1 /*
2 * INET An implementation of the TCP/IP protocol suite for the LINUX
3 * operating system. INET is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
5 *
6 * Definitions for the AF_INET socket handler.
7 *
8 * Version: @(#)sock.h 1.0.4 05/13/93
9 *
10 * Authors: Ross Biro
11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12 * Corey Minyard <wf-rch!minyard@relay.EU.net>
13 * Florian La Roche <flla@stud.uni-sb.de>
14 *
15 * Fixes:
16 * Alan Cox : Volatiles in skbuff pointers. See
17 * skbuff comments. May be overdone,
18 * better to prove they can be removed
19 * than the reverse.
20 * Alan Cox : Added a zapped field for tcp to note
21 * a socket is reset and must stay shut up
22 * Alan Cox : New fields for options
23 * Pauline Middelink : identd support
24 * Alan Cox : Eliminate low level recv/recvfrom
25 * David S. Miller : New socket lookup architecture.
26 * Steve Whitehouse: Default routines for sock_ops
27 * Arnaldo C. Melo : removed net_pinfo, tp_pinfo and made
28 * protinfo be just a void pointer, as the
29 * protocol specific parts were moved to
30 * respective headers and ipv4/v6, etc now
31 * use private slabcaches for its socks
32 * Pedro Hortas : New flags field for socket options
33 *
34 *
35 * This program is free software; you can redistribute it and/or
36 * modify it under the terms of the GNU General Public License
37 * as published by the Free Software Foundation; either version
38 * 2 of the License, or (at your option) any later version.
39 */
40 #ifndef _SOCK_H
41 #define _SOCK_H
42
43 #include <linux/hardirq.h>
44 #include <linux/kernel.h>
45 #include <linux/list.h>
46 #include <linux/list_nulls.h>
47 #include <linux/timer.h>
48 #include <linux/cache.h>
49 #include <linux/lockdep.h>
50 #include <linux/netdevice.h>
51 #include <linux/skbuff.h> /* struct sk_buff */
52 #include <linux/mm.h>
53 #include <linux/security.h>
54 #include <linux/slab.h>
55 #include <linux/uaccess.h>
56 #include <linux/memcontrol.h>
57 #include <linux/res_counter.h>
58 #include <linux/static_key.h>
59 #include <linux/aio.h>
60 #include <linux/sched.h>
61
62 #include <linux/filter.h>
63 #include <linux/rculist_nulls.h>
64 #include <linux/poll.h>
65
66 #include <linux/atomic.h>
67 #include <net/dst.h>
68 #include <net/checksum.h>
69
70 struct cgroup;
71 struct cgroup_subsys;
72 #ifdef CONFIG_NET
73 int mem_cgroup_sockets_init(struct cgroup *cgrp, struct cgroup_subsys *ss);
74 void mem_cgroup_sockets_destroy(struct cgroup *cgrp);
75 #else
76 static inline
mem_cgroup_sockets_init(struct cgroup * cgrp,struct cgroup_subsys * ss)77 int mem_cgroup_sockets_init(struct cgroup *cgrp, struct cgroup_subsys *ss)
78 {
79 return 0;
80 }
81 static inline
mem_cgroup_sockets_destroy(struct cgroup * cgrp)82 void mem_cgroup_sockets_destroy(struct cgroup *cgrp)
83 {
84 }
85 #endif
86 /*
87 * This structure really needs to be cleaned up.
88 * Most of it is for TCP, and not used by any of
89 * the other protocols.
90 */
91
92 /* Define this to get the SOCK_DBG debugging facility. */
93 #define SOCK_DEBUGGING
94 #ifdef SOCK_DEBUGGING
95 #define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \
96 printk(KERN_DEBUG msg); } while (0)
97 #else
98 /* Validate arguments and do nothing */
99 static inline __printf(2, 3)
SOCK_DEBUG(struct sock * sk,const char * msg,...)100 void SOCK_DEBUG(struct sock *sk, const char *msg, ...)
101 {
102 }
103 #endif
104
105 /* This is the per-socket lock. The spinlock provides a synchronization
106 * between user contexts and software interrupt processing, whereas the
107 * mini-semaphore synchronizes multiple users amongst themselves.
108 */
109 typedef struct {
110 spinlock_t slock;
111 int owned;
112 wait_queue_head_t wq;
113 /*
114 * We express the mutex-alike socket_lock semantics
115 * to the lock validator by explicitly managing
116 * the slock as a lock variant (in addition to
117 * the slock itself):
118 */
119 #ifdef CONFIG_DEBUG_LOCK_ALLOC
120 struct lockdep_map dep_map;
121 #endif
122 } socket_lock_t;
123
124 struct sock;
125 struct proto;
126 struct net;
127
128 /**
129 * struct sock_common - minimal network layer representation of sockets
130 * @skc_daddr: Foreign IPv4 addr
131 * @skc_rcv_saddr: Bound local IPv4 addr
132 * @skc_hash: hash value used with various protocol lookup tables
133 * @skc_u16hashes: two u16 hash values used by UDP lookup tables
134 * @skc_family: network address family
135 * @skc_state: Connection state
136 * @skc_reuse: %SO_REUSEADDR setting
137 * @skc_bound_dev_if: bound device index if != 0
138 * @skc_bind_node: bind hash linkage for various protocol lookup tables
139 * @skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol
140 * @skc_prot: protocol handlers inside a network family
141 * @skc_net: reference to the network namespace of this socket
142 * @skc_node: main hash linkage for various protocol lookup tables
143 * @skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol
144 * @skc_tx_queue_mapping: tx queue number for this connection
145 * @skc_refcnt: reference count
146 *
147 * This is the minimal network layer representation of sockets, the header
148 * for struct sock and struct inet_timewait_sock.
149 */
150 struct sock_common {
151 /* skc_daddr and skc_rcv_saddr must be grouped :
152 * cf INET_MATCH() and INET_TW_MATCH()
153 */
154 __be32 skc_daddr;
155 __be32 skc_rcv_saddr;
156
157 union {
158 unsigned int skc_hash;
159 __u16 skc_u16hashes[2];
160 };
161 unsigned short skc_family;
162 volatile unsigned char skc_state;
163 unsigned char skc_reuse;
164 int skc_bound_dev_if;
165 union {
166 struct hlist_node skc_bind_node;
167 struct hlist_nulls_node skc_portaddr_node;
168 };
169 struct proto *skc_prot;
170 #ifdef CONFIG_NET_NS
171 struct net *skc_net;
172 #endif
173 /*
174 * fields between dontcopy_begin/dontcopy_end
175 * are not copied in sock_copy()
176 */
177 /* private: */
178 int skc_dontcopy_begin[0];
179 /* public: */
180 union {
181 struct hlist_node skc_node;
182 struct hlist_nulls_node skc_nulls_node;
183 };
184 int skc_tx_queue_mapping;
185 atomic_t skc_refcnt;
186 /* private: */
187 int skc_dontcopy_end[0];
188 /* public: */
189 };
190
191 struct cg_proto;
192 /**
193 * struct sock - network layer representation of sockets
194 * @__sk_common: shared layout with inet_timewait_sock
195 * @sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
196 * @sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
197 * @sk_lock: synchronizer
198 * @sk_rcvbuf: size of receive buffer in bytes
199 * @sk_wq: sock wait queue and async head
200 * @sk_dst_cache: destination cache
201 * @sk_dst_lock: destination cache lock
202 * @sk_policy: flow policy
203 * @sk_receive_queue: incoming packets
204 * @sk_wmem_alloc: transmit queue bytes committed
205 * @sk_write_queue: Packet sending queue
206 * @sk_async_wait_queue: DMA copied packets
207 * @sk_omem_alloc: "o" is "option" or "other"
208 * @sk_wmem_queued: persistent queue size
209 * @sk_forward_alloc: space allocated forward
210 * @sk_allocation: allocation mode
211 * @sk_sndbuf: size of send buffer in bytes
212 * @sk_flags: %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE,
213 * %SO_OOBINLINE settings, %SO_TIMESTAMPING settings
214 * @sk_no_check: %SO_NO_CHECK setting, wether or not checkup packets
215 * @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
216 * @sk_route_nocaps: forbidden route capabilities (e.g NETIF_F_GSO_MASK)
217 * @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
218 * @sk_gso_max_size: Maximum GSO segment size to build
219 * @sk_gso_max_segs: Maximum number of GSO segments
220 * @sk_lingertime: %SO_LINGER l_linger setting
221 * @sk_backlog: always used with the per-socket spinlock held
222 * @sk_callback_lock: used with the callbacks in the end of this struct
223 * @sk_error_queue: rarely used
224 * @sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt,
225 * IPV6_ADDRFORM for instance)
226 * @sk_err: last error
227 * @sk_err_soft: errors that don't cause failure but are the cause of a
228 * persistent failure not just 'timed out'
229 * @sk_drops: raw/udp drops counter
230 * @sk_ack_backlog: current listen backlog
231 * @sk_max_ack_backlog: listen backlog set in listen()
232 * @sk_priority: %SO_PRIORITY setting
233 * @sk_cgrp_prioidx: socket group's priority map index
234 * @sk_type: socket type (%SOCK_STREAM, etc)
235 * @sk_protocol: which protocol this socket belongs in this network family
236 * @sk_peer_pid: &struct pid for this socket's peer
237 * @sk_peer_cred: %SO_PEERCRED setting
238 * @sk_rcvlowat: %SO_RCVLOWAT setting
239 * @sk_rcvtimeo: %SO_RCVTIMEO setting
240 * @sk_sndtimeo: %SO_SNDTIMEO setting
241 * @sk_rxhash: flow hash received from netif layer
242 * @sk_filter: socket filtering instructions
243 * @sk_protinfo: private area, net family specific, when not using slab
244 * @sk_timer: sock cleanup timer
245 * @sk_stamp: time stamp of last packet received
246 * @sk_socket: Identd and reporting IO signals
247 * @sk_user_data: RPC layer private data
248 * @sk_sndmsg_page: cached page for sendmsg
249 * @sk_sndmsg_off: cached offset for sendmsg
250 * @sk_peek_off: current peek_offset value
251 * @sk_send_head: front of stuff to transmit
252 * @sk_security: used by security modules
253 * @sk_mark: generic packet mark
254 * @sk_classid: this socket's cgroup classid
255 * @sk_cgrp: this socket's cgroup-specific proto data
256 * @sk_write_pending: a write to stream socket waits to start
257 * @sk_state_change: callback to indicate change in the state of the sock
258 * @sk_data_ready: callback to indicate there is data to be processed
259 * @sk_write_space: callback to indicate there is bf sending space available
260 * @sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
261 * @sk_backlog_rcv: callback to process the backlog
262 * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
263 */
264 struct sock {
265 /*
266 * Now struct inet_timewait_sock also uses sock_common, so please just
267 * don't add nothing before this first member (__sk_common) --acme
268 */
269 struct sock_common __sk_common;
270 #define sk_node __sk_common.skc_node
271 #define sk_nulls_node __sk_common.skc_nulls_node
272 #define sk_refcnt __sk_common.skc_refcnt
273 #define sk_tx_queue_mapping __sk_common.skc_tx_queue_mapping
274
275 #define sk_dontcopy_begin __sk_common.skc_dontcopy_begin
276 #define sk_dontcopy_end __sk_common.skc_dontcopy_end
277 #define sk_hash __sk_common.skc_hash
278 #define sk_family __sk_common.skc_family
279 #define sk_state __sk_common.skc_state
280 #define sk_reuse __sk_common.skc_reuse
281 #define sk_bound_dev_if __sk_common.skc_bound_dev_if
282 #define sk_bind_node __sk_common.skc_bind_node
283 #define sk_prot __sk_common.skc_prot
284 #define sk_net __sk_common.skc_net
285 socket_lock_t sk_lock;
286 struct sk_buff_head sk_receive_queue;
287 /*
288 * The backlog queue is special, it is always used with
289 * the per-socket spinlock held and requires low latency
290 * access. Therefore we special case it's implementation.
291 * Note : rmem_alloc is in this structure to fill a hole
292 * on 64bit arches, not because its logically part of
293 * backlog.
294 */
295 struct {
296 atomic_t rmem_alloc;
297 int len;
298 struct sk_buff *head;
299 struct sk_buff *tail;
300 } sk_backlog;
301 #define sk_rmem_alloc sk_backlog.rmem_alloc
302 int sk_forward_alloc;
303 #ifdef CONFIG_RPS
304 __u32 sk_rxhash;
305 #endif
306 atomic_t sk_drops;
307 int sk_rcvbuf;
308
309 struct sk_filter __rcu *sk_filter;
310 struct socket_wq __rcu *sk_wq;
311
312 #ifdef CONFIG_NET_DMA
313 struct sk_buff_head sk_async_wait_queue;
314 #endif
315
316 #ifdef CONFIG_XFRM
317 struct xfrm_policy *sk_policy[2];
318 #endif
319 unsigned long sk_flags;
320 struct dst_entry *sk_dst_cache;
321 spinlock_t sk_dst_lock;
322 atomic_t sk_wmem_alloc;
323 atomic_t sk_omem_alloc;
324 int sk_sndbuf;
325 struct sk_buff_head sk_write_queue;
326 kmemcheck_bitfield_begin(flags);
327 unsigned int sk_shutdown : 2,
328 sk_no_check : 2,
329 sk_userlocks : 4,
330 sk_protocol : 8,
331 sk_type : 16;
332 kmemcheck_bitfield_end(flags);
333 int sk_wmem_queued;
334 gfp_t sk_allocation;
335 netdev_features_t sk_route_caps;
336 netdev_features_t sk_route_nocaps;
337 int sk_gso_type;
338 unsigned int sk_gso_max_size;
339 u16 sk_gso_max_segs;
340 int sk_rcvlowat;
341 unsigned long sk_lingertime;
342 struct sk_buff_head sk_error_queue;
343 struct proto *sk_prot_creator;
344 rwlock_t sk_callback_lock;
345 int sk_err,
346 sk_err_soft;
347 unsigned short sk_ack_backlog;
348 unsigned short sk_max_ack_backlog;
349 __u32 sk_priority;
350 #ifdef CONFIG_CGROUPS
351 __u32 sk_cgrp_prioidx;
352 #endif
353 struct pid *sk_peer_pid;
354 const struct cred *sk_peer_cred;
355 long sk_rcvtimeo;
356 long sk_sndtimeo;
357 void *sk_protinfo;
358 struct timer_list sk_timer;
359 ktime_t sk_stamp;
360 struct socket *sk_socket;
361 void *sk_user_data;
362 struct page *sk_sndmsg_page;
363 struct sk_buff *sk_send_head;
364 __u32 sk_sndmsg_off;
365 __s32 sk_peek_off;
366 int sk_write_pending;
367 #ifdef CONFIG_SECURITY
368 void *sk_security;
369 #endif
370 __u32 sk_mark;
371 u32 sk_classid;
372 struct cg_proto *sk_cgrp;
373 void (*sk_state_change)(struct sock *sk);
374 void (*sk_data_ready)(struct sock *sk, int bytes);
375 void (*sk_write_space)(struct sock *sk);
376 void (*sk_error_report)(struct sock *sk);
377 int (*sk_backlog_rcv)(struct sock *sk,
378 struct sk_buff *skb);
379 void (*sk_destruct)(struct sock *sk);
380 };
381
sk_peek_offset(struct sock * sk,int flags)382 static inline int sk_peek_offset(struct sock *sk, int flags)
383 {
384 if ((flags & MSG_PEEK) && (sk->sk_peek_off >= 0))
385 return sk->sk_peek_off;
386 else
387 return 0;
388 }
389
sk_peek_offset_bwd(struct sock * sk,int val)390 static inline void sk_peek_offset_bwd(struct sock *sk, int val)
391 {
392 if (sk->sk_peek_off >= 0) {
393 if (sk->sk_peek_off >= val)
394 sk->sk_peek_off -= val;
395 else
396 sk->sk_peek_off = 0;
397 }
398 }
399
sk_peek_offset_fwd(struct sock * sk,int val)400 static inline void sk_peek_offset_fwd(struct sock *sk, int val)
401 {
402 if (sk->sk_peek_off >= 0)
403 sk->sk_peek_off += val;
404 }
405
406 /*
407 * Hashed lists helper routines
408 */
sk_entry(const struct hlist_node * node)409 static inline struct sock *sk_entry(const struct hlist_node *node)
410 {
411 return hlist_entry(node, struct sock, sk_node);
412 }
413
__sk_head(const struct hlist_head * head)414 static inline struct sock *__sk_head(const struct hlist_head *head)
415 {
416 return hlist_entry(head->first, struct sock, sk_node);
417 }
418
sk_head(const struct hlist_head * head)419 static inline struct sock *sk_head(const struct hlist_head *head)
420 {
421 return hlist_empty(head) ? NULL : __sk_head(head);
422 }
423
__sk_nulls_head(const struct hlist_nulls_head * head)424 static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head)
425 {
426 return hlist_nulls_entry(head->first, struct sock, sk_nulls_node);
427 }
428
sk_nulls_head(const struct hlist_nulls_head * head)429 static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head)
430 {
431 return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head);
432 }
433
sk_next(const struct sock * sk)434 static inline struct sock *sk_next(const struct sock *sk)
435 {
436 return sk->sk_node.next ?
437 hlist_entry(sk->sk_node.next, struct sock, sk_node) : NULL;
438 }
439
sk_nulls_next(const struct sock * sk)440 static inline struct sock *sk_nulls_next(const struct sock *sk)
441 {
442 return (!is_a_nulls(sk->sk_nulls_node.next)) ?
443 hlist_nulls_entry(sk->sk_nulls_node.next,
444 struct sock, sk_nulls_node) :
445 NULL;
446 }
447
sk_unhashed(const struct sock * sk)448 static inline int sk_unhashed(const struct sock *sk)
449 {
450 return hlist_unhashed(&sk->sk_node);
451 }
452
sk_hashed(const struct sock * sk)453 static inline int sk_hashed(const struct sock *sk)
454 {
455 return !sk_unhashed(sk);
456 }
457
sk_node_init(struct hlist_node * node)458 static __inline__ void sk_node_init(struct hlist_node *node)
459 {
460 node->pprev = NULL;
461 }
462
sk_nulls_node_init(struct hlist_nulls_node * node)463 static __inline__ void sk_nulls_node_init(struct hlist_nulls_node *node)
464 {
465 node->pprev = NULL;
466 }
467
__sk_del_node(struct sock * sk)468 static __inline__ void __sk_del_node(struct sock *sk)
469 {
470 __hlist_del(&sk->sk_node);
471 }
472
473 /* NB: equivalent to hlist_del_init_rcu */
__sk_del_node_init(struct sock * sk)474 static __inline__ int __sk_del_node_init(struct sock *sk)
475 {
476 if (sk_hashed(sk)) {
477 __sk_del_node(sk);
478 sk_node_init(&sk->sk_node);
479 return 1;
480 }
481 return 0;
482 }
483
484 /* Grab socket reference count. This operation is valid only
485 when sk is ALREADY grabbed f.e. it is found in hash table
486 or a list and the lookup is made under lock preventing hash table
487 modifications.
488 */
489
sock_hold(struct sock * sk)490 static inline void sock_hold(struct sock *sk)
491 {
492 atomic_inc(&sk->sk_refcnt);
493 }
494
495 /* Ungrab socket in the context, which assumes that socket refcnt
496 cannot hit zero, f.e. it is true in context of any socketcall.
497 */
__sock_put(struct sock * sk)498 static inline void __sock_put(struct sock *sk)
499 {
500 atomic_dec(&sk->sk_refcnt);
501 }
502
sk_del_node_init(struct sock * sk)503 static __inline__ int sk_del_node_init(struct sock *sk)
504 {
505 int rc = __sk_del_node_init(sk);
506
507 if (rc) {
508 /* paranoid for a while -acme */
509 WARN_ON(atomic_read(&sk->sk_refcnt) == 1);
510 __sock_put(sk);
511 }
512 return rc;
513 }
514 #define sk_del_node_init_rcu(sk) sk_del_node_init(sk)
515
__sk_nulls_del_node_init_rcu(struct sock * sk)516 static __inline__ int __sk_nulls_del_node_init_rcu(struct sock *sk)
517 {
518 if (sk_hashed(sk)) {
519 hlist_nulls_del_init_rcu(&sk->sk_nulls_node);
520 return 1;
521 }
522 return 0;
523 }
524
sk_nulls_del_node_init_rcu(struct sock * sk)525 static __inline__ int sk_nulls_del_node_init_rcu(struct sock *sk)
526 {
527 int rc = __sk_nulls_del_node_init_rcu(sk);
528
529 if (rc) {
530 /* paranoid for a while -acme */
531 WARN_ON(atomic_read(&sk->sk_refcnt) == 1);
532 __sock_put(sk);
533 }
534 return rc;
535 }
536
__sk_add_node(struct sock * sk,struct hlist_head * list)537 static __inline__ void __sk_add_node(struct sock *sk, struct hlist_head *list)
538 {
539 hlist_add_head(&sk->sk_node, list);
540 }
541
sk_add_node(struct sock * sk,struct hlist_head * list)542 static __inline__ void sk_add_node(struct sock *sk, struct hlist_head *list)
543 {
544 sock_hold(sk);
545 __sk_add_node(sk, list);
546 }
547
sk_add_node_rcu(struct sock * sk,struct hlist_head * list)548 static __inline__ void sk_add_node_rcu(struct sock *sk, struct hlist_head *list)
549 {
550 sock_hold(sk);
551 hlist_add_head_rcu(&sk->sk_node, list);
552 }
553
__sk_nulls_add_node_rcu(struct sock * sk,struct hlist_nulls_head * list)554 static __inline__ void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
555 {
556 hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list);
557 }
558
sk_nulls_add_node_rcu(struct sock * sk,struct hlist_nulls_head * list)559 static __inline__ void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
560 {
561 sock_hold(sk);
562 __sk_nulls_add_node_rcu(sk, list);
563 }
564
__sk_del_bind_node(struct sock * sk)565 static __inline__ void __sk_del_bind_node(struct sock *sk)
566 {
567 __hlist_del(&sk->sk_bind_node);
568 }
569
sk_add_bind_node(struct sock * sk,struct hlist_head * list)570 static __inline__ void sk_add_bind_node(struct sock *sk,
571 struct hlist_head *list)
572 {
573 hlist_add_head(&sk->sk_bind_node, list);
574 }
575
576 #define sk_for_each(__sk, node, list) \
577 hlist_for_each_entry(__sk, node, list, sk_node)
578 #define sk_for_each_rcu(__sk, node, list) \
579 hlist_for_each_entry_rcu(__sk, node, list, sk_node)
580 #define sk_nulls_for_each(__sk, node, list) \
581 hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)
582 #define sk_nulls_for_each_rcu(__sk, node, list) \
583 hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)
584 #define sk_for_each_from(__sk, node) \
585 if (__sk && ({ node = &(__sk)->sk_node; 1; })) \
586 hlist_for_each_entry_from(__sk, node, sk_node)
587 #define sk_nulls_for_each_from(__sk, node) \
588 if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \
589 hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node)
590 #define sk_for_each_safe(__sk, node, tmp, list) \
591 hlist_for_each_entry_safe(__sk, node, tmp, list, sk_node)
592 #define sk_for_each_bound(__sk, node, list) \
593 hlist_for_each_entry(__sk, node, list, sk_bind_node)
594
595 /* Sock flags */
596 enum sock_flags {
597 SOCK_DEAD,
598 SOCK_DONE,
599 SOCK_URGINLINE,
600 SOCK_KEEPOPEN,
601 SOCK_LINGER,
602 SOCK_DESTROY,
603 SOCK_BROADCAST,
604 SOCK_TIMESTAMP,
605 SOCK_ZAPPED,
606 SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */
607 SOCK_DBG, /* %SO_DEBUG setting */
608 SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
609 SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */
610 SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
611 SOCK_QUEUE_SHRUNK, /* write queue has been shrunk recently */
612 SOCK_TIMESTAMPING_TX_HARDWARE, /* %SOF_TIMESTAMPING_TX_HARDWARE */
613 SOCK_TIMESTAMPING_TX_SOFTWARE, /* %SOF_TIMESTAMPING_TX_SOFTWARE */
614 SOCK_TIMESTAMPING_RX_HARDWARE, /* %SOF_TIMESTAMPING_RX_HARDWARE */
615 SOCK_TIMESTAMPING_RX_SOFTWARE, /* %SOF_TIMESTAMPING_RX_SOFTWARE */
616 SOCK_TIMESTAMPING_SOFTWARE, /* %SOF_TIMESTAMPING_SOFTWARE */
617 SOCK_TIMESTAMPING_RAW_HARDWARE, /* %SOF_TIMESTAMPING_RAW_HARDWARE */
618 SOCK_TIMESTAMPING_SYS_HARDWARE, /* %SOF_TIMESTAMPING_SYS_HARDWARE */
619 SOCK_FASYNC, /* fasync() active */
620 SOCK_RXQ_OVFL,
621 SOCK_ZEROCOPY, /* buffers from userspace */
622 SOCK_WIFI_STATUS, /* push wifi status to userspace */
623 SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS.
624 * Will use last 4 bytes of packet sent from
625 * user-space instead.
626 */
627 };
628
sock_copy_flags(struct sock * nsk,struct sock * osk)629 static inline void sock_copy_flags(struct sock *nsk, struct sock *osk)
630 {
631 nsk->sk_flags = osk->sk_flags;
632 }
633
sock_set_flag(struct sock * sk,enum sock_flags flag)634 static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
635 {
636 __set_bit(flag, &sk->sk_flags);
637 }
638
sock_reset_flag(struct sock * sk,enum sock_flags flag)639 static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag)
640 {
641 __clear_bit(flag, &sk->sk_flags);
642 }
643
sock_flag(struct sock * sk,enum sock_flags flag)644 static inline int sock_flag(struct sock *sk, enum sock_flags flag)
645 {
646 return test_bit(flag, &sk->sk_flags);
647 }
648
sk_acceptq_removed(struct sock * sk)649 static inline void sk_acceptq_removed(struct sock *sk)
650 {
651 sk->sk_ack_backlog--;
652 }
653
sk_acceptq_added(struct sock * sk)654 static inline void sk_acceptq_added(struct sock *sk)
655 {
656 sk->sk_ack_backlog++;
657 }
658
sk_acceptq_is_full(struct sock * sk)659 static inline int sk_acceptq_is_full(struct sock *sk)
660 {
661 return sk->sk_ack_backlog > sk->sk_max_ack_backlog;
662 }
663
664 /*
665 * Compute minimal free write space needed to queue new packets.
666 */
sk_stream_min_wspace(struct sock * sk)667 static inline int sk_stream_min_wspace(struct sock *sk)
668 {
669 return sk->sk_wmem_queued >> 1;
670 }
671
sk_stream_wspace(struct sock * sk)672 static inline int sk_stream_wspace(struct sock *sk)
673 {
674 return sk->sk_sndbuf - sk->sk_wmem_queued;
675 }
676
677 extern void sk_stream_write_space(struct sock *sk);
678
sk_stream_memory_free(struct sock * sk)679 static inline int sk_stream_memory_free(struct sock *sk)
680 {
681 return sk->sk_wmem_queued < sk->sk_sndbuf;
682 }
683
684 /* OOB backlog add */
__sk_add_backlog(struct sock * sk,struct sk_buff * skb)685 static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
686 {
687 /* dont let skb dst not refcounted, we are going to leave rcu lock */
688 skb_dst_force(skb);
689
690 if (!sk->sk_backlog.tail)
691 sk->sk_backlog.head = skb;
692 else
693 sk->sk_backlog.tail->next = skb;
694
695 sk->sk_backlog.tail = skb;
696 skb->next = NULL;
697 }
698
699 /*
700 * Take into account size of receive queue and backlog queue
701 * Do not take into account this skb truesize,
702 * to allow even a single big packet to come.
703 */
sk_rcvqueues_full(const struct sock * sk,const struct sk_buff * skb)704 static inline bool sk_rcvqueues_full(const struct sock *sk, const struct sk_buff *skb)
705 {
706 unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc);
707
708 return qsize > sk->sk_rcvbuf;
709 }
710
711 /* The per-socket spinlock must be held here. */
sk_add_backlog(struct sock * sk,struct sk_buff * skb)712 static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb)
713 {
714 if (sk_rcvqueues_full(sk, skb))
715 return -ENOBUFS;
716
717 __sk_add_backlog(sk, skb);
718 sk->sk_backlog.len += skb->truesize;
719 return 0;
720 }
721
sk_backlog_rcv(struct sock * sk,struct sk_buff * skb)722 static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
723 {
724 return sk->sk_backlog_rcv(sk, skb);
725 }
726
sock_rps_record_flow(const struct sock * sk)727 static inline void sock_rps_record_flow(const struct sock *sk)
728 {
729 #ifdef CONFIG_RPS
730 struct rps_sock_flow_table *sock_flow_table;
731
732 rcu_read_lock();
733 sock_flow_table = rcu_dereference(rps_sock_flow_table);
734 rps_record_sock_flow(sock_flow_table, sk->sk_rxhash);
735 rcu_read_unlock();
736 #endif
737 }
738
sock_rps_reset_flow(const struct sock * sk)739 static inline void sock_rps_reset_flow(const struct sock *sk)
740 {
741 #ifdef CONFIG_RPS
742 struct rps_sock_flow_table *sock_flow_table;
743
744 rcu_read_lock();
745 sock_flow_table = rcu_dereference(rps_sock_flow_table);
746 rps_reset_sock_flow(sock_flow_table, sk->sk_rxhash);
747 rcu_read_unlock();
748 #endif
749 }
750
sock_rps_save_rxhash(struct sock * sk,const struct sk_buff * skb)751 static inline void sock_rps_save_rxhash(struct sock *sk,
752 const struct sk_buff *skb)
753 {
754 #ifdef CONFIG_RPS
755 if (unlikely(sk->sk_rxhash != skb->rxhash)) {
756 sock_rps_reset_flow(sk);
757 sk->sk_rxhash = skb->rxhash;
758 }
759 #endif
760 }
761
sock_rps_reset_rxhash(struct sock * sk)762 static inline void sock_rps_reset_rxhash(struct sock *sk)
763 {
764 #ifdef CONFIG_RPS
765 sock_rps_reset_flow(sk);
766 sk->sk_rxhash = 0;
767 #endif
768 }
769
770 #define sk_wait_event(__sk, __timeo, __condition) \
771 ({ int __rc; \
772 release_sock(__sk); \
773 __rc = __condition; \
774 if (!__rc) { \
775 *(__timeo) = schedule_timeout(*(__timeo)); \
776 } \
777 lock_sock(__sk); \
778 __rc = __condition; \
779 __rc; \
780 })
781
782 extern int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
783 extern int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
784 extern void sk_stream_wait_close(struct sock *sk, long timeo_p);
785 extern int sk_stream_error(struct sock *sk, int flags, int err);
786 extern void sk_stream_kill_queues(struct sock *sk);
787
788 extern int sk_wait_data(struct sock *sk, long *timeo);
789
790 struct request_sock_ops;
791 struct timewait_sock_ops;
792 struct inet_hashinfo;
793 struct raw_hashinfo;
794 struct module;
795
796 /*
797 * caches using SLAB_DESTROY_BY_RCU should let .next pointer from nulls nodes
798 * un-modified. Special care is taken when initializing object to zero.
799 */
sk_prot_clear_nulls(struct sock * sk,int size)800 static inline void sk_prot_clear_nulls(struct sock *sk, int size)
801 {
802 if (offsetof(struct sock, sk_node.next) != 0)
803 memset(sk, 0, offsetof(struct sock, sk_node.next));
804 memset(&sk->sk_node.pprev, 0,
805 size - offsetof(struct sock, sk_node.pprev));
806 }
807
808 /* Networking protocol blocks we attach to sockets.
809 * socket layer -> transport layer interface
810 * transport -> network interface is defined by struct inet_proto
811 */
812 struct proto {
813 void (*close)(struct sock *sk,
814 long timeout);
815 int (*connect)(struct sock *sk,
816 struct sockaddr *uaddr,
817 int addr_len);
818 int (*disconnect)(struct sock *sk, int flags);
819
820 struct sock * (*accept) (struct sock *sk, int flags, int *err);
821
822 int (*ioctl)(struct sock *sk, int cmd,
823 unsigned long arg);
824 int (*init)(struct sock *sk);
825 void (*destroy)(struct sock *sk);
826 void (*shutdown)(struct sock *sk, int how);
827 int (*setsockopt)(struct sock *sk, int level,
828 int optname, char __user *optval,
829 unsigned int optlen);
830 int (*getsockopt)(struct sock *sk, int level,
831 int optname, char __user *optval,
832 int __user *option);
833 #ifdef CONFIG_COMPAT
834 int (*compat_setsockopt)(struct sock *sk,
835 int level,
836 int optname, char __user *optval,
837 unsigned int optlen);
838 int (*compat_getsockopt)(struct sock *sk,
839 int level,
840 int optname, char __user *optval,
841 int __user *option);
842 int (*compat_ioctl)(struct sock *sk,
843 unsigned int cmd, unsigned long arg);
844 #endif
845 int (*sendmsg)(struct kiocb *iocb, struct sock *sk,
846 struct msghdr *msg, size_t len);
847 int (*recvmsg)(struct kiocb *iocb, struct sock *sk,
848 struct msghdr *msg,
849 size_t len, int noblock, int flags,
850 int *addr_len);
851 int (*sendpage)(struct sock *sk, struct page *page,
852 int offset, size_t size, int flags);
853 int (*bind)(struct sock *sk,
854 struct sockaddr *uaddr, int addr_len);
855
856 int (*backlog_rcv) (struct sock *sk,
857 struct sk_buff *skb);
858
859 /* Keeping track of sk's, looking them up, and port selection methods. */
860 void (*hash)(struct sock *sk);
861 void (*unhash)(struct sock *sk);
862 void (*rehash)(struct sock *sk);
863 int (*get_port)(struct sock *sk, unsigned short snum);
864 void (*clear_sk)(struct sock *sk, int size);
865
866 /* Keeping track of sockets in use */
867 #ifdef CONFIG_PROC_FS
868 unsigned int inuse_idx;
869 #endif
870
871 /* Memory pressure */
872 void (*enter_memory_pressure)(struct sock *sk);
873 atomic_long_t *memory_allocated; /* Current allocated memory. */
874 struct percpu_counter *sockets_allocated; /* Current number of sockets. */
875 /*
876 * Pressure flag: try to collapse.
877 * Technical note: it is used by multiple contexts non atomically.
878 * All the __sk_mem_schedule() is of this nature: accounting
879 * is strict, actions are advisory and have some latency.
880 */
881 int *memory_pressure;
882 long *sysctl_mem;
883 int *sysctl_wmem;
884 int *sysctl_rmem;
885 int max_header;
886 bool no_autobind;
887
888 struct kmem_cache *slab;
889 unsigned int obj_size;
890 int slab_flags;
891
892 struct percpu_counter *orphan_count;
893
894 struct request_sock_ops *rsk_prot;
895 struct timewait_sock_ops *twsk_prot;
896
897 union {
898 struct inet_hashinfo *hashinfo;
899 struct udp_table *udp_table;
900 struct raw_hashinfo *raw_hash;
901 } h;
902
903 struct module *owner;
904
905 char name[32];
906
907 struct list_head node;
908 #ifdef SOCK_REFCNT_DEBUG
909 atomic_t socks;
910 #endif
911 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_KMEM
912 /*
913 * cgroup specific init/deinit functions. Called once for all
914 * protocols that implement it, from cgroups populate function.
915 * This function has to setup any files the protocol want to
916 * appear in the kmem cgroup filesystem.
917 */
918 int (*init_cgroup)(struct cgroup *cgrp,
919 struct cgroup_subsys *ss);
920 void (*destroy_cgroup)(struct cgroup *cgrp);
921 struct cg_proto *(*proto_cgroup)(struct mem_cgroup *memcg);
922 #endif
923 };
924
925 struct cg_proto {
926 void (*enter_memory_pressure)(struct sock *sk);
927 struct res_counter *memory_allocated; /* Current allocated memory. */
928 struct percpu_counter *sockets_allocated; /* Current number of sockets. */
929 int *memory_pressure;
930 long *sysctl_mem;
931 /*
932 * memcg field is used to find which memcg we belong directly
933 * Each memcg struct can hold more than one cg_proto, so container_of
934 * won't really cut.
935 *
936 * The elegant solution would be having an inverse function to
937 * proto_cgroup in struct proto, but that means polluting the structure
938 * for everybody, instead of just for memcg users.
939 */
940 struct mem_cgroup *memcg;
941 };
942
943 extern int proto_register(struct proto *prot, int alloc_slab);
944 extern void proto_unregister(struct proto *prot);
945
946 #ifdef SOCK_REFCNT_DEBUG
sk_refcnt_debug_inc(struct sock * sk)947 static inline void sk_refcnt_debug_inc(struct sock *sk)
948 {
949 atomic_inc(&sk->sk_prot->socks);
950 }
951
sk_refcnt_debug_dec(struct sock * sk)952 static inline void sk_refcnt_debug_dec(struct sock *sk)
953 {
954 atomic_dec(&sk->sk_prot->socks);
955 printk(KERN_DEBUG "%s socket %p released, %d are still alive\n",
956 sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks));
957 }
958
sk_refcnt_debug_release(const struct sock * sk)959 static inline void sk_refcnt_debug_release(const struct sock *sk)
960 {
961 if (atomic_read(&sk->sk_refcnt) != 1)
962 printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n",
963 sk->sk_prot->name, sk, atomic_read(&sk->sk_refcnt));
964 }
965 #else /* SOCK_REFCNT_DEBUG */
966 #define sk_refcnt_debug_inc(sk) do { } while (0)
967 #define sk_refcnt_debug_dec(sk) do { } while (0)
968 #define sk_refcnt_debug_release(sk) do { } while (0)
969 #endif /* SOCK_REFCNT_DEBUG */
970
971 #if defined(CONFIG_CGROUP_MEM_RES_CTLR_KMEM) && defined(CONFIG_NET)
972 extern struct static_key memcg_socket_limit_enabled;
parent_cg_proto(struct proto * proto,struct cg_proto * cg_proto)973 static inline struct cg_proto *parent_cg_proto(struct proto *proto,
974 struct cg_proto *cg_proto)
975 {
976 return proto->proto_cgroup(parent_mem_cgroup(cg_proto->memcg));
977 }
978 #define mem_cgroup_sockets_enabled static_key_false(&memcg_socket_limit_enabled)
979 #else
980 #define mem_cgroup_sockets_enabled 0
parent_cg_proto(struct proto * proto,struct cg_proto * cg_proto)981 static inline struct cg_proto *parent_cg_proto(struct proto *proto,
982 struct cg_proto *cg_proto)
983 {
984 return NULL;
985 }
986 #endif
987
988
sk_has_memory_pressure(const struct sock * sk)989 static inline bool sk_has_memory_pressure(const struct sock *sk)
990 {
991 return sk->sk_prot->memory_pressure != NULL;
992 }
993
sk_under_memory_pressure(const struct sock * sk)994 static inline bool sk_under_memory_pressure(const struct sock *sk)
995 {
996 if (!sk->sk_prot->memory_pressure)
997 return false;
998
999 if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1000 return !!*sk->sk_cgrp->memory_pressure;
1001
1002 return !!*sk->sk_prot->memory_pressure;
1003 }
1004
sk_leave_memory_pressure(struct sock * sk)1005 static inline void sk_leave_memory_pressure(struct sock *sk)
1006 {
1007 int *memory_pressure = sk->sk_prot->memory_pressure;
1008
1009 if (!memory_pressure)
1010 return;
1011
1012 if (*memory_pressure)
1013 *memory_pressure = 0;
1014
1015 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1016 struct cg_proto *cg_proto = sk->sk_cgrp;
1017 struct proto *prot = sk->sk_prot;
1018
1019 for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto))
1020 if (*cg_proto->memory_pressure)
1021 *cg_proto->memory_pressure = 0;
1022 }
1023
1024 }
1025
sk_enter_memory_pressure(struct sock * sk)1026 static inline void sk_enter_memory_pressure(struct sock *sk)
1027 {
1028 if (!sk->sk_prot->enter_memory_pressure)
1029 return;
1030
1031 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1032 struct cg_proto *cg_proto = sk->sk_cgrp;
1033 struct proto *prot = sk->sk_prot;
1034
1035 for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto))
1036 cg_proto->enter_memory_pressure(sk);
1037 }
1038
1039 sk->sk_prot->enter_memory_pressure(sk);
1040 }
1041
sk_prot_mem_limits(const struct sock * sk,int index)1042 static inline long sk_prot_mem_limits(const struct sock *sk, int index)
1043 {
1044 long *prot = sk->sk_prot->sysctl_mem;
1045 if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1046 prot = sk->sk_cgrp->sysctl_mem;
1047 return prot[index];
1048 }
1049
memcg_memory_allocated_add(struct cg_proto * prot,unsigned long amt,int * parent_status)1050 static inline void memcg_memory_allocated_add(struct cg_proto *prot,
1051 unsigned long amt,
1052 int *parent_status)
1053 {
1054 struct res_counter *fail;
1055 int ret;
1056
1057 ret = res_counter_charge_nofail(prot->memory_allocated,
1058 amt << PAGE_SHIFT, &fail);
1059 if (ret < 0)
1060 *parent_status = OVER_LIMIT;
1061 }
1062
memcg_memory_allocated_sub(struct cg_proto * prot,unsigned long amt)1063 static inline void memcg_memory_allocated_sub(struct cg_proto *prot,
1064 unsigned long amt)
1065 {
1066 res_counter_uncharge(prot->memory_allocated, amt << PAGE_SHIFT);
1067 }
1068
memcg_memory_allocated_read(struct cg_proto * prot)1069 static inline u64 memcg_memory_allocated_read(struct cg_proto *prot)
1070 {
1071 u64 ret;
1072 ret = res_counter_read_u64(prot->memory_allocated, RES_USAGE);
1073 return ret >> PAGE_SHIFT;
1074 }
1075
1076 static inline long
sk_memory_allocated(const struct sock * sk)1077 sk_memory_allocated(const struct sock *sk)
1078 {
1079 struct proto *prot = sk->sk_prot;
1080 if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1081 return memcg_memory_allocated_read(sk->sk_cgrp);
1082
1083 return atomic_long_read(prot->memory_allocated);
1084 }
1085
1086 static inline long
sk_memory_allocated_add(struct sock * sk,int amt,int * parent_status)1087 sk_memory_allocated_add(struct sock *sk, int amt, int *parent_status)
1088 {
1089 struct proto *prot = sk->sk_prot;
1090
1091 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1092 memcg_memory_allocated_add(sk->sk_cgrp, amt, parent_status);
1093 /* update the root cgroup regardless */
1094 atomic_long_add_return(amt, prot->memory_allocated);
1095 return memcg_memory_allocated_read(sk->sk_cgrp);
1096 }
1097
1098 return atomic_long_add_return(amt, prot->memory_allocated);
1099 }
1100
1101 static inline void
sk_memory_allocated_sub(struct sock * sk,int amt)1102 sk_memory_allocated_sub(struct sock *sk, int amt)
1103 {
1104 struct proto *prot = sk->sk_prot;
1105
1106 if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1107 memcg_memory_allocated_sub(sk->sk_cgrp, amt);
1108
1109 atomic_long_sub(amt, prot->memory_allocated);
1110 }
1111
sk_sockets_allocated_dec(struct sock * sk)1112 static inline void sk_sockets_allocated_dec(struct sock *sk)
1113 {
1114 struct proto *prot = sk->sk_prot;
1115
1116 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1117 struct cg_proto *cg_proto = sk->sk_cgrp;
1118
1119 for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto))
1120 percpu_counter_dec(cg_proto->sockets_allocated);
1121 }
1122
1123 percpu_counter_dec(prot->sockets_allocated);
1124 }
1125
sk_sockets_allocated_inc(struct sock * sk)1126 static inline void sk_sockets_allocated_inc(struct sock *sk)
1127 {
1128 struct proto *prot = sk->sk_prot;
1129
1130 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1131 struct cg_proto *cg_proto = sk->sk_cgrp;
1132
1133 for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto))
1134 percpu_counter_inc(cg_proto->sockets_allocated);
1135 }
1136
1137 percpu_counter_inc(prot->sockets_allocated);
1138 }
1139
1140 static inline int
sk_sockets_allocated_read_positive(struct sock * sk)1141 sk_sockets_allocated_read_positive(struct sock *sk)
1142 {
1143 struct proto *prot = sk->sk_prot;
1144
1145 if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1146 return percpu_counter_read_positive(sk->sk_cgrp->sockets_allocated);
1147
1148 return percpu_counter_read_positive(prot->sockets_allocated);
1149 }
1150
1151 static inline int
proto_sockets_allocated_sum_positive(struct proto * prot)1152 proto_sockets_allocated_sum_positive(struct proto *prot)
1153 {
1154 return percpu_counter_sum_positive(prot->sockets_allocated);
1155 }
1156
1157 static inline long
proto_memory_allocated(struct proto * prot)1158 proto_memory_allocated(struct proto *prot)
1159 {
1160 return atomic_long_read(prot->memory_allocated);
1161 }
1162
1163 static inline bool
proto_memory_pressure(struct proto * prot)1164 proto_memory_pressure(struct proto *prot)
1165 {
1166 if (!prot->memory_pressure)
1167 return false;
1168 return !!*prot->memory_pressure;
1169 }
1170
1171
1172 #ifdef CONFIG_PROC_FS
1173 /* Called with local bh disabled */
1174 extern void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc);
1175 extern int sock_prot_inuse_get(struct net *net, struct proto *proto);
1176 #else
sock_prot_inuse_add(struct net * net,struct proto * prot,int inc)1177 static void inline sock_prot_inuse_add(struct net *net, struct proto *prot,
1178 int inc)
1179 {
1180 }
1181 #endif
1182
1183
1184 /* With per-bucket locks this operation is not-atomic, so that
1185 * this version is not worse.
1186 */
__sk_prot_rehash(struct sock * sk)1187 static inline void __sk_prot_rehash(struct sock *sk)
1188 {
1189 sk->sk_prot->unhash(sk);
1190 sk->sk_prot->hash(sk);
1191 }
1192
1193 void sk_prot_clear_portaddr_nulls(struct sock *sk, int size);
1194
1195 /* About 10 seconds */
1196 #define SOCK_DESTROY_TIME (10*HZ)
1197
1198 /* Sockets 0-1023 can't be bound to unless you are superuser */
1199 #define PROT_SOCK 1024
1200
1201 #define SHUTDOWN_MASK 3
1202 #define RCV_SHUTDOWN 1
1203 #define SEND_SHUTDOWN 2
1204
1205 #define SOCK_SNDBUF_LOCK 1
1206 #define SOCK_RCVBUF_LOCK 2
1207 #define SOCK_BINDADDR_LOCK 4
1208 #define SOCK_BINDPORT_LOCK 8
1209
1210 /* sock_iocb: used to kick off async processing of socket ios */
1211 struct sock_iocb {
1212 struct list_head list;
1213
1214 int flags;
1215 int size;
1216 struct socket *sock;
1217 struct sock *sk;
1218 struct scm_cookie *scm;
1219 struct msghdr *msg, async_msg;
1220 struct kiocb *kiocb;
1221 };
1222
kiocb_to_siocb(struct kiocb * iocb)1223 static inline struct sock_iocb *kiocb_to_siocb(struct kiocb *iocb)
1224 {
1225 return (struct sock_iocb *)iocb->private;
1226 }
1227
siocb_to_kiocb(struct sock_iocb * si)1228 static inline struct kiocb *siocb_to_kiocb(struct sock_iocb *si)
1229 {
1230 return si->kiocb;
1231 }
1232
1233 struct socket_alloc {
1234 struct socket socket;
1235 struct inode vfs_inode;
1236 };
1237
SOCKET_I(struct inode * inode)1238 static inline struct socket *SOCKET_I(struct inode *inode)
1239 {
1240 return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
1241 }
1242
SOCK_INODE(struct socket * socket)1243 static inline struct inode *SOCK_INODE(struct socket *socket)
1244 {
1245 return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
1246 }
1247
1248 /*
1249 * Functions for memory accounting
1250 */
1251 extern int __sk_mem_schedule(struct sock *sk, int size, int kind);
1252 extern void __sk_mem_reclaim(struct sock *sk);
1253
1254 #define SK_MEM_QUANTUM ((int)PAGE_SIZE)
1255 #define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM)
1256 #define SK_MEM_SEND 0
1257 #define SK_MEM_RECV 1
1258
sk_mem_pages(int amt)1259 static inline int sk_mem_pages(int amt)
1260 {
1261 return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT;
1262 }
1263
sk_has_account(struct sock * sk)1264 static inline int sk_has_account(struct sock *sk)
1265 {
1266 /* return true if protocol supports memory accounting */
1267 return !!sk->sk_prot->memory_allocated;
1268 }
1269
sk_wmem_schedule(struct sock * sk,int size)1270 static inline int sk_wmem_schedule(struct sock *sk, int size)
1271 {
1272 if (!sk_has_account(sk))
1273 return 1;
1274 return size <= sk->sk_forward_alloc ||
1275 __sk_mem_schedule(sk, size, SK_MEM_SEND);
1276 }
1277
sk_rmem_schedule(struct sock * sk,int size)1278 static inline int sk_rmem_schedule(struct sock *sk, int size)
1279 {
1280 if (!sk_has_account(sk))
1281 return 1;
1282 return size <= sk->sk_forward_alloc ||
1283 __sk_mem_schedule(sk, size, SK_MEM_RECV);
1284 }
1285
sk_mem_reclaim(struct sock * sk)1286 static inline void sk_mem_reclaim(struct sock *sk)
1287 {
1288 if (!sk_has_account(sk))
1289 return;
1290 if (sk->sk_forward_alloc >= SK_MEM_QUANTUM)
1291 __sk_mem_reclaim(sk);
1292 }
1293
sk_mem_reclaim_partial(struct sock * sk)1294 static inline void sk_mem_reclaim_partial(struct sock *sk)
1295 {
1296 if (!sk_has_account(sk))
1297 return;
1298 if (sk->sk_forward_alloc > SK_MEM_QUANTUM)
1299 __sk_mem_reclaim(sk);
1300 }
1301
sk_mem_charge(struct sock * sk,int size)1302 static inline void sk_mem_charge(struct sock *sk, int size)
1303 {
1304 if (!sk_has_account(sk))
1305 return;
1306 sk->sk_forward_alloc -= size;
1307 }
1308
sk_mem_uncharge(struct sock * sk,int size)1309 static inline void sk_mem_uncharge(struct sock *sk, int size)
1310 {
1311 if (!sk_has_account(sk))
1312 return;
1313 sk->sk_forward_alloc += size;
1314 }
1315
sk_wmem_free_skb(struct sock * sk,struct sk_buff * skb)1316 static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb)
1317 {
1318 sock_set_flag(sk, SOCK_QUEUE_SHRUNK);
1319 sk->sk_wmem_queued -= skb->truesize;
1320 sk_mem_uncharge(sk, skb->truesize);
1321 __kfree_skb(skb);
1322 }
1323
1324 /* Used by processes to "lock" a socket state, so that
1325 * interrupts and bottom half handlers won't change it
1326 * from under us. It essentially blocks any incoming
1327 * packets, so that we won't get any new data or any
1328 * packets that change the state of the socket.
1329 *
1330 * While locked, BH processing will add new packets to
1331 * the backlog queue. This queue is processed by the
1332 * owner of the socket lock right before it is released.
1333 *
1334 * Since ~2.3.5 it is also exclusive sleep lock serializing
1335 * accesses from user process context.
1336 */
1337 #define sock_owned_by_user(sk) ((sk)->sk_lock.owned)
1338
1339 /*
1340 * Macro so as to not evaluate some arguments when
1341 * lockdep is not enabled.
1342 *
1343 * Mark both the sk_lock and the sk_lock.slock as a
1344 * per-address-family lock class.
1345 */
1346 #define sock_lock_init_class_and_name(sk, sname, skey, name, key) \
1347 do { \
1348 sk->sk_lock.owned = 0; \
1349 init_waitqueue_head(&sk->sk_lock.wq); \
1350 spin_lock_init(&(sk)->sk_lock.slock); \
1351 debug_check_no_locks_freed((void *)&(sk)->sk_lock, \
1352 sizeof((sk)->sk_lock)); \
1353 lockdep_set_class_and_name(&(sk)->sk_lock.slock, \
1354 (skey), (sname)); \
1355 lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \
1356 } while (0)
1357
1358 extern void lock_sock_nested(struct sock *sk, int subclass);
1359
lock_sock(struct sock * sk)1360 static inline void lock_sock(struct sock *sk)
1361 {
1362 lock_sock_nested(sk, 0);
1363 }
1364
1365 extern void release_sock(struct sock *sk);
1366
1367 /* BH context may only use the following locking interface. */
1368 #define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock))
1369 #define bh_lock_sock_nested(__sk) \
1370 spin_lock_nested(&((__sk)->sk_lock.slock), \
1371 SINGLE_DEPTH_NESTING)
1372 #define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock))
1373
1374 extern bool lock_sock_fast(struct sock *sk);
1375 /**
1376 * unlock_sock_fast - complement of lock_sock_fast
1377 * @sk: socket
1378 * @slow: slow mode
1379 *
1380 * fast unlock socket for user context.
1381 * If slow mode is on, we call regular release_sock()
1382 */
unlock_sock_fast(struct sock * sk,bool slow)1383 static inline void unlock_sock_fast(struct sock *sk, bool slow)
1384 {
1385 if (slow)
1386 release_sock(sk);
1387 else
1388 spin_unlock_bh(&sk->sk_lock.slock);
1389 }
1390
1391
1392 extern struct sock *sk_alloc(struct net *net, int family,
1393 gfp_t priority,
1394 struct proto *prot);
1395 extern void sk_free(struct sock *sk);
1396 extern void sk_release_kernel(struct sock *sk);
1397 extern struct sock *sk_clone_lock(const struct sock *sk,
1398 const gfp_t priority);
1399
1400 extern struct sk_buff *sock_wmalloc(struct sock *sk,
1401 unsigned long size, int force,
1402 gfp_t priority);
1403 extern struct sk_buff *sock_rmalloc(struct sock *sk,
1404 unsigned long size, int force,
1405 gfp_t priority);
1406 extern void sock_wfree(struct sk_buff *skb);
1407 extern void sock_rfree(struct sk_buff *skb);
1408
1409 extern int sock_setsockopt(struct socket *sock, int level,
1410 int op, char __user *optval,
1411 unsigned int optlen);
1412
1413 extern int sock_getsockopt(struct socket *sock, int level,
1414 int op, char __user *optval,
1415 int __user *optlen);
1416 extern struct sk_buff *sock_alloc_send_skb(struct sock *sk,
1417 unsigned long size,
1418 int noblock,
1419 int *errcode);
1420 extern struct sk_buff *sock_alloc_send_pskb(struct sock *sk,
1421 unsigned long header_len,
1422 unsigned long data_len,
1423 int noblock,
1424 int *errcode);
1425 extern void *sock_kmalloc(struct sock *sk, int size,
1426 gfp_t priority);
1427 extern void sock_kfree_s(struct sock *sk, void *mem, int size);
1428 extern void sk_send_sigurg(struct sock *sk);
1429
1430 #ifdef CONFIG_CGROUPS
1431 extern void sock_update_classid(struct sock *sk);
1432 #else
sock_update_classid(struct sock * sk)1433 static inline void sock_update_classid(struct sock *sk)
1434 {
1435 }
1436 #endif
1437
1438 /*
1439 * Functions to fill in entries in struct proto_ops when a protocol
1440 * does not implement a particular function.
1441 */
1442 extern int sock_no_bind(struct socket *,
1443 struct sockaddr *, int);
1444 extern int sock_no_connect(struct socket *,
1445 struct sockaddr *, int, int);
1446 extern int sock_no_socketpair(struct socket *,
1447 struct socket *);
1448 extern int sock_no_accept(struct socket *,
1449 struct socket *, int);
1450 extern int sock_no_getname(struct socket *,
1451 struct sockaddr *, int *, int);
1452 extern unsigned int sock_no_poll(struct file *, struct socket *,
1453 struct poll_table_struct *);
1454 extern int sock_no_ioctl(struct socket *, unsigned int,
1455 unsigned long);
1456 extern int sock_no_listen(struct socket *, int);
1457 extern int sock_no_shutdown(struct socket *, int);
1458 extern int sock_no_getsockopt(struct socket *, int , int,
1459 char __user *, int __user *);
1460 extern int sock_no_setsockopt(struct socket *, int, int,
1461 char __user *, unsigned int);
1462 extern int sock_no_sendmsg(struct kiocb *, struct socket *,
1463 struct msghdr *, size_t);
1464 extern int sock_no_recvmsg(struct kiocb *, struct socket *,
1465 struct msghdr *, size_t, int);
1466 extern int sock_no_mmap(struct file *file,
1467 struct socket *sock,
1468 struct vm_area_struct *vma);
1469 extern ssize_t sock_no_sendpage(struct socket *sock,
1470 struct page *page,
1471 int offset, size_t size,
1472 int flags);
1473
1474 /*
1475 * Functions to fill in entries in struct proto_ops when a protocol
1476 * uses the inet style.
1477 */
1478 extern int sock_common_getsockopt(struct socket *sock, int level, int optname,
1479 char __user *optval, int __user *optlen);
1480 extern int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock,
1481 struct msghdr *msg, size_t size, int flags);
1482 extern int sock_common_setsockopt(struct socket *sock, int level, int optname,
1483 char __user *optval, unsigned int optlen);
1484 extern int compat_sock_common_getsockopt(struct socket *sock, int level,
1485 int optname, char __user *optval, int __user *optlen);
1486 extern int compat_sock_common_setsockopt(struct socket *sock, int level,
1487 int optname, char __user *optval, unsigned int optlen);
1488
1489 extern void sk_common_release(struct sock *sk);
1490
1491 /*
1492 * Default socket callbacks and setup code
1493 */
1494
1495 /* Initialise core socket variables */
1496 extern void sock_init_data(struct socket *sock, struct sock *sk);
1497
1498 extern void sk_filter_release_rcu(struct rcu_head *rcu);
1499
1500 /**
1501 * sk_filter_release - release a socket filter
1502 * @fp: filter to remove
1503 *
1504 * Remove a filter from a socket and release its resources.
1505 */
1506
sk_filter_release(struct sk_filter * fp)1507 static inline void sk_filter_release(struct sk_filter *fp)
1508 {
1509 if (atomic_dec_and_test(&fp->refcnt))
1510 call_rcu(&fp->rcu, sk_filter_release_rcu);
1511 }
1512
sk_filter_uncharge(struct sock * sk,struct sk_filter * fp)1513 static inline void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp)
1514 {
1515 unsigned int size = sk_filter_len(fp);
1516
1517 atomic_sub(size, &sk->sk_omem_alloc);
1518 sk_filter_release(fp);
1519 }
1520
sk_filter_charge(struct sock * sk,struct sk_filter * fp)1521 static inline void sk_filter_charge(struct sock *sk, struct sk_filter *fp)
1522 {
1523 atomic_inc(&fp->refcnt);
1524 atomic_add(sk_filter_len(fp), &sk->sk_omem_alloc);
1525 }
1526
1527 /*
1528 * Socket reference counting postulates.
1529 *
1530 * * Each user of socket SHOULD hold a reference count.
1531 * * Each access point to socket (an hash table bucket, reference from a list,
1532 * running timer, skb in flight MUST hold a reference count.
1533 * * When reference count hits 0, it means it will never increase back.
1534 * * When reference count hits 0, it means that no references from
1535 * outside exist to this socket and current process on current CPU
1536 * is last user and may/should destroy this socket.
1537 * * sk_free is called from any context: process, BH, IRQ. When
1538 * it is called, socket has no references from outside -> sk_free
1539 * may release descendant resources allocated by the socket, but
1540 * to the time when it is called, socket is NOT referenced by any
1541 * hash tables, lists etc.
1542 * * Packets, delivered from outside (from network or from another process)
1543 * and enqueued on receive/error queues SHOULD NOT grab reference count,
1544 * when they sit in queue. Otherwise, packets will leak to hole, when
1545 * socket is looked up by one cpu and unhasing is made by another CPU.
1546 * It is true for udp/raw, netlink (leak to receive and error queues), tcp
1547 * (leak to backlog). Packet socket does all the processing inside
1548 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
1549 * use separate SMP lock, so that they are prone too.
1550 */
1551
1552 /* Ungrab socket and destroy it, if it was the last reference. */
sock_put(struct sock * sk)1553 static inline void sock_put(struct sock *sk)
1554 {
1555 if (atomic_dec_and_test(&sk->sk_refcnt))
1556 sk_free(sk);
1557 }
1558
1559 extern int sk_receive_skb(struct sock *sk, struct sk_buff *skb,
1560 const int nested);
1561
sk_tx_queue_set(struct sock * sk,int tx_queue)1562 static inline void sk_tx_queue_set(struct sock *sk, int tx_queue)
1563 {
1564 sk->sk_tx_queue_mapping = tx_queue;
1565 }
1566
sk_tx_queue_clear(struct sock * sk)1567 static inline void sk_tx_queue_clear(struct sock *sk)
1568 {
1569 sk->sk_tx_queue_mapping = -1;
1570 }
1571
sk_tx_queue_get(const struct sock * sk)1572 static inline int sk_tx_queue_get(const struct sock *sk)
1573 {
1574 return sk ? sk->sk_tx_queue_mapping : -1;
1575 }
1576
sk_set_socket(struct sock * sk,struct socket * sock)1577 static inline void sk_set_socket(struct sock *sk, struct socket *sock)
1578 {
1579 sk_tx_queue_clear(sk);
1580 sk->sk_socket = sock;
1581 }
1582
sk_sleep(struct sock * sk)1583 static inline wait_queue_head_t *sk_sleep(struct sock *sk)
1584 {
1585 BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0);
1586 return &rcu_dereference_raw(sk->sk_wq)->wait;
1587 }
1588 /* Detach socket from process context.
1589 * Announce socket dead, detach it from wait queue and inode.
1590 * Note that parent inode held reference count on this struct sock,
1591 * we do not release it in this function, because protocol
1592 * probably wants some additional cleanups or even continuing
1593 * to work with this socket (TCP).
1594 */
sock_orphan(struct sock * sk)1595 static inline void sock_orphan(struct sock *sk)
1596 {
1597 write_lock_bh(&sk->sk_callback_lock);
1598 sock_set_flag(sk, SOCK_DEAD);
1599 sk_set_socket(sk, NULL);
1600 sk->sk_wq = NULL;
1601 write_unlock_bh(&sk->sk_callback_lock);
1602 }
1603
sock_graft(struct sock * sk,struct socket * parent)1604 static inline void sock_graft(struct sock *sk, struct socket *parent)
1605 {
1606 write_lock_bh(&sk->sk_callback_lock);
1607 sk->sk_wq = parent->wq;
1608 parent->sk = sk;
1609 sk_set_socket(sk, parent);
1610 security_sock_graft(sk, parent);
1611 write_unlock_bh(&sk->sk_callback_lock);
1612 }
1613
1614 extern int sock_i_uid(struct sock *sk);
1615 extern unsigned long sock_i_ino(struct sock *sk);
1616
1617 static inline struct dst_entry *
__sk_dst_get(struct sock * sk)1618 __sk_dst_get(struct sock *sk)
1619 {
1620 return rcu_dereference_check(sk->sk_dst_cache, sock_owned_by_user(sk) ||
1621 lockdep_is_held(&sk->sk_lock.slock));
1622 }
1623
1624 static inline struct dst_entry *
sk_dst_get(struct sock * sk)1625 sk_dst_get(struct sock *sk)
1626 {
1627 struct dst_entry *dst;
1628
1629 rcu_read_lock();
1630 dst = rcu_dereference(sk->sk_dst_cache);
1631 if (dst)
1632 dst_hold(dst);
1633 rcu_read_unlock();
1634 return dst;
1635 }
1636
1637 extern void sk_reset_txq(struct sock *sk);
1638
dst_negative_advice(struct sock * sk)1639 static inline void dst_negative_advice(struct sock *sk)
1640 {
1641 struct dst_entry *ndst, *dst = __sk_dst_get(sk);
1642
1643 if (dst && dst->ops->negative_advice) {
1644 ndst = dst->ops->negative_advice(dst);
1645
1646 if (ndst != dst) {
1647 rcu_assign_pointer(sk->sk_dst_cache, ndst);
1648 sk_reset_txq(sk);
1649 }
1650 }
1651 }
1652
1653 static inline void
__sk_dst_set(struct sock * sk,struct dst_entry * dst)1654 __sk_dst_set(struct sock *sk, struct dst_entry *dst)
1655 {
1656 struct dst_entry *old_dst;
1657
1658 sk_tx_queue_clear(sk);
1659 /*
1660 * This can be called while sk is owned by the caller only,
1661 * with no state that can be checked in a rcu_dereference_check() cond
1662 */
1663 old_dst = rcu_dereference_raw(sk->sk_dst_cache);
1664 rcu_assign_pointer(sk->sk_dst_cache, dst);
1665 dst_release(old_dst);
1666 }
1667
1668 static inline void
sk_dst_set(struct sock * sk,struct dst_entry * dst)1669 sk_dst_set(struct sock *sk, struct dst_entry *dst)
1670 {
1671 spin_lock(&sk->sk_dst_lock);
1672 __sk_dst_set(sk, dst);
1673 spin_unlock(&sk->sk_dst_lock);
1674 }
1675
1676 static inline void
__sk_dst_reset(struct sock * sk)1677 __sk_dst_reset(struct sock *sk)
1678 {
1679 __sk_dst_set(sk, NULL);
1680 }
1681
1682 static inline void
sk_dst_reset(struct sock * sk)1683 sk_dst_reset(struct sock *sk)
1684 {
1685 spin_lock(&sk->sk_dst_lock);
1686 __sk_dst_reset(sk);
1687 spin_unlock(&sk->sk_dst_lock);
1688 }
1689
1690 extern struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
1691
1692 extern struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
1693
sk_can_gso(const struct sock * sk)1694 static inline int sk_can_gso(const struct sock *sk)
1695 {
1696 return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type);
1697 }
1698
1699 extern void sk_setup_caps(struct sock *sk, struct dst_entry *dst);
1700
sk_nocaps_add(struct sock * sk,netdev_features_t flags)1701 static inline void sk_nocaps_add(struct sock *sk, netdev_features_t flags)
1702 {
1703 sk->sk_route_nocaps |= flags;
1704 sk->sk_route_caps &= ~flags;
1705 }
1706
skb_do_copy_data_nocache(struct sock * sk,struct sk_buff * skb,char __user * from,char * to,int copy,int offset)1707 static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
1708 char __user *from, char *to,
1709 int copy, int offset)
1710 {
1711 if (skb->ip_summed == CHECKSUM_NONE) {
1712 int err = 0;
1713 __wsum csum = csum_and_copy_from_user(from, to, copy, 0, &err);
1714 if (err)
1715 return err;
1716 skb->csum = csum_block_add(skb->csum, csum, offset);
1717 } else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
1718 if (!access_ok(VERIFY_READ, from, copy) ||
1719 __copy_from_user_nocache(to, from, copy))
1720 return -EFAULT;
1721 } else if (copy_from_user(to, from, copy))
1722 return -EFAULT;
1723
1724 return 0;
1725 }
1726
skb_add_data_nocache(struct sock * sk,struct sk_buff * skb,char __user * from,int copy)1727 static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
1728 char __user *from, int copy)
1729 {
1730 int err, offset = skb->len;
1731
1732 err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy),
1733 copy, offset);
1734 if (err)
1735 __skb_trim(skb, offset);
1736
1737 return err;
1738 }
1739
skb_copy_to_page_nocache(struct sock * sk,char __user * from,struct sk_buff * skb,struct page * page,int off,int copy)1740 static inline int skb_copy_to_page_nocache(struct sock *sk, char __user *from,
1741 struct sk_buff *skb,
1742 struct page *page,
1743 int off, int copy)
1744 {
1745 int err;
1746
1747 err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off,
1748 copy, skb->len);
1749 if (err)
1750 return err;
1751
1752 skb->len += copy;
1753 skb->data_len += copy;
1754 skb->truesize += copy;
1755 sk->sk_wmem_queued += copy;
1756 sk_mem_charge(sk, copy);
1757 return 0;
1758 }
1759
skb_copy_to_page(struct sock * sk,char __user * from,struct sk_buff * skb,struct page * page,int off,int copy)1760 static inline int skb_copy_to_page(struct sock *sk, char __user *from,
1761 struct sk_buff *skb, struct page *page,
1762 int off, int copy)
1763 {
1764 if (skb->ip_summed == CHECKSUM_NONE) {
1765 int err = 0;
1766 __wsum csum = csum_and_copy_from_user(from,
1767 page_address(page) + off,
1768 copy, 0, &err);
1769 if (err)
1770 return err;
1771 skb->csum = csum_block_add(skb->csum, csum, skb->len);
1772 } else if (copy_from_user(page_address(page) + off, from, copy))
1773 return -EFAULT;
1774
1775 skb->len += copy;
1776 skb->data_len += copy;
1777 skb->truesize += copy;
1778 sk->sk_wmem_queued += copy;
1779 sk_mem_charge(sk, copy);
1780 return 0;
1781 }
1782
1783 /**
1784 * sk_wmem_alloc_get - returns write allocations
1785 * @sk: socket
1786 *
1787 * Returns sk_wmem_alloc minus initial offset of one
1788 */
sk_wmem_alloc_get(const struct sock * sk)1789 static inline int sk_wmem_alloc_get(const struct sock *sk)
1790 {
1791 return atomic_read(&sk->sk_wmem_alloc) - 1;
1792 }
1793
1794 /**
1795 * sk_rmem_alloc_get - returns read allocations
1796 * @sk: socket
1797 *
1798 * Returns sk_rmem_alloc
1799 */
sk_rmem_alloc_get(const struct sock * sk)1800 static inline int sk_rmem_alloc_get(const struct sock *sk)
1801 {
1802 return atomic_read(&sk->sk_rmem_alloc);
1803 }
1804
1805 /**
1806 * sk_has_allocations - check if allocations are outstanding
1807 * @sk: socket
1808 *
1809 * Returns true if socket has write or read allocations
1810 */
sk_has_allocations(const struct sock * sk)1811 static inline int sk_has_allocations(const struct sock *sk)
1812 {
1813 return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk);
1814 }
1815
1816 /**
1817 * wq_has_sleeper - check if there are any waiting processes
1818 * @wq: struct socket_wq
1819 *
1820 * Returns true if socket_wq has waiting processes
1821 *
1822 * The purpose of the wq_has_sleeper and sock_poll_wait is to wrap the memory
1823 * barrier call. They were added due to the race found within the tcp code.
1824 *
1825 * Consider following tcp code paths:
1826 *
1827 * CPU1 CPU2
1828 *
1829 * sys_select receive packet
1830 * ... ...
1831 * __add_wait_queue update tp->rcv_nxt
1832 * ... ...
1833 * tp->rcv_nxt check sock_def_readable
1834 * ... {
1835 * schedule rcu_read_lock();
1836 * wq = rcu_dereference(sk->sk_wq);
1837 * if (wq && waitqueue_active(&wq->wait))
1838 * wake_up_interruptible(&wq->wait)
1839 * ...
1840 * }
1841 *
1842 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
1843 * in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1
1844 * could then endup calling schedule and sleep forever if there are no more
1845 * data on the socket.
1846 *
1847 */
wq_has_sleeper(struct socket_wq * wq)1848 static inline bool wq_has_sleeper(struct socket_wq *wq)
1849 {
1850
1851 /*
1852 * We need to be sure we are in sync with the
1853 * add_wait_queue modifications to the wait queue.
1854 *
1855 * This memory barrier is paired in the sock_poll_wait.
1856 */
1857 smp_mb();
1858 return wq && waitqueue_active(&wq->wait);
1859 }
1860
1861 /**
1862 * sock_poll_wait - place memory barrier behind the poll_wait call.
1863 * @filp: file
1864 * @wait_address: socket wait queue
1865 * @p: poll_table
1866 *
1867 * See the comments in the wq_has_sleeper function.
1868 */
sock_poll_wait(struct file * filp,wait_queue_head_t * wait_address,poll_table * p)1869 static inline void sock_poll_wait(struct file *filp,
1870 wait_queue_head_t *wait_address, poll_table *p)
1871 {
1872 if (!poll_does_not_wait(p) && wait_address) {
1873 poll_wait(filp, wait_address, p);
1874 /*
1875 * We need to be sure we are in sync with the
1876 * socket flags modification.
1877 *
1878 * This memory barrier is paired in the wq_has_sleeper.
1879 */
1880 smp_mb();
1881 }
1882 }
1883
1884 /*
1885 * Queue a received datagram if it will fit. Stream and sequenced
1886 * protocols can't normally use this as they need to fit buffers in
1887 * and play with them.
1888 *
1889 * Inlined as it's very short and called for pretty much every
1890 * packet ever received.
1891 */
1892
skb_set_owner_w(struct sk_buff * skb,struct sock * sk)1893 static inline void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
1894 {
1895 skb_orphan(skb);
1896 skb->sk = sk;
1897 skb->destructor = sock_wfree;
1898 /*
1899 * We used to take a refcount on sk, but following operation
1900 * is enough to guarantee sk_free() wont free this sock until
1901 * all in-flight packets are completed
1902 */
1903 atomic_add(skb->truesize, &sk->sk_wmem_alloc);
1904 }
1905
skb_set_owner_r(struct sk_buff * skb,struct sock * sk)1906 static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
1907 {
1908 skb_orphan(skb);
1909 skb->sk = sk;
1910 skb->destructor = sock_rfree;
1911 atomic_add(skb->truesize, &sk->sk_rmem_alloc);
1912 sk_mem_charge(sk, skb->truesize);
1913 }
1914
1915 extern void sk_reset_timer(struct sock *sk, struct timer_list* timer,
1916 unsigned long expires);
1917
1918 extern void sk_stop_timer(struct sock *sk, struct timer_list* timer);
1919
1920 extern int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
1921
1922 extern int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
1923
1924 /*
1925 * Recover an error report and clear atomically
1926 */
1927
sock_error(struct sock * sk)1928 static inline int sock_error(struct sock *sk)
1929 {
1930 int err;
1931 if (likely(!sk->sk_err))
1932 return 0;
1933 err = xchg(&sk->sk_err, 0);
1934 return -err;
1935 }
1936
sock_wspace(struct sock * sk)1937 static inline unsigned long sock_wspace(struct sock *sk)
1938 {
1939 int amt = 0;
1940
1941 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
1942 amt = sk->sk_sndbuf - atomic_read(&sk->sk_wmem_alloc);
1943 if (amt < 0)
1944 amt = 0;
1945 }
1946 return amt;
1947 }
1948
sk_wake_async(struct sock * sk,int how,int band)1949 static inline void sk_wake_async(struct sock *sk, int how, int band)
1950 {
1951 if (sock_flag(sk, SOCK_FASYNC))
1952 sock_wake_async(sk->sk_socket, how, band);
1953 }
1954
1955 #define SOCK_MIN_SNDBUF 2048
1956 /*
1957 * Since sk_rmem_alloc sums skb->truesize, even a small frame might need
1958 * sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak
1959 */
1960 #define SOCK_MIN_RCVBUF (2048 + sizeof(struct sk_buff))
1961
sk_stream_moderate_sndbuf(struct sock * sk)1962 static inline void sk_stream_moderate_sndbuf(struct sock *sk)
1963 {
1964 if (!(sk->sk_userlocks & SOCK_SNDBUF_LOCK)) {
1965 sk->sk_sndbuf = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
1966 sk->sk_sndbuf = max(sk->sk_sndbuf, SOCK_MIN_SNDBUF);
1967 }
1968 }
1969
1970 struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp);
1971
sk_stream_alloc_page(struct sock * sk)1972 static inline struct page *sk_stream_alloc_page(struct sock *sk)
1973 {
1974 struct page *page = NULL;
1975
1976 page = alloc_pages(sk->sk_allocation, 0);
1977 if (!page) {
1978 sk_enter_memory_pressure(sk);
1979 sk_stream_moderate_sndbuf(sk);
1980 }
1981 return page;
1982 }
1983
1984 /*
1985 * Default write policy as shown to user space via poll/select/SIGIO
1986 */
sock_writeable(const struct sock * sk)1987 static inline int sock_writeable(const struct sock *sk)
1988 {
1989 return atomic_read(&sk->sk_wmem_alloc) < (sk->sk_sndbuf >> 1);
1990 }
1991
gfp_any(void)1992 static inline gfp_t gfp_any(void)
1993 {
1994 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
1995 }
1996
sock_rcvtimeo(const struct sock * sk,int noblock)1997 static inline long sock_rcvtimeo(const struct sock *sk, int noblock)
1998 {
1999 return noblock ? 0 : sk->sk_rcvtimeo;
2000 }
2001
sock_sndtimeo(const struct sock * sk,int noblock)2002 static inline long sock_sndtimeo(const struct sock *sk, int noblock)
2003 {
2004 return noblock ? 0 : sk->sk_sndtimeo;
2005 }
2006
sock_rcvlowat(const struct sock * sk,int waitall,int len)2007 static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
2008 {
2009 return (waitall ? len : min_t(int, sk->sk_rcvlowat, len)) ? : 1;
2010 }
2011
2012 /* Alas, with timeout socket operations are not restartable.
2013 * Compare this to poll().
2014 */
sock_intr_errno(long timeo)2015 static inline int sock_intr_errno(long timeo)
2016 {
2017 return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
2018 }
2019
2020 extern void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
2021 struct sk_buff *skb);
2022 extern void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
2023 struct sk_buff *skb);
2024
2025 static __inline__ void
sock_recv_timestamp(struct msghdr * msg,struct sock * sk,struct sk_buff * skb)2026 sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
2027 {
2028 ktime_t kt = skb->tstamp;
2029 struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
2030
2031 /*
2032 * generate control messages if
2033 * - receive time stamping in software requested (SOCK_RCVTSTAMP
2034 * or SOCK_TIMESTAMPING_RX_SOFTWARE)
2035 * - software time stamp available and wanted
2036 * (SOCK_TIMESTAMPING_SOFTWARE)
2037 * - hardware time stamps available and wanted
2038 * (SOCK_TIMESTAMPING_SYS_HARDWARE or
2039 * SOCK_TIMESTAMPING_RAW_HARDWARE)
2040 */
2041 if (sock_flag(sk, SOCK_RCVTSTAMP) ||
2042 sock_flag(sk, SOCK_TIMESTAMPING_RX_SOFTWARE) ||
2043 (kt.tv64 && sock_flag(sk, SOCK_TIMESTAMPING_SOFTWARE)) ||
2044 (hwtstamps->hwtstamp.tv64 &&
2045 sock_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE)) ||
2046 (hwtstamps->syststamp.tv64 &&
2047 sock_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE)))
2048 __sock_recv_timestamp(msg, sk, skb);
2049 else
2050 sk->sk_stamp = kt;
2051
2052 if (sock_flag(sk, SOCK_WIFI_STATUS) && skb->wifi_acked_valid)
2053 __sock_recv_wifi_status(msg, sk, skb);
2054 }
2055
2056 extern void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2057 struct sk_buff *skb);
2058
sock_recv_ts_and_drops(struct msghdr * msg,struct sock * sk,struct sk_buff * skb)2059 static inline void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2060 struct sk_buff *skb)
2061 {
2062 #define FLAGS_TS_OR_DROPS ((1UL << SOCK_RXQ_OVFL) | \
2063 (1UL << SOCK_RCVTSTAMP) | \
2064 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE) | \
2065 (1UL << SOCK_TIMESTAMPING_SOFTWARE) | \
2066 (1UL << SOCK_TIMESTAMPING_RAW_HARDWARE) | \
2067 (1UL << SOCK_TIMESTAMPING_SYS_HARDWARE))
2068
2069 if (sk->sk_flags & FLAGS_TS_OR_DROPS)
2070 __sock_recv_ts_and_drops(msg, sk, skb);
2071 else
2072 sk->sk_stamp = skb->tstamp;
2073 }
2074
2075 /**
2076 * sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
2077 * @sk: socket sending this packet
2078 * @tx_flags: filled with instructions for time stamping
2079 *
2080 * Currently only depends on SOCK_TIMESTAMPING* flags. Returns error code if
2081 * parameters are invalid.
2082 */
2083 extern int sock_tx_timestamp(struct sock *sk, __u8 *tx_flags);
2084
2085 /**
2086 * sk_eat_skb - Release a skb if it is no longer needed
2087 * @sk: socket to eat this skb from
2088 * @skb: socket buffer to eat
2089 * @copied_early: flag indicating whether DMA operations copied this data early
2090 *
2091 * This routine must be called with interrupts disabled or with the socket
2092 * locked so that the sk_buff queue operation is ok.
2093 */
2094 #ifdef CONFIG_NET_DMA
sk_eat_skb(struct sock * sk,struct sk_buff * skb,int copied_early)2095 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb, int copied_early)
2096 {
2097 __skb_unlink(skb, &sk->sk_receive_queue);
2098 if (!copied_early)
2099 __kfree_skb(skb);
2100 else
2101 __skb_queue_tail(&sk->sk_async_wait_queue, skb);
2102 }
2103 #else
sk_eat_skb(struct sock * sk,struct sk_buff * skb,int copied_early)2104 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb, int copied_early)
2105 {
2106 __skb_unlink(skb, &sk->sk_receive_queue);
2107 __kfree_skb(skb);
2108 }
2109 #endif
2110
2111 static inline
sock_net(const struct sock * sk)2112 struct net *sock_net(const struct sock *sk)
2113 {
2114 return read_pnet(&sk->sk_net);
2115 }
2116
2117 static inline
sock_net_set(struct sock * sk,struct net * net)2118 void sock_net_set(struct sock *sk, struct net *net)
2119 {
2120 write_pnet(&sk->sk_net, net);
2121 }
2122
2123 /*
2124 * Kernel sockets, f.e. rtnl or icmp_socket, are a part of a namespace.
2125 * They should not hold a reference to a namespace in order to allow
2126 * to stop it.
2127 * Sockets after sk_change_net should be released using sk_release_kernel
2128 */
sk_change_net(struct sock * sk,struct net * net)2129 static inline void sk_change_net(struct sock *sk, struct net *net)
2130 {
2131 put_net(sock_net(sk));
2132 sock_net_set(sk, hold_net(net));
2133 }
2134
skb_steal_sock(struct sk_buff * skb)2135 static inline struct sock *skb_steal_sock(struct sk_buff *skb)
2136 {
2137 if (unlikely(skb->sk)) {
2138 struct sock *sk = skb->sk;
2139
2140 skb->destructor = NULL;
2141 skb->sk = NULL;
2142 return sk;
2143 }
2144 return NULL;
2145 }
2146
2147 extern void sock_enable_timestamp(struct sock *sk, int flag);
2148 extern int sock_get_timestamp(struct sock *, struct timeval __user *);
2149 extern int sock_get_timestampns(struct sock *, struct timespec __user *);
2150
2151 /*
2152 * Enable debug/info messages
2153 */
2154 extern int net_msg_warn;
2155 #define NETDEBUG(fmt, args...) \
2156 do { if (net_msg_warn) printk(fmt,##args); } while (0)
2157
2158 #define LIMIT_NETDEBUG(fmt, args...) \
2159 do { if (net_msg_warn && net_ratelimit()) printk(fmt,##args); } while(0)
2160
2161 extern __u32 sysctl_wmem_max;
2162 extern __u32 sysctl_rmem_max;
2163
2164 extern void sk_init(void);
2165
2166 extern int sysctl_optmem_max;
2167
2168 extern __u32 sysctl_wmem_default;
2169 extern __u32 sysctl_rmem_default;
2170
2171 #endif /* _SOCK_H */
2172