memcg: rename config variables
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / include / net / sock.h
CommitLineData
1da177e4
LT
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 *
02c30a84 10 * Authors: Ross Biro
1da177e4
LT
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
a6b7a407 43#include <linux/hardirq.h>
172589cc 44#include <linux/kernel.h>
1da177e4 45#include <linux/list.h>
88ab1932 46#include <linux/list_nulls.h>
1da177e4
LT
47#include <linux/timer.h>
48#include <linux/cache.h>
3f134619 49#include <linux/bitops.h>
a5b5bb9a 50#include <linux/lockdep.h>
1da177e4
LT
51#include <linux/netdevice.h>
52#include <linux/skbuff.h> /* struct sk_buff */
d7fe0f24 53#include <linux/mm.h>
1da177e4 54#include <linux/security.h>
5a0e3ad6 55#include <linux/slab.h>
c6e1a0d1 56#include <linux/uaccess.h>
180d8cd9 57#include <linux/memcontrol.h>
e1aab161 58#include <linux/res_counter.h>
c5905afb 59#include <linux/static_key.h>
40401530
AV
60#include <linux/aio.h>
61#include <linux/sched.h>
1da177e4
LT
62
63#include <linux/filter.h>
88ab1932 64#include <linux/rculist_nulls.h>
a57de0b4 65#include <linux/poll.h>
1da177e4 66
c31504dc 67#include <linux/atomic.h>
1da177e4
LT
68#include <net/dst.h>
69#include <net/checksum.h>
70
9f048bfb
ED
71struct cgroup;
72struct cgroup_subsys;
c607b2ed 73#ifdef CONFIG_NET
1d62e436
GC
74int mem_cgroup_sockets_init(struct mem_cgroup *memcg, struct cgroup_subsys *ss);
75void mem_cgroup_sockets_destroy(struct mem_cgroup *memcg);
c607b2ed
GC
76#else
77static inline
1d62e436 78int mem_cgroup_sockets_init(struct mem_cgroup *memcg, struct cgroup_subsys *ss)
c607b2ed
GC
79{
80 return 0;
81}
82static inline
1d62e436 83void mem_cgroup_sockets_destroy(struct mem_cgroup *memcg)
c607b2ed
GC
84{
85}
86#endif
1da177e4
LT
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
4cd9029d 99/* Validate arguments and do nothing */
b9075fa9 100static inline __printf(2, 3)
dc6b9b78 101void SOCK_DEBUG(const struct sock *sk, const char *msg, ...)
4cd9029d
SH
102{
103}
1da177e4
LT
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 */
1da177e4
LT
110typedef struct {
111 spinlock_t slock;
d2e9117c 112 int owned;
1da177e4 113 wait_queue_head_t wq;
a5b5bb9a
IM
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
1da177e4
LT
123} socket_lock_t;
124
1da177e4 125struct sock;
8feaf0c0 126struct proto;
0eeb8ffc 127struct net;
1da177e4
LT
128
129/**
4dc3b16b 130 * struct sock_common - minimal network layer representation of sockets
68835aba
ED
131 * @skc_daddr: Foreign IPv4 addr
132 * @skc_rcv_saddr: Bound local IPv4 addr
4dc6dc71 133 * @skc_hash: hash value used with various protocol lookup tables
d4cada4a 134 * @skc_u16hashes: two u16 hash values used by UDP lookup tables
4dc3b16b
PP
135 * @skc_family: network address family
136 * @skc_state: Connection state
137 * @skc_reuse: %SO_REUSEADDR setting
138 * @skc_bound_dev_if: bound device index if != 0
4dc3b16b 139 * @skc_bind_node: bind hash linkage for various protocol lookup tables
512615b6 140 * @skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol
8feaf0c0 141 * @skc_prot: protocol handlers inside a network family
07feaebf 142 * @skc_net: reference to the network namespace of this socket
68835aba
ED
143 * @skc_node: main hash linkage for various protocol lookup tables
144 * @skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol
145 * @skc_tx_queue_mapping: tx queue number for this connection
146 * @skc_refcnt: reference count
4dc3b16b
PP
147 *
148 * This is the minimal network layer representation of sockets, the header
8feaf0c0
ACM
149 * for struct sock and struct inet_timewait_sock.
150 */
1da177e4 151struct sock_common {
68835aba
ED
152 /* skc_daddr and skc_rcv_saddr must be grouped :
153 * cf INET_MATCH() and INET_TW_MATCH()
4dc6dc71 154 */
68835aba
ED
155 __be32 skc_daddr;
156 __be32 skc_rcv_saddr;
4dc6dc71 157
d4cada4a
ED
158 union {
159 unsigned int skc_hash;
160 __u16 skc_u16hashes[2];
161 };
4dc6dc71
ED
162 unsigned short skc_family;
163 volatile unsigned char skc_state;
164 unsigned char skc_reuse;
165 int skc_bound_dev_if;
512615b6
ED
166 union {
167 struct hlist_node skc_bind_node;
168 struct hlist_nulls_node skc_portaddr_node;
169 };
8feaf0c0 170 struct proto *skc_prot;
3b1e0a65 171#ifdef CONFIG_NET_NS
07feaebf 172 struct net *skc_net;
3b1e0a65 173#endif
68835aba
ED
174 /*
175 * fields between dontcopy_begin/dontcopy_end
176 * are not copied in sock_copy()
177 */
928c41e7 178 /* private: */
68835aba 179 int skc_dontcopy_begin[0];
928c41e7 180 /* public: */
68835aba
ED
181 union {
182 struct hlist_node skc_node;
183 struct hlist_nulls_node skc_nulls_node;
184 };
185 int skc_tx_queue_mapping;
186 atomic_t skc_refcnt;
928c41e7 187 /* private: */
68835aba 188 int skc_dontcopy_end[0];
928c41e7 189 /* public: */
1da177e4
LT
190};
191
e1aab161 192struct cg_proto;
1da177e4
LT
193/**
194 * struct sock - network layer representation of sockets
8feaf0c0 195 * @__sk_common: shared layout with inet_timewait_sock
4dc3b16b
PP
196 * @sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
197 * @sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
198 * @sk_lock: synchronizer
199 * @sk_rcvbuf: size of receive buffer in bytes
43815482 200 * @sk_wq: sock wait queue and async head
deaa5854 201 * @sk_rx_dst: receive input route used by early tcp demux
4dc3b16b
PP
202 * @sk_dst_cache: destination cache
203 * @sk_dst_lock: destination cache lock
204 * @sk_policy: flow policy
4dc3b16b
PP
205 * @sk_receive_queue: incoming packets
206 * @sk_wmem_alloc: transmit queue bytes committed
207 * @sk_write_queue: Packet sending queue
97fc2f08 208 * @sk_async_wait_queue: DMA copied packets
4dc3b16b
PP
209 * @sk_omem_alloc: "o" is "option" or "other"
210 * @sk_wmem_queued: persistent queue size
211 * @sk_forward_alloc: space allocated forward
212 * @sk_allocation: allocation mode
213 * @sk_sndbuf: size of send buffer in bytes
33c732c3 214 * @sk_flags: %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE,
20d49473 215 * %SO_OOBINLINE settings, %SO_TIMESTAMPING settings
4dc3b16b
PP
216 * @sk_no_check: %SO_NO_CHECK setting, wether or not checkup packets
217 * @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
a465419b 218 * @sk_route_nocaps: forbidden route capabilities (e.g NETIF_F_GSO_MASK)
bcd76111 219 * @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
82cc1a7a 220 * @sk_gso_max_size: Maximum GSO segment size to build
4dc3b16b 221 * @sk_lingertime: %SO_LINGER l_linger setting
4dc3b16b
PP
222 * @sk_backlog: always used with the per-socket spinlock held
223 * @sk_callback_lock: used with the callbacks in the end of this struct
224 * @sk_error_queue: rarely used
33c732c3
WC
225 * @sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt,
226 * IPV6_ADDRFORM for instance)
4dc3b16b 227 * @sk_err: last error
33c732c3
WC
228 * @sk_err_soft: errors that don't cause failure but are the cause of a
229 * persistent failure not just 'timed out'
cb61cb9b 230 * @sk_drops: raw/udp drops counter
4dc3b16b
PP
231 * @sk_ack_backlog: current listen backlog
232 * @sk_max_ack_backlog: listen backlog set in listen()
233 * @sk_priority: %SO_PRIORITY setting
1a3bc369 234 * @sk_cgrp_prioidx: socket group's priority map index
4dc3b16b
PP
235 * @sk_type: socket type (%SOCK_STREAM, etc)
236 * @sk_protocol: which protocol this socket belongs in this network family
53c3fa20
RD
237 * @sk_peer_pid: &struct pid for this socket's peer
238 * @sk_peer_cred: %SO_PEERCRED setting
4dc3b16b
PP
239 * @sk_rcvlowat: %SO_RCVLOWAT setting
240 * @sk_rcvtimeo: %SO_RCVTIMEO setting
241 * @sk_sndtimeo: %SO_SNDTIMEO setting
c58dc01b 242 * @sk_rxhash: flow hash received from netif layer
4dc3b16b
PP
243 * @sk_filter: socket filtering instructions
244 * @sk_protinfo: private area, net family specific, when not using slab
245 * @sk_timer: sock cleanup timer
246 * @sk_stamp: time stamp of last packet received
247 * @sk_socket: Identd and reporting IO signals
248 * @sk_user_data: RPC layer private data
249 * @sk_sndmsg_page: cached page for sendmsg
250 * @sk_sndmsg_off: cached offset for sendmsg
d3d4f0a0 251 * @sk_peek_off: current peek_offset value
4dc3b16b 252 * @sk_send_head: front of stuff to transmit
67be2dd1 253 * @sk_security: used by security modules
31729363 254 * @sk_mark: generic packet mark
53c3fa20 255 * @sk_classid: this socket's cgroup classid
e1aab161 256 * @sk_cgrp: this socket's cgroup-specific proto data
4dc3b16b
PP
257 * @sk_write_pending: a write to stream socket waits to start
258 * @sk_state_change: callback to indicate change in the state of the sock
259 * @sk_data_ready: callback to indicate there is data to be processed
260 * @sk_write_space: callback to indicate there is bf sending space available
261 * @sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
262 * @sk_backlog_rcv: callback to process the backlog
263 * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
1da177e4
LT
264 */
265struct sock {
266 /*
8feaf0c0 267 * Now struct inet_timewait_sock also uses sock_common, so please just
1da177e4
LT
268 * don't add nothing before this first member (__sk_common) --acme
269 */
270 struct sock_common __sk_common;
4dc6dc71
ED
271#define sk_node __sk_common.skc_node
272#define sk_nulls_node __sk_common.skc_nulls_node
273#define sk_refcnt __sk_common.skc_refcnt
e022f0b4 274#define sk_tx_queue_mapping __sk_common.skc_tx_queue_mapping
4dc6dc71 275
68835aba
ED
276#define sk_dontcopy_begin __sk_common.skc_dontcopy_begin
277#define sk_dontcopy_end __sk_common.skc_dontcopy_end
4dc6dc71 278#define sk_hash __sk_common.skc_hash
1da177e4
LT
279#define sk_family __sk_common.skc_family
280#define sk_state __sk_common.skc_state
281#define sk_reuse __sk_common.skc_reuse
282#define sk_bound_dev_if __sk_common.skc_bound_dev_if
1da177e4 283#define sk_bind_node __sk_common.skc_bind_node
8feaf0c0 284#define sk_prot __sk_common.skc_prot
07feaebf 285#define sk_net __sk_common.skc_net
1da177e4 286 socket_lock_t sk_lock;
b178bb3d 287 struct sk_buff_head sk_receive_queue;
fa438ccf
ED
288 /*
289 * The backlog queue is special, it is always used with
290 * the per-socket spinlock held and requires low latency
291 * access. Therefore we special case it's implementation.
b178bb3d
ED
292 * Note : rmem_alloc is in this structure to fill a hole
293 * on 64bit arches, not because its logically part of
294 * backlog.
fa438ccf
ED
295 */
296 struct {
b178bb3d
ED
297 atomic_t rmem_alloc;
298 int len;
299 struct sk_buff *head;
300 struct sk_buff *tail;
fa438ccf 301 } sk_backlog;
b178bb3d
ED
302#define sk_rmem_alloc sk_backlog.rmem_alloc
303 int sk_forward_alloc;
304#ifdef CONFIG_RPS
305 __u32 sk_rxhash;
306#endif
307 atomic_t sk_drops;
308 int sk_rcvbuf;
309
310 struct sk_filter __rcu *sk_filter;
eaefd110 311 struct socket_wq __rcu *sk_wq;
b178bb3d
ED
312
313#ifdef CONFIG_NET_DMA
314 struct sk_buff_head sk_async_wait_queue;
315#endif
316
def8b4fa 317#ifdef CONFIG_XFRM
1da177e4 318 struct xfrm_policy *sk_policy[2];
def8b4fa 319#endif
b178bb3d 320 unsigned long sk_flags;
deaa5854 321 struct dst_entry *sk_rx_dst;
b178bb3d 322 struct dst_entry *sk_dst_cache;
b6c6712a 323 spinlock_t sk_dst_lock;
1da177e4
LT
324 atomic_t sk_wmem_alloc;
325 atomic_t sk_omem_alloc;
4e07a91c 326 int sk_sndbuf;
1da177e4 327 struct sk_buff_head sk_write_queue;
b178bb3d
ED
328 kmemcheck_bitfield_begin(flags);
329 unsigned int sk_shutdown : 2,
330 sk_no_check : 2,
331 sk_userlocks : 4,
332 sk_protocol : 8,
333 sk_type : 16;
334 kmemcheck_bitfield_end(flags);
1da177e4 335 int sk_wmem_queued;
7d877f3b 336 gfp_t sk_allocation;
c8f44aff
MM
337 netdev_features_t sk_route_caps;
338 netdev_features_t sk_route_nocaps;
bcd76111 339 int sk_gso_type;
82cc1a7a 340 unsigned int sk_gso_max_size;
9932cf95 341 int sk_rcvlowat;
1da177e4 342 unsigned long sk_lingertime;
1da177e4 343 struct sk_buff_head sk_error_queue;
476e19cf 344 struct proto *sk_prot_creator;
1da177e4
LT
345 rwlock_t sk_callback_lock;
346 int sk_err,
347 sk_err_soft;
348 unsigned short sk_ack_backlog;
349 unsigned short sk_max_ack_backlog;
350 __u32 sk_priority;
5bc1421e
NH
351#ifdef CONFIG_CGROUPS
352 __u32 sk_cgrp_prioidx;
353#endif
109f6e39
EB
354 struct pid *sk_peer_pid;
355 const struct cred *sk_peer_cred;
1da177e4
LT
356 long sk_rcvtimeo;
357 long sk_sndtimeo;
1da177e4
LT
358 void *sk_protinfo;
359 struct timer_list sk_timer;
b7aa0bf7 360 ktime_t sk_stamp;
1da177e4
LT
361 struct socket *sk_socket;
362 void *sk_user_data;
363 struct page *sk_sndmsg_page;
364 struct sk_buff *sk_send_head;
365 __u32 sk_sndmsg_off;
ef64a54f 366 __s32 sk_peek_off;
1da177e4 367 int sk_write_pending;
d5f64238 368#ifdef CONFIG_SECURITY
1da177e4 369 void *sk_security;
d5f64238 370#endif
4a19ec58 371 __u32 sk_mark;
f8451725 372 u32 sk_classid;
e1aab161 373 struct cg_proto *sk_cgrp;
1da177e4
LT
374 void (*sk_state_change)(struct sock *sk);
375 void (*sk_data_ready)(struct sock *sk, int bytes);
376 void (*sk_write_space)(struct sock *sk);
377 void (*sk_error_report)(struct sock *sk);
dc6b9b78
ED
378 int (*sk_backlog_rcv)(struct sock *sk,
379 struct sk_buff *skb);
1da177e4
LT
380 void (*sk_destruct)(struct sock *sk);
381};
382
4a17fd52
PE
383/*
384 * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK
385 * or not whether his port will be reused by someone else. SK_FORCE_REUSE
386 * on a socket means that the socket will reuse everybody else's port
387 * without looking at the other's sk_reuse value.
388 */
389
390#define SK_NO_REUSE 0
391#define SK_CAN_REUSE 1
392#define SK_FORCE_REUSE 2
393
ef64a54f
PE
394static inline int sk_peek_offset(struct sock *sk, int flags)
395{
396 if ((flags & MSG_PEEK) && (sk->sk_peek_off >= 0))
397 return sk->sk_peek_off;
398 else
399 return 0;
400}
401
402static inline void sk_peek_offset_bwd(struct sock *sk, int val)
403{
404 if (sk->sk_peek_off >= 0) {
405 if (sk->sk_peek_off >= val)
406 sk->sk_peek_off -= val;
407 else
408 sk->sk_peek_off = 0;
409 }
410}
411
412static inline void sk_peek_offset_fwd(struct sock *sk, int val)
413{
414 if (sk->sk_peek_off >= 0)
415 sk->sk_peek_off += val;
416}
417
1da177e4
LT
418/*
419 * Hashed lists helper routines
420 */
c4146644
LZ
421static inline struct sock *sk_entry(const struct hlist_node *node)
422{
423 return hlist_entry(node, struct sock, sk_node);
424}
425
e48c414e 426static inline struct sock *__sk_head(const struct hlist_head *head)
1da177e4
LT
427{
428 return hlist_entry(head->first, struct sock, sk_node);
429}
430
e48c414e 431static inline struct sock *sk_head(const struct hlist_head *head)
1da177e4
LT
432{
433 return hlist_empty(head) ? NULL : __sk_head(head);
434}
435
88ab1932
ED
436static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head)
437{
438 return hlist_nulls_entry(head->first, struct sock, sk_nulls_node);
439}
440
441static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head)
442{
443 return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head);
444}
445
e48c414e 446static inline struct sock *sk_next(const struct sock *sk)
1da177e4
LT
447{
448 return sk->sk_node.next ?
449 hlist_entry(sk->sk_node.next, struct sock, sk_node) : NULL;
450}
451
88ab1932
ED
452static inline struct sock *sk_nulls_next(const struct sock *sk)
453{
454 return (!is_a_nulls(sk->sk_nulls_node.next)) ?
455 hlist_nulls_entry(sk->sk_nulls_node.next,
456 struct sock, sk_nulls_node) :
457 NULL;
458}
459
dc6b9b78 460static inline bool sk_unhashed(const struct sock *sk)
1da177e4
LT
461{
462 return hlist_unhashed(&sk->sk_node);
463}
464
dc6b9b78 465static inline bool sk_hashed(const struct sock *sk)
1da177e4 466{
da753bea 467 return !sk_unhashed(sk);
1da177e4
LT
468}
469
dc6b9b78 470static inline void sk_node_init(struct hlist_node *node)
1da177e4
LT
471{
472 node->pprev = NULL;
473}
474
dc6b9b78 475static inline void sk_nulls_node_init(struct hlist_nulls_node *node)
88ab1932
ED
476{
477 node->pprev = NULL;
478}
479
dc6b9b78 480static inline void __sk_del_node(struct sock *sk)
1da177e4
LT
481{
482 __hlist_del(&sk->sk_node);
483}
484
808f5114 485/* NB: equivalent to hlist_del_init_rcu */
dc6b9b78 486static inline bool __sk_del_node_init(struct sock *sk)
1da177e4
LT
487{
488 if (sk_hashed(sk)) {
489 __sk_del_node(sk);
490 sk_node_init(&sk->sk_node);
dc6b9b78 491 return true;
1da177e4 492 }
dc6b9b78 493 return false;
1da177e4
LT
494}
495
496/* Grab socket reference count. This operation is valid only
497 when sk is ALREADY grabbed f.e. it is found in hash table
498 or a list and the lookup is made under lock preventing hash table
499 modifications.
500 */
501
502static inline void sock_hold(struct sock *sk)
503{
504 atomic_inc(&sk->sk_refcnt);
505}
506
507/* Ungrab socket in the context, which assumes that socket refcnt
508 cannot hit zero, f.e. it is true in context of any socketcall.
509 */
510static inline void __sock_put(struct sock *sk)
511{
512 atomic_dec(&sk->sk_refcnt);
513}
514
dc6b9b78 515static inline bool sk_del_node_init(struct sock *sk)
1da177e4 516{
dc6b9b78 517 bool rc = __sk_del_node_init(sk);
1da177e4
LT
518
519 if (rc) {
520 /* paranoid for a while -acme */
521 WARN_ON(atomic_read(&sk->sk_refcnt) == 1);
522 __sock_put(sk);
523 }
524 return rc;
525}
808f5114 526#define sk_del_node_init_rcu(sk) sk_del_node_init(sk)
1da177e4 527
dc6b9b78 528static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk)
271b72c7
ED
529{
530 if (sk_hashed(sk)) {
88ab1932 531 hlist_nulls_del_init_rcu(&sk->sk_nulls_node);
dc6b9b78 532 return true;
271b72c7 533 }
dc6b9b78 534 return false;
271b72c7
ED
535}
536
dc6b9b78 537static inline bool sk_nulls_del_node_init_rcu(struct sock *sk)
271b72c7 538{
dc6b9b78 539 bool rc = __sk_nulls_del_node_init_rcu(sk);
271b72c7
ED
540
541 if (rc) {
542 /* paranoid for a while -acme */
543 WARN_ON(atomic_read(&sk->sk_refcnt) == 1);
544 __sock_put(sk);
545 }
546 return rc;
547}
548
dc6b9b78 549static inline void __sk_add_node(struct sock *sk, struct hlist_head *list)
1da177e4
LT
550{
551 hlist_add_head(&sk->sk_node, list);
552}
553
dc6b9b78 554static inline void sk_add_node(struct sock *sk, struct hlist_head *list)
1da177e4
LT
555{
556 sock_hold(sk);
557 __sk_add_node(sk, list);
558}
559
dc6b9b78 560static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list)
808f5114 561{
562 sock_hold(sk);
563 hlist_add_head_rcu(&sk->sk_node, list);
564}
565
dc6b9b78 566static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
271b72c7 567{
88ab1932 568 hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list);
271b72c7
ED
569}
570
dc6b9b78 571static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
271b72c7
ED
572{
573 sock_hold(sk);
88ab1932 574 __sk_nulls_add_node_rcu(sk, list);
271b72c7
ED
575}
576
dc6b9b78 577static inline void __sk_del_bind_node(struct sock *sk)
1da177e4
LT
578{
579 __hlist_del(&sk->sk_bind_node);
580}
581
dc6b9b78 582static inline void sk_add_bind_node(struct sock *sk,
1da177e4
LT
583 struct hlist_head *list)
584{
585 hlist_add_head(&sk->sk_bind_node, list);
586}
587
588#define sk_for_each(__sk, node, list) \
589 hlist_for_each_entry(__sk, node, list, sk_node)
808f5114 590#define sk_for_each_rcu(__sk, node, list) \
591 hlist_for_each_entry_rcu(__sk, node, list, sk_node)
88ab1932
ED
592#define sk_nulls_for_each(__sk, node, list) \
593 hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)
594#define sk_nulls_for_each_rcu(__sk, node, list) \
595 hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)
1da177e4
LT
596#define sk_for_each_from(__sk, node) \
597 if (__sk && ({ node = &(__sk)->sk_node; 1; })) \
598 hlist_for_each_entry_from(__sk, node, sk_node)
88ab1932
ED
599#define sk_nulls_for_each_from(__sk, node) \
600 if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \
601 hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node)
1da177e4
LT
602#define sk_for_each_safe(__sk, node, tmp, list) \
603 hlist_for_each_entry_safe(__sk, node, tmp, list, sk_node)
604#define sk_for_each_bound(__sk, node, list) \
605 hlist_for_each_entry(__sk, node, list, sk_bind_node)
606
607/* Sock flags */
608enum sock_flags {
609 SOCK_DEAD,
610 SOCK_DONE,
611 SOCK_URGINLINE,
612 SOCK_KEEPOPEN,
613 SOCK_LINGER,
614 SOCK_DESTROY,
615 SOCK_BROADCAST,
616 SOCK_TIMESTAMP,
617 SOCK_ZAPPED,
618 SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */
619 SOCK_DBG, /* %SO_DEBUG setting */
620 SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
92f37fd2 621 SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */
1da177e4
LT
622 SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
623 SOCK_QUEUE_SHRUNK, /* write queue has been shrunk recently */
20d49473
PO
624 SOCK_TIMESTAMPING_TX_HARDWARE, /* %SOF_TIMESTAMPING_TX_HARDWARE */
625 SOCK_TIMESTAMPING_TX_SOFTWARE, /* %SOF_TIMESTAMPING_TX_SOFTWARE */
626 SOCK_TIMESTAMPING_RX_HARDWARE, /* %SOF_TIMESTAMPING_RX_HARDWARE */
627 SOCK_TIMESTAMPING_RX_SOFTWARE, /* %SOF_TIMESTAMPING_RX_SOFTWARE */
628 SOCK_TIMESTAMPING_SOFTWARE, /* %SOF_TIMESTAMPING_SOFTWARE */
629 SOCK_TIMESTAMPING_RAW_HARDWARE, /* %SOF_TIMESTAMPING_RAW_HARDWARE */
630 SOCK_TIMESTAMPING_SYS_HARDWARE, /* %SOF_TIMESTAMPING_SYS_HARDWARE */
bcdce719 631 SOCK_FASYNC, /* fasync() active */
3b885787 632 SOCK_RXQ_OVFL,
1cdebb42 633 SOCK_ZEROCOPY, /* buffers from userspace */
6e3e939f 634 SOCK_WIFI_STATUS, /* push wifi status to userspace */
3bdc0eba
BG
635 SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS.
636 * Will use last 4 bytes of packet sent from
637 * user-space instead.
638 */
1da177e4
LT
639};
640
53b924b3
RB
641static inline void sock_copy_flags(struct sock *nsk, struct sock *osk)
642{
643 nsk->sk_flags = osk->sk_flags;
644}
645
1da177e4
LT
646static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
647{
648 __set_bit(flag, &sk->sk_flags);
649}
650
651static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag)
652{
653 __clear_bit(flag, &sk->sk_flags);
654}
655
1b23a5df 656static inline bool sock_flag(const struct sock *sk, enum sock_flags flag)
1da177e4
LT
657{
658 return test_bit(flag, &sk->sk_flags);
659}
660
661static inline void sk_acceptq_removed(struct sock *sk)
662{
663 sk->sk_ack_backlog--;
664}
665
666static inline void sk_acceptq_added(struct sock *sk)
667{
668 sk->sk_ack_backlog++;
669}
670
dc6b9b78 671static inline bool sk_acceptq_is_full(const struct sock *sk)
1da177e4 672{
64a14651 673 return sk->sk_ack_backlog > sk->sk_max_ack_backlog;
1da177e4
LT
674}
675
676/*
677 * Compute minimal free write space needed to queue new packets.
678 */
dc6b9b78 679static inline int sk_stream_min_wspace(const struct sock *sk)
1da177e4 680{
8df09ea3 681 return sk->sk_wmem_queued >> 1;
1da177e4
LT
682}
683
dc6b9b78 684static inline int sk_stream_wspace(const struct sock *sk)
1da177e4
LT
685{
686 return sk->sk_sndbuf - sk->sk_wmem_queued;
687}
688
689extern void sk_stream_write_space(struct sock *sk);
690
dc6b9b78 691static inline bool sk_stream_memory_free(const struct sock *sk)
1da177e4
LT
692{
693 return sk->sk_wmem_queued < sk->sk_sndbuf;
694}
695
8eae939f 696/* OOB backlog add */
a3a858ff 697static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
9ee6b535 698{
7fee226a
ED
699 /* dont let skb dst not refcounted, we are going to leave rcu lock */
700 skb_dst_force(skb);
701
702 if (!sk->sk_backlog.tail)
703 sk->sk_backlog.head = skb;
704 else
9ee6b535 705 sk->sk_backlog.tail->next = skb;
7fee226a
ED
706
707 sk->sk_backlog.tail = skb;
9ee6b535
SH
708 skb->next = NULL;
709}
1da177e4 710
c377411f
ED
711/*
712 * Take into account size of receive queue and backlog queue
0fd7bac6
ED
713 * Do not take into account this skb truesize,
714 * to allow even a single big packet to come.
c377411f 715 */
f545a38f
ED
716static inline bool sk_rcvqueues_full(const struct sock *sk, const struct sk_buff *skb,
717 unsigned int limit)
c377411f
ED
718{
719 unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc);
720
f545a38f 721 return qsize > limit;
c377411f
ED
722}
723
8eae939f 724/* The per-socket spinlock must be held here. */
f545a38f
ED
725static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb,
726 unsigned int limit)
8eae939f 727{
f545a38f 728 if (sk_rcvqueues_full(sk, skb, limit))
8eae939f
ZY
729 return -ENOBUFS;
730
a3a858ff 731 __sk_add_backlog(sk, skb);
8eae939f
ZY
732 sk->sk_backlog.len += skb->truesize;
733 return 0;
734}
735
c57943a1
PZ
736static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
737{
738 return sk->sk_backlog_rcv(sk, skb);
739}
740
c58dc01b
DM
741static inline void sock_rps_record_flow(const struct sock *sk)
742{
743#ifdef CONFIG_RPS
744 struct rps_sock_flow_table *sock_flow_table;
745
746 rcu_read_lock();
747 sock_flow_table = rcu_dereference(rps_sock_flow_table);
748 rps_record_sock_flow(sock_flow_table, sk->sk_rxhash);
749 rcu_read_unlock();
750#endif
751}
752
753static inline void sock_rps_reset_flow(const struct sock *sk)
754{
755#ifdef CONFIG_RPS
756 struct rps_sock_flow_table *sock_flow_table;
757
758 rcu_read_lock();
759 sock_flow_table = rcu_dereference(rps_sock_flow_table);
760 rps_reset_sock_flow(sock_flow_table, sk->sk_rxhash);
761 rcu_read_unlock();
762#endif
763}
764
bdeab991
TH
765static inline void sock_rps_save_rxhash(struct sock *sk,
766 const struct sk_buff *skb)
c58dc01b
DM
767{
768#ifdef CONFIG_RPS
bdeab991 769 if (unlikely(sk->sk_rxhash != skb->rxhash)) {
c58dc01b 770 sock_rps_reset_flow(sk);
bdeab991 771 sk->sk_rxhash = skb->rxhash;
c58dc01b
DM
772 }
773#endif
774}
775
bdeab991
TH
776static inline void sock_rps_reset_rxhash(struct sock *sk)
777{
778#ifdef CONFIG_RPS
779 sock_rps_reset_flow(sk);
780 sk->sk_rxhash = 0;
781#endif
782}
783
cfcabdcc
SH
784#define sk_wait_event(__sk, __timeo, __condition) \
785 ({ int __rc; \
786 release_sock(__sk); \
787 __rc = __condition; \
788 if (!__rc) { \
789 *(__timeo) = schedule_timeout(*(__timeo)); \
790 } \
791 lock_sock(__sk); \
792 __rc = __condition; \
793 __rc; \
794 })
1da177e4
LT
795
796extern int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
797extern int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
798extern void sk_stream_wait_close(struct sock *sk, long timeo_p);
799extern int sk_stream_error(struct sock *sk, int flags, int err);
800extern void sk_stream_kill_queues(struct sock *sk);
801
802extern int sk_wait_data(struct sock *sk, long *timeo);
803
60236fdd 804struct request_sock_ops;
6d6ee43e 805struct timewait_sock_ops;
ab1e0a13 806struct inet_hashinfo;
fc8717ba 807struct raw_hashinfo;
de477254 808struct module;
2e6599cb 809
1da177e4
LT
810/* Networking protocol blocks we attach to sockets.
811 * socket layer -> transport layer interface
812 * transport -> network interface is defined by struct inet_proto
813 */
814struct proto {
dc6b9b78 815 void (*close)(struct sock *sk,
1da177e4
LT
816 long timeout);
817 int (*connect)(struct sock *sk,
dc6b9b78 818 struct sockaddr *uaddr,
1da177e4
LT
819 int addr_len);
820 int (*disconnect)(struct sock *sk, int flags);
821
dc6b9b78 822 struct sock * (*accept)(struct sock *sk, int flags, int *err);
1da177e4
LT
823
824 int (*ioctl)(struct sock *sk, int cmd,
825 unsigned long arg);
826 int (*init)(struct sock *sk);
7d06b2e0 827 void (*destroy)(struct sock *sk);
1da177e4 828 void (*shutdown)(struct sock *sk, int how);
dc6b9b78 829 int (*setsockopt)(struct sock *sk, int level,
1da177e4 830 int optname, char __user *optval,
b7058842 831 unsigned int optlen);
dc6b9b78
ED
832 int (*getsockopt)(struct sock *sk, int level,
833 int optname, char __user *optval,
834 int __user *option);
af01d537 835#ifdef CONFIG_COMPAT
3fdadf7d
DM
836 int (*compat_setsockopt)(struct sock *sk,
837 int level,
838 int optname, char __user *optval,
b7058842 839 unsigned int optlen);
3fdadf7d
DM
840 int (*compat_getsockopt)(struct sock *sk,
841 int level,
842 int optname, char __user *optval,
843 int __user *option);
709b46e8
EB
844 int (*compat_ioctl)(struct sock *sk,
845 unsigned int cmd, unsigned long arg);
af01d537 846#endif
1da177e4
LT
847 int (*sendmsg)(struct kiocb *iocb, struct sock *sk,
848 struct msghdr *msg, size_t len);
849 int (*recvmsg)(struct kiocb *iocb, struct sock *sk,
850 struct msghdr *msg,
dc6b9b78
ED
851 size_t len, int noblock, int flags,
852 int *addr_len);
1da177e4
LT
853 int (*sendpage)(struct sock *sk, struct page *page,
854 int offset, size_t size, int flags);
dc6b9b78 855 int (*bind)(struct sock *sk,
1da177e4
LT
856 struct sockaddr *uaddr, int addr_len);
857
dc6b9b78 858 int (*backlog_rcv) (struct sock *sk,
1da177e4
LT
859 struct sk_buff *skb);
860
46d3ceab 861 void (*release_cb)(struct sock *sk);
563d34d0 862 void (*mtu_reduced)(struct sock *sk);
46d3ceab 863
1da177e4
LT
864 /* Keeping track of sk's, looking them up, and port selection methods. */
865 void (*hash)(struct sock *sk);
866 void (*unhash)(struct sock *sk);
719f8358 867 void (*rehash)(struct sock *sk);
1da177e4 868 int (*get_port)(struct sock *sk, unsigned short snum);
fcbdf09d 869 void (*clear_sk)(struct sock *sk, int size);
1da177e4 870
286ab3d4 871 /* Keeping track of sockets in use */
65f76517 872#ifdef CONFIG_PROC_FS
13ff3d6f 873 unsigned int inuse_idx;
65f76517 874#endif
ebb53d75 875
1da177e4 876 /* Memory pressure */
5c52ba17 877 void (*enter_memory_pressure)(struct sock *sk);
8d987e5c 878 atomic_long_t *memory_allocated; /* Current allocated memory. */
1748376b 879 struct percpu_counter *sockets_allocated; /* Current number of sockets. */
1da177e4
LT
880 /*
881 * Pressure flag: try to collapse.
882 * Technical note: it is used by multiple contexts non atomically.
3ab224be 883 * All the __sk_mem_schedule() is of this nature: accounting
1da177e4
LT
884 * is strict, actions are advisory and have some latency.
885 */
886 int *memory_pressure;
8d987e5c 887 long *sysctl_mem;
1da177e4
LT
888 int *sysctl_wmem;
889 int *sysctl_rmem;
890 int max_header;
7ba42910 891 bool no_autobind;
1da177e4 892
271b72c7 893 struct kmem_cache *slab;
1da177e4 894 unsigned int obj_size;
271b72c7 895 int slab_flags;
1da177e4 896
dd24c001 897 struct percpu_counter *orphan_count;
8feaf0c0 898
60236fdd 899 struct request_sock_ops *rsk_prot;
6d6ee43e 900 struct timewait_sock_ops *twsk_prot;
2e6599cb 901
39d8cda7
PE
902 union {
903 struct inet_hashinfo *hashinfo;
645ca708 904 struct udp_table *udp_table;
fc8717ba 905 struct raw_hashinfo *raw_hash;
39d8cda7 906 } h;
ab1e0a13 907
1da177e4
LT
908 struct module *owner;
909
910 char name[32];
911
912 struct list_head node;
e6848976
ACM
913#ifdef SOCK_REFCNT_DEBUG
914 atomic_t socks;
915#endif
c255a458 916#ifdef CONFIG_MEMCG_KMEM
e1aab161
GC
917 /*
918 * cgroup specific init/deinit functions. Called once for all
919 * protocols that implement it, from cgroups populate function.
920 * This function has to setup any files the protocol want to
921 * appear in the kmem cgroup filesystem.
922 */
1d62e436 923 int (*init_cgroup)(struct mem_cgroup *memcg,
e1aab161 924 struct cgroup_subsys *ss);
1d62e436 925 void (*destroy_cgroup)(struct mem_cgroup *memcg);
e1aab161
GC
926 struct cg_proto *(*proto_cgroup)(struct mem_cgroup *memcg);
927#endif
928};
929
3f134619
GC
930/*
931 * Bits in struct cg_proto.flags
932 */
933enum cg_proto_flags {
934 /* Currently active and new sockets should be assigned to cgroups */
935 MEMCG_SOCK_ACTIVE,
936 /* It was ever activated; we must disarm static keys on destruction */
937 MEMCG_SOCK_ACTIVATED,
938};
939
e1aab161
GC
940struct cg_proto {
941 void (*enter_memory_pressure)(struct sock *sk);
942 struct res_counter *memory_allocated; /* Current allocated memory. */
943 struct percpu_counter *sockets_allocated; /* Current number of sockets. */
944 int *memory_pressure;
945 long *sysctl_mem;
3f134619 946 unsigned long flags;
e1aab161
GC
947 /*
948 * memcg field is used to find which memcg we belong directly
949 * Each memcg struct can hold more than one cg_proto, so container_of
950 * won't really cut.
951 *
952 * The elegant solution would be having an inverse function to
953 * proto_cgroup in struct proto, but that means polluting the structure
954 * for everybody, instead of just for memcg users.
955 */
956 struct mem_cgroup *memcg;
1da177e4
LT
957};
958
959extern int proto_register(struct proto *prot, int alloc_slab);
960extern void proto_unregister(struct proto *prot);
961
3f134619
GC
962static inline bool memcg_proto_active(struct cg_proto *cg_proto)
963{
964 return test_bit(MEMCG_SOCK_ACTIVE, &cg_proto->flags);
965}
966
967static inline bool memcg_proto_activated(struct cg_proto *cg_proto)
968{
969 return test_bit(MEMCG_SOCK_ACTIVATED, &cg_proto->flags);
970}
971
e6848976
ACM
972#ifdef SOCK_REFCNT_DEBUG
973static inline void sk_refcnt_debug_inc(struct sock *sk)
974{
975 atomic_inc(&sk->sk_prot->socks);
976}
977
978static inline void sk_refcnt_debug_dec(struct sock *sk)
979{
980 atomic_dec(&sk->sk_prot->socks);
981 printk(KERN_DEBUG "%s socket %p released, %d are still alive\n",
982 sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks));
983}
984
e1aab161 985inline void sk_refcnt_debug_release(const struct sock *sk)
e6848976
ACM
986{
987 if (atomic_read(&sk->sk_refcnt) != 1)
988 printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n",
989 sk->sk_prot->name, sk, atomic_read(&sk->sk_refcnt));
990}
991#else /* SOCK_REFCNT_DEBUG */
992#define sk_refcnt_debug_inc(sk) do { } while (0)
993#define sk_refcnt_debug_dec(sk) do { } while (0)
994#define sk_refcnt_debug_release(sk) do { } while (0)
995#endif /* SOCK_REFCNT_DEBUG */
996
c255a458 997#if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_NET)
c5905afb 998extern struct static_key memcg_socket_limit_enabled;
e1aab161
GC
999static inline struct cg_proto *parent_cg_proto(struct proto *proto,
1000 struct cg_proto *cg_proto)
1001{
1002 return proto->proto_cgroup(parent_mem_cgroup(cg_proto->memcg));
1003}
c5905afb 1004#define mem_cgroup_sockets_enabled static_key_false(&memcg_socket_limit_enabled)
e1aab161
GC
1005#else
1006#define mem_cgroup_sockets_enabled 0
1007static inline struct cg_proto *parent_cg_proto(struct proto *proto,
1008 struct cg_proto *cg_proto)
1009{
1010 return NULL;
1011}
1012#endif
1013
1014
180d8cd9
GC
1015static inline bool sk_has_memory_pressure(const struct sock *sk)
1016{
1017 return sk->sk_prot->memory_pressure != NULL;
1018}
1019
1020static inline bool sk_under_memory_pressure(const struct sock *sk)
1021{
1022 if (!sk->sk_prot->memory_pressure)
1023 return false;
e1aab161
GC
1024
1025 if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1026 return !!*sk->sk_cgrp->memory_pressure;
1027
180d8cd9
GC
1028 return !!*sk->sk_prot->memory_pressure;
1029}
1030
1031static inline void sk_leave_memory_pressure(struct sock *sk)
1032{
1033 int *memory_pressure = sk->sk_prot->memory_pressure;
1034
e1aab161
GC
1035 if (!memory_pressure)
1036 return;
1037
1038 if (*memory_pressure)
180d8cd9 1039 *memory_pressure = 0;
e1aab161
GC
1040
1041 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1042 struct cg_proto *cg_proto = sk->sk_cgrp;
1043 struct proto *prot = sk->sk_prot;
1044
1045 for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto))
1046 if (*cg_proto->memory_pressure)
1047 *cg_proto->memory_pressure = 0;
1048 }
1049
180d8cd9
GC
1050}
1051
1052static inline void sk_enter_memory_pressure(struct sock *sk)
1053{
e1aab161
GC
1054 if (!sk->sk_prot->enter_memory_pressure)
1055 return;
1056
1057 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1058 struct cg_proto *cg_proto = sk->sk_cgrp;
1059 struct proto *prot = sk->sk_prot;
1060
1061 for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto))
1062 cg_proto->enter_memory_pressure(sk);
1063 }
1064
1065 sk->sk_prot->enter_memory_pressure(sk);
180d8cd9
GC
1066}
1067
1068static inline long sk_prot_mem_limits(const struct sock *sk, int index)
1069{
1070 long *prot = sk->sk_prot->sysctl_mem;
e1aab161
GC
1071 if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1072 prot = sk->sk_cgrp->sysctl_mem;
180d8cd9
GC
1073 return prot[index];
1074}
1075
e1aab161
GC
1076static inline void memcg_memory_allocated_add(struct cg_proto *prot,
1077 unsigned long amt,
1078 int *parent_status)
1079{
1080 struct res_counter *fail;
1081 int ret;
1082
0e90b31f
GC
1083 ret = res_counter_charge_nofail(prot->memory_allocated,
1084 amt << PAGE_SHIFT, &fail);
e1aab161
GC
1085 if (ret < 0)
1086 *parent_status = OVER_LIMIT;
1087}
1088
1089static inline void memcg_memory_allocated_sub(struct cg_proto *prot,
1090 unsigned long amt)
1091{
1092 res_counter_uncharge(prot->memory_allocated, amt << PAGE_SHIFT);
1093}
1094
1095static inline u64 memcg_memory_allocated_read(struct cg_proto *prot)
1096{
1097 u64 ret;
1098 ret = res_counter_read_u64(prot->memory_allocated, RES_USAGE);
1099 return ret >> PAGE_SHIFT;
1100}
1101
180d8cd9
GC
1102static inline long
1103sk_memory_allocated(const struct sock *sk)
1104{
1105 struct proto *prot = sk->sk_prot;
e1aab161
GC
1106 if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1107 return memcg_memory_allocated_read(sk->sk_cgrp);
1108
180d8cd9
GC
1109 return atomic_long_read(prot->memory_allocated);
1110}
1111
1112static inline long
e1aab161 1113sk_memory_allocated_add(struct sock *sk, int amt, int *parent_status)
180d8cd9
GC
1114{
1115 struct proto *prot = sk->sk_prot;
e1aab161
GC
1116
1117 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1118 memcg_memory_allocated_add(sk->sk_cgrp, amt, parent_status);
1119 /* update the root cgroup regardless */
1120 atomic_long_add_return(amt, prot->memory_allocated);
1121 return memcg_memory_allocated_read(sk->sk_cgrp);
1122 }
1123
180d8cd9
GC
1124 return atomic_long_add_return(amt, prot->memory_allocated);
1125}
1126
1127static inline void
0e90b31f 1128sk_memory_allocated_sub(struct sock *sk, int amt)
180d8cd9
GC
1129{
1130 struct proto *prot = sk->sk_prot;
e1aab161 1131
0e90b31f 1132 if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
e1aab161
GC
1133 memcg_memory_allocated_sub(sk->sk_cgrp, amt);
1134
180d8cd9
GC
1135 atomic_long_sub(amt, prot->memory_allocated);
1136}
1137
1138static inline void sk_sockets_allocated_dec(struct sock *sk)
1139{
1140 struct proto *prot = sk->sk_prot;
e1aab161
GC
1141
1142 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1143 struct cg_proto *cg_proto = sk->sk_cgrp;
1144
1145 for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto))
1146 percpu_counter_dec(cg_proto->sockets_allocated);
1147 }
1148
180d8cd9
GC
1149 percpu_counter_dec(prot->sockets_allocated);
1150}
1151
1152static inline void sk_sockets_allocated_inc(struct sock *sk)
1153{
1154 struct proto *prot = sk->sk_prot;
e1aab161
GC
1155
1156 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1157 struct cg_proto *cg_proto = sk->sk_cgrp;
1158
1159 for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto))
1160 percpu_counter_inc(cg_proto->sockets_allocated);
1161 }
1162
180d8cd9
GC
1163 percpu_counter_inc(prot->sockets_allocated);
1164}
1165
1166static inline int
1167sk_sockets_allocated_read_positive(struct sock *sk)
1168{
1169 struct proto *prot = sk->sk_prot;
1170
e1aab161 1171 if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
518fbf9c 1172 return percpu_counter_read_positive(sk->sk_cgrp->sockets_allocated);
e1aab161 1173
518fbf9c 1174 return percpu_counter_read_positive(prot->sockets_allocated);
180d8cd9
GC
1175}
1176
1177static inline int
1178proto_sockets_allocated_sum_positive(struct proto *prot)
1179{
1180 return percpu_counter_sum_positive(prot->sockets_allocated);
1181}
1182
1183static inline long
1184proto_memory_allocated(struct proto *prot)
1185{
1186 return atomic_long_read(prot->memory_allocated);
1187}
1188
1189static inline bool
1190proto_memory_pressure(struct proto *prot)
1191{
1192 if (!prot->memory_pressure)
1193 return false;
1194 return !!*prot->memory_pressure;
1195}
1196
65f76517
ED
1197
1198#ifdef CONFIG_PROC_FS
1da177e4 1199/* Called with local bh disabled */
c29a0bc4
PE
1200extern void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc);
1201extern int sock_prot_inuse_get(struct net *net, struct proto *proto);
65f76517 1202#else
dc6b9b78 1203static inline void sock_prot_inuse_add(struct net *net, struct proto *prot,
c29a0bc4 1204 int inc)
65f76517
ED
1205{
1206}
65f76517
ED
1207#endif
1208
1da177e4 1209
614c6cb4
ACM
1210/* With per-bucket locks this operation is not-atomic, so that
1211 * this version is not worse.
1212 */
1213static inline void __sk_prot_rehash(struct sock *sk)
1214{
1215 sk->sk_prot->unhash(sk);
1216 sk->sk_prot->hash(sk);
1217}
1218
fcbdf09d
OP
1219void sk_prot_clear_portaddr_nulls(struct sock *sk, int size);
1220
1da177e4
LT
1221/* About 10 seconds */
1222#define SOCK_DESTROY_TIME (10*HZ)
1223
1224/* Sockets 0-1023 can't be bound to unless you are superuser */
1225#define PROT_SOCK 1024
1226
1227#define SHUTDOWN_MASK 3
1228#define RCV_SHUTDOWN 1
1229#define SEND_SHUTDOWN 2
1230
1231#define SOCK_SNDBUF_LOCK 1
1232#define SOCK_RCVBUF_LOCK 2
1233#define SOCK_BINDADDR_LOCK 4
1234#define SOCK_BINDPORT_LOCK 8
1235
1236/* sock_iocb: used to kick off async processing of socket ios */
1237struct sock_iocb {
1238 struct list_head list;
1239
1240 int flags;
1241 int size;
1242 struct socket *sock;
1243 struct sock *sk;
1244 struct scm_cookie *scm;
1245 struct msghdr *msg, async_msg;
1da177e4
LT
1246 struct kiocb *kiocb;
1247};
1248
1249static inline struct sock_iocb *kiocb_to_siocb(struct kiocb *iocb)
1250{
1251 return (struct sock_iocb *)iocb->private;
1252}
1253
1254static inline struct kiocb *siocb_to_kiocb(struct sock_iocb *si)
1255{
1256 return si->kiocb;
1257}
1258
1259struct socket_alloc {
1260 struct socket socket;
1261 struct inode vfs_inode;
1262};
1263
1264static inline struct socket *SOCKET_I(struct inode *inode)
1265{
1266 return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
1267}
1268
1269static inline struct inode *SOCK_INODE(struct socket *socket)
1270{
1271 return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
1272}
1273
3ab224be
HA
1274/*
1275 * Functions for memory accounting
1276 */
1277extern int __sk_mem_schedule(struct sock *sk, int size, int kind);
1278extern void __sk_mem_reclaim(struct sock *sk);
1da177e4 1279
3ab224be
HA
1280#define SK_MEM_QUANTUM ((int)PAGE_SIZE)
1281#define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM)
1282#define SK_MEM_SEND 0
1283#define SK_MEM_RECV 1
1da177e4 1284
3ab224be 1285static inline int sk_mem_pages(int amt)
1da177e4 1286{
3ab224be 1287 return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT;
1da177e4
LT
1288}
1289
dc6b9b78 1290static inline bool sk_has_account(struct sock *sk)
1da177e4 1291{
3ab224be
HA
1292 /* return true if protocol supports memory accounting */
1293 return !!sk->sk_prot->memory_allocated;
1da177e4
LT
1294}
1295
dc6b9b78 1296static inline bool sk_wmem_schedule(struct sock *sk, int size)
1da177e4 1297{
3ab224be 1298 if (!sk_has_account(sk))
dc6b9b78 1299 return true;
3ab224be
HA
1300 return size <= sk->sk_forward_alloc ||
1301 __sk_mem_schedule(sk, size, SK_MEM_SEND);
1da177e4
LT
1302}
1303
dc6b9b78 1304static inline bool sk_rmem_schedule(struct sock *sk, int size)
d80d99d6 1305{
3ab224be 1306 if (!sk_has_account(sk))
dc6b9b78 1307 return true;
d80d99d6 1308 return size <= sk->sk_forward_alloc ||
3ab224be
HA
1309 __sk_mem_schedule(sk, size, SK_MEM_RECV);
1310}
1311
1312static inline void sk_mem_reclaim(struct sock *sk)
1313{
1314 if (!sk_has_account(sk))
1315 return;
1316 if (sk->sk_forward_alloc >= SK_MEM_QUANTUM)
1317 __sk_mem_reclaim(sk);
1318}
1319
9993e7d3
DM
1320static inline void sk_mem_reclaim_partial(struct sock *sk)
1321{
1322 if (!sk_has_account(sk))
1323 return;
1324 if (sk->sk_forward_alloc > SK_MEM_QUANTUM)
1325 __sk_mem_reclaim(sk);
1326}
1327
3ab224be
HA
1328static inline void sk_mem_charge(struct sock *sk, int size)
1329{
1330 if (!sk_has_account(sk))
1331 return;
1332 sk->sk_forward_alloc -= size;
1333}
1334
1335static inline void sk_mem_uncharge(struct sock *sk, int size)
1336{
1337 if (!sk_has_account(sk))
1338 return;
1339 sk->sk_forward_alloc += size;
1340}
1341
1342static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb)
1343{
3ab224be
HA
1344 sock_set_flag(sk, SOCK_QUEUE_SHRUNK);
1345 sk->sk_wmem_queued -= skb->truesize;
1346 sk_mem_uncharge(sk, skb->truesize);
1347 __kfree_skb(skb);
d80d99d6
HX
1348}
1349
1da177e4
LT
1350/* Used by processes to "lock" a socket state, so that
1351 * interrupts and bottom half handlers won't change it
1352 * from under us. It essentially blocks any incoming
1353 * packets, so that we won't get any new data or any
1354 * packets that change the state of the socket.
1355 *
1356 * While locked, BH processing will add new packets to
1357 * the backlog queue. This queue is processed by the
1358 * owner of the socket lock right before it is released.
1359 *
1360 * Since ~2.3.5 it is also exclusive sleep lock serializing
1361 * accesses from user process context.
1362 */
d2e9117c 1363#define sock_owned_by_user(sk) ((sk)->sk_lock.owned)
1da177e4 1364
ed07536e
PZ
1365/*
1366 * Macro so as to not evaluate some arguments when
1367 * lockdep is not enabled.
1368 *
1369 * Mark both the sk_lock and the sk_lock.slock as a
1370 * per-address-family lock class.
1371 */
dc6b9b78 1372#define sock_lock_init_class_and_name(sk, sname, skey, name, key) \
ed07536e 1373do { \
e8f6fbf6 1374 sk->sk_lock.owned = 0; \
ed07536e
PZ
1375 init_waitqueue_head(&sk->sk_lock.wq); \
1376 spin_lock_init(&(sk)->sk_lock.slock); \
1377 debug_check_no_locks_freed((void *)&(sk)->sk_lock, \
1378 sizeof((sk)->sk_lock)); \
1379 lockdep_set_class_and_name(&(sk)->sk_lock.slock, \
dc6b9b78 1380 (skey), (sname)); \
ed07536e
PZ
1381 lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \
1382} while (0)
1383
41380930 1384extern void lock_sock_nested(struct sock *sk, int subclass);
fcc70d5f
PZ
1385
1386static inline void lock_sock(struct sock *sk)
1387{
1388 lock_sock_nested(sk, 0);
1389}
1390
41380930 1391extern void release_sock(struct sock *sk);
1da177e4
LT
1392
1393/* BH context may only use the following locking interface. */
1394#define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock))
c6366184
IM
1395#define bh_lock_sock_nested(__sk) \
1396 spin_lock_nested(&((__sk)->sk_lock.slock), \
1397 SINGLE_DEPTH_NESTING)
1da177e4
LT
1398#define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock))
1399
8a74ad60
ED
1400extern bool lock_sock_fast(struct sock *sk);
1401/**
1402 * unlock_sock_fast - complement of lock_sock_fast
1403 * @sk: socket
1404 * @slow: slow mode
1405 *
1406 * fast unlock socket for user context.
1407 * If slow mode is on, we call regular release_sock()
1408 */
1409static inline void unlock_sock_fast(struct sock *sk, bool slow)
4b0b72f7 1410{
8a74ad60
ED
1411 if (slow)
1412 release_sock(sk);
1413 else
1414 spin_unlock_bh(&sk->sk_lock.slock);
4b0b72f7
ED
1415}
1416
4b0b72f7 1417
1b8d7ae4 1418extern struct sock *sk_alloc(struct net *net, int family,
dd0fc66f 1419 gfp_t priority,
6257ff21 1420 struct proto *prot);
1da177e4 1421extern void sk_free(struct sock *sk);
edf02087 1422extern void sk_release_kernel(struct sock *sk);
e56c57d0
ED
1423extern struct sock *sk_clone_lock(const struct sock *sk,
1424 const gfp_t priority);
1da177e4
LT
1425
1426extern struct sk_buff *sock_wmalloc(struct sock *sk,
1427 unsigned long size, int force,
dd0fc66f 1428 gfp_t priority);
1da177e4
LT
1429extern struct sk_buff *sock_rmalloc(struct sock *sk,
1430 unsigned long size, int force,
dd0fc66f 1431 gfp_t priority);
1da177e4
LT
1432extern void sock_wfree(struct sk_buff *skb);
1433extern void sock_rfree(struct sk_buff *skb);
41063e9d 1434extern void sock_edemux(struct sk_buff *skb);
1da177e4
LT
1435
1436extern int sock_setsockopt(struct socket *sock, int level,
1437 int op, char __user *optval,
b7058842 1438 unsigned int optlen);
1da177e4
LT
1439
1440extern int sock_getsockopt(struct socket *sock, int level,
dc6b9b78 1441 int op, char __user *optval,
1da177e4 1442 int __user *optlen);
dc6b9b78 1443extern struct sk_buff *sock_alloc_send_skb(struct sock *sk,
1da177e4
LT
1444 unsigned long size,
1445 int noblock,
1446 int *errcode);
dc6b9b78 1447extern struct sk_buff *sock_alloc_send_pskb(struct sock *sk,
4cc7f68d
HX
1448 unsigned long header_len,
1449 unsigned long data_len,
1450 int noblock,
1451 int *errcode);
86a76caf 1452extern void *sock_kmalloc(struct sock *sk, int size,
dd0fc66f 1453 gfp_t priority);
1da177e4
LT
1454extern void sock_kfree_s(struct sock *sk, void *mem, int size);
1455extern void sk_send_sigurg(struct sock *sk);
1456
f8451725
HX
1457#ifdef CONFIG_CGROUPS
1458extern void sock_update_classid(struct sock *sk);
1459#else
1460static inline void sock_update_classid(struct sock *sk)
1461{
1462}
1463#endif
1464
1da177e4
LT
1465/*
1466 * Functions to fill in entries in struct proto_ops when a protocol
1467 * does not implement a particular function.
1468 */
dc6b9b78 1469extern int sock_no_bind(struct socket *,
1da177e4
LT
1470 struct sockaddr *, int);
1471extern int sock_no_connect(struct socket *,
1472 struct sockaddr *, int, int);
1473extern int sock_no_socketpair(struct socket *,
1474 struct socket *);
1475extern int sock_no_accept(struct socket *,
1476 struct socket *, int);
1477extern int sock_no_getname(struct socket *,
1478 struct sockaddr *, int *, int);
1479extern unsigned int sock_no_poll(struct file *, struct socket *,
1480 struct poll_table_struct *);
1481extern int sock_no_ioctl(struct socket *, unsigned int,
1482 unsigned long);
1483extern int sock_no_listen(struct socket *, int);
1484extern int sock_no_shutdown(struct socket *, int);
1485extern int sock_no_getsockopt(struct socket *, int , int,
1486 char __user *, int __user *);
1487extern int sock_no_setsockopt(struct socket *, int, int,
b7058842 1488 char __user *, unsigned int);
1da177e4
LT
1489extern int sock_no_sendmsg(struct kiocb *, struct socket *,
1490 struct msghdr *, size_t);
1491extern int sock_no_recvmsg(struct kiocb *, struct socket *,
1492 struct msghdr *, size_t, int);
1493extern int sock_no_mmap(struct file *file,
1494 struct socket *sock,
1495 struct vm_area_struct *vma);
1496extern ssize_t sock_no_sendpage(struct socket *sock,
1497 struct page *page,
dc6b9b78 1498 int offset, size_t size,
1da177e4
LT
1499 int flags);
1500
1501/*
1502 * Functions to fill in entries in struct proto_ops when a protocol
1503 * uses the inet style.
1504 */
1505extern int sock_common_getsockopt(struct socket *sock, int level, int optname,
1506 char __user *optval, int __user *optlen);
1507extern int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock,
1508 struct msghdr *msg, size_t size, int flags);
1509extern int sock_common_setsockopt(struct socket *sock, int level, int optname,
b7058842 1510 char __user *optval, unsigned int optlen);
3fdadf7d
DM
1511extern int compat_sock_common_getsockopt(struct socket *sock, int level,
1512 int optname, char __user *optval, int __user *optlen);
1513extern int compat_sock_common_setsockopt(struct socket *sock, int level,
b7058842 1514 int optname, char __user *optval, unsigned int optlen);
1da177e4
LT
1515
1516extern void sk_common_release(struct sock *sk);
1517
1518/*
1519 * Default socket callbacks and setup code
1520 */
dc6b9b78 1521
1da177e4
LT
1522/* Initialise core socket variables */
1523extern void sock_init_data(struct socket *sock, struct sock *sk);
1524
46bcf14f
ED
1525extern void sk_filter_release_rcu(struct rcu_head *rcu);
1526
dc9b3346 1527/**
1a5778aa 1528 * sk_filter_release - release a socket filter
dc9b3346
PB
1529 * @fp: filter to remove
1530 *
1531 * Remove a filter from a socket and release its resources.
1532 */
1533
309dd5fc
PE
1534static inline void sk_filter_release(struct sk_filter *fp)
1535{
1536 if (atomic_dec_and_test(&fp->refcnt))
80f8f102 1537 call_rcu(&fp->rcu, sk_filter_release_rcu);
309dd5fc
PE
1538}
1539
1540static inline void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp)
1da177e4
LT
1541{
1542 unsigned int size = sk_filter_len(fp);
1543
1544 atomic_sub(size, &sk->sk_omem_alloc);
309dd5fc 1545 sk_filter_release(fp);
1da177e4
LT
1546}
1547
1548static inline void sk_filter_charge(struct sock *sk, struct sk_filter *fp)
1549{
1550 atomic_inc(&fp->refcnt);
1551 atomic_add(sk_filter_len(fp), &sk->sk_omem_alloc);
1552}
1553
1554/*
1555 * Socket reference counting postulates.
1556 *
1557 * * Each user of socket SHOULD hold a reference count.
1558 * * Each access point to socket (an hash table bucket, reference from a list,
1559 * running timer, skb in flight MUST hold a reference count.
1560 * * When reference count hits 0, it means it will never increase back.
1561 * * When reference count hits 0, it means that no references from
1562 * outside exist to this socket and current process on current CPU
1563 * is last user and may/should destroy this socket.
1564 * * sk_free is called from any context: process, BH, IRQ. When
1565 * it is called, socket has no references from outside -> sk_free
1566 * may release descendant resources allocated by the socket, but
1567 * to the time when it is called, socket is NOT referenced by any
1568 * hash tables, lists etc.
1569 * * Packets, delivered from outside (from network or from another process)
1570 * and enqueued on receive/error queues SHOULD NOT grab reference count,
1571 * when they sit in queue. Otherwise, packets will leak to hole, when
1572 * socket is looked up by one cpu and unhasing is made by another CPU.
1573 * It is true for udp/raw, netlink (leak to receive and error queues), tcp
1574 * (leak to backlog). Packet socket does all the processing inside
1575 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
1576 * use separate SMP lock, so that they are prone too.
1577 */
1578
1579/* Ungrab socket and destroy it, if it was the last reference. */
1580static inline void sock_put(struct sock *sk)
1581{
1582 if (atomic_dec_and_test(&sk->sk_refcnt))
1583 sk_free(sk);
1584}
1585
58a5a7b9
ACM
1586extern int sk_receive_skb(struct sock *sk, struct sk_buff *skb,
1587 const int nested);
25995ff5 1588
e022f0b4
KK
1589static inline void sk_tx_queue_set(struct sock *sk, int tx_queue)
1590{
1591 sk->sk_tx_queue_mapping = tx_queue;
1592}
1593
1594static inline void sk_tx_queue_clear(struct sock *sk)
1595{
1596 sk->sk_tx_queue_mapping = -1;
1597}
1598
1599static inline int sk_tx_queue_get(const struct sock *sk)
1600{
b0f77d0e 1601 return sk ? sk->sk_tx_queue_mapping : -1;
e022f0b4
KK
1602}
1603
972692e0
DM
1604static inline void sk_set_socket(struct sock *sk, struct socket *sock)
1605{
e022f0b4 1606 sk_tx_queue_clear(sk);
972692e0
DM
1607 sk->sk_socket = sock;
1608}
1609
aa395145
ED
1610static inline wait_queue_head_t *sk_sleep(struct sock *sk)
1611{
eaefd110
ED
1612 BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0);
1613 return &rcu_dereference_raw(sk->sk_wq)->wait;
aa395145 1614}
1da177e4
LT
1615/* Detach socket from process context.
1616 * Announce socket dead, detach it from wait queue and inode.
1617 * Note that parent inode held reference count on this struct sock,
1618 * we do not release it in this function, because protocol
1619 * probably wants some additional cleanups or even continuing
1620 * to work with this socket (TCP).
1621 */
1622static inline void sock_orphan(struct sock *sk)
1623{
1624 write_lock_bh(&sk->sk_callback_lock);
1625 sock_set_flag(sk, SOCK_DEAD);
972692e0 1626 sk_set_socket(sk, NULL);
43815482 1627 sk->sk_wq = NULL;
1da177e4
LT
1628 write_unlock_bh(&sk->sk_callback_lock);
1629}
1630
1631static inline void sock_graft(struct sock *sk, struct socket *parent)
1632{
1633 write_lock_bh(&sk->sk_callback_lock);
eaefd110 1634 sk->sk_wq = parent->wq;
1da177e4 1635 parent->sk = sk;
972692e0 1636 sk_set_socket(sk, parent);
4237c75c 1637 security_sock_graft(sk, parent);
1da177e4
LT
1638 write_unlock_bh(&sk->sk_callback_lock);
1639}
1640
1641extern int sock_i_uid(struct sock *sk);
1642extern unsigned long sock_i_ino(struct sock *sk);
1643
1644static inline struct dst_entry *
1645__sk_dst_get(struct sock *sk)
1646{
d8bf4ca9 1647 return rcu_dereference_check(sk->sk_dst_cache, sock_owned_by_user(sk) ||
f68c224f 1648 lockdep_is_held(&sk->sk_lock.slock));
1da177e4
LT
1649}
1650
1651static inline struct dst_entry *
1652sk_dst_get(struct sock *sk)
1653{
1654 struct dst_entry *dst;
1655
b6c6712a
ED
1656 rcu_read_lock();
1657 dst = rcu_dereference(sk->sk_dst_cache);
1da177e4
LT
1658 if (dst)
1659 dst_hold(dst);
b6c6712a 1660 rcu_read_unlock();
1da177e4
LT
1661 return dst;
1662}
1663
b6c6712a
ED
1664extern void sk_reset_txq(struct sock *sk);
1665
1666static inline void dst_negative_advice(struct sock *sk)
1667{
1668 struct dst_entry *ndst, *dst = __sk_dst_get(sk);
1669
1670 if (dst && dst->ops->negative_advice) {
1671 ndst = dst->ops->negative_advice(dst);
1672
1673 if (ndst != dst) {
1674 rcu_assign_pointer(sk->sk_dst_cache, ndst);
1675 sk_reset_txq(sk);
1676 }
1677 }
1678}
1679
1da177e4
LT
1680static inline void
1681__sk_dst_set(struct sock *sk, struct dst_entry *dst)
1682{
1683 struct dst_entry *old_dst;
1684
e022f0b4 1685 sk_tx_queue_clear(sk);
0b53ff2e
ED
1686 /*
1687 * This can be called while sk is owned by the caller only,
1688 * with no state that can be checked in a rcu_dereference_check() cond
1689 */
1690 old_dst = rcu_dereference_raw(sk->sk_dst_cache);
b6c6712a 1691 rcu_assign_pointer(sk->sk_dst_cache, dst);
1da177e4
LT
1692 dst_release(old_dst);
1693}
1694
1695static inline void
1696sk_dst_set(struct sock *sk, struct dst_entry *dst)
1697{
b6c6712a 1698 spin_lock(&sk->sk_dst_lock);
1da177e4 1699 __sk_dst_set(sk, dst);
b6c6712a 1700 spin_unlock(&sk->sk_dst_lock);
1da177e4
LT
1701}
1702
1703static inline void
1704__sk_dst_reset(struct sock *sk)
1705{
b6c6712a 1706 __sk_dst_set(sk, NULL);
1da177e4
LT
1707}
1708
1709static inline void
1710sk_dst_reset(struct sock *sk)
1711{
b6c6712a 1712 spin_lock(&sk->sk_dst_lock);
1da177e4 1713 __sk_dst_reset(sk);
b6c6712a 1714 spin_unlock(&sk->sk_dst_lock);
1da177e4
LT
1715}
1716
f0088a50 1717extern struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
1da177e4 1718
f0088a50 1719extern struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
1da177e4 1720
dc6b9b78 1721static inline bool sk_can_gso(const struct sock *sk)
bcd76111
HX
1722{
1723 return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type);
1724}
1725
9958089a 1726extern void sk_setup_caps(struct sock *sk, struct dst_entry *dst);
6cbb0df7 1727
c8f44aff 1728static inline void sk_nocaps_add(struct sock *sk, netdev_features_t flags)
a465419b
ED
1729{
1730 sk->sk_route_nocaps |= flags;
1731 sk->sk_route_caps &= ~flags;
1732}
1733
c6e1a0d1
TH
1734static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
1735 char __user *from, char *to,
912d398d 1736 int copy, int offset)
c6e1a0d1
TH
1737{
1738 if (skb->ip_summed == CHECKSUM_NONE) {
1739 int err = 0;
1740 __wsum csum = csum_and_copy_from_user(from, to, copy, 0, &err);
1741 if (err)
1742 return err;
912d398d 1743 skb->csum = csum_block_add(skb->csum, csum, offset);
c6e1a0d1
TH
1744 } else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
1745 if (!access_ok(VERIFY_READ, from, copy) ||
1746 __copy_from_user_nocache(to, from, copy))
1747 return -EFAULT;
1748 } else if (copy_from_user(to, from, copy))
1749 return -EFAULT;
1750
1751 return 0;
1752}
1753
1754static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
1755 char __user *from, int copy)
1756{
912d398d 1757 int err, offset = skb->len;
c6e1a0d1 1758
912d398d
WY
1759 err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy),
1760 copy, offset);
c6e1a0d1 1761 if (err)
912d398d 1762 __skb_trim(skb, offset);
c6e1a0d1
TH
1763
1764 return err;
1765}
1766
1767static inline int skb_copy_to_page_nocache(struct sock *sk, char __user *from,
1768 struct sk_buff *skb,
1769 struct page *page,
1770 int off, int copy)
1771{
1772 int err;
1773
912d398d
WY
1774 err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off,
1775 copy, skb->len);
c6e1a0d1
TH
1776 if (err)
1777 return err;
1778
1779 skb->len += copy;
1780 skb->data_len += copy;
1781 skb->truesize += copy;
1782 sk->sk_wmem_queued += copy;
1783 sk_mem_charge(sk, copy);
1784 return 0;
1785}
1786
1da177e4
LT
1787static inline int skb_copy_to_page(struct sock *sk, char __user *from,
1788 struct sk_buff *skb, struct page *page,
1789 int off, int copy)
1790{
1791 if (skb->ip_summed == CHECKSUM_NONE) {
1792 int err = 0;
5084205f 1793 __wsum csum = csum_and_copy_from_user(from,
1da177e4
LT
1794 page_address(page) + off,
1795 copy, 0, &err);
1796 if (err)
1797 return err;
1798 skb->csum = csum_block_add(skb->csum, csum, skb->len);
1799 } else if (copy_from_user(page_address(page) + off, from, copy))
1800 return -EFAULT;
1801
1802 skb->len += copy;
1803 skb->data_len += copy;
1804 skb->truesize += copy;
1805 sk->sk_wmem_queued += copy;
3ab224be 1806 sk_mem_charge(sk, copy);
1da177e4
LT
1807 return 0;
1808}
1809
c564039f
ED
1810/**
1811 * sk_wmem_alloc_get - returns write allocations
1812 * @sk: socket
1813 *
1814 * Returns sk_wmem_alloc minus initial offset of one
1815 */
1816static inline int sk_wmem_alloc_get(const struct sock *sk)
1817{
1818 return atomic_read(&sk->sk_wmem_alloc) - 1;
1819}
1820
1821/**
1822 * sk_rmem_alloc_get - returns read allocations
1823 * @sk: socket
1824 *
1825 * Returns sk_rmem_alloc
1826 */
1827static inline int sk_rmem_alloc_get(const struct sock *sk)
1828{
1829 return atomic_read(&sk->sk_rmem_alloc);
1830}
1831
1832/**
1833 * sk_has_allocations - check if allocations are outstanding
1834 * @sk: socket
1835 *
1836 * Returns true if socket has write or read allocations
1837 */
dc6b9b78 1838static inline bool sk_has_allocations(const struct sock *sk)
c564039f
ED
1839{
1840 return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk);
1841}
1842
a57de0b4 1843/**
43815482 1844 * wq_has_sleeper - check if there are any waiting processes
acfbe96a 1845 * @wq: struct socket_wq
a57de0b4 1846 *
43815482 1847 * Returns true if socket_wq has waiting processes
a57de0b4 1848 *
43815482 1849 * The purpose of the wq_has_sleeper and sock_poll_wait is to wrap the memory
a57de0b4
JO
1850 * barrier call. They were added due to the race found within the tcp code.
1851 *
1852 * Consider following tcp code paths:
1853 *
1854 * CPU1 CPU2
1855 *
1856 * sys_select receive packet
1857 * ... ...
1858 * __add_wait_queue update tp->rcv_nxt
1859 * ... ...
1860 * tp->rcv_nxt check sock_def_readable
1861 * ... {
43815482
ED
1862 * schedule rcu_read_lock();
1863 * wq = rcu_dereference(sk->sk_wq);
1864 * if (wq && waitqueue_active(&wq->wait))
1865 * wake_up_interruptible(&wq->wait)
a57de0b4
JO
1866 * ...
1867 * }
1868 *
1869 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
1870 * in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1
1871 * could then endup calling schedule and sleep forever if there are no more
1872 * data on the socket.
ad462769 1873 *
a57de0b4 1874 */
43815482 1875static inline bool wq_has_sleeper(struct socket_wq *wq)
a57de0b4 1876{
dc6b9b78 1877 /* We need to be sure we are in sync with the
a57de0b4
JO
1878 * add_wait_queue modifications to the wait queue.
1879 *
1880 * This memory barrier is paired in the sock_poll_wait.
1881 */
43815482
ED
1882 smp_mb();
1883 return wq && waitqueue_active(&wq->wait);
a57de0b4
JO
1884}
1885
1886/**
1887 * sock_poll_wait - place memory barrier behind the poll_wait call.
1888 * @filp: file
1889 * @wait_address: socket wait queue
1890 * @p: poll_table
1891 *
43815482 1892 * See the comments in the wq_has_sleeper function.
a57de0b4
JO
1893 */
1894static inline void sock_poll_wait(struct file *filp,
1895 wait_queue_head_t *wait_address, poll_table *p)
1896{
626cf236 1897 if (!poll_does_not_wait(p) && wait_address) {
a57de0b4 1898 poll_wait(filp, wait_address, p);
dc6b9b78 1899 /* We need to be sure we are in sync with the
a57de0b4
JO
1900 * socket flags modification.
1901 *
43815482 1902 * This memory barrier is paired in the wq_has_sleeper.
dc6b9b78 1903 */
a57de0b4
JO
1904 smp_mb();
1905 }
1906}
1907
1da177e4 1908/*
dc6b9b78 1909 * Queue a received datagram if it will fit. Stream and sequenced
1da177e4
LT
1910 * protocols can't normally use this as they need to fit buffers in
1911 * and play with them.
1912 *
dc6b9b78 1913 * Inlined as it's very short and called for pretty much every
1da177e4
LT
1914 * packet ever received.
1915 */
1916
1917static inline void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
1918{
d55d87fd 1919 skb_orphan(skb);
1da177e4
LT
1920 skb->sk = sk;
1921 skb->destructor = sock_wfree;
2b85a34e
ED
1922 /*
1923 * We used to take a refcount on sk, but following operation
1924 * is enough to guarantee sk_free() wont free this sock until
1925 * all in-flight packets are completed
1926 */
1da177e4
LT
1927 atomic_add(skb->truesize, &sk->sk_wmem_alloc);
1928}
1929
1930static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
1931{
d55d87fd 1932 skb_orphan(skb);
1da177e4
LT
1933 skb->sk = sk;
1934 skb->destructor = sock_rfree;
1935 atomic_add(skb->truesize, &sk->sk_rmem_alloc);
3ab224be 1936 sk_mem_charge(sk, skb->truesize);
1da177e4
LT
1937}
1938
dc6b9b78 1939extern void sk_reset_timer(struct sock *sk, struct timer_list *timer,
1da177e4
LT
1940 unsigned long expires);
1941
dc6b9b78 1942extern void sk_stop_timer(struct sock *sk, struct timer_list *timer);
1da177e4 1943
f0088a50 1944extern int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
1da177e4 1945
b1faf566 1946extern int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
1da177e4
LT
1947
1948/*
1949 * Recover an error report and clear atomically
1950 */
dc6b9b78 1951
1da177e4
LT
1952static inline int sock_error(struct sock *sk)
1953{
c1cbe4b7
BL
1954 int err;
1955 if (likely(!sk->sk_err))
1956 return 0;
1957 err = xchg(&sk->sk_err, 0);
1da177e4
LT
1958 return -err;
1959}
1960
1961static inline unsigned long sock_wspace(struct sock *sk)
1962{
1963 int amt = 0;
1964
1965 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
1966 amt = sk->sk_sndbuf - atomic_read(&sk->sk_wmem_alloc);
dc6b9b78 1967 if (amt < 0)
1da177e4
LT
1968 amt = 0;
1969 }
1970 return amt;
1971}
1972
1973static inline void sk_wake_async(struct sock *sk, int how, int band)
1974{
bcdce719 1975 if (sock_flag(sk, SOCK_FASYNC))
1da177e4
LT
1976 sock_wake_async(sk->sk_socket, how, band);
1977}
1978
1979#define SOCK_MIN_SNDBUF 2048
7a91b434
ED
1980/*
1981 * Since sk_rmem_alloc sums skb->truesize, even a small frame might need
1982 * sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak
1983 */
1984#define SOCK_MIN_RCVBUF (2048 + sizeof(struct sk_buff))
1da177e4
LT
1985
1986static inline void sk_stream_moderate_sndbuf(struct sock *sk)
1987{
1988 if (!(sk->sk_userlocks & SOCK_SNDBUF_LOCK)) {
8df09ea3 1989 sk->sk_sndbuf = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
1da177e4
LT
1990 sk->sk_sndbuf = max(sk->sk_sndbuf, SOCK_MIN_SNDBUF);
1991 }
1992}
1993
df97c708 1994struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp);
1da177e4
LT
1995
1996static inline struct page *sk_stream_alloc_page(struct sock *sk)
1997{
1998 struct page *page = NULL;
1999
ef015786
HX
2000 page = alloc_pages(sk->sk_allocation, 0);
2001 if (!page) {
180d8cd9 2002 sk_enter_memory_pressure(sk);
1da177e4
LT
2003 sk_stream_moderate_sndbuf(sk);
2004 }
2005 return page;
2006}
2007
1da177e4
LT
2008/*
2009 * Default write policy as shown to user space via poll/select/SIGIO
2010 */
dc6b9b78 2011static inline bool sock_writeable(const struct sock *sk)
1da177e4 2012{
8df09ea3 2013 return atomic_read(&sk->sk_wmem_alloc) < (sk->sk_sndbuf >> 1);
1da177e4
LT
2014}
2015
dd0fc66f 2016static inline gfp_t gfp_any(void)
1da177e4 2017{
99709372 2018 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
1da177e4
LT
2019}
2020
dc6b9b78 2021static inline long sock_rcvtimeo(const struct sock *sk, bool noblock)
1da177e4
LT
2022{
2023 return noblock ? 0 : sk->sk_rcvtimeo;
2024}
2025
dc6b9b78 2026static inline long sock_sndtimeo(const struct sock *sk, bool noblock)
1da177e4
LT
2027{
2028 return noblock ? 0 : sk->sk_sndtimeo;
2029}
2030
2031static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
2032{
2033 return (waitall ? len : min_t(int, sk->sk_rcvlowat, len)) ? : 1;
2034}
2035
2036/* Alas, with timeout socket operations are not restartable.
2037 * Compare this to poll().
2038 */
2039static inline int sock_intr_errno(long timeo)
2040{
2041 return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
2042}
2043
92f37fd2
ED
2044extern void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
2045 struct sk_buff *skb);
6e3e939f
JB
2046extern void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
2047 struct sk_buff *skb);
92f37fd2 2048
dc6b9b78 2049static inline void
1da177e4
LT
2050sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
2051{
b7aa0bf7 2052 ktime_t kt = skb->tstamp;
20d49473 2053 struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
a61bbcf2 2054
20d49473
PO
2055 /*
2056 * generate control messages if
2057 * - receive time stamping in software requested (SOCK_RCVTSTAMP
2058 * or SOCK_TIMESTAMPING_RX_SOFTWARE)
2059 * - software time stamp available and wanted
2060 * (SOCK_TIMESTAMPING_SOFTWARE)
2061 * - hardware time stamps available and wanted
2062 * (SOCK_TIMESTAMPING_SYS_HARDWARE or
2063 * SOCK_TIMESTAMPING_RAW_HARDWARE)
2064 */
2065 if (sock_flag(sk, SOCK_RCVTSTAMP) ||
2066 sock_flag(sk, SOCK_TIMESTAMPING_RX_SOFTWARE) ||
2067 (kt.tv64 && sock_flag(sk, SOCK_TIMESTAMPING_SOFTWARE)) ||
2068 (hwtstamps->hwtstamp.tv64 &&
2069 sock_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE)) ||
2070 (hwtstamps->syststamp.tv64 &&
2071 sock_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE)))
92f37fd2
ED
2072 __sock_recv_timestamp(msg, sk, skb);
2073 else
b7aa0bf7 2074 sk->sk_stamp = kt;
6e3e939f
JB
2075
2076 if (sock_flag(sk, SOCK_WIFI_STATUS) && skb->wifi_acked_valid)
2077 __sock_recv_wifi_status(msg, sk, skb);
1da177e4
LT
2078}
2079
767dd033
ED
2080extern void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2081 struct sk_buff *skb);
2082
2083static inline void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2084 struct sk_buff *skb)
2085{
2086#define FLAGS_TS_OR_DROPS ((1UL << SOCK_RXQ_OVFL) | \
2087 (1UL << SOCK_RCVTSTAMP) | \
2088 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE) | \
2089 (1UL << SOCK_TIMESTAMPING_SOFTWARE) | \
dc6b9b78 2090 (1UL << SOCK_TIMESTAMPING_RAW_HARDWARE) | \
767dd033
ED
2091 (1UL << SOCK_TIMESTAMPING_SYS_HARDWARE))
2092
2093 if (sk->sk_flags & FLAGS_TS_OR_DROPS)
2094 __sock_recv_ts_and_drops(msg, sk, skb);
2095 else
2096 sk->sk_stamp = skb->tstamp;
2097}
3b885787 2098
20d49473
PO
2099/**
2100 * sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
20d49473 2101 * @sk: socket sending this packet
2244d07b 2102 * @tx_flags: filled with instructions for time stamping
20d49473
PO
2103 *
2104 * Currently only depends on SOCK_TIMESTAMPING* flags. Returns error code if
2105 * parameters are invalid.
2106 */
2244d07b 2107extern int sock_tx_timestamp(struct sock *sk, __u8 *tx_flags);
20d49473 2108
1da177e4
LT
2109/**
2110 * sk_eat_skb - Release a skb if it is no longer needed
4dc3b16b
PP
2111 * @sk: socket to eat this skb from
2112 * @skb: socket buffer to eat
f4b8ea78 2113 * @copied_early: flag indicating whether DMA operations copied this data early
1da177e4
LT
2114 *
2115 * This routine must be called with interrupts disabled or with the socket
2116 * locked so that the sk_buff queue operation is ok.
2117*/
624d1164 2118#ifdef CONFIG_NET_DMA
dc6b9b78 2119static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb, bool copied_early)
624d1164
CL
2120{
2121 __skb_unlink(skb, &sk->sk_receive_queue);
2122 if (!copied_early)
2123 __kfree_skb(skb);
2124 else
2125 __skb_queue_tail(&sk->sk_async_wait_queue, skb);
2126}
2127#else
dc6b9b78 2128static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb, bool copied_early)
1da177e4
LT
2129{
2130 __skb_unlink(skb, &sk->sk_receive_queue);
2131 __kfree_skb(skb);
2132}
624d1164 2133#endif
1da177e4 2134
3b1e0a65
YH
2135static inline
2136struct net *sock_net(const struct sock *sk)
2137{
c2d9ba9b 2138 return read_pnet(&sk->sk_net);
3b1e0a65
YH
2139}
2140
2141static inline
f5aa23fd 2142void sock_net_set(struct sock *sk, struct net *net)
3b1e0a65 2143{
c2d9ba9b 2144 write_pnet(&sk->sk_net, net);
3b1e0a65
YH
2145}
2146
edf02087
DL
2147/*
2148 * Kernel sockets, f.e. rtnl or icmp_socket, are a part of a namespace.
25985edc 2149 * They should not hold a reference to a namespace in order to allow
edf02087
DL
2150 * to stop it.
2151 * Sockets after sk_change_net should be released using sk_release_kernel
2152 */
2153static inline void sk_change_net(struct sock *sk, struct net *net)
2154{
3b1e0a65 2155 put_net(sock_net(sk));
65a18ec5 2156 sock_net_set(sk, hold_net(net));
edf02087
DL
2157}
2158
23542618
KK
2159static inline struct sock *skb_steal_sock(struct sk_buff *skb)
2160{
efc27f8c 2161 if (skb->sk) {
23542618
KK
2162 struct sock *sk = skb->sk;
2163
2164 skb->destructor = NULL;
2165 skb->sk = NULL;
2166 return sk;
2167 }
2168 return NULL;
2169}
2170
20d49473 2171extern void sock_enable_timestamp(struct sock *sk, int flag);
1da177e4 2172extern int sock_get_timestamp(struct sock *, struct timeval __user *);
ae40eb1e 2173extern int sock_get_timestampns(struct sock *, struct timespec __user *);
1da177e4 2174
dc6b9b78
ED
2175/*
2176 * Enable debug/info messages
1da177e4 2177 */
a2a316fd
SH
2178extern int net_msg_warn;
2179#define NETDEBUG(fmt, args...) \
2180 do { if (net_msg_warn) printk(fmt,##args); } while (0)
1da177e4 2181
a2a316fd
SH
2182#define LIMIT_NETDEBUG(fmt, args...) \
2183 do { if (net_msg_warn && net_ratelimit()) printk(fmt,##args); } while(0)
1da177e4 2184
1da177e4
LT
2185extern __u32 sysctl_wmem_max;
2186extern __u32 sysctl_rmem_max;
2187
20380731
ACM
2188extern void sk_init(void);
2189
6baf1f41
DM
2190extern int sysctl_optmem_max;
2191
20380731
ACM
2192extern __u32 sysctl_wmem_default;
2193extern __u32 sysctl_rmem_default;
20380731 2194
1da177e4 2195#endif /* _SOCK_H */