net: usb: pegasus: fix improper read if get_registers() fail
[linux/fpc-iii.git] / include / net / sock.h
blob116308632fae07af691ef04cfc1d0e42c5541748
1 /*
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
10 * Authors: Ross Biro
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>
15 * Fixes:
16 * Alan Cox : Volatiles in skbuff pointers. See
17 * skbuff comments. May be overdone,
18 * better to prove they can be removed
19 * than the reverse.
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.
40 #ifndef _SOCK_H
41 #define _SOCK_H
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 */
53 #include <linux/mm.h>
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>
64 #include <linux/filter.h>
65 #include <linux/rculist_nulls.h>
66 #include <linux/poll.h>
68 #include <linux/atomic.h>
69 #include <net/dst.h>
70 #include <net/checksum.h>
71 #include <net/tcp_states.h>
72 #include <linux/net_tstamp.h>
75 * This structure really needs to be cleaned up.
76 * Most of it is for TCP, and not used by any of
77 * the other protocols.
80 /* Define this to get the SOCK_DBG debugging facility. */
81 #define SOCK_DEBUGGING
82 #ifdef SOCK_DEBUGGING
83 #define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \
84 printk(KERN_DEBUG msg); } while (0)
85 #else
86 /* Validate arguments and do nothing */
87 static inline __printf(2, 3)
88 void SOCK_DEBUG(const struct sock *sk, const char *msg, ...)
91 #endif
93 /* This is the per-socket lock. The spinlock provides a synchronization
94 * between user contexts and software interrupt processing, whereas the
95 * mini-semaphore synchronizes multiple users amongst themselves.
97 typedef struct {
98 spinlock_t slock;
99 int owned;
100 wait_queue_head_t wq;
102 * We express the mutex-alike socket_lock semantics
103 * to the lock validator by explicitly managing
104 * the slock as a lock variant (in addition to
105 * the slock itself):
107 #ifdef CONFIG_DEBUG_LOCK_ALLOC
108 struct lockdep_map dep_map;
109 #endif
110 } socket_lock_t;
112 struct sock;
113 struct proto;
114 struct net;
116 typedef __u32 __bitwise __portpair;
117 typedef __u64 __bitwise __addrpair;
120 * struct sock_common - minimal network layer representation of sockets
121 * @skc_daddr: Foreign IPv4 addr
122 * @skc_rcv_saddr: Bound local IPv4 addr
123 * @skc_hash: hash value used with various protocol lookup tables
124 * @skc_u16hashes: two u16 hash values used by UDP lookup tables
125 * @skc_dport: placeholder for inet_dport/tw_dport
126 * @skc_num: placeholder for inet_num/tw_num
127 * @skc_family: network address family
128 * @skc_state: Connection state
129 * @skc_reuse: %SO_REUSEADDR setting
130 * @skc_reuseport: %SO_REUSEPORT setting
131 * @skc_bound_dev_if: bound device index if != 0
132 * @skc_bind_node: bind hash linkage for various protocol lookup tables
133 * @skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol
134 * @skc_prot: protocol handlers inside a network family
135 * @skc_net: reference to the network namespace of this socket
136 * @skc_node: main hash linkage for various protocol lookup tables
137 * @skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol
138 * @skc_tx_queue_mapping: tx queue number for this connection
139 * @skc_flags: place holder for sk_flags
140 * %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE,
141 * %SO_OOBINLINE settings, %SO_TIMESTAMPING settings
142 * @skc_incoming_cpu: record/match cpu processing incoming packets
143 * @skc_refcnt: reference count
145 * This is the minimal network layer representation of sockets, the header
146 * for struct sock and struct inet_timewait_sock.
148 struct sock_common {
149 /* skc_daddr and skc_rcv_saddr must be grouped on a 8 bytes aligned
150 * address on 64bit arches : cf INET_MATCH()
152 union {
153 __addrpair skc_addrpair;
154 struct {
155 __be32 skc_daddr;
156 __be32 skc_rcv_saddr;
159 union {
160 unsigned int skc_hash;
161 __u16 skc_u16hashes[2];
163 /* skc_dport && skc_num must be grouped as well */
164 union {
165 __portpair skc_portpair;
166 struct {
167 __be16 skc_dport;
168 __u16 skc_num;
172 unsigned short skc_family;
173 volatile unsigned char skc_state;
174 unsigned char skc_reuse:4;
175 unsigned char skc_reuseport:1;
176 unsigned char skc_ipv6only:1;
177 unsigned char skc_net_refcnt:1;
178 int skc_bound_dev_if;
179 union {
180 struct hlist_node skc_bind_node;
181 struct hlist_node skc_portaddr_node;
183 struct proto *skc_prot;
184 possible_net_t skc_net;
186 #if IS_ENABLED(CONFIG_IPV6)
187 struct in6_addr skc_v6_daddr;
188 struct in6_addr skc_v6_rcv_saddr;
189 #endif
191 atomic64_t skc_cookie;
193 /* following fields are padding to force
194 * offset(struct sock, sk_refcnt) == 128 on 64bit arches
195 * assuming IPV6 is enabled. We use this padding differently
196 * for different kind of 'sockets'
198 union {
199 unsigned long skc_flags;
200 struct sock *skc_listener; /* request_sock */
201 struct inet_timewait_death_row *skc_tw_dr; /* inet_timewait_sock */
204 * fields between dontcopy_begin/dontcopy_end
205 * are not copied in sock_copy()
207 /* private: */
208 int skc_dontcopy_begin[0];
209 /* public: */
210 union {
211 struct hlist_node skc_node;
212 struct hlist_nulls_node skc_nulls_node;
214 int skc_tx_queue_mapping;
215 union {
216 int skc_incoming_cpu;
217 u32 skc_rcv_wnd;
218 u32 skc_tw_rcv_nxt; /* struct tcp_timewait_sock */
221 atomic_t skc_refcnt;
222 /* private: */
223 int skc_dontcopy_end[0];
224 union {
225 u32 skc_rxhash;
226 u32 skc_window_clamp;
227 u32 skc_tw_snd_nxt; /* struct tcp_timewait_sock */
229 /* public: */
233 * struct sock - network layer representation of sockets
234 * @__sk_common: shared layout with inet_timewait_sock
235 * @sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
236 * @sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
237 * @sk_lock: synchronizer
238 * @sk_rcvbuf: size of receive buffer in bytes
239 * @sk_wq: sock wait queue and async head
240 * @sk_rx_dst: receive input route used by early demux
241 * @sk_dst_cache: destination cache
242 * @sk_policy: flow policy
243 * @sk_receive_queue: incoming packets
244 * @sk_wmem_alloc: transmit queue bytes committed
245 * @sk_write_queue: Packet sending queue
246 * @sk_omem_alloc: "o" is "option" or "other"
247 * @sk_wmem_queued: persistent queue size
248 * @sk_forward_alloc: space allocated forward
249 * @sk_napi_id: id of the last napi context to receive data for sk
250 * @sk_ll_usec: usecs to busypoll when there is no data
251 * @sk_allocation: allocation mode
252 * @sk_pacing_rate: Pacing rate (if supported by transport/packet scheduler)
253 * @sk_max_pacing_rate: Maximum pacing rate (%SO_MAX_PACING_RATE)
254 * @sk_sndbuf: size of send buffer in bytes
255 * @sk_padding: unused element for alignment
256 * @sk_no_check_tx: %SO_NO_CHECK setting, set checksum in TX packets
257 * @sk_no_check_rx: allow zero checksum in RX packets
258 * @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
259 * @sk_route_nocaps: forbidden route capabilities (e.g NETIF_F_GSO_MASK)
260 * @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
261 * @sk_gso_max_size: Maximum GSO segment size to build
262 * @sk_gso_max_segs: Maximum number of GSO segments
263 * @sk_lingertime: %SO_LINGER l_linger setting
264 * @sk_backlog: always used with the per-socket spinlock held
265 * @sk_callback_lock: used with the callbacks in the end of this struct
266 * @sk_error_queue: rarely used
267 * @sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt,
268 * IPV6_ADDRFORM for instance)
269 * @sk_err: last error
270 * @sk_err_soft: errors that don't cause failure but are the cause of a
271 * persistent failure not just 'timed out'
272 * @sk_drops: raw/udp drops counter
273 * @sk_ack_backlog: current listen backlog
274 * @sk_max_ack_backlog: listen backlog set in listen()
275 * @sk_priority: %SO_PRIORITY setting
276 * @sk_type: socket type (%SOCK_STREAM, etc)
277 * @sk_protocol: which protocol this socket belongs in this network family
278 * @sk_peer_pid: &struct pid for this socket's peer
279 * @sk_peer_cred: %SO_PEERCRED setting
280 * @sk_rcvlowat: %SO_RCVLOWAT setting
281 * @sk_rcvtimeo: %SO_RCVTIMEO setting
282 * @sk_sndtimeo: %SO_SNDTIMEO setting
283 * @sk_txhash: computed flow hash for use on transmit
284 * @sk_filter: socket filtering instructions
285 * @sk_timer: sock cleanup timer
286 * @sk_stamp: time stamp of last packet received
287 * @sk_stamp_seq: lock for accessing sk_stamp on 32 bit architectures only
288 * @sk_tsflags: SO_TIMESTAMPING socket options
289 * @sk_tskey: counter to disambiguate concurrent tstamp requests
290 * @sk_socket: Identd and reporting IO signals
291 * @sk_user_data: RPC layer private data
292 * @sk_frag: cached page frag
293 * @sk_peek_off: current peek_offset value
294 * @sk_send_head: front of stuff to transmit
295 * @sk_security: used by security modules
296 * @sk_mark: generic packet mark
297 * @sk_cgrp_data: cgroup data for this cgroup
298 * @sk_memcg: this socket's memory cgroup association
299 * @sk_write_pending: a write to stream socket waits to start
300 * @sk_state_change: callback to indicate change in the state of the sock
301 * @sk_data_ready: callback to indicate there is data to be processed
302 * @sk_write_space: callback to indicate there is bf sending space available
303 * @sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
304 * @sk_backlog_rcv: callback to process the backlog
305 * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
306 * @sk_reuseport_cb: reuseport group container
307 * @sk_rcu: used during RCU grace period
309 struct sock {
311 * Now struct inet_timewait_sock also uses sock_common, so please just
312 * don't add nothing before this first member (__sk_common) --acme
314 struct sock_common __sk_common;
315 #define sk_node __sk_common.skc_node
316 #define sk_nulls_node __sk_common.skc_nulls_node
317 #define sk_refcnt __sk_common.skc_refcnt
318 #define sk_tx_queue_mapping __sk_common.skc_tx_queue_mapping
320 #define sk_dontcopy_begin __sk_common.skc_dontcopy_begin
321 #define sk_dontcopy_end __sk_common.skc_dontcopy_end
322 #define sk_hash __sk_common.skc_hash
323 #define sk_portpair __sk_common.skc_portpair
324 #define sk_num __sk_common.skc_num
325 #define sk_dport __sk_common.skc_dport
326 #define sk_addrpair __sk_common.skc_addrpair
327 #define sk_daddr __sk_common.skc_daddr
328 #define sk_rcv_saddr __sk_common.skc_rcv_saddr
329 #define sk_family __sk_common.skc_family
330 #define sk_state __sk_common.skc_state
331 #define sk_reuse __sk_common.skc_reuse
332 #define sk_reuseport __sk_common.skc_reuseport
333 #define sk_ipv6only __sk_common.skc_ipv6only
334 #define sk_net_refcnt __sk_common.skc_net_refcnt
335 #define sk_bound_dev_if __sk_common.skc_bound_dev_if
336 #define sk_bind_node __sk_common.skc_bind_node
337 #define sk_prot __sk_common.skc_prot
338 #define sk_net __sk_common.skc_net
339 #define sk_v6_daddr __sk_common.skc_v6_daddr
340 #define sk_v6_rcv_saddr __sk_common.skc_v6_rcv_saddr
341 #define sk_cookie __sk_common.skc_cookie
342 #define sk_incoming_cpu __sk_common.skc_incoming_cpu
343 #define sk_flags __sk_common.skc_flags
344 #define sk_rxhash __sk_common.skc_rxhash
346 socket_lock_t sk_lock;
347 struct sk_buff_head sk_receive_queue;
349 * The backlog queue is special, it is always used with
350 * the per-socket spinlock held and requires low latency
351 * access. Therefore we special case it's implementation.
352 * Note : rmem_alloc is in this structure to fill a hole
353 * on 64bit arches, not because its logically part of
354 * backlog.
356 struct {
357 atomic_t rmem_alloc;
358 int len;
359 struct sk_buff *head;
360 struct sk_buff *tail;
361 } sk_backlog;
362 #define sk_rmem_alloc sk_backlog.rmem_alloc
363 int sk_forward_alloc;
365 __u32 sk_txhash;
366 #ifdef CONFIG_NET_RX_BUSY_POLL
367 unsigned int sk_napi_id;
368 unsigned int sk_ll_usec;
369 #endif
370 atomic_t sk_drops;
371 int sk_rcvbuf;
373 struct sk_filter __rcu *sk_filter;
374 union {
375 struct socket_wq __rcu *sk_wq;
376 struct socket_wq *sk_wq_raw;
378 #ifdef CONFIG_XFRM
379 struct xfrm_policy __rcu *sk_policy[2];
380 #endif
381 struct dst_entry *sk_rx_dst;
382 struct dst_entry __rcu *sk_dst_cache;
383 /* Note: 32bit hole on 64bit arches */
384 atomic_t sk_wmem_alloc;
385 atomic_t sk_omem_alloc;
386 int sk_sndbuf;
387 struct sk_buff_head sk_write_queue;
390 * Because of non atomicity rules, all
391 * changes are protected by socket lock.
393 kmemcheck_bitfield_begin(flags);
394 unsigned int sk_padding : 2,
395 sk_no_check_tx : 1,
396 sk_no_check_rx : 1,
397 sk_userlocks : 4,
398 sk_protocol : 8,
399 sk_type : 16;
400 #define SK_PROTOCOL_MAX U8_MAX
401 kmemcheck_bitfield_end(flags);
403 int sk_wmem_queued;
404 gfp_t sk_allocation;
405 u32 sk_pacing_rate; /* bytes per second */
406 u32 sk_max_pacing_rate;
407 netdev_features_t sk_route_caps;
408 netdev_features_t sk_route_nocaps;
409 int sk_gso_type;
410 unsigned int sk_gso_max_size;
411 u16 sk_gso_max_segs;
412 int sk_rcvlowat;
413 unsigned long sk_lingertime;
414 struct sk_buff_head sk_error_queue;
415 struct proto *sk_prot_creator;
416 rwlock_t sk_callback_lock;
417 int sk_err,
418 sk_err_soft;
419 u32 sk_ack_backlog;
420 u32 sk_max_ack_backlog;
421 __u32 sk_priority;
422 __u32 sk_mark;
423 struct pid *sk_peer_pid;
424 const struct cred *sk_peer_cred;
425 long sk_rcvtimeo;
426 long sk_sndtimeo;
427 struct timer_list sk_timer;
428 ktime_t sk_stamp;
429 #if BITS_PER_LONG==32
430 seqlock_t sk_stamp_seq;
431 #endif
432 u16 sk_tsflags;
433 u8 sk_shutdown;
434 u32 sk_tskey;
435 struct socket *sk_socket;
436 void *sk_user_data;
437 struct page_frag sk_frag;
438 struct sk_buff *sk_send_head;
439 __s32 sk_peek_off;
440 int sk_write_pending;
441 #ifdef CONFIG_SECURITY
442 void *sk_security;
443 #endif
444 struct sock_cgroup_data sk_cgrp_data;
445 struct mem_cgroup *sk_memcg;
446 void (*sk_state_change)(struct sock *sk);
447 void (*sk_data_ready)(struct sock *sk);
448 void (*sk_write_space)(struct sock *sk);
449 void (*sk_error_report)(struct sock *sk);
450 int (*sk_backlog_rcv)(struct sock *sk,
451 struct sk_buff *skb);
452 void (*sk_destruct)(struct sock *sk);
453 struct sock_reuseport __rcu *sk_reuseport_cb;
454 struct rcu_head sk_rcu;
457 #define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data)))
459 #define rcu_dereference_sk_user_data(sk) rcu_dereference(__sk_user_data((sk)))
460 #define rcu_assign_sk_user_data(sk, ptr) rcu_assign_pointer(__sk_user_data((sk)), ptr)
463 * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK
464 * or not whether his port will be reused by someone else. SK_FORCE_REUSE
465 * on a socket means that the socket will reuse everybody else's port
466 * without looking at the other's sk_reuse value.
469 #define SK_NO_REUSE 0
470 #define SK_CAN_REUSE 1
471 #define SK_FORCE_REUSE 2
473 int sk_set_peek_off(struct sock *sk, int val);
475 static inline int sk_peek_offset(struct sock *sk, int flags)
477 if (unlikely(flags & MSG_PEEK)) {
478 s32 off = READ_ONCE(sk->sk_peek_off);
479 if (off >= 0)
480 return off;
483 return 0;
486 static inline void sk_peek_offset_bwd(struct sock *sk, int val)
488 s32 off = READ_ONCE(sk->sk_peek_off);
490 if (unlikely(off >= 0)) {
491 off = max_t(s32, off - val, 0);
492 WRITE_ONCE(sk->sk_peek_off, off);
496 static inline void sk_peek_offset_fwd(struct sock *sk, int val)
498 sk_peek_offset_bwd(sk, -val);
502 * Hashed lists helper routines
504 static inline struct sock *sk_entry(const struct hlist_node *node)
506 return hlist_entry(node, struct sock, sk_node);
509 static inline struct sock *__sk_head(const struct hlist_head *head)
511 return hlist_entry(head->first, struct sock, sk_node);
514 static inline struct sock *sk_head(const struct hlist_head *head)
516 return hlist_empty(head) ? NULL : __sk_head(head);
519 static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head)
521 return hlist_nulls_entry(head->first, struct sock, sk_nulls_node);
524 static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head)
526 return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head);
529 static inline struct sock *sk_next(const struct sock *sk)
531 return sk->sk_node.next ?
532 hlist_entry(sk->sk_node.next, struct sock, sk_node) : NULL;
535 static inline struct sock *sk_nulls_next(const struct sock *sk)
537 return (!is_a_nulls(sk->sk_nulls_node.next)) ?
538 hlist_nulls_entry(sk->sk_nulls_node.next,
539 struct sock, sk_nulls_node) :
540 NULL;
543 static inline bool sk_unhashed(const struct sock *sk)
545 return hlist_unhashed(&sk->sk_node);
548 static inline bool sk_hashed(const struct sock *sk)
550 return !sk_unhashed(sk);
553 static inline void sk_node_init(struct hlist_node *node)
555 node->pprev = NULL;
558 static inline void sk_nulls_node_init(struct hlist_nulls_node *node)
560 node->pprev = NULL;
563 static inline void __sk_del_node(struct sock *sk)
565 __hlist_del(&sk->sk_node);
568 /* NB: equivalent to hlist_del_init_rcu */
569 static inline bool __sk_del_node_init(struct sock *sk)
571 if (sk_hashed(sk)) {
572 __sk_del_node(sk);
573 sk_node_init(&sk->sk_node);
574 return true;
576 return false;
579 /* Grab socket reference count. This operation is valid only
580 when sk is ALREADY grabbed f.e. it is found in hash table
581 or a list and the lookup is made under lock preventing hash table
582 modifications.
585 static __always_inline void sock_hold(struct sock *sk)
587 atomic_inc(&sk->sk_refcnt);
590 /* Ungrab socket in the context, which assumes that socket refcnt
591 cannot hit zero, f.e. it is true in context of any socketcall.
593 static __always_inline void __sock_put(struct sock *sk)
595 atomic_dec(&sk->sk_refcnt);
598 static inline bool sk_del_node_init(struct sock *sk)
600 bool rc = __sk_del_node_init(sk);
602 if (rc) {
603 /* paranoid for a while -acme */
604 WARN_ON(atomic_read(&sk->sk_refcnt) == 1);
605 __sock_put(sk);
607 return rc;
609 #define sk_del_node_init_rcu(sk) sk_del_node_init(sk)
611 static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk)
613 if (sk_hashed(sk)) {
614 hlist_nulls_del_init_rcu(&sk->sk_nulls_node);
615 return true;
617 return false;
620 static inline bool sk_nulls_del_node_init_rcu(struct sock *sk)
622 bool rc = __sk_nulls_del_node_init_rcu(sk);
624 if (rc) {
625 /* paranoid for a while -acme */
626 WARN_ON(atomic_read(&sk->sk_refcnt) == 1);
627 __sock_put(sk);
629 return rc;
632 static inline void __sk_add_node(struct sock *sk, struct hlist_head *list)
634 hlist_add_head(&sk->sk_node, list);
637 static inline void sk_add_node(struct sock *sk, struct hlist_head *list)
639 sock_hold(sk);
640 __sk_add_node(sk, list);
643 static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list)
645 sock_hold(sk);
646 if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport &&
647 sk->sk_family == AF_INET6)
648 hlist_add_tail_rcu(&sk->sk_node, list);
649 else
650 hlist_add_head_rcu(&sk->sk_node, list);
653 static inline void sk_add_node_tail_rcu(struct sock *sk, struct hlist_head *list)
655 sock_hold(sk);
656 hlist_add_tail_rcu(&sk->sk_node, list);
659 static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
661 hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list);
664 static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
666 sock_hold(sk);
667 __sk_nulls_add_node_rcu(sk, list);
670 static inline void __sk_del_bind_node(struct sock *sk)
672 __hlist_del(&sk->sk_bind_node);
675 static inline void sk_add_bind_node(struct sock *sk,
676 struct hlist_head *list)
678 hlist_add_head(&sk->sk_bind_node, list);
681 #define sk_for_each(__sk, list) \
682 hlist_for_each_entry(__sk, list, sk_node)
683 #define sk_for_each_rcu(__sk, list) \
684 hlist_for_each_entry_rcu(__sk, list, sk_node)
685 #define sk_nulls_for_each(__sk, node, list) \
686 hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)
687 #define sk_nulls_for_each_rcu(__sk, node, list) \
688 hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)
689 #define sk_for_each_from(__sk) \
690 hlist_for_each_entry_from(__sk, sk_node)
691 #define sk_nulls_for_each_from(__sk, node) \
692 if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \
693 hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node)
694 #define sk_for_each_safe(__sk, tmp, list) \
695 hlist_for_each_entry_safe(__sk, tmp, list, sk_node)
696 #define sk_for_each_bound(__sk, list) \
697 hlist_for_each_entry(__sk, list, sk_bind_node)
700 * sk_for_each_entry_offset_rcu - iterate over a list at a given struct offset
701 * @tpos: the type * to use as a loop cursor.
702 * @pos: the &struct hlist_node to use as a loop cursor.
703 * @head: the head for your list.
704 * @offset: offset of hlist_node within the struct.
707 #define sk_for_each_entry_offset_rcu(tpos, pos, head, offset) \
708 for (pos = rcu_dereference((head)->first); \
709 pos != NULL && \
710 ({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;}); \
711 pos = rcu_dereference(pos->next))
713 static inline struct user_namespace *sk_user_ns(struct sock *sk)
715 /* Careful only use this in a context where these parameters
716 * can not change and must all be valid, such as recvmsg from
717 * userspace.
719 return sk->sk_socket->file->f_cred->user_ns;
722 /* Sock flags */
723 enum sock_flags {
724 SOCK_DEAD,
725 SOCK_DONE,
726 SOCK_URGINLINE,
727 SOCK_KEEPOPEN,
728 SOCK_LINGER,
729 SOCK_DESTROY,
730 SOCK_BROADCAST,
731 SOCK_TIMESTAMP,
732 SOCK_ZAPPED,
733 SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */
734 SOCK_DBG, /* %SO_DEBUG setting */
735 SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
736 SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */
737 SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
738 SOCK_QUEUE_SHRUNK, /* write queue has been shrunk recently */
739 SOCK_MEMALLOC, /* VM depends on this socket for swapping */
740 SOCK_TIMESTAMPING_RX_SOFTWARE, /* %SOF_TIMESTAMPING_RX_SOFTWARE */
741 SOCK_FASYNC, /* fasync() active */
742 SOCK_RXQ_OVFL,
743 SOCK_ZEROCOPY, /* buffers from userspace */
744 SOCK_WIFI_STATUS, /* push wifi status to userspace */
745 SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS.
746 * Will use last 4 bytes of packet sent from
747 * user-space instead.
749 SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */
750 SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */
751 SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */
754 #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))
756 static inline void sock_copy_flags(struct sock *nsk, struct sock *osk)
758 nsk->sk_flags = osk->sk_flags;
761 static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
763 __set_bit(flag, &sk->sk_flags);
766 static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag)
768 __clear_bit(flag, &sk->sk_flags);
771 static inline bool sock_flag(const struct sock *sk, enum sock_flags flag)
773 return test_bit(flag, &sk->sk_flags);
776 #ifdef CONFIG_NET
777 extern struct static_key memalloc_socks;
778 static inline int sk_memalloc_socks(void)
780 return static_key_false(&memalloc_socks);
782 #else
784 static inline int sk_memalloc_socks(void)
786 return 0;
789 #endif
791 static inline gfp_t sk_gfp_mask(const struct sock *sk, gfp_t gfp_mask)
793 return gfp_mask | (sk->sk_allocation & __GFP_MEMALLOC);
796 static inline void sk_acceptq_removed(struct sock *sk)
798 sk->sk_ack_backlog--;
801 static inline void sk_acceptq_added(struct sock *sk)
803 sk->sk_ack_backlog++;
806 static inline bool sk_acceptq_is_full(const struct sock *sk)
808 return sk->sk_ack_backlog > sk->sk_max_ack_backlog;
812 * Compute minimal free write space needed to queue new packets.
814 static inline int sk_stream_min_wspace(const struct sock *sk)
816 return sk->sk_wmem_queued >> 1;
819 static inline int sk_stream_wspace(const struct sock *sk)
821 return sk->sk_sndbuf - sk->sk_wmem_queued;
824 void sk_stream_write_space(struct sock *sk);
826 /* OOB backlog add */
827 static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
829 /* dont let skb dst not refcounted, we are going to leave rcu lock */
830 skb_dst_force_safe(skb);
832 if (!sk->sk_backlog.tail)
833 sk->sk_backlog.head = skb;
834 else
835 sk->sk_backlog.tail->next = skb;
837 sk->sk_backlog.tail = skb;
838 skb->next = NULL;
842 * Take into account size of receive queue and backlog queue
843 * Do not take into account this skb truesize,
844 * to allow even a single big packet to come.
846 static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit)
848 unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc);
850 return qsize > limit;
853 /* The per-socket spinlock must be held here. */
854 static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb,
855 unsigned int limit)
857 if (sk_rcvqueues_full(sk, limit))
858 return -ENOBUFS;
861 * If the skb was allocated from pfmemalloc reserves, only
862 * allow SOCK_MEMALLOC sockets to use it as this socket is
863 * helping free memory
865 if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC))
866 return -ENOMEM;
868 __sk_add_backlog(sk, skb);
869 sk->sk_backlog.len += skb->truesize;
870 return 0;
873 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb);
875 static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
877 if (sk_memalloc_socks() && skb_pfmemalloc(skb))
878 return __sk_backlog_rcv(sk, skb);
880 return sk->sk_backlog_rcv(sk, skb);
883 static inline void sk_incoming_cpu_update(struct sock *sk)
885 sk->sk_incoming_cpu = raw_smp_processor_id();
888 static inline void sock_rps_record_flow_hash(__u32 hash)
890 #ifdef CONFIG_RPS
891 struct rps_sock_flow_table *sock_flow_table;
893 rcu_read_lock();
894 sock_flow_table = rcu_dereference(rps_sock_flow_table);
895 rps_record_sock_flow(sock_flow_table, hash);
896 rcu_read_unlock();
897 #endif
900 static inline void sock_rps_record_flow(const struct sock *sk)
902 #ifdef CONFIG_RPS
903 sock_rps_record_flow_hash(sk->sk_rxhash);
904 #endif
907 static inline void sock_rps_save_rxhash(struct sock *sk,
908 const struct sk_buff *skb)
910 #ifdef CONFIG_RPS
911 if (unlikely(sk->sk_rxhash != skb->hash))
912 sk->sk_rxhash = skb->hash;
913 #endif
916 static inline void sock_rps_reset_rxhash(struct sock *sk)
918 #ifdef CONFIG_RPS
919 sk->sk_rxhash = 0;
920 #endif
923 #define sk_wait_event(__sk, __timeo, __condition) \
924 ({ int __rc; \
925 release_sock(__sk); \
926 __rc = __condition; \
927 if (!__rc) { \
928 *(__timeo) = schedule_timeout(*(__timeo)); \
930 sched_annotate_sleep(); \
931 lock_sock(__sk); \
932 __rc = __condition; \
933 __rc; \
936 int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
937 int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
938 void sk_stream_wait_close(struct sock *sk, long timeo_p);
939 int sk_stream_error(struct sock *sk, int flags, int err);
940 void sk_stream_kill_queues(struct sock *sk);
941 void sk_set_memalloc(struct sock *sk);
942 void sk_clear_memalloc(struct sock *sk);
944 void __sk_flush_backlog(struct sock *sk);
946 static inline bool sk_flush_backlog(struct sock *sk)
948 if (unlikely(READ_ONCE(sk->sk_backlog.tail))) {
949 __sk_flush_backlog(sk);
950 return true;
952 return false;
955 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb);
957 struct request_sock_ops;
958 struct timewait_sock_ops;
959 struct inet_hashinfo;
960 struct raw_hashinfo;
961 struct module;
964 * caches using SLAB_DESTROY_BY_RCU should let .next pointer from nulls nodes
965 * un-modified. Special care is taken when initializing object to zero.
967 static inline void sk_prot_clear_nulls(struct sock *sk, int size)
969 if (offsetof(struct sock, sk_node.next) != 0)
970 memset(sk, 0, offsetof(struct sock, sk_node.next));
971 memset(&sk->sk_node.pprev, 0,
972 size - offsetof(struct sock, sk_node.pprev));
975 /* Networking protocol blocks we attach to sockets.
976 * socket layer -> transport layer interface
978 struct proto {
979 void (*close)(struct sock *sk,
980 long timeout);
981 int (*connect)(struct sock *sk,
982 struct sockaddr *uaddr,
983 int addr_len);
984 int (*disconnect)(struct sock *sk, int flags);
986 struct sock * (*accept)(struct sock *sk, int flags, int *err);
988 int (*ioctl)(struct sock *sk, int cmd,
989 unsigned long arg);
990 int (*init)(struct sock *sk);
991 void (*destroy)(struct sock *sk);
992 void (*shutdown)(struct sock *sk, int how);
993 int (*setsockopt)(struct sock *sk, int level,
994 int optname, char __user *optval,
995 unsigned int optlen);
996 int (*getsockopt)(struct sock *sk, int level,
997 int optname, char __user *optval,
998 int __user *option);
999 #ifdef CONFIG_COMPAT
1000 int (*compat_setsockopt)(struct sock *sk,
1001 int level,
1002 int optname, char __user *optval,
1003 unsigned int optlen);
1004 int (*compat_getsockopt)(struct sock *sk,
1005 int level,
1006 int optname, char __user *optval,
1007 int __user *option);
1008 int (*compat_ioctl)(struct sock *sk,
1009 unsigned int cmd, unsigned long arg);
1010 #endif
1011 int (*sendmsg)(struct sock *sk, struct msghdr *msg,
1012 size_t len);
1013 int (*recvmsg)(struct sock *sk, struct msghdr *msg,
1014 size_t len, int noblock, int flags,
1015 int *addr_len);
1016 int (*sendpage)(struct sock *sk, struct page *page,
1017 int offset, size_t size, int flags);
1018 int (*bind)(struct sock *sk,
1019 struct sockaddr *uaddr, int addr_len);
1021 int (*backlog_rcv) (struct sock *sk,
1022 struct sk_buff *skb);
1024 void (*release_cb)(struct sock *sk);
1026 /* Keeping track of sk's, looking them up, and port selection methods. */
1027 int (*hash)(struct sock *sk);
1028 void (*unhash)(struct sock *sk);
1029 void (*rehash)(struct sock *sk);
1030 int (*get_port)(struct sock *sk, unsigned short snum);
1032 /* Keeping track of sockets in use */
1033 #ifdef CONFIG_PROC_FS
1034 unsigned int inuse_idx;
1035 #endif
1037 bool (*stream_memory_free)(const struct sock *sk);
1038 /* Memory pressure */
1039 void (*enter_memory_pressure)(struct sock *sk);
1040 atomic_long_t *memory_allocated; /* Current allocated memory. */
1041 struct percpu_counter *sockets_allocated; /* Current number of sockets. */
1043 * Pressure flag: try to collapse.
1044 * Technical note: it is used by multiple contexts non atomically.
1045 * All the __sk_mem_schedule() is of this nature: accounting
1046 * is strict, actions are advisory and have some latency.
1048 int *memory_pressure;
1049 long *sysctl_mem;
1050 int *sysctl_wmem;
1051 int *sysctl_rmem;
1052 int max_header;
1053 bool no_autobind;
1055 struct kmem_cache *slab;
1056 unsigned int obj_size;
1057 int slab_flags;
1059 struct percpu_counter *orphan_count;
1061 struct request_sock_ops *rsk_prot;
1062 struct timewait_sock_ops *twsk_prot;
1064 union {
1065 struct inet_hashinfo *hashinfo;
1066 struct udp_table *udp_table;
1067 struct raw_hashinfo *raw_hash;
1068 } h;
1070 struct module *owner;
1072 char name[32];
1074 struct list_head node;
1075 #ifdef SOCK_REFCNT_DEBUG
1076 atomic_t socks;
1077 #endif
1078 int (*diag_destroy)(struct sock *sk, int err);
1081 int proto_register(struct proto *prot, int alloc_slab);
1082 void proto_unregister(struct proto *prot);
1084 #ifdef SOCK_REFCNT_DEBUG
1085 static inline void sk_refcnt_debug_inc(struct sock *sk)
1087 atomic_inc(&sk->sk_prot->socks);
1090 static inline void sk_refcnt_debug_dec(struct sock *sk)
1092 atomic_dec(&sk->sk_prot->socks);
1093 printk(KERN_DEBUG "%s socket %p released, %d are still alive\n",
1094 sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks));
1097 static inline void sk_refcnt_debug_release(const struct sock *sk)
1099 if (atomic_read(&sk->sk_refcnt) != 1)
1100 printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n",
1101 sk->sk_prot->name, sk, atomic_read(&sk->sk_refcnt));
1103 #else /* SOCK_REFCNT_DEBUG */
1104 #define sk_refcnt_debug_inc(sk) do { } while (0)
1105 #define sk_refcnt_debug_dec(sk) do { } while (0)
1106 #define sk_refcnt_debug_release(sk) do { } while (0)
1107 #endif /* SOCK_REFCNT_DEBUG */
1109 static inline bool sk_stream_memory_free(const struct sock *sk)
1111 if (sk->sk_wmem_queued >= sk->sk_sndbuf)
1112 return false;
1114 return sk->sk_prot->stream_memory_free ?
1115 sk->sk_prot->stream_memory_free(sk) : true;
1118 static inline bool sk_stream_is_writeable(const struct sock *sk)
1120 return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) &&
1121 sk_stream_memory_free(sk);
1124 static inline int sk_under_cgroup_hierarchy(struct sock *sk,
1125 struct cgroup *ancestor)
1127 #ifdef CONFIG_SOCK_CGROUP_DATA
1128 return cgroup_is_descendant(sock_cgroup_ptr(&sk->sk_cgrp_data),
1129 ancestor);
1130 #else
1131 return -ENOTSUPP;
1132 #endif
1135 static inline bool sk_has_memory_pressure(const struct sock *sk)
1137 return sk->sk_prot->memory_pressure != NULL;
1140 static inline bool sk_under_memory_pressure(const struct sock *sk)
1142 if (!sk->sk_prot->memory_pressure)
1143 return false;
1145 if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
1146 mem_cgroup_under_socket_pressure(sk->sk_memcg))
1147 return true;
1149 return !!*sk->sk_prot->memory_pressure;
1152 static inline void sk_leave_memory_pressure(struct sock *sk)
1154 int *memory_pressure = sk->sk_prot->memory_pressure;
1156 if (!memory_pressure)
1157 return;
1159 if (*memory_pressure)
1160 *memory_pressure = 0;
1163 static inline void sk_enter_memory_pressure(struct sock *sk)
1165 if (!sk->sk_prot->enter_memory_pressure)
1166 return;
1168 sk->sk_prot->enter_memory_pressure(sk);
1171 static inline long sk_prot_mem_limits(const struct sock *sk, int index)
1173 return sk->sk_prot->sysctl_mem[index];
1176 static inline long
1177 sk_memory_allocated(const struct sock *sk)
1179 return atomic_long_read(sk->sk_prot->memory_allocated);
1182 static inline long
1183 sk_memory_allocated_add(struct sock *sk, int amt)
1185 return atomic_long_add_return(amt, sk->sk_prot->memory_allocated);
1188 static inline void
1189 sk_memory_allocated_sub(struct sock *sk, int amt)
1191 atomic_long_sub(amt, sk->sk_prot->memory_allocated);
1194 static inline void sk_sockets_allocated_dec(struct sock *sk)
1196 percpu_counter_dec(sk->sk_prot->sockets_allocated);
1199 static inline void sk_sockets_allocated_inc(struct sock *sk)
1201 percpu_counter_inc(sk->sk_prot->sockets_allocated);
1204 static inline int
1205 sk_sockets_allocated_read_positive(struct sock *sk)
1207 return percpu_counter_read_positive(sk->sk_prot->sockets_allocated);
1210 static inline int
1211 proto_sockets_allocated_sum_positive(struct proto *prot)
1213 return percpu_counter_sum_positive(prot->sockets_allocated);
1216 static inline long
1217 proto_memory_allocated(struct proto *prot)
1219 return atomic_long_read(prot->memory_allocated);
1222 static inline bool
1223 proto_memory_pressure(struct proto *prot)
1225 if (!prot->memory_pressure)
1226 return false;
1227 return !!*prot->memory_pressure;
1231 #ifdef CONFIG_PROC_FS
1232 /* Called with local bh disabled */
1233 void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc);
1234 int sock_prot_inuse_get(struct net *net, struct proto *proto);
1235 #else
1236 static inline void sock_prot_inuse_add(struct net *net, struct proto *prot,
1237 int inc)
1240 #endif
1243 /* With per-bucket locks this operation is not-atomic, so that
1244 * this version is not worse.
1246 static inline int __sk_prot_rehash(struct sock *sk)
1248 sk->sk_prot->unhash(sk);
1249 return sk->sk_prot->hash(sk);
1252 /* About 10 seconds */
1253 #define SOCK_DESTROY_TIME (10*HZ)
1255 /* Sockets 0-1023 can't be bound to unless you are superuser */
1256 #define PROT_SOCK 1024
1258 #define SHUTDOWN_MASK 3
1259 #define RCV_SHUTDOWN 1
1260 #define SEND_SHUTDOWN 2
1262 #define SOCK_SNDBUF_LOCK 1
1263 #define SOCK_RCVBUF_LOCK 2
1264 #define SOCK_BINDADDR_LOCK 4
1265 #define SOCK_BINDPORT_LOCK 8
1267 struct socket_alloc {
1268 struct socket socket;
1269 struct inode vfs_inode;
1272 static inline struct socket *SOCKET_I(struct inode *inode)
1274 return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
1277 static inline struct inode *SOCK_INODE(struct socket *socket)
1279 return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
1283 * Functions for memory accounting
1285 int __sk_mem_schedule(struct sock *sk, int size, int kind);
1286 void __sk_mem_reclaim(struct sock *sk, int amount);
1288 #define SK_MEM_QUANTUM ((int)PAGE_SIZE)
1289 #define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM)
1290 #define SK_MEM_SEND 0
1291 #define SK_MEM_RECV 1
1293 static inline int sk_mem_pages(int amt)
1295 return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT;
1298 static inline bool sk_has_account(struct sock *sk)
1300 /* return true if protocol supports memory accounting */
1301 return !!sk->sk_prot->memory_allocated;
1304 static inline bool sk_wmem_schedule(struct sock *sk, int size)
1306 if (!sk_has_account(sk))
1307 return true;
1308 return size <= sk->sk_forward_alloc ||
1309 __sk_mem_schedule(sk, size, SK_MEM_SEND);
1312 static inline bool
1313 sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size)
1315 if (!sk_has_account(sk))
1316 return true;
1317 return size<= sk->sk_forward_alloc ||
1318 __sk_mem_schedule(sk, size, SK_MEM_RECV) ||
1319 skb_pfmemalloc(skb);
1322 static inline void sk_mem_reclaim(struct sock *sk)
1324 if (!sk_has_account(sk))
1325 return;
1326 if (sk->sk_forward_alloc >= SK_MEM_QUANTUM)
1327 __sk_mem_reclaim(sk, sk->sk_forward_alloc);
1330 static inline void sk_mem_reclaim_partial(struct sock *sk)
1332 if (!sk_has_account(sk))
1333 return;
1334 if (sk->sk_forward_alloc > SK_MEM_QUANTUM)
1335 __sk_mem_reclaim(sk, sk->sk_forward_alloc - 1);
1338 static inline void sk_mem_charge(struct sock *sk, int size)
1340 if (!sk_has_account(sk))
1341 return;
1342 sk->sk_forward_alloc -= size;
1345 static inline void sk_mem_uncharge(struct sock *sk, int size)
1347 if (!sk_has_account(sk))
1348 return;
1349 sk->sk_forward_alloc += size;
1351 /* Avoid a possible overflow.
1352 * TCP send queues can make this happen, if sk_mem_reclaim()
1353 * is not called and more than 2 GBytes are released at once.
1355 * If we reach 2 MBytes, reclaim 1 MBytes right now, there is
1356 * no need to hold that much forward allocation anyway.
1358 if (unlikely(sk->sk_forward_alloc >= 1 << 21))
1359 __sk_mem_reclaim(sk, 1 << 20);
1362 static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb)
1364 sock_set_flag(sk, SOCK_QUEUE_SHRUNK);
1365 sk->sk_wmem_queued -= skb->truesize;
1366 sk_mem_uncharge(sk, skb->truesize);
1367 __kfree_skb(skb);
1370 static inline void sock_release_ownership(struct sock *sk)
1372 if (sk->sk_lock.owned) {
1373 sk->sk_lock.owned = 0;
1375 /* The sk_lock has mutex_unlock() semantics: */
1376 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
1381 * Macro so as to not evaluate some arguments when
1382 * lockdep is not enabled.
1384 * Mark both the sk_lock and the sk_lock.slock as a
1385 * per-address-family lock class.
1387 #define sock_lock_init_class_and_name(sk, sname, skey, name, key) \
1388 do { \
1389 sk->sk_lock.owned = 0; \
1390 init_waitqueue_head(&sk->sk_lock.wq); \
1391 spin_lock_init(&(sk)->sk_lock.slock); \
1392 debug_check_no_locks_freed((void *)&(sk)->sk_lock, \
1393 sizeof((sk)->sk_lock)); \
1394 lockdep_set_class_and_name(&(sk)->sk_lock.slock, \
1395 (skey), (sname)); \
1396 lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \
1397 } while (0)
1399 #ifdef CONFIG_LOCKDEP
1400 static inline bool lockdep_sock_is_held(const struct sock *csk)
1402 struct sock *sk = (struct sock *)csk;
1404 return lockdep_is_held(&sk->sk_lock) ||
1405 lockdep_is_held(&sk->sk_lock.slock);
1407 #endif
1409 void lock_sock_nested(struct sock *sk, int subclass);
1411 static inline void lock_sock(struct sock *sk)
1413 lock_sock_nested(sk, 0);
1416 void release_sock(struct sock *sk);
1418 /* BH context may only use the following locking interface. */
1419 #define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock))
1420 #define bh_lock_sock_nested(__sk) \
1421 spin_lock_nested(&((__sk)->sk_lock.slock), \
1422 SINGLE_DEPTH_NESTING)
1423 #define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock))
1425 bool lock_sock_fast(struct sock *sk);
1427 * unlock_sock_fast - complement of lock_sock_fast
1428 * @sk: socket
1429 * @slow: slow mode
1431 * fast unlock socket for user context.
1432 * If slow mode is on, we call regular release_sock()
1434 static inline void unlock_sock_fast(struct sock *sk, bool slow)
1436 if (slow)
1437 release_sock(sk);
1438 else
1439 spin_unlock_bh(&sk->sk_lock.slock);
1442 /* Used by processes to "lock" a socket state, so that
1443 * interrupts and bottom half handlers won't change it
1444 * from under us. It essentially blocks any incoming
1445 * packets, so that we won't get any new data or any
1446 * packets that change the state of the socket.
1448 * While locked, BH processing will add new packets to
1449 * the backlog queue. This queue is processed by the
1450 * owner of the socket lock right before it is released.
1452 * Since ~2.3.5 it is also exclusive sleep lock serializing
1453 * accesses from user process context.
1456 static inline void sock_owned_by_me(const struct sock *sk)
1458 #ifdef CONFIG_LOCKDEP
1459 WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks);
1460 #endif
1463 static inline bool sock_owned_by_user(const struct sock *sk)
1465 sock_owned_by_me(sk);
1466 return sk->sk_lock.owned;
1469 /* no reclassification while locks are held */
1470 static inline bool sock_allow_reclassification(const struct sock *csk)
1472 struct sock *sk = (struct sock *)csk;
1474 return !sk->sk_lock.owned && !spin_is_locked(&sk->sk_lock.slock);
1477 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1478 struct proto *prot, int kern);
1479 void sk_free(struct sock *sk);
1480 void sk_destruct(struct sock *sk);
1481 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority);
1483 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1484 gfp_t priority);
1485 void __sock_wfree(struct sk_buff *skb);
1486 void sock_wfree(struct sk_buff *skb);
1487 void skb_orphan_partial(struct sk_buff *skb);
1488 void sock_rfree(struct sk_buff *skb);
1489 void sock_efree(struct sk_buff *skb);
1490 #ifdef CONFIG_INET
1491 void sock_edemux(struct sk_buff *skb);
1492 #else
1493 #define sock_edemux(skb) sock_efree(skb)
1494 #endif
1496 int sock_setsockopt(struct socket *sock, int level, int op,
1497 char __user *optval, unsigned int optlen);
1499 int sock_getsockopt(struct socket *sock, int level, int op,
1500 char __user *optval, int __user *optlen);
1501 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1502 int noblock, int *errcode);
1503 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1504 unsigned long data_len, int noblock,
1505 int *errcode, int max_page_order);
1506 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority);
1507 void sock_kfree_s(struct sock *sk, void *mem, int size);
1508 void sock_kzfree_s(struct sock *sk, void *mem, int size);
1509 void sk_send_sigurg(struct sock *sk);
1511 struct sockcm_cookie {
1512 u32 mark;
1513 u16 tsflags;
1516 int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg,
1517 struct sockcm_cookie *sockc);
1518 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
1519 struct sockcm_cookie *sockc);
1522 * Functions to fill in entries in struct proto_ops when a protocol
1523 * does not implement a particular function.
1525 int sock_no_bind(struct socket *, struct sockaddr *, int);
1526 int sock_no_connect(struct socket *, struct sockaddr *, int, int);
1527 int sock_no_socketpair(struct socket *, struct socket *);
1528 int sock_no_accept(struct socket *, struct socket *, int);
1529 int sock_no_getname(struct socket *, struct sockaddr *, int *, int);
1530 unsigned int sock_no_poll(struct file *, struct socket *,
1531 struct poll_table_struct *);
1532 int sock_no_ioctl(struct socket *, unsigned int, unsigned long);
1533 int sock_no_listen(struct socket *, int);
1534 int sock_no_shutdown(struct socket *, int);
1535 int sock_no_getsockopt(struct socket *, int , int, char __user *, int __user *);
1536 int sock_no_setsockopt(struct socket *, int, int, char __user *, unsigned int);
1537 int sock_no_sendmsg(struct socket *, struct msghdr *, size_t);
1538 int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int);
1539 int sock_no_mmap(struct file *file, struct socket *sock,
1540 struct vm_area_struct *vma);
1541 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset,
1542 size_t size, int flags);
1545 * Functions to fill in entries in struct proto_ops when a protocol
1546 * uses the inet style.
1548 int sock_common_getsockopt(struct socket *sock, int level, int optname,
1549 char __user *optval, int __user *optlen);
1550 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1551 int flags);
1552 int sock_common_setsockopt(struct socket *sock, int level, int optname,
1553 char __user *optval, unsigned int optlen);
1554 int compat_sock_common_getsockopt(struct socket *sock, int level,
1555 int optname, char __user *optval, int __user *optlen);
1556 int compat_sock_common_setsockopt(struct socket *sock, int level,
1557 int optname, char __user *optval, unsigned int optlen);
1559 void sk_common_release(struct sock *sk);
1562 * Default socket callbacks and setup code
1565 /* Initialise core socket variables */
1566 void sock_init_data(struct socket *sock, struct sock *sk);
1569 * Socket reference counting postulates.
1571 * * Each user of socket SHOULD hold a reference count.
1572 * * Each access point to socket (an hash table bucket, reference from a list,
1573 * running timer, skb in flight MUST hold a reference count.
1574 * * When reference count hits 0, it means it will never increase back.
1575 * * When reference count hits 0, it means that no references from
1576 * outside exist to this socket and current process on current CPU
1577 * is last user and may/should destroy this socket.
1578 * * sk_free is called from any context: process, BH, IRQ. When
1579 * it is called, socket has no references from outside -> sk_free
1580 * may release descendant resources allocated by the socket, but
1581 * to the time when it is called, socket is NOT referenced by any
1582 * hash tables, lists etc.
1583 * * Packets, delivered from outside (from network or from another process)
1584 * and enqueued on receive/error queues SHOULD NOT grab reference count,
1585 * when they sit in queue. Otherwise, packets will leak to hole, when
1586 * socket is looked up by one cpu and unhasing is made by another CPU.
1587 * It is true for udp/raw, netlink (leak to receive and error queues), tcp
1588 * (leak to backlog). Packet socket does all the processing inside
1589 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
1590 * use separate SMP lock, so that they are prone too.
1593 /* Ungrab socket and destroy it, if it was the last reference. */
1594 static inline void sock_put(struct sock *sk)
1596 if (atomic_dec_and_test(&sk->sk_refcnt))
1597 sk_free(sk);
1599 /* Generic version of sock_put(), dealing with all sockets
1600 * (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...)
1602 void sock_gen_put(struct sock *sk);
1604 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested,
1605 unsigned int trim_cap, bool refcounted);
1606 static inline int sk_receive_skb(struct sock *sk, struct sk_buff *skb,
1607 const int nested)
1609 return __sk_receive_skb(sk, skb, nested, 1, true);
1612 static inline void sk_tx_queue_set(struct sock *sk, int tx_queue)
1614 sk->sk_tx_queue_mapping = tx_queue;
1617 static inline void sk_tx_queue_clear(struct sock *sk)
1619 sk->sk_tx_queue_mapping = -1;
1622 static inline int sk_tx_queue_get(const struct sock *sk)
1624 return sk ? sk->sk_tx_queue_mapping : -1;
1627 static inline void sk_set_socket(struct sock *sk, struct socket *sock)
1629 sk_tx_queue_clear(sk);
1630 sk->sk_socket = sock;
1633 static inline wait_queue_head_t *sk_sleep(struct sock *sk)
1635 BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0);
1636 return &rcu_dereference_raw(sk->sk_wq)->wait;
1638 /* Detach socket from process context.
1639 * Announce socket dead, detach it from wait queue and inode.
1640 * Note that parent inode held reference count on this struct sock,
1641 * we do not release it in this function, because protocol
1642 * probably wants some additional cleanups or even continuing
1643 * to work with this socket (TCP).
1645 static inline void sock_orphan(struct sock *sk)
1647 write_lock_bh(&sk->sk_callback_lock);
1648 sock_set_flag(sk, SOCK_DEAD);
1649 sk_set_socket(sk, NULL);
1650 sk->sk_wq = NULL;
1651 write_unlock_bh(&sk->sk_callback_lock);
1654 static inline void sock_graft(struct sock *sk, struct socket *parent)
1656 write_lock_bh(&sk->sk_callback_lock);
1657 sk->sk_wq = parent->wq;
1658 parent->sk = sk;
1659 sk_set_socket(sk, parent);
1660 security_sock_graft(sk, parent);
1661 write_unlock_bh(&sk->sk_callback_lock);
1664 kuid_t sock_i_uid(struct sock *sk);
1665 unsigned long sock_i_ino(struct sock *sk);
1667 static inline u32 net_tx_rndhash(void)
1669 u32 v = prandom_u32();
1671 return v ?: 1;
1674 static inline void sk_set_txhash(struct sock *sk)
1676 sk->sk_txhash = net_tx_rndhash();
1679 static inline void sk_rethink_txhash(struct sock *sk)
1681 if (sk->sk_txhash)
1682 sk_set_txhash(sk);
1685 static inline struct dst_entry *
1686 __sk_dst_get(struct sock *sk)
1688 return rcu_dereference_check(sk->sk_dst_cache,
1689 lockdep_sock_is_held(sk));
1692 static inline struct dst_entry *
1693 sk_dst_get(struct sock *sk)
1695 struct dst_entry *dst;
1697 rcu_read_lock();
1698 dst = rcu_dereference(sk->sk_dst_cache);
1699 if (dst && !atomic_inc_not_zero(&dst->__refcnt))
1700 dst = NULL;
1701 rcu_read_unlock();
1702 return dst;
1705 static inline void dst_negative_advice(struct sock *sk)
1707 struct dst_entry *ndst, *dst = __sk_dst_get(sk);
1709 sk_rethink_txhash(sk);
1711 if (dst && dst->ops->negative_advice) {
1712 ndst = dst->ops->negative_advice(dst);
1714 if (ndst != dst) {
1715 rcu_assign_pointer(sk->sk_dst_cache, ndst);
1716 sk_tx_queue_clear(sk);
1721 static inline void
1722 __sk_dst_set(struct sock *sk, struct dst_entry *dst)
1724 struct dst_entry *old_dst;
1726 sk_tx_queue_clear(sk);
1728 * This can be called while sk is owned by the caller only,
1729 * with no state that can be checked in a rcu_dereference_check() cond
1731 old_dst = rcu_dereference_raw(sk->sk_dst_cache);
1732 rcu_assign_pointer(sk->sk_dst_cache, dst);
1733 dst_release(old_dst);
1736 static inline void
1737 sk_dst_set(struct sock *sk, struct dst_entry *dst)
1739 struct dst_entry *old_dst;
1741 sk_tx_queue_clear(sk);
1742 old_dst = xchg((__force struct dst_entry **)&sk->sk_dst_cache, dst);
1743 dst_release(old_dst);
1746 static inline void
1747 __sk_dst_reset(struct sock *sk)
1749 __sk_dst_set(sk, NULL);
1752 static inline void
1753 sk_dst_reset(struct sock *sk)
1755 sk_dst_set(sk, NULL);
1758 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
1760 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
1762 bool sk_mc_loop(struct sock *sk);
1764 static inline bool sk_can_gso(const struct sock *sk)
1766 return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type);
1769 void sk_setup_caps(struct sock *sk, struct dst_entry *dst);
1771 static inline void sk_nocaps_add(struct sock *sk, netdev_features_t flags)
1773 sk->sk_route_nocaps |= flags;
1774 sk->sk_route_caps &= ~flags;
1777 static inline bool sk_check_csum_caps(struct sock *sk)
1779 return (sk->sk_route_caps & NETIF_F_HW_CSUM) ||
1780 (sk->sk_family == PF_INET &&
1781 (sk->sk_route_caps & NETIF_F_IP_CSUM)) ||
1782 (sk->sk_family == PF_INET6 &&
1783 (sk->sk_route_caps & NETIF_F_IPV6_CSUM));
1786 static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
1787 struct iov_iter *from, char *to,
1788 int copy, int offset)
1790 if (skb->ip_summed == CHECKSUM_NONE) {
1791 __wsum csum = 0;
1792 if (csum_and_copy_from_iter(to, copy, &csum, from) != copy)
1793 return -EFAULT;
1794 skb->csum = csum_block_add(skb->csum, csum, offset);
1795 } else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
1796 if (copy_from_iter_nocache(to, copy, from) != copy)
1797 return -EFAULT;
1798 } else if (copy_from_iter(to, copy, from) != copy)
1799 return -EFAULT;
1801 return 0;
1804 static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
1805 struct iov_iter *from, int copy)
1807 int err, offset = skb->len;
1809 err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy),
1810 copy, offset);
1811 if (err)
1812 __skb_trim(skb, offset);
1814 return err;
1817 static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from,
1818 struct sk_buff *skb,
1819 struct page *page,
1820 int off, int copy)
1822 int err;
1824 err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off,
1825 copy, skb->len);
1826 if (err)
1827 return err;
1829 skb->len += copy;
1830 skb->data_len += copy;
1831 skb->truesize += copy;
1832 sk->sk_wmem_queued += copy;
1833 sk_mem_charge(sk, copy);
1834 return 0;
1838 * sk_wmem_alloc_get - returns write allocations
1839 * @sk: socket
1841 * Returns sk_wmem_alloc minus initial offset of one
1843 static inline int sk_wmem_alloc_get(const struct sock *sk)
1845 return atomic_read(&sk->sk_wmem_alloc) - 1;
1849 * sk_rmem_alloc_get - returns read allocations
1850 * @sk: socket
1852 * Returns sk_rmem_alloc
1854 static inline int sk_rmem_alloc_get(const struct sock *sk)
1856 return atomic_read(&sk->sk_rmem_alloc);
1860 * sk_has_allocations - check if allocations are outstanding
1861 * @sk: socket
1863 * Returns true if socket has write or read allocations
1865 static inline bool sk_has_allocations(const struct sock *sk)
1867 return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk);
1871 * skwq_has_sleeper - check if there are any waiting processes
1872 * @wq: struct socket_wq
1874 * Returns true if socket_wq has waiting processes
1876 * The purpose of the skwq_has_sleeper and sock_poll_wait is to wrap the memory
1877 * barrier call. They were added due to the race found within the tcp code.
1879 * Consider following tcp code paths:
1881 * CPU1 CPU2
1883 * sys_select receive packet
1884 * ... ...
1885 * __add_wait_queue update tp->rcv_nxt
1886 * ... ...
1887 * tp->rcv_nxt check sock_def_readable
1888 * ... {
1889 * schedule rcu_read_lock();
1890 * wq = rcu_dereference(sk->sk_wq);
1891 * if (wq && waitqueue_active(&wq->wait))
1892 * wake_up_interruptible(&wq->wait)
1893 * ...
1896 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
1897 * in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1
1898 * could then endup calling schedule and sleep forever if there are no more
1899 * data on the socket.
1902 static inline bool skwq_has_sleeper(struct socket_wq *wq)
1904 return wq && wq_has_sleeper(&wq->wait);
1908 * sock_poll_wait - place memory barrier behind the poll_wait call.
1909 * @filp: file
1910 * @wait_address: socket wait queue
1911 * @p: poll_table
1913 * See the comments in the wq_has_sleeper function.
1915 static inline void sock_poll_wait(struct file *filp,
1916 wait_queue_head_t *wait_address, poll_table *p)
1918 if (!poll_does_not_wait(p) && wait_address) {
1919 poll_wait(filp, wait_address, p);
1920 /* We need to be sure we are in sync with the
1921 * socket flags modification.
1923 * This memory barrier is paired in the wq_has_sleeper.
1925 smp_mb();
1929 static inline void skb_set_hash_from_sk(struct sk_buff *skb, struct sock *sk)
1931 if (sk->sk_txhash) {
1932 skb->l4_hash = 1;
1933 skb->hash = sk->sk_txhash;
1937 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk);
1940 * Queue a received datagram if it will fit. Stream and sequenced
1941 * protocols can't normally use this as they need to fit buffers in
1942 * and play with them.
1944 * Inlined as it's very short and called for pretty much every
1945 * packet ever received.
1947 static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
1949 skb_orphan(skb);
1950 skb->sk = sk;
1951 skb->destructor = sock_rfree;
1952 atomic_add(skb->truesize, &sk->sk_rmem_alloc);
1953 sk_mem_charge(sk, skb->truesize);
1956 void sk_reset_timer(struct sock *sk, struct timer_list *timer,
1957 unsigned long expires);
1959 void sk_stop_timer(struct sock *sk, struct timer_list *timer);
1961 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
1962 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
1964 int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
1965 struct sk_buff *sock_dequeue_err_skb(struct sock *sk);
1968 * Recover an error report and clear atomically
1971 static inline int sock_error(struct sock *sk)
1973 int err;
1974 if (likely(!sk->sk_err))
1975 return 0;
1976 err = xchg(&sk->sk_err, 0);
1977 return -err;
1980 static inline unsigned long sock_wspace(struct sock *sk)
1982 int amt = 0;
1984 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
1985 amt = sk->sk_sndbuf - atomic_read(&sk->sk_wmem_alloc);
1986 if (amt < 0)
1987 amt = 0;
1989 return amt;
1992 /* Note:
1993 * We use sk->sk_wq_raw, from contexts knowing this
1994 * pointer is not NULL and cannot disappear/change.
1996 static inline void sk_set_bit(int nr, struct sock *sk)
1998 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
1999 !sock_flag(sk, SOCK_FASYNC))
2000 return;
2002 set_bit(nr, &sk->sk_wq_raw->flags);
2005 static inline void sk_clear_bit(int nr, struct sock *sk)
2007 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2008 !sock_flag(sk, SOCK_FASYNC))
2009 return;
2011 clear_bit(nr, &sk->sk_wq_raw->flags);
2014 static inline void sk_wake_async(const struct sock *sk, int how, int band)
2016 if (sock_flag(sk, SOCK_FASYNC)) {
2017 rcu_read_lock();
2018 sock_wake_async(rcu_dereference(sk->sk_wq), how, band);
2019 rcu_read_unlock();
2023 /* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might
2024 * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak.
2025 * Note: for send buffers, TCP works better if we can build two skbs at
2026 * minimum.
2028 #define TCP_SKB_MIN_TRUESIZE (2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff)))
2030 #define SOCK_MIN_SNDBUF (TCP_SKB_MIN_TRUESIZE * 2)
2031 #define SOCK_MIN_RCVBUF TCP_SKB_MIN_TRUESIZE
2033 static inline void sk_stream_moderate_sndbuf(struct sock *sk)
2035 if (!(sk->sk_userlocks & SOCK_SNDBUF_LOCK)) {
2036 sk->sk_sndbuf = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
2037 sk->sk_sndbuf = max_t(u32, sk->sk_sndbuf, SOCK_MIN_SNDBUF);
2041 struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp,
2042 bool force_schedule);
2045 * sk_page_frag - return an appropriate page_frag
2046 * @sk: socket
2048 * If socket allocation mode allows current thread to sleep, it means its
2049 * safe to use the per task page_frag instead of the per socket one.
2051 static inline struct page_frag *sk_page_frag(struct sock *sk)
2053 if (gfpflags_allow_blocking(sk->sk_allocation))
2054 return &current->task_frag;
2056 return &sk->sk_frag;
2059 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag);
2062 * Default write policy as shown to user space via poll/select/SIGIO
2064 static inline bool sock_writeable(const struct sock *sk)
2066 return atomic_read(&sk->sk_wmem_alloc) < (sk->sk_sndbuf >> 1);
2069 static inline gfp_t gfp_any(void)
2071 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2074 static inline long sock_rcvtimeo(const struct sock *sk, bool noblock)
2076 return noblock ? 0 : sk->sk_rcvtimeo;
2079 static inline long sock_sndtimeo(const struct sock *sk, bool noblock)
2081 return noblock ? 0 : sk->sk_sndtimeo;
2084 static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
2086 return (waitall ? len : min_t(int, sk->sk_rcvlowat, len)) ? : 1;
2089 /* Alas, with timeout socket operations are not restartable.
2090 * Compare this to poll().
2092 static inline int sock_intr_errno(long timeo)
2094 return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
2097 struct sock_skb_cb {
2098 u32 dropcount;
2101 /* Store sock_skb_cb at the end of skb->cb[] so protocol families
2102 * using skb->cb[] would keep using it directly and utilize its
2103 * alignement guarantee.
2105 #define SOCK_SKB_CB_OFFSET ((FIELD_SIZEOF(struct sk_buff, cb) - \
2106 sizeof(struct sock_skb_cb)))
2108 #define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \
2109 SOCK_SKB_CB_OFFSET))
2111 #define sock_skb_cb_check_size(size) \
2112 BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET)
2114 static inline void
2115 sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb)
2117 SOCK_SKB_CB(skb)->dropcount = atomic_read(&sk->sk_drops);
2120 static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb)
2122 int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs);
2124 atomic_add(segs, &sk->sk_drops);
2127 static inline ktime_t sock_read_timestamp(struct sock *sk)
2129 #if BITS_PER_LONG==32
2130 unsigned int seq;
2131 ktime_t kt;
2133 do {
2134 seq = read_seqbegin(&sk->sk_stamp_seq);
2135 kt = sk->sk_stamp;
2136 } while (read_seqretry(&sk->sk_stamp_seq, seq));
2138 return kt;
2139 #else
2140 return sk->sk_stamp;
2141 #endif
2144 static inline void sock_write_timestamp(struct sock *sk, ktime_t kt)
2146 #if BITS_PER_LONG==32
2147 write_seqlock(&sk->sk_stamp_seq);
2148 sk->sk_stamp = kt;
2149 write_sequnlock(&sk->sk_stamp_seq);
2150 #else
2151 sk->sk_stamp = kt;
2152 #endif
2155 void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
2156 struct sk_buff *skb);
2157 void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
2158 struct sk_buff *skb);
2160 static inline void
2161 sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
2163 ktime_t kt = skb->tstamp;
2164 struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
2167 * generate control messages if
2168 * - receive time stamping in software requested
2169 * - software time stamp available and wanted
2170 * - hardware time stamps available and wanted
2172 if (sock_flag(sk, SOCK_RCVTSTAMP) ||
2173 (sk->sk_tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) ||
2174 (kt.tv64 && sk->sk_tsflags & SOF_TIMESTAMPING_SOFTWARE) ||
2175 (hwtstamps->hwtstamp.tv64 &&
2176 (sk->sk_tsflags & SOF_TIMESTAMPING_RAW_HARDWARE)))
2177 __sock_recv_timestamp(msg, sk, skb);
2178 else
2179 sock_write_timestamp(sk, kt);
2181 if (sock_flag(sk, SOCK_WIFI_STATUS) && skb->wifi_acked_valid)
2182 __sock_recv_wifi_status(msg, sk, skb);
2185 void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2186 struct sk_buff *skb);
2188 static inline void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2189 struct sk_buff *skb)
2191 #define FLAGS_TS_OR_DROPS ((1UL << SOCK_RXQ_OVFL) | \
2192 (1UL << SOCK_RCVTSTAMP))
2193 #define TSFLAGS_ANY (SOF_TIMESTAMPING_SOFTWARE | \
2194 SOF_TIMESTAMPING_RAW_HARDWARE)
2196 if (sk->sk_flags & FLAGS_TS_OR_DROPS || sk->sk_tsflags & TSFLAGS_ANY)
2197 __sock_recv_ts_and_drops(msg, sk, skb);
2198 else
2199 sock_write_timestamp(sk, skb->tstamp);
2202 void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags);
2205 * sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
2206 * @sk: socket sending this packet
2207 * @tsflags: timestamping flags to use
2208 * @tx_flags: completed with instructions for time stamping
2210 * Note : callers should take care of initial *tx_flags value (usually 0)
2212 static inline void sock_tx_timestamp(const struct sock *sk, __u16 tsflags,
2213 __u8 *tx_flags)
2215 if (unlikely(tsflags))
2216 __sock_tx_timestamp(tsflags, tx_flags);
2217 if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS)))
2218 *tx_flags |= SKBTX_WIFI_STATUS;
2222 * sk_eat_skb - Release a skb if it is no longer needed
2223 * @sk: socket to eat this skb from
2224 * @skb: socket buffer to eat
2226 * This routine must be called with interrupts disabled or with the socket
2227 * locked so that the sk_buff queue operation is ok.
2229 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb)
2231 __skb_unlink(skb, &sk->sk_receive_queue);
2232 __kfree_skb(skb);
2235 static inline
2236 struct net *sock_net(const struct sock *sk)
2238 return read_pnet(&sk->sk_net);
2241 static inline
2242 void sock_net_set(struct sock *sk, struct net *net)
2244 write_pnet(&sk->sk_net, net);
2247 static inline struct sock *skb_steal_sock(struct sk_buff *skb)
2249 if (skb->sk) {
2250 struct sock *sk = skb->sk;
2252 skb->destructor = NULL;
2253 skb->sk = NULL;
2254 return sk;
2256 return NULL;
2259 /* This helper checks if a socket is a full socket,
2260 * ie _not_ a timewait or request socket.
2262 static inline bool sk_fullsock(const struct sock *sk)
2264 return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV);
2267 /* This helper checks if a socket is a LISTEN or NEW_SYN_RECV
2268 * SYNACK messages can be attached to either ones (depending on SYNCOOKIE)
2270 static inline bool sk_listener(const struct sock *sk)
2272 return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV);
2276 * sk_state_load - read sk->sk_state for lockless contexts
2277 * @sk: socket pointer
2279 * Paired with sk_state_store(). Used in places we do not hold socket lock :
2280 * tcp_diag_get_info(), tcp_get_info(), tcp_poll(), get_tcp4_sock() ...
2282 static inline int sk_state_load(const struct sock *sk)
2284 return smp_load_acquire(&sk->sk_state);
2288 * sk_state_store - update sk->sk_state
2289 * @sk: socket pointer
2290 * @newstate: new state
2292 * Paired with sk_state_load(). Should be used in contexts where
2293 * state change might impact lockless readers.
2295 static inline void sk_state_store(struct sock *sk, int newstate)
2297 smp_store_release(&sk->sk_state, newstate);
2300 void sock_enable_timestamp(struct sock *sk, int flag);
2301 int sock_get_timestamp(struct sock *, struct timeval __user *);
2302 int sock_get_timestampns(struct sock *, struct timespec __user *);
2303 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level,
2304 int type);
2306 bool sk_ns_capable(const struct sock *sk,
2307 struct user_namespace *user_ns, int cap);
2308 bool sk_capable(const struct sock *sk, int cap);
2309 bool sk_net_capable(const struct sock *sk, int cap);
2311 extern __u32 sysctl_wmem_max;
2312 extern __u32 sysctl_rmem_max;
2314 extern int sysctl_tstamp_allow_data;
2315 extern int sysctl_optmem_max;
2317 extern __u32 sysctl_wmem_default;
2318 extern __u32 sysctl_rmem_default;
2320 #endif /* _SOCK_H */