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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
129typedef __u32 __bitwise __portpair;
130typedef __u64 __bitwise __addrpair;
131
132/**
133 * struct sock_common - minimal network layer representation of sockets
134 * @skc_daddr: Foreign IPv4 addr
135 * @skc_rcv_saddr: Bound local IPv4 addr
136 * @skc_hash: hash value used with various protocol lookup tables
137 * @skc_u16hashes: two u16 hash values used by UDP lookup tables
138 * @skc_dport: placeholder for inet_dport/tw_dport
139 * @skc_num: placeholder for inet_num/tw_num
140 * @skc_family: network address family
141 * @skc_state: Connection state
142 * @skc_reuse: %SO_REUSEADDR setting
143 * @skc_reuseport: %SO_REUSEPORT setting
144 * @skc_bound_dev_if: bound device index if != 0
145 * @skc_bind_node: bind hash linkage for various protocol lookup tables
146 * @skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol
147 * @skc_prot: protocol handlers inside a network family
148 * @skc_net: reference to the network namespace of this socket
149 * @skc_node: main hash linkage for various protocol lookup tables
150 * @skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol
151 * @skc_tx_queue_mapping: tx queue number for this connection
152 * @skc_refcnt: reference count
153 *
154 * This is the minimal network layer representation of sockets, the header
155 * for struct sock and struct inet_timewait_sock.
156 */
157struct sock_common {
158 /* skc_daddr and skc_rcv_saddr must be grouped on a 8 bytes aligned
159 * address on 64bit arches : cf INET_MATCH()
160 */
161 union {
162 __addrpair skc_addrpair;
163 struct {
164 __be32 skc_daddr;
165 __be32 skc_rcv_saddr;
166 };
167 };
168 union {
169 unsigned int skc_hash;
170 __u16 skc_u16hashes[2];
171 };
172 /* skc_dport && skc_num must be grouped as well */
173 union {
174 __portpair skc_portpair;
175 struct {
176 __be16 skc_dport;
177 __u16 skc_num;
178 };
179 };
180
181 unsigned short skc_family;
182 volatile unsigned char skc_state;
183 unsigned char skc_reuse:4;
184 unsigned char skc_reuseport:4;
185 int skc_bound_dev_if;
186 union {
187 struct hlist_node skc_bind_node;
188 struct hlist_nulls_node skc_portaddr_node;
189 };
190 struct proto *skc_prot;
191#ifdef CONFIG_NET_NS
192 struct net *skc_net;
193#endif
194
195#if IS_ENABLED(CONFIG_IPV6)
196 struct in6_addr skc_v6_daddr;
197 struct in6_addr skc_v6_rcv_saddr;
198#endif
199
200 /*
201 * fields between dontcopy_begin/dontcopy_end
202 * are not copied in sock_copy()
203 */
204 /* private: */
205 int skc_dontcopy_begin[0];
206 /* public: */
207 union {
208 struct hlist_node skc_node;
209 struct hlist_nulls_node skc_nulls_node;
210 };
211 int skc_tx_queue_mapping;
212 atomic_t skc_refcnt;
213 /* private: */
214 int skc_dontcopy_end[0];
215 /* public: */
216};
217
218struct cg_proto;
219/**
220 * struct sock - network layer representation of sockets
221 * @__sk_common: shared layout with inet_timewait_sock
222 * @sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
223 * @sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
224 * @sk_lock: synchronizer
225 * @sk_rcvbuf: size of receive buffer in bytes
226 * @sk_wq: sock wait queue and async head
227 * @sk_rx_dst: receive input route used by early demux
228 * @sk_dst_cache: destination cache
229 * @sk_dst_lock: destination cache lock
230 * @sk_policy: flow policy
231 * @sk_receive_queue: incoming packets
232 * @sk_wmem_alloc: transmit queue bytes committed
233 * @sk_write_queue: Packet sending queue
234 * @sk_async_wait_queue: DMA copied packets
235 * @sk_omem_alloc: "o" is "option" or "other"
236 * @sk_wmem_queued: persistent queue size
237 * @sk_forward_alloc: space allocated forward
238 * @sk_napi_id: id of the last napi context to receive data for sk
239 * @sk_ll_usec: usecs to busypoll when there is no data
240 * @sk_allocation: allocation mode
241 * @sk_pacing_rate: Pacing rate (if supported by transport/packet scheduler)
242 * @sk_max_pacing_rate: Maximum pacing rate (%SO_MAX_PACING_RATE)
243 * @sk_sndbuf: size of send buffer in bytes
244 * @sk_flags: %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE,
245 * %SO_OOBINLINE settings, %SO_TIMESTAMPING settings
246 * @sk_no_check: %SO_NO_CHECK setting, whether or not checkup packets
247 * @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
248 * @sk_route_nocaps: forbidden route capabilities (e.g NETIF_F_GSO_MASK)
249 * @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
250 * @sk_gso_max_size: Maximum GSO segment size to build
251 * @sk_gso_max_segs: Maximum number of GSO segments
252 * @sk_lingertime: %SO_LINGER l_linger setting
253 * @sk_backlog: always used with the per-socket spinlock held
254 * @sk_callback_lock: used with the callbacks in the end of this struct
255 * @sk_error_queue: rarely used
256 * @sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt,
257 * IPV6_ADDRFORM for instance)
258 * @sk_err: last error
259 * @sk_err_soft: errors that don't cause failure but are the cause of a
260 * persistent failure not just 'timed out'
261 * @sk_drops: raw/udp drops counter
262 * @sk_ack_backlog: current listen backlog
263 * @sk_max_ack_backlog: listen backlog set in listen()
264 * @sk_priority: %SO_PRIORITY setting
265 * @sk_cgrp_prioidx: socket group's priority map index
266 * @sk_type: socket type (%SOCK_STREAM, etc)
267 * @sk_protocol: which protocol this socket belongs in this network family
268 * @sk_peer_pid: &struct pid for this socket's peer
269 * @sk_peer_cred: %SO_PEERCRED setting
270 * @sk_rcvlowat: %SO_RCVLOWAT setting
271 * @sk_rcvtimeo: %SO_RCVTIMEO setting
272 * @sk_sndtimeo: %SO_SNDTIMEO setting
273 * @sk_rxhash: flow hash received from netif layer
274 * @sk_filter: socket filtering instructions
275 * @sk_protinfo: private area, net family specific, when not using slab
276 * @sk_timer: sock cleanup timer
277 * @sk_stamp: time stamp of last packet received
278 * @sk_socket: Identd and reporting IO signals
279 * @sk_user_data: RPC layer private data
280 * @sk_frag: cached page frag
281 * @sk_peek_off: current peek_offset value
282 * @sk_send_head: front of stuff to transmit
283 * @sk_security: used by security modules
284 * @sk_mark: generic packet mark
285 * @sk_classid: this socket's cgroup classid
286 * @sk_cgrp: this socket's cgroup-specific proto data
287 * @sk_write_pending: a write to stream socket waits to start
288 * @sk_state_change: callback to indicate change in the state of the sock
289 * @sk_data_ready: callback to indicate there is data to be processed
290 * @sk_write_space: callback to indicate there is bf sending space available
291 * @sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
292 * @sk_backlog_rcv: callback to process the backlog
293 * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
294 */
295struct sock {
296 /*
297 * Now struct inet_timewait_sock also uses sock_common, so please just
298 * don't add nothing before this first member (__sk_common) --acme
299 */
300 struct sock_common __sk_common;
301#define sk_node __sk_common.skc_node
302#define sk_nulls_node __sk_common.skc_nulls_node
303#define sk_refcnt __sk_common.skc_refcnt
304#define sk_tx_queue_mapping __sk_common.skc_tx_queue_mapping
305
306#define sk_dontcopy_begin __sk_common.skc_dontcopy_begin
307#define sk_dontcopy_end __sk_common.skc_dontcopy_end
308#define sk_hash __sk_common.skc_hash
309#define sk_portpair __sk_common.skc_portpair
310#define sk_num __sk_common.skc_num
311#define sk_dport __sk_common.skc_dport
312#define sk_addrpair __sk_common.skc_addrpair
313#define sk_daddr __sk_common.skc_daddr
314#define sk_rcv_saddr __sk_common.skc_rcv_saddr
315#define sk_family __sk_common.skc_family
316#define sk_state __sk_common.skc_state
317#define sk_reuse __sk_common.skc_reuse
318#define sk_reuseport __sk_common.skc_reuseport
319#define sk_bound_dev_if __sk_common.skc_bound_dev_if
320#define sk_bind_node __sk_common.skc_bind_node
321#define sk_prot __sk_common.skc_prot
322#define sk_net __sk_common.skc_net
323#define sk_v6_daddr __sk_common.skc_v6_daddr
324#define sk_v6_rcv_saddr __sk_common.skc_v6_rcv_saddr
325
326 socket_lock_t sk_lock;
327 struct sk_buff_head sk_receive_queue;
328 /*
329 * The backlog queue is special, it is always used with
330 * the per-socket spinlock held and requires low latency
331 * access. Therefore we special case it's implementation.
332 * Note : rmem_alloc is in this structure to fill a hole
333 * on 64bit arches, not because its logically part of
334 * backlog.
335 */
336 struct {
337 atomic_t rmem_alloc;
338 int len;
339 struct sk_buff *head;
340 struct sk_buff *tail;
341 } sk_backlog;
342#define sk_rmem_alloc sk_backlog.rmem_alloc
343 int sk_forward_alloc;
344#ifdef CONFIG_RPS
345 __u32 sk_rxhash;
346#endif
347#ifdef CONFIG_NET_RX_BUSY_POLL
348 unsigned int sk_napi_id;
349 unsigned int sk_ll_usec;
350#endif
351 atomic_t sk_drops;
352 int sk_rcvbuf;
353
354 struct sk_filter __rcu *sk_filter;
355 struct socket_wq __rcu *sk_wq;
356
357#ifdef CONFIG_NET_DMA
358 struct sk_buff_head sk_async_wait_queue;
359#endif
360
361#ifdef CONFIG_XFRM
362 struct xfrm_policy *sk_policy[2];
363#endif
364 unsigned long sk_flags;
365 struct dst_entry *sk_rx_dst;
366 struct dst_entry __rcu *sk_dst_cache;
367 spinlock_t sk_dst_lock;
368 atomic_t sk_wmem_alloc;
369 atomic_t sk_omem_alloc;
370 int sk_sndbuf;
371 struct sk_buff_head sk_write_queue;
372 kmemcheck_bitfield_begin(flags);
373 unsigned int sk_shutdown : 2,
374 sk_no_check : 2,
375 sk_userlocks : 4,
376 sk_protocol : 8,
377 sk_type : 16;
378 kmemcheck_bitfield_end(flags);
379 int sk_wmem_queued;
380 gfp_t sk_allocation;
381 u32 sk_pacing_rate; /* bytes per second */
382 u32 sk_max_pacing_rate;
383 netdev_features_t sk_route_caps;
384 netdev_features_t sk_route_nocaps;
385 int sk_gso_type;
386 unsigned int sk_gso_max_size;
387 u16 sk_gso_max_segs;
388 int sk_rcvlowat;
389 unsigned long sk_lingertime;
390 struct sk_buff_head sk_error_queue;
391 struct proto *sk_prot_creator;
392 rwlock_t sk_callback_lock;
393 int sk_err,
394 sk_err_soft;
395 unsigned short sk_ack_backlog;
396 unsigned short sk_max_ack_backlog;
397 __u32 sk_priority;
398#if IS_ENABLED(CONFIG_CGROUP_NET_PRIO)
399 __u32 sk_cgrp_prioidx;
400#endif
401 struct pid *sk_peer_pid;
402 const struct cred *sk_peer_cred;
403 long sk_rcvtimeo;
404 long sk_sndtimeo;
405 void *sk_protinfo;
406 struct timer_list sk_timer;
407 ktime_t sk_stamp;
408 struct socket *sk_socket;
409 void *sk_user_data;
410 struct page_frag sk_frag;
411 struct sk_buff *sk_send_head;
412 __s32 sk_peek_off;
413 int sk_write_pending;
414#ifdef CONFIG_SECURITY
415 void *sk_security;
416#endif
417 __u32 sk_mark;
418 u32 sk_classid;
419 struct cg_proto *sk_cgrp;
420 void (*sk_state_change)(struct sock *sk);
421 void (*sk_data_ready)(struct sock *sk);
422 void (*sk_write_space)(struct sock *sk);
423 void (*sk_error_report)(struct sock *sk);
424 int (*sk_backlog_rcv)(struct sock *sk,
425 struct sk_buff *skb);
426 void (*sk_destruct)(struct sock *sk);
427};
428
429#define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data)))
430
431#define rcu_dereference_sk_user_data(sk) rcu_dereference(__sk_user_data((sk)))
432#define rcu_assign_sk_user_data(sk, ptr) rcu_assign_pointer(__sk_user_data((sk)), ptr)
433
434/*
435 * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK
436 * or not whether his port will be reused by someone else. SK_FORCE_REUSE
437 * on a socket means that the socket will reuse everybody else's port
438 * without looking at the other's sk_reuse value.
439 */
440
441#define SK_NO_REUSE 0
442#define SK_CAN_REUSE 1
443#define SK_FORCE_REUSE 2
444
445static inline int sk_peek_offset(struct sock *sk, int flags)
446{
447 if ((flags & MSG_PEEK) && (sk->sk_peek_off >= 0))
448 return sk->sk_peek_off;
449 else
450 return 0;
451}
452
453static inline void sk_peek_offset_bwd(struct sock *sk, int val)
454{
455 if (sk->sk_peek_off >= 0) {
456 if (sk->sk_peek_off >= val)
457 sk->sk_peek_off -= val;
458 else
459 sk->sk_peek_off = 0;
460 }
461}
462
463static inline void sk_peek_offset_fwd(struct sock *sk, int val)
464{
465 if (sk->sk_peek_off >= 0)
466 sk->sk_peek_off += val;
467}
468
469/*
470 * Hashed lists helper routines
471 */
472static inline struct sock *sk_entry(const struct hlist_node *node)
473{
474 return hlist_entry(node, struct sock, sk_node);
475}
476
477static inline struct sock *__sk_head(const struct hlist_head *head)
478{
479 return hlist_entry(head->first, struct sock, sk_node);
480}
481
482static inline struct sock *sk_head(const struct hlist_head *head)
483{
484 return hlist_empty(head) ? NULL : __sk_head(head);
485}
486
487static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head)
488{
489 return hlist_nulls_entry(head->first, struct sock, sk_nulls_node);
490}
491
492static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head)
493{
494 return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head);
495}
496
497static inline struct sock *sk_next(const struct sock *sk)
498{
499 return sk->sk_node.next ?
500 hlist_entry(sk->sk_node.next, struct sock, sk_node) : NULL;
501}
502
503static inline struct sock *sk_nulls_next(const struct sock *sk)
504{
505 return (!is_a_nulls(sk->sk_nulls_node.next)) ?
506 hlist_nulls_entry(sk->sk_nulls_node.next,
507 struct sock, sk_nulls_node) :
508 NULL;
509}
510
511static inline bool sk_unhashed(const struct sock *sk)
512{
513 return hlist_unhashed(&sk->sk_node);
514}
515
516static inline bool sk_hashed(const struct sock *sk)
517{
518 return !sk_unhashed(sk);
519}
520
521static inline void sk_node_init(struct hlist_node *node)
522{
523 node->pprev = NULL;
524}
525
526static inline void sk_nulls_node_init(struct hlist_nulls_node *node)
527{
528 node->pprev = NULL;
529}
530
531static inline void __sk_del_node(struct sock *sk)
532{
533 __hlist_del(&sk->sk_node);
534}
535
536/* NB: equivalent to hlist_del_init_rcu */
537static inline bool __sk_del_node_init(struct sock *sk)
538{
539 if (sk_hashed(sk)) {
540 __sk_del_node(sk);
541 sk_node_init(&sk->sk_node);
542 return true;
543 }
544 return false;
545}
546
547/* Grab socket reference count. This operation is valid only
548 when sk is ALREADY grabbed f.e. it is found in hash table
549 or a list and the lookup is made under lock preventing hash table
550 modifications.
551 */
552
553static inline void sock_hold(struct sock *sk)
554{
555 atomic_inc(&sk->sk_refcnt);
556}
557
558/* Ungrab socket in the context, which assumes that socket refcnt
559 cannot hit zero, f.e. it is true in context of any socketcall.
560 */
561static inline void __sock_put(struct sock *sk)
562{
563 atomic_dec(&sk->sk_refcnt);
564}
565
566static inline bool sk_del_node_init(struct sock *sk)
567{
568 bool rc = __sk_del_node_init(sk);
569
570 if (rc) {
571 /* paranoid for a while -acme */
572 WARN_ON(atomic_read(&sk->sk_refcnt) == 1);
573 __sock_put(sk);
574 }
575 return rc;
576}
577#define sk_del_node_init_rcu(sk) sk_del_node_init(sk)
578
579static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk)
580{
581 if (sk_hashed(sk)) {
582 hlist_nulls_del_init_rcu(&sk->sk_nulls_node);
583 return true;
584 }
585 return false;
586}
587
588static inline bool sk_nulls_del_node_init_rcu(struct sock *sk)
589{
590 bool rc = __sk_nulls_del_node_init_rcu(sk);
591
592 if (rc) {
593 /* paranoid for a while -acme */
594 WARN_ON(atomic_read(&sk->sk_refcnt) == 1);
595 __sock_put(sk);
596 }
597 return rc;
598}
599
600static inline void __sk_add_node(struct sock *sk, struct hlist_head *list)
601{
602 hlist_add_head(&sk->sk_node, list);
603}
604
605static inline void sk_add_node(struct sock *sk, struct hlist_head *list)
606{
607 sock_hold(sk);
608 __sk_add_node(sk, list);
609}
610
611static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list)
612{
613 sock_hold(sk);
614 hlist_add_head_rcu(&sk->sk_node, list);
615}
616
617static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
618{
619 hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list);
620}
621
622static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
623{
624 sock_hold(sk);
625 __sk_nulls_add_node_rcu(sk, list);
626}
627
628static inline void __sk_del_bind_node(struct sock *sk)
629{
630 __hlist_del(&sk->sk_bind_node);
631}
632
633static inline void sk_add_bind_node(struct sock *sk,
634 struct hlist_head *list)
635{
636 hlist_add_head(&sk->sk_bind_node, list);
637}
638
639#define sk_for_each(__sk, list) \
640 hlist_for_each_entry(__sk, list, sk_node)
641#define sk_for_each_rcu(__sk, list) \
642 hlist_for_each_entry_rcu(__sk, list, sk_node)
643#define sk_nulls_for_each(__sk, node, list) \
644 hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)
645#define sk_nulls_for_each_rcu(__sk, node, list) \
646 hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)
647#define sk_for_each_from(__sk) \
648 hlist_for_each_entry_from(__sk, sk_node)
649#define sk_nulls_for_each_from(__sk, node) \
650 if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \
651 hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node)
652#define sk_for_each_safe(__sk, tmp, list) \
653 hlist_for_each_entry_safe(__sk, tmp, list, sk_node)
654#define sk_for_each_bound(__sk, list) \
655 hlist_for_each_entry(__sk, list, sk_bind_node)
656
657static inline struct user_namespace *sk_user_ns(struct sock *sk)
658{
659 /* Careful only use this in a context where these parameters
660 * can not change and must all be valid, such as recvmsg from
661 * userspace.
662 */
663 return sk->sk_socket->file->f_cred->user_ns;
664}
665
666/* Sock flags */
667enum sock_flags {
668 SOCK_DEAD,
669 SOCK_DONE,
670 SOCK_URGINLINE,
671 SOCK_KEEPOPEN,
672 SOCK_LINGER,
673 SOCK_DESTROY,
674 SOCK_BROADCAST,
675 SOCK_TIMESTAMP,
676 SOCK_ZAPPED,
677 SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */
678 SOCK_DBG, /* %SO_DEBUG setting */
679 SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
680 SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */
681 SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
682 SOCK_QUEUE_SHRUNK, /* write queue has been shrunk recently */
683 SOCK_MEMALLOC, /* VM depends on this socket for swapping */
684 SOCK_TIMESTAMPING_TX_HARDWARE, /* %SOF_TIMESTAMPING_TX_HARDWARE */
685 SOCK_TIMESTAMPING_TX_SOFTWARE, /* %SOF_TIMESTAMPING_TX_SOFTWARE */
686 SOCK_TIMESTAMPING_RX_HARDWARE, /* %SOF_TIMESTAMPING_RX_HARDWARE */
687 SOCK_TIMESTAMPING_RX_SOFTWARE, /* %SOF_TIMESTAMPING_RX_SOFTWARE */
688 SOCK_TIMESTAMPING_SOFTWARE, /* %SOF_TIMESTAMPING_SOFTWARE */
689 SOCK_TIMESTAMPING_RAW_HARDWARE, /* %SOF_TIMESTAMPING_RAW_HARDWARE */
690 SOCK_TIMESTAMPING_SYS_HARDWARE, /* %SOF_TIMESTAMPING_SYS_HARDWARE */
691 SOCK_FASYNC, /* fasync() active */
692 SOCK_RXQ_OVFL,
693 SOCK_ZEROCOPY, /* buffers from userspace */
694 SOCK_WIFI_STATUS, /* push wifi status to userspace */
695 SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS.
696 * Will use last 4 bytes of packet sent from
697 * user-space instead.
698 */
699 SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */
700 SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */
701};
702
703static inline void sock_copy_flags(struct sock *nsk, struct sock *osk)
704{
705 nsk->sk_flags = osk->sk_flags;
706}
707
708static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
709{
710 __set_bit(flag, &sk->sk_flags);
711}
712
713static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag)
714{
715 __clear_bit(flag, &sk->sk_flags);
716}
717
718static inline bool sock_flag(const struct sock *sk, enum sock_flags flag)
719{
720 return test_bit(flag, &sk->sk_flags);
721}
722
723#ifdef CONFIG_NET
724extern struct static_key memalloc_socks;
725static inline int sk_memalloc_socks(void)
726{
727 return static_key_false(&memalloc_socks);
728}
729#else
730
731static inline int sk_memalloc_socks(void)
732{
733 return 0;
734}
735
736#endif
737
738static inline gfp_t sk_gfp_atomic(struct sock *sk, gfp_t gfp_mask)
739{
740 return GFP_ATOMIC | (sk->sk_allocation & __GFP_MEMALLOC);
741}
742
743static inline void sk_acceptq_removed(struct sock *sk)
744{
745 sk->sk_ack_backlog--;
746}
747
748static inline void sk_acceptq_added(struct sock *sk)
749{
750 sk->sk_ack_backlog++;
751}
752
753static inline bool sk_acceptq_is_full(const struct sock *sk)
754{
755 return sk->sk_ack_backlog > sk->sk_max_ack_backlog;
756}
757
758/*
759 * Compute minimal free write space needed to queue new packets.
760 */
761static inline int sk_stream_min_wspace(const struct sock *sk)
762{
763 return sk->sk_wmem_queued >> 1;
764}
765
766static inline int sk_stream_wspace(const struct sock *sk)
767{
768 return sk->sk_sndbuf - sk->sk_wmem_queued;
769}
770
771void sk_stream_write_space(struct sock *sk);
772
773/* OOB backlog add */
774static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
775{
776 /* dont let skb dst not refcounted, we are going to leave rcu lock */
777 skb_dst_force(skb);
778
779 if (!sk->sk_backlog.tail)
780 sk->sk_backlog.head = skb;
781 else
782 sk->sk_backlog.tail->next = skb;
783
784 sk->sk_backlog.tail = skb;
785 skb->next = NULL;
786}
787
788/*
789 * Take into account size of receive queue and backlog queue
790 * Do not take into account this skb truesize,
791 * to allow even a single big packet to come.
792 */
793static inline bool sk_rcvqueues_full(const struct sock *sk, const struct sk_buff *skb,
794 unsigned int limit)
795{
796 unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc);
797
798 return qsize > limit;
799}
800
801/* The per-socket spinlock must be held here. */
802static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb,
803 unsigned int limit)
804{
805 if (sk_rcvqueues_full(sk, skb, limit))
806 return -ENOBUFS;
807
808 __sk_add_backlog(sk, skb);
809 sk->sk_backlog.len += skb->truesize;
810 return 0;
811}
812
813int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb);
814
815static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
816{
817 if (sk_memalloc_socks() && skb_pfmemalloc(skb))
818 return __sk_backlog_rcv(sk, skb);
819
820 return sk->sk_backlog_rcv(sk, skb);
821}
822
823static inline void sock_rps_record_flow_hash(__u32 hash)
824{
825#ifdef CONFIG_RPS
826 struct rps_sock_flow_table *sock_flow_table;
827
828 rcu_read_lock();
829 sock_flow_table = rcu_dereference(rps_sock_flow_table);
830 rps_record_sock_flow(sock_flow_table, hash);
831 rcu_read_unlock();
832#endif
833}
834
835static inline void sock_rps_reset_flow_hash(__u32 hash)
836{
837#ifdef CONFIG_RPS
838 struct rps_sock_flow_table *sock_flow_table;
839
840 rcu_read_lock();
841 sock_flow_table = rcu_dereference(rps_sock_flow_table);
842 rps_reset_sock_flow(sock_flow_table, hash);
843 rcu_read_unlock();
844#endif
845}
846
847static inline void sock_rps_record_flow(const struct sock *sk)
848{
849#ifdef CONFIG_RPS
850 sock_rps_record_flow_hash(sk->sk_rxhash);
851#endif
852}
853
854static inline void sock_rps_reset_flow(const struct sock *sk)
855{
856#ifdef CONFIG_RPS
857 sock_rps_reset_flow_hash(sk->sk_rxhash);
858#endif
859}
860
861static inline void sock_rps_save_rxhash(struct sock *sk,
862 const struct sk_buff *skb)
863{
864#ifdef CONFIG_RPS
865 if (unlikely(sk->sk_rxhash != skb->hash)) {
866 sock_rps_reset_flow(sk);
867 sk->sk_rxhash = skb->hash;
868 }
869#endif
870}
871
872static inline void sock_rps_reset_rxhash(struct sock *sk)
873{
874#ifdef CONFIG_RPS
875 sock_rps_reset_flow(sk);
876 sk->sk_rxhash = 0;
877#endif
878}
879
880#define sk_wait_event(__sk, __timeo, __condition) \
881 ({ int __rc; \
882 release_sock(__sk); \
883 __rc = __condition; \
884 if (!__rc) { \
885 *(__timeo) = schedule_timeout(*(__timeo)); \
886 } \
887 lock_sock(__sk); \
888 __rc = __condition; \
889 __rc; \
890 })
891
892int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
893int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
894void sk_stream_wait_close(struct sock *sk, long timeo_p);
895int sk_stream_error(struct sock *sk, int flags, int err);
896void sk_stream_kill_queues(struct sock *sk);
897void sk_set_memalloc(struct sock *sk);
898void sk_clear_memalloc(struct sock *sk);
899
900int sk_wait_data(struct sock *sk, long *timeo);
901
902struct request_sock_ops;
903struct timewait_sock_ops;
904struct inet_hashinfo;
905struct raw_hashinfo;
906struct module;
907
908/*
909 * caches using SLAB_DESTROY_BY_RCU should let .next pointer from nulls nodes
910 * un-modified. Special care is taken when initializing object to zero.
911 */
912static inline void sk_prot_clear_nulls(struct sock *sk, int size)
913{
914 if (offsetof(struct sock, sk_node.next) != 0)
915 memset(sk, 0, offsetof(struct sock, sk_node.next));
916 memset(&sk->sk_node.pprev, 0,
917 size - offsetof(struct sock, sk_node.pprev));
918}
919
920/* Networking protocol blocks we attach to sockets.
921 * socket layer -> transport layer interface
922 * transport -> network interface is defined by struct inet_proto
923 */
924struct proto {
925 void (*close)(struct sock *sk,
926 long timeout);
927 int (*connect)(struct sock *sk,
928 struct sockaddr *uaddr,
929 int addr_len);
930 int (*disconnect)(struct sock *sk, int flags);
931
932 struct sock * (*accept)(struct sock *sk, int flags, int *err);
933
934 int (*ioctl)(struct sock *sk, int cmd,
935 unsigned long arg);
936 int (*init)(struct sock *sk);
937 void (*destroy)(struct sock *sk);
938 void (*shutdown)(struct sock *sk, int how);
939 int (*setsockopt)(struct sock *sk, int level,
940 int optname, char __user *optval,
941 unsigned int optlen);
942 int (*getsockopt)(struct sock *sk, int level,
943 int optname, char __user *optval,
944 int __user *option);
945#ifdef CONFIG_COMPAT
946 int (*compat_setsockopt)(struct sock *sk,
947 int level,
948 int optname, char __user *optval,
949 unsigned int optlen);
950 int (*compat_getsockopt)(struct sock *sk,
951 int level,
952 int optname, char __user *optval,
953 int __user *option);
954 int (*compat_ioctl)(struct sock *sk,
955 unsigned int cmd, unsigned long arg);
956#endif
957 int (*sendmsg)(struct kiocb *iocb, struct sock *sk,
958 struct msghdr *msg, size_t len);
959 int (*recvmsg)(struct kiocb *iocb, struct sock *sk,
960 struct msghdr *msg,
961 size_t len, int noblock, int flags,
962 int *addr_len);
963 int (*sendpage)(struct sock *sk, struct page *page,
964 int offset, size_t size, int flags);
965 int (*bind)(struct sock *sk,
966 struct sockaddr *uaddr, int addr_len);
967
968 int (*backlog_rcv) (struct sock *sk,
969 struct sk_buff *skb);
970
971 void (*release_cb)(struct sock *sk);
972 void (*mtu_reduced)(struct sock *sk);
973
974 /* Keeping track of sk's, looking them up, and port selection methods. */
975 void (*hash)(struct sock *sk);
976 void (*unhash)(struct sock *sk);
977 void (*rehash)(struct sock *sk);
978 int (*get_port)(struct sock *sk, unsigned short snum);
979 void (*clear_sk)(struct sock *sk, int size);
980
981 /* Keeping track of sockets in use */
982#ifdef CONFIG_PROC_FS
983 unsigned int inuse_idx;
984#endif
985
986 bool (*stream_memory_free)(const struct sock *sk);
987 /* Memory pressure */
988 void (*enter_memory_pressure)(struct sock *sk);
989 atomic_long_t *memory_allocated; /* Current allocated memory. */
990 struct percpu_counter *sockets_allocated; /* Current number of sockets. */
991 /*
992 * Pressure flag: try to collapse.
993 * Technical note: it is used by multiple contexts non atomically.
994 * All the __sk_mem_schedule() is of this nature: accounting
995 * is strict, actions are advisory and have some latency.
996 */
997 int *memory_pressure;
998 long *sysctl_mem;
999 int *sysctl_wmem;
1000 int *sysctl_rmem;
1001 int max_header;
1002 bool no_autobind;
1003
1004 struct kmem_cache *slab;
1005 unsigned int obj_size;
1006 int slab_flags;
1007
1008 struct percpu_counter *orphan_count;
1009
1010 struct request_sock_ops *rsk_prot;
1011 struct timewait_sock_ops *twsk_prot;
1012
1013 union {
1014 struct inet_hashinfo *hashinfo;
1015 struct udp_table *udp_table;
1016 struct raw_hashinfo *raw_hash;
1017 } h;
1018
1019 struct module *owner;
1020
1021 char name[32];
1022
1023 struct list_head node;
1024#ifdef SOCK_REFCNT_DEBUG
1025 atomic_t socks;
1026#endif
1027#ifdef CONFIG_MEMCG_KMEM
1028 /*
1029 * cgroup specific init/deinit functions. Called once for all
1030 * protocols that implement it, from cgroups populate function.
1031 * This function has to setup any files the protocol want to
1032 * appear in the kmem cgroup filesystem.
1033 */
1034 int (*init_cgroup)(struct mem_cgroup *memcg,
1035 struct cgroup_subsys *ss);
1036 void (*destroy_cgroup)(struct mem_cgroup *memcg);
1037 struct cg_proto *(*proto_cgroup)(struct mem_cgroup *memcg);
1038#endif
1039};
1040
1041/*
1042 * Bits in struct cg_proto.flags
1043 */
1044enum cg_proto_flags {
1045 /* Currently active and new sockets should be assigned to cgroups */
1046 MEMCG_SOCK_ACTIVE,
1047 /* It was ever activated; we must disarm static keys on destruction */
1048 MEMCG_SOCK_ACTIVATED,
1049};
1050
1051struct cg_proto {
1052 struct res_counter memory_allocated; /* Current allocated memory. */
1053 struct percpu_counter sockets_allocated; /* Current number of sockets. */
1054 int memory_pressure;
1055 long sysctl_mem[3];
1056 unsigned long flags;
1057 /*
1058 * memcg field is used to find which memcg we belong directly
1059 * Each memcg struct can hold more than one cg_proto, so container_of
1060 * won't really cut.
1061 *
1062 * The elegant solution would be having an inverse function to
1063 * proto_cgroup in struct proto, but that means polluting the structure
1064 * for everybody, instead of just for memcg users.
1065 */
1066 struct mem_cgroup *memcg;
1067};
1068
1069int proto_register(struct proto *prot, int alloc_slab);
1070void proto_unregister(struct proto *prot);
1071
1072static inline bool memcg_proto_active(struct cg_proto *cg_proto)
1073{
1074 return test_bit(MEMCG_SOCK_ACTIVE, &cg_proto->flags);
1075}
1076
1077static inline bool memcg_proto_activated(struct cg_proto *cg_proto)
1078{
1079 return test_bit(MEMCG_SOCK_ACTIVATED, &cg_proto->flags);
1080}
1081
1082#ifdef SOCK_REFCNT_DEBUG
1083static inline void sk_refcnt_debug_inc(struct sock *sk)
1084{
1085 atomic_inc(&sk->sk_prot->socks);
1086}
1087
1088static inline void sk_refcnt_debug_dec(struct sock *sk)
1089{
1090 atomic_dec(&sk->sk_prot->socks);
1091 printk(KERN_DEBUG "%s socket %p released, %d are still alive\n",
1092 sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks));
1093}
1094
1095static inline void sk_refcnt_debug_release(const struct sock *sk)
1096{
1097 if (atomic_read(&sk->sk_refcnt) != 1)
1098 printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n",
1099 sk->sk_prot->name, sk, atomic_read(&sk->sk_refcnt));
1100}
1101#else /* SOCK_REFCNT_DEBUG */
1102#define sk_refcnt_debug_inc(sk) do { } while (0)
1103#define sk_refcnt_debug_dec(sk) do { } while (0)
1104#define sk_refcnt_debug_release(sk) do { } while (0)
1105#endif /* SOCK_REFCNT_DEBUG */
1106
1107#if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_NET)
1108extern struct static_key memcg_socket_limit_enabled;
1109static inline struct cg_proto *parent_cg_proto(struct proto *proto,
1110 struct cg_proto *cg_proto)
1111{
1112 return proto->proto_cgroup(parent_mem_cgroup(cg_proto->memcg));
1113}
1114#define mem_cgroup_sockets_enabled static_key_false(&memcg_socket_limit_enabled)
1115#else
1116#define mem_cgroup_sockets_enabled 0
1117static inline struct cg_proto *parent_cg_proto(struct proto *proto,
1118 struct cg_proto *cg_proto)
1119{
1120 return NULL;
1121}
1122#endif
1123
1124static inline bool sk_stream_memory_free(const struct sock *sk)
1125{
1126 if (sk->sk_wmem_queued >= sk->sk_sndbuf)
1127 return false;
1128
1129 return sk->sk_prot->stream_memory_free ?
1130 sk->sk_prot->stream_memory_free(sk) : true;
1131}
1132
1133static inline bool sk_stream_is_writeable(const struct sock *sk)
1134{
1135 return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) &&
1136 sk_stream_memory_free(sk);
1137}
1138
1139
1140static inline bool sk_has_memory_pressure(const struct sock *sk)
1141{
1142 return sk->sk_prot->memory_pressure != NULL;
1143}
1144
1145static inline bool sk_under_memory_pressure(const struct sock *sk)
1146{
1147 if (!sk->sk_prot->memory_pressure)
1148 return false;
1149
1150 if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1151 return !!sk->sk_cgrp->memory_pressure;
1152
1153 return !!*sk->sk_prot->memory_pressure;
1154}
1155
1156static inline void sk_leave_memory_pressure(struct sock *sk)
1157{
1158 int *memory_pressure = sk->sk_prot->memory_pressure;
1159
1160 if (!memory_pressure)
1161 return;
1162
1163 if (*memory_pressure)
1164 *memory_pressure = 0;
1165
1166 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1167 struct cg_proto *cg_proto = sk->sk_cgrp;
1168 struct proto *prot = sk->sk_prot;
1169
1170 for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto))
1171 cg_proto->memory_pressure = 0;
1172 }
1173
1174}
1175
1176static inline void sk_enter_memory_pressure(struct sock *sk)
1177{
1178 if (!sk->sk_prot->enter_memory_pressure)
1179 return;
1180
1181 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1182 struct cg_proto *cg_proto = sk->sk_cgrp;
1183 struct proto *prot = sk->sk_prot;
1184
1185 for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto))
1186 cg_proto->memory_pressure = 1;
1187 }
1188
1189 sk->sk_prot->enter_memory_pressure(sk);
1190}
1191
1192static inline long sk_prot_mem_limits(const struct sock *sk, int index)
1193{
1194 long *prot = sk->sk_prot->sysctl_mem;
1195 if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1196 prot = sk->sk_cgrp->sysctl_mem;
1197 return prot[index];
1198}
1199
1200static inline void memcg_memory_allocated_add(struct cg_proto *prot,
1201 unsigned long amt,
1202 int *parent_status)
1203{
1204 struct res_counter *fail;
1205 int ret;
1206
1207 ret = res_counter_charge_nofail(&prot->memory_allocated,
1208 amt << PAGE_SHIFT, &fail);
1209 if (ret < 0)
1210 *parent_status = OVER_LIMIT;
1211}
1212
1213static inline void memcg_memory_allocated_sub(struct cg_proto *prot,
1214 unsigned long amt)
1215{
1216 res_counter_uncharge(&prot->memory_allocated, amt << PAGE_SHIFT);
1217}
1218
1219static inline u64 memcg_memory_allocated_read(struct cg_proto *prot)
1220{
1221 u64 ret;
1222 ret = res_counter_read_u64(&prot->memory_allocated, RES_USAGE);
1223 return ret >> PAGE_SHIFT;
1224}
1225
1226static inline long
1227sk_memory_allocated(const struct sock *sk)
1228{
1229 struct proto *prot = sk->sk_prot;
1230 if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1231 return memcg_memory_allocated_read(sk->sk_cgrp);
1232
1233 return atomic_long_read(prot->memory_allocated);
1234}
1235
1236static inline long
1237sk_memory_allocated_add(struct sock *sk, int amt, int *parent_status)
1238{
1239 struct proto *prot = sk->sk_prot;
1240
1241 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1242 memcg_memory_allocated_add(sk->sk_cgrp, amt, parent_status);
1243 /* update the root cgroup regardless */
1244 atomic_long_add_return(amt, prot->memory_allocated);
1245 return memcg_memory_allocated_read(sk->sk_cgrp);
1246 }
1247
1248 return atomic_long_add_return(amt, prot->memory_allocated);
1249}
1250
1251static inline void
1252sk_memory_allocated_sub(struct sock *sk, int amt)
1253{
1254 struct proto *prot = sk->sk_prot;
1255
1256 if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1257 memcg_memory_allocated_sub(sk->sk_cgrp, amt);
1258
1259 atomic_long_sub(amt, prot->memory_allocated);
1260}
1261
1262static inline void sk_sockets_allocated_dec(struct sock *sk)
1263{
1264 struct proto *prot = sk->sk_prot;
1265
1266 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1267 struct cg_proto *cg_proto = sk->sk_cgrp;
1268
1269 for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto))
1270 percpu_counter_dec(&cg_proto->sockets_allocated);
1271 }
1272
1273 percpu_counter_dec(prot->sockets_allocated);
1274}
1275
1276static inline void sk_sockets_allocated_inc(struct sock *sk)
1277{
1278 struct proto *prot = sk->sk_prot;
1279
1280 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1281 struct cg_proto *cg_proto = sk->sk_cgrp;
1282
1283 for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto))
1284 percpu_counter_inc(&cg_proto->sockets_allocated);
1285 }
1286
1287 percpu_counter_inc(prot->sockets_allocated);
1288}
1289
1290static inline int
1291sk_sockets_allocated_read_positive(struct sock *sk)
1292{
1293 struct proto *prot = sk->sk_prot;
1294
1295 if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1296 return percpu_counter_read_positive(&sk->sk_cgrp->sockets_allocated);
1297
1298 return percpu_counter_read_positive(prot->sockets_allocated);
1299}
1300
1301static inline int
1302proto_sockets_allocated_sum_positive(struct proto *prot)
1303{
1304 return percpu_counter_sum_positive(prot->sockets_allocated);
1305}
1306
1307static inline long
1308proto_memory_allocated(struct proto *prot)
1309{
1310 return atomic_long_read(prot->memory_allocated);
1311}
1312
1313static inline bool
1314proto_memory_pressure(struct proto *prot)
1315{
1316 if (!prot->memory_pressure)
1317 return false;
1318 return !!*prot->memory_pressure;
1319}
1320
1321
1322#ifdef CONFIG_PROC_FS
1323/* Called with local bh disabled */
1324void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc);
1325int sock_prot_inuse_get(struct net *net, struct proto *proto);
1326#else
1327static inline void sock_prot_inuse_add(struct net *net, struct proto *prot,
1328 int inc)
1329{
1330}
1331#endif
1332
1333
1334/* With per-bucket locks this operation is not-atomic, so that
1335 * this version is not worse.
1336 */
1337static inline void __sk_prot_rehash(struct sock *sk)
1338{
1339 sk->sk_prot->unhash(sk);
1340 sk->sk_prot->hash(sk);
1341}
1342
1343void sk_prot_clear_portaddr_nulls(struct sock *sk, int size);
1344
1345/* About 10 seconds */
1346#define SOCK_DESTROY_TIME (10*HZ)
1347
1348/* Sockets 0-1023 can't be bound to unless you are superuser */
1349#define PROT_SOCK 1024
1350
1351#define SHUTDOWN_MASK 3
1352#define RCV_SHUTDOWN 1
1353#define SEND_SHUTDOWN 2
1354
1355#define SOCK_SNDBUF_LOCK 1
1356#define SOCK_RCVBUF_LOCK 2
1357#define SOCK_BINDADDR_LOCK 4
1358#define SOCK_BINDPORT_LOCK 8
1359
1360/* sock_iocb: used to kick off async processing of socket ios */
1361struct sock_iocb {
1362 struct list_head list;
1363
1364 int flags;
1365 int size;
1366 struct socket *sock;
1367 struct sock *sk;
1368 struct scm_cookie *scm;
1369 struct msghdr *msg, async_msg;
1370 struct kiocb *kiocb;
1371};
1372
1373static inline struct sock_iocb *kiocb_to_siocb(struct kiocb *iocb)
1374{
1375 return (struct sock_iocb *)iocb->private;
1376}
1377
1378static inline struct kiocb *siocb_to_kiocb(struct sock_iocb *si)
1379{
1380 return si->kiocb;
1381}
1382
1383struct socket_alloc {
1384 struct socket socket;
1385 struct inode vfs_inode;
1386};
1387
1388static inline struct socket *SOCKET_I(struct inode *inode)
1389{
1390 return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
1391}
1392
1393static inline struct inode *SOCK_INODE(struct socket *socket)
1394{
1395 return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
1396}
1397
1398/*
1399 * Functions for memory accounting
1400 */
1401int __sk_mem_schedule(struct sock *sk, int size, int kind);
1402void __sk_mem_reclaim(struct sock *sk);
1403
1404#define SK_MEM_QUANTUM ((int)PAGE_SIZE)
1405#define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM)
1406#define SK_MEM_SEND 0
1407#define SK_MEM_RECV 1
1408
1409static inline int sk_mem_pages(int amt)
1410{
1411 return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT;
1412}
1413
1414static inline bool sk_has_account(struct sock *sk)
1415{
1416 /* return true if protocol supports memory accounting */
1417 return !!sk->sk_prot->memory_allocated;
1418}
1419
1420static inline bool sk_wmem_schedule(struct sock *sk, int size)
1421{
1422 if (!sk_has_account(sk))
1423 return true;
1424 return size <= sk->sk_forward_alloc ||
1425 __sk_mem_schedule(sk, size, SK_MEM_SEND);
1426}
1427
1428static inline bool
1429sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size)
1430{
1431 if (!sk_has_account(sk))
1432 return true;
1433 return size<= sk->sk_forward_alloc ||
1434 __sk_mem_schedule(sk, size, SK_MEM_RECV) ||
1435 skb_pfmemalloc(skb);
1436}
1437
1438static inline void sk_mem_reclaim(struct sock *sk)
1439{
1440 if (!sk_has_account(sk))
1441 return;
1442 if (sk->sk_forward_alloc >= SK_MEM_QUANTUM)
1443 __sk_mem_reclaim(sk);
1444}
1445
1446static inline void sk_mem_reclaim_partial(struct sock *sk)
1447{
1448 if (!sk_has_account(sk))
1449 return;
1450 if (sk->sk_forward_alloc > SK_MEM_QUANTUM)
1451 __sk_mem_reclaim(sk);
1452}
1453
1454static inline void sk_mem_charge(struct sock *sk, int size)
1455{
1456 if (!sk_has_account(sk))
1457 return;
1458 sk->sk_forward_alloc -= size;
1459}
1460
1461static inline void sk_mem_uncharge(struct sock *sk, int size)
1462{
1463 if (!sk_has_account(sk))
1464 return;
1465 sk->sk_forward_alloc += size;
1466}
1467
1468static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb)
1469{
1470 sock_set_flag(sk, SOCK_QUEUE_SHRUNK);
1471 sk->sk_wmem_queued -= skb->truesize;
1472 sk_mem_uncharge(sk, skb->truesize);
1473 __kfree_skb(skb);
1474}
1475
1476/* Used by processes to "lock" a socket state, so that
1477 * interrupts and bottom half handlers won't change it
1478 * from under us. It essentially blocks any incoming
1479 * packets, so that we won't get any new data or any
1480 * packets that change the state of the socket.
1481 *
1482 * While locked, BH processing will add new packets to
1483 * the backlog queue. This queue is processed by the
1484 * owner of the socket lock right before it is released.
1485 *
1486 * Since ~2.3.5 it is also exclusive sleep lock serializing
1487 * accesses from user process context.
1488 */
1489#define sock_owned_by_user(sk) ((sk)->sk_lock.owned)
1490
1491static inline void sock_release_ownership(struct sock *sk)
1492{
1493 sk->sk_lock.owned = 0;
1494}
1495
1496/*
1497 * Macro so as to not evaluate some arguments when
1498 * lockdep is not enabled.
1499 *
1500 * Mark both the sk_lock and the sk_lock.slock as a
1501 * per-address-family lock class.
1502 */
1503#define sock_lock_init_class_and_name(sk, sname, skey, name, key) \
1504do { \
1505 sk->sk_lock.owned = 0; \
1506 init_waitqueue_head(&sk->sk_lock.wq); \
1507 spin_lock_init(&(sk)->sk_lock.slock); \
1508 debug_check_no_locks_freed((void *)&(sk)->sk_lock, \
1509 sizeof((sk)->sk_lock)); \
1510 lockdep_set_class_and_name(&(sk)->sk_lock.slock, \
1511 (skey), (sname)); \
1512 lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \
1513} while (0)
1514
1515void lock_sock_nested(struct sock *sk, int subclass);
1516
1517static inline void lock_sock(struct sock *sk)
1518{
1519 lock_sock_nested(sk, 0);
1520}
1521
1522void release_sock(struct sock *sk);
1523
1524/* BH context may only use the following locking interface. */
1525#define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock))
1526#define bh_lock_sock_nested(__sk) \
1527 spin_lock_nested(&((__sk)->sk_lock.slock), \
1528 SINGLE_DEPTH_NESTING)
1529#define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock))
1530
1531bool lock_sock_fast(struct sock *sk);
1532/**
1533 * unlock_sock_fast - complement of lock_sock_fast
1534 * @sk: socket
1535 * @slow: slow mode
1536 *
1537 * fast unlock socket for user context.
1538 * If slow mode is on, we call regular release_sock()
1539 */
1540static inline void unlock_sock_fast(struct sock *sk, bool slow)
1541{
1542 if (slow)
1543 release_sock(sk);
1544 else
1545 spin_unlock_bh(&sk->sk_lock.slock);
1546}
1547
1548
1549struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1550 struct proto *prot);
1551void sk_free(struct sock *sk);
1552void sk_release_kernel(struct sock *sk);
1553struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority);
1554
1555struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1556 gfp_t priority);
1557void sock_wfree(struct sk_buff *skb);
1558void skb_orphan_partial(struct sk_buff *skb);
1559void sock_rfree(struct sk_buff *skb);
1560void sock_edemux(struct sk_buff *skb);
1561
1562int sock_setsockopt(struct socket *sock, int level, int op,
1563 char __user *optval, unsigned int optlen);
1564
1565int sock_getsockopt(struct socket *sock, int level, int op,
1566 char __user *optval, int __user *optlen);
1567struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1568 int noblock, int *errcode);
1569struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1570 unsigned long data_len, int noblock,
1571 int *errcode, int max_page_order);
1572void *sock_kmalloc(struct sock *sk, int size, gfp_t priority);
1573void sock_kfree_s(struct sock *sk, void *mem, int size);
1574void sk_send_sigurg(struct sock *sk);
1575
1576/*
1577 * Functions to fill in entries in struct proto_ops when a protocol
1578 * does not implement a particular function.
1579 */
1580int sock_no_bind(struct socket *, struct sockaddr *, int);
1581int sock_no_connect(struct socket *, struct sockaddr *, int, int);
1582int sock_no_socketpair(struct socket *, struct socket *);
1583int sock_no_accept(struct socket *, struct socket *, int);
1584int sock_no_getname(struct socket *, struct sockaddr *, int *, int);
1585unsigned int sock_no_poll(struct file *, struct socket *,
1586 struct poll_table_struct *);
1587int sock_no_ioctl(struct socket *, unsigned int, unsigned long);
1588int sock_no_listen(struct socket *, int);
1589int sock_no_shutdown(struct socket *, int);
1590int sock_no_getsockopt(struct socket *, int , int, char __user *, int __user *);
1591int sock_no_setsockopt(struct socket *, int, int, char __user *, unsigned int);
1592int sock_no_sendmsg(struct kiocb *, struct socket *, struct msghdr *, size_t);
1593int sock_no_recvmsg(struct kiocb *, struct socket *, struct msghdr *, size_t,
1594 int);
1595int sock_no_mmap(struct file *file, struct socket *sock,
1596 struct vm_area_struct *vma);
1597ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset,
1598 size_t size, int flags);
1599
1600/*
1601 * Functions to fill in entries in struct proto_ops when a protocol
1602 * uses the inet style.
1603 */
1604int sock_common_getsockopt(struct socket *sock, int level, int optname,
1605 char __user *optval, int __user *optlen);
1606int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock,
1607 struct msghdr *msg, size_t size, int flags);
1608int sock_common_setsockopt(struct socket *sock, int level, int optname,
1609 char __user *optval, unsigned int optlen);
1610int compat_sock_common_getsockopt(struct socket *sock, int level,
1611 int optname, char __user *optval, int __user *optlen);
1612int compat_sock_common_setsockopt(struct socket *sock, int level,
1613 int optname, char __user *optval, unsigned int optlen);
1614
1615void sk_common_release(struct sock *sk);
1616
1617/*
1618 * Default socket callbacks and setup code
1619 */
1620
1621/* Initialise core socket variables */
1622void sock_init_data(struct socket *sock, struct sock *sk);
1623
1624/*
1625 * Socket reference counting postulates.
1626 *
1627 * * Each user of socket SHOULD hold a reference count.
1628 * * Each access point to socket (an hash table bucket, reference from a list,
1629 * running timer, skb in flight MUST hold a reference count.
1630 * * When reference count hits 0, it means it will never increase back.
1631 * * When reference count hits 0, it means that no references from
1632 * outside exist to this socket and current process on current CPU
1633 * is last user and may/should destroy this socket.
1634 * * sk_free is called from any context: process, BH, IRQ. When
1635 * it is called, socket has no references from outside -> sk_free
1636 * may release descendant resources allocated by the socket, but
1637 * to the time when it is called, socket is NOT referenced by any
1638 * hash tables, lists etc.
1639 * * Packets, delivered from outside (from network or from another process)
1640 * and enqueued on receive/error queues SHOULD NOT grab reference count,
1641 * when they sit in queue. Otherwise, packets will leak to hole, when
1642 * socket is looked up by one cpu and unhasing is made by another CPU.
1643 * It is true for udp/raw, netlink (leak to receive and error queues), tcp
1644 * (leak to backlog). Packet socket does all the processing inside
1645 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
1646 * use separate SMP lock, so that they are prone too.
1647 */
1648
1649/* Ungrab socket and destroy it, if it was the last reference. */
1650static inline void sock_put(struct sock *sk)
1651{
1652 if (atomic_dec_and_test(&sk->sk_refcnt))
1653 sk_free(sk);
1654}
1655/* Generic version of sock_put(), dealing with all sockets
1656 * (TCP_TIMEWAIT, ESTABLISHED...)
1657 */
1658void sock_gen_put(struct sock *sk);
1659
1660int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested);
1661
1662static inline void sk_tx_queue_set(struct sock *sk, int tx_queue)
1663{
1664 sk->sk_tx_queue_mapping = tx_queue;
1665}
1666
1667static inline void sk_tx_queue_clear(struct sock *sk)
1668{
1669 sk->sk_tx_queue_mapping = -1;
1670}
1671
1672static inline int sk_tx_queue_get(const struct sock *sk)
1673{
1674 return sk ? sk->sk_tx_queue_mapping : -1;
1675}
1676
1677static inline void sk_set_socket(struct sock *sk, struct socket *sock)
1678{
1679 sk_tx_queue_clear(sk);
1680 sk->sk_socket = sock;
1681}
1682
1683static inline wait_queue_head_t *sk_sleep(struct sock *sk)
1684{
1685 BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0);
1686 return &rcu_dereference_raw(sk->sk_wq)->wait;
1687}
1688/* Detach socket from process context.
1689 * Announce socket dead, detach it from wait queue and inode.
1690 * Note that parent inode held reference count on this struct sock,
1691 * we do not release it in this function, because protocol
1692 * probably wants some additional cleanups or even continuing
1693 * to work with this socket (TCP).
1694 */
1695static inline void sock_orphan(struct sock *sk)
1696{
1697 write_lock_bh(&sk->sk_callback_lock);
1698 sock_set_flag(sk, SOCK_DEAD);
1699 sk_set_socket(sk, NULL);
1700 sk->sk_wq = NULL;
1701 write_unlock_bh(&sk->sk_callback_lock);
1702}
1703
1704static inline void sock_graft(struct sock *sk, struct socket *parent)
1705{
1706 write_lock_bh(&sk->sk_callback_lock);
1707 sk->sk_wq = parent->wq;
1708 parent->sk = sk;
1709 sk_set_socket(sk, parent);
1710 security_sock_graft(sk, parent);
1711 write_unlock_bh(&sk->sk_callback_lock);
1712}
1713
1714kuid_t sock_i_uid(struct sock *sk);
1715unsigned long sock_i_ino(struct sock *sk);
1716
1717static inline struct dst_entry *
1718__sk_dst_get(struct sock *sk)
1719{
1720 return rcu_dereference_check(sk->sk_dst_cache, sock_owned_by_user(sk) ||
1721 lockdep_is_held(&sk->sk_lock.slock));
1722}
1723
1724static inline struct dst_entry *
1725sk_dst_get(struct sock *sk)
1726{
1727 struct dst_entry *dst;
1728
1729 rcu_read_lock();
1730 dst = rcu_dereference(sk->sk_dst_cache);
1731 if (dst)
1732 dst_hold(dst);
1733 rcu_read_unlock();
1734 return dst;
1735}
1736
1737static inline void dst_negative_advice(struct sock *sk)
1738{
1739 struct dst_entry *ndst, *dst = __sk_dst_get(sk);
1740
1741 if (dst && dst->ops->negative_advice) {
1742 ndst = dst->ops->negative_advice(dst);
1743
1744 if (ndst != dst) {
1745 rcu_assign_pointer(sk->sk_dst_cache, ndst);
1746 sk_tx_queue_clear(sk);
1747 }
1748 }
1749}
1750
1751static inline void
1752__sk_dst_set(struct sock *sk, struct dst_entry *dst)
1753{
1754 struct dst_entry *old_dst;
1755
1756 sk_tx_queue_clear(sk);
1757 /*
1758 * This can be called while sk is owned by the caller only,
1759 * with no state that can be checked in a rcu_dereference_check() cond
1760 */
1761 old_dst = rcu_dereference_raw(sk->sk_dst_cache);
1762 rcu_assign_pointer(sk->sk_dst_cache, dst);
1763 dst_release(old_dst);
1764}
1765
1766static inline void
1767sk_dst_set(struct sock *sk, struct dst_entry *dst)
1768{
1769 spin_lock(&sk->sk_dst_lock);
1770 __sk_dst_set(sk, dst);
1771 spin_unlock(&sk->sk_dst_lock);
1772}
1773
1774static inline void
1775__sk_dst_reset(struct sock *sk)
1776{
1777 __sk_dst_set(sk, NULL);
1778}
1779
1780static inline void
1781sk_dst_reset(struct sock *sk)
1782{
1783 spin_lock(&sk->sk_dst_lock);
1784 __sk_dst_reset(sk);
1785 spin_unlock(&sk->sk_dst_lock);
1786}
1787
1788struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
1789
1790struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
1791
1792static inline bool sk_can_gso(const struct sock *sk)
1793{
1794 return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type);
1795}
1796
1797void sk_setup_caps(struct sock *sk, struct dst_entry *dst);
1798
1799static inline void sk_nocaps_add(struct sock *sk, netdev_features_t flags)
1800{
1801 sk->sk_route_nocaps |= flags;
1802 sk->sk_route_caps &= ~flags;
1803}
1804
1805static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
1806 char __user *from, char *to,
1807 int copy, int offset)
1808{
1809 if (skb->ip_summed == CHECKSUM_NONE) {
1810 int err = 0;
1811 __wsum csum = csum_and_copy_from_user(from, to, copy, 0, &err);
1812 if (err)
1813 return err;
1814 skb->csum = csum_block_add(skb->csum, csum, offset);
1815 } else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
1816 if (!access_ok(VERIFY_READ, from, copy) ||
1817 __copy_from_user_nocache(to, from, copy))
1818 return -EFAULT;
1819 } else if (copy_from_user(to, from, copy))
1820 return -EFAULT;
1821
1822 return 0;
1823}
1824
1825static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
1826 char __user *from, int copy)
1827{
1828 int err, offset = skb->len;
1829
1830 err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy),
1831 copy, offset);
1832 if (err)
1833 __skb_trim(skb, offset);
1834
1835 return err;
1836}
1837
1838static inline int skb_copy_to_page_nocache(struct sock *sk, char __user *from,
1839 struct sk_buff *skb,
1840 struct page *page,
1841 int off, int copy)
1842{
1843 int err;
1844
1845 err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off,
1846 copy, skb->len);
1847 if (err)
1848 return err;
1849
1850 skb->len += copy;
1851 skb->data_len += copy;
1852 skb->truesize += copy;
1853 sk->sk_wmem_queued += copy;
1854 sk_mem_charge(sk, copy);
1855 return 0;
1856}
1857
1858static inline int skb_copy_to_page(struct sock *sk, char __user *from,
1859 struct sk_buff *skb, struct page *page,
1860 int off, int copy)
1861{
1862 if (skb->ip_summed == CHECKSUM_NONE) {
1863 int err = 0;
1864 __wsum csum = csum_and_copy_from_user(from,
1865 page_address(page) + off,
1866 copy, 0, &err);
1867 if (err)
1868 return err;
1869 skb->csum = csum_block_add(skb->csum, csum, skb->len);
1870 } else if (copy_from_user(page_address(page) + off, from, copy))
1871 return -EFAULT;
1872
1873 skb->len += copy;
1874 skb->data_len += copy;
1875 skb->truesize += copy;
1876 sk->sk_wmem_queued += copy;
1877 sk_mem_charge(sk, copy);
1878 return 0;
1879}
1880
1881/**
1882 * sk_wmem_alloc_get - returns write allocations
1883 * @sk: socket
1884 *
1885 * Returns sk_wmem_alloc minus initial offset of one
1886 */
1887static inline int sk_wmem_alloc_get(const struct sock *sk)
1888{
1889 return atomic_read(&sk->sk_wmem_alloc) - 1;
1890}
1891
1892/**
1893 * sk_rmem_alloc_get - returns read allocations
1894 * @sk: socket
1895 *
1896 * Returns sk_rmem_alloc
1897 */
1898static inline int sk_rmem_alloc_get(const struct sock *sk)
1899{
1900 return atomic_read(&sk->sk_rmem_alloc);
1901}
1902
1903/**
1904 * sk_has_allocations - check if allocations are outstanding
1905 * @sk: socket
1906 *
1907 * Returns true if socket has write or read allocations
1908 */
1909static inline bool sk_has_allocations(const struct sock *sk)
1910{
1911 return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk);
1912}
1913
1914/**
1915 * wq_has_sleeper - check if there are any waiting processes
1916 * @wq: struct socket_wq
1917 *
1918 * Returns true if socket_wq has waiting processes
1919 *
1920 * The purpose of the wq_has_sleeper and sock_poll_wait is to wrap the memory
1921 * barrier call. They were added due to the race found within the tcp code.
1922 *
1923 * Consider following tcp code paths:
1924 *
1925 * CPU1 CPU2
1926 *
1927 * sys_select receive packet
1928 * ... ...
1929 * __add_wait_queue update tp->rcv_nxt
1930 * ... ...
1931 * tp->rcv_nxt check sock_def_readable
1932 * ... {
1933 * schedule rcu_read_lock();
1934 * wq = rcu_dereference(sk->sk_wq);
1935 * if (wq && waitqueue_active(&wq->wait))
1936 * wake_up_interruptible(&wq->wait)
1937 * ...
1938 * }
1939 *
1940 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
1941 * in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1
1942 * could then endup calling schedule and sleep forever if there are no more
1943 * data on the socket.
1944 *
1945 */
1946static inline bool wq_has_sleeper(struct socket_wq *wq)
1947{
1948 /* We need to be sure we are in sync with the
1949 * add_wait_queue modifications to the wait queue.
1950 *
1951 * This memory barrier is paired in the sock_poll_wait.
1952 */
1953 smp_mb();
1954 return wq && waitqueue_active(&wq->wait);
1955}
1956
1957/**
1958 * sock_poll_wait - place memory barrier behind the poll_wait call.
1959 * @filp: file
1960 * @wait_address: socket wait queue
1961 * @p: poll_table
1962 *
1963 * See the comments in the wq_has_sleeper function.
1964 */
1965static inline void sock_poll_wait(struct file *filp,
1966 wait_queue_head_t *wait_address, poll_table *p)
1967{
1968 if (!poll_does_not_wait(p) && wait_address) {
1969 poll_wait(filp, wait_address, p);
1970 /* We need to be sure we are in sync with the
1971 * socket flags modification.
1972 *
1973 * This memory barrier is paired in the wq_has_sleeper.
1974 */
1975 smp_mb();
1976 }
1977}
1978
1979/*
1980 * Queue a received datagram if it will fit. Stream and sequenced
1981 * protocols can't normally use this as they need to fit buffers in
1982 * and play with them.
1983 *
1984 * Inlined as it's very short and called for pretty much every
1985 * packet ever received.
1986 */
1987
1988static inline void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
1989{
1990 skb_orphan(skb);
1991 skb->sk = sk;
1992 skb->destructor = sock_wfree;
1993 /*
1994 * We used to take a refcount on sk, but following operation
1995 * is enough to guarantee sk_free() wont free this sock until
1996 * all in-flight packets are completed
1997 */
1998 atomic_add(skb->truesize, &sk->sk_wmem_alloc);
1999}
2000
2001static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
2002{
2003 skb_orphan(skb);
2004 skb->sk = sk;
2005 skb->destructor = sock_rfree;
2006 atomic_add(skb->truesize, &sk->sk_rmem_alloc);
2007 sk_mem_charge(sk, skb->truesize);
2008}
2009
2010void sk_reset_timer(struct sock *sk, struct timer_list *timer,
2011 unsigned long expires);
2012
2013void sk_stop_timer(struct sock *sk, struct timer_list *timer);
2014
2015int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
2016
2017int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
2018
2019/*
2020 * Recover an error report and clear atomically
2021 */
2022
2023static inline int sock_error(struct sock *sk)
2024{
2025 int err;
2026 if (likely(!sk->sk_err))
2027 return 0;
2028 err = xchg(&sk->sk_err, 0);
2029 return -err;
2030}
2031
2032static inline unsigned long sock_wspace(struct sock *sk)
2033{
2034 int amt = 0;
2035
2036 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
2037 amt = sk->sk_sndbuf - atomic_read(&sk->sk_wmem_alloc);
2038 if (amt < 0)
2039 amt = 0;
2040 }
2041 return amt;
2042}
2043
2044static inline void sk_wake_async(struct sock *sk, int how, int band)
2045{
2046 if (sock_flag(sk, SOCK_FASYNC))
2047 sock_wake_async(sk->sk_socket, how, band);
2048}
2049
2050/* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might
2051 * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak.
2052 * Note: for send buffers, TCP works better if we can build two skbs at
2053 * minimum.
2054 */
2055#define TCP_SKB_MIN_TRUESIZE (2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff)))
2056
2057#define SOCK_MIN_SNDBUF (TCP_SKB_MIN_TRUESIZE * 2)
2058#define SOCK_MIN_RCVBUF TCP_SKB_MIN_TRUESIZE
2059
2060static inline void sk_stream_moderate_sndbuf(struct sock *sk)
2061{
2062 if (!(sk->sk_userlocks & SOCK_SNDBUF_LOCK)) {
2063 sk->sk_sndbuf = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
2064 sk->sk_sndbuf = max_t(u32, sk->sk_sndbuf, SOCK_MIN_SNDBUF);
2065 }
2066}
2067
2068struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp);
2069
2070/**
2071 * sk_page_frag - return an appropriate page_frag
2072 * @sk: socket
2073 *
2074 * If socket allocation mode allows current thread to sleep, it means its
2075 * safe to use the per task page_frag instead of the per socket one.
2076 */
2077static inline struct page_frag *sk_page_frag(struct sock *sk)
2078{
2079 if (sk->sk_allocation & __GFP_WAIT)
2080 return ¤t->task_frag;
2081
2082 return &sk->sk_frag;
2083}
2084
2085bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag);
2086
2087/*
2088 * Default write policy as shown to user space via poll/select/SIGIO
2089 */
2090static inline bool sock_writeable(const struct sock *sk)
2091{
2092 return atomic_read(&sk->sk_wmem_alloc) < (sk->sk_sndbuf >> 1);
2093}
2094
2095static inline gfp_t gfp_any(void)
2096{
2097 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2098}
2099
2100static inline long sock_rcvtimeo(const struct sock *sk, bool noblock)
2101{
2102 return noblock ? 0 : sk->sk_rcvtimeo;
2103}
2104
2105static inline long sock_sndtimeo(const struct sock *sk, bool noblock)
2106{
2107 return noblock ? 0 : sk->sk_sndtimeo;
2108}
2109
2110static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
2111{
2112 return (waitall ? len : min_t(int, sk->sk_rcvlowat, len)) ? : 1;
2113}
2114
2115/* Alas, with timeout socket operations are not restartable.
2116 * Compare this to poll().
2117 */
2118static inline int sock_intr_errno(long timeo)
2119{
2120 return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
2121}
2122
2123void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
2124 struct sk_buff *skb);
2125void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
2126 struct sk_buff *skb);
2127
2128static inline void
2129sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
2130{
2131 ktime_t kt = skb->tstamp;
2132 struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
2133
2134 /*
2135 * generate control messages if
2136 * - receive time stamping in software requested (SOCK_RCVTSTAMP
2137 * or SOCK_TIMESTAMPING_RX_SOFTWARE)
2138 * - software time stamp available and wanted
2139 * (SOCK_TIMESTAMPING_SOFTWARE)
2140 * - hardware time stamps available and wanted
2141 * (SOCK_TIMESTAMPING_SYS_HARDWARE or
2142 * SOCK_TIMESTAMPING_RAW_HARDWARE)
2143 */
2144 if (sock_flag(sk, SOCK_RCVTSTAMP) ||
2145 sock_flag(sk, SOCK_TIMESTAMPING_RX_SOFTWARE) ||
2146 (kt.tv64 && sock_flag(sk, SOCK_TIMESTAMPING_SOFTWARE)) ||
2147 (hwtstamps->hwtstamp.tv64 &&
2148 sock_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE)) ||
2149 (hwtstamps->syststamp.tv64 &&
2150 sock_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE)))
2151 __sock_recv_timestamp(msg, sk, skb);
2152 else
2153 sk->sk_stamp = kt;
2154
2155 if (sock_flag(sk, SOCK_WIFI_STATUS) && skb->wifi_acked_valid)
2156 __sock_recv_wifi_status(msg, sk, skb);
2157}
2158
2159void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2160 struct sk_buff *skb);
2161
2162static inline void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2163 struct sk_buff *skb)
2164{
2165#define FLAGS_TS_OR_DROPS ((1UL << SOCK_RXQ_OVFL) | \
2166 (1UL << SOCK_RCVTSTAMP) | \
2167 (1UL << SOCK_TIMESTAMPING_SOFTWARE) | \
2168 (1UL << SOCK_TIMESTAMPING_RAW_HARDWARE) | \
2169 (1UL << SOCK_TIMESTAMPING_SYS_HARDWARE))
2170
2171 if (sk->sk_flags & FLAGS_TS_OR_DROPS)
2172 __sock_recv_ts_and_drops(msg, sk, skb);
2173 else
2174 sk->sk_stamp = skb->tstamp;
2175}
2176
2177/**
2178 * sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
2179 * @sk: socket sending this packet
2180 * @tx_flags: filled with instructions for time stamping
2181 *
2182 * Currently only depends on SOCK_TIMESTAMPING* flags.
2183 */
2184void sock_tx_timestamp(struct sock *sk, __u8 *tx_flags);
2185
2186/**
2187 * sk_eat_skb - Release a skb if it is no longer needed
2188 * @sk: socket to eat this skb from
2189 * @skb: socket buffer to eat
2190 * @copied_early: flag indicating whether DMA operations copied this data early
2191 *
2192 * This routine must be called with interrupts disabled or with the socket
2193 * locked so that the sk_buff queue operation is ok.
2194*/
2195#ifdef CONFIG_NET_DMA
2196static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb, bool copied_early)
2197{
2198 __skb_unlink(skb, &sk->sk_receive_queue);
2199 if (!copied_early)
2200 __kfree_skb(skb);
2201 else
2202 __skb_queue_tail(&sk->sk_async_wait_queue, skb);
2203}
2204#else
2205static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb, bool copied_early)
2206{
2207 __skb_unlink(skb, &sk->sk_receive_queue);
2208 __kfree_skb(skb);
2209}
2210#endif
2211
2212static inline
2213struct net *sock_net(const struct sock *sk)
2214{
2215 return read_pnet(&sk->sk_net);
2216}
2217
2218static inline
2219void sock_net_set(struct sock *sk, struct net *net)
2220{
2221 write_pnet(&sk->sk_net, net);
2222}
2223
2224/*
2225 * Kernel sockets, f.e. rtnl or icmp_socket, are a part of a namespace.
2226 * They should not hold a reference to a namespace in order to allow
2227 * to stop it.
2228 * Sockets after sk_change_net should be released using sk_release_kernel
2229 */
2230static inline void sk_change_net(struct sock *sk, struct net *net)
2231{
2232 struct net *current_net = sock_net(sk);
2233
2234 if (!net_eq(current_net, net)) {
2235 put_net(current_net);
2236 sock_net_set(sk, hold_net(net));
2237 }
2238}
2239
2240static inline struct sock *skb_steal_sock(struct sk_buff *skb)
2241{
2242 if (skb->sk) {
2243 struct sock *sk = skb->sk;
2244
2245 skb->destructor = NULL;
2246 skb->sk = NULL;
2247 return sk;
2248 }
2249 return NULL;
2250}
2251
2252void sock_enable_timestamp(struct sock *sk, int flag);
2253int sock_get_timestamp(struct sock *, struct timeval __user *);
2254int sock_get_timestampns(struct sock *, struct timespec __user *);
2255int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level,
2256 int type);
2257
2258bool sk_ns_capable(const struct sock *sk,
2259 struct user_namespace *user_ns, int cap);
2260bool sk_capable(const struct sock *sk, int cap);
2261bool sk_net_capable(const struct sock *sk, int cap);
2262
2263/*
2264 * Enable debug/info messages
2265 */
2266extern int net_msg_warn;
2267#define NETDEBUG(fmt, args...) \
2268 do { if (net_msg_warn) printk(fmt,##args); } while (0)
2269
2270#define LIMIT_NETDEBUG(fmt, args...) \
2271 do { if (net_msg_warn && net_ratelimit()) printk(fmt,##args); } while(0)
2272
2273extern __u32 sysctl_wmem_max;
2274extern __u32 sysctl_rmem_max;
2275
2276extern int sysctl_optmem_max;
2277
2278extern __u32 sysctl_wmem_default;
2279extern __u32 sysctl_rmem_default;
2280
2281#endif /* _SOCK_H */