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/kernel.h> 44 #include <linux/list.h> 45 #include <linux/list_nulls.h> 46 #include <linux/timer.h> 47 #include <linux/cache.h> 48 #include <linux/module.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 55 #include <linux/filter.h> 56 #include <linux/rculist_nulls.h> 57 58 #include <asm/atomic.h> 59 #include <net/dst.h> 60 #include <net/checksum.h> 61 62 /* 63 * This structure really needs to be cleaned up. 64 * Most of it is for TCP, and not used by any of 65 * the other protocols. 66 */ 67 68 /* Define this to get the SOCK_DBG debugging facility. */ 69 #define SOCK_DEBUGGING 70 #ifdef SOCK_DEBUGGING 71 #define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \ 72 printk(KERN_DEBUG msg); } while (0) 73 #else 74 /* Validate arguments and do nothing */ 75 static void inline int __attribute__ ((format (printf, 2, 3))) 76 SOCK_DEBUG(struct sock *sk, const char *msg, ...) 77 { 78 } 79 #endif 80 81 /* This is the per-socket lock. The spinlock provides a synchronization 82 * between user contexts and software interrupt processing, whereas the 83 * mini-semaphore synchronizes multiple users amongst themselves. 84 */ 85 typedef struct { 86 spinlock_t slock; 87 int owned; 88 wait_queue_head_t wq; 89 /* 90 * We express the mutex-alike socket_lock semantics 91 * to the lock validator by explicitly managing 92 * the slock as a lock variant (in addition to 93 * the slock itself): 94 */ 95 #ifdef CONFIG_DEBUG_LOCK_ALLOC 96 struct lockdep_map dep_map; 97 #endif 98 } socket_lock_t; 99 100 struct sock; 101 struct proto; 102 struct net; 103 104 /** 105 * struct sock_common - minimal network layer representation of sockets 106 * @skc_family: network address family 107 * @skc_state: Connection state 108 * @skc_reuse: %SO_REUSEADDR setting 109 * @skc_bound_dev_if: bound device index if != 0 110 * @skc_node: main hash linkage for various protocol lookup tables 111 * @skc_nulls_node: main hash linkage for UDP/UDP-Lite protocol 112 * @skc_bind_node: bind hash linkage for various protocol lookup tables 113 * @skc_refcnt: reference count 114 * @skc_hash: hash value used with various protocol lookup tables 115 * @skc_prot: protocol handlers inside a network family 116 * @skc_net: reference to the network namespace of this socket 117 * 118 * This is the minimal network layer representation of sockets, the header 119 * for struct sock and struct inet_timewait_sock. 120 */ 121 struct sock_common { 122 unsigned short skc_family; 123 volatile unsigned char skc_state; 124 unsigned char skc_reuse; 125 int skc_bound_dev_if; 126 union { 127 struct hlist_node skc_node; 128 struct hlist_nulls_node skc_nulls_node; 129 }; 130 struct hlist_node skc_bind_node; 131 atomic_t skc_refcnt; 132 unsigned int skc_hash; 133 struct proto *skc_prot; 134 #ifdef CONFIG_NET_NS 135 struct net *skc_net; 136 #endif 137 }; 138 139 /** 140 * struct sock - network layer representation of sockets 141 * @__sk_common: shared layout with inet_timewait_sock 142 * @sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN 143 * @sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings 144 * @sk_lock: synchronizer 145 * @sk_rcvbuf: size of receive buffer in bytes 146 * @sk_sleep: sock wait queue 147 * @sk_dst_cache: destination cache 148 * @sk_dst_lock: destination cache lock 149 * @sk_policy: flow policy 150 * @sk_rmem_alloc: receive queue bytes committed 151 * @sk_receive_queue: incoming packets 152 * @sk_wmem_alloc: transmit queue bytes committed 153 * @sk_write_queue: Packet sending queue 154 * @sk_async_wait_queue: DMA copied packets 155 * @sk_omem_alloc: "o" is "option" or "other" 156 * @sk_wmem_queued: persistent queue size 157 * @sk_forward_alloc: space allocated forward 158 * @sk_allocation: allocation mode 159 * @sk_sndbuf: size of send buffer in bytes 160 * @sk_flags: %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE, 161 * %SO_OOBINLINE settings 162 * @sk_no_check: %SO_NO_CHECK setting, wether or not checkup packets 163 * @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO) 164 * @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4) 165 * @sk_gso_max_size: Maximum GSO segment size to build 166 * @sk_lingertime: %SO_LINGER l_linger setting 167 * @sk_backlog: always used with the per-socket spinlock held 168 * @sk_callback_lock: used with the callbacks in the end of this struct 169 * @sk_error_queue: rarely used 170 * @sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt, 171 * IPV6_ADDRFORM for instance) 172 * @sk_err: last error 173 * @sk_err_soft: errors that don't cause failure but are the cause of a 174 * persistent failure not just 'timed out' 175 * @sk_drops: raw/udp drops counter 176 * @sk_ack_backlog: current listen backlog 177 * @sk_max_ack_backlog: listen backlog set in listen() 178 * @sk_priority: %SO_PRIORITY setting 179 * @sk_type: socket type (%SOCK_STREAM, etc) 180 * @sk_protocol: which protocol this socket belongs in this network family 181 * @sk_peercred: %SO_PEERCRED setting 182 * @sk_rcvlowat: %SO_RCVLOWAT setting 183 * @sk_rcvtimeo: %SO_RCVTIMEO setting 184 * @sk_sndtimeo: %SO_SNDTIMEO setting 185 * @sk_filter: socket filtering instructions 186 * @sk_protinfo: private area, net family specific, when not using slab 187 * @sk_timer: sock cleanup timer 188 * @sk_stamp: time stamp of last packet received 189 * @sk_socket: Identd and reporting IO signals 190 * @sk_user_data: RPC layer private data 191 * @sk_sndmsg_page: cached page for sendmsg 192 * @sk_sndmsg_off: cached offset for sendmsg 193 * @sk_send_head: front of stuff to transmit 194 * @sk_security: used by security modules 195 * @sk_mark: generic packet mark 196 * @sk_write_pending: a write to stream socket waits to start 197 * @sk_state_change: callback to indicate change in the state of the sock 198 * @sk_data_ready: callback to indicate there is data to be processed 199 * @sk_write_space: callback to indicate there is bf sending space available 200 * @sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE) 201 * @sk_backlog_rcv: callback to process the backlog 202 * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0 203 */ 204 struct sock { 205 /* 206 * Now struct inet_timewait_sock also uses sock_common, so please just 207 * don't add nothing before this first member (__sk_common) --acme 208 */ 209 struct sock_common __sk_common; 210 #define sk_family __sk_common.skc_family 211 #define sk_state __sk_common.skc_state 212 #define sk_reuse __sk_common.skc_reuse 213 #define sk_bound_dev_if __sk_common.skc_bound_dev_if 214 #define sk_node __sk_common.skc_node 215 #define sk_nulls_node __sk_common.skc_nulls_node 216 #define sk_bind_node __sk_common.skc_bind_node 217 #define sk_refcnt __sk_common.skc_refcnt 218 #define sk_hash __sk_common.skc_hash 219 #define sk_prot __sk_common.skc_prot 220 #define sk_net __sk_common.skc_net 221 unsigned char sk_shutdown : 2, 222 sk_no_check : 2, 223 sk_userlocks : 4; 224 unsigned char sk_protocol; 225 unsigned short sk_type; 226 int sk_rcvbuf; 227 socket_lock_t sk_lock; 228 /* 229 * The backlog queue is special, it is always used with 230 * the per-socket spinlock held and requires low latency 231 * access. Therefore we special case it's implementation. 232 */ 233 struct { 234 struct sk_buff *head; 235 struct sk_buff *tail; 236 } sk_backlog; 237 wait_queue_head_t *sk_sleep; 238 struct dst_entry *sk_dst_cache; 239 #ifdef CONFIG_XFRM 240 struct xfrm_policy *sk_policy[2]; 241 #endif 242 rwlock_t sk_dst_lock; 243 atomic_t sk_rmem_alloc; 244 atomic_t sk_wmem_alloc; 245 atomic_t sk_omem_alloc; 246 int sk_sndbuf; 247 struct sk_buff_head sk_receive_queue; 248 struct sk_buff_head sk_write_queue; 249 #ifdef CONFIG_NET_DMA 250 struct sk_buff_head sk_async_wait_queue; 251 #endif 252 int sk_wmem_queued; 253 int sk_forward_alloc; 254 gfp_t sk_allocation; 255 int sk_route_caps; 256 int sk_gso_type; 257 unsigned int sk_gso_max_size; 258 int sk_rcvlowat; 259 unsigned long sk_flags; 260 unsigned long sk_lingertime; 261 struct sk_buff_head sk_error_queue; 262 struct proto *sk_prot_creator; 263 rwlock_t sk_callback_lock; 264 int sk_err, 265 sk_err_soft; 266 atomic_t sk_drops; 267 unsigned short sk_ack_backlog; 268 unsigned short sk_max_ack_backlog; 269 __u32 sk_priority; 270 struct ucred sk_peercred; 271 long sk_rcvtimeo; 272 long sk_sndtimeo; 273 struct sk_filter *sk_filter; 274 void *sk_protinfo; 275 struct timer_list sk_timer; 276 ktime_t sk_stamp; 277 struct socket *sk_socket; 278 void *sk_user_data; 279 struct page *sk_sndmsg_page; 280 struct sk_buff *sk_send_head; 281 __u32 sk_sndmsg_off; 282 int sk_write_pending; 283 #ifdef CONFIG_SECURITY 284 void *sk_security; 285 #endif 286 __u32 sk_mark; 287 /* XXX 4 bytes hole on 64 bit */ 288 void (*sk_state_change)(struct sock *sk); 289 void (*sk_data_ready)(struct sock *sk, int bytes); 290 void (*sk_write_space)(struct sock *sk); 291 void (*sk_error_report)(struct sock *sk); 292 int (*sk_backlog_rcv)(struct sock *sk, 293 struct sk_buff *skb); 294 void (*sk_destruct)(struct sock *sk); 295 }; 296 297 /* 298 * Hashed lists helper routines 299 */ 300 static inline struct sock *__sk_head(const struct hlist_head *head) 301 { 302 return hlist_entry(head->first, struct sock, sk_node); 303 } 304 305 static inline struct sock *sk_head(const struct hlist_head *head) 306 { 307 return hlist_empty(head) ? NULL : __sk_head(head); 308 } 309 310 static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head) 311 { 312 return hlist_nulls_entry(head->first, struct sock, sk_nulls_node); 313 } 314 315 static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head) 316 { 317 return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head); 318 } 319 320 static inline struct sock *sk_next(const struct sock *sk) 321 { 322 return sk->sk_node.next ? 323 hlist_entry(sk->sk_node.next, struct sock, sk_node) : NULL; 324 } 325 326 static inline struct sock *sk_nulls_next(const struct sock *sk) 327 { 328 return (!is_a_nulls(sk->sk_nulls_node.next)) ? 329 hlist_nulls_entry(sk->sk_nulls_node.next, 330 struct sock, sk_nulls_node) : 331 NULL; 332 } 333 334 static inline int sk_unhashed(const struct sock *sk) 335 { 336 return hlist_unhashed(&sk->sk_node); 337 } 338 339 static inline int sk_hashed(const struct sock *sk) 340 { 341 return !sk_unhashed(sk); 342 } 343 344 static __inline__ void sk_node_init(struct hlist_node *node) 345 { 346 node->pprev = NULL; 347 } 348 349 static __inline__ void sk_nulls_node_init(struct hlist_nulls_node *node) 350 { 351 node->pprev = NULL; 352 } 353 354 static __inline__ void __sk_del_node(struct sock *sk) 355 { 356 __hlist_del(&sk->sk_node); 357 } 358 359 static __inline__ int __sk_del_node_init(struct sock *sk) 360 { 361 if (sk_hashed(sk)) { 362 __sk_del_node(sk); 363 sk_node_init(&sk->sk_node); 364 return 1; 365 } 366 return 0; 367 } 368 369 /* Grab socket reference count. This operation is valid only 370 when sk is ALREADY grabbed f.e. it is found in hash table 371 or a list and the lookup is made under lock preventing hash table 372 modifications. 373 */ 374 375 static inline void sock_hold(struct sock *sk) 376 { 377 atomic_inc(&sk->sk_refcnt); 378 } 379 380 /* Ungrab socket in the context, which assumes that socket refcnt 381 cannot hit zero, f.e. it is true in context of any socketcall. 382 */ 383 static inline void __sock_put(struct sock *sk) 384 { 385 atomic_dec(&sk->sk_refcnt); 386 } 387 388 static __inline__ int sk_del_node_init(struct sock *sk) 389 { 390 int rc = __sk_del_node_init(sk); 391 392 if (rc) { 393 /* paranoid for a while -acme */ 394 WARN_ON(atomic_read(&sk->sk_refcnt) == 1); 395 __sock_put(sk); 396 } 397 return rc; 398 } 399 400 static __inline__ int __sk_nulls_del_node_init_rcu(struct sock *sk) 401 { 402 if (sk_hashed(sk)) { 403 hlist_nulls_del_init_rcu(&sk->sk_nulls_node); 404 return 1; 405 } 406 return 0; 407 } 408 409 static __inline__ int sk_nulls_del_node_init_rcu(struct sock *sk) 410 { 411 int rc = __sk_nulls_del_node_init_rcu(sk); 412 413 if (rc) { 414 /* paranoid for a while -acme */ 415 WARN_ON(atomic_read(&sk->sk_refcnt) == 1); 416 __sock_put(sk); 417 } 418 return rc; 419 } 420 421 static __inline__ void __sk_add_node(struct sock *sk, struct hlist_head *list) 422 { 423 hlist_add_head(&sk->sk_node, list); 424 } 425 426 static __inline__ void sk_add_node(struct sock *sk, struct hlist_head *list) 427 { 428 sock_hold(sk); 429 __sk_add_node(sk, list); 430 } 431 432 static __inline__ void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list) 433 { 434 hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list); 435 } 436 437 static __inline__ void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list) 438 { 439 sock_hold(sk); 440 __sk_nulls_add_node_rcu(sk, list); 441 } 442 443 static __inline__ void __sk_del_bind_node(struct sock *sk) 444 { 445 __hlist_del(&sk->sk_bind_node); 446 } 447 448 static __inline__ void sk_add_bind_node(struct sock *sk, 449 struct hlist_head *list) 450 { 451 hlist_add_head(&sk->sk_bind_node, list); 452 } 453 454 #define sk_for_each(__sk, node, list) \ 455 hlist_for_each_entry(__sk, node, list, sk_node) 456 #define sk_nulls_for_each(__sk, node, list) \ 457 hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node) 458 #define sk_nulls_for_each_rcu(__sk, node, list) \ 459 hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node) 460 #define sk_for_each_from(__sk, node) \ 461 if (__sk && ({ node = &(__sk)->sk_node; 1; })) \ 462 hlist_for_each_entry_from(__sk, node, sk_node) 463 #define sk_nulls_for_each_from(__sk, node) \ 464 if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \ 465 hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node) 466 #define sk_for_each_continue(__sk, node) \ 467 if (__sk && ({ node = &(__sk)->sk_node; 1; })) \ 468 hlist_for_each_entry_continue(__sk, node, sk_node) 469 #define sk_for_each_safe(__sk, node, tmp, list) \ 470 hlist_for_each_entry_safe(__sk, node, tmp, list, sk_node) 471 #define sk_for_each_bound(__sk, node, list) \ 472 hlist_for_each_entry(__sk, node, list, sk_bind_node) 473 474 /* Sock flags */ 475 enum sock_flags { 476 SOCK_DEAD, 477 SOCK_DONE, 478 SOCK_URGINLINE, 479 SOCK_KEEPOPEN, 480 SOCK_LINGER, 481 SOCK_DESTROY, 482 SOCK_BROADCAST, 483 SOCK_TIMESTAMP, 484 SOCK_ZAPPED, 485 SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */ 486 SOCK_DBG, /* %SO_DEBUG setting */ 487 SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */ 488 SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */ 489 SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */ 490 SOCK_QUEUE_SHRUNK, /* write queue has been shrunk recently */ 491 }; 492 493 static inline void sock_copy_flags(struct sock *nsk, struct sock *osk) 494 { 495 nsk->sk_flags = osk->sk_flags; 496 } 497 498 static inline void sock_set_flag(struct sock *sk, enum sock_flags flag) 499 { 500 __set_bit(flag, &sk->sk_flags); 501 } 502 503 static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag) 504 { 505 __clear_bit(flag, &sk->sk_flags); 506 } 507 508 static inline int sock_flag(struct sock *sk, enum sock_flags flag) 509 { 510 return test_bit(flag, &sk->sk_flags); 511 } 512 513 static inline void sk_acceptq_removed(struct sock *sk) 514 { 515 sk->sk_ack_backlog--; 516 } 517 518 static inline void sk_acceptq_added(struct sock *sk) 519 { 520 sk->sk_ack_backlog++; 521 } 522 523 static inline int sk_acceptq_is_full(struct sock *sk) 524 { 525 return sk->sk_ack_backlog > sk->sk_max_ack_backlog; 526 } 527 528 /* 529 * Compute minimal free write space needed to queue new packets. 530 */ 531 static inline int sk_stream_min_wspace(struct sock *sk) 532 { 533 return sk->sk_wmem_queued >> 1; 534 } 535 536 static inline int sk_stream_wspace(struct sock *sk) 537 { 538 return sk->sk_sndbuf - sk->sk_wmem_queued; 539 } 540 541 extern void sk_stream_write_space(struct sock *sk); 542 543 static inline int sk_stream_memory_free(struct sock *sk) 544 { 545 return sk->sk_wmem_queued < sk->sk_sndbuf; 546 } 547 548 /* The per-socket spinlock must be held here. */ 549 static inline void sk_add_backlog(struct sock *sk, struct sk_buff *skb) 550 { 551 if (!sk->sk_backlog.tail) { 552 sk->sk_backlog.head = sk->sk_backlog.tail = skb; 553 } else { 554 sk->sk_backlog.tail->next = skb; 555 sk->sk_backlog.tail = skb; 556 } 557 skb->next = NULL; 558 } 559 560 static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb) 561 { 562 return sk->sk_backlog_rcv(sk, skb); 563 } 564 565 #define sk_wait_event(__sk, __timeo, __condition) \ 566 ({ int __rc; \ 567 release_sock(__sk); \ 568 __rc = __condition; \ 569 if (!__rc) { \ 570 *(__timeo) = schedule_timeout(*(__timeo)); \ 571 } \ 572 lock_sock(__sk); \ 573 __rc = __condition; \ 574 __rc; \ 575 }) 576 577 extern int sk_stream_wait_connect(struct sock *sk, long *timeo_p); 578 extern int sk_stream_wait_memory(struct sock *sk, long *timeo_p); 579 extern void sk_stream_wait_close(struct sock *sk, long timeo_p); 580 extern int sk_stream_error(struct sock *sk, int flags, int err); 581 extern void sk_stream_kill_queues(struct sock *sk); 582 583 extern int sk_wait_data(struct sock *sk, long *timeo); 584 585 struct request_sock_ops; 586 struct timewait_sock_ops; 587 struct inet_hashinfo; 588 struct raw_hashinfo; 589 590 /* Networking protocol blocks we attach to sockets. 591 * socket layer -> transport layer interface 592 * transport -> network interface is defined by struct inet_proto 593 */ 594 struct proto { 595 void (*close)(struct sock *sk, 596 long timeout); 597 int (*connect)(struct sock *sk, 598 struct sockaddr *uaddr, 599 int addr_len); 600 int (*disconnect)(struct sock *sk, int flags); 601 602 struct sock * (*accept) (struct sock *sk, int flags, int *err); 603 604 int (*ioctl)(struct sock *sk, int cmd, 605 unsigned long arg); 606 int (*init)(struct sock *sk); 607 void (*destroy)(struct sock *sk); 608 void (*shutdown)(struct sock *sk, int how); 609 int (*setsockopt)(struct sock *sk, int level, 610 int optname, char __user *optval, 611 int optlen); 612 int (*getsockopt)(struct sock *sk, int level, 613 int optname, char __user *optval, 614 int __user *option); 615 #ifdef CONFIG_COMPAT 616 int (*compat_setsockopt)(struct sock *sk, 617 int level, 618 int optname, char __user *optval, 619 int optlen); 620 int (*compat_getsockopt)(struct sock *sk, 621 int level, 622 int optname, char __user *optval, 623 int __user *option); 624 #endif 625 int (*sendmsg)(struct kiocb *iocb, struct sock *sk, 626 struct msghdr *msg, size_t len); 627 int (*recvmsg)(struct kiocb *iocb, struct sock *sk, 628 struct msghdr *msg, 629 size_t len, int noblock, int flags, 630 int *addr_len); 631 int (*sendpage)(struct sock *sk, struct page *page, 632 int offset, size_t size, int flags); 633 int (*bind)(struct sock *sk, 634 struct sockaddr *uaddr, int addr_len); 635 636 int (*backlog_rcv) (struct sock *sk, 637 struct sk_buff *skb); 638 639 /* Keeping track of sk's, looking them up, and port selection methods. */ 640 void (*hash)(struct sock *sk); 641 void (*unhash)(struct sock *sk); 642 int (*get_port)(struct sock *sk, unsigned short snum); 643 644 /* Keeping track of sockets in use */ 645 #ifdef CONFIG_PROC_FS 646 unsigned int inuse_idx; 647 #endif 648 649 /* Memory pressure */ 650 void (*enter_memory_pressure)(struct sock *sk); 651 atomic_t *memory_allocated; /* Current allocated memory. */ 652 struct percpu_counter *sockets_allocated; /* Current number of sockets. */ 653 /* 654 * Pressure flag: try to collapse. 655 * Technical note: it is used by multiple contexts non atomically. 656 * All the __sk_mem_schedule() is of this nature: accounting 657 * is strict, actions are advisory and have some latency. 658 */ 659 int *memory_pressure; 660 int *sysctl_mem; 661 int *sysctl_wmem; 662 int *sysctl_rmem; 663 int max_header; 664 665 struct kmem_cache *slab; 666 unsigned int obj_size; 667 int slab_flags; 668 669 struct percpu_counter *orphan_count; 670 671 struct request_sock_ops *rsk_prot; 672 struct timewait_sock_ops *twsk_prot; 673 674 union { 675 struct inet_hashinfo *hashinfo; 676 struct udp_table *udp_table; 677 struct raw_hashinfo *raw_hash; 678 } h; 679 680 struct module *owner; 681 682 char name[32]; 683 684 struct list_head node; 685 #ifdef SOCK_REFCNT_DEBUG 686 atomic_t socks; 687 #endif 688 }; 689 690 extern int proto_register(struct proto *prot, int alloc_slab); 691 extern void proto_unregister(struct proto *prot); 692 693 #ifdef SOCK_REFCNT_DEBUG 694 static inline void sk_refcnt_debug_inc(struct sock *sk) 695 { 696 atomic_inc(&sk->sk_prot->socks); 697 } 698 699 static inline void sk_refcnt_debug_dec(struct sock *sk) 700 { 701 atomic_dec(&sk->sk_prot->socks); 702 printk(KERN_DEBUG "%s socket %p released, %d are still alive\n", 703 sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks)); 704 } 705 706 static inline void sk_refcnt_debug_release(const struct sock *sk) 707 { 708 if (atomic_read(&sk->sk_refcnt) != 1) 709 printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n", 710 sk->sk_prot->name, sk, atomic_read(&sk->sk_refcnt)); 711 } 712 #else /* SOCK_REFCNT_DEBUG */ 713 #define sk_refcnt_debug_inc(sk) do { } while (0) 714 #define sk_refcnt_debug_dec(sk) do { } while (0) 715 #define sk_refcnt_debug_release(sk) do { } while (0) 716 #endif /* SOCK_REFCNT_DEBUG */ 717 718 719 #ifdef CONFIG_PROC_FS 720 /* Called with local bh disabled */ 721 extern void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc); 722 extern int sock_prot_inuse_get(struct net *net, struct proto *proto); 723 #else 724 static void inline sock_prot_inuse_add(struct net *net, struct proto *prot, 725 int inc) 726 { 727 } 728 #endif 729 730 731 /* With per-bucket locks this operation is not-atomic, so that 732 * this version is not worse. 733 */ 734 static inline void __sk_prot_rehash(struct sock *sk) 735 { 736 sk->sk_prot->unhash(sk); 737 sk->sk_prot->hash(sk); 738 } 739 740 /* About 10 seconds */ 741 #define SOCK_DESTROY_TIME (10*HZ) 742 743 /* Sockets 0-1023 can't be bound to unless you are superuser */ 744 #define PROT_SOCK 1024 745 746 #define SHUTDOWN_MASK 3 747 #define RCV_SHUTDOWN 1 748 #define SEND_SHUTDOWN 2 749 750 #define SOCK_SNDBUF_LOCK 1 751 #define SOCK_RCVBUF_LOCK 2 752 #define SOCK_BINDADDR_LOCK 4 753 #define SOCK_BINDPORT_LOCK 8 754 755 /* sock_iocb: used to kick off async processing of socket ios */ 756 struct sock_iocb { 757 struct list_head list; 758 759 int flags; 760 int size; 761 struct socket *sock; 762 struct sock *sk; 763 struct scm_cookie *scm; 764 struct msghdr *msg, async_msg; 765 struct kiocb *kiocb; 766 }; 767 768 static inline struct sock_iocb *kiocb_to_siocb(struct kiocb *iocb) 769 { 770 return (struct sock_iocb *)iocb->private; 771 } 772 773 static inline struct kiocb *siocb_to_kiocb(struct sock_iocb *si) 774 { 775 return si->kiocb; 776 } 777 778 struct socket_alloc { 779 struct socket socket; 780 struct inode vfs_inode; 781 }; 782 783 static inline struct socket *SOCKET_I(struct inode *inode) 784 { 785 return &container_of(inode, struct socket_alloc, vfs_inode)->socket; 786 } 787 788 static inline struct inode *SOCK_INODE(struct socket *socket) 789 { 790 return &container_of(socket, struct socket_alloc, socket)->vfs_inode; 791 } 792 793 /* 794 * Functions for memory accounting 795 */ 796 extern int __sk_mem_schedule(struct sock *sk, int size, int kind); 797 extern void __sk_mem_reclaim(struct sock *sk); 798 799 #define SK_MEM_QUANTUM ((int)PAGE_SIZE) 800 #define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM) 801 #define SK_MEM_SEND 0 802 #define SK_MEM_RECV 1 803 804 static inline int sk_mem_pages(int amt) 805 { 806 return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT; 807 } 808 809 static inline int sk_has_account(struct sock *sk) 810 { 811 /* return true if protocol supports memory accounting */ 812 return !!sk->sk_prot->memory_allocated; 813 } 814 815 static inline int sk_wmem_schedule(struct sock *sk, int size) 816 { 817 if (!sk_has_account(sk)) 818 return 1; 819 return size <= sk->sk_forward_alloc || 820 __sk_mem_schedule(sk, size, SK_MEM_SEND); 821 } 822 823 static inline int sk_rmem_schedule(struct sock *sk, int size) 824 { 825 if (!sk_has_account(sk)) 826 return 1; 827 return size <= sk->sk_forward_alloc || 828 __sk_mem_schedule(sk, size, SK_MEM_RECV); 829 } 830 831 static inline void sk_mem_reclaim(struct sock *sk) 832 { 833 if (!sk_has_account(sk)) 834 return; 835 if (sk->sk_forward_alloc >= SK_MEM_QUANTUM) 836 __sk_mem_reclaim(sk); 837 } 838 839 static inline void sk_mem_reclaim_partial(struct sock *sk) 840 { 841 if (!sk_has_account(sk)) 842 return; 843 if (sk->sk_forward_alloc > SK_MEM_QUANTUM) 844 __sk_mem_reclaim(sk); 845 } 846 847 static inline void sk_mem_charge(struct sock *sk, int size) 848 { 849 if (!sk_has_account(sk)) 850 return; 851 sk->sk_forward_alloc -= size; 852 } 853 854 static inline void sk_mem_uncharge(struct sock *sk, int size) 855 { 856 if (!sk_has_account(sk)) 857 return; 858 sk->sk_forward_alloc += size; 859 } 860 861 static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb) 862 { 863 sock_set_flag(sk, SOCK_QUEUE_SHRUNK); 864 sk->sk_wmem_queued -= skb->truesize; 865 sk_mem_uncharge(sk, skb->truesize); 866 __kfree_skb(skb); 867 } 868 869 /* Used by processes to "lock" a socket state, so that 870 * interrupts and bottom half handlers won't change it 871 * from under us. It essentially blocks any incoming 872 * packets, so that we won't get any new data or any 873 * packets that change the state of the socket. 874 * 875 * While locked, BH processing will add new packets to 876 * the backlog queue. This queue is processed by the 877 * owner of the socket lock right before it is released. 878 * 879 * Since ~2.3.5 it is also exclusive sleep lock serializing 880 * accesses from user process context. 881 */ 882 #define sock_owned_by_user(sk) ((sk)->sk_lock.owned) 883 884 /* 885 * Macro so as to not evaluate some arguments when 886 * lockdep is not enabled. 887 * 888 * Mark both the sk_lock and the sk_lock.slock as a 889 * per-address-family lock class. 890 */ 891 #define sock_lock_init_class_and_name(sk, sname, skey, name, key) \ 892 do { \ 893 sk->sk_lock.owned = 0; \ 894 init_waitqueue_head(&sk->sk_lock.wq); \ 895 spin_lock_init(&(sk)->sk_lock.slock); \ 896 debug_check_no_locks_freed((void *)&(sk)->sk_lock, \ 897 sizeof((sk)->sk_lock)); \ 898 lockdep_set_class_and_name(&(sk)->sk_lock.slock, \ 899 (skey), (sname)); \ 900 lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \ 901 } while (0) 902 903 extern void lock_sock_nested(struct sock *sk, int subclass); 904 905 static inline void lock_sock(struct sock *sk) 906 { 907 lock_sock_nested(sk, 0); 908 } 909 910 extern void release_sock(struct sock *sk); 911 912 /* BH context may only use the following locking interface. */ 913 #define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock)) 914 #define bh_lock_sock_nested(__sk) \ 915 spin_lock_nested(&((__sk)->sk_lock.slock), \ 916 SINGLE_DEPTH_NESTING) 917 #define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock)) 918 919 extern struct sock *sk_alloc(struct net *net, int family, 920 gfp_t priority, 921 struct proto *prot); 922 extern void sk_free(struct sock *sk); 923 extern void sk_release_kernel(struct sock *sk); 924 extern struct sock *sk_clone(const struct sock *sk, 925 const gfp_t priority); 926 927 extern struct sk_buff *sock_wmalloc(struct sock *sk, 928 unsigned long size, int force, 929 gfp_t priority); 930 extern struct sk_buff *sock_rmalloc(struct sock *sk, 931 unsigned long size, int force, 932 gfp_t priority); 933 extern void sock_wfree(struct sk_buff *skb); 934 extern void sock_rfree(struct sk_buff *skb); 935 936 extern int sock_setsockopt(struct socket *sock, int level, 937 int op, char __user *optval, 938 int optlen); 939 940 extern int sock_getsockopt(struct socket *sock, int level, 941 int op, char __user *optval, 942 int __user *optlen); 943 extern struct sk_buff *sock_alloc_send_skb(struct sock *sk, 944 unsigned long size, 945 int noblock, 946 int *errcode); 947 extern void *sock_kmalloc(struct sock *sk, int size, 948 gfp_t priority); 949 extern void sock_kfree_s(struct sock *sk, void *mem, int size); 950 extern void sk_send_sigurg(struct sock *sk); 951 952 /* 953 * Functions to fill in entries in struct proto_ops when a protocol 954 * does not implement a particular function. 955 */ 956 extern int sock_no_bind(struct socket *, 957 struct sockaddr *, int); 958 extern int sock_no_connect(struct socket *, 959 struct sockaddr *, int, int); 960 extern int sock_no_socketpair(struct socket *, 961 struct socket *); 962 extern int sock_no_accept(struct socket *, 963 struct socket *, int); 964 extern int sock_no_getname(struct socket *, 965 struct sockaddr *, int *, int); 966 extern unsigned int sock_no_poll(struct file *, struct socket *, 967 struct poll_table_struct *); 968 extern int sock_no_ioctl(struct socket *, unsigned int, 969 unsigned long); 970 extern int sock_no_listen(struct socket *, int); 971 extern int sock_no_shutdown(struct socket *, int); 972 extern int sock_no_getsockopt(struct socket *, int , int, 973 char __user *, int __user *); 974 extern int sock_no_setsockopt(struct socket *, int, int, 975 char __user *, int); 976 extern int sock_no_sendmsg(struct kiocb *, struct socket *, 977 struct msghdr *, size_t); 978 extern int sock_no_recvmsg(struct kiocb *, struct socket *, 979 struct msghdr *, size_t, int); 980 extern int sock_no_mmap(struct file *file, 981 struct socket *sock, 982 struct vm_area_struct *vma); 983 extern ssize_t sock_no_sendpage(struct socket *sock, 984 struct page *page, 985 int offset, size_t size, 986 int flags); 987 988 /* 989 * Functions to fill in entries in struct proto_ops when a protocol 990 * uses the inet style. 991 */ 992 extern int sock_common_getsockopt(struct socket *sock, int level, int optname, 993 char __user *optval, int __user *optlen); 994 extern int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock, 995 struct msghdr *msg, size_t size, int flags); 996 extern int sock_common_setsockopt(struct socket *sock, int level, int optname, 997 char __user *optval, int optlen); 998 extern int compat_sock_common_getsockopt(struct socket *sock, int level, 999 int optname, char __user *optval, int __user *optlen); 1000 extern int compat_sock_common_setsockopt(struct socket *sock, int level, 1001 int optname, char __user *optval, int optlen); 1002 1003 extern void sk_common_release(struct sock *sk); 1004 1005 /* 1006 * Default socket callbacks and setup code 1007 */ 1008 1009 /* Initialise core socket variables */ 1010 extern void sock_init_data(struct socket *sock, struct sock *sk); 1011 1012 /** 1013 * sk_filter_release: Release a socket filter 1014 * @fp: filter to remove 1015 * 1016 * Remove a filter from a socket and release its resources. 1017 */ 1018 1019 static inline void sk_filter_release(struct sk_filter *fp) 1020 { 1021 if (atomic_dec_and_test(&fp->refcnt)) 1022 kfree(fp); 1023 } 1024 1025 static inline void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp) 1026 { 1027 unsigned int size = sk_filter_len(fp); 1028 1029 atomic_sub(size, &sk->sk_omem_alloc); 1030 sk_filter_release(fp); 1031 } 1032 1033 static inline void sk_filter_charge(struct sock *sk, struct sk_filter *fp) 1034 { 1035 atomic_inc(&fp->refcnt); 1036 atomic_add(sk_filter_len(fp), &sk->sk_omem_alloc); 1037 } 1038 1039 /* 1040 * Socket reference counting postulates. 1041 * 1042 * * Each user of socket SHOULD hold a reference count. 1043 * * Each access point to socket (an hash table bucket, reference from a list, 1044 * running timer, skb in flight MUST hold a reference count. 1045 * * When reference count hits 0, it means it will never increase back. 1046 * * When reference count hits 0, it means that no references from 1047 * outside exist to this socket and current process on current CPU 1048 * is last user and may/should destroy this socket. 1049 * * sk_free is called from any context: process, BH, IRQ. When 1050 * it is called, socket has no references from outside -> sk_free 1051 * may release descendant resources allocated by the socket, but 1052 * to the time when it is called, socket is NOT referenced by any 1053 * hash tables, lists etc. 1054 * * Packets, delivered from outside (from network or from another process) 1055 * and enqueued on receive/error queues SHOULD NOT grab reference count, 1056 * when they sit in queue. Otherwise, packets will leak to hole, when 1057 * socket is looked up by one cpu and unhasing is made by another CPU. 1058 * It is true for udp/raw, netlink (leak to receive and error queues), tcp 1059 * (leak to backlog). Packet socket does all the processing inside 1060 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets 1061 * use separate SMP lock, so that they are prone too. 1062 */ 1063 1064 /* Ungrab socket and destroy it, if it was the last reference. */ 1065 static inline void sock_put(struct sock *sk) 1066 { 1067 if (atomic_dec_and_test(&sk->sk_refcnt)) 1068 sk_free(sk); 1069 } 1070 1071 extern int sk_receive_skb(struct sock *sk, struct sk_buff *skb, 1072 const int nested); 1073 1074 static inline void sk_set_socket(struct sock *sk, struct socket *sock) 1075 { 1076 sk->sk_socket = sock; 1077 } 1078 1079 /* Detach socket from process context. 1080 * Announce socket dead, detach it from wait queue and inode. 1081 * Note that parent inode held reference count on this struct sock, 1082 * we do not release it in this function, because protocol 1083 * probably wants some additional cleanups or even continuing 1084 * to work with this socket (TCP). 1085 */ 1086 static inline void sock_orphan(struct sock *sk) 1087 { 1088 write_lock_bh(&sk->sk_callback_lock); 1089 sock_set_flag(sk, SOCK_DEAD); 1090 sk_set_socket(sk, NULL); 1091 sk->sk_sleep = NULL; 1092 write_unlock_bh(&sk->sk_callback_lock); 1093 } 1094 1095 static inline void sock_graft(struct sock *sk, struct socket *parent) 1096 { 1097 write_lock_bh(&sk->sk_callback_lock); 1098 sk->sk_sleep = &parent->wait; 1099 parent->sk = sk; 1100 sk_set_socket(sk, parent); 1101 security_sock_graft(sk, parent); 1102 write_unlock_bh(&sk->sk_callback_lock); 1103 } 1104 1105 extern int sock_i_uid(struct sock *sk); 1106 extern unsigned long sock_i_ino(struct sock *sk); 1107 1108 static inline struct dst_entry * 1109 __sk_dst_get(struct sock *sk) 1110 { 1111 return sk->sk_dst_cache; 1112 } 1113 1114 static inline struct dst_entry * 1115 sk_dst_get(struct sock *sk) 1116 { 1117 struct dst_entry *dst; 1118 1119 read_lock(&sk->sk_dst_lock); 1120 dst = sk->sk_dst_cache; 1121 if (dst) 1122 dst_hold(dst); 1123 read_unlock(&sk->sk_dst_lock); 1124 return dst; 1125 } 1126 1127 static inline void 1128 __sk_dst_set(struct sock *sk, struct dst_entry *dst) 1129 { 1130 struct dst_entry *old_dst; 1131 1132 old_dst = sk->sk_dst_cache; 1133 sk->sk_dst_cache = dst; 1134 dst_release(old_dst); 1135 } 1136 1137 static inline void 1138 sk_dst_set(struct sock *sk, struct dst_entry *dst) 1139 { 1140 write_lock(&sk->sk_dst_lock); 1141 __sk_dst_set(sk, dst); 1142 write_unlock(&sk->sk_dst_lock); 1143 } 1144 1145 static inline void 1146 __sk_dst_reset(struct sock *sk) 1147 { 1148 struct dst_entry *old_dst; 1149 1150 old_dst = sk->sk_dst_cache; 1151 sk->sk_dst_cache = NULL; 1152 dst_release(old_dst); 1153 } 1154 1155 static inline void 1156 sk_dst_reset(struct sock *sk) 1157 { 1158 write_lock(&sk->sk_dst_lock); 1159 __sk_dst_reset(sk); 1160 write_unlock(&sk->sk_dst_lock); 1161 } 1162 1163 extern struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie); 1164 1165 extern struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie); 1166 1167 static inline int sk_can_gso(const struct sock *sk) 1168 { 1169 return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type); 1170 } 1171 1172 extern void sk_setup_caps(struct sock *sk, struct dst_entry *dst); 1173 1174 static inline int skb_copy_to_page(struct sock *sk, char __user *from, 1175 struct sk_buff *skb, struct page *page, 1176 int off, int copy) 1177 { 1178 if (skb->ip_summed == CHECKSUM_NONE) { 1179 int err = 0; 1180 __wsum csum = csum_and_copy_from_user(from, 1181 page_address(page) + off, 1182 copy, 0, &err); 1183 if (err) 1184 return err; 1185 skb->csum = csum_block_add(skb->csum, csum, skb->len); 1186 } else if (copy_from_user(page_address(page) + off, from, copy)) 1187 return -EFAULT; 1188 1189 skb->len += copy; 1190 skb->data_len += copy; 1191 skb->truesize += copy; 1192 sk->sk_wmem_queued += copy; 1193 sk_mem_charge(sk, copy); 1194 return 0; 1195 } 1196 1197 /* 1198 * Queue a received datagram if it will fit. Stream and sequenced 1199 * protocols can't normally use this as they need to fit buffers in 1200 * and play with them. 1201 * 1202 * Inlined as it's very short and called for pretty much every 1203 * packet ever received. 1204 */ 1205 1206 static inline void skb_set_owner_w(struct sk_buff *skb, struct sock *sk) 1207 { 1208 sock_hold(sk); 1209 skb->sk = sk; 1210 skb->destructor = sock_wfree; 1211 atomic_add(skb->truesize, &sk->sk_wmem_alloc); 1212 } 1213 1214 static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk) 1215 { 1216 skb->sk = sk; 1217 skb->destructor = sock_rfree; 1218 atomic_add(skb->truesize, &sk->sk_rmem_alloc); 1219 sk_mem_charge(sk, skb->truesize); 1220 } 1221 1222 extern void sk_reset_timer(struct sock *sk, struct timer_list* timer, 1223 unsigned long expires); 1224 1225 extern void sk_stop_timer(struct sock *sk, struct timer_list* timer); 1226 1227 extern int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb); 1228 1229 static inline int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb) 1230 { 1231 /* Cast skb->rcvbuf to unsigned... It's pointless, but reduces 1232 number of warnings when compiling with -W --ANK 1233 */ 1234 if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >= 1235 (unsigned)sk->sk_rcvbuf) 1236 return -ENOMEM; 1237 skb_set_owner_r(skb, sk); 1238 skb_queue_tail(&sk->sk_error_queue, skb); 1239 if (!sock_flag(sk, SOCK_DEAD)) 1240 sk->sk_data_ready(sk, skb->len); 1241 return 0; 1242 } 1243 1244 /* 1245 * Recover an error report and clear atomically 1246 */ 1247 1248 static inline int sock_error(struct sock *sk) 1249 { 1250 int err; 1251 if (likely(!sk->sk_err)) 1252 return 0; 1253 err = xchg(&sk->sk_err, 0); 1254 return -err; 1255 } 1256 1257 static inline unsigned long sock_wspace(struct sock *sk) 1258 { 1259 int amt = 0; 1260 1261 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) { 1262 amt = sk->sk_sndbuf - atomic_read(&sk->sk_wmem_alloc); 1263 if (amt < 0) 1264 amt = 0; 1265 } 1266 return amt; 1267 } 1268 1269 static inline void sk_wake_async(struct sock *sk, int how, int band) 1270 { 1271 if (sk->sk_socket && sk->sk_socket->fasync_list) 1272 sock_wake_async(sk->sk_socket, how, band); 1273 } 1274 1275 #define SOCK_MIN_SNDBUF 2048 1276 #define SOCK_MIN_RCVBUF 256 1277 1278 static inline void sk_stream_moderate_sndbuf(struct sock *sk) 1279 { 1280 if (!(sk->sk_userlocks & SOCK_SNDBUF_LOCK)) { 1281 sk->sk_sndbuf = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1); 1282 sk->sk_sndbuf = max(sk->sk_sndbuf, SOCK_MIN_SNDBUF); 1283 } 1284 } 1285 1286 struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp); 1287 1288 static inline struct page *sk_stream_alloc_page(struct sock *sk) 1289 { 1290 struct page *page = NULL; 1291 1292 page = alloc_pages(sk->sk_allocation, 0); 1293 if (!page) { 1294 sk->sk_prot->enter_memory_pressure(sk); 1295 sk_stream_moderate_sndbuf(sk); 1296 } 1297 return page; 1298 } 1299 1300 /* 1301 * Default write policy as shown to user space via poll/select/SIGIO 1302 */ 1303 static inline int sock_writeable(const struct sock *sk) 1304 { 1305 return atomic_read(&sk->sk_wmem_alloc) < (sk->sk_sndbuf >> 1); 1306 } 1307 1308 static inline gfp_t gfp_any(void) 1309 { 1310 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL; 1311 } 1312 1313 static inline long sock_rcvtimeo(const struct sock *sk, int noblock) 1314 { 1315 return noblock ? 0 : sk->sk_rcvtimeo; 1316 } 1317 1318 static inline long sock_sndtimeo(const struct sock *sk, int noblock) 1319 { 1320 return noblock ? 0 : sk->sk_sndtimeo; 1321 } 1322 1323 static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len) 1324 { 1325 return (waitall ? len : min_t(int, sk->sk_rcvlowat, len)) ? : 1; 1326 } 1327 1328 /* Alas, with timeout socket operations are not restartable. 1329 * Compare this to poll(). 1330 */ 1331 static inline int sock_intr_errno(long timeo) 1332 { 1333 return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR; 1334 } 1335 1336 extern void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk, 1337 struct sk_buff *skb); 1338 1339 static __inline__ void 1340 sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb) 1341 { 1342 ktime_t kt = skb->tstamp; 1343 1344 if (sock_flag(sk, SOCK_RCVTSTAMP)) 1345 __sock_recv_timestamp(msg, sk, skb); 1346 else 1347 sk->sk_stamp = kt; 1348 } 1349 1350 /** 1351 * sk_eat_skb - Release a skb if it is no longer needed 1352 * @sk: socket to eat this skb from 1353 * @skb: socket buffer to eat 1354 * @copied_early: flag indicating whether DMA operations copied this data early 1355 * 1356 * This routine must be called with interrupts disabled or with the socket 1357 * locked so that the sk_buff queue operation is ok. 1358 */ 1359 #ifdef CONFIG_NET_DMA 1360 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb, int copied_early) 1361 { 1362 __skb_unlink(skb, &sk->sk_receive_queue); 1363 if (!copied_early) 1364 __kfree_skb(skb); 1365 else 1366 __skb_queue_tail(&sk->sk_async_wait_queue, skb); 1367 } 1368 #else 1369 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb, int copied_early) 1370 { 1371 __skb_unlink(skb, &sk->sk_receive_queue); 1372 __kfree_skb(skb); 1373 } 1374 #endif 1375 1376 static inline 1377 struct net *sock_net(const struct sock *sk) 1378 { 1379 #ifdef CONFIG_NET_NS 1380 return sk->sk_net; 1381 #else 1382 return &init_net; 1383 #endif 1384 } 1385 1386 static inline 1387 void sock_net_set(struct sock *sk, struct net *net) 1388 { 1389 #ifdef CONFIG_NET_NS 1390 sk->sk_net = net; 1391 #endif 1392 } 1393 1394 /* 1395 * Kernel sockets, f.e. rtnl or icmp_socket, are a part of a namespace. 1396 * They should not hold a referrence to a namespace in order to allow 1397 * to stop it. 1398 * Sockets after sk_change_net should be released using sk_release_kernel 1399 */ 1400 static inline void sk_change_net(struct sock *sk, struct net *net) 1401 { 1402 put_net(sock_net(sk)); 1403 sock_net_set(sk, hold_net(net)); 1404 } 1405 1406 static inline struct sock *skb_steal_sock(struct sk_buff *skb) 1407 { 1408 if (unlikely(skb->sk)) { 1409 struct sock *sk = skb->sk; 1410 1411 skb->destructor = NULL; 1412 skb->sk = NULL; 1413 return sk; 1414 } 1415 return NULL; 1416 } 1417 1418 extern void sock_enable_timestamp(struct sock *sk); 1419 extern int sock_get_timestamp(struct sock *, struct timeval __user *); 1420 extern int sock_get_timestampns(struct sock *, struct timespec __user *); 1421 1422 /* 1423 * Enable debug/info messages 1424 */ 1425 extern int net_msg_warn; 1426 #define NETDEBUG(fmt, args...) \ 1427 do { if (net_msg_warn) printk(fmt,##args); } while (0) 1428 1429 #define LIMIT_NETDEBUG(fmt, args...) \ 1430 do { if (net_msg_warn && net_ratelimit()) printk(fmt,##args); } while(0) 1431 1432 extern __u32 sysctl_wmem_max; 1433 extern __u32 sysctl_rmem_max; 1434 1435 extern void sk_init(void); 1436 1437 extern int sysctl_optmem_max; 1438 1439 extern __u32 sysctl_wmem_default; 1440 extern __u32 sysctl_rmem_default; 1441 1442 #endif /* _SOCK_H */ 1443