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>
61 #include <linux/wait.h>
62 #include <linux/cgroup-defs.h>
63 #include <linux/rbtree.h>
64 #include <linux/filter.h>
65 #include <linux/rculist_nulls.h>
66 #include <linux/poll.h>
68 #include <linux/atomic.h>
69 #include <linux/refcount.h>
71 #include <net/checksum.h>
72 #include <net/tcp_states.h>
73 #include <linux/net_tstamp.h>
75 #include <net/l3mdev.h>
78 * This structure really needs to be cleaned up.
79 * Most of it is for TCP, and not used by any of
80 * the other protocols.
83 /* Define this to get the SOCK_DBG debugging facility. */
84 #define SOCK_DEBUGGING
86 #define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \
87 printk(KERN_DEBUG msg); } while (0)
89 /* Validate arguments and do nothing */
90 static inline __printf(2, 3)
91 void SOCK_DEBUG(const struct sock *sk, const char *msg, ...)
96 /* This is the per-socket lock. The spinlock provides a synchronization
97 * between user contexts and software interrupt processing, whereas the
98 * mini-semaphore synchronizes multiple users amongst themselves.
103 wait_queue_head_t wq;
105 * We express the mutex-alike socket_lock semantics
106 * to the lock validator by explicitly managing
107 * the slock as a lock variant (in addition to
110 #ifdef CONFIG_DEBUG_LOCK_ALLOC
111 struct lockdep_map dep_map;
119 typedef __u32 __bitwise __portpair;
120 typedef __u64 __bitwise __addrpair;
123 * struct sock_common - minimal network layer representation of sockets
124 * @skc_daddr: Foreign IPv4 addr
125 * @skc_rcv_saddr: Bound local IPv4 addr
126 * @skc_hash: hash value used with various protocol lookup tables
127 * @skc_u16hashes: two u16 hash values used by UDP lookup tables
128 * @skc_dport: placeholder for inet_dport/tw_dport
129 * @skc_num: placeholder for inet_num/tw_num
130 * @skc_family: network address family
131 * @skc_state: Connection state
132 * @skc_reuse: %SO_REUSEADDR setting
133 * @skc_reuseport: %SO_REUSEPORT setting
134 * @skc_bound_dev_if: bound device index if != 0
135 * @skc_bind_node: bind hash linkage for various protocol lookup tables
136 * @skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol
137 * @skc_prot: protocol handlers inside a network family
138 * @skc_net: reference to the network namespace of this socket
139 * @skc_node: main hash linkage for various protocol lookup tables
140 * @skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol
141 * @skc_tx_queue_mapping: tx queue number for this connection
142 * @skc_rx_queue_mapping: rx queue number for this connection
143 * @skc_flags: place holder for sk_flags
144 * %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE,
145 * %SO_OOBINLINE settings, %SO_TIMESTAMPING settings
146 * @skc_incoming_cpu: record/match cpu processing incoming packets
147 * @skc_refcnt: reference count
149 * This is the minimal network layer representation of sockets, the header
150 * for struct sock and struct inet_timewait_sock.
153 /* skc_daddr and skc_rcv_saddr must be grouped on a 8 bytes aligned
154 * address on 64bit arches : cf INET_MATCH()
157 __addrpair skc_addrpair;
160 __be32 skc_rcv_saddr;
164 unsigned int skc_hash;
165 __u16 skc_u16hashes[2];
167 /* skc_dport && skc_num must be grouped as well */
169 __portpair skc_portpair;
176 unsigned short skc_family;
177 volatile unsigned char skc_state;
178 unsigned char skc_reuse:4;
179 unsigned char skc_reuseport:1;
180 unsigned char skc_ipv6only:1;
181 unsigned char skc_net_refcnt:1;
182 int skc_bound_dev_if;
184 struct hlist_node skc_bind_node;
185 struct hlist_node skc_portaddr_node;
187 struct proto *skc_prot;
188 possible_net_t skc_net;
190 #if IS_ENABLED(CONFIG_IPV6)
191 struct in6_addr skc_v6_daddr;
192 struct in6_addr skc_v6_rcv_saddr;
195 atomic64_t skc_cookie;
197 /* following fields are padding to force
198 * offset(struct sock, sk_refcnt) == 128 on 64bit arches
199 * assuming IPV6 is enabled. We use this padding differently
200 * for different kind of 'sockets'
203 unsigned long skc_flags;
204 struct sock *skc_listener; /* request_sock */
205 struct inet_timewait_death_row *skc_tw_dr; /* inet_timewait_sock */
208 * fields between dontcopy_begin/dontcopy_end
209 * are not copied in sock_copy()
212 int skc_dontcopy_begin[0];
215 struct hlist_node skc_node;
216 struct hlist_nulls_node skc_nulls_node;
218 unsigned short skc_tx_queue_mapping;
220 unsigned short skc_rx_queue_mapping;
223 int skc_incoming_cpu;
225 u32 skc_tw_rcv_nxt; /* struct tcp_timewait_sock */
228 refcount_t skc_refcnt;
230 int skc_dontcopy_end[0];
233 u32 skc_window_clamp;
234 u32 skc_tw_snd_nxt; /* struct tcp_timewait_sock */
240 * struct sock - network layer representation of sockets
241 * @__sk_common: shared layout with inet_timewait_sock
242 * @sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
243 * @sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
244 * @sk_lock: synchronizer
245 * @sk_kern_sock: True if sock is using kernel lock classes
246 * @sk_rcvbuf: size of receive buffer in bytes
247 * @sk_wq: sock wait queue and async head
248 * @sk_rx_dst: receive input route used by early demux
249 * @sk_dst_cache: destination cache
250 * @sk_dst_pending_confirm: need to confirm neighbour
251 * @sk_policy: flow policy
252 * @sk_receive_queue: incoming packets
253 * @sk_wmem_alloc: transmit queue bytes committed
254 * @sk_tsq_flags: TCP Small Queues flags
255 * @sk_write_queue: Packet sending queue
256 * @sk_omem_alloc: "o" is "option" or "other"
257 * @sk_wmem_queued: persistent queue size
258 * @sk_forward_alloc: space allocated forward
259 * @sk_napi_id: id of the last napi context to receive data for sk
260 * @sk_ll_usec: usecs to busypoll when there is no data
261 * @sk_allocation: allocation mode
262 * @sk_pacing_rate: Pacing rate (if supported by transport/packet scheduler)
263 * @sk_pacing_status: Pacing status (requested, handled by sch_fq)
264 * @sk_max_pacing_rate: Maximum pacing rate (%SO_MAX_PACING_RATE)
265 * @sk_sndbuf: size of send buffer in bytes
266 * @__sk_flags_offset: empty field used to determine location of bitfield
267 * @sk_padding: unused element for alignment
268 * @sk_no_check_tx: %SO_NO_CHECK setting, set checksum in TX packets
269 * @sk_no_check_rx: allow zero checksum in RX packets
270 * @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
271 * @sk_route_nocaps: forbidden route capabilities (e.g NETIF_F_GSO_MASK)
272 * @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
273 * @sk_gso_max_size: Maximum GSO segment size to build
274 * @sk_gso_max_segs: Maximum number of GSO segments
275 * @sk_pacing_shift: scaling factor for TCP Small Queues
276 * @sk_lingertime: %SO_LINGER l_linger setting
277 * @sk_backlog: always used with the per-socket spinlock held
278 * @sk_callback_lock: used with the callbacks in the end of this struct
279 * @sk_error_queue: rarely used
280 * @sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt,
281 * IPV6_ADDRFORM for instance)
282 * @sk_err: last error
283 * @sk_err_soft: errors that don't cause failure but are the cause of a
284 * persistent failure not just 'timed out'
285 * @sk_drops: raw/udp drops counter
286 * @sk_ack_backlog: current listen backlog
287 * @sk_max_ack_backlog: listen backlog set in listen()
288 * @sk_uid: user id of owner
289 * @sk_priority: %SO_PRIORITY setting
290 * @sk_type: socket type (%SOCK_STREAM, etc)
291 * @sk_protocol: which protocol this socket belongs in this network family
292 * @sk_peer_pid: &struct pid for this socket's peer
293 * @sk_peer_cred: %SO_PEERCRED setting
294 * @sk_rcvlowat: %SO_RCVLOWAT setting
295 * @sk_rcvtimeo: %SO_RCVTIMEO setting
296 * @sk_sndtimeo: %SO_SNDTIMEO setting
297 * @sk_txhash: computed flow hash for use on transmit
298 * @sk_filter: socket filtering instructions
299 * @sk_timer: sock cleanup timer
300 * @sk_stamp: time stamp of last packet received
301 * @sk_stamp_seq: lock for accessing sk_stamp on 32 bit architectures only
302 * @sk_tsflags: SO_TIMESTAMPING socket options
303 * @sk_tskey: counter to disambiguate concurrent tstamp requests
304 * @sk_zckey: counter to order MSG_ZEROCOPY notifications
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_cgrp_data: cgroup data for this cgroup
313 * @sk_memcg: this socket's memory cgroup association
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
321 * @sk_reuseport_cb: reuseport group container
322 * @sk_rcu: used during RCU grace period
323 * @sk_clockid: clockid used by time-based scheduling (SO_TXTIME)
324 * @sk_txtime_deadline_mode: set deadline mode for SO_TXTIME
325 * @sk_txtime_unused: unused txtime flags
329 * Now struct inet_timewait_sock also uses sock_common, so please just
330 * don't add nothing before this first member (__sk_common) --acme
332 struct sock_common __sk_common;
333 #define sk_node __sk_common.skc_node
334 #define sk_nulls_node __sk_common.skc_nulls_node
335 #define sk_refcnt __sk_common.skc_refcnt
336 #define sk_tx_queue_mapping __sk_common.skc_tx_queue_mapping
338 #define sk_rx_queue_mapping __sk_common.skc_rx_queue_mapping
341 #define sk_dontcopy_begin __sk_common.skc_dontcopy_begin
342 #define sk_dontcopy_end __sk_common.skc_dontcopy_end
343 #define sk_hash __sk_common.skc_hash
344 #define sk_portpair __sk_common.skc_portpair
345 #define sk_num __sk_common.skc_num
346 #define sk_dport __sk_common.skc_dport
347 #define sk_addrpair __sk_common.skc_addrpair
348 #define sk_daddr __sk_common.skc_daddr
349 #define sk_rcv_saddr __sk_common.skc_rcv_saddr
350 #define sk_family __sk_common.skc_family
351 #define sk_state __sk_common.skc_state
352 #define sk_reuse __sk_common.skc_reuse
353 #define sk_reuseport __sk_common.skc_reuseport
354 #define sk_ipv6only __sk_common.skc_ipv6only
355 #define sk_net_refcnt __sk_common.skc_net_refcnt
356 #define sk_bound_dev_if __sk_common.skc_bound_dev_if
357 #define sk_bind_node __sk_common.skc_bind_node
358 #define sk_prot __sk_common.skc_prot
359 #define sk_net __sk_common.skc_net
360 #define sk_v6_daddr __sk_common.skc_v6_daddr
361 #define sk_v6_rcv_saddr __sk_common.skc_v6_rcv_saddr
362 #define sk_cookie __sk_common.skc_cookie
363 #define sk_incoming_cpu __sk_common.skc_incoming_cpu
364 #define sk_flags __sk_common.skc_flags
365 #define sk_rxhash __sk_common.skc_rxhash
367 socket_lock_t sk_lock;
370 struct sk_buff_head sk_error_queue;
371 struct sk_buff_head sk_receive_queue;
373 * The backlog queue is special, it is always used with
374 * the per-socket spinlock held and requires low latency
375 * access. Therefore we special case it's implementation.
376 * Note : rmem_alloc is in this structure to fill a hole
377 * on 64bit arches, not because its logically part of
383 struct sk_buff *head;
384 struct sk_buff *tail;
386 #define sk_rmem_alloc sk_backlog.rmem_alloc
388 int sk_forward_alloc;
389 #ifdef CONFIG_NET_RX_BUSY_POLL
390 unsigned int sk_ll_usec;
391 /* ===== mostly read cache line ===== */
392 unsigned int sk_napi_id;
396 struct sk_filter __rcu *sk_filter;
398 struct socket_wq __rcu *sk_wq;
399 struct socket_wq *sk_wq_raw;
402 struct xfrm_policy __rcu *sk_policy[2];
404 struct dst_entry *sk_rx_dst;
405 struct dst_entry __rcu *sk_dst_cache;
406 atomic_t sk_omem_alloc;
409 /* ===== cache line for TX ===== */
411 refcount_t sk_wmem_alloc;
412 unsigned long sk_tsq_flags;
414 struct sk_buff *sk_send_head;
415 struct rb_root tcp_rtx_queue;
417 struct sk_buff_head sk_write_queue;
419 int sk_write_pending;
420 __u32 sk_dst_pending_confirm;
421 u32 sk_pacing_status; /* see enum sk_pacing */
423 struct timer_list sk_timer;
426 u32 sk_pacing_rate; /* bytes per second */
427 u32 sk_max_pacing_rate;
428 struct page_frag sk_frag;
429 netdev_features_t sk_route_caps;
430 netdev_features_t sk_route_nocaps;
431 netdev_features_t sk_route_forced_caps;
433 unsigned int sk_gso_max_size;
438 * Because of non atomicity rules, all
439 * changes are protected by socket lock.
441 unsigned int __sk_flags_offset[0];
442 #ifdef __BIG_ENDIAN_BITFIELD
443 #define SK_FL_PROTO_SHIFT 16
444 #define SK_FL_PROTO_MASK 0x00ff0000
446 #define SK_FL_TYPE_SHIFT 0
447 #define SK_FL_TYPE_MASK 0x0000ffff
449 #define SK_FL_PROTO_SHIFT 8
450 #define SK_FL_PROTO_MASK 0x0000ff00
452 #define SK_FL_TYPE_SHIFT 16
453 #define SK_FL_TYPE_MASK 0xffff0000
456 unsigned int sk_padding : 1,
463 #define SK_PROTOCOL_MAX U8_MAX
466 unsigned long sk_lingertime;
467 struct proto *sk_prot_creator;
468 rwlock_t sk_callback_lock;
472 u32 sk_max_ack_backlog;
474 struct pid *sk_peer_pid;
475 const struct cred *sk_peer_cred;
478 #if BITS_PER_LONG==32
479 seqlock_t sk_stamp_seq;
487 u8 sk_txtime_deadline_mode : 1,
488 sk_txtime_report_errors : 1,
489 sk_txtime_unused : 6;
491 struct socket *sk_socket;
493 #ifdef CONFIG_SECURITY
496 struct sock_cgroup_data sk_cgrp_data;
497 struct mem_cgroup *sk_memcg;
498 void (*sk_state_change)(struct sock *sk);
499 void (*sk_data_ready)(struct sock *sk);
500 void (*sk_write_space)(struct sock *sk);
501 void (*sk_error_report)(struct sock *sk);
502 int (*sk_backlog_rcv)(struct sock *sk,
503 struct sk_buff *skb);
504 #ifdef CONFIG_SOCK_VALIDATE_XMIT
505 struct sk_buff* (*sk_validate_xmit_skb)(struct sock *sk,
506 struct net_device *dev,
507 struct sk_buff *skb);
509 void (*sk_destruct)(struct sock *sk);
510 struct sock_reuseport __rcu *sk_reuseport_cb;
511 struct rcu_head sk_rcu;
516 SK_PACING_NEEDED = 1,
520 #define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data)))
522 #define rcu_dereference_sk_user_data(sk) rcu_dereference(__sk_user_data((sk)))
523 #define rcu_assign_sk_user_data(sk, ptr) rcu_assign_pointer(__sk_user_data((sk)), ptr)
526 * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK
527 * or not whether his port will be reused by someone else. SK_FORCE_REUSE
528 * on a socket means that the socket will reuse everybody else's port
529 * without looking at the other's sk_reuse value.
532 #define SK_NO_REUSE 0
533 #define SK_CAN_REUSE 1
534 #define SK_FORCE_REUSE 2
536 int sk_set_peek_off(struct sock *sk, int val);
538 static inline int sk_peek_offset(struct sock *sk, int flags)
540 if (unlikely(flags & MSG_PEEK)) {
541 return READ_ONCE(sk->sk_peek_off);
547 static inline void sk_peek_offset_bwd(struct sock *sk, int val)
549 s32 off = READ_ONCE(sk->sk_peek_off);
551 if (unlikely(off >= 0)) {
552 off = max_t(s32, off - val, 0);
553 WRITE_ONCE(sk->sk_peek_off, off);
557 static inline void sk_peek_offset_fwd(struct sock *sk, int val)
559 sk_peek_offset_bwd(sk, -val);
563 * Hashed lists helper routines
565 static inline struct sock *sk_entry(const struct hlist_node *node)
567 return hlist_entry(node, struct sock, sk_node);
570 static inline struct sock *__sk_head(const struct hlist_head *head)
572 return hlist_entry(head->first, struct sock, sk_node);
575 static inline struct sock *sk_head(const struct hlist_head *head)
577 return hlist_empty(head) ? NULL : __sk_head(head);
580 static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head)
582 return hlist_nulls_entry(head->first, struct sock, sk_nulls_node);
585 static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head)
587 return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head);
590 static inline struct sock *sk_next(const struct sock *sk)
592 return hlist_entry_safe(sk->sk_node.next, struct sock, sk_node);
595 static inline struct sock *sk_nulls_next(const struct sock *sk)
597 return (!is_a_nulls(sk->sk_nulls_node.next)) ?
598 hlist_nulls_entry(sk->sk_nulls_node.next,
599 struct sock, sk_nulls_node) :
603 static inline bool sk_unhashed(const struct sock *sk)
605 return hlist_unhashed(&sk->sk_node);
608 static inline bool sk_hashed(const struct sock *sk)
610 return !sk_unhashed(sk);
613 static inline void sk_node_init(struct hlist_node *node)
618 static inline void sk_nulls_node_init(struct hlist_nulls_node *node)
623 static inline void __sk_del_node(struct sock *sk)
625 __hlist_del(&sk->sk_node);
628 /* NB: equivalent to hlist_del_init_rcu */
629 static inline bool __sk_del_node_init(struct sock *sk)
633 sk_node_init(&sk->sk_node);
639 /* Grab socket reference count. This operation is valid only
640 when sk is ALREADY grabbed f.e. it is found in hash table
641 or a list and the lookup is made under lock preventing hash table
645 static __always_inline void sock_hold(struct sock *sk)
647 refcount_inc(&sk->sk_refcnt);
650 /* Ungrab socket in the context, which assumes that socket refcnt
651 cannot hit zero, f.e. it is true in context of any socketcall.
653 static __always_inline void __sock_put(struct sock *sk)
655 refcount_dec(&sk->sk_refcnt);
658 static inline bool sk_del_node_init(struct sock *sk)
660 bool rc = __sk_del_node_init(sk);
663 /* paranoid for a while -acme */
664 WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
669 #define sk_del_node_init_rcu(sk) sk_del_node_init(sk)
671 static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk)
674 hlist_nulls_del_init_rcu(&sk->sk_nulls_node);
680 static inline bool sk_nulls_del_node_init_rcu(struct sock *sk)
682 bool rc = __sk_nulls_del_node_init_rcu(sk);
685 /* paranoid for a while -acme */
686 WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
692 static inline void __sk_add_node(struct sock *sk, struct hlist_head *list)
694 hlist_add_head(&sk->sk_node, list);
697 static inline void sk_add_node(struct sock *sk, struct hlist_head *list)
700 __sk_add_node(sk, list);
703 static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list)
706 if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport &&
707 sk->sk_family == AF_INET6)
708 hlist_add_tail_rcu(&sk->sk_node, list);
710 hlist_add_head_rcu(&sk->sk_node, list);
713 static inline void sk_add_node_tail_rcu(struct sock *sk, struct hlist_head *list)
716 hlist_add_tail_rcu(&sk->sk_node, list);
719 static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
721 hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list);
724 static inline void __sk_nulls_add_node_tail_rcu(struct sock *sk, struct hlist_nulls_head *list)
726 hlist_nulls_add_tail_rcu(&sk->sk_nulls_node, list);
729 static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
732 __sk_nulls_add_node_rcu(sk, list);
735 static inline void __sk_del_bind_node(struct sock *sk)
737 __hlist_del(&sk->sk_bind_node);
740 static inline void sk_add_bind_node(struct sock *sk,
741 struct hlist_head *list)
743 hlist_add_head(&sk->sk_bind_node, list);
746 #define sk_for_each(__sk, list) \
747 hlist_for_each_entry(__sk, list, sk_node)
748 #define sk_for_each_rcu(__sk, list) \
749 hlist_for_each_entry_rcu(__sk, list, sk_node)
750 #define sk_nulls_for_each(__sk, node, list) \
751 hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)
752 #define sk_nulls_for_each_rcu(__sk, node, list) \
753 hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)
754 #define sk_for_each_from(__sk) \
755 hlist_for_each_entry_from(__sk, sk_node)
756 #define sk_nulls_for_each_from(__sk, node) \
757 if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \
758 hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node)
759 #define sk_for_each_safe(__sk, tmp, list) \
760 hlist_for_each_entry_safe(__sk, tmp, list, sk_node)
761 #define sk_for_each_bound(__sk, list) \
762 hlist_for_each_entry(__sk, list, sk_bind_node)
765 * sk_for_each_entry_offset_rcu - iterate over a list at a given struct offset
766 * @tpos: the type * to use as a loop cursor.
767 * @pos: the &struct hlist_node to use as a loop cursor.
768 * @head: the head for your list.
769 * @offset: offset of hlist_node within the struct.
772 #define sk_for_each_entry_offset_rcu(tpos, pos, head, offset) \
773 for (pos = rcu_dereference(hlist_first_rcu(head)); \
775 ({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;}); \
776 pos = rcu_dereference(hlist_next_rcu(pos)))
778 static inline struct user_namespace *sk_user_ns(struct sock *sk)
780 /* Careful only use this in a context where these parameters
781 * can not change and must all be valid, such as recvmsg from
784 return sk->sk_socket->file->f_cred->user_ns;
798 SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */
799 SOCK_DBG, /* %SO_DEBUG setting */
800 SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
801 SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */
802 SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
803 SOCK_QUEUE_SHRUNK, /* write queue has been shrunk recently */
804 SOCK_MEMALLOC, /* VM depends on this socket for swapping */
805 SOCK_TIMESTAMPING_RX_SOFTWARE, /* %SOF_TIMESTAMPING_RX_SOFTWARE */
806 SOCK_FASYNC, /* fasync() active */
808 SOCK_ZEROCOPY, /* buffers from userspace */
809 SOCK_WIFI_STATUS, /* push wifi status to userspace */
810 SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS.
811 * Will use last 4 bytes of packet sent from
812 * user-space instead.
814 SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */
815 SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */
816 SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */
820 #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))
822 static inline void sock_copy_flags(struct sock *nsk, struct sock *osk)
824 nsk->sk_flags = osk->sk_flags;
827 static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
829 __set_bit(flag, &sk->sk_flags);
832 static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag)
834 __clear_bit(flag, &sk->sk_flags);
837 static inline bool sock_flag(const struct sock *sk, enum sock_flags flag)
839 return test_bit(flag, &sk->sk_flags);
843 DECLARE_STATIC_KEY_FALSE(memalloc_socks_key);
844 static inline int sk_memalloc_socks(void)
846 return static_branch_unlikely(&memalloc_socks_key);
850 static inline int sk_memalloc_socks(void)
857 static inline gfp_t sk_gfp_mask(const struct sock *sk, gfp_t gfp_mask)
859 return gfp_mask | (sk->sk_allocation & __GFP_MEMALLOC);
862 static inline void sk_acceptq_removed(struct sock *sk)
864 sk->sk_ack_backlog--;
867 static inline void sk_acceptq_added(struct sock *sk)
869 sk->sk_ack_backlog++;
872 static inline bool sk_acceptq_is_full(const struct sock *sk)
874 return sk->sk_ack_backlog > sk->sk_max_ack_backlog;
878 * Compute minimal free write space needed to queue new packets.
880 static inline int sk_stream_min_wspace(const struct sock *sk)
882 return sk->sk_wmem_queued >> 1;
885 static inline int sk_stream_wspace(const struct sock *sk)
887 return sk->sk_sndbuf - sk->sk_wmem_queued;
890 void sk_stream_write_space(struct sock *sk);
892 /* OOB backlog add */
893 static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
895 /* dont let skb dst not refcounted, we are going to leave rcu lock */
898 if (!sk->sk_backlog.tail)
899 sk->sk_backlog.head = skb;
901 sk->sk_backlog.tail->next = skb;
903 sk->sk_backlog.tail = skb;
908 * Take into account size of receive queue and backlog queue
909 * Do not take into account this skb truesize,
910 * to allow even a single big packet to come.
912 static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit)
914 unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc);
916 return qsize > limit;
919 /* The per-socket spinlock must be held here. */
920 static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb,
923 if (sk_rcvqueues_full(sk, limit))
927 * If the skb was allocated from pfmemalloc reserves, only
928 * allow SOCK_MEMALLOC sockets to use it as this socket is
929 * helping free memory
931 if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC))
934 __sk_add_backlog(sk, skb);
935 sk->sk_backlog.len += skb->truesize;
939 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb);
941 static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
943 if (sk_memalloc_socks() && skb_pfmemalloc(skb))
944 return __sk_backlog_rcv(sk, skb);
946 return sk->sk_backlog_rcv(sk, skb);
949 static inline void sk_incoming_cpu_update(struct sock *sk)
951 int cpu = raw_smp_processor_id();
953 if (unlikely(READ_ONCE(sk->sk_incoming_cpu) != cpu))
954 WRITE_ONCE(sk->sk_incoming_cpu, cpu);
957 static inline void sock_rps_record_flow_hash(__u32 hash)
960 struct rps_sock_flow_table *sock_flow_table;
963 sock_flow_table = rcu_dereference(rps_sock_flow_table);
964 rps_record_sock_flow(sock_flow_table, hash);
969 static inline void sock_rps_record_flow(const struct sock *sk)
972 if (static_key_false(&rfs_needed)) {
973 /* Reading sk->sk_rxhash might incur an expensive cache line
976 * TCP_ESTABLISHED does cover almost all states where RFS
977 * might be useful, and is cheaper [1] than testing :
978 * IPv4: inet_sk(sk)->inet_daddr
979 * IPv6: ipv6_addr_any(&sk->sk_v6_daddr)
980 * OR an additional socket flag
981 * [1] : sk_state and sk_prot are in the same cache line.
983 if (sk->sk_state == TCP_ESTABLISHED)
984 sock_rps_record_flow_hash(sk->sk_rxhash);
989 static inline void sock_rps_save_rxhash(struct sock *sk,
990 const struct sk_buff *skb)
993 if (unlikely(sk->sk_rxhash != skb->hash))
994 sk->sk_rxhash = skb->hash;
998 static inline void sock_rps_reset_rxhash(struct sock *sk)
1005 #define sk_wait_event(__sk, __timeo, __condition, __wait) \
1007 release_sock(__sk); \
1008 __rc = __condition; \
1010 *(__timeo) = wait_woken(__wait, \
1011 TASK_INTERRUPTIBLE, \
1014 sched_annotate_sleep(); \
1016 __rc = __condition; \
1020 int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
1021 int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
1022 void sk_stream_wait_close(struct sock *sk, long timeo_p);
1023 int sk_stream_error(struct sock *sk, int flags, int err);
1024 void sk_stream_kill_queues(struct sock *sk);
1025 void sk_set_memalloc(struct sock *sk);
1026 void sk_clear_memalloc(struct sock *sk);
1028 void __sk_flush_backlog(struct sock *sk);
1030 static inline bool sk_flush_backlog(struct sock *sk)
1032 if (unlikely(READ_ONCE(sk->sk_backlog.tail))) {
1033 __sk_flush_backlog(sk);
1039 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb);
1041 struct request_sock_ops;
1042 struct timewait_sock_ops;
1043 struct inet_hashinfo;
1044 struct raw_hashinfo;
1045 struct smc_hashinfo;
1049 * caches using SLAB_TYPESAFE_BY_RCU should let .next pointer from nulls nodes
1050 * un-modified. Special care is taken when initializing object to zero.
1052 static inline void sk_prot_clear_nulls(struct sock *sk, int size)
1054 if (offsetof(struct sock, sk_node.next) != 0)
1055 memset(sk, 0, offsetof(struct sock, sk_node.next));
1056 memset(&sk->sk_node.pprev, 0,
1057 size - offsetof(struct sock, sk_node.pprev));
1060 /* Networking protocol blocks we attach to sockets.
1061 * socket layer -> transport layer interface
1064 void (*close)(struct sock *sk,
1066 int (*pre_connect)(struct sock *sk,
1067 struct sockaddr *uaddr,
1069 int (*connect)(struct sock *sk,
1070 struct sockaddr *uaddr,
1072 int (*disconnect)(struct sock *sk, int flags);
1074 struct sock * (*accept)(struct sock *sk, int flags, int *err,
1077 int (*ioctl)(struct sock *sk, int cmd,
1079 int (*init)(struct sock *sk);
1080 void (*destroy)(struct sock *sk);
1081 void (*shutdown)(struct sock *sk, int how);
1082 int (*setsockopt)(struct sock *sk, int level,
1083 int optname, char __user *optval,
1084 unsigned int optlen);
1085 int (*getsockopt)(struct sock *sk, int level,
1086 int optname, char __user *optval,
1087 int __user *option);
1088 void (*keepalive)(struct sock *sk, int valbool);
1089 #ifdef CONFIG_COMPAT
1090 int (*compat_setsockopt)(struct sock *sk,
1092 int optname, char __user *optval,
1093 unsigned int optlen);
1094 int (*compat_getsockopt)(struct sock *sk,
1096 int optname, char __user *optval,
1097 int __user *option);
1098 int (*compat_ioctl)(struct sock *sk,
1099 unsigned int cmd, unsigned long arg);
1101 int (*sendmsg)(struct sock *sk, struct msghdr *msg,
1103 int (*recvmsg)(struct sock *sk, struct msghdr *msg,
1104 size_t len, int noblock, int flags,
1106 int (*sendpage)(struct sock *sk, struct page *page,
1107 int offset, size_t size, int flags);
1108 int (*bind)(struct sock *sk,
1109 struct sockaddr *uaddr, int addr_len);
1111 int (*backlog_rcv) (struct sock *sk,
1112 struct sk_buff *skb);
1114 void (*release_cb)(struct sock *sk);
1116 /* Keeping track of sk's, looking them up, and port selection methods. */
1117 int (*hash)(struct sock *sk);
1118 void (*unhash)(struct sock *sk);
1119 void (*rehash)(struct sock *sk);
1120 int (*get_port)(struct sock *sk, unsigned short snum);
1122 /* Keeping track of sockets in use */
1123 #ifdef CONFIG_PROC_FS
1124 unsigned int inuse_idx;
1127 bool (*stream_memory_free)(const struct sock *sk);
1128 bool (*stream_memory_read)(const struct sock *sk);
1129 /* Memory pressure */
1130 void (*enter_memory_pressure)(struct sock *sk);
1131 void (*leave_memory_pressure)(struct sock *sk);
1132 atomic_long_t *memory_allocated; /* Current allocated memory. */
1133 struct percpu_counter *sockets_allocated; /* Current number of sockets. */
1135 * Pressure flag: try to collapse.
1136 * Technical note: it is used by multiple contexts non atomically.
1137 * All the __sk_mem_schedule() is of this nature: accounting
1138 * is strict, actions are advisory and have some latency.
1140 unsigned long *memory_pressure;
1145 u32 sysctl_wmem_offset;
1146 u32 sysctl_rmem_offset;
1151 struct kmem_cache *slab;
1152 unsigned int obj_size;
1153 slab_flags_t slab_flags;
1154 unsigned int useroffset; /* Usercopy region offset */
1155 unsigned int usersize; /* Usercopy region size */
1157 struct percpu_counter *orphan_count;
1159 struct request_sock_ops *rsk_prot;
1160 struct timewait_sock_ops *twsk_prot;
1163 struct inet_hashinfo *hashinfo;
1164 struct udp_table *udp_table;
1165 struct raw_hashinfo *raw_hash;
1166 struct smc_hashinfo *smc_hash;
1169 struct module *owner;
1173 struct list_head node;
1174 #ifdef SOCK_REFCNT_DEBUG
1177 int (*diag_destroy)(struct sock *sk, int err);
1178 } __randomize_layout;
1180 int proto_register(struct proto *prot, int alloc_slab);
1181 void proto_unregister(struct proto *prot);
1182 int sock_load_diag_module(int family, int protocol);
1184 #ifdef SOCK_REFCNT_DEBUG
1185 static inline void sk_refcnt_debug_inc(struct sock *sk)
1187 atomic_inc(&sk->sk_prot->socks);
1190 static inline void sk_refcnt_debug_dec(struct sock *sk)
1192 atomic_dec(&sk->sk_prot->socks);
1193 printk(KERN_DEBUG "%s socket %p released, %d are still alive\n",
1194 sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks));
1197 static inline void sk_refcnt_debug_release(const struct sock *sk)
1199 if (refcount_read(&sk->sk_refcnt) != 1)
1200 printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n",
1201 sk->sk_prot->name, sk, refcount_read(&sk->sk_refcnt));
1203 #else /* SOCK_REFCNT_DEBUG */
1204 #define sk_refcnt_debug_inc(sk) do { } while (0)
1205 #define sk_refcnt_debug_dec(sk) do { } while (0)
1206 #define sk_refcnt_debug_release(sk) do { } while (0)
1207 #endif /* SOCK_REFCNT_DEBUG */
1209 static inline bool sk_stream_memory_free(const struct sock *sk)
1211 if (sk->sk_wmem_queued >= sk->sk_sndbuf)
1214 return sk->sk_prot->stream_memory_free ?
1215 sk->sk_prot->stream_memory_free(sk) : true;
1218 static inline bool sk_stream_is_writeable(const struct sock *sk)
1220 return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) &&
1221 sk_stream_memory_free(sk);
1224 static inline int sk_under_cgroup_hierarchy(struct sock *sk,
1225 struct cgroup *ancestor)
1227 #ifdef CONFIG_SOCK_CGROUP_DATA
1228 return cgroup_is_descendant(sock_cgroup_ptr(&sk->sk_cgrp_data),
1235 static inline bool sk_has_memory_pressure(const struct sock *sk)
1237 return sk->sk_prot->memory_pressure != NULL;
1240 static inline bool sk_under_memory_pressure(const struct sock *sk)
1242 if (!sk->sk_prot->memory_pressure)
1245 if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
1246 mem_cgroup_under_socket_pressure(sk->sk_memcg))
1249 return !!*sk->sk_prot->memory_pressure;
1253 sk_memory_allocated(const struct sock *sk)
1255 return atomic_long_read(sk->sk_prot->memory_allocated);
1259 sk_memory_allocated_add(struct sock *sk, int amt)
1261 return atomic_long_add_return(amt, sk->sk_prot->memory_allocated);
1265 sk_memory_allocated_sub(struct sock *sk, int amt)
1267 atomic_long_sub(amt, sk->sk_prot->memory_allocated);
1270 static inline void sk_sockets_allocated_dec(struct sock *sk)
1272 percpu_counter_dec(sk->sk_prot->sockets_allocated);
1275 static inline void sk_sockets_allocated_inc(struct sock *sk)
1277 percpu_counter_inc(sk->sk_prot->sockets_allocated);
1281 sk_sockets_allocated_read_positive(struct sock *sk)
1283 return percpu_counter_read_positive(sk->sk_prot->sockets_allocated);
1287 proto_sockets_allocated_sum_positive(struct proto *prot)
1289 return percpu_counter_sum_positive(prot->sockets_allocated);
1293 proto_memory_allocated(struct proto *prot)
1295 return atomic_long_read(prot->memory_allocated);
1299 proto_memory_pressure(struct proto *prot)
1301 if (!prot->memory_pressure)
1303 return !!*prot->memory_pressure;
1307 #ifdef CONFIG_PROC_FS
1308 /* Called with local bh disabled */
1309 void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc);
1310 int sock_prot_inuse_get(struct net *net, struct proto *proto);
1311 int sock_inuse_get(struct net *net);
1313 static inline void sock_prot_inuse_add(struct net *net, struct proto *prot,
1320 /* With per-bucket locks this operation is not-atomic, so that
1321 * this version is not worse.
1323 static inline int __sk_prot_rehash(struct sock *sk)
1325 sk->sk_prot->unhash(sk);
1326 return sk->sk_prot->hash(sk);
1329 /* About 10 seconds */
1330 #define SOCK_DESTROY_TIME (10*HZ)
1332 /* Sockets 0-1023 can't be bound to unless you are superuser */
1333 #define PROT_SOCK 1024
1335 #define SHUTDOWN_MASK 3
1336 #define RCV_SHUTDOWN 1
1337 #define SEND_SHUTDOWN 2
1339 #define SOCK_SNDBUF_LOCK 1
1340 #define SOCK_RCVBUF_LOCK 2
1341 #define SOCK_BINDADDR_LOCK 4
1342 #define SOCK_BINDPORT_LOCK 8
1344 struct socket_alloc {
1345 struct socket socket;
1346 struct inode vfs_inode;
1349 static inline struct socket *SOCKET_I(struct inode *inode)
1351 return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
1354 static inline struct inode *SOCK_INODE(struct socket *socket)
1356 return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
1360 * Functions for memory accounting
1362 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind);
1363 int __sk_mem_schedule(struct sock *sk, int size, int kind);
1364 void __sk_mem_reduce_allocated(struct sock *sk, int amount);
1365 void __sk_mem_reclaim(struct sock *sk, int amount);
1367 /* We used to have PAGE_SIZE here, but systems with 64KB pages
1368 * do not necessarily have 16x time more memory than 4KB ones.
1370 #define SK_MEM_QUANTUM 4096
1371 #define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM)
1372 #define SK_MEM_SEND 0
1373 #define SK_MEM_RECV 1
1375 /* sysctl_mem values are in pages, we convert them in SK_MEM_QUANTUM units */
1376 static inline long sk_prot_mem_limits(const struct sock *sk, int index)
1378 long val = sk->sk_prot->sysctl_mem[index];
1380 #if PAGE_SIZE > SK_MEM_QUANTUM
1381 val <<= PAGE_SHIFT - SK_MEM_QUANTUM_SHIFT;
1382 #elif PAGE_SIZE < SK_MEM_QUANTUM
1383 val >>= SK_MEM_QUANTUM_SHIFT - PAGE_SHIFT;
1388 static inline int sk_mem_pages(int amt)
1390 return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT;
1393 static inline bool sk_has_account(struct sock *sk)
1395 /* return true if protocol supports memory accounting */
1396 return !!sk->sk_prot->memory_allocated;
1399 static inline bool sk_wmem_schedule(struct sock *sk, int size)
1401 if (!sk_has_account(sk))
1403 return size <= sk->sk_forward_alloc ||
1404 __sk_mem_schedule(sk, size, SK_MEM_SEND);
1408 sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size)
1410 if (!sk_has_account(sk))
1412 return size<= sk->sk_forward_alloc ||
1413 __sk_mem_schedule(sk, size, SK_MEM_RECV) ||
1414 skb_pfmemalloc(skb);
1417 static inline void sk_mem_reclaim(struct sock *sk)
1419 if (!sk_has_account(sk))
1421 if (sk->sk_forward_alloc >= SK_MEM_QUANTUM)
1422 __sk_mem_reclaim(sk, sk->sk_forward_alloc);
1425 static inline void sk_mem_reclaim_partial(struct sock *sk)
1427 if (!sk_has_account(sk))
1429 if (sk->sk_forward_alloc > SK_MEM_QUANTUM)
1430 __sk_mem_reclaim(sk, sk->sk_forward_alloc - 1);
1433 static inline void sk_mem_charge(struct sock *sk, int size)
1435 if (!sk_has_account(sk))
1437 sk->sk_forward_alloc -= size;
1440 static inline void sk_mem_uncharge(struct sock *sk, int size)
1442 if (!sk_has_account(sk))
1444 sk->sk_forward_alloc += size;
1446 /* Avoid a possible overflow.
1447 * TCP send queues can make this happen, if sk_mem_reclaim()
1448 * is not called and more than 2 GBytes are released at once.
1450 * If we reach 2 MBytes, reclaim 1 MBytes right now, there is
1451 * no need to hold that much forward allocation anyway.
1453 if (unlikely(sk->sk_forward_alloc >= 1 << 21))
1454 __sk_mem_reclaim(sk, 1 << 20);
1457 static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb)
1459 sock_set_flag(sk, SOCK_QUEUE_SHRUNK);
1460 sk->sk_wmem_queued -= skb->truesize;
1461 sk_mem_uncharge(sk, skb->truesize);
1465 static inline void sock_release_ownership(struct sock *sk)
1467 if (sk->sk_lock.owned) {
1468 sk->sk_lock.owned = 0;
1470 /* The sk_lock has mutex_unlock() semantics: */
1471 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
1476 * Macro so as to not evaluate some arguments when
1477 * lockdep is not enabled.
1479 * Mark both the sk_lock and the sk_lock.slock as a
1480 * per-address-family lock class.
1482 #define sock_lock_init_class_and_name(sk, sname, skey, name, key) \
1484 sk->sk_lock.owned = 0; \
1485 init_waitqueue_head(&sk->sk_lock.wq); \
1486 spin_lock_init(&(sk)->sk_lock.slock); \
1487 debug_check_no_locks_freed((void *)&(sk)->sk_lock, \
1488 sizeof((sk)->sk_lock)); \
1489 lockdep_set_class_and_name(&(sk)->sk_lock.slock, \
1491 lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \
1494 #ifdef CONFIG_LOCKDEP
1495 static inline bool lockdep_sock_is_held(const struct sock *sk)
1497 return lockdep_is_held(&sk->sk_lock) ||
1498 lockdep_is_held(&sk->sk_lock.slock);
1502 void lock_sock_nested(struct sock *sk, int subclass);
1504 static inline void lock_sock(struct sock *sk)
1506 lock_sock_nested(sk, 0);
1509 void __release_sock(struct sock *sk);
1510 void release_sock(struct sock *sk);
1512 /* BH context may only use the following locking interface. */
1513 #define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock))
1514 #define bh_lock_sock_nested(__sk) \
1515 spin_lock_nested(&((__sk)->sk_lock.slock), \
1516 SINGLE_DEPTH_NESTING)
1517 #define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock))
1519 bool lock_sock_fast(struct sock *sk);
1521 * unlock_sock_fast - complement of lock_sock_fast
1525 * fast unlock socket for user context.
1526 * If slow mode is on, we call regular release_sock()
1528 static inline void unlock_sock_fast(struct sock *sk, bool slow)
1533 spin_unlock_bh(&sk->sk_lock.slock);
1536 /* Used by processes to "lock" a socket state, so that
1537 * interrupts and bottom half handlers won't change it
1538 * from under us. It essentially blocks any incoming
1539 * packets, so that we won't get any new data or any
1540 * packets that change the state of the socket.
1542 * While locked, BH processing will add new packets to
1543 * the backlog queue. This queue is processed by the
1544 * owner of the socket lock right before it is released.
1546 * Since ~2.3.5 it is also exclusive sleep lock serializing
1547 * accesses from user process context.
1550 static inline void sock_owned_by_me(const struct sock *sk)
1552 #ifdef CONFIG_LOCKDEP
1553 WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks);
1557 static inline bool sock_owned_by_user(const struct sock *sk)
1559 sock_owned_by_me(sk);
1560 return sk->sk_lock.owned;
1563 static inline bool sock_owned_by_user_nocheck(const struct sock *sk)
1565 return sk->sk_lock.owned;
1568 /* no reclassification while locks are held */
1569 static inline bool sock_allow_reclassification(const struct sock *csk)
1571 struct sock *sk = (struct sock *)csk;
1573 return !sk->sk_lock.owned && !spin_is_locked(&sk->sk_lock.slock);
1576 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1577 struct proto *prot, int kern);
1578 void sk_free(struct sock *sk);
1579 void sk_destruct(struct sock *sk);
1580 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority);
1581 void sk_free_unlock_clone(struct sock *sk);
1583 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1585 void __sock_wfree(struct sk_buff *skb);
1586 void sock_wfree(struct sk_buff *skb);
1587 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
1589 void skb_orphan_partial(struct sk_buff *skb);
1590 void sock_rfree(struct sk_buff *skb);
1591 void sock_efree(struct sk_buff *skb);
1593 void sock_edemux(struct sk_buff *skb);
1595 #define sock_edemux sock_efree
1598 int sock_setsockopt(struct socket *sock, int level, int op,
1599 char __user *optval, unsigned int optlen);
1601 int sock_getsockopt(struct socket *sock, int level, int op,
1602 char __user *optval, int __user *optlen);
1603 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1604 int noblock, int *errcode);
1605 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1606 unsigned long data_len, int noblock,
1607 int *errcode, int max_page_order);
1608 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority);
1609 void sock_kfree_s(struct sock *sk, void *mem, int size);
1610 void sock_kzfree_s(struct sock *sk, void *mem, int size);
1611 void sk_send_sigurg(struct sock *sk);
1613 struct sockcm_cookie {
1619 static inline void sockcm_init(struct sockcm_cookie *sockc,
1620 const struct sock *sk)
1622 *sockc = (struct sockcm_cookie) { .tsflags = sk->sk_tsflags };
1625 int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg,
1626 struct sockcm_cookie *sockc);
1627 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
1628 struct sockcm_cookie *sockc);
1631 * Functions to fill in entries in struct proto_ops when a protocol
1632 * does not implement a particular function.
1634 int sock_no_bind(struct socket *, struct sockaddr *, int);
1635 int sock_no_connect(struct socket *, struct sockaddr *, int, int);
1636 int sock_no_socketpair(struct socket *, struct socket *);
1637 int sock_no_accept(struct socket *, struct socket *, int, bool);
1638 int sock_no_getname(struct socket *, struct sockaddr *, int);
1639 int sock_no_ioctl(struct socket *, unsigned int, unsigned long);
1640 int sock_no_listen(struct socket *, int);
1641 int sock_no_shutdown(struct socket *, int);
1642 int sock_no_getsockopt(struct socket *, int , int, char __user *, int __user *);
1643 int sock_no_setsockopt(struct socket *, int, int, char __user *, unsigned int);
1644 int sock_no_sendmsg(struct socket *, struct msghdr *, size_t);
1645 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len);
1646 int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int);
1647 int sock_no_mmap(struct file *file, struct socket *sock,
1648 struct vm_area_struct *vma);
1649 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset,
1650 size_t size, int flags);
1651 ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
1652 int offset, size_t size, int flags);
1655 * Functions to fill in entries in struct proto_ops when a protocol
1656 * uses the inet style.
1658 int sock_common_getsockopt(struct socket *sock, int level, int optname,
1659 char __user *optval, int __user *optlen);
1660 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1662 int sock_common_setsockopt(struct socket *sock, int level, int optname,
1663 char __user *optval, unsigned int optlen);
1664 int compat_sock_common_getsockopt(struct socket *sock, int level,
1665 int optname, char __user *optval, int __user *optlen);
1666 int compat_sock_common_setsockopt(struct socket *sock, int level,
1667 int optname, char __user *optval, unsigned int optlen);
1669 void sk_common_release(struct sock *sk);
1672 * Default socket callbacks and setup code
1675 /* Initialise core socket variables */
1676 void sock_init_data(struct socket *sock, struct sock *sk);
1679 * Socket reference counting postulates.
1681 * * Each user of socket SHOULD hold a reference count.
1682 * * Each access point to socket (an hash table bucket, reference from a list,
1683 * running timer, skb in flight MUST hold a reference count.
1684 * * When reference count hits 0, it means it will never increase back.
1685 * * When reference count hits 0, it means that no references from
1686 * outside exist to this socket and current process on current CPU
1687 * is last user and may/should destroy this socket.
1688 * * sk_free is called from any context: process, BH, IRQ. When
1689 * it is called, socket has no references from outside -> sk_free
1690 * may release descendant resources allocated by the socket, but
1691 * to the time when it is called, socket is NOT referenced by any
1692 * hash tables, lists etc.
1693 * * Packets, delivered from outside (from network or from another process)
1694 * and enqueued on receive/error queues SHOULD NOT grab reference count,
1695 * when they sit in queue. Otherwise, packets will leak to hole, when
1696 * socket is looked up by one cpu and unhasing is made by another CPU.
1697 * It is true for udp/raw, netlink (leak to receive and error queues), tcp
1698 * (leak to backlog). Packet socket does all the processing inside
1699 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
1700 * use separate SMP lock, so that they are prone too.
1703 /* Ungrab socket and destroy it, if it was the last reference. */
1704 static inline void sock_put(struct sock *sk)
1706 if (refcount_dec_and_test(&sk->sk_refcnt))
1709 /* Generic version of sock_put(), dealing with all sockets
1710 * (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...)
1712 void sock_gen_put(struct sock *sk);
1714 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested,
1715 unsigned int trim_cap, bool refcounted);
1716 static inline int sk_receive_skb(struct sock *sk, struct sk_buff *skb,
1719 return __sk_receive_skb(sk, skb, nested, 1, true);
1722 static inline void sk_tx_queue_set(struct sock *sk, int tx_queue)
1724 /* sk_tx_queue_mapping accept only upto a 16-bit value */
1725 if (WARN_ON_ONCE((unsigned short)tx_queue >= USHRT_MAX))
1727 sk->sk_tx_queue_mapping = tx_queue;
1730 #define NO_QUEUE_MAPPING USHRT_MAX
1732 static inline void sk_tx_queue_clear(struct sock *sk)
1734 sk->sk_tx_queue_mapping = NO_QUEUE_MAPPING;
1737 static inline int sk_tx_queue_get(const struct sock *sk)
1739 if (sk && sk->sk_tx_queue_mapping != NO_QUEUE_MAPPING)
1740 return sk->sk_tx_queue_mapping;
1745 static inline void sk_rx_queue_set(struct sock *sk, const struct sk_buff *skb)
1748 if (skb_rx_queue_recorded(skb)) {
1749 u16 rx_queue = skb_get_rx_queue(skb);
1751 if (WARN_ON_ONCE(rx_queue == NO_QUEUE_MAPPING))
1754 sk->sk_rx_queue_mapping = rx_queue;
1759 static inline void sk_rx_queue_clear(struct sock *sk)
1762 sk->sk_rx_queue_mapping = NO_QUEUE_MAPPING;
1767 static inline int sk_rx_queue_get(const struct sock *sk)
1769 if (sk && sk->sk_rx_queue_mapping != NO_QUEUE_MAPPING)
1770 return sk->sk_rx_queue_mapping;
1776 static inline void sk_set_socket(struct sock *sk, struct socket *sock)
1778 sk_tx_queue_clear(sk);
1779 sk->sk_socket = sock;
1782 static inline wait_queue_head_t *sk_sleep(struct sock *sk)
1784 BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0);
1785 return &rcu_dereference_raw(sk->sk_wq)->wait;
1787 /* Detach socket from process context.
1788 * Announce socket dead, detach it from wait queue and inode.
1789 * Note that parent inode held reference count on this struct sock,
1790 * we do not release it in this function, because protocol
1791 * probably wants some additional cleanups or even continuing
1792 * to work with this socket (TCP).
1794 static inline void sock_orphan(struct sock *sk)
1796 write_lock_bh(&sk->sk_callback_lock);
1797 sock_set_flag(sk, SOCK_DEAD);
1798 sk_set_socket(sk, NULL);
1800 write_unlock_bh(&sk->sk_callback_lock);
1803 static inline void sock_graft(struct sock *sk, struct socket *parent)
1805 WARN_ON(parent->sk);
1806 write_lock_bh(&sk->sk_callback_lock);
1807 rcu_assign_pointer(sk->sk_wq, parent->wq);
1809 sk_set_socket(sk, parent);
1810 sk->sk_uid = SOCK_INODE(parent)->i_uid;
1811 security_sock_graft(sk, parent);
1812 write_unlock_bh(&sk->sk_callback_lock);
1815 kuid_t sock_i_uid(struct sock *sk);
1816 unsigned long sock_i_ino(struct sock *sk);
1818 static inline kuid_t sock_net_uid(const struct net *net, const struct sock *sk)
1820 return sk ? sk->sk_uid : make_kuid(net->user_ns, 0);
1823 static inline u32 net_tx_rndhash(void)
1825 u32 v = prandom_u32();
1830 static inline void sk_set_txhash(struct sock *sk)
1832 sk->sk_txhash = net_tx_rndhash();
1835 static inline void sk_rethink_txhash(struct sock *sk)
1841 static inline struct dst_entry *
1842 __sk_dst_get(struct sock *sk)
1844 return rcu_dereference_check(sk->sk_dst_cache,
1845 lockdep_sock_is_held(sk));
1848 static inline struct dst_entry *
1849 sk_dst_get(struct sock *sk)
1851 struct dst_entry *dst;
1854 dst = rcu_dereference(sk->sk_dst_cache);
1855 if (dst && !atomic_inc_not_zero(&dst->__refcnt))
1861 static inline void dst_negative_advice(struct sock *sk)
1863 struct dst_entry *ndst, *dst = __sk_dst_get(sk);
1865 sk_rethink_txhash(sk);
1867 if (dst && dst->ops->negative_advice) {
1868 ndst = dst->ops->negative_advice(dst);
1871 rcu_assign_pointer(sk->sk_dst_cache, ndst);
1872 sk_tx_queue_clear(sk);
1873 sk->sk_dst_pending_confirm = 0;
1879 __sk_dst_set(struct sock *sk, struct dst_entry *dst)
1881 struct dst_entry *old_dst;
1883 sk_tx_queue_clear(sk);
1884 sk->sk_dst_pending_confirm = 0;
1885 old_dst = rcu_dereference_protected(sk->sk_dst_cache,
1886 lockdep_sock_is_held(sk));
1887 rcu_assign_pointer(sk->sk_dst_cache, dst);
1888 dst_release(old_dst);
1892 sk_dst_set(struct sock *sk, struct dst_entry *dst)
1894 struct dst_entry *old_dst;
1896 sk_tx_queue_clear(sk);
1897 sk->sk_dst_pending_confirm = 0;
1898 old_dst = xchg((__force struct dst_entry **)&sk->sk_dst_cache, dst);
1899 dst_release(old_dst);
1903 __sk_dst_reset(struct sock *sk)
1905 __sk_dst_set(sk, NULL);
1909 sk_dst_reset(struct sock *sk)
1911 sk_dst_set(sk, NULL);
1914 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
1916 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
1918 static inline void sk_dst_confirm(struct sock *sk)
1920 if (!sk->sk_dst_pending_confirm)
1921 sk->sk_dst_pending_confirm = 1;
1924 static inline void sock_confirm_neigh(struct sk_buff *skb, struct neighbour *n)
1926 if (skb_get_dst_pending_confirm(skb)) {
1927 struct sock *sk = skb->sk;
1928 unsigned long now = jiffies;
1930 /* avoid dirtying neighbour */
1931 if (n->confirmed != now)
1933 if (sk && sk->sk_dst_pending_confirm)
1934 sk->sk_dst_pending_confirm = 0;
1938 bool sk_mc_loop(struct sock *sk);
1940 static inline bool sk_can_gso(const struct sock *sk)
1942 return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type);
1945 void sk_setup_caps(struct sock *sk, struct dst_entry *dst);
1947 static inline void sk_nocaps_add(struct sock *sk, netdev_features_t flags)
1949 sk->sk_route_nocaps |= flags;
1950 sk->sk_route_caps &= ~flags;
1953 static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
1954 struct iov_iter *from, char *to,
1955 int copy, int offset)
1957 if (skb->ip_summed == CHECKSUM_NONE) {
1959 if (!csum_and_copy_from_iter_full(to, copy, &csum, from))
1961 skb->csum = csum_block_add(skb->csum, csum, offset);
1962 } else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
1963 if (!copy_from_iter_full_nocache(to, copy, from))
1965 } else if (!copy_from_iter_full(to, copy, from))
1971 static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
1972 struct iov_iter *from, int copy)
1974 int err, offset = skb->len;
1976 err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy),
1979 __skb_trim(skb, offset);
1984 static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from,
1985 struct sk_buff *skb,
1991 err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off,
1997 skb->data_len += copy;
1998 skb->truesize += copy;
1999 sk->sk_wmem_queued += copy;
2000 sk_mem_charge(sk, copy);
2005 * sk_wmem_alloc_get - returns write allocations
2008 * Returns sk_wmem_alloc minus initial offset of one
2010 static inline int sk_wmem_alloc_get(const struct sock *sk)
2012 return refcount_read(&sk->sk_wmem_alloc) - 1;
2016 * sk_rmem_alloc_get - returns read allocations
2019 * Returns sk_rmem_alloc
2021 static inline int sk_rmem_alloc_get(const struct sock *sk)
2023 return atomic_read(&sk->sk_rmem_alloc);
2027 * sk_has_allocations - check if allocations are outstanding
2030 * Returns true if socket has write or read allocations
2032 static inline bool sk_has_allocations(const struct sock *sk)
2034 return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk);
2038 * skwq_has_sleeper - check if there are any waiting processes
2039 * @wq: struct socket_wq
2041 * Returns true if socket_wq has waiting processes
2043 * The purpose of the skwq_has_sleeper and sock_poll_wait is to wrap the memory
2044 * barrier call. They were added due to the race found within the tcp code.
2046 * Consider following tcp code paths::
2049 * sys_select receive packet
2051 * __add_wait_queue update tp->rcv_nxt
2053 * tp->rcv_nxt check sock_def_readable
2055 * schedule rcu_read_lock();
2056 * wq = rcu_dereference(sk->sk_wq);
2057 * if (wq && waitqueue_active(&wq->wait))
2058 * wake_up_interruptible(&wq->wait)
2062 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
2063 * in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1
2064 * could then endup calling schedule and sleep forever if there are no more
2065 * data on the socket.
2068 static inline bool skwq_has_sleeper(struct socket_wq *wq)
2070 return wq && wq_has_sleeper(&wq->wait);
2074 * sock_poll_wait - place memory barrier behind the poll_wait call.
2076 * @sock: socket to wait on
2079 * See the comments in the wq_has_sleeper function.
2081 * Do not derive sock from filp->private_data here. An SMC socket establishes
2082 * an internal TCP socket that is used in the fallback case. All socket
2083 * operations on the SMC socket are then forwarded to the TCP socket. In case of
2084 * poll, the filp->private_data pointer references the SMC socket because the
2085 * TCP socket has no file assigned.
2087 static inline void sock_poll_wait(struct file *filp, struct socket *sock,
2090 if (!poll_does_not_wait(p)) {
2091 poll_wait(filp, &sock->wq->wait, p);
2092 /* We need to be sure we are in sync with the
2093 * socket flags modification.
2095 * This memory barrier is paired in the wq_has_sleeper.
2101 static inline void skb_set_hash_from_sk(struct sk_buff *skb, struct sock *sk)
2103 if (sk->sk_txhash) {
2105 skb->hash = sk->sk_txhash;
2109 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk);
2112 * Queue a received datagram if it will fit. Stream and sequenced
2113 * protocols can't normally use this as they need to fit buffers in
2114 * and play with them.
2116 * Inlined as it's very short and called for pretty much every
2117 * packet ever received.
2119 static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
2123 skb->destructor = sock_rfree;
2124 atomic_add(skb->truesize, &sk->sk_rmem_alloc);
2125 sk_mem_charge(sk, skb->truesize);
2128 void sk_reset_timer(struct sock *sk, struct timer_list *timer,
2129 unsigned long expires);
2131 void sk_stop_timer(struct sock *sk, struct timer_list *timer);
2133 int __sk_queue_drop_skb(struct sock *sk, struct sk_buff_head *sk_queue,
2134 struct sk_buff *skb, unsigned int flags,
2135 void (*destructor)(struct sock *sk,
2136 struct sk_buff *skb));
2137 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
2138 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
2140 int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
2141 struct sk_buff *sock_dequeue_err_skb(struct sock *sk);
2144 * Recover an error report and clear atomically
2147 static inline int sock_error(struct sock *sk)
2150 if (likely(!sk->sk_err))
2152 err = xchg(&sk->sk_err, 0);
2156 static inline unsigned long sock_wspace(struct sock *sk)
2160 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
2161 amt = sk->sk_sndbuf - refcount_read(&sk->sk_wmem_alloc);
2169 * We use sk->sk_wq_raw, from contexts knowing this
2170 * pointer is not NULL and cannot disappear/change.
2172 static inline void sk_set_bit(int nr, struct sock *sk)
2174 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2175 !sock_flag(sk, SOCK_FASYNC))
2178 set_bit(nr, &sk->sk_wq_raw->flags);
2181 static inline void sk_clear_bit(int nr, struct sock *sk)
2183 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2184 !sock_flag(sk, SOCK_FASYNC))
2187 clear_bit(nr, &sk->sk_wq_raw->flags);
2190 static inline void sk_wake_async(const struct sock *sk, int how, int band)
2192 if (sock_flag(sk, SOCK_FASYNC)) {
2194 sock_wake_async(rcu_dereference(sk->sk_wq), how, band);
2199 /* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might
2200 * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak.
2201 * Note: for send buffers, TCP works better if we can build two skbs at
2204 #define TCP_SKB_MIN_TRUESIZE (2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff)))
2206 #define SOCK_MIN_SNDBUF (TCP_SKB_MIN_TRUESIZE * 2)
2207 #define SOCK_MIN_RCVBUF TCP_SKB_MIN_TRUESIZE
2209 static inline void sk_stream_moderate_sndbuf(struct sock *sk)
2211 if (!(sk->sk_userlocks & SOCK_SNDBUF_LOCK)) {
2212 sk->sk_sndbuf = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
2213 sk->sk_sndbuf = max_t(u32, sk->sk_sndbuf, SOCK_MIN_SNDBUF);
2217 struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp,
2218 bool force_schedule);
2221 * sk_page_frag - return an appropriate page_frag
2224 * Use the per task page_frag instead of the per socket one for
2225 * optimization when we know that we're in the normal context and owns
2226 * everything that's associated with %current.
2228 * gfpflags_allow_blocking() isn't enough here as direct reclaim may nest
2229 * inside other socket operations and end up recursing into sk_page_frag()
2230 * while it's already in use.
2232 static inline struct page_frag *sk_page_frag(struct sock *sk)
2234 if (gfpflags_normal_context(sk->sk_allocation))
2235 return ¤t->task_frag;
2237 return &sk->sk_frag;
2240 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag);
2242 int sk_alloc_sg(struct sock *sk, int len, struct scatterlist *sg,
2243 int sg_start, int *sg_curr, unsigned int *sg_size,
2244 int first_coalesce);
2247 * Default write policy as shown to user space via poll/select/SIGIO
2249 static inline bool sock_writeable(const struct sock *sk)
2251 return refcount_read(&sk->sk_wmem_alloc) < (sk->sk_sndbuf >> 1);
2254 static inline gfp_t gfp_any(void)
2256 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2259 static inline long sock_rcvtimeo(const struct sock *sk, bool noblock)
2261 return noblock ? 0 : sk->sk_rcvtimeo;
2264 static inline long sock_sndtimeo(const struct sock *sk, bool noblock)
2266 return noblock ? 0 : sk->sk_sndtimeo;
2269 static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
2271 return (waitall ? len : min_t(int, sk->sk_rcvlowat, len)) ? : 1;
2274 /* Alas, with timeout socket operations are not restartable.
2275 * Compare this to poll().
2277 static inline int sock_intr_errno(long timeo)
2279 return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
2282 struct sock_skb_cb {
2286 /* Store sock_skb_cb at the end of skb->cb[] so protocol families
2287 * using skb->cb[] would keep using it directly and utilize its
2288 * alignement guarantee.
2290 #define SOCK_SKB_CB_OFFSET ((FIELD_SIZEOF(struct sk_buff, cb) - \
2291 sizeof(struct sock_skb_cb)))
2293 #define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \
2294 SOCK_SKB_CB_OFFSET))
2296 #define sock_skb_cb_check_size(size) \
2297 BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET)
2300 sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb)
2302 SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, SOCK_RXQ_OVFL) ?
2303 atomic_read(&sk->sk_drops) : 0;
2306 static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb)
2308 int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs);
2310 atomic_add(segs, &sk->sk_drops);
2313 static inline ktime_t sock_read_timestamp(struct sock *sk)
2315 #if BITS_PER_LONG==32
2320 seq = read_seqbegin(&sk->sk_stamp_seq);
2322 } while (read_seqretry(&sk->sk_stamp_seq, seq));
2326 return READ_ONCE(sk->sk_stamp);
2330 static inline void sock_write_timestamp(struct sock *sk, ktime_t kt)
2332 #if BITS_PER_LONG==32
2333 write_seqlock(&sk->sk_stamp_seq);
2335 write_sequnlock(&sk->sk_stamp_seq);
2337 WRITE_ONCE(sk->sk_stamp, kt);
2341 void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
2342 struct sk_buff *skb);
2343 void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
2344 struct sk_buff *skb);
2347 sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
2349 ktime_t kt = skb->tstamp;
2350 struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
2353 * generate control messages if
2354 * - receive time stamping in software requested
2355 * - software time stamp available and wanted
2356 * - hardware time stamps available and wanted
2358 if (sock_flag(sk, SOCK_RCVTSTAMP) ||
2359 (sk->sk_tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) ||
2360 (kt && sk->sk_tsflags & SOF_TIMESTAMPING_SOFTWARE) ||
2361 (hwtstamps->hwtstamp &&
2362 (sk->sk_tsflags & SOF_TIMESTAMPING_RAW_HARDWARE)))
2363 __sock_recv_timestamp(msg, sk, skb);
2365 sock_write_timestamp(sk, kt);
2367 if (sock_flag(sk, SOCK_WIFI_STATUS) && skb->wifi_acked_valid)
2368 __sock_recv_wifi_status(msg, sk, skb);
2371 void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2372 struct sk_buff *skb);
2374 #define SK_DEFAULT_STAMP (-1L * NSEC_PER_SEC)
2375 static inline void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2376 struct sk_buff *skb)
2378 #define FLAGS_TS_OR_DROPS ((1UL << SOCK_RXQ_OVFL) | \
2379 (1UL << SOCK_RCVTSTAMP))
2380 #define TSFLAGS_ANY (SOF_TIMESTAMPING_SOFTWARE | \
2381 SOF_TIMESTAMPING_RAW_HARDWARE)
2383 if (sk->sk_flags & FLAGS_TS_OR_DROPS || sk->sk_tsflags & TSFLAGS_ANY)
2384 __sock_recv_ts_and_drops(msg, sk, skb);
2385 else if (unlikely(sock_flag(sk, SOCK_TIMESTAMP)))
2386 sock_write_timestamp(sk, skb->tstamp);
2387 else if (unlikely(sk->sk_stamp == SK_DEFAULT_STAMP))
2388 sock_write_timestamp(sk, 0);
2391 void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags);
2394 * sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
2395 * @sk: socket sending this packet
2396 * @tsflags: timestamping flags to use
2397 * @tx_flags: completed with instructions for time stamping
2399 * Note: callers should take care of initial ``*tx_flags`` value (usually 0)
2401 static inline void sock_tx_timestamp(const struct sock *sk, __u16 tsflags,
2404 if (unlikely(tsflags))
2405 __sock_tx_timestamp(tsflags, tx_flags);
2406 if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS)))
2407 *tx_flags |= SKBTX_WIFI_STATUS;
2411 * sk_eat_skb - Release a skb if it is no longer needed
2412 * @sk: socket to eat this skb from
2413 * @skb: socket buffer to eat
2415 * This routine must be called with interrupts disabled or with the socket
2416 * locked so that the sk_buff queue operation is ok.
2418 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb)
2420 __skb_unlink(skb, &sk->sk_receive_queue);
2425 struct net *sock_net(const struct sock *sk)
2427 return read_pnet(&sk->sk_net);
2431 void sock_net_set(struct sock *sk, struct net *net)
2433 write_pnet(&sk->sk_net, net);
2436 static inline struct sock *skb_steal_sock(struct sk_buff *skb)
2439 struct sock *sk = skb->sk;
2441 skb->destructor = NULL;
2448 /* This helper checks if a socket is a full socket,
2449 * ie _not_ a timewait or request socket.
2451 static inline bool sk_fullsock(const struct sock *sk)
2453 return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV);
2456 /* Checks if this SKB belongs to an HW offloaded socket
2457 * and whether any SW fallbacks are required based on dev.
2459 static inline struct sk_buff *sk_validate_xmit_skb(struct sk_buff *skb,
2460 struct net_device *dev)
2462 #ifdef CONFIG_SOCK_VALIDATE_XMIT
2463 struct sock *sk = skb->sk;
2465 if (sk && sk_fullsock(sk) && sk->sk_validate_xmit_skb)
2466 skb = sk->sk_validate_xmit_skb(sk, dev, skb);
2472 /* This helper checks if a socket is a LISTEN or NEW_SYN_RECV
2473 * SYNACK messages can be attached to either ones (depending on SYNCOOKIE)
2475 static inline bool sk_listener(const struct sock *sk)
2477 return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV);
2480 void sock_enable_timestamp(struct sock *sk, int flag);
2481 int sock_get_timestamp(struct sock *, struct timeval __user *);
2482 int sock_get_timestampns(struct sock *, struct timespec __user *);
2483 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level,
2486 bool sk_ns_capable(const struct sock *sk,
2487 struct user_namespace *user_ns, int cap);
2488 bool sk_capable(const struct sock *sk, int cap);
2489 bool sk_net_capable(const struct sock *sk, int cap);
2491 void sk_get_meminfo(const struct sock *sk, u32 *meminfo);
2493 /* Take into consideration the size of the struct sk_buff overhead in the
2494 * determination of these values, since that is non-constant across
2495 * platforms. This makes socket queueing behavior and performance
2496 * not depend upon such differences.
2498 #define _SK_MEM_PACKETS 256
2499 #define _SK_MEM_OVERHEAD SKB_TRUESIZE(256)
2500 #define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2501 #define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2503 extern __u32 sysctl_wmem_max;
2504 extern __u32 sysctl_rmem_max;
2506 extern int sysctl_tstamp_allow_data;
2507 extern int sysctl_optmem_max;
2509 extern __u32 sysctl_wmem_default;
2510 extern __u32 sysctl_rmem_default;
2512 static inline int sk_get_wmem0(const struct sock *sk, const struct proto *proto)
2514 /* Does this proto have per netns sysctl_wmem ? */
2515 if (proto->sysctl_wmem_offset)
2516 return *(int *)((void *)sock_net(sk) + proto->sysctl_wmem_offset);
2518 return *proto->sysctl_wmem;
2521 static inline int sk_get_rmem0(const struct sock *sk, const struct proto *proto)
2523 /* Does this proto have per netns sysctl_rmem ? */
2524 if (proto->sysctl_rmem_offset)
2525 return *(int *)((void *)sock_net(sk) + proto->sysctl_rmem_offset);
2527 return *proto->sysctl_rmem;
2530 /* Default TCP Small queue budget is ~1 ms of data (1sec >> 10)
2531 * Some wifi drivers need to tweak it to get more chunks.
2532 * They can use this helper from their ndo_start_xmit()
2534 static inline void sk_pacing_shift_update(struct sock *sk, int val)
2536 if (!sk || !sk_fullsock(sk) || sk->sk_pacing_shift == val)
2538 sk->sk_pacing_shift = val;
2541 /* if a socket is bound to a device, check that the given device
2542 * index is either the same or that the socket is bound to an L3
2543 * master device and the given device index is also enslaved to
2546 static inline bool sk_dev_equal_l3scope(struct sock *sk, int dif)
2550 if (!sk->sk_bound_dev_if || sk->sk_bound_dev_if == dif)
2553 mdif = l3mdev_master_ifindex_by_index(sock_net(sk), dif);
2554 if (mdif && mdif == sk->sk_bound_dev_if)
2560 #endif /* _SOCK_H */