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