rcv(sk, skb);
886 static inline void sk_incoming_cpu_update(struct sock *sk)
888 sk->sk_incoming_cpu = raw_smp_processor_id();
891 static inline void sock_rps_record_flow_hash(__u32 hash)
894 struct rps_sock_flow_table *sock_flow_table;
897 sock_flow_table = rcu_dereference(rps_sock_flow_table);
898 rps_record_sock_flow(sock_flow_table, hash);
903 static inline void sock_rps_record_flow(const struct sock *sk)
906 sock_rps_record_flow_hash(sk->sk_rxhash);
910 static inline void sock_rps_save_rxhash(struct sock *sk,
911 const struct sk_buff *skb)
914 if (unlikely(sk->sk_rxhash != skb->hash))
915 sk->sk_rxhash = skb->hash;
919 static inline void sock_rps_reset_rxhash(struct sock *sk)
926 #define sk_wait_event(__sk, __timeo, __condition) \
928 release_sock(__sk); \
929 __rc = __condition; \
931 *(__timeo) = schedule_timeout(*(__timeo)); \
933 sched_annotate_sleep(); \
935 __rc = __condition; \
939 int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
940 int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
941 void sk_stream_wait_close(struct sock *sk, long timeo_p);
942 int sk_stream_error(struct sock *sk, int flags, int err);
943 void sk_stream_kill_queues(struct sock *sk);
944 void sk_set_memalloc(struct sock *sk);
945 void sk_clear_memalloc(struct sock *sk);
947 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb);
949 struct request_sock_ops;
950 struct timewait_sock_ops;
951 struct inet_hashinfo;
956 * caches using SLAB_DESTROY_BY_RCU should let .next pointer from nulls nodes
957 * un-modified. Special care is taken when initializing object to zero.
959 static inline void sk_prot_clear_nulls(struct sock *sk, int size)
961 if (offsetof(struct sock, sk_node.next) != 0)
962 memset(sk, 0, offsetof(struct sock, sk_node.next));
963 memset(&sk->sk_node.pprev, 0,
964 size - offsetof(struct sock, sk_node.pprev));
967 /* Networking protocol blocks we attach to sockets.
968 * socket layer -> transport layer interface
971 void (*close)(struct sock *sk,
973 int (*connect)(struct sock *sk,
974 struct sockaddr *uaddr,
976 int (*disconnect)(struct sock *sk, int flags);
978 struct sock * (*accept)(struct sock *sk, int flags, int *err);
980 int (*ioctl)(struct sock *sk, int cmd,
982 int (*init)(struct sock *sk);
983 void (*destroy)(struct sock *sk);
984 void (*shutdown)(struct sock *sk, int how);
985 int (*setsockopt)(struct sock *sk, int level,
986 int optname, char __user *optval,
987 unsigned int optlen);
988 int (*getsockopt)(struct sock *sk, int level,
989 int optname, char __user *optval,
992 int (*compat_setsockopt)(struct sock *sk,
994 int optname, char __user *optval,
995 unsigned int optlen);
996 int (*compat_getsockopt)(struct sock *sk,
998 int optname, char __user *optval,
1000 int (*compat_ioctl)(struct sock *sk,
1001 unsigned int cmd, unsigned long arg);
1003 int (*sendmsg)(struct sock *sk, struct msghdr *msg,
1005 int (*recvmsg)(struct sock *sk, struct msghdr *msg,
1006 size_t len, int noblock, int flags,
1008 int (*sendpage)(struct sock *sk, struct page *page,
1009 int offset, size_t size, int flags);
1010 int (*bind)(struct sock *sk,
1011 struct sockaddr *uaddr, int addr_len);
1013 int (*backlog_rcv) (struct sock *sk,
1014 struct sk_buff *skb);
1016 void (*release_cb)(struct sock *sk);
1018 /* Keeping track of sk's, looking them up, and port selection methods. */
1019 void (*hash)(struct sock *sk);
1020 void (*unhash)(struct sock *sk);
1021 void (*rehash)(struct sock *sk);
1022 int (*get_port)(struct sock *sk, unsigned short snum);
1023 void (*clear_sk)(struct sock *sk, int size);
1025 /* Keeping track of sockets in use */
1026 #ifdef CONFIG_PROC_FS
1027 unsigned int inuse_idx;
1030 bool (*stream_memory_free)(const struct sock *sk);
1031 /* Memory pressure */
1032 void (*enter_memory_pressure)(struct sock *sk);
1033 atomic_long_t *memory_allocated; /* Current allocated memory. */
1034 struct percpu_counter *sockets_allocated; /* Current number of sockets. */
1036 * Pressure flag: try to collapse.
1037 * Technical note: it is used by multiple contexts non atomically.
1038 * All the __sk_mem_schedule() is of this nature: accounting
1039 * is strict, actions are advisory and have some latency.
1041 int *memory_pressure;
1048 struct kmem_cache *slab;
1049 unsigned int obj_size;
1052 struct percpu_counter *orphan_count;
1054 struct request_sock_ops *rsk_prot;
1055 struct timewait_sock_ops *twsk_prot;
1058 struct inet_hashinfo *hashinfo;
1059 struct udp_table *udp_table;
1060 struct raw_hashinfo *raw_hash;
1063 struct module *owner;
1067 struct list_head node;
1068 #ifdef SOCK_REFCNT_DEBUG
1071 #ifdef CONFIG_MEMCG_KMEM
1073 * cgroup specific init/deinit functions. Called once for all
1074 * protocols that implement it, from cgroups populate function.
1075 * This function has to setup any files the protocol want to
1076 * appear in the kmem cgroup filesystem.
1078 int (*init_cgroup)(struct mem_cgroup *memcg,
1079 struct cgroup_subsys *ss);
1080 void (*destroy_cgroup)(struct mem_cgroup *memcg);
1081 struct cg_proto *(*proto_cgroup)(struct mem_cgroup *memcg);
1083 int (*diag_destroy)(struct sock *sk, int err);
1086 int proto_register(struct proto *prot, int alloc_slab);
1087 void proto_unregister(struct proto *prot);
1089 #ifdef SOCK_REFCNT_DEBUG
1090 static inline void sk_refcnt_debug_inc(struct sock *sk)
1092 atomic_inc(&sk->sk_prot->socks);
1095 static inline void sk_refcnt_debug_dec(struct sock *sk)
1097 atomic_dec(&sk->sk_prot->socks);
1098 printk(KERN_DEBUG "%s socket %p released, %d are still alive\n",
1099 sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks));
1102 static inline void sk_refcnt_debug_release(const struct sock *sk)
1104 if (atomic_read(&sk->sk_refcnt) != 1)
1105 printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n",
1106 sk->sk_prot->name, sk, atomic_read(&sk->sk_refcnt));
1108 #else /* SOCK_REFCNT_DEBUG */
1109 #define sk_refcnt_debug_inc(sk) do { } while (0)
1110 #define sk_refcnt_debug_dec(sk) do { } while (0)
1111 #define sk_refcnt_debug_release(sk) do { } while (0)
1112 #endif /* SOCK_REFCNT_DEBUG */
1114 #if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_NET)
1115 extern struct static_key memcg_socket_limit_enabled;
1116 static inline struct cg_proto *parent_cg_proto(struct proto *proto,
1117 struct cg_proto *cg_proto)
1119 return proto->proto_cgroup(parent_mem_cgroup(cg_proto->memcg));
1121 #define mem_cgroup_sockets_enabled static_key_false(&memcg_socket_limit_enabled)
1123 #define mem_cgroup_sockets_enabled 0
1124 static inline struct cg_proto *parent_cg_proto(struct proto *proto,
1125 struct cg_proto *cg_proto)
1131 static inline bool sk_stream_memory_free(const struct sock *sk)
1133 if (sk->sk_wmem_queued >= sk->sk_sndbuf)
1136 return sk->sk_prot->stream_memory_free ?
1137 sk->sk_prot->stream_memory_free(sk) : true;
1140 static inline bool sk_stream_is_writeable(const struct sock *sk)
1142 return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) &&
1143 sk_stream_memory_free(sk);
1147 static inline bool sk_has_memory_pressure(const struct sock *sk)
1149 return sk->sk_prot->memory_pressure != NULL;
1152 static inline bool sk_under_memory_pressure(const struct sock *sk)
1154 if (!sk->sk_prot->memory_pressure)
1157 if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1158 return !!sk->sk_cgrp->memory_pressure;
1160 return !!*sk->sk_prot->memory_pressure;
1163 static inline void sk_leave_memory_pressure(struct sock *sk)
1165 int *memory_pressure = sk->sk_prot->memory_pressure;
1167 if (!memory_pressure)
1170 if (*memory_pressure)
1171 *memory_pressure = 0;
1173 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1174 struct cg_proto *cg_proto = sk->sk_cgrp;
1175 struct proto *prot = sk->sk_prot;
1177 for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto))
1178 cg_proto->memory_pressure = 0;
1183 static inline void sk_enter_memory_pressure(struct sock *sk)
1185 if (!sk->sk_prot->enter_memory_pressure)
1188 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1189 struct cg_proto *cg_proto = sk->sk_cgrp;
1190 struct proto *prot = sk->sk_prot;
1192 for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto))
1193 cg_proto->memory_pressure = 1;
1196 sk->sk_prot->enter_memory_pressure(sk);
1199 static inline long sk_prot_mem_limits(const struct sock *sk, int index)
1201 long *prot = sk->sk_prot->sysctl_mem;
1202 if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1203 prot = sk->sk_cgrp->sysctl_mem;
1207 static inline void memcg_memory_allocated_add(struct cg_proto *prot,
1211 page_counter_charge(&prot->memory_allocated, amt);
1213 if (page_counter_read(&prot->memory_allocated) >
1214 prot->memory_allocated.limit)
1215 *parent_status = OVER_LIMIT;
1218 static inline void memcg_memory_allocated_sub(struct cg_proto *prot,
1221 page_counter_uncharge(&prot->memory_allocated, amt);
1225 sk_memory_allocated(const struct sock *sk)
1227 struct proto *prot = sk->sk_prot;
1229 if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1230 return page_counter_read(&sk->sk_cgrp->memory_allocated);
1232 return atomic_long_read(prot->memory_allocated);
1236 sk_memory_allocated_add(struct sock *sk, int amt, int *parent_status)
1238 struct proto *prot = sk->sk_prot;
1240 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1241 memcg_memory_allocated_add(sk->sk_cgrp, amt, parent_status);
1242 /* update the root cgroup regardless */
1243 atomic_long_add_return(amt, prot->memory_allocated);
1244 return page_counter_read(&sk->sk_cgrp->memory_allocated);
1247 return atomic_long_add_return(amt, prot->memory_allocated);
1251 sk_memory_allocated_sub(struct sock *sk, int amt)
1253 struct proto *prot = sk->sk_prot;
1255 if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1256 memcg_memory_allocated_sub(sk->sk_cgrp, amt);
1258 atomic_long_sub(amt, prot->memory_allocated);
1261 static inline void sk_sockets_allocated_dec(struct sock *sk)
1263 struct proto *prot = sk->sk_prot;
1265 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1266 struct cg_proto *cg_proto = sk->sk_cgrp;
1268 for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto))
1269 percpu_counter_dec(&cg_proto->sockets_allocated);
1272 percpu_counter_dec(prot->sockets_allocated);
1275 static inline void sk_sockets_allocated_inc(struct sock *sk)
1277 struct proto *prot = sk->sk_prot;
1279 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1280 struct cg_proto *cg_proto = sk->sk_cgrp;
1282 for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto))
1283 percpu_counter_inc(&cg_proto->sockets_allocated);
1286 percpu_counter_inc(prot->sockets_allocated);
1290 sk_sockets_allocated_read_positive(struct sock *sk)
1292 struct proto *prot = sk->sk_prot;
1294 if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1295 return percpu_counter_read_positive(&sk->sk_cgrp->sockets_allocated);
1297 return percpu_counter_read_positive(prot->sockets_allocated);
1301 proto_sockets_allocated_sum_positive(struct proto *prot)
1303 return percpu_counter_sum_positive(prot->sockets_allocated);
1307 proto_memory_allocated(struct proto *prot)
1309 return atomic_long_read(prot->memory_allocated);
1313 proto_memory_pressure(struct proto *prot)
1315 if (!prot->memory_pressure)
1317 return !!*prot->memory_pressure;
1321 #ifdef CONFIG_PROC_FS
1322 /* Called with local bh disabled */
1323 void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc);
1324 int sock_prot_inuse_get(struct net *net, struct proto *proto);
1326 static inline void sock_prot_inuse_add(struct net *net, struct proto *prot,
1333 /* With per-bucket locks this operation is not-atomic, so that
1334 * this version is not worse.
1336 static inline void __sk_prot_rehash(struct sock *sk)
1338 sk->sk_prot->unhash(sk);
1339 sk->sk_prot->hash(sk);
1342 void sk_prot_clear_portaddr_nulls(struct sock *sk, int size);
1344 /* About 10 seconds */
1345 #define SOCK_DESTROY_TIME (10*HZ)
1347 /* Sockets 0-1023 can't be bound to unless you are superuser */
1348 #define PROT_SOCK 1024
1350 #define SHUTDOWN_MASK 3
1351 #define RCV_SHUTDOWN 1
1352 #define SEND_SHUTDOWN 2
1354 #define SOCK_SNDBUF_LOCK 1
1355 #define SOCK_RCVBUF_LOCK 2
1356 #define SOCK_BINDADDR_LOCK 4
1357 #define SOCK_BINDPORT_LOCK 8
1359 struct socket_alloc {
1360 struct socket socket;
1361 struct inode vfs_inode;
1364 static inline struct socket *SOCKET_I(struct inode *inode)
1366 return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
1369 static inline struct inode *SOCK_INODE(struct socket *socket)
1371 return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
1375 * Functions for memory accounting
1377 int __sk_mem_schedule(struct sock *sk, int size, int kind);
1378 void __sk_mem_reclaim(struct sock *sk, int amount);
1380 #define SK_MEM_QUANTUM ((int)PAGE_SIZE)
1381 #define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM)
1382 #define SK_MEM_SEND 0
1383 #define SK_MEM_RECV 1
1385 static inline int sk_mem_pages(int amt)
1387 return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT;
1390 static inline bool sk_has_account(struct sock *sk)
1392 /* return true if protocol supports memory accounting */
1393 return !!sk->sk_prot->memory_allocated;
1396 static inline bool sk_wmem_schedule(struct sock *sk, int size)
1398 if (!sk_has_account(sk))
1400 return size <= sk->sk_forward_alloc ||
1401 __sk_mem_schedule(sk, size, SK_MEM_SEND);
1405 sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size)
1407 if (!sk_has_account(sk))
1409 return size<= sk->sk_forward_alloc ||
1410 __sk_mem_schedule(sk, size, SK_MEM_RECV) ||
1411 skb_pfmemalloc(skb);
1414 static inline void sk_mem_reclaim(struct sock *sk)
1416 if (!sk_has_account(sk))
1418 if (sk->sk_forward_alloc >= SK_MEM_QUANTUM)
1419 __sk_mem_reclaim(sk, sk->sk_forward_alloc);
1422 static inline void sk_mem_reclaim_partial(struct sock *sk)
1424 if (!sk_has_account(sk))
1426 if (sk->sk_forward_alloc > SK_MEM_QUANTUM)
1427 __sk_mem_reclaim(sk, sk->sk_forward_alloc - 1);
1430 static inline void sk_mem_charge(struct sock *sk, int size)
1432 if (!sk_has_account(sk))
1434 sk->sk_forward_alloc -= size;
1437 static inline void sk_mem_uncharge(struct sock *sk, int size)
1439 if (!sk_has_account(sk))
1441 sk->sk_forward_alloc += size;
1443 /* Avoid a possible overflow.
1444 * TCP send queues can make this happen, if sk_mem_reclaim()
1445 * is not called and more than 2 GBytes are released at once.
1447 * If we reach 2 MBytes, reclaim 1 MBytes right now, there is
1448 * no need to hold that much forward allocation anyway.
1450 if (unlikely(sk->sk_forward_alloc >= 1 << 21))
1451 __sk_mem_reclaim(sk, 1 << 20);
1454 static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb)
1456 sock_set_flag(sk, SOCK_QUEUE_SHRUNK);
1457 sk->sk_wmem_queued -= skb->truesize;
1458 sk_mem_uncharge(sk, skb->truesize);
1462 /* Used by processes to "lock" a socket state, so that
1463 * interrupts and bottom half handlers won't change it
1464 * from under us. It essentially blocks any incoming
1465 * packets, so that we won't get any new data or any
1466 * packets that change the state of the socket.
1468 * While locked, BH processing will add new packets to
1469 * the backlog queue. This queue is processed by the
1470 * owner of the socket lock right before it is released.
1472 * Since ~2.3.5 it is also exclusive sleep lock serializing
1473 * accesses from user process context.
1475 #define sock_owned_by_user(sk) ((sk)->sk_lock.owned)
1477 static inline void sock_release_ownership(struct sock *sk)
1479 sk->sk_lock.owned = 0;
1483 * Macro so as to not evaluate some arguments when
1484 * lockdep is not enabled.
1486 * Mark both the sk_lock and the sk_lock.slock as a
1487 * per-address-family lock class.
1489 #define sock_lock_init_class_and_name(sk, sname, skey, name, key) \
1491 sk->sk_lock.owned = 0; \
1492 init_waitqueue_head(&sk->sk_lock.wq); \
1493 spin_lock_init(&(sk)->sk_lock.slock); \
1494 debug_check_no_locks_freed((void *)&(sk)->sk_lock, \
1495 sizeof((sk)->sk_lock)); \
1496 lockdep_set_class_and_name(&(sk)->sk_lock.slock, \
1498 lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \
1501 void lock_sock_nested(struct sock *sk, int subclass);
1503 static inline void lock_sock(struct sock *sk)
1505 lock_sock_nested(sk, 0);
1508 void release_sock(struct sock *sk);
1510 /* BH context may only use the following locking interface. */
1511 #define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock))
1512 #define bh_lock_sock_nested(__sk) \
1513 spin_lock_nested(&((__sk)->sk_lock.slock), \
1514 SINGLE_DEPTH_NESTING)
1515 #define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock))
1517 bool lock_sock_fast(struct sock *sk);
1519 * unlock_sock_fast - complement of lock_sock_fast
1523 * fast unlock socket for user context.
1524 * If slow mode is on, we call regular release_sock()
1526 static inline void unlock_sock_fast(struct sock *sk, bool slow)
1531 spin_unlock_bh(&sk->sk_lock.slock);
1535 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1536 struct proto *prot, int kern);
1537 void sk_free(struct sock *sk);
1538 void sk_destruct(struct sock *sk);
1539 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority);
1541 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1543 void sock_wfree(struct sk_buff *skb);
1544 void skb_orphan_partial(struct sk_buff *skb);
1545 void sock_rfree(struct sk_buff *skb);
1546 void sock_efree(struct sk_buff *skb);
1548 void sock_edemux(struct sk_buff *skb);
1550 #define sock_edemux(skb) sock_efree(skb)
1553 int sock_setsockopt(struct socket *sock, int level, int op,
1554 char __user *optval, unsigned int optlen);
1556 int sock_getsockopt(struct socket *sock, int level, int op,
1557 char __user *optval, int __user *optlen);
1558 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1559 int noblock, int *errcode);
1560 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1561 unsigned long data_len, int noblock,
1562 int *errcode, int max_page_order);
1563 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority);
1564 void sock_kfree_s(struct sock *sk, void *mem, int size);
1565 void sock_kzfree_s(struct sock *sk, void *mem, int size);
1566 void sk_send_sigurg(struct sock *sk);
1568 struct sockcm_cookie {
1572 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
1573 struct sockcm_cookie *sockc);
1576 * Functions to fill in entries in struct proto_ops when a protocol
1577 * does not implement a particular function.
1579 int sock_no_bind(struct socket *, struct sockaddr *, int);
1580 int sock_no_connect(struct socket *, struct sockaddr *, int, int);
1581 int sock_no_socketpair(struct socket *, struct socket *);
1582 int sock_no_accept(struct socket *, struct socket *, int);
1583 int sock_no_getname(struct socket *, struct sockaddr *, int *, int);
1584 unsigned int sock_no_poll(struct file *, struct socket *,
1585 struct poll_table_struct *);
1586 int sock_no_ioctl(struct socket *, unsigned int, unsigned long);
1587 int sock_no_listen(struct socket *, int);
1588 int sock_no_shutdown(struct socket *, int);
1589 int sock_no_getsockopt(struct socket *, int , int, char __user *, int __user *);
1590 int sock_no_setsockopt(struct socket *, int, int, char __user *, unsigned int);
1591 int sock_no_sendmsg(struct socket *, struct msghdr *, size_t);
1592 int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int);
1593 int sock_no_mmap(struct file *file, struct socket *sock,
1594 struct vm_area_struct *vma);
1595 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset,
1596 size_t size, int flags);
1599 * Functions to fill in entries in struct proto_ops when a protocol
1600 * uses the inet style.
1602 int sock_common_getsockopt(struct socket *sock, int level, int optname,
1603 char __user *optval, int __user *optlen);
1604 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1606 int sock_common_setsockopt(struct socket *sock, int level, int optname,
1607 char __user *optval, unsigned int optlen);
1608 int compat_sock_common_getsockopt(struct socket *sock, int level,
1609 int optname, char __user *optval, int __user *optlen);
1610 int compat_sock_common_setsockopt(struct socket *sock, int level,
1611 int optname, char __user *optval, unsigned int optlen);
1613 void sk_common_release(struct sock *sk);
1616 * Default socket callbacks and setup code
1619 /* Initialise core socket variables */
1620 void sock_init_data(struct socket *sock, struct sock *sk);
1623 * Socket reference counting postulates.
1625 * * Each user of socket SHOULD hold a reference count.
1626 * * Each access point to socket (an hash table bucket, reference from a list,
1627 * running timer, skb in flight MUST hold a reference count.
1628 * * When reference count hits 0, it means it will never increase back.
1629 * * When reference count hits 0, it means that no references from
1630 * outside exist to this socket and current process on current CPU
1631 * is last user and may/should destroy this socket.
1632 * * sk_free is called from any context: process, BH, IRQ. When
1633 * it is called, socket has no references from outside -> sk_free
1634 * may release descendant resources allocated by the socket, but
1635 * to the time when it is called, socket is NOT referenced by any
1636 * hash tables, lists etc.
1637 * * Packets, delivered from outside (from network or from another process)
1638 * and enqueued on receive/error queues SHOULD NOT grab reference count,
1639 * when they sit in queue. Otherwise, packets will leak to hole, when
1640 * socket is looked up by one cpu and unhasing is made by another CPU.
1641 * It is true for udp/raw, netlink (leak to receive and error queues), tcp
1642 * (leak to backlog). Packet socket does all the processing inside
1643 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
1644 * use separate SMP lock, so that they are prone too.
1647 /* Ungrab socket and destroy it, if it was the last reference. */
1648 static inline void sock_put(struct sock *sk)
1650 if (atomic_dec_and_test(&sk->sk_refcnt))
1653 /* Generic version of sock_put(), dealing with all sockets
1654 * (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...)
1656 void sock_gen_put(struct sock *sk);
1658 int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested);
1660 static inline void sk_tx_queue_set(struct sock *sk, int tx_queue)
1662 sk->sk_tx_queue_mapping = tx_queue;
1665 static inline void sk_tx_queue_clear(struct sock *sk)
1667 sk->sk_tx_queue_mapping = -1;
1670 static inline int sk_tx_queue_get(const struct sock *sk)
1672 return sk ? sk->sk_tx_queue_mapping : -1;
1675 static inline void sk_set_socket(struct sock *sk, struct socket *sock)
1677 sk_tx_queue_clear(sk);
1678 sk->sk_socket = sock;
1681 static inline wait_queue_head_t *sk_sleep(struct sock *sk)
1683 BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0);
1684 return &rcu_dereference_raw(sk->sk_wq)->wait;
1686 /* Detach socket from process context.
1687 * Announce socket dead, detach it from wait queue and inode.
1688 * Note that parent inode held reference count on this struct sock,
1689 * we do not release it in this function, because protocol
1690 * probably wants some additional cleanups or even continuing
1691 * to work with this socket (TCP).
1693 static inline void sock_orphan(struct sock *sk)
1695 write_lock_bh(&sk->sk_callback_lock);
1696 sock_set_flag(sk, SOCK_DEAD);
1697 sk_set_socket(sk, NULL);
1699 write_unlock_bh(&sk->sk_callback_lock);
1702 static inline void sock_graft(struct sock *sk, struct socket *parent)
1704 write_lock_bh(&sk->sk_callback_lock);
1705 sk->sk_wq = parent->wq;
1707 sk_set_socket(sk, parent);
1708 sk->sk_uid = SOCK_INODE(parent)->i_uid;
1709 security_sock_graft(sk, parent);
1710 write_unlock_bh(&sk->sk_callback_lock);
1713 kuid_t sock_i_uid(struct sock *sk);
1714 unsigned long sock_i_ino(struct sock *sk);
1716 static inline kuid_t sock_net_uid(const struct net *net, const struct sock *sk)
1718 return sk ? sk->sk_uid : make_kuid(net->user_ns, 0);
1721 static inline u32 net_tx_rndhash(void)
1723 u32 v = prandom_u32();
1728 static inline void sk_set_txhash(struct sock *sk)
1730 sk->sk_txhash = net_tx_rndhash();
1733 static inline void sk_rethink_txhash(struct sock *sk)
1739 static inline struct dst_entry *
1740 __sk_dst_get(struct sock *sk)
1742 return rcu_dereference_check(sk->sk_dst_cache, sock_owned_by_user(sk) ||
1743 lockdep_is_held(&sk->sk_lock.slock));
1746 static inline struct dst_entry *
1747 sk_dst_get(struct sock *sk)
1749 struct dst_entry *dst;
1752 dst = rcu_dereference(sk->sk_dst_cache);
1753 if (dst && !atomic_inc_not_zero(&dst->__refcnt))
1759 static inline void dst_negative_advice(struct sock *sk)
1761 struct dst_entry *ndst, *dst = __sk_dst_get(sk);
1763 sk_rethink_txhash(sk);
1765 if (dst && dst->ops->negative_advice) {
1766 ndst = dst->ops->negative_advice(dst);
1769 rcu_assign_pointer(sk->sk_dst_cache, ndst);
1770 sk_tx_queue_clear(sk);
1776 __sk_dst_set(struct sock *sk, struct dst_entry *dst)
1778 struct dst_entry *old_dst;
1780 sk_tx_queue_clear(sk);
1782 * This can be called while sk is owned by the caller only,
1783 * with no state that can be checked in a rcu_dereference_check() cond
1785 old_dst = rcu_dereference_raw(sk->sk_dst_cache);
1786 rcu_assign_pointer(sk->sk_dst_cache, dst);
1787 dst_release(old_dst);
1791 sk_dst_set(struct sock *sk, struct dst_entry *dst)
1793 struct dst_entry *old_dst;
1795 sk_tx_queue_clear(sk);
1796 old_dst = xchg((__force struct dst_entry **)&sk->sk_dst_cache, dst);
1797 dst_release(old_dst);
1801 __sk_dst_reset(struct sock *sk)
1803 __sk_dst_set(sk, NULL);
1807 sk_dst_reset(struct sock *sk)
1809 sk_dst_set(sk, NULL);
1812 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
1814 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
1816 bool sk_mc_loop(struct sock *sk);
1818 static inline bool sk_can_gso(const struct sock *sk)
1820 return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type);
1823 void sk_setup_caps(struct sock *sk, struct dst_entry *dst);
1825 static inline void sk_nocaps_add(struct sock *sk, netdev_features_t flags)
1827 sk->sk_route_nocaps |= flags;
1828 sk->sk_route_caps &= ~flags;
1831 static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
1832 struct iov_iter *from, char *to,
1833 int copy, int offset)
1835 if (skb->ip_summed == CHECKSUM_NONE) {
1837 if (csum_and_copy_from_iter(to, copy, &csum, from) != copy)
1839 skb->csum = csum_block_add(skb->csum, csum, offset);
1840 } else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
1841 if (copy_from_iter_nocache(to, copy, from) != copy)
1843 } else if (copy_from_iter(to, copy, from) != copy)
1849 static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
1850 struct iov_iter *from, int copy)
1852 int err, offset = skb->len;
1854 err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy),
1857 __skb_trim(skb, offset);
1862 static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from,
1863 struct sk_buff *skb,
1869 err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off,
1875 skb->data_len += copy;
1876 skb->truesize += copy;
1877 sk->sk_wmem_queued += copy;
1878 sk_mem_charge(sk, copy);
1883 * sk_wmem_alloc_get - returns write allocations
1886 * Returns sk_wmem_alloc minus initial offset of one
1888 static inline int sk_wmem_alloc_get(const struct sock *sk)
1890 return atomic_read(&sk->sk_wmem_alloc) - 1;
1894 * sk_rmem_alloc_get - returns read allocations
1897 * Returns sk_rmem_alloc
1899 static inline int sk_rmem_alloc_get(const struct sock *sk)
1901 return atomic_read(&sk->sk_rmem_alloc);
1905 * sk_has_allocations - check if allocations are outstanding
1908 * Returns true if socket has write or read allocations
1910 static inline bool sk_has_allocations(const struct sock *sk)
1912 return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk);
1916 * wq_has_sleeper - check if there are any waiting processes
1917 * @wq: struct socket_wq
1919 * Returns true if socket_wq has waiting processes
1921 * The purpose of the wq_has_sleeper and sock_poll_wait is to wrap the memory
1922 * barrier call. They were added due to the race found within the tcp code.
1924 * Consider following tcp code paths:
1928 * sys_select receive packet
1930 * __add_wait_queue update tp->rcv_nxt
1932 * tp->rcv_nxt check sock_def_readable
1934 * schedule rcu_read_lock();
1935 * wq = rcu_dereference(sk->sk_wq);
1936 * if (wq && waitqueue_active(&wq->wait))
1937 * wake_up_interruptible(&wq->wait)
1941 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
1942 * in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1
1943 * could then endup calling schedule and sleep forever if there are no more
1944 * data on the socket.
1947 static inline bool wq_has_sleeper(struct socket_wq *wq)
1949 /* We need to be sure we are in sync with the
1950 * add_wait_queue modifications to the wait queue.
1952 * This memory barrier is paired in the sock_poll_wait.
1955 return wq && waitqueue_active(&wq->wait);
1959 * sock_poll_wait - place memory barrier behind the poll_wait call.
1961 * @wait_address: socket wait queue
1964 * See the comments in the wq_has_sleeper function.
1966 static inline void sock_poll_wait(struct file *filp,
1967 wait_queue_head_t *wait_address, poll_table *p)
1969 if (!poll_does_not_wait(p) && wait_address) {
1970 poll_wait(filp, wait_address, p);
1971 /* We need to be sure we are in sync with the
1972 * socket flags modification.
1974 * This memory barrier is paired in the wq_has_sleeper.
1980 static inline void skb_set_hash_from_sk(struct sk_buff *skb, struct sock *sk)
1982 if (sk->sk_txhash) {
1984 skb->hash = sk->sk_txhash;
1988 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk);
1991 * Queue a received datagram if it will fit. Stream and sequenced
1992 * protocols can't normally use this as they need to fit buffers in
1993 * and play with them.
1995 * Inlined as it's very short and called for pretty much every
1996 * packet ever received.
1998 static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
2002 skb->destructor = sock_rfree;
2003 atomic_add(skb->truesize, &sk->sk_rmem_alloc);
2004 sk_mem_charge(sk, skb->truesize);
2007 void sk_reset_timer(struct sock *sk, struct timer_list *timer,
2008 unsigned long expires);
2010 void sk_stop_timer(struct sock *sk, struct timer_list *timer);
2012 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
2014 int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
2015 struct sk_buff *sock_dequeue_err_skb(struct sock *sk);
2018 * Recover an error report and clear atomically
2021 static inline int sock_error(struct sock *sk)
2024 if (likely(!sk->sk_err))
2026 err = xchg(&sk->sk_err, 0);
2030 static inline unsigned long sock_wspace(struct sock *sk)
2034 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
2035 amt = sk->sk_sndbuf - atomic_read(&sk->sk_wmem_alloc);
2043 * We use sk->sk_wq_raw, from contexts knowing this
2044 * pointer is not NULL and cannot disappear/change.
2046 static inline void sk_set_bit(int nr, struct sock *sk)
2048 set_bit(nr, &sk->sk_wq_raw->flags);
2051 static inline void sk_clear_bit(int nr, struct sock *sk)
2053 clear_bit(nr, &sk->sk_wq_raw->flags);
2056 static inline void sk_wake_async(const struct sock *sk, int how, int band)
2058 if (sock_flag(sk, SOCK_FASYNC)) {
2060 sock_wake_async(rcu_dereference(sk->sk_wq), how, band);
2065 /* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might
2066 * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak.
2067 * Note: for send buffers, TCP works better if we can build two skbs at
2070 #define TCP_SKB_MIN_TRUESIZE (2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff)))
2072 #define SOCK_MIN_SNDBUF (TCP_SKB_MIN_TRUESIZE * 2)
2073 #define SOCK_MIN_RCVBUF TCP_SKB_MIN_TRUESIZE
2075 static inline void sk_stream_moderate_sndbuf(struct sock *sk)
2077 if (!(sk->sk_userlocks & SOCK_SNDBUF_LOCK)) {
2078 sk->sk_sndbuf = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
2079 sk->sk_sndbuf = max_t(u32, sk->sk_sndbuf, SOCK_MIN_SNDBUF);
2083 struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp,
2084 bool force_schedule);
2087 * sk_page_frag - return an appropriate page_frag
2090 * Use the per task page_frag instead of the per socket one for
2091 * optimization when we know that we're in the normal context and owns
2092 * everything that's associated with %current.
2094 * gfpflags_allow_blocking() isn't enough here as direct reclaim may nest
2095 * inside other socket operations and end up recursing into sk_page_frag()
2096 * while it's already in use.
2098 static inline struct page_frag *sk_page_frag(struct sock *sk)
2100 if (gfpflags_normal_context(sk->sk_allocation))
2101 return ¤t->task_frag;
2103 return &sk->sk_frag;
2106 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag);
2109 * Default write policy as shown to user space via poll/select/SIGIO
2111 static inline bool sock_writeable(const struct sock *sk)
2113 return atomic_read(&sk->sk_wmem_alloc) < (sk->sk_sndbuf >> 1);
2116 static inline gfp_t gfp_any(void)
2118 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2121 static inline long sock_rcvtimeo(const struct sock *sk, bool noblock)
2123 return noblock ? 0 : sk->sk_rcvtimeo;
2126 static inline long sock_sndtimeo(const struct sock *sk, bool noblock)
2128 return noblock ? 0 : sk->sk_sndtimeo;
2131 static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
2133 return (waitall ? len : min_t(int, sk->sk_rcvlowat, len)) ? : 1;
2136 /* Alas, with timeout socket operations are not restartable.
2137 * Compare this to poll().
2139 static inline int sock_intr_errno(long timeo)
2141 return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
2144 struct sock_skb_cb {
2148 /* Store sock_skb_cb at the end of skb->cb[] so protocol families
2149 * using skb->cb[] would keep using it directly and utilize its
2150 * alignement guarantee.
2152 #define SOCK_SKB_CB_OFFSET ((FIELD_SIZEOF(struct sk_buff, cb) - \
2153 sizeof(struct sock_skb_cb)))
2155 #define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \
2156 SOCK_SKB_CB_OFFSET))
2158 #define sock_skb_cb_check_size(size) \
2159 BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET)
2162 sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb)
2164 SOCK_SKB_CB(skb)->dropcount = atomic_read(&sk->sk_drops);
2167 static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb)
2169 int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs);
2171 atomic_add(segs, &sk->sk_drops);
2174 static inline ktime_t sock_read_timestamp(struct sock *sk)
2176 #if BITS_PER_LONG==32
2181 seq = read_seqbegin(&sk->sk_stamp_seq);
2183 } while (read_seqretry(&sk->sk_stamp_seq, seq));
2187 return READ_ONCE(sk->sk_stamp);
2191 static inline void sock_write_timestamp(struct sock *sk, ktime_t kt)
2193 #if BITS_PER_LONG==32
2194 write_seqlock(&sk->sk_stamp_seq);
2196 write_sequnlock(&sk->sk_stamp_seq);
2198 WRITE_ONCE(sk->sk_stamp, kt);
2202 void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
2203 struct sk_buff *skb);
2204 void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
2205 struct sk_buff *skb);
2208 sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
2210 ktime_t kt = skb->tstamp;
2211 struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
2214 * generate control messages if
2215 * - receive time stamping in software requested
2216 * - software time stamp available and wanted
2217 * - hardware time stamps available and wanted
2219 if (sock_flag(sk, SOCK_RCVTSTAMP) ||
2220 (sk->sk_tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) ||
2221 (kt.tv64 && sk->sk_tsflags & SOF_TIMESTAMPING_SOFTWARE) ||
2222 (hwtstamps->hwtstamp.tv64 &&
2223 (sk->sk_tsflags & SOF_TIMESTAMPING_RAW_HARDWARE)))
2224 __sock_recv_timestamp(msg, sk, skb);
2226 sock_write_timestamp(sk, kt);
2228 if (sock_flag(sk, SOCK_WIFI_STATUS) && skb->wifi_acked_valid)
2229 __sock_recv_wifi_status(msg, sk, skb);
2232 void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2233 struct sk_buff *skb);
2235 static inline void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2236 struct sk_buff *skb)
2238 #define FLAGS_TS_OR_DROPS ((1UL << SOCK_RXQ_OVFL) | \
2239 (1UL << SOCK_RCVTSTAMP))
2240 #define TSFLAGS_ANY (SOF_TIMESTAMPING_SOFTWARE | \
2241 SOF_TIMESTAMPING_RAW_HARDWARE)
2243 if (sk->sk_flags & FLAGS_TS_OR_DROPS || sk->sk_tsflags & TSFLAGS_ANY)
2244 __sock_recv_ts_and_drops(msg, sk, skb);
2246 sock_write_timestamp(sk, skb->tstamp);
2249 void __sock_tx_timestamp(const struct sock *sk, __u8 *tx_flags);
2252 * sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
2253 * @sk: socket sending this packet
2254 * @tx_flags: completed with instructions for time stamping
2256 * Note : callers should take care of initial *tx_flags value (usually 0)
2258 static inline void sock_tx_timestamp(const struct sock *sk, __u8 *tx_flags)
2260 if (unlikely(sk->sk_tsflags))
2261 __sock_tx_timestamp(sk, tx_flags);
2262 if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS)))
2263 *tx_flags |= SKBTX_WIFI_STATUS;
2267 * sk_eat_skb - Release a skb if it is no longer needed
2268 * @sk: socket to eat this skb from
2269 * @skb: socket buffer to eat
2271 * This routine must be called with interrupts disabled or with the socket
2272 * locked so that the sk_buff queue operation is ok.
2274 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb)
2276 __skb_unlink(skb, &sk->sk_receive_queue);
2281 struct net *sock_net(const struct sock *sk)
2283 return read_pnet(&sk->sk_net);
2287 void sock_net_set(struct sock *sk, struct net *net)
2289 write_pnet(&sk->sk_net, net);
2292 static inline struct sock *skb_steal_sock(struct sk_buff *skb)
2295 struct sock *sk = skb->sk;
2297 skb->destructor = NULL;
2304 /* This helper checks if a socket is a full socket,
2305 * ie _not_ a timewait or request socket.
2307 static inline bool sk_fullsock(const struct sock *sk)
2309 return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV);
2312 /* This helper checks if a socket is a LISTEN or NEW_SYN_RECV
2313 * SYNACK messages can be attached to either ones (depending on SYNCOOKIE)
2315 static inline bool sk_listener(const struct sock *sk)
2317 return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV);
2321 * sk_state_load - read sk->sk_state for lockless contexts
2322 * @sk: socket pointer
2324 * Paired with sk_state_store(). Used in places we do not hold socket lock :
2325 * tcp_diag_get_info(), tcp_get_info(), tcp_poll(), get_tcp4_sock() ...
2327 static inline int sk_state_load(const struct sock *sk)
2329 return smp_load_acquire(&sk->sk_state);
2333 * sk_state_store - update sk->sk_state
2334 * @sk: socket pointer
2335 * @newstate: new state
2337 * Paired with sk_state_load(). Should be used in contexts where
2338 * state change might impact lockless readers.
2340 static inline void sk_state_store(struct sock *sk, int newstate)
2342 smp_store_release(&sk->sk_state, newstate);
2345 void sock_enable_timestamp(struct sock *sk, int flag);
2346 int sock_get_timestamp(struct sock *, struct timeval __user *);
2347 int sock_get_timestampns(struct sock *, struct timespec __user *);
2348 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level,
2351 bool sk_ns_capable(const struct sock *sk,
2352 struct user_namespace *user_ns, int cap);
2353 bool sk_capable(const struct sock *sk, int cap);
2354 bool sk_net_capable(const struct sock *sk, int cap);
2356 extern __u32 sysctl_wmem_max;
2357 extern __u32 sysctl_rmem_max;
2359 extern int sysctl_tstamp_allow_data;
2360 extern int sysctl_optmem_max;
2362 extern __u32 sysctl_wmem_default;
2363 extern __u32 sysctl_rmem_default;
2365 /* SOCKEV Notifier Events */
2366 #define SOCKEV_SOCKET 0x00
2367 #define SOCKEV_BIND 0x01
2368 #define SOCKEV_LISTEN 0x02
2369 #define SOCKEV_ACCEPT 0x03
2370 #define SOCKEV_CONNECT 0x04
2371 #define SOCKEV_SHUTDOWN 0x05
2373 int sockev_register_notify(struct notifier_block *nb);
2374 int sockev_unregister_notify(struct notifier_block *nb);
2376 #endif /* _SOCK_H */