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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.
5 *
6 * Definitions for the AF_INET socket handler.
7 *
8 * Version: @(#)sock.h 1.0.4 05/13/93
9 *
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>
14 *
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
33 *
34 *
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.
39 */
40#ifndef _SOCK_H
41#define _SOCK_H
42
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/module.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
58#include <linux/filter.h>
59#include <linux/rculist_nulls.h>
60#include <linux/poll.h>
61
62#include <linux/atomic.h>
63#include <net/dst.h>
64#include <net/checksum.h>
65
66/*
67 * This structure really needs to be cleaned up.
68 * Most of it is for TCP, and not used by any of
69 * the other protocols.
70 */
71
72/* Define this to get the SOCK_DBG debugging facility. */
73#define SOCK_DEBUGGING
74#ifdef SOCK_DEBUGGING
75#define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \
76 printk(KERN_DEBUG msg); } while (0)
77#else
78/* Validate arguments and do nothing */
79static inline void __attribute__ ((format (printf, 2, 3)))
80SOCK_DEBUG(struct sock *sk, const char *msg, ...)
81{
82}
83#endif
84
85/* This is the per-socket lock. The spinlock provides a synchronization
86 * between user contexts and software interrupt processing, whereas the
87 * mini-semaphore synchronizes multiple users amongst themselves.
88 */
89typedef struct {
90 spinlock_t slock;
91 int owned;
92 wait_queue_head_t wq;
93 /*
94 * We express the mutex-alike socket_lock semantics
95 * to the lock validator by explicitly managing
96 * the slock as a lock variant (in addition to
97 * the slock itself):
98 */
99#ifdef CONFIG_DEBUG_LOCK_ALLOC
100 struct lockdep_map dep_map;
101#endif
102} socket_lock_t;
103
104struct sock;
105struct proto;
106struct net;
107
108/**
109 * struct sock_common - minimal network layer representation of sockets
110 * @skc_daddr: Foreign IPv4 addr
111 * @skc_rcv_saddr: Bound local IPv4 addr
112 * @skc_hash: hash value used with various protocol lookup tables
113 * @skc_u16hashes: two u16 hash values used by UDP lookup tables
114 * @skc_family: network address family
115 * @skc_state: Connection state
116 * @skc_reuse: %SO_REUSEADDR setting
117 * @skc_bound_dev_if: bound device index if != 0
118 * @skc_bind_node: bind hash linkage for various protocol lookup tables
119 * @skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol
120 * @skc_prot: protocol handlers inside a network family
121 * @skc_net: reference to the network namespace of this socket
122 * @skc_node: main hash linkage for various protocol lookup tables
123 * @skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol
124 * @skc_tx_queue_mapping: tx queue number for this connection
125 * @skc_refcnt: reference count
126 *
127 * This is the minimal network layer representation of sockets, the header
128 * for struct sock and struct inet_timewait_sock.
129 */
130struct sock_common {
131 /* skc_daddr and skc_rcv_saddr must be grouped :
132 * cf INET_MATCH() and INET_TW_MATCH()
133 */
134 __be32 skc_daddr;
135 __be32 skc_rcv_saddr;
136
137 union {
138 unsigned int skc_hash;
139 __u16 skc_u16hashes[2];
140 };
141 unsigned short skc_family;
142 volatile unsigned char skc_state;
143 unsigned char skc_reuse;
144 int skc_bound_dev_if;
145 union {
146 struct hlist_node skc_bind_node;
147 struct hlist_nulls_node skc_portaddr_node;
148 };
149 struct proto *skc_prot;
150#ifdef CONFIG_NET_NS
151 struct net *skc_net;
152#endif
153 /*
154 * fields between dontcopy_begin/dontcopy_end
155 * are not copied in sock_copy()
156 */
157 /* private: */
158 int skc_dontcopy_begin[0];
159 /* public: */
160 union {
161 struct hlist_node skc_node;
162 struct hlist_nulls_node skc_nulls_node;
163 };
164 int skc_tx_queue_mapping;
165 atomic_t skc_refcnt;
166 /* private: */
167 int skc_dontcopy_end[0];
168 /* public: */
169};
170
171/**
172 * struct sock - network layer representation of sockets
173 * @__sk_common: shared layout with inet_timewait_sock
174 * @sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
175 * @sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
176 * @sk_lock: synchronizer
177 * @sk_rcvbuf: size of receive buffer in bytes
178 * @sk_wq: sock wait queue and async head
179 * @sk_dst_cache: destination cache
180 * @sk_dst_lock: destination cache lock
181 * @sk_policy: flow policy
182 * @sk_receive_queue: incoming packets
183 * @sk_wmem_alloc: transmit queue bytes committed
184 * @sk_write_queue: Packet sending queue
185 * @sk_async_wait_queue: DMA copied packets
186 * @sk_omem_alloc: "o" is "option" or "other"
187 * @sk_wmem_queued: persistent queue size
188 * @sk_forward_alloc: space allocated forward
189 * @sk_allocation: allocation mode
190 * @sk_sndbuf: size of send buffer in bytes
191 * @sk_flags: %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE,
192 * %SO_OOBINLINE settings, %SO_TIMESTAMPING settings
193 * @sk_no_check: %SO_NO_CHECK setting, wether or not checkup packets
194 * @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
195 * @sk_route_nocaps: forbidden route capabilities (e.g NETIF_F_GSO_MASK)
196 * @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
197 * @sk_gso_max_size: Maximum GSO segment size to build
198 * @sk_lingertime: %SO_LINGER l_linger setting
199 * @sk_backlog: always used with the per-socket spinlock held
200 * @sk_callback_lock: used with the callbacks in the end of this struct
201 * @sk_error_queue: rarely used
202 * @sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt,
203 * IPV6_ADDRFORM for instance)
204 * @sk_err: last error
205 * @sk_err_soft: errors that don't cause failure but are the cause of a
206 * persistent failure not just 'timed out'
207 * @sk_drops: raw/udp drops counter
208 * @sk_ack_backlog: current listen backlog
209 * @sk_max_ack_backlog: listen backlog set in listen()
210 * @sk_priority: %SO_PRIORITY setting
211 * @sk_type: socket type (%SOCK_STREAM, etc)
212 * @sk_protocol: which protocol this socket belongs in this network family
213 * @sk_peer_pid: &struct pid for this socket's peer
214 * @sk_peer_cred: %SO_PEERCRED setting
215 * @sk_rcvlowat: %SO_RCVLOWAT setting
216 * @sk_rcvtimeo: %SO_RCVTIMEO setting
217 * @sk_sndtimeo: %SO_SNDTIMEO setting
218 * @sk_rxhash: flow hash received from netif layer
219 * @sk_filter: socket filtering instructions
220 * @sk_protinfo: private area, net family specific, when not using slab
221 * @sk_timer: sock cleanup timer
222 * @sk_stamp: time stamp of last packet received
223 * @sk_socket: Identd and reporting IO signals
224 * @sk_user_data: RPC layer private data
225 * @sk_sndmsg_page: cached page for sendmsg
226 * @sk_sndmsg_off: cached offset for sendmsg
227 * @sk_send_head: front of stuff to transmit
228 * @sk_security: used by security modules
229 * @sk_mark: generic packet mark
230 * @sk_classid: this socket's cgroup classid
231 * @sk_write_pending: a write to stream socket waits to start
232 * @sk_state_change: callback to indicate change in the state of the sock
233 * @sk_data_ready: callback to indicate there is data to be processed
234 * @sk_write_space: callback to indicate there is bf sending space available
235 * @sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
236 * @sk_backlog_rcv: callback to process the backlog
237 * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
238 */
239struct sock {
240 /*
241 * Now struct inet_timewait_sock also uses sock_common, so please just
242 * don't add nothing before this first member (__sk_common) --acme
243 */
244 struct sock_common __sk_common;
245#define sk_node __sk_common.skc_node
246#define sk_nulls_node __sk_common.skc_nulls_node
247#define sk_refcnt __sk_common.skc_refcnt
248#define sk_tx_queue_mapping __sk_common.skc_tx_queue_mapping
249
250#define sk_dontcopy_begin __sk_common.skc_dontcopy_begin
251#define sk_dontcopy_end __sk_common.skc_dontcopy_end
252#define sk_hash __sk_common.skc_hash
253#define sk_family __sk_common.skc_family
254#define sk_state __sk_common.skc_state
255#define sk_reuse __sk_common.skc_reuse
256#define sk_bound_dev_if __sk_common.skc_bound_dev_if
257#define sk_bind_node __sk_common.skc_bind_node
258#define sk_prot __sk_common.skc_prot
259#define sk_net __sk_common.skc_net
260 socket_lock_t sk_lock;
261 struct sk_buff_head sk_receive_queue;
262 /*
263 * The backlog queue is special, it is always used with
264 * the per-socket spinlock held and requires low latency
265 * access. Therefore we special case it's implementation.
266 * Note : rmem_alloc is in this structure to fill a hole
267 * on 64bit arches, not because its logically part of
268 * backlog.
269 */
270 struct {
271 atomic_t rmem_alloc;
272 int len;
273 struct sk_buff *head;
274 struct sk_buff *tail;
275 } sk_backlog;
276#define sk_rmem_alloc sk_backlog.rmem_alloc
277 int sk_forward_alloc;
278#ifdef CONFIG_RPS
279 __u32 sk_rxhash;
280#endif
281 atomic_t sk_drops;
282 int sk_rcvbuf;
283
284 struct sk_filter __rcu *sk_filter;
285 struct socket_wq __rcu *sk_wq;
286
287#ifdef CONFIG_NET_DMA
288 struct sk_buff_head sk_async_wait_queue;
289#endif
290
291#ifdef CONFIG_XFRM
292 struct xfrm_policy *sk_policy[2];
293#endif
294 unsigned long sk_flags;
295 struct dst_entry *sk_dst_cache;
296 spinlock_t sk_dst_lock;
297 atomic_t sk_wmem_alloc;
298 atomic_t sk_omem_alloc;
299 int sk_sndbuf;
300 struct sk_buff_head sk_write_queue;
301 kmemcheck_bitfield_begin(flags);
302 unsigned int sk_shutdown : 2,
303 sk_no_check : 2,
304 sk_userlocks : 4,
305 sk_protocol : 8,
306 sk_type : 16;
307 kmemcheck_bitfield_end(flags);
308 int sk_wmem_queued;
309 gfp_t sk_allocation;
310 int sk_route_caps;
311 int sk_route_nocaps;
312 int sk_gso_type;
313 unsigned int sk_gso_max_size;
314 int sk_rcvlowat;
315 unsigned long sk_lingertime;
316 struct sk_buff_head sk_error_queue;
317 struct proto *sk_prot_creator;
318 rwlock_t sk_callback_lock;
319 int sk_err,
320 sk_err_soft;
321 unsigned short sk_ack_backlog;
322 unsigned short sk_max_ack_backlog;
323 __u32 sk_priority;
324 struct pid *sk_peer_pid;
325 const struct cred *sk_peer_cred;
326 long sk_rcvtimeo;
327 long sk_sndtimeo;
328 void *sk_protinfo;
329 struct timer_list sk_timer;
330 ktime_t sk_stamp;
331 struct socket *sk_socket;
332 void *sk_user_data;
333 struct page *sk_sndmsg_page;
334 struct sk_buff *sk_send_head;
335 __u32 sk_sndmsg_off;
336 int sk_write_pending;
337#ifdef CONFIG_SECURITY
338 void *sk_security;
339#endif
340 __u32 sk_mark;
341 u32 sk_classid;
342 void (*sk_state_change)(struct sock *sk);
343 void (*sk_data_ready)(struct sock *sk, int bytes);
344 void (*sk_write_space)(struct sock *sk);
345 void (*sk_error_report)(struct sock *sk);
346 int (*sk_backlog_rcv)(struct sock *sk,
347 struct sk_buff *skb);
348 void (*sk_destruct)(struct sock *sk);
349};
350
351/*
352 * Hashed lists helper routines
353 */
354static inline struct sock *sk_entry(const struct hlist_node *node)
355{
356 return hlist_entry(node, struct sock, sk_node);
357}
358
359static inline struct sock *__sk_head(const struct hlist_head *head)
360{
361 return hlist_entry(head->first, struct sock, sk_node);
362}
363
364static inline struct sock *sk_head(const struct hlist_head *head)
365{
366 return hlist_empty(head) ? NULL : __sk_head(head);
367}
368
369static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head)
370{
371 return hlist_nulls_entry(head->first, struct sock, sk_nulls_node);
372}
373
374static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head)
375{
376 return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head);
377}
378
379static inline struct sock *sk_next(const struct sock *sk)
380{
381 return sk->sk_node.next ?
382 hlist_entry(sk->sk_node.next, struct sock, sk_node) : NULL;
383}
384
385static inline struct sock *sk_nulls_next(const struct sock *sk)
386{
387 return (!is_a_nulls(sk->sk_nulls_node.next)) ?
388 hlist_nulls_entry(sk->sk_nulls_node.next,
389 struct sock, sk_nulls_node) :
390 NULL;
391}
392
393static inline int sk_unhashed(const struct sock *sk)
394{
395 return hlist_unhashed(&sk->sk_node);
396}
397
398static inline int sk_hashed(const struct sock *sk)
399{
400 return !sk_unhashed(sk);
401}
402
403static __inline__ void sk_node_init(struct hlist_node *node)
404{
405 node->pprev = NULL;
406}
407
408static __inline__ void sk_nulls_node_init(struct hlist_nulls_node *node)
409{
410 node->pprev = NULL;
411}
412
413static __inline__ void __sk_del_node(struct sock *sk)
414{
415 __hlist_del(&sk->sk_node);
416}
417
418/* NB: equivalent to hlist_del_init_rcu */
419static __inline__ int __sk_del_node_init(struct sock *sk)
420{
421 if (sk_hashed(sk)) {
422 __sk_del_node(sk);
423 sk_node_init(&sk->sk_node);
424 return 1;
425 }
426 return 0;
427}
428
429/* Grab socket reference count. This operation is valid only
430 when sk is ALREADY grabbed f.e. it is found in hash table
431 or a list and the lookup is made under lock preventing hash table
432 modifications.
433 */
434
435static inline void sock_hold(struct sock *sk)
436{
437 atomic_inc(&sk->sk_refcnt);
438}
439
440/* Ungrab socket in the context, which assumes that socket refcnt
441 cannot hit zero, f.e. it is true in context of any socketcall.
442 */
443static inline void __sock_put(struct sock *sk)
444{
445 atomic_dec(&sk->sk_refcnt);
446}
447
448static __inline__ int sk_del_node_init(struct sock *sk)
449{
450 int rc = __sk_del_node_init(sk);
451
452 if (rc) {
453 /* paranoid for a while -acme */
454 WARN_ON(atomic_read(&sk->sk_refcnt) == 1);
455 __sock_put(sk);
456 }
457 return rc;
458}
459#define sk_del_node_init_rcu(sk) sk_del_node_init(sk)
460
461static __inline__ int __sk_nulls_del_node_init_rcu(struct sock *sk)
462{
463 if (sk_hashed(sk)) {
464 hlist_nulls_del_init_rcu(&sk->sk_nulls_node);
465 return 1;
466 }
467 return 0;
468}
469
470static __inline__ int sk_nulls_del_node_init_rcu(struct sock *sk)
471{
472 int rc = __sk_nulls_del_node_init_rcu(sk);
473
474 if (rc) {
475 /* paranoid for a while -acme */
476 WARN_ON(atomic_read(&sk->sk_refcnt) == 1);
477 __sock_put(sk);
478 }
479 return rc;
480}
481
482static __inline__ void __sk_add_node(struct sock *sk, struct hlist_head *list)
483{
484 hlist_add_head(&sk->sk_node, list);
485}
486
487static __inline__ void sk_add_node(struct sock *sk, struct hlist_head *list)
488{
489 sock_hold(sk);
490 __sk_add_node(sk, list);
491}
492
493static __inline__ void sk_add_node_rcu(struct sock *sk, struct hlist_head *list)
494{
495 sock_hold(sk);
496 hlist_add_head_rcu(&sk->sk_node, list);
497}
498
499static __inline__ void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
500{
501 hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list);
502}
503
504static __inline__ void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
505{
506 sock_hold(sk);
507 __sk_nulls_add_node_rcu(sk, list);
508}
509
510static __inline__ void __sk_del_bind_node(struct sock *sk)
511{
512 __hlist_del(&sk->sk_bind_node);
513}
514
515static __inline__ void sk_add_bind_node(struct sock *sk,
516 struct hlist_head *list)
517{
518 hlist_add_head(&sk->sk_bind_node, list);
519}
520
521#define sk_for_each(__sk, node, list) \
522 hlist_for_each_entry(__sk, node, list, sk_node)
523#define sk_for_each_rcu(__sk, node, list) \
524 hlist_for_each_entry_rcu(__sk, node, list, sk_node)
525#define sk_nulls_for_each(__sk, node, list) \
526 hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)
527#define sk_nulls_for_each_rcu(__sk, node, list) \
528 hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)
529#define sk_for_each_from(__sk, node) \
530 if (__sk && ({ node = &(__sk)->sk_node; 1; })) \
531 hlist_for_each_entry_from(__sk, node, sk_node)
532#define sk_nulls_for_each_from(__sk, node) \
533 if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \
534 hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node)
535#define sk_for_each_safe(__sk, node, tmp, list) \
536 hlist_for_each_entry_safe(__sk, node, tmp, list, sk_node)
537#define sk_for_each_bound(__sk, node, list) \
538 hlist_for_each_entry(__sk, node, list, sk_bind_node)
539
540/* Sock flags */
541enum sock_flags {
542 SOCK_DEAD,
543 SOCK_DONE,
544 SOCK_URGINLINE,
545 SOCK_KEEPOPEN,
546 SOCK_LINGER,
547 SOCK_DESTROY,
548 SOCK_BROADCAST,
549 SOCK_TIMESTAMP,
550 SOCK_ZAPPED,
551 SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */
552 SOCK_DBG, /* %SO_DEBUG setting */
553 SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
554 SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */
555 SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
556 SOCK_QUEUE_SHRUNK, /* write queue has been shrunk recently */
557 SOCK_TIMESTAMPING_TX_HARDWARE, /* %SOF_TIMESTAMPING_TX_HARDWARE */
558 SOCK_TIMESTAMPING_TX_SOFTWARE, /* %SOF_TIMESTAMPING_TX_SOFTWARE */
559 SOCK_TIMESTAMPING_RX_HARDWARE, /* %SOF_TIMESTAMPING_RX_HARDWARE */
560 SOCK_TIMESTAMPING_RX_SOFTWARE, /* %SOF_TIMESTAMPING_RX_SOFTWARE */
561 SOCK_TIMESTAMPING_SOFTWARE, /* %SOF_TIMESTAMPING_SOFTWARE */
562 SOCK_TIMESTAMPING_RAW_HARDWARE, /* %SOF_TIMESTAMPING_RAW_HARDWARE */
563 SOCK_TIMESTAMPING_SYS_HARDWARE, /* %SOF_TIMESTAMPING_SYS_HARDWARE */
564 SOCK_FASYNC, /* fasync() active */
565 SOCK_RXQ_OVFL,
566 SOCK_ZEROCOPY, /* buffers from userspace */
567};
568
569static inline void sock_copy_flags(struct sock *nsk, struct sock *osk)
570{
571 nsk->sk_flags = osk->sk_flags;
572}
573
574static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
575{
576 __set_bit(flag, &sk->sk_flags);
577}
578
579static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag)
580{
581 __clear_bit(flag, &sk->sk_flags);
582}
583
584static inline int sock_flag(struct sock *sk, enum sock_flags flag)
585{
586 return test_bit(flag, &sk->sk_flags);
587}
588
589static inline void sk_acceptq_removed(struct sock *sk)
590{
591 sk->sk_ack_backlog--;
592}
593
594static inline void sk_acceptq_added(struct sock *sk)
595{
596 sk->sk_ack_backlog++;
597}
598
599static inline int sk_acceptq_is_full(struct sock *sk)
600{
601 return sk->sk_ack_backlog > sk->sk_max_ack_backlog;
602}
603
604/*
605 * Compute minimal free write space needed to queue new packets.
606 */
607static inline int sk_stream_min_wspace(struct sock *sk)
608{
609 return sk->sk_wmem_queued >> 1;
610}
611
612static inline int sk_stream_wspace(struct sock *sk)
613{
614 return sk->sk_sndbuf - sk->sk_wmem_queued;
615}
616
617extern void sk_stream_write_space(struct sock *sk);
618
619static inline int sk_stream_memory_free(struct sock *sk)
620{
621 return sk->sk_wmem_queued < sk->sk_sndbuf;
622}
623
624/* OOB backlog add */
625static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
626{
627 /* dont let skb dst not refcounted, we are going to leave rcu lock */
628 skb_dst_force(skb);
629
630 if (!sk->sk_backlog.tail)
631 sk->sk_backlog.head = skb;
632 else
633 sk->sk_backlog.tail->next = skb;
634
635 sk->sk_backlog.tail = skb;
636 skb->next = NULL;
637}
638
639/*
640 * Take into account size of receive queue and backlog queue
641 */
642static inline bool sk_rcvqueues_full(const struct sock *sk, const struct sk_buff *skb)
643{
644 unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc);
645
646 return qsize + skb->truesize > sk->sk_rcvbuf;
647}
648
649/* The per-socket spinlock must be held here. */
650static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb)
651{
652 if (sk_rcvqueues_full(sk, skb))
653 return -ENOBUFS;
654
655 __sk_add_backlog(sk, skb);
656 sk->sk_backlog.len += skb->truesize;
657 return 0;
658}
659
660static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
661{
662 return sk->sk_backlog_rcv(sk, skb);
663}
664
665static inline void sock_rps_record_flow(const struct sock *sk)
666{
667#ifdef CONFIG_RPS
668 struct rps_sock_flow_table *sock_flow_table;
669
670 rcu_read_lock();
671 sock_flow_table = rcu_dereference(rps_sock_flow_table);
672 rps_record_sock_flow(sock_flow_table, sk->sk_rxhash);
673 rcu_read_unlock();
674#endif
675}
676
677static inline void sock_rps_reset_flow(const struct sock *sk)
678{
679#ifdef CONFIG_RPS
680 struct rps_sock_flow_table *sock_flow_table;
681
682 rcu_read_lock();
683 sock_flow_table = rcu_dereference(rps_sock_flow_table);
684 rps_reset_sock_flow(sock_flow_table, sk->sk_rxhash);
685 rcu_read_unlock();
686#endif
687}
688
689static inline void sock_rps_save_rxhash(struct sock *sk, u32 rxhash)
690{
691#ifdef CONFIG_RPS
692 if (unlikely(sk->sk_rxhash != rxhash)) {
693 sock_rps_reset_flow(sk);
694 sk->sk_rxhash = rxhash;
695 }
696#endif
697}
698
699#define sk_wait_event(__sk, __timeo, __condition) \
700 ({ int __rc; \
701 release_sock(__sk); \
702 __rc = __condition; \
703 if (!__rc) { \
704 *(__timeo) = schedule_timeout(*(__timeo)); \
705 } \
706 lock_sock(__sk); \
707 __rc = __condition; \
708 __rc; \
709 })
710
711extern int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
712extern int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
713extern void sk_stream_wait_close(struct sock *sk, long timeo_p);
714extern int sk_stream_error(struct sock *sk, int flags, int err);
715extern void sk_stream_kill_queues(struct sock *sk);
716
717extern int sk_wait_data(struct sock *sk, long *timeo);
718
719struct request_sock_ops;
720struct timewait_sock_ops;
721struct inet_hashinfo;
722struct raw_hashinfo;
723
724/* Networking protocol blocks we attach to sockets.
725 * socket layer -> transport layer interface
726 * transport -> network interface is defined by struct inet_proto
727 */
728struct proto {
729 void (*close)(struct sock *sk,
730 long timeout);
731 int (*connect)(struct sock *sk,
732 struct sockaddr *uaddr,
733 int addr_len);
734 int (*disconnect)(struct sock *sk, int flags);
735
736 struct sock * (*accept) (struct sock *sk, int flags, int *err);
737
738 int (*ioctl)(struct sock *sk, int cmd,
739 unsigned long arg);
740 int (*init)(struct sock *sk);
741 void (*destroy)(struct sock *sk);
742 void (*shutdown)(struct sock *sk, int how);
743 int (*setsockopt)(struct sock *sk, int level,
744 int optname, char __user *optval,
745 unsigned int optlen);
746 int (*getsockopt)(struct sock *sk, int level,
747 int optname, char __user *optval,
748 int __user *option);
749#ifdef CONFIG_COMPAT
750 int (*compat_setsockopt)(struct sock *sk,
751 int level,
752 int optname, char __user *optval,
753 unsigned int optlen);
754 int (*compat_getsockopt)(struct sock *sk,
755 int level,
756 int optname, char __user *optval,
757 int __user *option);
758 int (*compat_ioctl)(struct sock *sk,
759 unsigned int cmd, unsigned long arg);
760#endif
761 int (*sendmsg)(struct kiocb *iocb, struct sock *sk,
762 struct msghdr *msg, size_t len);
763 int (*recvmsg)(struct kiocb *iocb, struct sock *sk,
764 struct msghdr *msg,
765 size_t len, int noblock, int flags,
766 int *addr_len);
767 int (*sendpage)(struct sock *sk, struct page *page,
768 int offset, size_t size, int flags);
769 int (*bind)(struct sock *sk,
770 struct sockaddr *uaddr, int addr_len);
771
772 int (*backlog_rcv) (struct sock *sk,
773 struct sk_buff *skb);
774
775 /* Keeping track of sk's, looking them up, and port selection methods. */
776 void (*hash)(struct sock *sk);
777 void (*unhash)(struct sock *sk);
778 void (*rehash)(struct sock *sk);
779 int (*get_port)(struct sock *sk, unsigned short snum);
780 void (*clear_sk)(struct sock *sk, int size);
781
782 /* Keeping track of sockets in use */
783#ifdef CONFIG_PROC_FS
784 unsigned int inuse_idx;
785#endif
786
787 /* Memory pressure */
788 void (*enter_memory_pressure)(struct sock *sk);
789 atomic_long_t *memory_allocated; /* Current allocated memory. */
790 struct percpu_counter *sockets_allocated; /* Current number of sockets. */
791 /*
792 * Pressure flag: try to collapse.
793 * Technical note: it is used by multiple contexts non atomically.
794 * All the __sk_mem_schedule() is of this nature: accounting
795 * is strict, actions are advisory and have some latency.
796 */
797 int *memory_pressure;
798 long *sysctl_mem;
799 int *sysctl_wmem;
800 int *sysctl_rmem;
801 int max_header;
802 bool no_autobind;
803
804 struct kmem_cache *slab;
805 unsigned int obj_size;
806 int slab_flags;
807
808 struct percpu_counter *orphan_count;
809
810 struct request_sock_ops *rsk_prot;
811 struct timewait_sock_ops *twsk_prot;
812
813 union {
814 struct inet_hashinfo *hashinfo;
815 struct udp_table *udp_table;
816 struct raw_hashinfo *raw_hash;
817 } h;
818
819 struct module *owner;
820
821 char name[32];
822
823 struct list_head node;
824#ifdef SOCK_REFCNT_DEBUG
825 atomic_t socks;
826#endif
827};
828
829extern int proto_register(struct proto *prot, int alloc_slab);
830extern void proto_unregister(struct proto *prot);
831
832#ifdef SOCK_REFCNT_DEBUG
833static inline void sk_refcnt_debug_inc(struct sock *sk)
834{
835 atomic_inc(&sk->sk_prot->socks);
836}
837
838static inline void sk_refcnt_debug_dec(struct sock *sk)
839{
840 atomic_dec(&sk->sk_prot->socks);
841 printk(KERN_DEBUG "%s socket %p released, %d are still alive\n",
842 sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks));
843}
844
845static inline void sk_refcnt_debug_release(const struct sock *sk)
846{
847 if (atomic_read(&sk->sk_refcnt) != 1)
848 printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n",
849 sk->sk_prot->name, sk, atomic_read(&sk->sk_refcnt));
850}
851#else /* SOCK_REFCNT_DEBUG */
852#define sk_refcnt_debug_inc(sk) do { } while (0)
853#define sk_refcnt_debug_dec(sk) do { } while (0)
854#define sk_refcnt_debug_release(sk) do { } while (0)
855#endif /* SOCK_REFCNT_DEBUG */
856
857
858#ifdef CONFIG_PROC_FS
859/* Called with local bh disabled */
860extern void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc);
861extern int sock_prot_inuse_get(struct net *net, struct proto *proto);
862#else
863static void inline sock_prot_inuse_add(struct net *net, struct proto *prot,
864 int inc)
865{
866}
867#endif
868
869
870/* With per-bucket locks this operation is not-atomic, so that
871 * this version is not worse.
872 */
873static inline void __sk_prot_rehash(struct sock *sk)
874{
875 sk->sk_prot->unhash(sk);
876 sk->sk_prot->hash(sk);
877}
878
879void sk_prot_clear_portaddr_nulls(struct sock *sk, int size);
880
881/* About 10 seconds */
882#define SOCK_DESTROY_TIME (10*HZ)
883
884/* Sockets 0-1023 can't be bound to unless you are superuser */
885#define PROT_SOCK 1024
886
887#define SHUTDOWN_MASK 3
888#define RCV_SHUTDOWN 1
889#define SEND_SHUTDOWN 2
890
891#define SOCK_SNDBUF_LOCK 1
892#define SOCK_RCVBUF_LOCK 2
893#define SOCK_BINDADDR_LOCK 4
894#define SOCK_BINDPORT_LOCK 8
895
896/* sock_iocb: used to kick off async processing of socket ios */
897struct sock_iocb {
898 struct list_head list;
899
900 int flags;
901 int size;
902 struct socket *sock;
903 struct sock *sk;
904 struct scm_cookie *scm;
905 struct msghdr *msg, async_msg;
906 struct kiocb *kiocb;
907};
908
909static inline struct sock_iocb *kiocb_to_siocb(struct kiocb *iocb)
910{
911 return (struct sock_iocb *)iocb->private;
912}
913
914static inline struct kiocb *siocb_to_kiocb(struct sock_iocb *si)
915{
916 return si->kiocb;
917}
918
919struct socket_alloc {
920 struct socket socket;
921 struct inode vfs_inode;
922};
923
924static inline struct socket *SOCKET_I(struct inode *inode)
925{
926 return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
927}
928
929static inline struct inode *SOCK_INODE(struct socket *socket)
930{
931 return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
932}
933
934/*
935 * Functions for memory accounting
936 */
937extern int __sk_mem_schedule(struct sock *sk, int size, int kind);
938extern void __sk_mem_reclaim(struct sock *sk);
939
940#define SK_MEM_QUANTUM ((int)PAGE_SIZE)
941#define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM)
942#define SK_MEM_SEND 0
943#define SK_MEM_RECV 1
944
945static inline int sk_mem_pages(int amt)
946{
947 return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT;
948}
949
950static inline int sk_has_account(struct sock *sk)
951{
952 /* return true if protocol supports memory accounting */
953 return !!sk->sk_prot->memory_allocated;
954}
955
956static inline int sk_wmem_schedule(struct sock *sk, int size)
957{
958 if (!sk_has_account(sk))
959 return 1;
960 return size <= sk->sk_forward_alloc ||
961 __sk_mem_schedule(sk, size, SK_MEM_SEND);
962}
963
964static inline int sk_rmem_schedule(struct sock *sk, int size)
965{
966 if (!sk_has_account(sk))
967 return 1;
968 return size <= sk->sk_forward_alloc ||
969 __sk_mem_schedule(sk, size, SK_MEM_RECV);
970}
971
972static inline void sk_mem_reclaim(struct sock *sk)
973{
974 if (!sk_has_account(sk))
975 return;
976 if (sk->sk_forward_alloc >= SK_MEM_QUANTUM)
977 __sk_mem_reclaim(sk);
978}
979
980static inline void sk_mem_reclaim_partial(struct sock *sk)
981{
982 if (!sk_has_account(sk))
983 return;
984 if (sk->sk_forward_alloc > SK_MEM_QUANTUM)
985 __sk_mem_reclaim(sk);
986}
987
988static inline void sk_mem_charge(struct sock *sk, int size)
989{
990 if (!sk_has_account(sk))
991 return;
992 sk->sk_forward_alloc -= size;
993}
994
995static inline void sk_mem_uncharge(struct sock *sk, int size)
996{
997 if (!sk_has_account(sk))
998 return;
999 sk->sk_forward_alloc += size;
1000}
1001
1002static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb)
1003{
1004 sock_set_flag(sk, SOCK_QUEUE_SHRUNK);
1005 sk->sk_wmem_queued -= skb->truesize;
1006 sk_mem_uncharge(sk, skb->truesize);
1007 __kfree_skb(skb);
1008}
1009
1010/* Used by processes to "lock" a socket state, so that
1011 * interrupts and bottom half handlers won't change it
1012 * from under us. It essentially blocks any incoming
1013 * packets, so that we won't get any new data or any
1014 * packets that change the state of the socket.
1015 *
1016 * While locked, BH processing will add new packets to
1017 * the backlog queue. This queue is processed by the
1018 * owner of the socket lock right before it is released.
1019 *
1020 * Since ~2.3.5 it is also exclusive sleep lock serializing
1021 * accesses from user process context.
1022 */
1023#define sock_owned_by_user(sk) ((sk)->sk_lock.owned)
1024
1025/*
1026 * Macro so as to not evaluate some arguments when
1027 * lockdep is not enabled.
1028 *
1029 * Mark both the sk_lock and the sk_lock.slock as a
1030 * per-address-family lock class.
1031 */
1032#define sock_lock_init_class_and_name(sk, sname, skey, name, key) \
1033do { \
1034 sk->sk_lock.owned = 0; \
1035 init_waitqueue_head(&sk->sk_lock.wq); \
1036 spin_lock_init(&(sk)->sk_lock.slock); \
1037 debug_check_no_locks_freed((void *)&(sk)->sk_lock, \
1038 sizeof((sk)->sk_lock)); \
1039 lockdep_set_class_and_name(&(sk)->sk_lock.slock, \
1040 (skey), (sname)); \
1041 lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \
1042} while (0)
1043
1044extern void lock_sock_nested(struct sock *sk, int subclass);
1045
1046static inline void lock_sock(struct sock *sk)
1047{
1048 lock_sock_nested(sk, 0);
1049}
1050
1051extern void release_sock(struct sock *sk);
1052
1053/* BH context may only use the following locking interface. */
1054#define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock))
1055#define bh_lock_sock_nested(__sk) \
1056 spin_lock_nested(&((__sk)->sk_lock.slock), \
1057 SINGLE_DEPTH_NESTING)
1058#define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock))
1059
1060extern bool lock_sock_fast(struct sock *sk);
1061/**
1062 * unlock_sock_fast - complement of lock_sock_fast
1063 * @sk: socket
1064 * @slow: slow mode
1065 *
1066 * fast unlock socket for user context.
1067 * If slow mode is on, we call regular release_sock()
1068 */
1069static inline void unlock_sock_fast(struct sock *sk, bool slow)
1070{
1071 if (slow)
1072 release_sock(sk);
1073 else
1074 spin_unlock_bh(&sk->sk_lock.slock);
1075}
1076
1077
1078extern struct sock *sk_alloc(struct net *net, int family,
1079 gfp_t priority,
1080 struct proto *prot);
1081extern void sk_free(struct sock *sk);
1082extern void sk_release_kernel(struct sock *sk);
1083extern struct sock *sk_clone(const struct sock *sk,
1084 const gfp_t priority);
1085
1086extern struct sk_buff *sock_wmalloc(struct sock *sk,
1087 unsigned long size, int force,
1088 gfp_t priority);
1089extern struct sk_buff *sock_rmalloc(struct sock *sk,
1090 unsigned long size, int force,
1091 gfp_t priority);
1092extern void sock_wfree(struct sk_buff *skb);
1093extern void sock_rfree(struct sk_buff *skb);
1094
1095extern int sock_setsockopt(struct socket *sock, int level,
1096 int op, char __user *optval,
1097 unsigned int optlen);
1098
1099extern int sock_getsockopt(struct socket *sock, int level,
1100 int op, char __user *optval,
1101 int __user *optlen);
1102extern struct sk_buff *sock_alloc_send_skb(struct sock *sk,
1103 unsigned long size,
1104 int noblock,
1105 int *errcode);
1106extern struct sk_buff *sock_alloc_send_pskb(struct sock *sk,
1107 unsigned long header_len,
1108 unsigned long data_len,
1109 int noblock,
1110 int *errcode);
1111extern void *sock_kmalloc(struct sock *sk, int size,
1112 gfp_t priority);
1113extern void sock_kfree_s(struct sock *sk, void *mem, int size);
1114extern void sk_send_sigurg(struct sock *sk);
1115
1116#ifdef CONFIG_CGROUPS
1117extern void sock_update_classid(struct sock *sk);
1118#else
1119static inline void sock_update_classid(struct sock *sk)
1120{
1121}
1122#endif
1123
1124/*
1125 * Functions to fill in entries in struct proto_ops when a protocol
1126 * does not implement a particular function.
1127 */
1128extern int sock_no_bind(struct socket *,
1129 struct sockaddr *, int);
1130extern int sock_no_connect(struct socket *,
1131 struct sockaddr *, int, int);
1132extern int sock_no_socketpair(struct socket *,
1133 struct socket *);
1134extern int sock_no_accept(struct socket *,
1135 struct socket *, int);
1136extern int sock_no_getname(struct socket *,
1137 struct sockaddr *, int *, int);
1138extern unsigned int sock_no_poll(struct file *, struct socket *,
1139 struct poll_table_struct *);
1140extern int sock_no_ioctl(struct socket *, unsigned int,
1141 unsigned long);
1142extern int sock_no_listen(struct socket *, int);
1143extern int sock_no_shutdown(struct socket *, int);
1144extern int sock_no_getsockopt(struct socket *, int , int,
1145 char __user *, int __user *);
1146extern int sock_no_setsockopt(struct socket *, int, int,
1147 char __user *, unsigned int);
1148extern int sock_no_sendmsg(struct kiocb *, struct socket *,
1149 struct msghdr *, size_t);
1150extern int sock_no_recvmsg(struct kiocb *, struct socket *,
1151 struct msghdr *, size_t, int);
1152extern int sock_no_mmap(struct file *file,
1153 struct socket *sock,
1154 struct vm_area_struct *vma);
1155extern ssize_t sock_no_sendpage(struct socket *sock,
1156 struct page *page,
1157 int offset, size_t size,
1158 int flags);
1159
1160/*
1161 * Functions to fill in entries in struct proto_ops when a protocol
1162 * uses the inet style.
1163 */
1164extern int sock_common_getsockopt(struct socket *sock, int level, int optname,
1165 char __user *optval, int __user *optlen);
1166extern int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock,
1167 struct msghdr *msg, size_t size, int flags);
1168extern int sock_common_setsockopt(struct socket *sock, int level, int optname,
1169 char __user *optval, unsigned int optlen);
1170extern int compat_sock_common_getsockopt(struct socket *sock, int level,
1171 int optname, char __user *optval, int __user *optlen);
1172extern int compat_sock_common_setsockopt(struct socket *sock, int level,
1173 int optname, char __user *optval, unsigned int optlen);
1174
1175extern void sk_common_release(struct sock *sk);
1176
1177/*
1178 * Default socket callbacks and setup code
1179 */
1180
1181/* Initialise core socket variables */
1182extern void sock_init_data(struct socket *sock, struct sock *sk);
1183
1184extern void sk_filter_release_rcu(struct rcu_head *rcu);
1185
1186/**
1187 * sk_filter_release - release a socket filter
1188 * @fp: filter to remove
1189 *
1190 * Remove a filter from a socket and release its resources.
1191 */
1192
1193static inline void sk_filter_release(struct sk_filter *fp)
1194{
1195 if (atomic_dec_and_test(&fp->refcnt))
1196 call_rcu(&fp->rcu, sk_filter_release_rcu);
1197}
1198
1199static inline void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp)
1200{
1201 unsigned int size = sk_filter_len(fp);
1202
1203 atomic_sub(size, &sk->sk_omem_alloc);
1204 sk_filter_release(fp);
1205}
1206
1207static inline void sk_filter_charge(struct sock *sk, struct sk_filter *fp)
1208{
1209 atomic_inc(&fp->refcnt);
1210 atomic_add(sk_filter_len(fp), &sk->sk_omem_alloc);
1211}
1212
1213/*
1214 * Socket reference counting postulates.
1215 *
1216 * * Each user of socket SHOULD hold a reference count.
1217 * * Each access point to socket (an hash table bucket, reference from a list,
1218 * running timer, skb in flight MUST hold a reference count.
1219 * * When reference count hits 0, it means it will never increase back.
1220 * * When reference count hits 0, it means that no references from
1221 * outside exist to this socket and current process on current CPU
1222 * is last user and may/should destroy this socket.
1223 * * sk_free is called from any context: process, BH, IRQ. When
1224 * it is called, socket has no references from outside -> sk_free
1225 * may release descendant resources allocated by the socket, but
1226 * to the time when it is called, socket is NOT referenced by any
1227 * hash tables, lists etc.
1228 * * Packets, delivered from outside (from network or from another process)
1229 * and enqueued on receive/error queues SHOULD NOT grab reference count,
1230 * when they sit in queue. Otherwise, packets will leak to hole, when
1231 * socket is looked up by one cpu and unhasing is made by another CPU.
1232 * It is true for udp/raw, netlink (leak to receive and error queues), tcp
1233 * (leak to backlog). Packet socket does all the processing inside
1234 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
1235 * use separate SMP lock, so that they are prone too.
1236 */
1237
1238/* Ungrab socket and destroy it, if it was the last reference. */
1239static inline void sock_put(struct sock *sk)
1240{
1241 if (atomic_dec_and_test(&sk->sk_refcnt))
1242 sk_free(sk);
1243}
1244
1245extern int sk_receive_skb(struct sock *sk, struct sk_buff *skb,
1246 const int nested);
1247
1248static inline void sk_tx_queue_set(struct sock *sk, int tx_queue)
1249{
1250 sk->sk_tx_queue_mapping = tx_queue;
1251}
1252
1253static inline void sk_tx_queue_clear(struct sock *sk)
1254{
1255 sk->sk_tx_queue_mapping = -1;
1256}
1257
1258static inline int sk_tx_queue_get(const struct sock *sk)
1259{
1260 return sk ? sk->sk_tx_queue_mapping : -1;
1261}
1262
1263static inline void sk_set_socket(struct sock *sk, struct socket *sock)
1264{
1265 sk_tx_queue_clear(sk);
1266 sk->sk_socket = sock;
1267}
1268
1269static inline wait_queue_head_t *sk_sleep(struct sock *sk)
1270{
1271 BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0);
1272 return &rcu_dereference_raw(sk->sk_wq)->wait;
1273}
1274/* Detach socket from process context.
1275 * Announce socket dead, detach it from wait queue and inode.
1276 * Note that parent inode held reference count on this struct sock,
1277 * we do not release it in this function, because protocol
1278 * probably wants some additional cleanups or even continuing
1279 * to work with this socket (TCP).
1280 */
1281static inline void sock_orphan(struct sock *sk)
1282{
1283 write_lock_bh(&sk->sk_callback_lock);
1284 sock_set_flag(sk, SOCK_DEAD);
1285 sk_set_socket(sk, NULL);
1286 sk->sk_wq = NULL;
1287 write_unlock_bh(&sk->sk_callback_lock);
1288}
1289
1290static inline void sock_graft(struct sock *sk, struct socket *parent)
1291{
1292 write_lock_bh(&sk->sk_callback_lock);
1293 sk->sk_wq = parent->wq;
1294 parent->sk = sk;
1295 sk_set_socket(sk, parent);
1296 security_sock_graft(sk, parent);
1297 write_unlock_bh(&sk->sk_callback_lock);
1298}
1299
1300extern int sock_i_uid(struct sock *sk);
1301extern unsigned long sock_i_ino(struct sock *sk);
1302
1303static inline struct dst_entry *
1304__sk_dst_get(struct sock *sk)
1305{
1306 return rcu_dereference_check(sk->sk_dst_cache, sock_owned_by_user(sk) ||
1307 lockdep_is_held(&sk->sk_lock.slock));
1308}
1309
1310static inline struct dst_entry *
1311sk_dst_get(struct sock *sk)
1312{
1313 struct dst_entry *dst;
1314
1315 rcu_read_lock();
1316 dst = rcu_dereference(sk->sk_dst_cache);
1317 if (dst)
1318 dst_hold(dst);
1319 rcu_read_unlock();
1320 return dst;
1321}
1322
1323extern void sk_reset_txq(struct sock *sk);
1324
1325static inline void dst_negative_advice(struct sock *sk)
1326{
1327 struct dst_entry *ndst, *dst = __sk_dst_get(sk);
1328
1329 if (dst && dst->ops->negative_advice) {
1330 ndst = dst->ops->negative_advice(dst);
1331
1332 if (ndst != dst) {
1333 rcu_assign_pointer(sk->sk_dst_cache, ndst);
1334 sk_reset_txq(sk);
1335 }
1336 }
1337}
1338
1339static inline void
1340__sk_dst_set(struct sock *sk, struct dst_entry *dst)
1341{
1342 struct dst_entry *old_dst;
1343
1344 sk_tx_queue_clear(sk);
1345 /*
1346 * This can be called while sk is owned by the caller only,
1347 * with no state that can be checked in a rcu_dereference_check() cond
1348 */
1349 old_dst = rcu_dereference_raw(sk->sk_dst_cache);
1350 rcu_assign_pointer(sk->sk_dst_cache, dst);
1351 dst_release(old_dst);
1352}
1353
1354static inline void
1355sk_dst_set(struct sock *sk, struct dst_entry *dst)
1356{
1357 spin_lock(&sk->sk_dst_lock);
1358 __sk_dst_set(sk, dst);
1359 spin_unlock(&sk->sk_dst_lock);
1360}
1361
1362static inline void
1363__sk_dst_reset(struct sock *sk)
1364{
1365 __sk_dst_set(sk, NULL);
1366}
1367
1368static inline void
1369sk_dst_reset(struct sock *sk)
1370{
1371 spin_lock(&sk->sk_dst_lock);
1372 __sk_dst_reset(sk);
1373 spin_unlock(&sk->sk_dst_lock);
1374}
1375
1376extern struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
1377
1378extern struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
1379
1380static inline int sk_can_gso(const struct sock *sk)
1381{
1382 return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type);
1383}
1384
1385extern void sk_setup_caps(struct sock *sk, struct dst_entry *dst);
1386
1387static inline void sk_nocaps_add(struct sock *sk, int flags)
1388{
1389 sk->sk_route_nocaps |= flags;
1390 sk->sk_route_caps &= ~flags;
1391}
1392
1393static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
1394 char __user *from, char *to,
1395 int copy, int offset)
1396{
1397 if (skb->ip_summed == CHECKSUM_NONE) {
1398 int err = 0;
1399 __wsum csum = csum_and_copy_from_user(from, to, copy, 0, &err);
1400 if (err)
1401 return err;
1402 skb->csum = csum_block_add(skb->csum, csum, offset);
1403 } else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
1404 if (!access_ok(VERIFY_READ, from, copy) ||
1405 __copy_from_user_nocache(to, from, copy))
1406 return -EFAULT;
1407 } else if (copy_from_user(to, from, copy))
1408 return -EFAULT;
1409
1410 return 0;
1411}
1412
1413static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
1414 char __user *from, int copy)
1415{
1416 int err, offset = skb->len;
1417
1418 err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy),
1419 copy, offset);
1420 if (err)
1421 __skb_trim(skb, offset);
1422
1423 return err;
1424}
1425
1426static inline int skb_copy_to_page_nocache(struct sock *sk, char __user *from,
1427 struct sk_buff *skb,
1428 struct page *page,
1429 int off, int copy)
1430{
1431 int err;
1432
1433 err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off,
1434 copy, skb->len);
1435 if (err)
1436 return err;
1437
1438 skb->len += copy;
1439 skb->data_len += copy;
1440 skb->truesize += copy;
1441 sk->sk_wmem_queued += copy;
1442 sk_mem_charge(sk, copy);
1443 return 0;
1444}
1445
1446static inline int skb_copy_to_page(struct sock *sk, char __user *from,
1447 struct sk_buff *skb, struct page *page,
1448 int off, int copy)
1449{
1450 if (skb->ip_summed == CHECKSUM_NONE) {
1451 int err = 0;
1452 __wsum csum = csum_and_copy_from_user(from,
1453 page_address(page) + off,
1454 copy, 0, &err);
1455 if (err)
1456 return err;
1457 skb->csum = csum_block_add(skb->csum, csum, skb->len);
1458 } else if (copy_from_user(page_address(page) + off, from, copy))
1459 return -EFAULT;
1460
1461 skb->len += copy;
1462 skb->data_len += copy;
1463 skb->truesize += copy;
1464 sk->sk_wmem_queued += copy;
1465 sk_mem_charge(sk, copy);
1466 return 0;
1467}
1468
1469/**
1470 * sk_wmem_alloc_get - returns write allocations
1471 * @sk: socket
1472 *
1473 * Returns sk_wmem_alloc minus initial offset of one
1474 */
1475static inline int sk_wmem_alloc_get(const struct sock *sk)
1476{
1477 return atomic_read(&sk->sk_wmem_alloc) - 1;
1478}
1479
1480/**
1481 * sk_rmem_alloc_get - returns read allocations
1482 * @sk: socket
1483 *
1484 * Returns sk_rmem_alloc
1485 */
1486static inline int sk_rmem_alloc_get(const struct sock *sk)
1487{
1488 return atomic_read(&sk->sk_rmem_alloc);
1489}
1490
1491/**
1492 * sk_has_allocations - check if allocations are outstanding
1493 * @sk: socket
1494 *
1495 * Returns true if socket has write or read allocations
1496 */
1497static inline int sk_has_allocations(const struct sock *sk)
1498{
1499 return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk);
1500}
1501
1502/**
1503 * wq_has_sleeper - check if there are any waiting processes
1504 * @wq: struct socket_wq
1505 *
1506 * Returns true if socket_wq has waiting processes
1507 *
1508 * The purpose of the wq_has_sleeper and sock_poll_wait is to wrap the memory
1509 * barrier call. They were added due to the race found within the tcp code.
1510 *
1511 * Consider following tcp code paths:
1512 *
1513 * CPU1 CPU2
1514 *
1515 * sys_select receive packet
1516 * ... ...
1517 * __add_wait_queue update tp->rcv_nxt
1518 * ... ...
1519 * tp->rcv_nxt check sock_def_readable
1520 * ... {
1521 * schedule rcu_read_lock();
1522 * wq = rcu_dereference(sk->sk_wq);
1523 * if (wq && waitqueue_active(&wq->wait))
1524 * wake_up_interruptible(&wq->wait)
1525 * ...
1526 * }
1527 *
1528 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
1529 * in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1
1530 * could then endup calling schedule and sleep forever if there are no more
1531 * data on the socket.
1532 *
1533 */
1534static inline bool wq_has_sleeper(struct socket_wq *wq)
1535{
1536
1537 /*
1538 * We need to be sure we are in sync with the
1539 * add_wait_queue modifications to the wait queue.
1540 *
1541 * This memory barrier is paired in the sock_poll_wait.
1542 */
1543 smp_mb();
1544 return wq && waitqueue_active(&wq->wait);
1545}
1546
1547/**
1548 * sock_poll_wait - place memory barrier behind the poll_wait call.
1549 * @filp: file
1550 * @wait_address: socket wait queue
1551 * @p: poll_table
1552 *
1553 * See the comments in the wq_has_sleeper function.
1554 */
1555static inline void sock_poll_wait(struct file *filp,
1556 wait_queue_head_t *wait_address, poll_table *p)
1557{
1558 if (p && wait_address) {
1559 poll_wait(filp, wait_address, p);
1560 /*
1561 * We need to be sure we are in sync with the
1562 * socket flags modification.
1563 *
1564 * This memory barrier is paired in the wq_has_sleeper.
1565 */
1566 smp_mb();
1567 }
1568}
1569
1570/*
1571 * Queue a received datagram if it will fit. Stream and sequenced
1572 * protocols can't normally use this as they need to fit buffers in
1573 * and play with them.
1574 *
1575 * Inlined as it's very short and called for pretty much every
1576 * packet ever received.
1577 */
1578
1579static inline void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
1580{
1581 skb_orphan(skb);
1582 skb->sk = sk;
1583 skb->destructor = sock_wfree;
1584 /*
1585 * We used to take a refcount on sk, but following operation
1586 * is enough to guarantee sk_free() wont free this sock until
1587 * all in-flight packets are completed
1588 */
1589 atomic_add(skb->truesize, &sk->sk_wmem_alloc);
1590}
1591
1592static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
1593{
1594 skb_orphan(skb);
1595 skb->sk = sk;
1596 skb->destructor = sock_rfree;
1597 atomic_add(skb->truesize, &sk->sk_rmem_alloc);
1598 sk_mem_charge(sk, skb->truesize);
1599}
1600
1601extern void sk_reset_timer(struct sock *sk, struct timer_list* timer,
1602 unsigned long expires);
1603
1604extern void sk_stop_timer(struct sock *sk, struct timer_list* timer);
1605
1606extern int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
1607
1608extern int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
1609
1610/*
1611 * Recover an error report and clear atomically
1612 */
1613
1614static inline int sock_error(struct sock *sk)
1615{
1616 int err;
1617 if (likely(!sk->sk_err))
1618 return 0;
1619 err = xchg(&sk->sk_err, 0);
1620 return -err;
1621}
1622
1623static inline unsigned long sock_wspace(struct sock *sk)
1624{
1625 int amt = 0;
1626
1627 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
1628 amt = sk->sk_sndbuf - atomic_read(&sk->sk_wmem_alloc);
1629 if (amt < 0)
1630 amt = 0;
1631 }
1632 return amt;
1633}
1634
1635static inline void sk_wake_async(struct sock *sk, int how, int band)
1636{
1637 if (sock_flag(sk, SOCK_FASYNC))
1638 sock_wake_async(sk->sk_socket, how, band);
1639}
1640
1641#define SOCK_MIN_SNDBUF 2048
1642/*
1643 * Since sk_rmem_alloc sums skb->truesize, even a small frame might need
1644 * sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak
1645 */
1646#define SOCK_MIN_RCVBUF (2048 + sizeof(struct sk_buff))
1647
1648static inline void sk_stream_moderate_sndbuf(struct sock *sk)
1649{
1650 if (!(sk->sk_userlocks & SOCK_SNDBUF_LOCK)) {
1651 sk->sk_sndbuf = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
1652 sk->sk_sndbuf = max(sk->sk_sndbuf, SOCK_MIN_SNDBUF);
1653 }
1654}
1655
1656struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp);
1657
1658static inline struct page *sk_stream_alloc_page(struct sock *sk)
1659{
1660 struct page *page = NULL;
1661
1662 page = alloc_pages(sk->sk_allocation, 0);
1663 if (!page) {
1664 sk->sk_prot->enter_memory_pressure(sk);
1665 sk_stream_moderate_sndbuf(sk);
1666 }
1667 return page;
1668}
1669
1670/*
1671 * Default write policy as shown to user space via poll/select/SIGIO
1672 */
1673static inline int sock_writeable(const struct sock *sk)
1674{
1675 return atomic_read(&sk->sk_wmem_alloc) < (sk->sk_sndbuf >> 1);
1676}
1677
1678static inline gfp_t gfp_any(void)
1679{
1680 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
1681}
1682
1683static inline long sock_rcvtimeo(const struct sock *sk, int noblock)
1684{
1685 return noblock ? 0 : sk->sk_rcvtimeo;
1686}
1687
1688static inline long sock_sndtimeo(const struct sock *sk, int noblock)
1689{
1690 return noblock ? 0 : sk->sk_sndtimeo;
1691}
1692
1693static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
1694{
1695 return (waitall ? len : min_t(int, sk->sk_rcvlowat, len)) ? : 1;
1696}
1697
1698/* Alas, with timeout socket operations are not restartable.
1699 * Compare this to poll().
1700 */
1701static inline int sock_intr_errno(long timeo)
1702{
1703 return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
1704}
1705
1706extern void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
1707 struct sk_buff *skb);
1708
1709static __inline__ void
1710sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
1711{
1712 ktime_t kt = skb->tstamp;
1713 struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
1714
1715 /*
1716 * generate control messages if
1717 * - receive time stamping in software requested (SOCK_RCVTSTAMP
1718 * or SOCK_TIMESTAMPING_RX_SOFTWARE)
1719 * - software time stamp available and wanted
1720 * (SOCK_TIMESTAMPING_SOFTWARE)
1721 * - hardware time stamps available and wanted
1722 * (SOCK_TIMESTAMPING_SYS_HARDWARE or
1723 * SOCK_TIMESTAMPING_RAW_HARDWARE)
1724 */
1725 if (sock_flag(sk, SOCK_RCVTSTAMP) ||
1726 sock_flag(sk, SOCK_TIMESTAMPING_RX_SOFTWARE) ||
1727 (kt.tv64 && sock_flag(sk, SOCK_TIMESTAMPING_SOFTWARE)) ||
1728 (hwtstamps->hwtstamp.tv64 &&
1729 sock_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE)) ||
1730 (hwtstamps->syststamp.tv64 &&
1731 sock_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE)))
1732 __sock_recv_timestamp(msg, sk, skb);
1733 else
1734 sk->sk_stamp = kt;
1735}
1736
1737extern void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
1738 struct sk_buff *skb);
1739
1740static inline void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
1741 struct sk_buff *skb)
1742{
1743#define FLAGS_TS_OR_DROPS ((1UL << SOCK_RXQ_OVFL) | \
1744 (1UL << SOCK_RCVTSTAMP) | \
1745 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE) | \
1746 (1UL << SOCK_TIMESTAMPING_SOFTWARE) | \
1747 (1UL << SOCK_TIMESTAMPING_RAW_HARDWARE) | \
1748 (1UL << SOCK_TIMESTAMPING_SYS_HARDWARE))
1749
1750 if (sk->sk_flags & FLAGS_TS_OR_DROPS)
1751 __sock_recv_ts_and_drops(msg, sk, skb);
1752 else
1753 sk->sk_stamp = skb->tstamp;
1754}
1755
1756/**
1757 * sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
1758 * @sk: socket sending this packet
1759 * @tx_flags: filled with instructions for time stamping
1760 *
1761 * Currently only depends on SOCK_TIMESTAMPING* flags. Returns error code if
1762 * parameters are invalid.
1763 */
1764extern int sock_tx_timestamp(struct sock *sk, __u8 *tx_flags);
1765
1766/**
1767 * sk_eat_skb - Release a skb if it is no longer needed
1768 * @sk: socket to eat this skb from
1769 * @skb: socket buffer to eat
1770 * @copied_early: flag indicating whether DMA operations copied this data early
1771 *
1772 * This routine must be called with interrupts disabled or with the socket
1773 * locked so that the sk_buff queue operation is ok.
1774*/
1775#ifdef CONFIG_NET_DMA
1776static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb, int copied_early)
1777{
1778 __skb_unlink(skb, &sk->sk_receive_queue);
1779 if (!copied_early)
1780 __kfree_skb(skb);
1781 else
1782 __skb_queue_tail(&sk->sk_async_wait_queue, skb);
1783}
1784#else
1785static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb, int copied_early)
1786{
1787 __skb_unlink(skb, &sk->sk_receive_queue);
1788 __kfree_skb(skb);
1789}
1790#endif
1791
1792static inline
1793struct net *sock_net(const struct sock *sk)
1794{
1795 return read_pnet(&sk->sk_net);
1796}
1797
1798static inline
1799void sock_net_set(struct sock *sk, struct net *net)
1800{
1801 write_pnet(&sk->sk_net, net);
1802}
1803
1804/*
1805 * Kernel sockets, f.e. rtnl or icmp_socket, are a part of a namespace.
1806 * They should not hold a reference to a namespace in order to allow
1807 * to stop it.
1808 * Sockets after sk_change_net should be released using sk_release_kernel
1809 */
1810static inline void sk_change_net(struct sock *sk, struct net *net)
1811{
1812 put_net(sock_net(sk));
1813 sock_net_set(sk, hold_net(net));
1814}
1815
1816static inline struct sock *skb_steal_sock(struct sk_buff *skb)
1817{
1818 if (unlikely(skb->sk)) {
1819 struct sock *sk = skb->sk;
1820
1821 skb->destructor = NULL;
1822 skb->sk = NULL;
1823 return sk;
1824 }
1825 return NULL;
1826}
1827
1828extern void sock_enable_timestamp(struct sock *sk, int flag);
1829extern int sock_get_timestamp(struct sock *, struct timeval __user *);
1830extern int sock_get_timestampns(struct sock *, struct timespec __user *);
1831
1832/*
1833 * Enable debug/info messages
1834 */
1835extern int net_msg_warn;
1836#define NETDEBUG(fmt, args...) \
1837 do { if (net_msg_warn) printk(fmt,##args); } while (0)
1838
1839#define LIMIT_NETDEBUG(fmt, args...) \
1840 do { if (net_msg_warn && net_ratelimit()) printk(fmt,##args); } while(0)
1841
1842extern __u32 sysctl_wmem_max;
1843extern __u32 sysctl_rmem_max;
1844
1845extern void sk_init(void);
1846
1847extern int sysctl_optmem_max;
1848
1849extern __u32 sysctl_wmem_default;
1850extern __u32 sysctl_rmem_default;
1851
1852#endif /* _SOCK_H */
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.
5 *
6 * Definitions for the AF_INET socket handler.
7 *
8 * Version: @(#)sock.h 1.0.4 05/13/93
9 *
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>
14 *
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
33 *
34 *
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.
39 */
40#ifndef _SOCK_H
41#define _SOCK_H
42
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/memcontrol.h>
58#include <linux/res_counter.h>
59#include <linux/static_key.h>
60#include <linux/aio.h>
61#include <linux/sched.h>
62
63#include <linux/filter.h>
64#include <linux/rculist_nulls.h>
65#include <linux/poll.h>
66
67#include <linux/atomic.h>
68#include <net/dst.h>
69#include <net/checksum.h>
70
71struct cgroup;
72struct cgroup_subsys;
73#ifdef CONFIG_NET
74int mem_cgroup_sockets_init(struct mem_cgroup *memcg, struct cgroup_subsys *ss);
75void mem_cgroup_sockets_destroy(struct mem_cgroup *memcg);
76#else
77static inline
78int mem_cgroup_sockets_init(struct mem_cgroup *memcg, struct cgroup_subsys *ss)
79{
80 return 0;
81}
82static inline
83void mem_cgroup_sockets_destroy(struct mem_cgroup *memcg)
84{
85}
86#endif
87/*
88 * This structure really needs to be cleaned up.
89 * Most of it is for TCP, and not used by any of
90 * the other protocols.
91 */
92
93/* Define this to get the SOCK_DBG debugging facility. */
94#define SOCK_DEBUGGING
95#ifdef SOCK_DEBUGGING
96#define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \
97 printk(KERN_DEBUG msg); } while (0)
98#else
99/* Validate arguments and do nothing */
100static inline __printf(2, 3)
101void SOCK_DEBUG(const struct sock *sk, const char *msg, ...)
102{
103}
104#endif
105
106/* This is the per-socket lock. The spinlock provides a synchronization
107 * between user contexts and software interrupt processing, whereas the
108 * mini-semaphore synchronizes multiple users amongst themselves.
109 */
110typedef struct {
111 spinlock_t slock;
112 int owned;
113 wait_queue_head_t wq;
114 /*
115 * We express the mutex-alike socket_lock semantics
116 * to the lock validator by explicitly managing
117 * the slock as a lock variant (in addition to
118 * the slock itself):
119 */
120#ifdef CONFIG_DEBUG_LOCK_ALLOC
121 struct lockdep_map dep_map;
122#endif
123} socket_lock_t;
124
125struct sock;
126struct proto;
127struct net;
128
129/**
130 * struct sock_common - minimal network layer representation of sockets
131 * @skc_daddr: Foreign IPv4 addr
132 * @skc_rcv_saddr: Bound local IPv4 addr
133 * @skc_hash: hash value used with various protocol lookup tables
134 * @skc_u16hashes: two u16 hash values used by UDP lookup tables
135 * @skc_family: network address family
136 * @skc_state: Connection state
137 * @skc_reuse: %SO_REUSEADDR setting
138 * @skc_bound_dev_if: bound device index if != 0
139 * @skc_bind_node: bind hash linkage for various protocol lookup tables
140 * @skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol
141 * @skc_prot: protocol handlers inside a network family
142 * @skc_net: reference to the network namespace of this socket
143 * @skc_node: main hash linkage for various protocol lookup tables
144 * @skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol
145 * @skc_tx_queue_mapping: tx queue number for this connection
146 * @skc_refcnt: reference count
147 *
148 * This is the minimal network layer representation of sockets, the header
149 * for struct sock and struct inet_timewait_sock.
150 */
151struct sock_common {
152 /* skc_daddr and skc_rcv_saddr must be grouped :
153 * cf INET_MATCH() and INET_TW_MATCH()
154 */
155 __be32 skc_daddr;
156 __be32 skc_rcv_saddr;
157
158 union {
159 unsigned int skc_hash;
160 __u16 skc_u16hashes[2];
161 };
162 unsigned short skc_family;
163 volatile unsigned char skc_state;
164 unsigned char skc_reuse;
165 int skc_bound_dev_if;
166 union {
167 struct hlist_node skc_bind_node;
168 struct hlist_nulls_node skc_portaddr_node;
169 };
170 struct proto *skc_prot;
171#ifdef CONFIG_NET_NS
172 struct net *skc_net;
173#endif
174 /*
175 * fields between dontcopy_begin/dontcopy_end
176 * are not copied in sock_copy()
177 */
178 /* private: */
179 int skc_dontcopy_begin[0];
180 /* public: */
181 union {
182 struct hlist_node skc_node;
183 struct hlist_nulls_node skc_nulls_node;
184 };
185 int skc_tx_queue_mapping;
186 atomic_t skc_refcnt;
187 /* private: */
188 int skc_dontcopy_end[0];
189 /* public: */
190};
191
192struct cg_proto;
193/**
194 * struct sock - network layer representation of sockets
195 * @__sk_common: shared layout with inet_timewait_sock
196 * @sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
197 * @sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
198 * @sk_lock: synchronizer
199 * @sk_rcvbuf: size of receive buffer in bytes
200 * @sk_wq: sock wait queue and async head
201 * @sk_dst_cache: destination cache
202 * @sk_dst_lock: destination cache lock
203 * @sk_policy: flow policy
204 * @sk_receive_queue: incoming packets
205 * @sk_wmem_alloc: transmit queue bytes committed
206 * @sk_write_queue: Packet sending queue
207 * @sk_async_wait_queue: DMA copied packets
208 * @sk_omem_alloc: "o" is "option" or "other"
209 * @sk_wmem_queued: persistent queue size
210 * @sk_forward_alloc: space allocated forward
211 * @sk_allocation: allocation mode
212 * @sk_sndbuf: size of send buffer in bytes
213 * @sk_flags: %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE,
214 * %SO_OOBINLINE settings, %SO_TIMESTAMPING settings
215 * @sk_no_check: %SO_NO_CHECK setting, wether or not checkup packets
216 * @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
217 * @sk_route_nocaps: forbidden route capabilities (e.g NETIF_F_GSO_MASK)
218 * @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
219 * @sk_gso_max_size: Maximum GSO segment size to build
220 * @sk_gso_max_segs: Maximum number of GSO segments
221 * @sk_lingertime: %SO_LINGER l_linger setting
222 * @sk_backlog: always used with the per-socket spinlock held
223 * @sk_callback_lock: used with the callbacks in the end of this struct
224 * @sk_error_queue: rarely used
225 * @sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt,
226 * IPV6_ADDRFORM for instance)
227 * @sk_err: last error
228 * @sk_err_soft: errors that don't cause failure but are the cause of a
229 * persistent failure not just 'timed out'
230 * @sk_drops: raw/udp drops counter
231 * @sk_ack_backlog: current listen backlog
232 * @sk_max_ack_backlog: listen backlog set in listen()
233 * @sk_priority: %SO_PRIORITY setting
234 * @sk_cgrp_prioidx: socket group's priority map index
235 * @sk_type: socket type (%SOCK_STREAM, etc)
236 * @sk_protocol: which protocol this socket belongs in this network family
237 * @sk_peer_pid: &struct pid for this socket's peer
238 * @sk_peer_cred: %SO_PEERCRED setting
239 * @sk_rcvlowat: %SO_RCVLOWAT setting
240 * @sk_rcvtimeo: %SO_RCVTIMEO setting
241 * @sk_sndtimeo: %SO_SNDTIMEO setting
242 * @sk_rxhash: flow hash received from netif layer
243 * @sk_filter: socket filtering instructions
244 * @sk_protinfo: private area, net family specific, when not using slab
245 * @sk_timer: sock cleanup timer
246 * @sk_stamp: time stamp of last packet received
247 * @sk_socket: Identd and reporting IO signals
248 * @sk_user_data: RPC layer private data
249 * @sk_sndmsg_page: cached page for sendmsg
250 * @sk_sndmsg_off: cached offset for sendmsg
251 * @sk_peek_off: current peek_offset value
252 * @sk_send_head: front of stuff to transmit
253 * @sk_security: used by security modules
254 * @sk_mark: generic packet mark
255 * @sk_classid: this socket's cgroup classid
256 * @sk_cgrp: this socket's cgroup-specific proto data
257 * @sk_write_pending: a write to stream socket waits to start
258 * @sk_state_change: callback to indicate change in the state of the sock
259 * @sk_data_ready: callback to indicate there is data to be processed
260 * @sk_write_space: callback to indicate there is bf sending space available
261 * @sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
262 * @sk_backlog_rcv: callback to process the backlog
263 * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
264 */
265struct sock {
266 /*
267 * Now struct inet_timewait_sock also uses sock_common, so please just
268 * don't add nothing before this first member (__sk_common) --acme
269 */
270 struct sock_common __sk_common;
271#define sk_node __sk_common.skc_node
272#define sk_nulls_node __sk_common.skc_nulls_node
273#define sk_refcnt __sk_common.skc_refcnt
274#define sk_tx_queue_mapping __sk_common.skc_tx_queue_mapping
275
276#define sk_dontcopy_begin __sk_common.skc_dontcopy_begin
277#define sk_dontcopy_end __sk_common.skc_dontcopy_end
278#define sk_hash __sk_common.skc_hash
279#define sk_family __sk_common.skc_family
280#define sk_state __sk_common.skc_state
281#define sk_reuse __sk_common.skc_reuse
282#define sk_bound_dev_if __sk_common.skc_bound_dev_if
283#define sk_bind_node __sk_common.skc_bind_node
284#define sk_prot __sk_common.skc_prot
285#define sk_net __sk_common.skc_net
286 socket_lock_t sk_lock;
287 struct sk_buff_head sk_receive_queue;
288 /*
289 * The backlog queue is special, it is always used with
290 * the per-socket spinlock held and requires low latency
291 * access. Therefore we special case it's implementation.
292 * Note : rmem_alloc is in this structure to fill a hole
293 * on 64bit arches, not because its logically part of
294 * backlog.
295 */
296 struct {
297 atomic_t rmem_alloc;
298 int len;
299 struct sk_buff *head;
300 struct sk_buff *tail;
301 } sk_backlog;
302#define sk_rmem_alloc sk_backlog.rmem_alloc
303 int sk_forward_alloc;
304#ifdef CONFIG_RPS
305 __u32 sk_rxhash;
306#endif
307 atomic_t sk_drops;
308 int sk_rcvbuf;
309
310 struct sk_filter __rcu *sk_filter;
311 struct socket_wq __rcu *sk_wq;
312
313#ifdef CONFIG_NET_DMA
314 struct sk_buff_head sk_async_wait_queue;
315#endif
316
317#ifdef CONFIG_XFRM
318 struct xfrm_policy *sk_policy[2];
319#endif
320 unsigned long sk_flags;
321 struct dst_entry *sk_dst_cache;
322 spinlock_t sk_dst_lock;
323 atomic_t sk_wmem_alloc;
324 atomic_t sk_omem_alloc;
325 int sk_sndbuf;
326 struct sk_buff_head sk_write_queue;
327 kmemcheck_bitfield_begin(flags);
328 unsigned int sk_shutdown : 2,
329 sk_no_check : 2,
330 sk_userlocks : 4,
331 sk_protocol : 8,
332 sk_type : 16;
333 kmemcheck_bitfield_end(flags);
334 int sk_wmem_queued;
335 gfp_t sk_allocation;
336 netdev_features_t sk_route_caps;
337 netdev_features_t sk_route_nocaps;
338 int sk_gso_type;
339 unsigned int sk_gso_max_size;
340 u16 sk_gso_max_segs;
341 int sk_rcvlowat;
342 unsigned long sk_lingertime;
343 struct sk_buff_head sk_error_queue;
344 struct proto *sk_prot_creator;
345 rwlock_t sk_callback_lock;
346 int sk_err,
347 sk_err_soft;
348 unsigned short sk_ack_backlog;
349 unsigned short sk_max_ack_backlog;
350 __u32 sk_priority;
351#ifdef CONFIG_CGROUPS
352 __u32 sk_cgrp_prioidx;
353#endif
354 struct pid *sk_peer_pid;
355 const struct cred *sk_peer_cred;
356 long sk_rcvtimeo;
357 long sk_sndtimeo;
358 void *sk_protinfo;
359 struct timer_list sk_timer;
360 ktime_t sk_stamp;
361 struct socket *sk_socket;
362 void *sk_user_data;
363 struct page *sk_sndmsg_page;
364 struct sk_buff *sk_send_head;
365 __u32 sk_sndmsg_off;
366 __s32 sk_peek_off;
367 int sk_write_pending;
368#ifdef CONFIG_SECURITY
369 void *sk_security;
370#endif
371 __u32 sk_mark;
372 u32 sk_classid;
373 struct cg_proto *sk_cgrp;
374 void (*sk_state_change)(struct sock *sk);
375 void (*sk_data_ready)(struct sock *sk, int bytes);
376 void (*sk_write_space)(struct sock *sk);
377 void (*sk_error_report)(struct sock *sk);
378 int (*sk_backlog_rcv)(struct sock *sk,
379 struct sk_buff *skb);
380 void (*sk_destruct)(struct sock *sk);
381};
382
383/*
384 * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK
385 * or not whether his port will be reused by someone else. SK_FORCE_REUSE
386 * on a socket means that the socket will reuse everybody else's port
387 * without looking at the other's sk_reuse value.
388 */
389
390#define SK_NO_REUSE 0
391#define SK_CAN_REUSE 1
392#define SK_FORCE_REUSE 2
393
394static inline int sk_peek_offset(struct sock *sk, int flags)
395{
396 if ((flags & MSG_PEEK) && (sk->sk_peek_off >= 0))
397 return sk->sk_peek_off;
398 else
399 return 0;
400}
401
402static inline void sk_peek_offset_bwd(struct sock *sk, int val)
403{
404 if (sk->sk_peek_off >= 0) {
405 if (sk->sk_peek_off >= val)
406 sk->sk_peek_off -= val;
407 else
408 sk->sk_peek_off = 0;
409 }
410}
411
412static inline void sk_peek_offset_fwd(struct sock *sk, int val)
413{
414 if (sk->sk_peek_off >= 0)
415 sk->sk_peek_off += val;
416}
417
418/*
419 * Hashed lists helper routines
420 */
421static inline struct sock *sk_entry(const struct hlist_node *node)
422{
423 return hlist_entry(node, struct sock, sk_node);
424}
425
426static inline struct sock *__sk_head(const struct hlist_head *head)
427{
428 return hlist_entry(head->first, struct sock, sk_node);
429}
430
431static inline struct sock *sk_head(const struct hlist_head *head)
432{
433 return hlist_empty(head) ? NULL : __sk_head(head);
434}
435
436static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head)
437{
438 return hlist_nulls_entry(head->first, struct sock, sk_nulls_node);
439}
440
441static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head)
442{
443 return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head);
444}
445
446static inline struct sock *sk_next(const struct sock *sk)
447{
448 return sk->sk_node.next ?
449 hlist_entry(sk->sk_node.next, struct sock, sk_node) : NULL;
450}
451
452static inline struct sock *sk_nulls_next(const struct sock *sk)
453{
454 return (!is_a_nulls(sk->sk_nulls_node.next)) ?
455 hlist_nulls_entry(sk->sk_nulls_node.next,
456 struct sock, sk_nulls_node) :
457 NULL;
458}
459
460static inline bool sk_unhashed(const struct sock *sk)
461{
462 return hlist_unhashed(&sk->sk_node);
463}
464
465static inline bool sk_hashed(const struct sock *sk)
466{
467 return !sk_unhashed(sk);
468}
469
470static inline void sk_node_init(struct hlist_node *node)
471{
472 node->pprev = NULL;
473}
474
475static inline void sk_nulls_node_init(struct hlist_nulls_node *node)
476{
477 node->pprev = NULL;
478}
479
480static inline void __sk_del_node(struct sock *sk)
481{
482 __hlist_del(&sk->sk_node);
483}
484
485/* NB: equivalent to hlist_del_init_rcu */
486static inline bool __sk_del_node_init(struct sock *sk)
487{
488 if (sk_hashed(sk)) {
489 __sk_del_node(sk);
490 sk_node_init(&sk->sk_node);
491 return true;
492 }
493 return false;
494}
495
496/* Grab socket reference count. This operation is valid only
497 when sk is ALREADY grabbed f.e. it is found in hash table
498 or a list and the lookup is made under lock preventing hash table
499 modifications.
500 */
501
502static inline void sock_hold(struct sock *sk)
503{
504 atomic_inc(&sk->sk_refcnt);
505}
506
507/* Ungrab socket in the context, which assumes that socket refcnt
508 cannot hit zero, f.e. it is true in context of any socketcall.
509 */
510static inline void __sock_put(struct sock *sk)
511{
512 atomic_dec(&sk->sk_refcnt);
513}
514
515static inline bool sk_del_node_init(struct sock *sk)
516{
517 bool rc = __sk_del_node_init(sk);
518
519 if (rc) {
520 /* paranoid for a while -acme */
521 WARN_ON(atomic_read(&sk->sk_refcnt) == 1);
522 __sock_put(sk);
523 }
524 return rc;
525}
526#define sk_del_node_init_rcu(sk) sk_del_node_init(sk)
527
528static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk)
529{
530 if (sk_hashed(sk)) {
531 hlist_nulls_del_init_rcu(&sk->sk_nulls_node);
532 return true;
533 }
534 return false;
535}
536
537static inline bool sk_nulls_del_node_init_rcu(struct sock *sk)
538{
539 bool rc = __sk_nulls_del_node_init_rcu(sk);
540
541 if (rc) {
542 /* paranoid for a while -acme */
543 WARN_ON(atomic_read(&sk->sk_refcnt) == 1);
544 __sock_put(sk);
545 }
546 return rc;
547}
548
549static inline void __sk_add_node(struct sock *sk, struct hlist_head *list)
550{
551 hlist_add_head(&sk->sk_node, list);
552}
553
554static inline void sk_add_node(struct sock *sk, struct hlist_head *list)
555{
556 sock_hold(sk);
557 __sk_add_node(sk, list);
558}
559
560static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list)
561{
562 sock_hold(sk);
563 hlist_add_head_rcu(&sk->sk_node, list);
564}
565
566static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
567{
568 hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list);
569}
570
571static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
572{
573 sock_hold(sk);
574 __sk_nulls_add_node_rcu(sk, list);
575}
576
577static inline void __sk_del_bind_node(struct sock *sk)
578{
579 __hlist_del(&sk->sk_bind_node);
580}
581
582static inline void sk_add_bind_node(struct sock *sk,
583 struct hlist_head *list)
584{
585 hlist_add_head(&sk->sk_bind_node, list);
586}
587
588#define sk_for_each(__sk, node, list) \
589 hlist_for_each_entry(__sk, node, list, sk_node)
590#define sk_for_each_rcu(__sk, node, list) \
591 hlist_for_each_entry_rcu(__sk, node, list, sk_node)
592#define sk_nulls_for_each(__sk, node, list) \
593 hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)
594#define sk_nulls_for_each_rcu(__sk, node, list) \
595 hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)
596#define sk_for_each_from(__sk, node) \
597 if (__sk && ({ node = &(__sk)->sk_node; 1; })) \
598 hlist_for_each_entry_from(__sk, node, sk_node)
599#define sk_nulls_for_each_from(__sk, node) \
600 if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \
601 hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node)
602#define sk_for_each_safe(__sk, node, tmp, list) \
603 hlist_for_each_entry_safe(__sk, node, tmp, list, sk_node)
604#define sk_for_each_bound(__sk, node, list) \
605 hlist_for_each_entry(__sk, node, list, sk_bind_node)
606
607/* Sock flags */
608enum sock_flags {
609 SOCK_DEAD,
610 SOCK_DONE,
611 SOCK_URGINLINE,
612 SOCK_KEEPOPEN,
613 SOCK_LINGER,
614 SOCK_DESTROY,
615 SOCK_BROADCAST,
616 SOCK_TIMESTAMP,
617 SOCK_ZAPPED,
618 SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */
619 SOCK_DBG, /* %SO_DEBUG setting */
620 SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
621 SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */
622 SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
623 SOCK_QUEUE_SHRUNK, /* write queue has been shrunk recently */
624 SOCK_TIMESTAMPING_TX_HARDWARE, /* %SOF_TIMESTAMPING_TX_HARDWARE */
625 SOCK_TIMESTAMPING_TX_SOFTWARE, /* %SOF_TIMESTAMPING_TX_SOFTWARE */
626 SOCK_TIMESTAMPING_RX_HARDWARE, /* %SOF_TIMESTAMPING_RX_HARDWARE */
627 SOCK_TIMESTAMPING_RX_SOFTWARE, /* %SOF_TIMESTAMPING_RX_SOFTWARE */
628 SOCK_TIMESTAMPING_SOFTWARE, /* %SOF_TIMESTAMPING_SOFTWARE */
629 SOCK_TIMESTAMPING_RAW_HARDWARE, /* %SOF_TIMESTAMPING_RAW_HARDWARE */
630 SOCK_TIMESTAMPING_SYS_HARDWARE, /* %SOF_TIMESTAMPING_SYS_HARDWARE */
631 SOCK_FASYNC, /* fasync() active */
632 SOCK_RXQ_OVFL,
633 SOCK_ZEROCOPY, /* buffers from userspace */
634 SOCK_WIFI_STATUS, /* push wifi status to userspace */
635 SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS.
636 * Will use last 4 bytes of packet sent from
637 * user-space instead.
638 */
639};
640
641static inline void sock_copy_flags(struct sock *nsk, struct sock *osk)
642{
643 nsk->sk_flags = osk->sk_flags;
644}
645
646static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
647{
648 __set_bit(flag, &sk->sk_flags);
649}
650
651static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag)
652{
653 __clear_bit(flag, &sk->sk_flags);
654}
655
656static inline bool sock_flag(const struct sock *sk, enum sock_flags flag)
657{
658 return test_bit(flag, &sk->sk_flags);
659}
660
661static inline void sk_acceptq_removed(struct sock *sk)
662{
663 sk->sk_ack_backlog--;
664}
665
666static inline void sk_acceptq_added(struct sock *sk)
667{
668 sk->sk_ack_backlog++;
669}
670
671static inline bool sk_acceptq_is_full(const struct sock *sk)
672{
673 return sk->sk_ack_backlog > sk->sk_max_ack_backlog;
674}
675
676/*
677 * Compute minimal free write space needed to queue new packets.
678 */
679static inline int sk_stream_min_wspace(const struct sock *sk)
680{
681 return sk->sk_wmem_queued >> 1;
682}
683
684static inline int sk_stream_wspace(const struct sock *sk)
685{
686 return sk->sk_sndbuf - sk->sk_wmem_queued;
687}
688
689extern void sk_stream_write_space(struct sock *sk);
690
691static inline bool sk_stream_memory_free(const struct sock *sk)
692{
693 return sk->sk_wmem_queued < sk->sk_sndbuf;
694}
695
696/* OOB backlog add */
697static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
698{
699 /* dont let skb dst not refcounted, we are going to leave rcu lock */
700 skb_dst_force(skb);
701
702 if (!sk->sk_backlog.tail)
703 sk->sk_backlog.head = skb;
704 else
705 sk->sk_backlog.tail->next = skb;
706
707 sk->sk_backlog.tail = skb;
708 skb->next = NULL;
709}
710
711/*
712 * Take into account size of receive queue and backlog queue
713 * Do not take into account this skb truesize,
714 * to allow even a single big packet to come.
715 */
716static inline bool sk_rcvqueues_full(const struct sock *sk, const struct sk_buff *skb,
717 unsigned int limit)
718{
719 unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc);
720
721 return qsize > limit;
722}
723
724/* The per-socket spinlock must be held here. */
725static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb,
726 unsigned int limit)
727{
728 if (sk_rcvqueues_full(sk, skb, limit))
729 return -ENOBUFS;
730
731 __sk_add_backlog(sk, skb);
732 sk->sk_backlog.len += skb->truesize;
733 return 0;
734}
735
736static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
737{
738 return sk->sk_backlog_rcv(sk, skb);
739}
740
741static inline void sock_rps_record_flow(const struct sock *sk)
742{
743#ifdef CONFIG_RPS
744 struct rps_sock_flow_table *sock_flow_table;
745
746 rcu_read_lock();
747 sock_flow_table = rcu_dereference(rps_sock_flow_table);
748 rps_record_sock_flow(sock_flow_table, sk->sk_rxhash);
749 rcu_read_unlock();
750#endif
751}
752
753static inline void sock_rps_reset_flow(const struct sock *sk)
754{
755#ifdef CONFIG_RPS
756 struct rps_sock_flow_table *sock_flow_table;
757
758 rcu_read_lock();
759 sock_flow_table = rcu_dereference(rps_sock_flow_table);
760 rps_reset_sock_flow(sock_flow_table, sk->sk_rxhash);
761 rcu_read_unlock();
762#endif
763}
764
765static inline void sock_rps_save_rxhash(struct sock *sk,
766 const struct sk_buff *skb)
767{
768#ifdef CONFIG_RPS
769 if (unlikely(sk->sk_rxhash != skb->rxhash)) {
770 sock_rps_reset_flow(sk);
771 sk->sk_rxhash = skb->rxhash;
772 }
773#endif
774}
775
776static inline void sock_rps_reset_rxhash(struct sock *sk)
777{
778#ifdef CONFIG_RPS
779 sock_rps_reset_flow(sk);
780 sk->sk_rxhash = 0;
781#endif
782}
783
784#define sk_wait_event(__sk, __timeo, __condition) \
785 ({ int __rc; \
786 release_sock(__sk); \
787 __rc = __condition; \
788 if (!__rc) { \
789 *(__timeo) = schedule_timeout(*(__timeo)); \
790 } \
791 lock_sock(__sk); \
792 __rc = __condition; \
793 __rc; \
794 })
795
796extern int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
797extern int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
798extern void sk_stream_wait_close(struct sock *sk, long timeo_p);
799extern int sk_stream_error(struct sock *sk, int flags, int err);
800extern void sk_stream_kill_queues(struct sock *sk);
801
802extern int sk_wait_data(struct sock *sk, long *timeo);
803
804struct request_sock_ops;
805struct timewait_sock_ops;
806struct inet_hashinfo;
807struct raw_hashinfo;
808struct module;
809
810/* Networking protocol blocks we attach to sockets.
811 * socket layer -> transport layer interface
812 * transport -> network interface is defined by struct inet_proto
813 */
814struct proto {
815 void (*close)(struct sock *sk,
816 long timeout);
817 int (*connect)(struct sock *sk,
818 struct sockaddr *uaddr,
819 int addr_len);
820 int (*disconnect)(struct sock *sk, int flags);
821
822 struct sock * (*accept)(struct sock *sk, int flags, int *err);
823
824 int (*ioctl)(struct sock *sk, int cmd,
825 unsigned long arg);
826 int (*init)(struct sock *sk);
827 void (*destroy)(struct sock *sk);
828 void (*shutdown)(struct sock *sk, int how);
829 int (*setsockopt)(struct sock *sk, int level,
830 int optname, char __user *optval,
831 unsigned int optlen);
832 int (*getsockopt)(struct sock *sk, int level,
833 int optname, char __user *optval,
834 int __user *option);
835#ifdef CONFIG_COMPAT
836 int (*compat_setsockopt)(struct sock *sk,
837 int level,
838 int optname, char __user *optval,
839 unsigned int optlen);
840 int (*compat_getsockopt)(struct sock *sk,
841 int level,
842 int optname, char __user *optval,
843 int __user *option);
844 int (*compat_ioctl)(struct sock *sk,
845 unsigned int cmd, unsigned long arg);
846#endif
847 int (*sendmsg)(struct kiocb *iocb, struct sock *sk,
848 struct msghdr *msg, size_t len);
849 int (*recvmsg)(struct kiocb *iocb, struct sock *sk,
850 struct msghdr *msg,
851 size_t len, int noblock, int flags,
852 int *addr_len);
853 int (*sendpage)(struct sock *sk, struct page *page,
854 int offset, size_t size, int flags);
855 int (*bind)(struct sock *sk,
856 struct sockaddr *uaddr, int addr_len);
857
858 int (*backlog_rcv) (struct sock *sk,
859 struct sk_buff *skb);
860
861 /* Keeping track of sk's, looking them up, and port selection methods. */
862 void (*hash)(struct sock *sk);
863 void (*unhash)(struct sock *sk);
864 void (*rehash)(struct sock *sk);
865 int (*get_port)(struct sock *sk, unsigned short snum);
866 void (*clear_sk)(struct sock *sk, int size);
867
868 /* Keeping track of sockets in use */
869#ifdef CONFIG_PROC_FS
870 unsigned int inuse_idx;
871#endif
872
873 /* Memory pressure */
874 void (*enter_memory_pressure)(struct sock *sk);
875 atomic_long_t *memory_allocated; /* Current allocated memory. */
876 struct percpu_counter *sockets_allocated; /* Current number of sockets. */
877 /*
878 * Pressure flag: try to collapse.
879 * Technical note: it is used by multiple contexts non atomically.
880 * All the __sk_mem_schedule() is of this nature: accounting
881 * is strict, actions are advisory and have some latency.
882 */
883 int *memory_pressure;
884 long *sysctl_mem;
885 int *sysctl_wmem;
886 int *sysctl_rmem;
887 int max_header;
888 bool no_autobind;
889
890 struct kmem_cache *slab;
891 unsigned int obj_size;
892 int slab_flags;
893
894 struct percpu_counter *orphan_count;
895
896 struct request_sock_ops *rsk_prot;
897 struct timewait_sock_ops *twsk_prot;
898
899 union {
900 struct inet_hashinfo *hashinfo;
901 struct udp_table *udp_table;
902 struct raw_hashinfo *raw_hash;
903 } h;
904
905 struct module *owner;
906
907 char name[32];
908
909 struct list_head node;
910#ifdef SOCK_REFCNT_DEBUG
911 atomic_t socks;
912#endif
913#ifdef CONFIG_CGROUP_MEM_RES_CTLR_KMEM
914 /*
915 * cgroup specific init/deinit functions. Called once for all
916 * protocols that implement it, from cgroups populate function.
917 * This function has to setup any files the protocol want to
918 * appear in the kmem cgroup filesystem.
919 */
920 int (*init_cgroup)(struct mem_cgroup *memcg,
921 struct cgroup_subsys *ss);
922 void (*destroy_cgroup)(struct mem_cgroup *memcg);
923 struct cg_proto *(*proto_cgroup)(struct mem_cgroup *memcg);
924#endif
925};
926
927/*
928 * Bits in struct cg_proto.flags
929 */
930enum cg_proto_flags {
931 /* Currently active and new sockets should be assigned to cgroups */
932 MEMCG_SOCK_ACTIVE,
933 /* It was ever activated; we must disarm static keys on destruction */
934 MEMCG_SOCK_ACTIVATED,
935};
936
937struct cg_proto {
938 void (*enter_memory_pressure)(struct sock *sk);
939 struct res_counter *memory_allocated; /* Current allocated memory. */
940 struct percpu_counter *sockets_allocated; /* Current number of sockets. */
941 int *memory_pressure;
942 long *sysctl_mem;
943 unsigned long flags;
944 /*
945 * memcg field is used to find which memcg we belong directly
946 * Each memcg struct can hold more than one cg_proto, so container_of
947 * won't really cut.
948 *
949 * The elegant solution would be having an inverse function to
950 * proto_cgroup in struct proto, but that means polluting the structure
951 * for everybody, instead of just for memcg users.
952 */
953 struct mem_cgroup *memcg;
954};
955
956extern int proto_register(struct proto *prot, int alloc_slab);
957extern void proto_unregister(struct proto *prot);
958
959static inline bool memcg_proto_active(struct cg_proto *cg_proto)
960{
961 return test_bit(MEMCG_SOCK_ACTIVE, &cg_proto->flags);
962}
963
964static inline bool memcg_proto_activated(struct cg_proto *cg_proto)
965{
966 return test_bit(MEMCG_SOCK_ACTIVATED, &cg_proto->flags);
967}
968
969#ifdef SOCK_REFCNT_DEBUG
970static inline void sk_refcnt_debug_inc(struct sock *sk)
971{
972 atomic_inc(&sk->sk_prot->socks);
973}
974
975static inline void sk_refcnt_debug_dec(struct sock *sk)
976{
977 atomic_dec(&sk->sk_prot->socks);
978 printk(KERN_DEBUG "%s socket %p released, %d are still alive\n",
979 sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks));
980}
981
982inline void sk_refcnt_debug_release(const struct sock *sk)
983{
984 if (atomic_read(&sk->sk_refcnt) != 1)
985 printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n",
986 sk->sk_prot->name, sk, atomic_read(&sk->sk_refcnt));
987}
988#else /* SOCK_REFCNT_DEBUG */
989#define sk_refcnt_debug_inc(sk) do { } while (0)
990#define sk_refcnt_debug_dec(sk) do { } while (0)
991#define sk_refcnt_debug_release(sk) do { } while (0)
992#endif /* SOCK_REFCNT_DEBUG */
993
994#if defined(CONFIG_CGROUP_MEM_RES_CTLR_KMEM) && defined(CONFIG_NET)
995extern struct static_key memcg_socket_limit_enabled;
996static inline struct cg_proto *parent_cg_proto(struct proto *proto,
997 struct cg_proto *cg_proto)
998{
999 return proto->proto_cgroup(parent_mem_cgroup(cg_proto->memcg));
1000}
1001#define mem_cgroup_sockets_enabled static_key_false(&memcg_socket_limit_enabled)
1002#else
1003#define mem_cgroup_sockets_enabled 0
1004static inline struct cg_proto *parent_cg_proto(struct proto *proto,
1005 struct cg_proto *cg_proto)
1006{
1007 return NULL;
1008}
1009#endif
1010
1011
1012static inline bool sk_has_memory_pressure(const struct sock *sk)
1013{
1014 return sk->sk_prot->memory_pressure != NULL;
1015}
1016
1017static inline bool sk_under_memory_pressure(const struct sock *sk)
1018{
1019 if (!sk->sk_prot->memory_pressure)
1020 return false;
1021
1022 if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1023 return !!*sk->sk_cgrp->memory_pressure;
1024
1025 return !!*sk->sk_prot->memory_pressure;
1026}
1027
1028static inline void sk_leave_memory_pressure(struct sock *sk)
1029{
1030 int *memory_pressure = sk->sk_prot->memory_pressure;
1031
1032 if (!memory_pressure)
1033 return;
1034
1035 if (*memory_pressure)
1036 *memory_pressure = 0;
1037
1038 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1039 struct cg_proto *cg_proto = sk->sk_cgrp;
1040 struct proto *prot = sk->sk_prot;
1041
1042 for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto))
1043 if (*cg_proto->memory_pressure)
1044 *cg_proto->memory_pressure = 0;
1045 }
1046
1047}
1048
1049static inline void sk_enter_memory_pressure(struct sock *sk)
1050{
1051 if (!sk->sk_prot->enter_memory_pressure)
1052 return;
1053
1054 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1055 struct cg_proto *cg_proto = sk->sk_cgrp;
1056 struct proto *prot = sk->sk_prot;
1057
1058 for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto))
1059 cg_proto->enter_memory_pressure(sk);
1060 }
1061
1062 sk->sk_prot->enter_memory_pressure(sk);
1063}
1064
1065static inline long sk_prot_mem_limits(const struct sock *sk, int index)
1066{
1067 long *prot = sk->sk_prot->sysctl_mem;
1068 if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1069 prot = sk->sk_cgrp->sysctl_mem;
1070 return prot[index];
1071}
1072
1073static inline void memcg_memory_allocated_add(struct cg_proto *prot,
1074 unsigned long amt,
1075 int *parent_status)
1076{
1077 struct res_counter *fail;
1078 int ret;
1079
1080 ret = res_counter_charge_nofail(prot->memory_allocated,
1081 amt << PAGE_SHIFT, &fail);
1082 if (ret < 0)
1083 *parent_status = OVER_LIMIT;
1084}
1085
1086static inline void memcg_memory_allocated_sub(struct cg_proto *prot,
1087 unsigned long amt)
1088{
1089 res_counter_uncharge(prot->memory_allocated, amt << PAGE_SHIFT);
1090}
1091
1092static inline u64 memcg_memory_allocated_read(struct cg_proto *prot)
1093{
1094 u64 ret;
1095 ret = res_counter_read_u64(prot->memory_allocated, RES_USAGE);
1096 return ret >> PAGE_SHIFT;
1097}
1098
1099static inline long
1100sk_memory_allocated(const struct sock *sk)
1101{
1102 struct proto *prot = sk->sk_prot;
1103 if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1104 return memcg_memory_allocated_read(sk->sk_cgrp);
1105
1106 return atomic_long_read(prot->memory_allocated);
1107}
1108
1109static inline long
1110sk_memory_allocated_add(struct sock *sk, int amt, int *parent_status)
1111{
1112 struct proto *prot = sk->sk_prot;
1113
1114 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1115 memcg_memory_allocated_add(sk->sk_cgrp, amt, parent_status);
1116 /* update the root cgroup regardless */
1117 atomic_long_add_return(amt, prot->memory_allocated);
1118 return memcg_memory_allocated_read(sk->sk_cgrp);
1119 }
1120
1121 return atomic_long_add_return(amt, prot->memory_allocated);
1122}
1123
1124static inline void
1125sk_memory_allocated_sub(struct sock *sk, int amt)
1126{
1127 struct proto *prot = sk->sk_prot;
1128
1129 if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1130 memcg_memory_allocated_sub(sk->sk_cgrp, amt);
1131
1132 atomic_long_sub(amt, prot->memory_allocated);
1133}
1134
1135static inline void sk_sockets_allocated_dec(struct sock *sk)
1136{
1137 struct proto *prot = sk->sk_prot;
1138
1139 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1140 struct cg_proto *cg_proto = sk->sk_cgrp;
1141
1142 for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto))
1143 percpu_counter_dec(cg_proto->sockets_allocated);
1144 }
1145
1146 percpu_counter_dec(prot->sockets_allocated);
1147}
1148
1149static inline void sk_sockets_allocated_inc(struct sock *sk)
1150{
1151 struct proto *prot = sk->sk_prot;
1152
1153 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1154 struct cg_proto *cg_proto = sk->sk_cgrp;
1155
1156 for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto))
1157 percpu_counter_inc(cg_proto->sockets_allocated);
1158 }
1159
1160 percpu_counter_inc(prot->sockets_allocated);
1161}
1162
1163static inline int
1164sk_sockets_allocated_read_positive(struct sock *sk)
1165{
1166 struct proto *prot = sk->sk_prot;
1167
1168 if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1169 return percpu_counter_read_positive(sk->sk_cgrp->sockets_allocated);
1170
1171 return percpu_counter_read_positive(prot->sockets_allocated);
1172}
1173
1174static inline int
1175proto_sockets_allocated_sum_positive(struct proto *prot)
1176{
1177 return percpu_counter_sum_positive(prot->sockets_allocated);
1178}
1179
1180static inline long
1181proto_memory_allocated(struct proto *prot)
1182{
1183 return atomic_long_read(prot->memory_allocated);
1184}
1185
1186static inline bool
1187proto_memory_pressure(struct proto *prot)
1188{
1189 if (!prot->memory_pressure)
1190 return false;
1191 return !!*prot->memory_pressure;
1192}
1193
1194
1195#ifdef CONFIG_PROC_FS
1196/* Called with local bh disabled */
1197extern void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc);
1198extern int sock_prot_inuse_get(struct net *net, struct proto *proto);
1199#else
1200static inline void sock_prot_inuse_add(struct net *net, struct proto *prot,
1201 int inc)
1202{
1203}
1204#endif
1205
1206
1207/* With per-bucket locks this operation is not-atomic, so that
1208 * this version is not worse.
1209 */
1210static inline void __sk_prot_rehash(struct sock *sk)
1211{
1212 sk->sk_prot->unhash(sk);
1213 sk->sk_prot->hash(sk);
1214}
1215
1216void sk_prot_clear_portaddr_nulls(struct sock *sk, int size);
1217
1218/* About 10 seconds */
1219#define SOCK_DESTROY_TIME (10*HZ)
1220
1221/* Sockets 0-1023 can't be bound to unless you are superuser */
1222#define PROT_SOCK 1024
1223
1224#define SHUTDOWN_MASK 3
1225#define RCV_SHUTDOWN 1
1226#define SEND_SHUTDOWN 2
1227
1228#define SOCK_SNDBUF_LOCK 1
1229#define SOCK_RCVBUF_LOCK 2
1230#define SOCK_BINDADDR_LOCK 4
1231#define SOCK_BINDPORT_LOCK 8
1232
1233/* sock_iocb: used to kick off async processing of socket ios */
1234struct sock_iocb {
1235 struct list_head list;
1236
1237 int flags;
1238 int size;
1239 struct socket *sock;
1240 struct sock *sk;
1241 struct scm_cookie *scm;
1242 struct msghdr *msg, async_msg;
1243 struct kiocb *kiocb;
1244};
1245
1246static inline struct sock_iocb *kiocb_to_siocb(struct kiocb *iocb)
1247{
1248 return (struct sock_iocb *)iocb->private;
1249}
1250
1251static inline struct kiocb *siocb_to_kiocb(struct sock_iocb *si)
1252{
1253 return si->kiocb;
1254}
1255
1256struct socket_alloc {
1257 struct socket socket;
1258 struct inode vfs_inode;
1259};
1260
1261static inline struct socket *SOCKET_I(struct inode *inode)
1262{
1263 return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
1264}
1265
1266static inline struct inode *SOCK_INODE(struct socket *socket)
1267{
1268 return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
1269}
1270
1271/*
1272 * Functions for memory accounting
1273 */
1274extern int __sk_mem_schedule(struct sock *sk, int size, int kind);
1275extern void __sk_mem_reclaim(struct sock *sk);
1276
1277#define SK_MEM_QUANTUM ((int)PAGE_SIZE)
1278#define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM)
1279#define SK_MEM_SEND 0
1280#define SK_MEM_RECV 1
1281
1282static inline int sk_mem_pages(int amt)
1283{
1284 return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT;
1285}
1286
1287static inline bool sk_has_account(struct sock *sk)
1288{
1289 /* return true if protocol supports memory accounting */
1290 return !!sk->sk_prot->memory_allocated;
1291}
1292
1293static inline bool sk_wmem_schedule(struct sock *sk, int size)
1294{
1295 if (!sk_has_account(sk))
1296 return true;
1297 return size <= sk->sk_forward_alloc ||
1298 __sk_mem_schedule(sk, size, SK_MEM_SEND);
1299}
1300
1301static inline bool sk_rmem_schedule(struct sock *sk, int size)
1302{
1303 if (!sk_has_account(sk))
1304 return true;
1305 return size <= sk->sk_forward_alloc ||
1306 __sk_mem_schedule(sk, size, SK_MEM_RECV);
1307}
1308
1309static inline void sk_mem_reclaim(struct sock *sk)
1310{
1311 if (!sk_has_account(sk))
1312 return;
1313 if (sk->sk_forward_alloc >= SK_MEM_QUANTUM)
1314 __sk_mem_reclaim(sk);
1315}
1316
1317static inline void sk_mem_reclaim_partial(struct sock *sk)
1318{
1319 if (!sk_has_account(sk))
1320 return;
1321 if (sk->sk_forward_alloc > SK_MEM_QUANTUM)
1322 __sk_mem_reclaim(sk);
1323}
1324
1325static inline void sk_mem_charge(struct sock *sk, int size)
1326{
1327 if (!sk_has_account(sk))
1328 return;
1329 sk->sk_forward_alloc -= size;
1330}
1331
1332static inline void sk_mem_uncharge(struct sock *sk, int size)
1333{
1334 if (!sk_has_account(sk))
1335 return;
1336 sk->sk_forward_alloc += size;
1337}
1338
1339static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb)
1340{
1341 sock_set_flag(sk, SOCK_QUEUE_SHRUNK);
1342 sk->sk_wmem_queued -= skb->truesize;
1343 sk_mem_uncharge(sk, skb->truesize);
1344 __kfree_skb(skb);
1345}
1346
1347/* Used by processes to "lock" a socket state, so that
1348 * interrupts and bottom half handlers won't change it
1349 * from under us. It essentially blocks any incoming
1350 * packets, so that we won't get any new data or any
1351 * packets that change the state of the socket.
1352 *
1353 * While locked, BH processing will add new packets to
1354 * the backlog queue. This queue is processed by the
1355 * owner of the socket lock right before it is released.
1356 *
1357 * Since ~2.3.5 it is also exclusive sleep lock serializing
1358 * accesses from user process context.
1359 */
1360#define sock_owned_by_user(sk) ((sk)->sk_lock.owned)
1361
1362/*
1363 * Macro so as to not evaluate some arguments when
1364 * lockdep is not enabled.
1365 *
1366 * Mark both the sk_lock and the sk_lock.slock as a
1367 * per-address-family lock class.
1368 */
1369#define sock_lock_init_class_and_name(sk, sname, skey, name, key) \
1370do { \
1371 sk->sk_lock.owned = 0; \
1372 init_waitqueue_head(&sk->sk_lock.wq); \
1373 spin_lock_init(&(sk)->sk_lock.slock); \
1374 debug_check_no_locks_freed((void *)&(sk)->sk_lock, \
1375 sizeof((sk)->sk_lock)); \
1376 lockdep_set_class_and_name(&(sk)->sk_lock.slock, \
1377 (skey), (sname)); \
1378 lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \
1379} while (0)
1380
1381extern void lock_sock_nested(struct sock *sk, int subclass);
1382
1383static inline void lock_sock(struct sock *sk)
1384{
1385 lock_sock_nested(sk, 0);
1386}
1387
1388extern void release_sock(struct sock *sk);
1389
1390/* BH context may only use the following locking interface. */
1391#define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock))
1392#define bh_lock_sock_nested(__sk) \
1393 spin_lock_nested(&((__sk)->sk_lock.slock), \
1394 SINGLE_DEPTH_NESTING)
1395#define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock))
1396
1397extern bool lock_sock_fast(struct sock *sk);
1398/**
1399 * unlock_sock_fast - complement of lock_sock_fast
1400 * @sk: socket
1401 * @slow: slow mode
1402 *
1403 * fast unlock socket for user context.
1404 * If slow mode is on, we call regular release_sock()
1405 */
1406static inline void unlock_sock_fast(struct sock *sk, bool slow)
1407{
1408 if (slow)
1409 release_sock(sk);
1410 else
1411 spin_unlock_bh(&sk->sk_lock.slock);
1412}
1413
1414
1415extern struct sock *sk_alloc(struct net *net, int family,
1416 gfp_t priority,
1417 struct proto *prot);
1418extern void sk_free(struct sock *sk);
1419extern void sk_release_kernel(struct sock *sk);
1420extern struct sock *sk_clone_lock(const struct sock *sk,
1421 const gfp_t priority);
1422
1423extern struct sk_buff *sock_wmalloc(struct sock *sk,
1424 unsigned long size, int force,
1425 gfp_t priority);
1426extern struct sk_buff *sock_rmalloc(struct sock *sk,
1427 unsigned long size, int force,
1428 gfp_t priority);
1429extern void sock_wfree(struct sk_buff *skb);
1430extern void sock_rfree(struct sk_buff *skb);
1431
1432extern int sock_setsockopt(struct socket *sock, int level,
1433 int op, char __user *optval,
1434 unsigned int optlen);
1435
1436extern int sock_getsockopt(struct socket *sock, int level,
1437 int op, char __user *optval,
1438 int __user *optlen);
1439extern struct sk_buff *sock_alloc_send_skb(struct sock *sk,
1440 unsigned long size,
1441 int noblock,
1442 int *errcode);
1443extern struct sk_buff *sock_alloc_send_pskb(struct sock *sk,
1444 unsigned long header_len,
1445 unsigned long data_len,
1446 int noblock,
1447 int *errcode);
1448extern void *sock_kmalloc(struct sock *sk, int size,
1449 gfp_t priority);
1450extern void sock_kfree_s(struct sock *sk, void *mem, int size);
1451extern void sk_send_sigurg(struct sock *sk);
1452
1453#ifdef CONFIG_CGROUPS
1454extern void sock_update_classid(struct sock *sk);
1455#else
1456static inline void sock_update_classid(struct sock *sk)
1457{
1458}
1459#endif
1460
1461/*
1462 * Functions to fill in entries in struct proto_ops when a protocol
1463 * does not implement a particular function.
1464 */
1465extern int sock_no_bind(struct socket *,
1466 struct sockaddr *, int);
1467extern int sock_no_connect(struct socket *,
1468 struct sockaddr *, int, int);
1469extern int sock_no_socketpair(struct socket *,
1470 struct socket *);
1471extern int sock_no_accept(struct socket *,
1472 struct socket *, int);
1473extern int sock_no_getname(struct socket *,
1474 struct sockaddr *, int *, int);
1475extern unsigned int sock_no_poll(struct file *, struct socket *,
1476 struct poll_table_struct *);
1477extern int sock_no_ioctl(struct socket *, unsigned int,
1478 unsigned long);
1479extern int sock_no_listen(struct socket *, int);
1480extern int sock_no_shutdown(struct socket *, int);
1481extern int sock_no_getsockopt(struct socket *, int , int,
1482 char __user *, int __user *);
1483extern int sock_no_setsockopt(struct socket *, int, int,
1484 char __user *, unsigned int);
1485extern int sock_no_sendmsg(struct kiocb *, struct socket *,
1486 struct msghdr *, size_t);
1487extern int sock_no_recvmsg(struct kiocb *, struct socket *,
1488 struct msghdr *, size_t, int);
1489extern int sock_no_mmap(struct file *file,
1490 struct socket *sock,
1491 struct vm_area_struct *vma);
1492extern ssize_t sock_no_sendpage(struct socket *sock,
1493 struct page *page,
1494 int offset, size_t size,
1495 int flags);
1496
1497/*
1498 * Functions to fill in entries in struct proto_ops when a protocol
1499 * uses the inet style.
1500 */
1501extern int sock_common_getsockopt(struct socket *sock, int level, int optname,
1502 char __user *optval, int __user *optlen);
1503extern int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock,
1504 struct msghdr *msg, size_t size, int flags);
1505extern int sock_common_setsockopt(struct socket *sock, int level, int optname,
1506 char __user *optval, unsigned int optlen);
1507extern int compat_sock_common_getsockopt(struct socket *sock, int level,
1508 int optname, char __user *optval, int __user *optlen);
1509extern int compat_sock_common_setsockopt(struct socket *sock, int level,
1510 int optname, char __user *optval, unsigned int optlen);
1511
1512extern void sk_common_release(struct sock *sk);
1513
1514/*
1515 * Default socket callbacks and setup code
1516 */
1517
1518/* Initialise core socket variables */
1519extern void sock_init_data(struct socket *sock, struct sock *sk);
1520
1521extern void sk_filter_release_rcu(struct rcu_head *rcu);
1522
1523/**
1524 * sk_filter_release - release a socket filter
1525 * @fp: filter to remove
1526 *
1527 * Remove a filter from a socket and release its resources.
1528 */
1529
1530static inline void sk_filter_release(struct sk_filter *fp)
1531{
1532 if (atomic_dec_and_test(&fp->refcnt))
1533 call_rcu(&fp->rcu, sk_filter_release_rcu);
1534}
1535
1536static inline void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp)
1537{
1538 unsigned int size = sk_filter_len(fp);
1539
1540 atomic_sub(size, &sk->sk_omem_alloc);
1541 sk_filter_release(fp);
1542}
1543
1544static inline void sk_filter_charge(struct sock *sk, struct sk_filter *fp)
1545{
1546 atomic_inc(&fp->refcnt);
1547 atomic_add(sk_filter_len(fp), &sk->sk_omem_alloc);
1548}
1549
1550/*
1551 * Socket reference counting postulates.
1552 *
1553 * * Each user of socket SHOULD hold a reference count.
1554 * * Each access point to socket (an hash table bucket, reference from a list,
1555 * running timer, skb in flight MUST hold a reference count.
1556 * * When reference count hits 0, it means it will never increase back.
1557 * * When reference count hits 0, it means that no references from
1558 * outside exist to this socket and current process on current CPU
1559 * is last user and may/should destroy this socket.
1560 * * sk_free is called from any context: process, BH, IRQ. When
1561 * it is called, socket has no references from outside -> sk_free
1562 * may release descendant resources allocated by the socket, but
1563 * to the time when it is called, socket is NOT referenced by any
1564 * hash tables, lists etc.
1565 * * Packets, delivered from outside (from network or from another process)
1566 * and enqueued on receive/error queues SHOULD NOT grab reference count,
1567 * when they sit in queue. Otherwise, packets will leak to hole, when
1568 * socket is looked up by one cpu and unhasing is made by another CPU.
1569 * It is true for udp/raw, netlink (leak to receive and error queues), tcp
1570 * (leak to backlog). Packet socket does all the processing inside
1571 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
1572 * use separate SMP lock, so that they are prone too.
1573 */
1574
1575/* Ungrab socket and destroy it, if it was the last reference. */
1576static inline void sock_put(struct sock *sk)
1577{
1578 if (atomic_dec_and_test(&sk->sk_refcnt))
1579 sk_free(sk);
1580}
1581
1582extern int sk_receive_skb(struct sock *sk, struct sk_buff *skb,
1583 const int nested);
1584
1585static inline void sk_tx_queue_set(struct sock *sk, int tx_queue)
1586{
1587 sk->sk_tx_queue_mapping = tx_queue;
1588}
1589
1590static inline void sk_tx_queue_clear(struct sock *sk)
1591{
1592 sk->sk_tx_queue_mapping = -1;
1593}
1594
1595static inline int sk_tx_queue_get(const struct sock *sk)
1596{
1597 return sk ? sk->sk_tx_queue_mapping : -1;
1598}
1599
1600static inline void sk_set_socket(struct sock *sk, struct socket *sock)
1601{
1602 sk_tx_queue_clear(sk);
1603 sk->sk_socket = sock;
1604}
1605
1606static inline wait_queue_head_t *sk_sleep(struct sock *sk)
1607{
1608 BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0);
1609 return &rcu_dereference_raw(sk->sk_wq)->wait;
1610}
1611/* Detach socket from process context.
1612 * Announce socket dead, detach it from wait queue and inode.
1613 * Note that parent inode held reference count on this struct sock,
1614 * we do not release it in this function, because protocol
1615 * probably wants some additional cleanups or even continuing
1616 * to work with this socket (TCP).
1617 */
1618static inline void sock_orphan(struct sock *sk)
1619{
1620 write_lock_bh(&sk->sk_callback_lock);
1621 sock_set_flag(sk, SOCK_DEAD);
1622 sk_set_socket(sk, NULL);
1623 sk->sk_wq = NULL;
1624 write_unlock_bh(&sk->sk_callback_lock);
1625}
1626
1627static inline void sock_graft(struct sock *sk, struct socket *parent)
1628{
1629 write_lock_bh(&sk->sk_callback_lock);
1630 sk->sk_wq = parent->wq;
1631 parent->sk = sk;
1632 sk_set_socket(sk, parent);
1633 security_sock_graft(sk, parent);
1634 write_unlock_bh(&sk->sk_callback_lock);
1635}
1636
1637extern int sock_i_uid(struct sock *sk);
1638extern unsigned long sock_i_ino(struct sock *sk);
1639
1640static inline struct dst_entry *
1641__sk_dst_get(struct sock *sk)
1642{
1643 return rcu_dereference_check(sk->sk_dst_cache, sock_owned_by_user(sk) ||
1644 lockdep_is_held(&sk->sk_lock.slock));
1645}
1646
1647static inline struct dst_entry *
1648sk_dst_get(struct sock *sk)
1649{
1650 struct dst_entry *dst;
1651
1652 rcu_read_lock();
1653 dst = rcu_dereference(sk->sk_dst_cache);
1654 if (dst)
1655 dst_hold(dst);
1656 rcu_read_unlock();
1657 return dst;
1658}
1659
1660extern void sk_reset_txq(struct sock *sk);
1661
1662static inline void dst_negative_advice(struct sock *sk)
1663{
1664 struct dst_entry *ndst, *dst = __sk_dst_get(sk);
1665
1666 if (dst && dst->ops->negative_advice) {
1667 ndst = dst->ops->negative_advice(dst);
1668
1669 if (ndst != dst) {
1670 rcu_assign_pointer(sk->sk_dst_cache, ndst);
1671 sk_reset_txq(sk);
1672 }
1673 }
1674}
1675
1676static inline void
1677__sk_dst_set(struct sock *sk, struct dst_entry *dst)
1678{
1679 struct dst_entry *old_dst;
1680
1681 sk_tx_queue_clear(sk);
1682 /*
1683 * This can be called while sk is owned by the caller only,
1684 * with no state that can be checked in a rcu_dereference_check() cond
1685 */
1686 old_dst = rcu_dereference_raw(sk->sk_dst_cache);
1687 rcu_assign_pointer(sk->sk_dst_cache, dst);
1688 dst_release(old_dst);
1689}
1690
1691static inline void
1692sk_dst_set(struct sock *sk, struct dst_entry *dst)
1693{
1694 spin_lock(&sk->sk_dst_lock);
1695 __sk_dst_set(sk, dst);
1696 spin_unlock(&sk->sk_dst_lock);
1697}
1698
1699static inline void
1700__sk_dst_reset(struct sock *sk)
1701{
1702 __sk_dst_set(sk, NULL);
1703}
1704
1705static inline void
1706sk_dst_reset(struct sock *sk)
1707{
1708 spin_lock(&sk->sk_dst_lock);
1709 __sk_dst_reset(sk);
1710 spin_unlock(&sk->sk_dst_lock);
1711}
1712
1713extern struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
1714
1715extern struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
1716
1717static inline bool sk_can_gso(const struct sock *sk)
1718{
1719 return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type);
1720}
1721
1722extern void sk_setup_caps(struct sock *sk, struct dst_entry *dst);
1723
1724static inline void sk_nocaps_add(struct sock *sk, netdev_features_t flags)
1725{
1726 sk->sk_route_nocaps |= flags;
1727 sk->sk_route_caps &= ~flags;
1728}
1729
1730static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
1731 char __user *from, char *to,
1732 int copy, int offset)
1733{
1734 if (skb->ip_summed == CHECKSUM_NONE) {
1735 int err = 0;
1736 __wsum csum = csum_and_copy_from_user(from, to, copy, 0, &err);
1737 if (err)
1738 return err;
1739 skb->csum = csum_block_add(skb->csum, csum, offset);
1740 } else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
1741 if (!access_ok(VERIFY_READ, from, copy) ||
1742 __copy_from_user_nocache(to, from, copy))
1743 return -EFAULT;
1744 } else if (copy_from_user(to, from, copy))
1745 return -EFAULT;
1746
1747 return 0;
1748}
1749
1750static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
1751 char __user *from, int copy)
1752{
1753 int err, offset = skb->len;
1754
1755 err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy),
1756 copy, offset);
1757 if (err)
1758 __skb_trim(skb, offset);
1759
1760 return err;
1761}
1762
1763static inline int skb_copy_to_page_nocache(struct sock *sk, char __user *from,
1764 struct sk_buff *skb,
1765 struct page *page,
1766 int off, int copy)
1767{
1768 int err;
1769
1770 err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off,
1771 copy, skb->len);
1772 if (err)
1773 return err;
1774
1775 skb->len += copy;
1776 skb->data_len += copy;
1777 skb->truesize += copy;
1778 sk->sk_wmem_queued += copy;
1779 sk_mem_charge(sk, copy);
1780 return 0;
1781}
1782
1783static inline int skb_copy_to_page(struct sock *sk, char __user *from,
1784 struct sk_buff *skb, struct page *page,
1785 int off, int copy)
1786{
1787 if (skb->ip_summed == CHECKSUM_NONE) {
1788 int err = 0;
1789 __wsum csum = csum_and_copy_from_user(from,
1790 page_address(page) + off,
1791 copy, 0, &err);
1792 if (err)
1793 return err;
1794 skb->csum = csum_block_add(skb->csum, csum, skb->len);
1795 } else if (copy_from_user(page_address(page) + off, from, copy))
1796 return -EFAULT;
1797
1798 skb->len += copy;
1799 skb->data_len += copy;
1800 skb->truesize += copy;
1801 sk->sk_wmem_queued += copy;
1802 sk_mem_charge(sk, copy);
1803 return 0;
1804}
1805
1806/**
1807 * sk_wmem_alloc_get - returns write allocations
1808 * @sk: socket
1809 *
1810 * Returns sk_wmem_alloc minus initial offset of one
1811 */
1812static inline int sk_wmem_alloc_get(const struct sock *sk)
1813{
1814 return atomic_read(&sk->sk_wmem_alloc) - 1;
1815}
1816
1817/**
1818 * sk_rmem_alloc_get - returns read allocations
1819 * @sk: socket
1820 *
1821 * Returns sk_rmem_alloc
1822 */
1823static inline int sk_rmem_alloc_get(const struct sock *sk)
1824{
1825 return atomic_read(&sk->sk_rmem_alloc);
1826}
1827
1828/**
1829 * sk_has_allocations - check if allocations are outstanding
1830 * @sk: socket
1831 *
1832 * Returns true if socket has write or read allocations
1833 */
1834static inline bool sk_has_allocations(const struct sock *sk)
1835{
1836 return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk);
1837}
1838
1839/**
1840 * wq_has_sleeper - check if there are any waiting processes
1841 * @wq: struct socket_wq
1842 *
1843 * Returns true if socket_wq has waiting processes
1844 *
1845 * The purpose of the wq_has_sleeper and sock_poll_wait is to wrap the memory
1846 * barrier call. They were added due to the race found within the tcp code.
1847 *
1848 * Consider following tcp code paths:
1849 *
1850 * CPU1 CPU2
1851 *
1852 * sys_select receive packet
1853 * ... ...
1854 * __add_wait_queue update tp->rcv_nxt
1855 * ... ...
1856 * tp->rcv_nxt check sock_def_readable
1857 * ... {
1858 * schedule rcu_read_lock();
1859 * wq = rcu_dereference(sk->sk_wq);
1860 * if (wq && waitqueue_active(&wq->wait))
1861 * wake_up_interruptible(&wq->wait)
1862 * ...
1863 * }
1864 *
1865 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
1866 * in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1
1867 * could then endup calling schedule and sleep forever if there are no more
1868 * data on the socket.
1869 *
1870 */
1871static inline bool wq_has_sleeper(struct socket_wq *wq)
1872{
1873 /* We need to be sure we are in sync with the
1874 * add_wait_queue modifications to the wait queue.
1875 *
1876 * This memory barrier is paired in the sock_poll_wait.
1877 */
1878 smp_mb();
1879 return wq && waitqueue_active(&wq->wait);
1880}
1881
1882/**
1883 * sock_poll_wait - place memory barrier behind the poll_wait call.
1884 * @filp: file
1885 * @wait_address: socket wait queue
1886 * @p: poll_table
1887 *
1888 * See the comments in the wq_has_sleeper function.
1889 */
1890static inline void sock_poll_wait(struct file *filp,
1891 wait_queue_head_t *wait_address, poll_table *p)
1892{
1893 if (!poll_does_not_wait(p) && wait_address) {
1894 poll_wait(filp, wait_address, p);
1895 /* We need to be sure we are in sync with the
1896 * socket flags modification.
1897 *
1898 * This memory barrier is paired in the wq_has_sleeper.
1899 */
1900 smp_mb();
1901 }
1902}
1903
1904/*
1905 * Queue a received datagram if it will fit. Stream and sequenced
1906 * protocols can't normally use this as they need to fit buffers in
1907 * and play with them.
1908 *
1909 * Inlined as it's very short and called for pretty much every
1910 * packet ever received.
1911 */
1912
1913static inline void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
1914{
1915 skb_orphan(skb);
1916 skb->sk = sk;
1917 skb->destructor = sock_wfree;
1918 /*
1919 * We used to take a refcount on sk, but following operation
1920 * is enough to guarantee sk_free() wont free this sock until
1921 * all in-flight packets are completed
1922 */
1923 atomic_add(skb->truesize, &sk->sk_wmem_alloc);
1924}
1925
1926static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
1927{
1928 skb_orphan(skb);
1929 skb->sk = sk;
1930 skb->destructor = sock_rfree;
1931 atomic_add(skb->truesize, &sk->sk_rmem_alloc);
1932 sk_mem_charge(sk, skb->truesize);
1933}
1934
1935extern void sk_reset_timer(struct sock *sk, struct timer_list *timer,
1936 unsigned long expires);
1937
1938extern void sk_stop_timer(struct sock *sk, struct timer_list *timer);
1939
1940extern int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
1941
1942extern int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
1943
1944/*
1945 * Recover an error report and clear atomically
1946 */
1947
1948static inline int sock_error(struct sock *sk)
1949{
1950 int err;
1951 if (likely(!sk->sk_err))
1952 return 0;
1953 err = xchg(&sk->sk_err, 0);
1954 return -err;
1955}
1956
1957static inline unsigned long sock_wspace(struct sock *sk)
1958{
1959 int amt = 0;
1960
1961 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
1962 amt = sk->sk_sndbuf - atomic_read(&sk->sk_wmem_alloc);
1963 if (amt < 0)
1964 amt = 0;
1965 }
1966 return amt;
1967}
1968
1969static inline void sk_wake_async(struct sock *sk, int how, int band)
1970{
1971 if (sock_flag(sk, SOCK_FASYNC))
1972 sock_wake_async(sk->sk_socket, how, band);
1973}
1974
1975#define SOCK_MIN_SNDBUF 2048
1976/*
1977 * Since sk_rmem_alloc sums skb->truesize, even a small frame might need
1978 * sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak
1979 */
1980#define SOCK_MIN_RCVBUF (2048 + sizeof(struct sk_buff))
1981
1982static inline void sk_stream_moderate_sndbuf(struct sock *sk)
1983{
1984 if (!(sk->sk_userlocks & SOCK_SNDBUF_LOCK)) {
1985 sk->sk_sndbuf = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
1986 sk->sk_sndbuf = max(sk->sk_sndbuf, SOCK_MIN_SNDBUF);
1987 }
1988}
1989
1990struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp);
1991
1992static inline struct page *sk_stream_alloc_page(struct sock *sk)
1993{
1994 struct page *page = NULL;
1995
1996 page = alloc_pages(sk->sk_allocation, 0);
1997 if (!page) {
1998 sk_enter_memory_pressure(sk);
1999 sk_stream_moderate_sndbuf(sk);
2000 }
2001 return page;
2002}
2003
2004/*
2005 * Default write policy as shown to user space via poll/select/SIGIO
2006 */
2007static inline bool sock_writeable(const struct sock *sk)
2008{
2009 return atomic_read(&sk->sk_wmem_alloc) < (sk->sk_sndbuf >> 1);
2010}
2011
2012static inline gfp_t gfp_any(void)
2013{
2014 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2015}
2016
2017static inline long sock_rcvtimeo(const struct sock *sk, bool noblock)
2018{
2019 return noblock ? 0 : sk->sk_rcvtimeo;
2020}
2021
2022static inline long sock_sndtimeo(const struct sock *sk, bool noblock)
2023{
2024 return noblock ? 0 : sk->sk_sndtimeo;
2025}
2026
2027static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
2028{
2029 return (waitall ? len : min_t(int, sk->sk_rcvlowat, len)) ? : 1;
2030}
2031
2032/* Alas, with timeout socket operations are not restartable.
2033 * Compare this to poll().
2034 */
2035static inline int sock_intr_errno(long timeo)
2036{
2037 return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
2038}
2039
2040extern void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
2041 struct sk_buff *skb);
2042extern void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
2043 struct sk_buff *skb);
2044
2045static inline void
2046sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
2047{
2048 ktime_t kt = skb->tstamp;
2049 struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
2050
2051 /*
2052 * generate control messages if
2053 * - receive time stamping in software requested (SOCK_RCVTSTAMP
2054 * or SOCK_TIMESTAMPING_RX_SOFTWARE)
2055 * - software time stamp available and wanted
2056 * (SOCK_TIMESTAMPING_SOFTWARE)
2057 * - hardware time stamps available and wanted
2058 * (SOCK_TIMESTAMPING_SYS_HARDWARE or
2059 * SOCK_TIMESTAMPING_RAW_HARDWARE)
2060 */
2061 if (sock_flag(sk, SOCK_RCVTSTAMP) ||
2062 sock_flag(sk, SOCK_TIMESTAMPING_RX_SOFTWARE) ||
2063 (kt.tv64 && sock_flag(sk, SOCK_TIMESTAMPING_SOFTWARE)) ||
2064 (hwtstamps->hwtstamp.tv64 &&
2065 sock_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE)) ||
2066 (hwtstamps->syststamp.tv64 &&
2067 sock_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE)))
2068 __sock_recv_timestamp(msg, sk, skb);
2069 else
2070 sk->sk_stamp = kt;
2071
2072 if (sock_flag(sk, SOCK_WIFI_STATUS) && skb->wifi_acked_valid)
2073 __sock_recv_wifi_status(msg, sk, skb);
2074}
2075
2076extern void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2077 struct sk_buff *skb);
2078
2079static inline void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2080 struct sk_buff *skb)
2081{
2082#define FLAGS_TS_OR_DROPS ((1UL << SOCK_RXQ_OVFL) | \
2083 (1UL << SOCK_RCVTSTAMP) | \
2084 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE) | \
2085 (1UL << SOCK_TIMESTAMPING_SOFTWARE) | \
2086 (1UL << SOCK_TIMESTAMPING_RAW_HARDWARE) | \
2087 (1UL << SOCK_TIMESTAMPING_SYS_HARDWARE))
2088
2089 if (sk->sk_flags & FLAGS_TS_OR_DROPS)
2090 __sock_recv_ts_and_drops(msg, sk, skb);
2091 else
2092 sk->sk_stamp = skb->tstamp;
2093}
2094
2095/**
2096 * sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
2097 * @sk: socket sending this packet
2098 * @tx_flags: filled with instructions for time stamping
2099 *
2100 * Currently only depends on SOCK_TIMESTAMPING* flags. Returns error code if
2101 * parameters are invalid.
2102 */
2103extern int sock_tx_timestamp(struct sock *sk, __u8 *tx_flags);
2104
2105/**
2106 * sk_eat_skb - Release a skb if it is no longer needed
2107 * @sk: socket to eat this skb from
2108 * @skb: socket buffer to eat
2109 * @copied_early: flag indicating whether DMA operations copied this data early
2110 *
2111 * This routine must be called with interrupts disabled or with the socket
2112 * locked so that the sk_buff queue operation is ok.
2113*/
2114#ifdef CONFIG_NET_DMA
2115static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb, bool copied_early)
2116{
2117 __skb_unlink(skb, &sk->sk_receive_queue);
2118 if (!copied_early)
2119 __kfree_skb(skb);
2120 else
2121 __skb_queue_tail(&sk->sk_async_wait_queue, skb);
2122}
2123#else
2124static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb, bool copied_early)
2125{
2126 __skb_unlink(skb, &sk->sk_receive_queue);
2127 __kfree_skb(skb);
2128}
2129#endif
2130
2131static inline
2132struct net *sock_net(const struct sock *sk)
2133{
2134 return read_pnet(&sk->sk_net);
2135}
2136
2137static inline
2138void sock_net_set(struct sock *sk, struct net *net)
2139{
2140 write_pnet(&sk->sk_net, net);
2141}
2142
2143/*
2144 * Kernel sockets, f.e. rtnl or icmp_socket, are a part of a namespace.
2145 * They should not hold a reference to a namespace in order to allow
2146 * to stop it.
2147 * Sockets after sk_change_net should be released using sk_release_kernel
2148 */
2149static inline void sk_change_net(struct sock *sk, struct net *net)
2150{
2151 put_net(sock_net(sk));
2152 sock_net_set(sk, hold_net(net));
2153}
2154
2155static inline struct sock *skb_steal_sock(struct sk_buff *skb)
2156{
2157 if (unlikely(skb->sk)) {
2158 struct sock *sk = skb->sk;
2159
2160 skb->destructor = NULL;
2161 skb->sk = NULL;
2162 return sk;
2163 }
2164 return NULL;
2165}
2166
2167extern void sock_enable_timestamp(struct sock *sk, int flag);
2168extern int sock_get_timestamp(struct sock *, struct timeval __user *);
2169extern int sock_get_timestampns(struct sock *, struct timespec __user *);
2170
2171/*
2172 * Enable debug/info messages
2173 */
2174extern int net_msg_warn;
2175#define NETDEBUG(fmt, args...) \
2176 do { if (net_msg_warn) printk(fmt,##args); } while (0)
2177
2178#define LIMIT_NETDEBUG(fmt, args...) \
2179 do { if (net_msg_warn && net_ratelimit()) printk(fmt,##args); } while(0)
2180
2181extern __u32 sysctl_wmem_max;
2182extern __u32 sysctl_rmem_max;
2183
2184extern void sk_init(void);
2185
2186extern int sysctl_optmem_max;
2187
2188extern __u32 sysctl_wmem_default;
2189extern __u32 sysctl_rmem_default;
2190
2191#endif /* _SOCK_H */