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/bitops.h> 50 #include <linux/lockdep.h> 51 #include <linux/netdevice.h> 52 #include <linux/skbuff.h> /* struct sk_buff */ 53 #include <linux/mm.h> 54 #include <linux/security.h> 55 #include <linux/slab.h> 56 #include <linux/uaccess.h> 57 #include <linux/memcontrol.h> 58 #include <linux/res_counter.h> 59 #include <linux/static_key.h> 60 #include <linux/aio.h> 61 #include <linux/sched.h> 62 63 #include <linux/filter.h> 64 #include <linux/rculist_nulls.h> 65 #include <linux/poll.h> 66 67 #include <linux/atomic.h> 68 #include <net/dst.h> 69 #include <net/checksum.h> 70 71 struct cgroup; 72 struct cgroup_subsys; 73 #ifdef CONFIG_NET 74 int mem_cgroup_sockets_init(struct mem_cgroup *memcg, struct cgroup_subsys *ss); 75 void mem_cgroup_sockets_destroy(struct mem_cgroup *memcg); 76 #else 77 static inline 78 int mem_cgroup_sockets_init(struct mem_cgroup *memcg, struct cgroup_subsys *ss) 79 { 80 return 0; 81 } 82 static inline 83 void mem_cgroup_sockets_destroy(struct mem_cgroup *memcg) 84 { 85 } 86 #endif 87 /* 88 * This structure really needs to be cleaned up. 89 * Most of it is for TCP, and not used by any of 90 * the other protocols. 91 */ 92 93 /* Define this to get the SOCK_DBG debugging facility. */ 94 #define SOCK_DEBUGGING 95 #ifdef SOCK_DEBUGGING 96 #define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \ 97 printk(KERN_DEBUG msg); } while (0) 98 #else 99 /* Validate arguments and do nothing */ 100 static inline __printf(2, 3) 101 void SOCK_DEBUG(const struct sock *sk, const char *msg, ...) 102 { 103 } 104 #endif 105 106 /* This is the per-socket lock. The spinlock provides a synchronization 107 * between user contexts and software interrupt processing, whereas the 108 * mini-semaphore synchronizes multiple users amongst themselves. 109 */ 110 typedef struct { 111 spinlock_t slock; 112 int owned; 113 wait_queue_head_t wq; 114 /* 115 * We express the mutex-alike socket_lock semantics 116 * to the lock validator by explicitly managing 117 * the slock as a lock variant (in addition to 118 * the slock itself): 119 */ 120 #ifdef CONFIG_DEBUG_LOCK_ALLOC 121 struct lockdep_map dep_map; 122 #endif 123 } socket_lock_t; 124 125 struct sock; 126 struct proto; 127 struct net; 128 129 /** 130 * struct sock_common - minimal network layer representation of sockets 131 * @skc_daddr: Foreign IPv4 addr 132 * @skc_rcv_saddr: Bound local IPv4 addr 133 * @skc_hash: hash value used with various protocol lookup tables 134 * @skc_u16hashes: two u16 hash values used by UDP lookup tables 135 * @skc_family: network address family 136 * @skc_state: Connection state 137 * @skc_reuse: %SO_REUSEADDR setting 138 * @skc_bound_dev_if: bound device index if != 0 139 * @skc_bind_node: bind hash linkage for various protocol lookup tables 140 * @skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol 141 * @skc_prot: protocol handlers inside a network family 142 * @skc_net: reference to the network namespace of this socket 143 * @skc_node: main hash linkage for various protocol lookup tables 144 * @skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol 145 * @skc_tx_queue_mapping: tx queue number for this connection 146 * @skc_refcnt: reference count 147 * 148 * This is the minimal network layer representation of sockets, the header 149 * for struct sock and struct inet_timewait_sock. 150 */ 151 struct sock_common { 152 /* skc_daddr and skc_rcv_saddr must be grouped : 153 * cf INET_MATCH() and INET_TW_MATCH() 154 */ 155 __be32 skc_daddr; 156 __be32 skc_rcv_saddr; 157 158 union { 159 unsigned int skc_hash; 160 __u16 skc_u16hashes[2]; 161 }; 162 unsigned short skc_family; 163 volatile unsigned char skc_state; 164 unsigned char skc_reuse; 165 int skc_bound_dev_if; 166 union { 167 struct hlist_node skc_bind_node; 168 struct hlist_nulls_node skc_portaddr_node; 169 }; 170 struct proto *skc_prot; 171 #ifdef CONFIG_NET_NS 172 struct net *skc_net; 173 #endif 174 /* 175 * fields between dontcopy_begin/dontcopy_end 176 * are not copied in sock_copy() 177 */ 178 /* private: */ 179 int skc_dontcopy_begin[0]; 180 /* public: */ 181 union { 182 struct hlist_node skc_node; 183 struct hlist_nulls_node skc_nulls_node; 184 }; 185 int skc_tx_queue_mapping; 186 atomic_t skc_refcnt; 187 /* private: */ 188 int skc_dontcopy_end[0]; 189 /* public: */ 190 }; 191 192 struct cg_proto; 193 /** 194 * struct sock - network layer representation of sockets 195 * @__sk_common: shared layout with inet_timewait_sock 196 * @sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN 197 * @sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings 198 * @sk_lock: synchronizer 199 * @sk_rcvbuf: size of receive buffer in bytes 200 * @sk_wq: sock wait queue and async head 201 * @sk_rx_dst: receive input route used by early tcp demux 202 * @sk_dst_cache: destination cache 203 * @sk_dst_lock: destination cache lock 204 * @sk_policy: flow policy 205 * @sk_receive_queue: incoming packets 206 * @sk_wmem_alloc: transmit queue bytes committed 207 * @sk_write_queue: Packet sending queue 208 * @sk_async_wait_queue: DMA copied packets 209 * @sk_omem_alloc: "o" is "option" or "other" 210 * @sk_wmem_queued: persistent queue size 211 * @sk_forward_alloc: space allocated forward 212 * @sk_allocation: allocation mode 213 * @sk_sndbuf: size of send buffer in bytes 214 * @sk_flags: %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE, 215 * %SO_OOBINLINE settings, %SO_TIMESTAMPING settings 216 * @sk_no_check: %SO_NO_CHECK setting, wether or not checkup packets 217 * @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO) 218 * @sk_route_nocaps: forbidden route capabilities (e.g NETIF_F_GSO_MASK) 219 * @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4) 220 * @sk_gso_max_size: Maximum GSO segment size to build 221 * @sk_gso_max_segs: Maximum number of GSO segments 222 * @sk_lingertime: %SO_LINGER l_linger setting 223 * @sk_backlog: always used with the per-socket spinlock held 224 * @sk_callback_lock: used with the callbacks in the end of this struct 225 * @sk_error_queue: rarely used 226 * @sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt, 227 * IPV6_ADDRFORM for instance) 228 * @sk_err: last error 229 * @sk_err_soft: errors that don't cause failure but are the cause of a 230 * persistent failure not just 'timed out' 231 * @sk_drops: raw/udp drops counter 232 * @sk_ack_backlog: current listen backlog 233 * @sk_max_ack_backlog: listen backlog set in listen() 234 * @sk_priority: %SO_PRIORITY setting 235 * @sk_cgrp_prioidx: socket group's priority map index 236 * @sk_type: socket type (%SOCK_STREAM, etc) 237 * @sk_protocol: which protocol this socket belongs in this network family 238 * @sk_peer_pid: &struct pid for this socket's peer 239 * @sk_peer_cred: %SO_PEERCRED setting 240 * @sk_rcvlowat: %SO_RCVLOWAT setting 241 * @sk_rcvtimeo: %SO_RCVTIMEO setting 242 * @sk_sndtimeo: %SO_SNDTIMEO setting 243 * @sk_rxhash: flow hash received from netif layer 244 * @sk_filter: socket filtering instructions 245 * @sk_protinfo: private area, net family specific, when not using slab 246 * @sk_timer: sock cleanup timer 247 * @sk_stamp: time stamp of last packet received 248 * @sk_socket: Identd and reporting IO signals 249 * @sk_user_data: RPC layer private data 250 * @sk_sndmsg_page: cached page for sendmsg 251 * @sk_sndmsg_off: cached offset for sendmsg 252 * @sk_peek_off: current peek_offset value 253 * @sk_send_head: front of stuff to transmit 254 * @sk_security: used by security modules 255 * @sk_mark: generic packet mark 256 * @sk_classid: this socket's cgroup classid 257 * @sk_cgrp: this socket's cgroup-specific proto data 258 * @sk_write_pending: a write to stream socket waits to start 259 * @sk_state_change: callback to indicate change in the state of the sock 260 * @sk_data_ready: callback to indicate there is data to be processed 261 * @sk_write_space: callback to indicate there is bf sending space available 262 * @sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE) 263 * @sk_backlog_rcv: callback to process the backlog 264 * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0 265 */ 266 struct sock { 267 /* 268 * Now struct inet_timewait_sock also uses sock_common, so please just 269 * don't add nothing before this first member (__sk_common) --acme 270 */ 271 struct sock_common __sk_common; 272 #define sk_node __sk_common.skc_node 273 #define sk_nulls_node __sk_common.skc_nulls_node 274 #define sk_refcnt __sk_common.skc_refcnt 275 #define sk_tx_queue_mapping __sk_common.skc_tx_queue_mapping 276 277 #define sk_dontcopy_begin __sk_common.skc_dontcopy_begin 278 #define sk_dontcopy_end __sk_common.skc_dontcopy_end 279 #define sk_hash __sk_common.skc_hash 280 #define sk_family __sk_common.skc_family 281 #define sk_state __sk_common.skc_state 282 #define sk_reuse __sk_common.skc_reuse 283 #define sk_bound_dev_if __sk_common.skc_bound_dev_if 284 #define sk_bind_node __sk_common.skc_bind_node 285 #define sk_prot __sk_common.skc_prot 286 #define sk_net __sk_common.skc_net 287 socket_lock_t sk_lock; 288 struct sk_buff_head sk_receive_queue; 289 /* 290 * The backlog queue is special, it is always used with 291 * the per-socket spinlock held and requires low latency 292 * access. Therefore we special case it's implementation. 293 * Note : rmem_alloc is in this structure to fill a hole 294 * on 64bit arches, not because its logically part of 295 * backlog. 296 */ 297 struct { 298 atomic_t rmem_alloc; 299 int len; 300 struct sk_buff *head; 301 struct sk_buff *tail; 302 } sk_backlog; 303 #define sk_rmem_alloc sk_backlog.rmem_alloc 304 int sk_forward_alloc; 305 #ifdef CONFIG_RPS 306 __u32 sk_rxhash; 307 #endif 308 atomic_t sk_drops; 309 int sk_rcvbuf; 310 311 struct sk_filter __rcu *sk_filter; 312 struct socket_wq __rcu *sk_wq; 313 314 #ifdef CONFIG_NET_DMA 315 struct sk_buff_head sk_async_wait_queue; 316 #endif 317 318 #ifdef CONFIG_XFRM 319 struct xfrm_policy *sk_policy[2]; 320 #endif 321 unsigned long sk_flags; 322 struct dst_entry *sk_rx_dst; 323 struct dst_entry *sk_dst_cache; 324 spinlock_t sk_dst_lock; 325 atomic_t sk_wmem_alloc; 326 atomic_t sk_omem_alloc; 327 int sk_sndbuf; 328 struct sk_buff_head sk_write_queue; 329 kmemcheck_bitfield_begin(flags); 330 unsigned int sk_shutdown : 2, 331 sk_no_check : 2, 332 sk_userlocks : 4, 333 sk_protocol : 8, 334 sk_type : 16; 335 kmemcheck_bitfield_end(flags); 336 int sk_wmem_queued; 337 gfp_t sk_allocation; 338 netdev_features_t sk_route_caps; 339 netdev_features_t sk_route_nocaps; 340 int sk_gso_type; 341 unsigned int sk_gso_max_size; 342 u16 sk_gso_max_segs; 343 int sk_rcvlowat; 344 unsigned long sk_lingertime; 345 struct sk_buff_head sk_error_queue; 346 struct proto *sk_prot_creator; 347 rwlock_t sk_callback_lock; 348 int sk_err, 349 sk_err_soft; 350 unsigned short sk_ack_backlog; 351 unsigned short sk_max_ack_backlog; 352 __u32 sk_priority; 353 #ifdef CONFIG_CGROUPS 354 __u32 sk_cgrp_prioidx; 355 #endif 356 struct pid *sk_peer_pid; 357 const struct cred *sk_peer_cred; 358 long sk_rcvtimeo; 359 long sk_sndtimeo; 360 void *sk_protinfo; 361 struct timer_list sk_timer; 362 ktime_t sk_stamp; 363 struct socket *sk_socket; 364 void *sk_user_data; 365 struct page *sk_sndmsg_page; 366 struct sk_buff *sk_send_head; 367 __u32 sk_sndmsg_off; 368 __s32 sk_peek_off; 369 int sk_write_pending; 370 #ifdef CONFIG_SECURITY 371 void *sk_security; 372 #endif 373 __u32 sk_mark; 374 u32 sk_classid; 375 struct cg_proto *sk_cgrp; 376 void (*sk_state_change)(struct sock *sk); 377 void (*sk_data_ready)(struct sock *sk, int bytes); 378 void (*sk_write_space)(struct sock *sk); 379 void (*sk_error_report)(struct sock *sk); 380 int (*sk_backlog_rcv)(struct sock *sk, 381 struct sk_buff *skb); 382 void (*sk_destruct)(struct sock *sk); 383 }; 384 385 /* 386 * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK 387 * or not whether his port will be reused by someone else. SK_FORCE_REUSE 388 * on a socket means that the socket will reuse everybody else's port 389 * without looking at the other's sk_reuse value. 390 */ 391 392 #define SK_NO_REUSE 0 393 #define SK_CAN_REUSE 1 394 #define SK_FORCE_REUSE 2 395 396 static inline int sk_peek_offset(struct sock *sk, int flags) 397 { 398 if ((flags & MSG_PEEK) && (sk->sk_peek_off >= 0)) 399 return sk->sk_peek_off; 400 else 401 return 0; 402 } 403 404 static inline void sk_peek_offset_bwd(struct sock *sk, int val) 405 { 406 if (sk->sk_peek_off >= 0) { 407 if (sk->sk_peek_off >= val) 408 sk->sk_peek_off -= val; 409 else 410 sk->sk_peek_off = 0; 411 } 412 } 413 414 static inline void sk_peek_offset_fwd(struct sock *sk, int val) 415 { 416 if (sk->sk_peek_off >= 0) 417 sk->sk_peek_off += val; 418 } 419 420 /* 421 * Hashed lists helper routines 422 */ 423 static inline struct sock *sk_entry(const struct hlist_node *node) 424 { 425 return hlist_entry(node, struct sock, sk_node); 426 } 427 428 static inline struct sock *__sk_head(const struct hlist_head *head) 429 { 430 return hlist_entry(head->first, struct sock, sk_node); 431 } 432 433 static inline struct sock *sk_head(const struct hlist_head *head) 434 { 435 return hlist_empty(head) ? NULL : __sk_head(head); 436 } 437 438 static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head) 439 { 440 return hlist_nulls_entry(head->first, struct sock, sk_nulls_node); 441 } 442 443 static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head) 444 { 445 return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head); 446 } 447 448 static inline struct sock *sk_next(const struct sock *sk) 449 { 450 return sk->sk_node.next ? 451 hlist_entry(sk->sk_node.next, struct sock, sk_node) : NULL; 452 } 453 454 static inline struct sock *sk_nulls_next(const struct sock *sk) 455 { 456 return (!is_a_nulls(sk->sk_nulls_node.next)) ? 457 hlist_nulls_entry(sk->sk_nulls_node.next, 458 struct sock, sk_nulls_node) : 459 NULL; 460 } 461 462 static inline bool sk_unhashed(const struct sock *sk) 463 { 464 return hlist_unhashed(&sk->sk_node); 465 } 466 467 static inline bool sk_hashed(const struct sock *sk) 468 { 469 return !sk_unhashed(sk); 470 } 471 472 static inline void sk_node_init(struct hlist_node *node) 473 { 474 node->pprev = NULL; 475 } 476 477 static inline void sk_nulls_node_init(struct hlist_nulls_node *node) 478 { 479 node->pprev = NULL; 480 } 481 482 static inline void __sk_del_node(struct sock *sk) 483 { 484 __hlist_del(&sk->sk_node); 485 } 486 487 /* NB: equivalent to hlist_del_init_rcu */ 488 static inline bool __sk_del_node_init(struct sock *sk) 489 { 490 if (sk_hashed(sk)) { 491 __sk_del_node(sk); 492 sk_node_init(&sk->sk_node); 493 return true; 494 } 495 return false; 496 } 497 498 /* Grab socket reference count. This operation is valid only 499 when sk is ALREADY grabbed f.e. it is found in hash table 500 or a list and the lookup is made under lock preventing hash table 501 modifications. 502 */ 503 504 static inline void sock_hold(struct sock *sk) 505 { 506 atomic_inc(&sk->sk_refcnt); 507 } 508 509 /* Ungrab socket in the context, which assumes that socket refcnt 510 cannot hit zero, f.e. it is true in context of any socketcall. 511 */ 512 static inline void __sock_put(struct sock *sk) 513 { 514 atomic_dec(&sk->sk_refcnt); 515 } 516 517 static inline bool sk_del_node_init(struct sock *sk) 518 { 519 bool rc = __sk_del_node_init(sk); 520 521 if (rc) { 522 /* paranoid for a while -acme */ 523 WARN_ON(atomic_read(&sk->sk_refcnt) == 1); 524 __sock_put(sk); 525 } 526 return rc; 527 } 528 #define sk_del_node_init_rcu(sk) sk_del_node_init(sk) 529 530 static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk) 531 { 532 if (sk_hashed(sk)) { 533 hlist_nulls_del_init_rcu(&sk->sk_nulls_node); 534 return true; 535 } 536 return false; 537 } 538 539 static inline bool sk_nulls_del_node_init_rcu(struct sock *sk) 540 { 541 bool rc = __sk_nulls_del_node_init_rcu(sk); 542 543 if (rc) { 544 /* paranoid for a while -acme */ 545 WARN_ON(atomic_read(&sk->sk_refcnt) == 1); 546 __sock_put(sk); 547 } 548 return rc; 549 } 550 551 static inline void __sk_add_node(struct sock *sk, struct hlist_head *list) 552 { 553 hlist_add_head(&sk->sk_node, list); 554 } 555 556 static inline void sk_add_node(struct sock *sk, struct hlist_head *list) 557 { 558 sock_hold(sk); 559 __sk_add_node(sk, list); 560 } 561 562 static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list) 563 { 564 sock_hold(sk); 565 hlist_add_head_rcu(&sk->sk_node, list); 566 } 567 568 static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list) 569 { 570 hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list); 571 } 572 573 static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list) 574 { 575 sock_hold(sk); 576 __sk_nulls_add_node_rcu(sk, list); 577 } 578 579 static inline void __sk_del_bind_node(struct sock *sk) 580 { 581 __hlist_del(&sk->sk_bind_node); 582 } 583 584 static inline void sk_add_bind_node(struct sock *sk, 585 struct hlist_head *list) 586 { 587 hlist_add_head(&sk->sk_bind_node, list); 588 } 589 590 #define sk_for_each(__sk, node, list) \ 591 hlist_for_each_entry(__sk, node, list, sk_node) 592 #define sk_for_each_rcu(__sk, node, list) \ 593 hlist_for_each_entry_rcu(__sk, node, list, sk_node) 594 #define sk_nulls_for_each(__sk, node, list) \ 595 hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node) 596 #define sk_nulls_for_each_rcu(__sk, node, list) \ 597 hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node) 598 #define sk_for_each_from(__sk, node) \ 599 if (__sk && ({ node = &(__sk)->sk_node; 1; })) \ 600 hlist_for_each_entry_from(__sk, node, sk_node) 601 #define sk_nulls_for_each_from(__sk, node) \ 602 if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \ 603 hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node) 604 #define sk_for_each_safe(__sk, node, tmp, list) \ 605 hlist_for_each_entry_safe(__sk, node, tmp, list, sk_node) 606 #define sk_for_each_bound(__sk, node, list) \ 607 hlist_for_each_entry(__sk, node, list, sk_bind_node) 608 609 static inline struct user_namespace *sk_user_ns(struct sock *sk) 610 { 611 /* Careful only use this in a context where these parameters 612 * can not change and must all be valid, such as recvmsg from 613 * userspace. 614 */ 615 return sk->sk_socket->file->f_cred->user_ns; 616 } 617 618 /* Sock flags */ 619 enum sock_flags { 620 SOCK_DEAD, 621 SOCK_DONE, 622 SOCK_URGINLINE, 623 SOCK_KEEPOPEN, 624 SOCK_LINGER, 625 SOCK_DESTROY, 626 SOCK_BROADCAST, 627 SOCK_TIMESTAMP, 628 SOCK_ZAPPED, 629 SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */ 630 SOCK_DBG, /* %SO_DEBUG setting */ 631 SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */ 632 SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */ 633 SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */ 634 SOCK_QUEUE_SHRUNK, /* write queue has been shrunk recently */ 635 SOCK_MEMALLOC, /* VM depends on this socket for swapping */ 636 SOCK_TIMESTAMPING_TX_HARDWARE, /* %SOF_TIMESTAMPING_TX_HARDWARE */ 637 SOCK_TIMESTAMPING_TX_SOFTWARE, /* %SOF_TIMESTAMPING_TX_SOFTWARE */ 638 SOCK_TIMESTAMPING_RX_HARDWARE, /* %SOF_TIMESTAMPING_RX_HARDWARE */ 639 SOCK_TIMESTAMPING_RX_SOFTWARE, /* %SOF_TIMESTAMPING_RX_SOFTWARE */ 640 SOCK_TIMESTAMPING_SOFTWARE, /* %SOF_TIMESTAMPING_SOFTWARE */ 641 SOCK_TIMESTAMPING_RAW_HARDWARE, /* %SOF_TIMESTAMPING_RAW_HARDWARE */ 642 SOCK_TIMESTAMPING_SYS_HARDWARE, /* %SOF_TIMESTAMPING_SYS_HARDWARE */ 643 SOCK_FASYNC, /* fasync() active */ 644 SOCK_RXQ_OVFL, 645 SOCK_ZEROCOPY, /* buffers from userspace */ 646 SOCK_WIFI_STATUS, /* push wifi status to userspace */ 647 SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS. 648 * Will use last 4 bytes of packet sent from 649 * user-space instead. 650 */ 651 }; 652 653 static inline void sock_copy_flags(struct sock *nsk, struct sock *osk) 654 { 655 nsk->sk_flags = osk->sk_flags; 656 } 657 658 static inline void sock_set_flag(struct sock *sk, enum sock_flags flag) 659 { 660 __set_bit(flag, &sk->sk_flags); 661 } 662 663 static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag) 664 { 665 __clear_bit(flag, &sk->sk_flags); 666 } 667 668 static inline bool sock_flag(const struct sock *sk, enum sock_flags flag) 669 { 670 return test_bit(flag, &sk->sk_flags); 671 } 672 673 #ifdef CONFIG_NET 674 extern struct static_key memalloc_socks; 675 static inline int sk_memalloc_socks(void) 676 { 677 return static_key_false(&memalloc_socks); 678 } 679 #else 680 681 static inline int sk_memalloc_socks(void) 682 { 683 return 0; 684 } 685 686 #endif 687 688 static inline gfp_t sk_gfp_atomic(struct sock *sk, gfp_t gfp_mask) 689 { 690 return GFP_ATOMIC | (sk->sk_allocation & __GFP_MEMALLOC); 691 } 692 693 static inline void sk_acceptq_removed(struct sock *sk) 694 { 695 sk->sk_ack_backlog--; 696 } 697 698 static inline void sk_acceptq_added(struct sock *sk) 699 { 700 sk->sk_ack_backlog++; 701 } 702 703 static inline bool sk_acceptq_is_full(const struct sock *sk) 704 { 705 return sk->sk_ack_backlog > sk->sk_max_ack_backlog; 706 } 707 708 /* 709 * Compute minimal free write space needed to queue new packets. 710 */ 711 static inline int sk_stream_min_wspace(const struct sock *sk) 712 { 713 return sk->sk_wmem_queued >> 1; 714 } 715 716 static inline int sk_stream_wspace(const struct sock *sk) 717 { 718 return sk->sk_sndbuf - sk->sk_wmem_queued; 719 } 720 721 extern void sk_stream_write_space(struct sock *sk); 722 723 static inline bool sk_stream_memory_free(const struct sock *sk) 724 { 725 return sk->sk_wmem_queued < sk->sk_sndbuf; 726 } 727 728 /* OOB backlog add */ 729 static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb) 730 { 731 /* dont let skb dst not refcounted, we are going to leave rcu lock */ 732 skb_dst_force(skb); 733 734 if (!sk->sk_backlog.tail) 735 sk->sk_backlog.head = skb; 736 else 737 sk->sk_backlog.tail->next = skb; 738 739 sk->sk_backlog.tail = skb; 740 skb->next = NULL; 741 } 742 743 /* 744 * Take into account size of receive queue and backlog queue 745 * Do not take into account this skb truesize, 746 * to allow even a single big packet to come. 747 */ 748 static inline bool sk_rcvqueues_full(const struct sock *sk, const struct sk_buff *skb, 749 unsigned int limit) 750 { 751 unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc); 752 753 return qsize > limit; 754 } 755 756 /* The per-socket spinlock must be held here. */ 757 static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb, 758 unsigned int limit) 759 { 760 if (sk_rcvqueues_full(sk, skb, limit)) 761 return -ENOBUFS; 762 763 __sk_add_backlog(sk, skb); 764 sk->sk_backlog.len += skb->truesize; 765 return 0; 766 } 767 768 extern int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb); 769 770 static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb) 771 { 772 if (sk_memalloc_socks() && skb_pfmemalloc(skb)) 773 return __sk_backlog_rcv(sk, skb); 774 775 return sk->sk_backlog_rcv(sk, skb); 776 } 777 778 static inline void sock_rps_record_flow(const struct sock *sk) 779 { 780 #ifdef CONFIG_RPS 781 struct rps_sock_flow_table *sock_flow_table; 782 783 rcu_read_lock(); 784 sock_flow_table = rcu_dereference(rps_sock_flow_table); 785 rps_record_sock_flow(sock_flow_table, sk->sk_rxhash); 786 rcu_read_unlock(); 787 #endif 788 } 789 790 static inline void sock_rps_reset_flow(const struct sock *sk) 791 { 792 #ifdef CONFIG_RPS 793 struct rps_sock_flow_table *sock_flow_table; 794 795 rcu_read_lock(); 796 sock_flow_table = rcu_dereference(rps_sock_flow_table); 797 rps_reset_sock_flow(sock_flow_table, sk->sk_rxhash); 798 rcu_read_unlock(); 799 #endif 800 } 801 802 static inline void sock_rps_save_rxhash(struct sock *sk, 803 const struct sk_buff *skb) 804 { 805 #ifdef CONFIG_RPS 806 if (unlikely(sk->sk_rxhash != skb->rxhash)) { 807 sock_rps_reset_flow(sk); 808 sk->sk_rxhash = skb->rxhash; 809 } 810 #endif 811 } 812 813 static inline void sock_rps_reset_rxhash(struct sock *sk) 814 { 815 #ifdef CONFIG_RPS 816 sock_rps_reset_flow(sk); 817 sk->sk_rxhash = 0; 818 #endif 819 } 820 821 #define sk_wait_event(__sk, __timeo, __condition) \ 822 ({ int __rc; \ 823 release_sock(__sk); \ 824 __rc = __condition; \ 825 if (!__rc) { \ 826 *(__timeo) = schedule_timeout(*(__timeo)); \ 827 } \ 828 lock_sock(__sk); \ 829 __rc = __condition; \ 830 __rc; \ 831 }) 832 833 extern int sk_stream_wait_connect(struct sock *sk, long *timeo_p); 834 extern int sk_stream_wait_memory(struct sock *sk, long *timeo_p); 835 extern void sk_stream_wait_close(struct sock *sk, long timeo_p); 836 extern int sk_stream_error(struct sock *sk, int flags, int err); 837 extern void sk_stream_kill_queues(struct sock *sk); 838 extern void sk_set_memalloc(struct sock *sk); 839 extern void sk_clear_memalloc(struct sock *sk); 840 841 extern int sk_wait_data(struct sock *sk, long *timeo); 842 843 struct request_sock_ops; 844 struct timewait_sock_ops; 845 struct inet_hashinfo; 846 struct raw_hashinfo; 847 struct module; 848 849 /* Networking protocol blocks we attach to sockets. 850 * socket layer -> transport layer interface 851 * transport -> network interface is defined by struct inet_proto 852 */ 853 struct proto { 854 void (*close)(struct sock *sk, 855 long timeout); 856 int (*connect)(struct sock *sk, 857 struct sockaddr *uaddr, 858 int addr_len); 859 int (*disconnect)(struct sock *sk, int flags); 860 861 struct sock * (*accept)(struct sock *sk, int flags, int *err); 862 863 int (*ioctl)(struct sock *sk, int cmd, 864 unsigned long arg); 865 int (*init)(struct sock *sk); 866 void (*destroy)(struct sock *sk); 867 void (*shutdown)(struct sock *sk, int how); 868 int (*setsockopt)(struct sock *sk, int level, 869 int optname, char __user *optval, 870 unsigned int optlen); 871 int (*getsockopt)(struct sock *sk, int level, 872 int optname, char __user *optval, 873 int __user *option); 874 #ifdef CONFIG_COMPAT 875 int (*compat_setsockopt)(struct sock *sk, 876 int level, 877 int optname, char __user *optval, 878 unsigned int optlen); 879 int (*compat_getsockopt)(struct sock *sk, 880 int level, 881 int optname, char __user *optval, 882 int __user *option); 883 int (*compat_ioctl)(struct sock *sk, 884 unsigned int cmd, unsigned long arg); 885 #endif 886 int (*sendmsg)(struct kiocb *iocb, struct sock *sk, 887 struct msghdr *msg, size_t len); 888 int (*recvmsg)(struct kiocb *iocb, struct sock *sk, 889 struct msghdr *msg, 890 size_t len, int noblock, int flags, 891 int *addr_len); 892 int (*sendpage)(struct sock *sk, struct page *page, 893 int offset, size_t size, int flags); 894 int (*bind)(struct sock *sk, 895 struct sockaddr *uaddr, int addr_len); 896 897 int (*backlog_rcv) (struct sock *sk, 898 struct sk_buff *skb); 899 900 void (*release_cb)(struct sock *sk); 901 void (*mtu_reduced)(struct sock *sk); 902 903 /* Keeping track of sk's, looking them up, and port selection methods. */ 904 void (*hash)(struct sock *sk); 905 void (*unhash)(struct sock *sk); 906 void (*rehash)(struct sock *sk); 907 int (*get_port)(struct sock *sk, unsigned short snum); 908 void (*clear_sk)(struct sock *sk, int size); 909 910 /* Keeping track of sockets in use */ 911 #ifdef CONFIG_PROC_FS 912 unsigned int inuse_idx; 913 #endif 914 915 /* Memory pressure */ 916 void (*enter_memory_pressure)(struct sock *sk); 917 atomic_long_t *memory_allocated; /* Current allocated memory. */ 918 struct percpu_counter *sockets_allocated; /* Current number of sockets. */ 919 /* 920 * Pressure flag: try to collapse. 921 * Technical note: it is used by multiple contexts non atomically. 922 * All the __sk_mem_schedule() is of this nature: accounting 923 * is strict, actions are advisory and have some latency. 924 */ 925 int *memory_pressure; 926 long *sysctl_mem; 927 int *sysctl_wmem; 928 int *sysctl_rmem; 929 int max_header; 930 bool no_autobind; 931 932 struct kmem_cache *slab; 933 unsigned int obj_size; 934 int slab_flags; 935 936 struct percpu_counter *orphan_count; 937 938 struct request_sock_ops *rsk_prot; 939 struct timewait_sock_ops *twsk_prot; 940 941 union { 942 struct inet_hashinfo *hashinfo; 943 struct udp_table *udp_table; 944 struct raw_hashinfo *raw_hash; 945 } h; 946 947 struct module *owner; 948 949 char name[32]; 950 951 struct list_head node; 952 #ifdef SOCK_REFCNT_DEBUG 953 atomic_t socks; 954 #endif 955 #ifdef CONFIG_MEMCG_KMEM 956 /* 957 * cgroup specific init/deinit functions. Called once for all 958 * protocols that implement it, from cgroups populate function. 959 * This function has to setup any files the protocol want to 960 * appear in the kmem cgroup filesystem. 961 */ 962 int (*init_cgroup)(struct mem_cgroup *memcg, 963 struct cgroup_subsys *ss); 964 void (*destroy_cgroup)(struct mem_cgroup *memcg); 965 struct cg_proto *(*proto_cgroup)(struct mem_cgroup *memcg); 966 #endif 967 }; 968 969 /* 970 * Bits in struct cg_proto.flags 971 */ 972 enum cg_proto_flags { 973 /* Currently active and new sockets should be assigned to cgroups */ 974 MEMCG_SOCK_ACTIVE, 975 /* It was ever activated; we must disarm static keys on destruction */ 976 MEMCG_SOCK_ACTIVATED, 977 }; 978 979 struct cg_proto { 980 void (*enter_memory_pressure)(struct sock *sk); 981 struct res_counter *memory_allocated; /* Current allocated memory. */ 982 struct percpu_counter *sockets_allocated; /* Current number of sockets. */ 983 int *memory_pressure; 984 long *sysctl_mem; 985 unsigned long flags; 986 /* 987 * memcg field is used to find which memcg we belong directly 988 * Each memcg struct can hold more than one cg_proto, so container_of 989 * won't really cut. 990 * 991 * The elegant solution would be having an inverse function to 992 * proto_cgroup in struct proto, but that means polluting the structure 993 * for everybody, instead of just for memcg users. 994 */ 995 struct mem_cgroup *memcg; 996 }; 997 998 extern int proto_register(struct proto *prot, int alloc_slab); 999 extern void proto_unregister(struct proto *prot); 1000 1001 static inline bool memcg_proto_active(struct cg_proto *cg_proto) 1002 { 1003 return test_bit(MEMCG_SOCK_ACTIVE, &cg_proto->flags); 1004 } 1005 1006 static inline bool memcg_proto_activated(struct cg_proto *cg_proto) 1007 { 1008 return test_bit(MEMCG_SOCK_ACTIVATED, &cg_proto->flags); 1009 } 1010 1011 #ifdef SOCK_REFCNT_DEBUG 1012 static inline void sk_refcnt_debug_inc(struct sock *sk) 1013 { 1014 atomic_inc(&sk->sk_prot->socks); 1015 } 1016 1017 static inline void sk_refcnt_debug_dec(struct sock *sk) 1018 { 1019 atomic_dec(&sk->sk_prot->socks); 1020 printk(KERN_DEBUG "%s socket %p released, %d are still alive\n", 1021 sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks)); 1022 } 1023 1024 inline void sk_refcnt_debug_release(const struct sock *sk) 1025 { 1026 if (atomic_read(&sk->sk_refcnt) != 1) 1027 printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n", 1028 sk->sk_prot->name, sk, atomic_read(&sk->sk_refcnt)); 1029 } 1030 #else /* SOCK_REFCNT_DEBUG */ 1031 #define sk_refcnt_debug_inc(sk) do { } while (0) 1032 #define sk_refcnt_debug_dec(sk) do { } while (0) 1033 #define sk_refcnt_debug_release(sk) do { } while (0) 1034 #endif /* SOCK_REFCNT_DEBUG */ 1035 1036 #if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_NET) 1037 extern struct static_key memcg_socket_limit_enabled; 1038 static inline struct cg_proto *parent_cg_proto(struct proto *proto, 1039 struct cg_proto *cg_proto) 1040 { 1041 return proto->proto_cgroup(parent_mem_cgroup(cg_proto->memcg)); 1042 } 1043 #define mem_cgroup_sockets_enabled static_key_false(&memcg_socket_limit_enabled) 1044 #else 1045 #define mem_cgroup_sockets_enabled 0 1046 static inline struct cg_proto *parent_cg_proto(struct proto *proto, 1047 struct cg_proto *cg_proto) 1048 { 1049 return NULL; 1050 } 1051 #endif 1052 1053 1054 static inline bool sk_has_memory_pressure(const struct sock *sk) 1055 { 1056 return sk->sk_prot->memory_pressure != NULL; 1057 } 1058 1059 static inline bool sk_under_memory_pressure(const struct sock *sk) 1060 { 1061 if (!sk->sk_prot->memory_pressure) 1062 return false; 1063 1064 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) 1065 return !!*sk->sk_cgrp->memory_pressure; 1066 1067 return !!*sk->sk_prot->memory_pressure; 1068 } 1069 1070 static inline void sk_leave_memory_pressure(struct sock *sk) 1071 { 1072 int *memory_pressure = sk->sk_prot->memory_pressure; 1073 1074 if (!memory_pressure) 1075 return; 1076 1077 if (*memory_pressure) 1078 *memory_pressure = 0; 1079 1080 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) { 1081 struct cg_proto *cg_proto = sk->sk_cgrp; 1082 struct proto *prot = sk->sk_prot; 1083 1084 for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto)) 1085 if (*cg_proto->memory_pressure) 1086 *cg_proto->memory_pressure = 0; 1087 } 1088 1089 } 1090 1091 static inline void sk_enter_memory_pressure(struct sock *sk) 1092 { 1093 if (!sk->sk_prot->enter_memory_pressure) 1094 return; 1095 1096 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) { 1097 struct cg_proto *cg_proto = sk->sk_cgrp; 1098 struct proto *prot = sk->sk_prot; 1099 1100 for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto)) 1101 cg_proto->enter_memory_pressure(sk); 1102 } 1103 1104 sk->sk_prot->enter_memory_pressure(sk); 1105 } 1106 1107 static inline long sk_prot_mem_limits(const struct sock *sk, int index) 1108 { 1109 long *prot = sk->sk_prot->sysctl_mem; 1110 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) 1111 prot = sk->sk_cgrp->sysctl_mem; 1112 return prot[index]; 1113 } 1114 1115 static inline void memcg_memory_allocated_add(struct cg_proto *prot, 1116 unsigned long amt, 1117 int *parent_status) 1118 { 1119 struct res_counter *fail; 1120 int ret; 1121 1122 ret = res_counter_charge_nofail(prot->memory_allocated, 1123 amt << PAGE_SHIFT, &fail); 1124 if (ret < 0) 1125 *parent_status = OVER_LIMIT; 1126 } 1127 1128 static inline void memcg_memory_allocated_sub(struct cg_proto *prot, 1129 unsigned long amt) 1130 { 1131 res_counter_uncharge(prot->memory_allocated, amt << PAGE_SHIFT); 1132 } 1133 1134 static inline u64 memcg_memory_allocated_read(struct cg_proto *prot) 1135 { 1136 u64 ret; 1137 ret = res_counter_read_u64(prot->memory_allocated, RES_USAGE); 1138 return ret >> PAGE_SHIFT; 1139 } 1140 1141 static inline long 1142 sk_memory_allocated(const struct sock *sk) 1143 { 1144 struct proto *prot = sk->sk_prot; 1145 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) 1146 return memcg_memory_allocated_read(sk->sk_cgrp); 1147 1148 return atomic_long_read(prot->memory_allocated); 1149 } 1150 1151 static inline long 1152 sk_memory_allocated_add(struct sock *sk, int amt, int *parent_status) 1153 { 1154 struct proto *prot = sk->sk_prot; 1155 1156 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) { 1157 memcg_memory_allocated_add(sk->sk_cgrp, amt, parent_status); 1158 /* update the root cgroup regardless */ 1159 atomic_long_add_return(amt, prot->memory_allocated); 1160 return memcg_memory_allocated_read(sk->sk_cgrp); 1161 } 1162 1163 return atomic_long_add_return(amt, prot->memory_allocated); 1164 } 1165 1166 static inline void 1167 sk_memory_allocated_sub(struct sock *sk, int amt) 1168 { 1169 struct proto *prot = sk->sk_prot; 1170 1171 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) 1172 memcg_memory_allocated_sub(sk->sk_cgrp, amt); 1173 1174 atomic_long_sub(amt, prot->memory_allocated); 1175 } 1176 1177 static inline void sk_sockets_allocated_dec(struct sock *sk) 1178 { 1179 struct proto *prot = sk->sk_prot; 1180 1181 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) { 1182 struct cg_proto *cg_proto = sk->sk_cgrp; 1183 1184 for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto)) 1185 percpu_counter_dec(cg_proto->sockets_allocated); 1186 } 1187 1188 percpu_counter_dec(prot->sockets_allocated); 1189 } 1190 1191 static inline void sk_sockets_allocated_inc(struct sock *sk) 1192 { 1193 struct proto *prot = sk->sk_prot; 1194 1195 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) { 1196 struct cg_proto *cg_proto = sk->sk_cgrp; 1197 1198 for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto)) 1199 percpu_counter_inc(cg_proto->sockets_allocated); 1200 } 1201 1202 percpu_counter_inc(prot->sockets_allocated); 1203 } 1204 1205 static inline int 1206 sk_sockets_allocated_read_positive(struct sock *sk) 1207 { 1208 struct proto *prot = sk->sk_prot; 1209 1210 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) 1211 return percpu_counter_read_positive(sk->sk_cgrp->sockets_allocated); 1212 1213 return percpu_counter_read_positive(prot->sockets_allocated); 1214 } 1215 1216 static inline int 1217 proto_sockets_allocated_sum_positive(struct proto *prot) 1218 { 1219 return percpu_counter_sum_positive(prot->sockets_allocated); 1220 } 1221 1222 static inline long 1223 proto_memory_allocated(struct proto *prot) 1224 { 1225 return atomic_long_read(prot->memory_allocated); 1226 } 1227 1228 static inline bool 1229 proto_memory_pressure(struct proto *prot) 1230 { 1231 if (!prot->memory_pressure) 1232 return false; 1233 return !!*prot->memory_pressure; 1234 } 1235 1236 1237 #ifdef CONFIG_PROC_FS 1238 /* Called with local bh disabled */ 1239 extern void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc); 1240 extern int sock_prot_inuse_get(struct net *net, struct proto *proto); 1241 #else 1242 static inline void sock_prot_inuse_add(struct net *net, struct proto *prot, 1243 int inc) 1244 { 1245 } 1246 #endif 1247 1248 1249 /* With per-bucket locks this operation is not-atomic, so that 1250 * this version is not worse. 1251 */ 1252 static inline void __sk_prot_rehash(struct sock *sk) 1253 { 1254 sk->sk_prot->unhash(sk); 1255 sk->sk_prot->hash(sk); 1256 } 1257 1258 void sk_prot_clear_portaddr_nulls(struct sock *sk, int size); 1259 1260 /* About 10 seconds */ 1261 #define SOCK_DESTROY_TIME (10*HZ) 1262 1263 /* Sockets 0-1023 can't be bound to unless you are superuser */ 1264 #define PROT_SOCK 1024 1265 1266 #define SHUTDOWN_MASK 3 1267 #define RCV_SHUTDOWN 1 1268 #define SEND_SHUTDOWN 2 1269 1270 #define SOCK_SNDBUF_LOCK 1 1271 #define SOCK_RCVBUF_LOCK 2 1272 #define SOCK_BINDADDR_LOCK 4 1273 #define SOCK_BINDPORT_LOCK 8 1274 1275 /* sock_iocb: used to kick off async processing of socket ios */ 1276 struct sock_iocb { 1277 struct list_head list; 1278 1279 int flags; 1280 int size; 1281 struct socket *sock; 1282 struct sock *sk; 1283 struct scm_cookie *scm; 1284 struct msghdr *msg, async_msg; 1285 struct kiocb *kiocb; 1286 }; 1287 1288 static inline struct sock_iocb *kiocb_to_siocb(struct kiocb *iocb) 1289 { 1290 return (struct sock_iocb *)iocb->private; 1291 } 1292 1293 static inline struct kiocb *siocb_to_kiocb(struct sock_iocb *si) 1294 { 1295 return si->kiocb; 1296 } 1297 1298 struct socket_alloc { 1299 struct socket socket; 1300 struct inode vfs_inode; 1301 }; 1302 1303 static inline struct socket *SOCKET_I(struct inode *inode) 1304 { 1305 return &container_of(inode, struct socket_alloc, vfs_inode)->socket; 1306 } 1307 1308 static inline struct inode *SOCK_INODE(struct socket *socket) 1309 { 1310 return &container_of(socket, struct socket_alloc, socket)->vfs_inode; 1311 } 1312 1313 /* 1314 * Functions for memory accounting 1315 */ 1316 extern int __sk_mem_schedule(struct sock *sk, int size, int kind); 1317 extern void __sk_mem_reclaim(struct sock *sk); 1318 1319 #define SK_MEM_QUANTUM ((int)PAGE_SIZE) 1320 #define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM) 1321 #define SK_MEM_SEND 0 1322 #define SK_MEM_RECV 1 1323 1324 static inline int sk_mem_pages(int amt) 1325 { 1326 return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT; 1327 } 1328 1329 static inline bool sk_has_account(struct sock *sk) 1330 { 1331 /* return true if protocol supports memory accounting */ 1332 return !!sk->sk_prot->memory_allocated; 1333 } 1334 1335 static inline bool sk_wmem_schedule(struct sock *sk, int size) 1336 { 1337 if (!sk_has_account(sk)) 1338 return true; 1339 return size <= sk->sk_forward_alloc || 1340 __sk_mem_schedule(sk, size, SK_MEM_SEND); 1341 } 1342 1343 static inline bool 1344 sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, unsigned int size) 1345 { 1346 if (!sk_has_account(sk)) 1347 return true; 1348 return size<= sk->sk_forward_alloc || 1349 __sk_mem_schedule(sk, size, SK_MEM_RECV) || 1350 skb_pfmemalloc(skb); 1351 } 1352 1353 static inline void sk_mem_reclaim(struct sock *sk) 1354 { 1355 if (!sk_has_account(sk)) 1356 return; 1357 if (sk->sk_forward_alloc >= SK_MEM_QUANTUM) 1358 __sk_mem_reclaim(sk); 1359 } 1360 1361 static inline void sk_mem_reclaim_partial(struct sock *sk) 1362 { 1363 if (!sk_has_account(sk)) 1364 return; 1365 if (sk->sk_forward_alloc > SK_MEM_QUANTUM) 1366 __sk_mem_reclaim(sk); 1367 } 1368 1369 static inline void sk_mem_charge(struct sock *sk, int size) 1370 { 1371 if (!sk_has_account(sk)) 1372 return; 1373 sk->sk_forward_alloc -= size; 1374 } 1375 1376 static inline void sk_mem_uncharge(struct sock *sk, int size) 1377 { 1378 if (!sk_has_account(sk)) 1379 return; 1380 sk->sk_forward_alloc += size; 1381 } 1382 1383 static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb) 1384 { 1385 sock_set_flag(sk, SOCK_QUEUE_SHRUNK); 1386 sk->sk_wmem_queued -= skb->truesize; 1387 sk_mem_uncharge(sk, skb->truesize); 1388 __kfree_skb(skb); 1389 } 1390 1391 /* Used by processes to "lock" a socket state, so that 1392 * interrupts and bottom half handlers won't change it 1393 * from under us. It essentially blocks any incoming 1394 * packets, so that we won't get any new data or any 1395 * packets that change the state of the socket. 1396 * 1397 * While locked, BH processing will add new packets to 1398 * the backlog queue. This queue is processed by the 1399 * owner of the socket lock right before it is released. 1400 * 1401 * Since ~2.3.5 it is also exclusive sleep lock serializing 1402 * accesses from user process context. 1403 */ 1404 #define sock_owned_by_user(sk) ((sk)->sk_lock.owned) 1405 1406 /* 1407 * Macro so as to not evaluate some arguments when 1408 * lockdep is not enabled. 1409 * 1410 * Mark both the sk_lock and the sk_lock.slock as a 1411 * per-address-family lock class. 1412 */ 1413 #define sock_lock_init_class_and_name(sk, sname, skey, name, key) \ 1414 do { \ 1415 sk->sk_lock.owned = 0; \ 1416 init_waitqueue_head(&sk->sk_lock.wq); \ 1417 spin_lock_init(&(sk)->sk_lock.slock); \ 1418 debug_check_no_locks_freed((void *)&(sk)->sk_lock, \ 1419 sizeof((sk)->sk_lock)); \ 1420 lockdep_set_class_and_name(&(sk)->sk_lock.slock, \ 1421 (skey), (sname)); \ 1422 lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \ 1423 } while (0) 1424 1425 extern void lock_sock_nested(struct sock *sk, int subclass); 1426 1427 static inline void lock_sock(struct sock *sk) 1428 { 1429 lock_sock_nested(sk, 0); 1430 } 1431 1432 extern void release_sock(struct sock *sk); 1433 1434 /* BH context may only use the following locking interface. */ 1435 #define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock)) 1436 #define bh_lock_sock_nested(__sk) \ 1437 spin_lock_nested(&((__sk)->sk_lock.slock), \ 1438 SINGLE_DEPTH_NESTING) 1439 #define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock)) 1440 1441 extern bool lock_sock_fast(struct sock *sk); 1442 /** 1443 * unlock_sock_fast - complement of lock_sock_fast 1444 * @sk: socket 1445 * @slow: slow mode 1446 * 1447 * fast unlock socket for user context. 1448 * If slow mode is on, we call regular release_sock() 1449 */ 1450 static inline void unlock_sock_fast(struct sock *sk, bool slow) 1451 { 1452 if (slow) 1453 release_sock(sk); 1454 else 1455 spin_unlock_bh(&sk->sk_lock.slock); 1456 } 1457 1458 1459 extern struct sock *sk_alloc(struct net *net, int family, 1460 gfp_t priority, 1461 struct proto *prot); 1462 extern void sk_free(struct sock *sk); 1463 extern void sk_release_kernel(struct sock *sk); 1464 extern struct sock *sk_clone_lock(const struct sock *sk, 1465 const gfp_t priority); 1466 1467 extern struct sk_buff *sock_wmalloc(struct sock *sk, 1468 unsigned long size, int force, 1469 gfp_t priority); 1470 extern struct sk_buff *sock_rmalloc(struct sock *sk, 1471 unsigned long size, int force, 1472 gfp_t priority); 1473 extern void sock_wfree(struct sk_buff *skb); 1474 extern void sock_rfree(struct sk_buff *skb); 1475 extern void sock_edemux(struct sk_buff *skb); 1476 1477 extern int sock_setsockopt(struct socket *sock, int level, 1478 int op, char __user *optval, 1479 unsigned int optlen); 1480 1481 extern int sock_getsockopt(struct socket *sock, int level, 1482 int op, char __user *optval, 1483 int __user *optlen); 1484 extern struct sk_buff *sock_alloc_send_skb(struct sock *sk, 1485 unsigned long size, 1486 int noblock, 1487 int *errcode); 1488 extern struct sk_buff *sock_alloc_send_pskb(struct sock *sk, 1489 unsigned long header_len, 1490 unsigned long data_len, 1491 int noblock, 1492 int *errcode); 1493 extern void *sock_kmalloc(struct sock *sk, int size, 1494 gfp_t priority); 1495 extern void sock_kfree_s(struct sock *sk, void *mem, int size); 1496 extern void sk_send_sigurg(struct sock *sk); 1497 1498 #ifdef CONFIG_CGROUPS 1499 extern void sock_update_classid(struct sock *sk); 1500 #else 1501 static inline void sock_update_classid(struct sock *sk) 1502 { 1503 } 1504 #endif 1505 1506 /* 1507 * Functions to fill in entries in struct proto_ops when a protocol 1508 * does not implement a particular function. 1509 */ 1510 extern int sock_no_bind(struct socket *, 1511 struct sockaddr *, int); 1512 extern int sock_no_connect(struct socket *, 1513 struct sockaddr *, int, int); 1514 extern int sock_no_socketpair(struct socket *, 1515 struct socket *); 1516 extern int sock_no_accept(struct socket *, 1517 struct socket *, int); 1518 extern int sock_no_getname(struct socket *, 1519 struct sockaddr *, int *, int); 1520 extern unsigned int sock_no_poll(struct file *, struct socket *, 1521 struct poll_table_struct *); 1522 extern int sock_no_ioctl(struct socket *, unsigned int, 1523 unsigned long); 1524 extern int sock_no_listen(struct socket *, int); 1525 extern int sock_no_shutdown(struct socket *, int); 1526 extern int sock_no_getsockopt(struct socket *, int , int, 1527 char __user *, int __user *); 1528 extern int sock_no_setsockopt(struct socket *, int, int, 1529 char __user *, unsigned int); 1530 extern int sock_no_sendmsg(struct kiocb *, struct socket *, 1531 struct msghdr *, size_t); 1532 extern int sock_no_recvmsg(struct kiocb *, struct socket *, 1533 struct msghdr *, size_t, int); 1534 extern int sock_no_mmap(struct file *file, 1535 struct socket *sock, 1536 struct vm_area_struct *vma); 1537 extern ssize_t sock_no_sendpage(struct socket *sock, 1538 struct page *page, 1539 int offset, size_t size, 1540 int flags); 1541 1542 /* 1543 * Functions to fill in entries in struct proto_ops when a protocol 1544 * uses the inet style. 1545 */ 1546 extern int sock_common_getsockopt(struct socket *sock, int level, int optname, 1547 char __user *optval, int __user *optlen); 1548 extern int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock, 1549 struct msghdr *msg, size_t size, int flags); 1550 extern int sock_common_setsockopt(struct socket *sock, int level, int optname, 1551 char __user *optval, unsigned int optlen); 1552 extern int compat_sock_common_getsockopt(struct socket *sock, int level, 1553 int optname, char __user *optval, int __user *optlen); 1554 extern int compat_sock_common_setsockopt(struct socket *sock, int level, 1555 int optname, char __user *optval, unsigned int optlen); 1556 1557 extern void sk_common_release(struct sock *sk); 1558 1559 /* 1560 * Default socket callbacks and setup code 1561 */ 1562 1563 /* Initialise core socket variables */ 1564 extern void sock_init_data(struct socket *sock, struct sock *sk); 1565 1566 extern void sk_filter_release_rcu(struct rcu_head *rcu); 1567 1568 /** 1569 * sk_filter_release - release a socket filter 1570 * @fp: filter to remove 1571 * 1572 * Remove a filter from a socket and release its resources. 1573 */ 1574 1575 static inline void sk_filter_release(struct sk_filter *fp) 1576 { 1577 if (atomic_dec_and_test(&fp->refcnt)) 1578 call_rcu(&fp->rcu, sk_filter_release_rcu); 1579 } 1580 1581 static inline void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp) 1582 { 1583 unsigned int size = sk_filter_len(fp); 1584 1585 atomic_sub(size, &sk->sk_omem_alloc); 1586 sk_filter_release(fp); 1587 } 1588 1589 static inline void sk_filter_charge(struct sock *sk, struct sk_filter *fp) 1590 { 1591 atomic_inc(&fp->refcnt); 1592 atomic_add(sk_filter_len(fp), &sk->sk_omem_alloc); 1593 } 1594 1595 /* 1596 * Socket reference counting postulates. 1597 * 1598 * * Each user of socket SHOULD hold a reference count. 1599 * * Each access point to socket (an hash table bucket, reference from a list, 1600 * running timer, skb in flight MUST hold a reference count. 1601 * * When reference count hits 0, it means it will never increase back. 1602 * * When reference count hits 0, it means that no references from 1603 * outside exist to this socket and current process on current CPU 1604 * is last user and may/should destroy this socket. 1605 * * sk_free is called from any context: process, BH, IRQ. When 1606 * it is called, socket has no references from outside -> sk_free 1607 * may release descendant resources allocated by the socket, but 1608 * to the time when it is called, socket is NOT referenced by any 1609 * hash tables, lists etc. 1610 * * Packets, delivered from outside (from network or from another process) 1611 * and enqueued on receive/error queues SHOULD NOT grab reference count, 1612 * when they sit in queue. Otherwise, packets will leak to hole, when 1613 * socket is looked up by one cpu and unhasing is made by another CPU. 1614 * It is true for udp/raw, netlink (leak to receive and error queues), tcp 1615 * (leak to backlog). Packet socket does all the processing inside 1616 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets 1617 * use separate SMP lock, so that they are prone too. 1618 */ 1619 1620 /* Ungrab socket and destroy it, if it was the last reference. */ 1621 static inline void sock_put(struct sock *sk) 1622 { 1623 if (atomic_dec_and_test(&sk->sk_refcnt)) 1624 sk_free(sk); 1625 } 1626 1627 extern int sk_receive_skb(struct sock *sk, struct sk_buff *skb, 1628 const int nested); 1629 1630 static inline void sk_tx_queue_set(struct sock *sk, int tx_queue) 1631 { 1632 sk->sk_tx_queue_mapping = tx_queue; 1633 } 1634 1635 static inline void sk_tx_queue_clear(struct sock *sk) 1636 { 1637 sk->sk_tx_queue_mapping = -1; 1638 } 1639 1640 static inline int sk_tx_queue_get(const struct sock *sk) 1641 { 1642 return sk ? sk->sk_tx_queue_mapping : -1; 1643 } 1644 1645 static inline void sk_set_socket(struct sock *sk, struct socket *sock) 1646 { 1647 sk_tx_queue_clear(sk); 1648 sk->sk_socket = sock; 1649 } 1650 1651 static inline wait_queue_head_t *sk_sleep(struct sock *sk) 1652 { 1653 BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0); 1654 return &rcu_dereference_raw(sk->sk_wq)->wait; 1655 } 1656 /* Detach socket from process context. 1657 * Announce socket dead, detach it from wait queue and inode. 1658 * Note that parent inode held reference count on this struct sock, 1659 * we do not release it in this function, because protocol 1660 * probably wants some additional cleanups or even continuing 1661 * to work with this socket (TCP). 1662 */ 1663 static inline void sock_orphan(struct sock *sk) 1664 { 1665 write_lock_bh(&sk->sk_callback_lock); 1666 sock_set_flag(sk, SOCK_DEAD); 1667 sk_set_socket(sk, NULL); 1668 sk->sk_wq = NULL; 1669 write_unlock_bh(&sk->sk_callback_lock); 1670 } 1671 1672 static inline void sock_graft(struct sock *sk, struct socket *parent) 1673 { 1674 write_lock_bh(&sk->sk_callback_lock); 1675 sk->sk_wq = parent->wq; 1676 parent->sk = sk; 1677 sk_set_socket(sk, parent); 1678 security_sock_graft(sk, parent); 1679 write_unlock_bh(&sk->sk_callback_lock); 1680 } 1681 1682 extern kuid_t sock_i_uid(struct sock *sk); 1683 extern unsigned long sock_i_ino(struct sock *sk); 1684 1685 static inline struct dst_entry * 1686 __sk_dst_get(struct sock *sk) 1687 { 1688 return rcu_dereference_check(sk->sk_dst_cache, sock_owned_by_user(sk) || 1689 lockdep_is_held(&sk->sk_lock.slock)); 1690 } 1691 1692 static inline struct dst_entry * 1693 sk_dst_get(struct sock *sk) 1694 { 1695 struct dst_entry *dst; 1696 1697 rcu_read_lock(); 1698 dst = rcu_dereference(sk->sk_dst_cache); 1699 if (dst) 1700 dst_hold(dst); 1701 rcu_read_unlock(); 1702 return dst; 1703 } 1704 1705 extern void sk_reset_txq(struct sock *sk); 1706 1707 static inline void dst_negative_advice(struct sock *sk) 1708 { 1709 struct dst_entry *ndst, *dst = __sk_dst_get(sk); 1710 1711 if (dst && dst->ops->negative_advice) { 1712 ndst = dst->ops->negative_advice(dst); 1713 1714 if (ndst != dst) { 1715 rcu_assign_pointer(sk->sk_dst_cache, ndst); 1716 sk_reset_txq(sk); 1717 } 1718 } 1719 } 1720 1721 static inline void 1722 __sk_dst_set(struct sock *sk, struct dst_entry *dst) 1723 { 1724 struct dst_entry *old_dst; 1725 1726 sk_tx_queue_clear(sk); 1727 /* 1728 * This can be called while sk is owned by the caller only, 1729 * with no state that can be checked in a rcu_dereference_check() cond 1730 */ 1731 old_dst = rcu_dereference_raw(sk->sk_dst_cache); 1732 rcu_assign_pointer(sk->sk_dst_cache, dst); 1733 dst_release(old_dst); 1734 } 1735 1736 static inline void 1737 sk_dst_set(struct sock *sk, struct dst_entry *dst) 1738 { 1739 spin_lock(&sk->sk_dst_lock); 1740 __sk_dst_set(sk, dst); 1741 spin_unlock(&sk->sk_dst_lock); 1742 } 1743 1744 static inline void 1745 __sk_dst_reset(struct sock *sk) 1746 { 1747 __sk_dst_set(sk, NULL); 1748 } 1749 1750 static inline void 1751 sk_dst_reset(struct sock *sk) 1752 { 1753 spin_lock(&sk->sk_dst_lock); 1754 __sk_dst_reset(sk); 1755 spin_unlock(&sk->sk_dst_lock); 1756 } 1757 1758 extern struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie); 1759 1760 extern struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie); 1761 1762 static inline bool sk_can_gso(const struct sock *sk) 1763 { 1764 return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type); 1765 } 1766 1767 extern void sk_setup_caps(struct sock *sk, struct dst_entry *dst); 1768 1769 static inline void sk_nocaps_add(struct sock *sk, netdev_features_t flags) 1770 { 1771 sk->sk_route_nocaps |= flags; 1772 sk->sk_route_caps &= ~flags; 1773 } 1774 1775 static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb, 1776 char __user *from, char *to, 1777 int copy, int offset) 1778 { 1779 if (skb->ip_summed == CHECKSUM_NONE) { 1780 int err = 0; 1781 __wsum csum = csum_and_copy_from_user(from, to, copy, 0, &err); 1782 if (err) 1783 return err; 1784 skb->csum = csum_block_add(skb->csum, csum, offset); 1785 } else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) { 1786 if (!access_ok(VERIFY_READ, from, copy) || 1787 __copy_from_user_nocache(to, from, copy)) 1788 return -EFAULT; 1789 } else if (copy_from_user(to, from, copy)) 1790 return -EFAULT; 1791 1792 return 0; 1793 } 1794 1795 static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb, 1796 char __user *from, int copy) 1797 { 1798 int err, offset = skb->len; 1799 1800 err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy), 1801 copy, offset); 1802 if (err) 1803 __skb_trim(skb, offset); 1804 1805 return err; 1806 } 1807 1808 static inline int skb_copy_to_page_nocache(struct sock *sk, char __user *from, 1809 struct sk_buff *skb, 1810 struct page *page, 1811 int off, int copy) 1812 { 1813 int err; 1814 1815 err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off, 1816 copy, skb->len); 1817 if (err) 1818 return err; 1819 1820 skb->len += copy; 1821 skb->data_len += copy; 1822 skb->truesize += copy; 1823 sk->sk_wmem_queued += copy; 1824 sk_mem_charge(sk, copy); 1825 return 0; 1826 } 1827 1828 static inline int skb_copy_to_page(struct sock *sk, char __user *from, 1829 struct sk_buff *skb, struct page *page, 1830 int off, int copy) 1831 { 1832 if (skb->ip_summed == CHECKSUM_NONE) { 1833 int err = 0; 1834 __wsum csum = csum_and_copy_from_user(from, 1835 page_address(page) + off, 1836 copy, 0, &err); 1837 if (err) 1838 return err; 1839 skb->csum = csum_block_add(skb->csum, csum, skb->len); 1840 } else if (copy_from_user(page_address(page) + off, from, copy)) 1841 return -EFAULT; 1842 1843 skb->len += copy; 1844 skb->data_len += copy; 1845 skb->truesize += copy; 1846 sk->sk_wmem_queued += copy; 1847 sk_mem_charge(sk, copy); 1848 return 0; 1849 } 1850 1851 /** 1852 * sk_wmem_alloc_get - returns write allocations 1853 * @sk: socket 1854 * 1855 * Returns sk_wmem_alloc minus initial offset of one 1856 */ 1857 static inline int sk_wmem_alloc_get(const struct sock *sk) 1858 { 1859 return atomic_read(&sk->sk_wmem_alloc) - 1; 1860 } 1861 1862 /** 1863 * sk_rmem_alloc_get - returns read allocations 1864 * @sk: socket 1865 * 1866 * Returns sk_rmem_alloc 1867 */ 1868 static inline int sk_rmem_alloc_get(const struct sock *sk) 1869 { 1870 return atomic_read(&sk->sk_rmem_alloc); 1871 } 1872 1873 /** 1874 * sk_has_allocations - check if allocations are outstanding 1875 * @sk: socket 1876 * 1877 * Returns true if socket has write or read allocations 1878 */ 1879 static inline bool sk_has_allocations(const struct sock *sk) 1880 { 1881 return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk); 1882 } 1883 1884 /** 1885 * wq_has_sleeper - check if there are any waiting processes 1886 * @wq: struct socket_wq 1887 * 1888 * Returns true if socket_wq has waiting processes 1889 * 1890 * The purpose of the wq_has_sleeper and sock_poll_wait is to wrap the memory 1891 * barrier call. They were added due to the race found within the tcp code. 1892 * 1893 * Consider following tcp code paths: 1894 * 1895 * CPU1 CPU2 1896 * 1897 * sys_select receive packet 1898 * ... ... 1899 * __add_wait_queue update tp->rcv_nxt 1900 * ... ... 1901 * tp->rcv_nxt check sock_def_readable 1902 * ... { 1903 * schedule rcu_read_lock(); 1904 * wq = rcu_dereference(sk->sk_wq); 1905 * if (wq && waitqueue_active(&wq->wait)) 1906 * wake_up_interruptible(&wq->wait) 1907 * ... 1908 * } 1909 * 1910 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay 1911 * in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1 1912 * could then endup calling schedule and sleep forever if there are no more 1913 * data on the socket. 1914 * 1915 */ 1916 static inline bool wq_has_sleeper(struct socket_wq *wq) 1917 { 1918 /* We need to be sure we are in sync with the 1919 * add_wait_queue modifications to the wait queue. 1920 * 1921 * This memory barrier is paired in the sock_poll_wait. 1922 */ 1923 smp_mb(); 1924 return wq && waitqueue_active(&wq->wait); 1925 } 1926 1927 /** 1928 * sock_poll_wait - place memory barrier behind the poll_wait call. 1929 * @filp: file 1930 * @wait_address: socket wait queue 1931 * @p: poll_table 1932 * 1933 * See the comments in the wq_has_sleeper function. 1934 */ 1935 static inline void sock_poll_wait(struct file *filp, 1936 wait_queue_head_t *wait_address, poll_table *p) 1937 { 1938 if (!poll_does_not_wait(p) && wait_address) { 1939 poll_wait(filp, wait_address, p); 1940 /* We need to be sure we are in sync with the 1941 * socket flags modification. 1942 * 1943 * This memory barrier is paired in the wq_has_sleeper. 1944 */ 1945 smp_mb(); 1946 } 1947 } 1948 1949 /* 1950 * Queue a received datagram if it will fit. Stream and sequenced 1951 * protocols can't normally use this as they need to fit buffers in 1952 * and play with them. 1953 * 1954 * Inlined as it's very short and called for pretty much every 1955 * packet ever received. 1956 */ 1957 1958 static inline void skb_set_owner_w(struct sk_buff *skb, struct sock *sk) 1959 { 1960 skb_orphan(skb); 1961 skb->sk = sk; 1962 skb->destructor = sock_wfree; 1963 /* 1964 * We used to take a refcount on sk, but following operation 1965 * is enough to guarantee sk_free() wont free this sock until 1966 * all in-flight packets are completed 1967 */ 1968 atomic_add(skb->truesize, &sk->sk_wmem_alloc); 1969 } 1970 1971 static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk) 1972 { 1973 skb_orphan(skb); 1974 skb->sk = sk; 1975 skb->destructor = sock_rfree; 1976 atomic_add(skb->truesize, &sk->sk_rmem_alloc); 1977 sk_mem_charge(sk, skb->truesize); 1978 } 1979 1980 extern void sk_reset_timer(struct sock *sk, struct timer_list *timer, 1981 unsigned long expires); 1982 1983 extern void sk_stop_timer(struct sock *sk, struct timer_list *timer); 1984 1985 extern int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb); 1986 1987 extern int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb); 1988 1989 /* 1990 * Recover an error report and clear atomically 1991 */ 1992 1993 static inline int sock_error(struct sock *sk) 1994 { 1995 int err; 1996 if (likely(!sk->sk_err)) 1997 return 0; 1998 err = xchg(&sk->sk_err, 0); 1999 return -err; 2000 } 2001 2002 static inline unsigned long sock_wspace(struct sock *sk) 2003 { 2004 int amt = 0; 2005 2006 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) { 2007 amt = sk->sk_sndbuf - atomic_read(&sk->sk_wmem_alloc); 2008 if (amt < 0) 2009 amt = 0; 2010 } 2011 return amt; 2012 } 2013 2014 static inline void sk_wake_async(struct sock *sk, int how, int band) 2015 { 2016 if (sock_flag(sk, SOCK_FASYNC)) 2017 sock_wake_async(sk->sk_socket, how, band); 2018 } 2019 2020 #define SOCK_MIN_SNDBUF 2048 2021 /* 2022 * Since sk_rmem_alloc sums skb->truesize, even a small frame might need 2023 * sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak 2024 */ 2025 #define SOCK_MIN_RCVBUF (2048 + sizeof(struct sk_buff)) 2026 2027 static inline void sk_stream_moderate_sndbuf(struct sock *sk) 2028 { 2029 if (!(sk->sk_userlocks & SOCK_SNDBUF_LOCK)) { 2030 sk->sk_sndbuf = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1); 2031 sk->sk_sndbuf = max(sk->sk_sndbuf, SOCK_MIN_SNDBUF); 2032 } 2033 } 2034 2035 struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp); 2036 2037 static inline struct page *sk_stream_alloc_page(struct sock *sk) 2038 { 2039 struct page *page = NULL; 2040 2041 page = alloc_pages(sk->sk_allocation, 0); 2042 if (!page) { 2043 sk_enter_memory_pressure(sk); 2044 sk_stream_moderate_sndbuf(sk); 2045 } 2046 return page; 2047 } 2048 2049 /* 2050 * Default write policy as shown to user space via poll/select/SIGIO 2051 */ 2052 static inline bool sock_writeable(const struct sock *sk) 2053 { 2054 return atomic_read(&sk->sk_wmem_alloc) < (sk->sk_sndbuf >> 1); 2055 } 2056 2057 static inline gfp_t gfp_any(void) 2058 { 2059 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL; 2060 } 2061 2062 static inline long sock_rcvtimeo(const struct sock *sk, bool noblock) 2063 { 2064 return noblock ? 0 : sk->sk_rcvtimeo; 2065 } 2066 2067 static inline long sock_sndtimeo(const struct sock *sk, bool noblock) 2068 { 2069 return noblock ? 0 : sk->sk_sndtimeo; 2070 } 2071 2072 static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len) 2073 { 2074 return (waitall ? len : min_t(int, sk->sk_rcvlowat, len)) ? : 1; 2075 } 2076 2077 /* Alas, with timeout socket operations are not restartable. 2078 * Compare this to poll(). 2079 */ 2080 static inline int sock_intr_errno(long timeo) 2081 { 2082 return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR; 2083 } 2084 2085 extern void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk, 2086 struct sk_buff *skb); 2087 extern void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk, 2088 struct sk_buff *skb); 2089 2090 static inline void 2091 sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb) 2092 { 2093 ktime_t kt = skb->tstamp; 2094 struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb); 2095 2096 /* 2097 * generate control messages if 2098 * - receive time stamping in software requested (SOCK_RCVTSTAMP 2099 * or SOCK_TIMESTAMPING_RX_SOFTWARE) 2100 * - software time stamp available and wanted 2101 * (SOCK_TIMESTAMPING_SOFTWARE) 2102 * - hardware time stamps available and wanted 2103 * (SOCK_TIMESTAMPING_SYS_HARDWARE or 2104 * SOCK_TIMESTAMPING_RAW_HARDWARE) 2105 */ 2106 if (sock_flag(sk, SOCK_RCVTSTAMP) || 2107 sock_flag(sk, SOCK_TIMESTAMPING_RX_SOFTWARE) || 2108 (kt.tv64 && sock_flag(sk, SOCK_TIMESTAMPING_SOFTWARE)) || 2109 (hwtstamps->hwtstamp.tv64 && 2110 sock_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE)) || 2111 (hwtstamps->syststamp.tv64 && 2112 sock_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE))) 2113 __sock_recv_timestamp(msg, sk, skb); 2114 else 2115 sk->sk_stamp = kt; 2116 2117 if (sock_flag(sk, SOCK_WIFI_STATUS) && skb->wifi_acked_valid) 2118 __sock_recv_wifi_status(msg, sk, skb); 2119 } 2120 2121 extern void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk, 2122 struct sk_buff *skb); 2123 2124 static inline void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk, 2125 struct sk_buff *skb) 2126 { 2127 #define FLAGS_TS_OR_DROPS ((1UL << SOCK_RXQ_OVFL) | \ 2128 (1UL << SOCK_RCVTSTAMP) | \ 2129 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE) | \ 2130 (1UL << SOCK_TIMESTAMPING_SOFTWARE) | \ 2131 (1UL << SOCK_TIMESTAMPING_RAW_HARDWARE) | \ 2132 (1UL << SOCK_TIMESTAMPING_SYS_HARDWARE)) 2133 2134 if (sk->sk_flags & FLAGS_TS_OR_DROPS) 2135 __sock_recv_ts_and_drops(msg, sk, skb); 2136 else 2137 sk->sk_stamp = skb->tstamp; 2138 } 2139 2140 /** 2141 * sock_tx_timestamp - checks whether the outgoing packet is to be time stamped 2142 * @sk: socket sending this packet 2143 * @tx_flags: filled with instructions for time stamping 2144 * 2145 * Currently only depends on SOCK_TIMESTAMPING* flags. Returns error code if 2146 * parameters are invalid. 2147 */ 2148 extern int sock_tx_timestamp(struct sock *sk, __u8 *tx_flags); 2149 2150 /** 2151 * sk_eat_skb - Release a skb if it is no longer needed 2152 * @sk: socket to eat this skb from 2153 * @skb: socket buffer to eat 2154 * @copied_early: flag indicating whether DMA operations copied this data early 2155 * 2156 * This routine must be called with interrupts disabled or with the socket 2157 * locked so that the sk_buff queue operation is ok. 2158 */ 2159 #ifdef CONFIG_NET_DMA 2160 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb, bool copied_early) 2161 { 2162 __skb_unlink(skb, &sk->sk_receive_queue); 2163 if (!copied_early) 2164 __kfree_skb(skb); 2165 else 2166 __skb_queue_tail(&sk->sk_async_wait_queue, skb); 2167 } 2168 #else 2169 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb, bool copied_early) 2170 { 2171 __skb_unlink(skb, &sk->sk_receive_queue); 2172 __kfree_skb(skb); 2173 } 2174 #endif 2175 2176 static inline 2177 struct net *sock_net(const struct sock *sk) 2178 { 2179 return read_pnet(&sk->sk_net); 2180 } 2181 2182 static inline 2183 void sock_net_set(struct sock *sk, struct net *net) 2184 { 2185 write_pnet(&sk->sk_net, net); 2186 } 2187 2188 /* 2189 * Kernel sockets, f.e. rtnl or icmp_socket, are a part of a namespace. 2190 * They should not hold a reference to a namespace in order to allow 2191 * to stop it. 2192 * Sockets after sk_change_net should be released using sk_release_kernel 2193 */ 2194 static inline void sk_change_net(struct sock *sk, struct net *net) 2195 { 2196 put_net(sock_net(sk)); 2197 sock_net_set(sk, hold_net(net)); 2198 } 2199 2200 static inline struct sock *skb_steal_sock(struct sk_buff *skb) 2201 { 2202 if (skb->sk) { 2203 struct sock *sk = skb->sk; 2204 2205 skb->destructor = NULL; 2206 skb->sk = NULL; 2207 return sk; 2208 } 2209 return NULL; 2210 } 2211 2212 extern void sock_enable_timestamp(struct sock *sk, int flag); 2213 extern int sock_get_timestamp(struct sock *, struct timeval __user *); 2214 extern int sock_get_timestampns(struct sock *, struct timespec __user *); 2215 2216 /* 2217 * Enable debug/info messages 2218 */ 2219 extern int net_msg_warn; 2220 #define NETDEBUG(fmt, args...) \ 2221 do { if (net_msg_warn) printk(fmt,##args); } while (0) 2222 2223 #define LIMIT_NETDEBUG(fmt, args...) \ 2224 do { if (net_msg_warn && net_ratelimit()) printk(fmt,##args); } while(0) 2225 2226 extern __u32 sysctl_wmem_max; 2227 extern __u32 sysctl_rmem_max; 2228 2229 extern void sk_init(void); 2230 2231 extern int sysctl_optmem_max; 2232 2233 extern __u32 sysctl_wmem_default; 2234 extern __u32 sysctl_rmem_default; 2235 2236 #endif /* _SOCK_H */ 2237