Linux 3.12.39
[linux/fpc-iii.git] / include / net / sock.h
blob3899018a6b21a1619195692f6a494682acef3373
1 /*
2 * INET An implementation of the TCP/IP protocol suite for the LINUX
3 * operating system. INET is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
6 * Definitions for the AF_INET socket handler.
8 * Version: @(#)sock.h 1.0.4 05/13/93
10 * Authors: Ross Biro
11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12 * Corey Minyard <wf-rch!minyard@relay.EU.net>
13 * Florian La Roche <flla@stud.uni-sb.de>
15 * Fixes:
16 * Alan Cox : Volatiles in skbuff pointers. See
17 * skbuff comments. May be overdone,
18 * better to prove they can be removed
19 * than the reverse.
20 * Alan Cox : Added a zapped field for tcp to note
21 * a socket is reset and must stay shut up
22 * Alan Cox : New fields for options
23 * Pauline Middelink : identd support
24 * Alan Cox : Eliminate low level recv/recvfrom
25 * David S. Miller : New socket lookup architecture.
26 * Steve Whitehouse: Default routines for sock_ops
27 * Arnaldo C. Melo : removed net_pinfo, tp_pinfo and made
28 * protinfo be just a void pointer, as the
29 * protocol specific parts were moved to
30 * respective headers and ipv4/v6, etc now
31 * use private slabcaches for its socks
32 * Pedro Hortas : New flags field for socket options
35 * This program is free software; you can redistribute it and/or
36 * modify it under the terms of the GNU General Public License
37 * as published by the Free Software Foundation; either version
38 * 2 of the License, or (at your option) any later version.
40 #ifndef _SOCK_H
41 #define _SOCK_H
43 #include <linux/hardirq.h>
44 #include <linux/kernel.h>
45 #include <linux/list.h>
46 #include <linux/list_nulls.h>
47 #include <linux/timer.h>
48 #include <linux/cache.h>
49 #include <linux/bitops.h>
50 #include <linux/lockdep.h>
51 #include <linux/netdevice.h>
52 #include <linux/skbuff.h> /* struct sk_buff */
53 #include <linux/mm.h>
54 #include <linux/security.h>
55 #include <linux/slab.h>
56 #include <linux/uaccess.h>
57 #include <linux/memcontrol.h>
58 #include <linux/res_counter.h>
59 #include <linux/static_key.h>
60 #include <linux/aio.h>
61 #include <linux/sched.h>
63 #include <linux/filter.h>
64 #include <linux/rculist_nulls.h>
65 #include <linux/poll.h>
67 #include <linux/atomic.h>
68 #include <net/dst.h>
69 #include <net/checksum.h>
71 struct cgroup;
72 struct cgroup_subsys;
73 #ifdef CONFIG_NET
74 int mem_cgroup_sockets_init(struct mem_cgroup *memcg, struct cgroup_subsys *ss);
75 void mem_cgroup_sockets_destroy(struct mem_cgroup *memcg);
76 #else
77 static inline
78 int mem_cgroup_sockets_init(struct mem_cgroup *memcg, struct cgroup_subsys *ss)
80 return 0;
82 static inline
83 void mem_cgroup_sockets_destroy(struct mem_cgroup *memcg)
86 #endif
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.
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 */
100 static inline __printf(2, 3)
101 void SOCK_DEBUG(const struct sock *sk, const char *msg, ...)
104 #endif
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.
110 typedef struct {
111 spinlock_t slock;
112 int owned;
113 wait_queue_head_t wq;
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):
120 #ifdef CONFIG_DEBUG_LOCK_ALLOC
121 struct lockdep_map dep_map;
122 #endif
123 } socket_lock_t;
125 struct sock;
126 struct proto;
127 struct net;
129 typedef __u32 __bitwise __portpair;
130 typedef __u64 __bitwise __addrpair;
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
154 * This is the minimal network layer representation of sockets, the header
155 * for struct sock and struct inet_timewait_sock.
157 struct 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() and INET_TW_MATCH()
161 union {
162 __addrpair skc_addrpair;
163 struct {
164 __be32 skc_daddr;
165 __be32 skc_rcv_saddr;
168 union {
169 unsigned int skc_hash;
170 __u16 skc_u16hashes[2];
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;
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;
190 struct proto *skc_prot;
191 #ifdef CONFIG_NET_NS
192 struct net *skc_net;
193 #endif
195 * fields between dontcopy_begin/dontcopy_end
196 * are not copied in sock_copy()
198 /* private: */
199 int skc_dontcopy_begin[0];
200 /* public: */
201 union {
202 struct hlist_node skc_node;
203 struct hlist_nulls_node skc_nulls_node;
205 int skc_tx_queue_mapping;
206 atomic_t skc_refcnt;
207 /* private: */
208 int skc_dontcopy_end[0];
209 /* public: */
212 struct cg_proto;
214 * struct sock - network layer representation of sockets
215 * @__sk_common: shared layout with inet_timewait_sock
216 * @sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
217 * @sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
218 * @sk_lock: synchronizer
219 * @sk_rcvbuf: size of receive buffer in bytes
220 * @sk_wq: sock wait queue and async head
221 * @sk_rx_dst: receive input route used by early tcp demux
222 * @sk_dst_cache: destination cache
223 * @sk_dst_lock: destination cache lock
224 * @sk_policy: flow policy
225 * @sk_receive_queue: incoming packets
226 * @sk_wmem_alloc: transmit queue bytes committed
227 * @sk_write_queue: Packet sending queue
228 * @sk_async_wait_queue: DMA copied packets
229 * @sk_omem_alloc: "o" is "option" or "other"
230 * @sk_wmem_queued: persistent queue size
231 * @sk_forward_alloc: space allocated forward
232 * @sk_napi_id: id of the last napi context to receive data for sk
233 * @sk_ll_usec: usecs to busypoll when there is no data
234 * @sk_allocation: allocation mode
235 * @sk_pacing_rate: Pacing rate (if supported by transport/packet scheduler)
236 * @sk_sndbuf: size of send buffer in bytes
237 * @sk_flags: %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE,
238 * %SO_OOBINLINE settings, %SO_TIMESTAMPING settings
239 * @sk_no_check: %SO_NO_CHECK setting, whether or not checkup packets
240 * @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
241 * @sk_route_nocaps: forbidden route capabilities (e.g NETIF_F_GSO_MASK)
242 * @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
243 * @sk_gso_max_size: Maximum GSO segment size to build
244 * @sk_gso_max_segs: Maximum number of GSO segments
245 * @sk_lingertime: %SO_LINGER l_linger setting
246 * @sk_backlog: always used with the per-socket spinlock held
247 * @sk_callback_lock: used with the callbacks in the end of this struct
248 * @sk_error_queue: rarely used
249 * @sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt,
250 * IPV6_ADDRFORM for instance)
251 * @sk_err: last error
252 * @sk_err_soft: errors that don't cause failure but are the cause of a
253 * persistent failure not just 'timed out'
254 * @sk_drops: raw/udp drops counter
255 * @sk_ack_backlog: current listen backlog
256 * @sk_max_ack_backlog: listen backlog set in listen()
257 * @sk_priority: %SO_PRIORITY setting
258 * @sk_cgrp_prioidx: socket group's priority map index
259 * @sk_type: socket type (%SOCK_STREAM, etc)
260 * @sk_protocol: which protocol this socket belongs in this network family
261 * @sk_peer_pid: &struct pid for this socket's peer
262 * @sk_peer_cred: %SO_PEERCRED setting
263 * @sk_rcvlowat: %SO_RCVLOWAT setting
264 * @sk_rcvtimeo: %SO_RCVTIMEO setting
265 * @sk_sndtimeo: %SO_SNDTIMEO setting
266 * @sk_rxhash: flow hash received from netif layer
267 * @sk_filter: socket filtering instructions
268 * @sk_protinfo: private area, net family specific, when not using slab
269 * @sk_timer: sock cleanup timer
270 * @sk_stamp: time stamp of last packet received
271 * @sk_socket: Identd and reporting IO signals
272 * @sk_user_data: RPC layer private data
273 * @sk_frag: cached page frag
274 * @sk_peek_off: current peek_offset value
275 * @sk_send_head: front of stuff to transmit
276 * @sk_security: used by security modules
277 * @sk_mark: generic packet mark
278 * @sk_classid: this socket's cgroup classid
279 * @sk_cgrp: this socket's cgroup-specific proto data
280 * @sk_write_pending: a write to stream socket waits to start
281 * @sk_state_change: callback to indicate change in the state of the sock
282 * @sk_data_ready: callback to indicate there is data to be processed
283 * @sk_write_space: callback to indicate there is bf sending space available
284 * @sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
285 * @sk_backlog_rcv: callback to process the backlog
286 * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
288 struct sock {
290 * Now struct inet_timewait_sock also uses sock_common, so please just
291 * don't add nothing before this first member (__sk_common) --acme
293 struct sock_common __sk_common;
294 #define sk_node __sk_common.skc_node
295 #define sk_nulls_node __sk_common.skc_nulls_node
296 #define sk_refcnt __sk_common.skc_refcnt
297 #define sk_tx_queue_mapping __sk_common.skc_tx_queue_mapping
299 #define sk_dontcopy_begin __sk_common.skc_dontcopy_begin
300 #define sk_dontcopy_end __sk_common.skc_dontcopy_end
301 #define sk_hash __sk_common.skc_hash
302 #define sk_family __sk_common.skc_family
303 #define sk_state __sk_common.skc_state
304 #define sk_reuse __sk_common.skc_reuse
305 #define sk_reuseport __sk_common.skc_reuseport
306 #define sk_bound_dev_if __sk_common.skc_bound_dev_if
307 #define sk_bind_node __sk_common.skc_bind_node
308 #define sk_prot __sk_common.skc_prot
309 #define sk_net __sk_common.skc_net
310 socket_lock_t sk_lock;
311 struct sk_buff_head sk_receive_queue;
313 * The backlog queue is special, it is always used with
314 * the per-socket spinlock held and requires low latency
315 * access. Therefore we special case it's implementation.
316 * Note : rmem_alloc is in this structure to fill a hole
317 * on 64bit arches, not because its logically part of
318 * backlog.
320 struct {
321 atomic_t rmem_alloc;
322 int len;
323 struct sk_buff *head;
324 struct sk_buff *tail;
325 } sk_backlog;
326 #define sk_rmem_alloc sk_backlog.rmem_alloc
327 int sk_forward_alloc;
328 #ifdef CONFIG_RPS
329 __u32 sk_rxhash;
330 #endif
331 #ifdef CONFIG_NET_RX_BUSY_POLL
332 unsigned int sk_napi_id;
333 unsigned int sk_ll_usec;
334 #endif
335 atomic_t sk_drops;
336 int sk_rcvbuf;
338 struct sk_filter __rcu *sk_filter;
339 struct socket_wq __rcu *sk_wq;
341 #ifdef CONFIG_NET_DMA
342 struct sk_buff_head sk_async_wait_queue;
343 #endif
345 #ifdef CONFIG_XFRM
346 struct xfrm_policy *sk_policy[2];
347 #endif
348 unsigned long sk_flags;
349 struct dst_entry *sk_rx_dst;
350 struct dst_entry __rcu *sk_dst_cache;
351 spinlock_t sk_dst_lock;
352 atomic_t sk_wmem_alloc;
353 atomic_t sk_omem_alloc;
354 int sk_sndbuf;
355 struct sk_buff_head sk_write_queue;
356 kmemcheck_bitfield_begin(flags);
357 unsigned int sk_shutdown : 2,
358 sk_no_check : 2,
359 sk_userlocks : 4,
360 sk_protocol : 8,
361 sk_type : 16;
362 kmemcheck_bitfield_end(flags);
363 int sk_wmem_queued;
364 gfp_t sk_allocation;
365 u32 sk_pacing_rate; /* bytes per second */
366 netdev_features_t sk_route_caps;
367 netdev_features_t sk_route_nocaps;
368 int sk_gso_type;
369 unsigned int sk_gso_max_size;
370 u16 sk_gso_max_segs;
371 int sk_rcvlowat;
372 unsigned long sk_lingertime;
373 struct sk_buff_head sk_error_queue;
374 struct proto *sk_prot_creator;
375 rwlock_t sk_callback_lock;
376 int sk_err,
377 sk_err_soft;
378 unsigned short sk_ack_backlog;
379 unsigned short sk_max_ack_backlog;
380 __u32 sk_priority;
381 #if IS_ENABLED(CONFIG_NETPRIO_CGROUP)
382 __u32 sk_cgrp_prioidx;
383 #endif
384 struct pid *sk_peer_pid;
385 const struct cred *sk_peer_cred;
386 long sk_rcvtimeo;
387 long sk_sndtimeo;
388 void *sk_protinfo;
389 struct timer_list sk_timer;
390 ktime_t sk_stamp;
391 struct socket *sk_socket;
392 void *sk_user_data;
393 struct page_frag sk_frag;
394 struct sk_buff *sk_send_head;
395 __s32 sk_peek_off;
396 int sk_write_pending;
397 #ifdef CONFIG_SECURITY
398 void *sk_security;
399 #endif
400 __u32 sk_mark;
401 u32 sk_classid;
402 struct cg_proto *sk_cgrp;
403 void (*sk_state_change)(struct sock *sk);
404 void (*sk_data_ready)(struct sock *sk, int bytes);
405 void (*sk_write_space)(struct sock *sk);
406 void (*sk_error_report)(struct sock *sk);
407 int (*sk_backlog_rcv)(struct sock *sk,
408 struct sk_buff *skb);
409 void (*sk_destruct)(struct sock *sk);
412 #define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data)))
414 #define rcu_dereference_sk_user_data(sk) rcu_dereference(__sk_user_data((sk)))
415 #define rcu_assign_sk_user_data(sk, ptr) rcu_assign_pointer(__sk_user_data((sk)), ptr)
418 * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK
419 * or not whether his port will be reused by someone else. SK_FORCE_REUSE
420 * on a socket means that the socket will reuse everybody else's port
421 * without looking at the other's sk_reuse value.
424 #define SK_NO_REUSE 0
425 #define SK_CAN_REUSE 1
426 #define SK_FORCE_REUSE 2
428 static inline int sk_peek_offset(struct sock *sk, int flags)
430 if ((flags & MSG_PEEK) && (sk->sk_peek_off >= 0))
431 return sk->sk_peek_off;
432 else
433 return 0;
436 static inline void sk_peek_offset_bwd(struct sock *sk, int val)
438 if (sk->sk_peek_off >= 0) {
439 if (sk->sk_peek_off >= val)
440 sk->sk_peek_off -= val;
441 else
442 sk->sk_peek_off = 0;
446 static inline void sk_peek_offset_fwd(struct sock *sk, int val)
448 if (sk->sk_peek_off >= 0)
449 sk->sk_peek_off += val;
453 * Hashed lists helper routines
455 static inline struct sock *sk_entry(const struct hlist_node *node)
457 return hlist_entry(node, struct sock, sk_node);
460 static inline struct sock *__sk_head(const struct hlist_head *head)
462 return hlist_entry(head->first, struct sock, sk_node);
465 static inline struct sock *sk_head(const struct hlist_head *head)
467 return hlist_empty(head) ? NULL : __sk_head(head);
470 static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head)
472 return hlist_nulls_entry(head->first, struct sock, sk_nulls_node);
475 static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head)
477 return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head);
480 static inline struct sock *sk_next(const struct sock *sk)
482 return sk->sk_node.next ?
483 hlist_entry(sk->sk_node.next, struct sock, sk_node) : NULL;
486 static inline struct sock *sk_nulls_next(const struct sock *sk)
488 return (!is_a_nulls(sk->sk_nulls_node.next)) ?
489 hlist_nulls_entry(sk->sk_nulls_node.next,
490 struct sock, sk_nulls_node) :
491 NULL;
494 static inline bool sk_unhashed(const struct sock *sk)
496 return hlist_unhashed(&sk->sk_node);
499 static inline bool sk_hashed(const struct sock *sk)
501 return !sk_unhashed(sk);
504 static inline void sk_node_init(struct hlist_node *node)
506 node->pprev = NULL;
509 static inline void sk_nulls_node_init(struct hlist_nulls_node *node)
511 node->pprev = NULL;
514 static inline void __sk_del_node(struct sock *sk)
516 __hlist_del(&sk->sk_node);
519 /* NB: equivalent to hlist_del_init_rcu */
520 static inline bool __sk_del_node_init(struct sock *sk)
522 if (sk_hashed(sk)) {
523 __sk_del_node(sk);
524 sk_node_init(&sk->sk_node);
525 return true;
527 return false;
530 /* Grab socket reference count. This operation is valid only
531 when sk is ALREADY grabbed f.e. it is found in hash table
532 or a list and the lookup is made under lock preventing hash table
533 modifications.
536 static inline void sock_hold(struct sock *sk)
538 atomic_inc(&sk->sk_refcnt);
541 /* Ungrab socket in the context, which assumes that socket refcnt
542 cannot hit zero, f.e. it is true in context of any socketcall.
544 static inline void __sock_put(struct sock *sk)
546 atomic_dec(&sk->sk_refcnt);
549 static inline bool sk_del_node_init(struct sock *sk)
551 bool rc = __sk_del_node_init(sk);
553 if (rc) {
554 /* paranoid for a while -acme */
555 WARN_ON(atomic_read(&sk->sk_refcnt) == 1);
556 __sock_put(sk);
558 return rc;
560 #define sk_del_node_init_rcu(sk) sk_del_node_init(sk)
562 static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk)
564 if (sk_hashed(sk)) {
565 hlist_nulls_del_init_rcu(&sk->sk_nulls_node);
566 return true;
568 return false;
571 static inline bool sk_nulls_del_node_init_rcu(struct sock *sk)
573 bool rc = __sk_nulls_del_node_init_rcu(sk);
575 if (rc) {
576 /* paranoid for a while -acme */
577 WARN_ON(atomic_read(&sk->sk_refcnt) == 1);
578 __sock_put(sk);
580 return rc;
583 static inline void __sk_add_node(struct sock *sk, struct hlist_head *list)
585 hlist_add_head(&sk->sk_node, list);
588 static inline void sk_add_node(struct sock *sk, struct hlist_head *list)
590 sock_hold(sk);
591 __sk_add_node(sk, list);
594 static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list)
596 sock_hold(sk);
597 hlist_add_head_rcu(&sk->sk_node, list);
600 static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
602 hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list);
605 static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
607 sock_hold(sk);
608 __sk_nulls_add_node_rcu(sk, list);
611 static inline void __sk_del_bind_node(struct sock *sk)
613 __hlist_del(&sk->sk_bind_node);
616 static inline void sk_add_bind_node(struct sock *sk,
617 struct hlist_head *list)
619 hlist_add_head(&sk->sk_bind_node, list);
622 #define sk_for_each(__sk, list) \
623 hlist_for_each_entry(__sk, list, sk_node)
624 #define sk_for_each_rcu(__sk, list) \
625 hlist_for_each_entry_rcu(__sk, list, sk_node)
626 #define sk_nulls_for_each(__sk, node, list) \
627 hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)
628 #define sk_nulls_for_each_rcu(__sk, node, list) \
629 hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)
630 #define sk_for_each_from(__sk) \
631 hlist_for_each_entry_from(__sk, sk_node)
632 #define sk_nulls_for_each_from(__sk, node) \
633 if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \
634 hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node)
635 #define sk_for_each_safe(__sk, tmp, list) \
636 hlist_for_each_entry_safe(__sk, tmp, list, sk_node)
637 #define sk_for_each_bound(__sk, list) \
638 hlist_for_each_entry(__sk, list, sk_bind_node)
640 static inline struct user_namespace *sk_user_ns(struct sock *sk)
642 /* Careful only use this in a context where these parameters
643 * can not change and must all be valid, such as recvmsg from
644 * userspace.
646 return sk->sk_socket->file->f_cred->user_ns;
649 /* Sock flags */
650 enum sock_flags {
651 SOCK_DEAD,
652 SOCK_DONE,
653 SOCK_URGINLINE,
654 SOCK_KEEPOPEN,
655 SOCK_LINGER,
656 SOCK_DESTROY,
657 SOCK_BROADCAST,
658 SOCK_TIMESTAMP,
659 SOCK_ZAPPED,
660 SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */
661 SOCK_DBG, /* %SO_DEBUG setting */
662 SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
663 SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */
664 SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
665 SOCK_QUEUE_SHRUNK, /* write queue has been shrunk recently */
666 SOCK_MEMALLOC, /* VM depends on this socket for swapping */
667 SOCK_TIMESTAMPING_TX_HARDWARE, /* %SOF_TIMESTAMPING_TX_HARDWARE */
668 SOCK_TIMESTAMPING_TX_SOFTWARE, /* %SOF_TIMESTAMPING_TX_SOFTWARE */
669 SOCK_TIMESTAMPING_RX_HARDWARE, /* %SOF_TIMESTAMPING_RX_HARDWARE */
670 SOCK_TIMESTAMPING_RX_SOFTWARE, /* %SOF_TIMESTAMPING_RX_SOFTWARE */
671 SOCK_TIMESTAMPING_SOFTWARE, /* %SOF_TIMESTAMPING_SOFTWARE */
672 SOCK_TIMESTAMPING_RAW_HARDWARE, /* %SOF_TIMESTAMPING_RAW_HARDWARE */
673 SOCK_TIMESTAMPING_SYS_HARDWARE, /* %SOF_TIMESTAMPING_SYS_HARDWARE */
674 SOCK_FASYNC, /* fasync() active */
675 SOCK_RXQ_OVFL,
676 SOCK_ZEROCOPY, /* buffers from userspace */
677 SOCK_WIFI_STATUS, /* push wifi status to userspace */
678 SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS.
679 * Will use last 4 bytes of packet sent from
680 * user-space instead.
682 SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */
683 SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */
686 static inline void sock_copy_flags(struct sock *nsk, struct sock *osk)
688 nsk->sk_flags = osk->sk_flags;
691 static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
693 __set_bit(flag, &sk->sk_flags);
696 static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag)
698 __clear_bit(flag, &sk->sk_flags);
701 static inline bool sock_flag(const struct sock *sk, enum sock_flags flag)
703 return test_bit(flag, &sk->sk_flags);
706 #ifdef CONFIG_NET
707 extern struct static_key memalloc_socks;
708 static inline int sk_memalloc_socks(void)
710 return static_key_false(&memalloc_socks);
712 #else
714 static inline int sk_memalloc_socks(void)
716 return 0;
719 #endif
721 static inline gfp_t sk_gfp_atomic(struct sock *sk, gfp_t gfp_mask)
723 return GFP_ATOMIC | (sk->sk_allocation & __GFP_MEMALLOC);
726 static inline void sk_acceptq_removed(struct sock *sk)
728 sk->sk_ack_backlog--;
731 static inline void sk_acceptq_added(struct sock *sk)
733 sk->sk_ack_backlog++;
736 static inline bool sk_acceptq_is_full(const struct sock *sk)
738 return sk->sk_ack_backlog > sk->sk_max_ack_backlog;
742 * Compute minimal free write space needed to queue new packets.
744 static inline int sk_stream_min_wspace(const struct sock *sk)
746 return sk->sk_wmem_queued >> 1;
749 static inline int sk_stream_wspace(const struct sock *sk)
751 return sk->sk_sndbuf - sk->sk_wmem_queued;
754 extern void sk_stream_write_space(struct sock *sk);
756 /* OOB backlog add */
757 static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
759 /* dont let skb dst not refcounted, we are going to leave rcu lock */
760 skb_dst_force(skb);
762 if (!sk->sk_backlog.tail)
763 sk->sk_backlog.head = skb;
764 else
765 sk->sk_backlog.tail->next = skb;
767 sk->sk_backlog.tail = skb;
768 skb->next = NULL;
772 * Take into account size of receive queue and backlog queue
773 * Do not take into account this skb truesize,
774 * to allow even a single big packet to come.
776 static inline bool sk_rcvqueues_full(const struct sock *sk, const struct sk_buff *skb,
777 unsigned int limit)
779 unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc);
781 return qsize > limit;
784 /* The per-socket spinlock must be held here. */
785 static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb,
786 unsigned int limit)
788 if (sk_rcvqueues_full(sk, skb, limit))
789 return -ENOBUFS;
791 __sk_add_backlog(sk, skb);
792 sk->sk_backlog.len += skb->truesize;
793 return 0;
796 extern int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb);
798 static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
800 if (sk_memalloc_socks() && skb_pfmemalloc(skb))
801 return __sk_backlog_rcv(sk, skb);
803 return sk->sk_backlog_rcv(sk, skb);
806 static inline void sock_rps_record_flow(const struct sock *sk)
808 #ifdef CONFIG_RPS
809 struct rps_sock_flow_table *sock_flow_table;
811 rcu_read_lock();
812 sock_flow_table = rcu_dereference(rps_sock_flow_table);
813 rps_record_sock_flow(sock_flow_table, sk->sk_rxhash);
814 rcu_read_unlock();
815 #endif
818 static inline void sock_rps_reset_flow(const struct sock *sk)
820 #ifdef CONFIG_RPS
821 struct rps_sock_flow_table *sock_flow_table;
823 rcu_read_lock();
824 sock_flow_table = rcu_dereference(rps_sock_flow_table);
825 rps_reset_sock_flow(sock_flow_table, sk->sk_rxhash);
826 rcu_read_unlock();
827 #endif
830 static inline void sock_rps_save_rxhash(struct sock *sk,
831 const struct sk_buff *skb)
833 #ifdef CONFIG_RPS
834 if (unlikely(sk->sk_rxhash != skb->rxhash)) {
835 sock_rps_reset_flow(sk);
836 sk->sk_rxhash = skb->rxhash;
838 #endif
841 static inline void sock_rps_reset_rxhash(struct sock *sk)
843 #ifdef CONFIG_RPS
844 sock_rps_reset_flow(sk);
845 sk->sk_rxhash = 0;
846 #endif
849 #define sk_wait_event(__sk, __timeo, __condition) \
850 ({ int __rc; \
851 release_sock(__sk); \
852 __rc = __condition; \
853 if (!__rc) { \
854 *(__timeo) = schedule_timeout(*(__timeo)); \
856 lock_sock(__sk); \
857 __rc = __condition; \
858 __rc; \
861 extern int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
862 extern int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
863 extern void sk_stream_wait_close(struct sock *sk, long timeo_p);
864 extern int sk_stream_error(struct sock *sk, int flags, int err);
865 extern void sk_stream_kill_queues(struct sock *sk);
866 extern void sk_set_memalloc(struct sock *sk);
867 extern void sk_clear_memalloc(struct sock *sk);
869 extern int sk_wait_data(struct sock *sk, long *timeo);
871 struct request_sock_ops;
872 struct timewait_sock_ops;
873 struct inet_hashinfo;
874 struct raw_hashinfo;
875 struct module;
878 * caches using SLAB_DESTROY_BY_RCU should let .next pointer from nulls nodes
879 * un-modified. Special care is taken when initializing object to zero.
881 static inline void sk_prot_clear_nulls(struct sock *sk, int size)
883 if (offsetof(struct sock, sk_node.next) != 0)
884 memset(sk, 0, offsetof(struct sock, sk_node.next));
885 memset(&sk->sk_node.pprev, 0,
886 size - offsetof(struct sock, sk_node.pprev));
889 /* Networking protocol blocks we attach to sockets.
890 * socket layer -> transport layer interface
891 * transport -> network interface is defined by struct inet_proto
893 struct proto {
894 void (*close)(struct sock *sk,
895 long timeout);
896 int (*connect)(struct sock *sk,
897 struct sockaddr *uaddr,
898 int addr_len);
899 int (*disconnect)(struct sock *sk, int flags);
901 struct sock * (*accept)(struct sock *sk, int flags, int *err);
903 int (*ioctl)(struct sock *sk, int cmd,
904 unsigned long arg);
905 int (*init)(struct sock *sk);
906 void (*destroy)(struct sock *sk);
907 void (*shutdown)(struct sock *sk, int how);
908 int (*setsockopt)(struct sock *sk, int level,
909 int optname, char __user *optval,
910 unsigned int optlen);
911 int (*getsockopt)(struct sock *sk, int level,
912 int optname, char __user *optval,
913 int __user *option);
914 #ifdef CONFIG_COMPAT
915 int (*compat_setsockopt)(struct sock *sk,
916 int level,
917 int optname, char __user *optval,
918 unsigned int optlen);
919 int (*compat_getsockopt)(struct sock *sk,
920 int level,
921 int optname, char __user *optval,
922 int __user *option);
923 int (*compat_ioctl)(struct sock *sk,
924 unsigned int cmd, unsigned long arg);
925 #endif
926 int (*sendmsg)(struct kiocb *iocb, struct sock *sk,
927 struct msghdr *msg, size_t len);
928 int (*recvmsg)(struct kiocb *iocb, struct sock *sk,
929 struct msghdr *msg,
930 size_t len, int noblock, int flags,
931 int *addr_len);
932 int (*sendpage)(struct sock *sk, struct page *page,
933 int offset, size_t size, int flags);
934 int (*bind)(struct sock *sk,
935 struct sockaddr *uaddr, int addr_len);
937 int (*backlog_rcv) (struct sock *sk,
938 struct sk_buff *skb);
940 void (*release_cb)(struct sock *sk);
942 /* Keeping track of sk's, looking them up, and port selection methods. */
943 void (*hash)(struct sock *sk);
944 void (*unhash)(struct sock *sk);
945 void (*rehash)(struct sock *sk);
946 int (*get_port)(struct sock *sk, unsigned short snum);
947 void (*clear_sk)(struct sock *sk, int size);
949 /* Keeping track of sockets in use */
950 #ifdef CONFIG_PROC_FS
951 unsigned int inuse_idx;
952 #endif
954 bool (*stream_memory_free)(const struct sock *sk);
955 /* Memory pressure */
956 void (*enter_memory_pressure)(struct sock *sk);
957 atomic_long_t *memory_allocated; /* Current allocated memory. */
958 struct percpu_counter *sockets_allocated; /* Current number of sockets. */
960 * Pressure flag: try to collapse.
961 * Technical note: it is used by multiple contexts non atomically.
962 * All the __sk_mem_schedule() is of this nature: accounting
963 * is strict, actions are advisory and have some latency.
965 int *memory_pressure;
966 long *sysctl_mem;
967 int *sysctl_wmem;
968 int *sysctl_rmem;
969 int max_header;
970 bool no_autobind;
972 struct kmem_cache *slab;
973 unsigned int obj_size;
974 int slab_flags;
976 struct percpu_counter *orphan_count;
978 struct request_sock_ops *rsk_prot;
979 struct timewait_sock_ops *twsk_prot;
981 union {
982 struct inet_hashinfo *hashinfo;
983 struct udp_table *udp_table;
984 struct raw_hashinfo *raw_hash;
985 } h;
987 struct module *owner;
989 char name[32];
991 struct list_head node;
992 #ifdef SOCK_REFCNT_DEBUG
993 atomic_t socks;
994 #endif
995 #ifdef CONFIG_MEMCG_KMEM
997 * cgroup specific init/deinit functions. Called once for all
998 * protocols that implement it, from cgroups populate function.
999 * This function has to setup any files the protocol want to
1000 * appear in the kmem cgroup filesystem.
1002 int (*init_cgroup)(struct mem_cgroup *memcg,
1003 struct cgroup_subsys *ss);
1004 void (*destroy_cgroup)(struct mem_cgroup *memcg);
1005 struct cg_proto *(*proto_cgroup)(struct mem_cgroup *memcg);
1006 #endif
1010 * Bits in struct cg_proto.flags
1012 enum cg_proto_flags {
1013 /* Currently active and new sockets should be assigned to cgroups */
1014 MEMCG_SOCK_ACTIVE,
1015 /* It was ever activated; we must disarm static keys on destruction */
1016 MEMCG_SOCK_ACTIVATED,
1019 struct cg_proto {
1020 void (*enter_memory_pressure)(struct sock *sk);
1021 struct res_counter *memory_allocated; /* Current allocated memory. */
1022 struct percpu_counter *sockets_allocated; /* Current number of sockets. */
1023 int *memory_pressure;
1024 long *sysctl_mem;
1025 unsigned long flags;
1027 * memcg field is used to find which memcg we belong directly
1028 * Each memcg struct can hold more than one cg_proto, so container_of
1029 * won't really cut.
1031 * The elegant solution would be having an inverse function to
1032 * proto_cgroup in struct proto, but that means polluting the structure
1033 * for everybody, instead of just for memcg users.
1035 struct mem_cgroup *memcg;
1038 extern int proto_register(struct proto *prot, int alloc_slab);
1039 extern void proto_unregister(struct proto *prot);
1041 static inline bool memcg_proto_active(struct cg_proto *cg_proto)
1043 return test_bit(MEMCG_SOCK_ACTIVE, &cg_proto->flags);
1046 static inline bool memcg_proto_activated(struct cg_proto *cg_proto)
1048 return test_bit(MEMCG_SOCK_ACTIVATED, &cg_proto->flags);
1051 #ifdef SOCK_REFCNT_DEBUG
1052 static inline void sk_refcnt_debug_inc(struct sock *sk)
1054 atomic_inc(&sk->sk_prot->socks);
1057 static inline void sk_refcnt_debug_dec(struct sock *sk)
1059 atomic_dec(&sk->sk_prot->socks);
1060 printk(KERN_DEBUG "%s socket %p released, %d are still alive\n",
1061 sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks));
1064 static inline void sk_refcnt_debug_release(const struct sock *sk)
1066 if (atomic_read(&sk->sk_refcnt) != 1)
1067 printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n",
1068 sk->sk_prot->name, sk, atomic_read(&sk->sk_refcnt));
1070 #else /* SOCK_REFCNT_DEBUG */
1071 #define sk_refcnt_debug_inc(sk) do { } while (0)
1072 #define sk_refcnt_debug_dec(sk) do { } while (0)
1073 #define sk_refcnt_debug_release(sk) do { } while (0)
1074 #endif /* SOCK_REFCNT_DEBUG */
1076 #if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_NET)
1077 extern struct static_key memcg_socket_limit_enabled;
1078 static inline struct cg_proto *parent_cg_proto(struct proto *proto,
1079 struct cg_proto *cg_proto)
1081 return proto->proto_cgroup(parent_mem_cgroup(cg_proto->memcg));
1083 #define mem_cgroup_sockets_enabled static_key_false(&memcg_socket_limit_enabled)
1084 #else
1085 #define mem_cgroup_sockets_enabled 0
1086 static inline struct cg_proto *parent_cg_proto(struct proto *proto,
1087 struct cg_proto *cg_proto)
1089 return NULL;
1091 #endif
1093 static inline bool sk_stream_memory_free(const struct sock *sk)
1095 if (sk->sk_wmem_queued >= sk->sk_sndbuf)
1096 return false;
1098 return sk->sk_prot->stream_memory_free ?
1099 sk->sk_prot->stream_memory_free(sk) : true;
1102 static inline bool sk_stream_is_writeable(const struct sock *sk)
1104 return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) &&
1105 sk_stream_memory_free(sk);
1109 static inline bool sk_has_memory_pressure(const struct sock *sk)
1111 return sk->sk_prot->memory_pressure != NULL;
1114 static inline bool sk_under_memory_pressure(const struct sock *sk)
1116 if (!sk->sk_prot->memory_pressure)
1117 return false;
1119 if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1120 return !!*sk->sk_cgrp->memory_pressure;
1122 return !!*sk->sk_prot->memory_pressure;
1125 static inline void sk_leave_memory_pressure(struct sock *sk)
1127 int *memory_pressure = sk->sk_prot->memory_pressure;
1129 if (!memory_pressure)
1130 return;
1132 if (*memory_pressure)
1133 *memory_pressure = 0;
1135 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1136 struct cg_proto *cg_proto = sk->sk_cgrp;
1137 struct proto *prot = sk->sk_prot;
1139 for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto))
1140 if (*cg_proto->memory_pressure)
1141 *cg_proto->memory_pressure = 0;
1146 static inline void sk_enter_memory_pressure(struct sock *sk)
1148 if (!sk->sk_prot->enter_memory_pressure)
1149 return;
1151 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1152 struct cg_proto *cg_proto = sk->sk_cgrp;
1153 struct proto *prot = sk->sk_prot;
1155 for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto))
1156 cg_proto->enter_memory_pressure(sk);
1159 sk->sk_prot->enter_memory_pressure(sk);
1162 static inline long sk_prot_mem_limits(const struct sock *sk, int index)
1164 long *prot = sk->sk_prot->sysctl_mem;
1165 if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1166 prot = sk->sk_cgrp->sysctl_mem;
1167 return prot[index];
1170 static inline void memcg_memory_allocated_add(struct cg_proto *prot,
1171 unsigned long amt,
1172 int *parent_status)
1174 struct res_counter *fail;
1175 int ret;
1177 ret = res_counter_charge_nofail(prot->memory_allocated,
1178 amt << PAGE_SHIFT, &fail);
1179 if (ret < 0)
1180 *parent_status = OVER_LIMIT;
1183 static inline void memcg_memory_allocated_sub(struct cg_proto *prot,
1184 unsigned long amt)
1186 res_counter_uncharge(prot->memory_allocated, amt << PAGE_SHIFT);
1189 static inline u64 memcg_memory_allocated_read(struct cg_proto *prot)
1191 u64 ret;
1192 ret = res_counter_read_u64(prot->memory_allocated, RES_USAGE);
1193 return ret >> PAGE_SHIFT;
1196 static inline long
1197 sk_memory_allocated(const struct sock *sk)
1199 struct proto *prot = sk->sk_prot;
1200 if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1201 return memcg_memory_allocated_read(sk->sk_cgrp);
1203 return atomic_long_read(prot->memory_allocated);
1206 static inline long
1207 sk_memory_allocated_add(struct sock *sk, int amt, int *parent_status)
1209 struct proto *prot = sk->sk_prot;
1211 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1212 memcg_memory_allocated_add(sk->sk_cgrp, amt, parent_status);
1213 /* update the root cgroup regardless */
1214 atomic_long_add_return(amt, prot->memory_allocated);
1215 return memcg_memory_allocated_read(sk->sk_cgrp);
1218 return atomic_long_add_return(amt, prot->memory_allocated);
1221 static inline void
1222 sk_memory_allocated_sub(struct sock *sk, int amt)
1224 struct proto *prot = sk->sk_prot;
1226 if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1227 memcg_memory_allocated_sub(sk->sk_cgrp, amt);
1229 atomic_long_sub(amt, prot->memory_allocated);
1232 static inline void sk_sockets_allocated_dec(struct sock *sk)
1234 struct proto *prot = sk->sk_prot;
1236 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1237 struct cg_proto *cg_proto = sk->sk_cgrp;
1239 for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto))
1240 percpu_counter_dec(cg_proto->sockets_allocated);
1243 percpu_counter_dec(prot->sockets_allocated);
1246 static inline void sk_sockets_allocated_inc(struct sock *sk)
1248 struct proto *prot = sk->sk_prot;
1250 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1251 struct cg_proto *cg_proto = sk->sk_cgrp;
1253 for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto))
1254 percpu_counter_inc(cg_proto->sockets_allocated);
1257 percpu_counter_inc(prot->sockets_allocated);
1260 static inline int
1261 sk_sockets_allocated_read_positive(struct sock *sk)
1263 struct proto *prot = sk->sk_prot;
1265 if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1266 return percpu_counter_read_positive(sk->sk_cgrp->sockets_allocated);
1268 return percpu_counter_read_positive(prot->sockets_allocated);
1271 static inline int
1272 proto_sockets_allocated_sum_positive(struct proto *prot)
1274 return percpu_counter_sum_positive(prot->sockets_allocated);
1277 static inline long
1278 proto_memory_allocated(struct proto *prot)
1280 return atomic_long_read(prot->memory_allocated);
1283 static inline bool
1284 proto_memory_pressure(struct proto *prot)
1286 if (!prot->memory_pressure)
1287 return false;
1288 return !!*prot->memory_pressure;
1292 #ifdef CONFIG_PROC_FS
1293 /* Called with local bh disabled */
1294 extern void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc);
1295 extern int sock_prot_inuse_get(struct net *net, struct proto *proto);
1296 #else
1297 static inline void sock_prot_inuse_add(struct net *net, struct proto *prot,
1298 int inc)
1301 #endif
1304 /* With per-bucket locks this operation is not-atomic, so that
1305 * this version is not worse.
1307 static inline void __sk_prot_rehash(struct sock *sk)
1309 sk->sk_prot->unhash(sk);
1310 sk->sk_prot->hash(sk);
1313 void sk_prot_clear_portaddr_nulls(struct sock *sk, int size);
1315 /* About 10 seconds */
1316 #define SOCK_DESTROY_TIME (10*HZ)
1318 /* Sockets 0-1023 can't be bound to unless you are superuser */
1319 #define PROT_SOCK 1024
1321 #define SHUTDOWN_MASK 3
1322 #define RCV_SHUTDOWN 1
1323 #define SEND_SHUTDOWN 2
1325 #define SOCK_SNDBUF_LOCK 1
1326 #define SOCK_RCVBUF_LOCK 2
1327 #define SOCK_BINDADDR_LOCK 4
1328 #define SOCK_BINDPORT_LOCK 8
1330 /* sock_iocb: used to kick off async processing of socket ios */
1331 struct sock_iocb {
1332 struct list_head list;
1334 int flags;
1335 int size;
1336 struct socket *sock;
1337 struct sock *sk;
1338 struct scm_cookie *scm;
1339 struct msghdr *msg, async_msg;
1340 struct kiocb *kiocb;
1343 static inline struct sock_iocb *kiocb_to_siocb(struct kiocb *iocb)
1345 return (struct sock_iocb *)iocb->private;
1348 static inline struct kiocb *siocb_to_kiocb(struct sock_iocb *si)
1350 return si->kiocb;
1353 struct socket_alloc {
1354 struct socket socket;
1355 struct inode vfs_inode;
1358 static inline struct socket *SOCKET_I(struct inode *inode)
1360 return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
1363 static inline struct inode *SOCK_INODE(struct socket *socket)
1365 return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
1369 * Functions for memory accounting
1371 extern int __sk_mem_schedule(struct sock *sk, int size, int kind);
1372 extern void __sk_mem_reclaim(struct sock *sk);
1374 #define SK_MEM_QUANTUM ((int)PAGE_SIZE)
1375 #define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM)
1376 #define SK_MEM_SEND 0
1377 #define SK_MEM_RECV 1
1379 static inline int sk_mem_pages(int amt)
1381 return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT;
1384 static inline bool sk_has_account(struct sock *sk)
1386 /* return true if protocol supports memory accounting */
1387 return !!sk->sk_prot->memory_allocated;
1390 static inline bool sk_wmem_schedule(struct sock *sk, int size)
1392 if (!sk_has_account(sk))
1393 return true;
1394 return size <= sk->sk_forward_alloc ||
1395 __sk_mem_schedule(sk, size, SK_MEM_SEND);
1398 static inline bool
1399 sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size)
1401 if (!sk_has_account(sk))
1402 return true;
1403 return size<= sk->sk_forward_alloc ||
1404 __sk_mem_schedule(sk, size, SK_MEM_RECV) ||
1405 skb_pfmemalloc(skb);
1408 static inline void sk_mem_reclaim(struct sock *sk)
1410 if (!sk_has_account(sk))
1411 return;
1412 if (sk->sk_forward_alloc >= SK_MEM_QUANTUM)
1413 __sk_mem_reclaim(sk);
1416 static inline void sk_mem_reclaim_partial(struct sock *sk)
1418 if (!sk_has_account(sk))
1419 return;
1420 if (sk->sk_forward_alloc > SK_MEM_QUANTUM)
1421 __sk_mem_reclaim(sk);
1424 static inline void sk_mem_charge(struct sock *sk, int size)
1426 if (!sk_has_account(sk))
1427 return;
1428 sk->sk_forward_alloc -= size;
1431 static inline void sk_mem_uncharge(struct sock *sk, int size)
1433 if (!sk_has_account(sk))
1434 return;
1435 sk->sk_forward_alloc += size;
1438 static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb)
1440 sock_set_flag(sk, SOCK_QUEUE_SHRUNK);
1441 sk->sk_wmem_queued -= skb->truesize;
1442 sk_mem_uncharge(sk, skb->truesize);
1443 __kfree_skb(skb);
1446 /* Used by processes to "lock" a socket state, so that
1447 * interrupts and bottom half handlers won't change it
1448 * from under us. It essentially blocks any incoming
1449 * packets, so that we won't get any new data or any
1450 * packets that change the state of the socket.
1452 * While locked, BH processing will add new packets to
1453 * the backlog queue. This queue is processed by the
1454 * owner of the socket lock right before it is released.
1456 * Since ~2.3.5 it is also exclusive sleep lock serializing
1457 * accesses from user process context.
1459 #define sock_owned_by_user(sk) ((sk)->sk_lock.owned)
1461 static inline void sock_release_ownership(struct sock *sk)
1463 sk->sk_lock.owned = 0;
1467 * Macro so as to not evaluate some arguments when
1468 * lockdep is not enabled.
1470 * Mark both the sk_lock and the sk_lock.slock as a
1471 * per-address-family lock class.
1473 #define sock_lock_init_class_and_name(sk, sname, skey, name, key) \
1474 do { \
1475 sk->sk_lock.owned = 0; \
1476 init_waitqueue_head(&sk->sk_lock.wq); \
1477 spin_lock_init(&(sk)->sk_lock.slock); \
1478 debug_check_no_locks_freed((void *)&(sk)->sk_lock, \
1479 sizeof((sk)->sk_lock)); \
1480 lockdep_set_class_and_name(&(sk)->sk_lock.slock, \
1481 (skey), (sname)); \
1482 lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \
1483 } while (0)
1485 extern void lock_sock_nested(struct sock *sk, int subclass);
1487 static inline void lock_sock(struct sock *sk)
1489 lock_sock_nested(sk, 0);
1492 extern void release_sock(struct sock *sk);
1494 /* BH context may only use the following locking interface. */
1495 #define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock))
1496 #define bh_lock_sock_nested(__sk) \
1497 spin_lock_nested(&((__sk)->sk_lock.slock), \
1498 SINGLE_DEPTH_NESTING)
1499 #define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock))
1501 extern bool lock_sock_fast(struct sock *sk);
1503 * unlock_sock_fast - complement of lock_sock_fast
1504 * @sk: socket
1505 * @slow: slow mode
1507 * fast unlock socket for user context.
1508 * If slow mode is on, we call regular release_sock()
1510 static inline void unlock_sock_fast(struct sock *sk, bool slow)
1512 if (slow)
1513 release_sock(sk);
1514 else
1515 spin_unlock_bh(&sk->sk_lock.slock);
1519 extern struct sock *sk_alloc(struct net *net, int family,
1520 gfp_t priority,
1521 struct proto *prot);
1522 extern void sk_free(struct sock *sk);
1523 extern void sk_release_kernel(struct sock *sk);
1524 extern struct sock *sk_clone_lock(const struct sock *sk,
1525 const gfp_t priority);
1527 extern struct sk_buff *sock_wmalloc(struct sock *sk,
1528 unsigned long size, int force,
1529 gfp_t priority);
1530 extern struct sk_buff *sock_rmalloc(struct sock *sk,
1531 unsigned long size, int force,
1532 gfp_t priority);
1533 extern void sock_wfree(struct sk_buff *skb);
1534 extern void skb_orphan_partial(struct sk_buff *skb);
1535 extern void sock_rfree(struct sk_buff *skb);
1536 extern void sock_edemux(struct sk_buff *skb);
1538 extern int sock_setsockopt(struct socket *sock, int level,
1539 int op, char __user *optval,
1540 unsigned int optlen);
1542 extern int sock_getsockopt(struct socket *sock, int level,
1543 int op, char __user *optval,
1544 int __user *optlen);
1545 extern struct sk_buff *sock_alloc_send_skb(struct sock *sk,
1546 unsigned long size,
1547 int noblock,
1548 int *errcode);
1549 extern struct sk_buff *sock_alloc_send_pskb(struct sock *sk,
1550 unsigned long header_len,
1551 unsigned long data_len,
1552 int noblock,
1553 int *errcode,
1554 int max_page_order);
1555 extern void *sock_kmalloc(struct sock *sk, int size,
1556 gfp_t priority);
1557 extern void sock_kfree_s(struct sock *sk, void *mem, int size);
1558 extern void sk_send_sigurg(struct sock *sk);
1561 * Functions to fill in entries in struct proto_ops when a protocol
1562 * does not implement a particular function.
1564 extern int sock_no_bind(struct socket *,
1565 struct sockaddr *, int);
1566 extern int sock_no_connect(struct socket *,
1567 struct sockaddr *, int, int);
1568 extern int sock_no_socketpair(struct socket *,
1569 struct socket *);
1570 extern int sock_no_accept(struct socket *,
1571 struct socket *, int);
1572 extern int sock_no_getname(struct socket *,
1573 struct sockaddr *, int *, int);
1574 extern unsigned int sock_no_poll(struct file *, struct socket *,
1575 struct poll_table_struct *);
1576 extern int sock_no_ioctl(struct socket *, unsigned int,
1577 unsigned long);
1578 extern int sock_no_listen(struct socket *, int);
1579 extern int sock_no_shutdown(struct socket *, int);
1580 extern int sock_no_getsockopt(struct socket *, int , int,
1581 char __user *, int __user *);
1582 extern int sock_no_setsockopt(struct socket *, int, int,
1583 char __user *, unsigned int);
1584 extern int sock_no_sendmsg(struct kiocb *, struct socket *,
1585 struct msghdr *, size_t);
1586 extern int sock_no_recvmsg(struct kiocb *, struct socket *,
1587 struct msghdr *, size_t, int);
1588 extern int sock_no_mmap(struct file *file,
1589 struct socket *sock,
1590 struct vm_area_struct *vma);
1591 extern ssize_t sock_no_sendpage(struct socket *sock,
1592 struct page *page,
1593 int offset, size_t size,
1594 int flags);
1597 * Functions to fill in entries in struct proto_ops when a protocol
1598 * uses the inet style.
1600 extern int sock_common_getsockopt(struct socket *sock, int level, int optname,
1601 char __user *optval, int __user *optlen);
1602 extern int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock,
1603 struct msghdr *msg, size_t size, int flags);
1604 extern int sock_common_setsockopt(struct socket *sock, int level, int optname,
1605 char __user *optval, unsigned int optlen);
1606 extern int compat_sock_common_getsockopt(struct socket *sock, int level,
1607 int optname, char __user *optval, int __user *optlen);
1608 extern int compat_sock_common_setsockopt(struct socket *sock, int level,
1609 int optname, char __user *optval, unsigned int optlen);
1611 extern void sk_common_release(struct sock *sk);
1614 * Default socket callbacks and setup code
1617 /* Initialise core socket variables */
1618 extern void sock_init_data(struct socket *sock, struct sock *sk);
1620 extern void sk_filter_release_rcu(struct rcu_head *rcu);
1623 * sk_filter_release - release a socket filter
1624 * @fp: filter to remove
1626 * Remove a filter from a socket and release its resources.
1629 static inline void sk_filter_release(struct sk_filter *fp)
1631 if (atomic_dec_and_test(&fp->refcnt))
1632 call_rcu(&fp->rcu, sk_filter_release_rcu);
1635 static inline void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp)
1637 atomic_sub(sk_filter_size(fp->len), &sk->sk_omem_alloc);
1638 sk_filter_release(fp);
1641 static inline void sk_filter_charge(struct sock *sk, struct sk_filter *fp)
1643 atomic_inc(&fp->refcnt);
1644 atomic_add(sk_filter_size(fp->len), &sk->sk_omem_alloc);
1648 * Socket reference counting postulates.
1650 * * Each user of socket SHOULD hold a reference count.
1651 * * Each access point to socket (an hash table bucket, reference from a list,
1652 * running timer, skb in flight MUST hold a reference count.
1653 * * When reference count hits 0, it means it will never increase back.
1654 * * When reference count hits 0, it means that no references from
1655 * outside exist to this socket and current process on current CPU
1656 * is last user and may/should destroy this socket.
1657 * * sk_free is called from any context: process, BH, IRQ. When
1658 * it is called, socket has no references from outside -> sk_free
1659 * may release descendant resources allocated by the socket, but
1660 * to the time when it is called, socket is NOT referenced by any
1661 * hash tables, lists etc.
1662 * * Packets, delivered from outside (from network or from another process)
1663 * and enqueued on receive/error queues SHOULD NOT grab reference count,
1664 * when they sit in queue. Otherwise, packets will leak to hole, when
1665 * socket is looked up by one cpu and unhasing is made by another CPU.
1666 * It is true for udp/raw, netlink (leak to receive and error queues), tcp
1667 * (leak to backlog). Packet socket does all the processing inside
1668 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
1669 * use separate SMP lock, so that they are prone too.
1672 /* Ungrab socket and destroy it, if it was the last reference. */
1673 static inline void sock_put(struct sock *sk)
1675 if (atomic_dec_and_test(&sk->sk_refcnt))
1676 sk_free(sk);
1679 extern int sk_receive_skb(struct sock *sk, struct sk_buff *skb,
1680 const int nested);
1682 static inline void sk_tx_queue_set(struct sock *sk, int tx_queue)
1684 sk->sk_tx_queue_mapping = tx_queue;
1687 static inline void sk_tx_queue_clear(struct sock *sk)
1689 sk->sk_tx_queue_mapping = -1;
1692 static inline int sk_tx_queue_get(const struct sock *sk)
1694 return sk ? sk->sk_tx_queue_mapping : -1;
1697 static inline void sk_set_socket(struct sock *sk, struct socket *sock)
1699 sk_tx_queue_clear(sk);
1700 sk->sk_socket = sock;
1703 static inline wait_queue_head_t *sk_sleep(struct sock *sk)
1705 BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0);
1706 return &rcu_dereference_raw(sk->sk_wq)->wait;
1708 /* Detach socket from process context.
1709 * Announce socket dead, detach it from wait queue and inode.
1710 * Note that parent inode held reference count on this struct sock,
1711 * we do not release it in this function, because protocol
1712 * probably wants some additional cleanups or even continuing
1713 * to work with this socket (TCP).
1715 static inline void sock_orphan(struct sock *sk)
1717 write_lock_bh(&sk->sk_callback_lock);
1718 sock_set_flag(sk, SOCK_DEAD);
1719 sk_set_socket(sk, NULL);
1720 sk->sk_wq = NULL;
1721 write_unlock_bh(&sk->sk_callback_lock);
1724 static inline void sock_graft(struct sock *sk, struct socket *parent)
1726 write_lock_bh(&sk->sk_callback_lock);
1727 sk->sk_wq = parent->wq;
1728 parent->sk = sk;
1729 sk_set_socket(sk, parent);
1730 security_sock_graft(sk, parent);
1731 write_unlock_bh(&sk->sk_callback_lock);
1734 extern kuid_t sock_i_uid(struct sock *sk);
1735 extern unsigned long sock_i_ino(struct sock *sk);
1737 static inline struct dst_entry *
1738 __sk_dst_get(struct sock *sk)
1740 return rcu_dereference_check(sk->sk_dst_cache, sock_owned_by_user(sk) ||
1741 lockdep_is_held(&sk->sk_lock.slock));
1744 static inline struct dst_entry *
1745 sk_dst_get(struct sock *sk)
1747 struct dst_entry *dst;
1749 rcu_read_lock();
1750 dst = rcu_dereference(sk->sk_dst_cache);
1751 if (dst && !atomic_inc_not_zero(&dst->__refcnt))
1752 dst = NULL;
1753 rcu_read_unlock();
1754 return dst;
1757 extern void sk_reset_txq(struct sock *sk);
1759 static inline void dst_negative_advice(struct sock *sk)
1761 struct dst_entry *ndst, *dst = __sk_dst_get(sk);
1763 if (dst && dst->ops->negative_advice) {
1764 ndst = dst->ops->negative_advice(dst);
1766 if (ndst != dst) {
1767 rcu_assign_pointer(sk->sk_dst_cache, ndst);
1768 sk_reset_txq(sk);
1773 static inline void
1774 __sk_dst_set(struct sock *sk, struct dst_entry *dst)
1776 struct dst_entry *old_dst;
1778 sk_tx_queue_clear(sk);
1780 * This can be called while sk is owned by the caller only,
1781 * with no state that can be checked in a rcu_dereference_check() cond
1783 old_dst = rcu_dereference_raw(sk->sk_dst_cache);
1784 rcu_assign_pointer(sk->sk_dst_cache, dst);
1785 dst_release(old_dst);
1788 static inline void
1789 sk_dst_set(struct sock *sk, struct dst_entry *dst)
1791 struct dst_entry *old_dst;
1793 sk_tx_queue_clear(sk);
1794 old_dst = xchg(&sk->sk_dst_cache, dst);
1795 dst_release(old_dst);
1798 static inline void
1799 __sk_dst_reset(struct sock *sk)
1801 __sk_dst_set(sk, NULL);
1804 static inline void
1805 sk_dst_reset(struct sock *sk)
1807 sk_dst_set(sk, NULL);
1810 extern struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
1812 extern struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
1814 static inline bool sk_can_gso(const struct sock *sk)
1816 return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type);
1819 extern void sk_setup_caps(struct sock *sk, struct dst_entry *dst);
1821 static inline void sk_nocaps_add(struct sock *sk, netdev_features_t flags)
1823 sk->sk_route_nocaps |= flags;
1824 sk->sk_route_caps &= ~flags;
1827 static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
1828 char __user *from, char *to,
1829 int copy, int offset)
1831 if (skb->ip_summed == CHECKSUM_NONE) {
1832 int err = 0;
1833 __wsum csum = csum_and_copy_from_user(from, to, copy, 0, &err);
1834 if (err)
1835 return err;
1836 skb->csum = csum_block_add(skb->csum, csum, offset);
1837 } else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
1838 if (!access_ok(VERIFY_READ, from, copy) ||
1839 __copy_from_user_nocache(to, from, copy))
1840 return -EFAULT;
1841 } else if (copy_from_user(to, from, copy))
1842 return -EFAULT;
1844 return 0;
1847 static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
1848 char __user *from, int copy)
1850 int err, offset = skb->len;
1852 err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy),
1853 copy, offset);
1854 if (err)
1855 __skb_trim(skb, offset);
1857 return err;
1860 static inline int skb_copy_to_page_nocache(struct sock *sk, char __user *from,
1861 struct sk_buff *skb,
1862 struct page *page,
1863 int off, int copy)
1865 int err;
1867 err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off,
1868 copy, skb->len);
1869 if (err)
1870 return err;
1872 skb->len += copy;
1873 skb->data_len += copy;
1874 skb->truesize += copy;
1875 sk->sk_wmem_queued += copy;
1876 sk_mem_charge(sk, copy);
1877 return 0;
1880 static inline int skb_copy_to_page(struct sock *sk, char __user *from,
1881 struct sk_buff *skb, struct page *page,
1882 int off, int copy)
1884 if (skb->ip_summed == CHECKSUM_NONE) {
1885 int err = 0;
1886 __wsum csum = csum_and_copy_from_user(from,
1887 page_address(page) + off,
1888 copy, 0, &err);
1889 if (err)
1890 return err;
1891 skb->csum = csum_block_add(skb->csum, csum, skb->len);
1892 } else if (copy_from_user(page_address(page) + off, from, copy))
1893 return -EFAULT;
1895 skb->len += copy;
1896 skb->data_len += copy;
1897 skb->truesize += copy;
1898 sk->sk_wmem_queued += copy;
1899 sk_mem_charge(sk, copy);
1900 return 0;
1904 * sk_wmem_alloc_get - returns write allocations
1905 * @sk: socket
1907 * Returns sk_wmem_alloc minus initial offset of one
1909 static inline int sk_wmem_alloc_get(const struct sock *sk)
1911 return atomic_read(&sk->sk_wmem_alloc) - 1;
1915 * sk_rmem_alloc_get - returns read allocations
1916 * @sk: socket
1918 * Returns sk_rmem_alloc
1920 static inline int sk_rmem_alloc_get(const struct sock *sk)
1922 return atomic_read(&sk->sk_rmem_alloc);
1926 * sk_has_allocations - check if allocations are outstanding
1927 * @sk: socket
1929 * Returns true if socket has write or read allocations
1931 static inline bool sk_has_allocations(const struct sock *sk)
1933 return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk);
1937 * wq_has_sleeper - check if there are any waiting processes
1938 * @wq: struct socket_wq
1940 * Returns true if socket_wq has waiting processes
1942 * The purpose of the wq_has_sleeper and sock_poll_wait is to wrap the memory
1943 * barrier call. They were added due to the race found within the tcp code.
1945 * Consider following tcp code paths:
1947 * CPU1 CPU2
1949 * sys_select receive packet
1950 * ... ...
1951 * __add_wait_queue update tp->rcv_nxt
1952 * ... ...
1953 * tp->rcv_nxt check sock_def_readable
1954 * ... {
1955 * schedule rcu_read_lock();
1956 * wq = rcu_dereference(sk->sk_wq);
1957 * if (wq && waitqueue_active(&wq->wait))
1958 * wake_up_interruptible(&wq->wait)
1959 * ...
1962 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
1963 * in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1
1964 * could then endup calling schedule and sleep forever if there are no more
1965 * data on the socket.
1968 static inline bool wq_has_sleeper(struct socket_wq *wq)
1970 /* We need to be sure we are in sync with the
1971 * add_wait_queue modifications to the wait queue.
1973 * This memory barrier is paired in the sock_poll_wait.
1975 smp_mb();
1976 return wq && waitqueue_active(&wq->wait);
1980 * sock_poll_wait - place memory barrier behind the poll_wait call.
1981 * @filp: file
1982 * @wait_address: socket wait queue
1983 * @p: poll_table
1985 * See the comments in the wq_has_sleeper function.
1987 static inline void sock_poll_wait(struct file *filp,
1988 wait_queue_head_t *wait_address, poll_table *p)
1990 if (!poll_does_not_wait(p) && wait_address) {
1991 poll_wait(filp, wait_address, p);
1992 /* We need to be sure we are in sync with the
1993 * socket flags modification.
1995 * This memory barrier is paired in the wq_has_sleeper.
1997 smp_mb();
2002 * Queue a received datagram if it will fit. Stream and sequenced
2003 * protocols can't normally use this as they need to fit buffers in
2004 * and play with them.
2006 * Inlined as it's very short and called for pretty much every
2007 * packet ever received.
2010 static inline void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
2012 skb_orphan(skb);
2013 skb->sk = sk;
2014 skb->destructor = sock_wfree;
2016 * We used to take a refcount on sk, but following operation
2017 * is enough to guarantee sk_free() wont free this sock until
2018 * all in-flight packets are completed
2020 atomic_add(skb->truesize, &sk->sk_wmem_alloc);
2023 static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
2025 skb_orphan(skb);
2026 skb->sk = sk;
2027 skb->destructor = sock_rfree;
2028 atomic_add(skb->truesize, &sk->sk_rmem_alloc);
2029 sk_mem_charge(sk, skb->truesize);
2032 extern void sk_reset_timer(struct sock *sk, struct timer_list *timer,
2033 unsigned long expires);
2035 extern void sk_stop_timer(struct sock *sk, struct timer_list *timer);
2037 extern int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
2039 extern int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
2042 * Recover an error report and clear atomically
2045 static inline int sock_error(struct sock *sk)
2047 int err;
2048 if (likely(!sk->sk_err))
2049 return 0;
2050 err = xchg(&sk->sk_err, 0);
2051 return -err;
2054 static inline unsigned long sock_wspace(struct sock *sk)
2056 int amt = 0;
2058 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
2059 amt = sk->sk_sndbuf - atomic_read(&sk->sk_wmem_alloc);
2060 if (amt < 0)
2061 amt = 0;
2063 return amt;
2066 static inline void sk_wake_async(struct sock *sk, int how, int band)
2068 if (sock_flag(sk, SOCK_FASYNC))
2069 sock_wake_async(sk->sk_socket, how, band);
2072 /* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might
2073 * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak.
2074 * Note: for send buffers, TCP works better if we can build two skbs at
2075 * minimum.
2077 #define TCP_SKB_MIN_TRUESIZE (2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff)))
2079 #define SOCK_MIN_SNDBUF (TCP_SKB_MIN_TRUESIZE * 2)
2080 #define SOCK_MIN_RCVBUF TCP_SKB_MIN_TRUESIZE
2082 static inline void sk_stream_moderate_sndbuf(struct sock *sk)
2084 if (!(sk->sk_userlocks & SOCK_SNDBUF_LOCK)) {
2085 sk->sk_sndbuf = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
2086 sk->sk_sndbuf = max_t(u32, sk->sk_sndbuf, SOCK_MIN_SNDBUF);
2090 struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp);
2093 * sk_page_frag - return an appropriate page_frag
2094 * @sk: socket
2096 * If socket allocation mode allows current thread to sleep, it means its
2097 * safe to use the per task page_frag instead of the per socket one.
2099 static inline struct page_frag *sk_page_frag(struct sock *sk)
2101 if (sk->sk_allocation & __GFP_WAIT)
2102 return &current->task_frag;
2104 return &sk->sk_frag;
2107 extern bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag);
2110 * Default write policy as shown to user space via poll/select/SIGIO
2112 static inline bool sock_writeable(const struct sock *sk)
2114 return atomic_read(&sk->sk_wmem_alloc) < (sk->sk_sndbuf >> 1);
2117 static inline gfp_t gfp_any(void)
2119 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2122 static inline long sock_rcvtimeo(const struct sock *sk, bool noblock)
2124 return noblock ? 0 : sk->sk_rcvtimeo;
2127 static inline long sock_sndtimeo(const struct sock *sk, bool noblock)
2129 return noblock ? 0 : sk->sk_sndtimeo;
2132 static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
2134 return (waitall ? len : min_t(int, sk->sk_rcvlowat, len)) ? : 1;
2137 /* Alas, with timeout socket operations are not restartable.
2138 * Compare this to poll().
2140 static inline int sock_intr_errno(long timeo)
2142 return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
2145 extern void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
2146 struct sk_buff *skb);
2147 extern void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
2148 struct sk_buff *skb);
2150 static inline void
2151 sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
2153 ktime_t kt = skb->tstamp;
2154 struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
2157 * generate control messages if
2158 * - receive time stamping in software requested (SOCK_RCVTSTAMP
2159 * or SOCK_TIMESTAMPING_RX_SOFTWARE)
2160 * - software time stamp available and wanted
2161 * (SOCK_TIMESTAMPING_SOFTWARE)
2162 * - hardware time stamps available and wanted
2163 * (SOCK_TIMESTAMPING_SYS_HARDWARE or
2164 * SOCK_TIMESTAMPING_RAW_HARDWARE)
2166 if (sock_flag(sk, SOCK_RCVTSTAMP) ||
2167 sock_flag(sk, SOCK_TIMESTAMPING_RX_SOFTWARE) ||
2168 (kt.tv64 && sock_flag(sk, SOCK_TIMESTAMPING_SOFTWARE)) ||
2169 (hwtstamps->hwtstamp.tv64 &&
2170 sock_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE)) ||
2171 (hwtstamps->syststamp.tv64 &&
2172 sock_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE)))
2173 __sock_recv_timestamp(msg, sk, skb);
2174 else
2175 sk->sk_stamp = kt;
2177 if (sock_flag(sk, SOCK_WIFI_STATUS) && skb->wifi_acked_valid)
2178 __sock_recv_wifi_status(msg, sk, skb);
2181 extern void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2182 struct sk_buff *skb);
2184 static inline void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2185 struct sk_buff *skb)
2187 #define FLAGS_TS_OR_DROPS ((1UL << SOCK_RXQ_OVFL) | \
2188 (1UL << SOCK_RCVTSTAMP) | \
2189 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE) | \
2190 (1UL << SOCK_TIMESTAMPING_SOFTWARE) | \
2191 (1UL << SOCK_TIMESTAMPING_RAW_HARDWARE) | \
2192 (1UL << SOCK_TIMESTAMPING_SYS_HARDWARE))
2194 if (sk->sk_flags & FLAGS_TS_OR_DROPS)
2195 __sock_recv_ts_and_drops(msg, sk, skb);
2196 else
2197 sk->sk_stamp = skb->tstamp;
2201 * sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
2202 * @sk: socket sending this packet
2203 * @tx_flags: filled with instructions for time stamping
2205 * Currently only depends on SOCK_TIMESTAMPING* flags.
2207 extern void sock_tx_timestamp(struct sock *sk, __u8 *tx_flags);
2210 * sk_eat_skb - Release a skb if it is no longer needed
2211 * @sk: socket to eat this skb from
2212 * @skb: socket buffer to eat
2213 * @copied_early: flag indicating whether DMA operations copied this data early
2215 * This routine must be called with interrupts disabled or with the socket
2216 * locked so that the sk_buff queue operation is ok.
2218 #ifdef CONFIG_NET_DMA
2219 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb, bool copied_early)
2221 __skb_unlink(skb, &sk->sk_receive_queue);
2222 if (!copied_early)
2223 __kfree_skb(skb);
2224 else
2225 __skb_queue_tail(&sk->sk_async_wait_queue, skb);
2227 #else
2228 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb, bool copied_early)
2230 __skb_unlink(skb, &sk->sk_receive_queue);
2231 __kfree_skb(skb);
2233 #endif
2235 static inline
2236 struct net *sock_net(const struct sock *sk)
2238 return read_pnet(&sk->sk_net);
2241 static inline
2242 void sock_net_set(struct sock *sk, struct net *net)
2244 write_pnet(&sk->sk_net, net);
2248 * Kernel sockets, f.e. rtnl or icmp_socket, are a part of a namespace.
2249 * They should not hold a reference to a namespace in order to allow
2250 * to stop it.
2251 * Sockets after sk_change_net should be released using sk_release_kernel
2253 static inline void sk_change_net(struct sock *sk, struct net *net)
2255 put_net(sock_net(sk));
2256 sock_net_set(sk, hold_net(net));
2259 static inline struct sock *skb_steal_sock(struct sk_buff *skb)
2261 if (skb->sk) {
2262 struct sock *sk = skb->sk;
2264 skb->destructor = NULL;
2265 skb->sk = NULL;
2266 return sk;
2268 return NULL;
2271 extern void sock_enable_timestamp(struct sock *sk, int flag);
2272 extern int sock_get_timestamp(struct sock *, struct timeval __user *);
2273 extern int sock_get_timestampns(struct sock *, struct timespec __user *);
2274 extern int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
2275 int level, int type);
2277 bool sk_ns_capable(const struct sock *sk,
2278 struct user_namespace *user_ns, int cap);
2279 bool sk_capable(const struct sock *sk, int cap);
2280 bool sk_net_capable(const struct sock *sk, int cap);
2283 * Enable debug/info messages
2285 extern int net_msg_warn;
2286 #define NETDEBUG(fmt, args...) \
2287 do { if (net_msg_warn) printk(fmt,##args); } while (0)
2289 #define LIMIT_NETDEBUG(fmt, args...) \
2290 do { if (net_msg_warn && net_ratelimit()) printk(fmt,##args); } while(0)
2292 extern __u32 sysctl_wmem_max;
2293 extern __u32 sysctl_rmem_max;
2295 extern int sysctl_optmem_max;
2297 extern __u32 sysctl_wmem_default;
2298 extern __u32 sysctl_rmem_default;
2300 #endif /* _SOCK_H */