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