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