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_TIMESTAMPING_TX_HARDWARE, /* %SOF_TIMESTAMPING_TX_HARDWARE */ 625 SOCK_TIMESTAMPING_TX_SOFTWARE, /* %SOF_TIMESTAMPING_TX_SOFTWARE */ 626 SOCK_TIMESTAMPING_RX_HARDWARE, /* %SOF_TIMESTAMPING_RX_HARDWARE */ 627 SOCK_TIMESTAMPING_RX_SOFTWARE, /* %SOF_TIMESTAMPING_RX_SOFTWARE */ 628 SOCK_TIMESTAMPING_SOFTWARE, /* %SOF_TIMESTAMPING_SOFTWARE */ 629 SOCK_TIMESTAMPING_RAW_HARDWARE, /* %SOF_TIMESTAMPING_RAW_HARDWARE */ 630 SOCK_TIMESTAMPING_SYS_HARDWARE, /* %SOF_TIMESTAMPING_SYS_HARDWARE */ 631 SOCK_FASYNC, /* fasync() active */ 632 SOCK_RXQ_OVFL, 633 SOCK_ZEROCOPY, /* buffers from userspace */ 634 SOCK_WIFI_STATUS, /* push wifi status to userspace */ 635 SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS. 636 * Will use last 4 bytes of packet sent from 637 * user-space instead. 638 */ 639 }; 640 641 static inline void sock_copy_flags(struct sock *nsk, struct sock *osk) 642 { 643 nsk->sk_flags = osk->sk_flags; 644 } 645 646 static inline void sock_set_flag(struct sock *sk, enum sock_flags flag) 647 { 648 __set_bit(flag, &sk->sk_flags); 649 } 650 651 static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag) 652 { 653 __clear_bit(flag, &sk->sk_flags); 654 } 655 656 static inline bool sock_flag(const struct sock *sk, enum sock_flags flag) 657 { 658 return test_bit(flag, &sk->sk_flags); 659 } 660 661 static inline void sk_acceptq_removed(struct sock *sk) 662 { 663 sk->sk_ack_backlog--; 664 } 665 666 static inline void sk_acceptq_added(struct sock *sk) 667 { 668 sk->sk_ack_backlog++; 669 } 670 671 static inline bool sk_acceptq_is_full(const struct sock *sk) 672 { 673 return sk->sk_ack_backlog > sk->sk_max_ack_backlog; 674 } 675 676 /* 677 * Compute minimal free write space needed to queue new packets. 678 */ 679 static inline int sk_stream_min_wspace(const struct sock *sk) 680 { 681 return sk->sk_wmem_queued >> 1; 682 } 683 684 static inline int sk_stream_wspace(const struct sock *sk) 685 { 686 return sk->sk_sndbuf - sk->sk_wmem_queued; 687 } 688 689 extern void sk_stream_write_space(struct sock *sk); 690 691 static inline bool sk_stream_memory_free(const struct sock *sk) 692 { 693 return sk->sk_wmem_queued < sk->sk_sndbuf; 694 } 695 696 /* OOB backlog add */ 697 static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb) 698 { 699 /* dont let skb dst not refcounted, we are going to leave rcu lock */ 700 skb_dst_force(skb); 701 702 if (!sk->sk_backlog.tail) 703 sk->sk_backlog.head = skb; 704 else 705 sk->sk_backlog.tail->next = skb; 706 707 sk->sk_backlog.tail = skb; 708 skb->next = NULL; 709 } 710 711 /* 712 * Take into account size of receive queue and backlog queue 713 * Do not take into account this skb truesize, 714 * to allow even a single big packet to come. 715 */ 716 static inline bool sk_rcvqueues_full(const struct sock *sk, const struct sk_buff *skb, 717 unsigned int limit) 718 { 719 unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc); 720 721 return qsize > limit; 722 } 723 724 /* The per-socket spinlock must be held here. */ 725 static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb, 726 unsigned int limit) 727 { 728 if (sk_rcvqueues_full(sk, skb, limit)) 729 return -ENOBUFS; 730 731 __sk_add_backlog(sk, skb); 732 sk->sk_backlog.len += skb->truesize; 733 return 0; 734 } 735 736 static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb) 737 { 738 return sk->sk_backlog_rcv(sk, skb); 739 } 740 741 static inline void sock_rps_record_flow(const struct sock *sk) 742 { 743 #ifdef CONFIG_RPS 744 struct rps_sock_flow_table *sock_flow_table; 745 746 rcu_read_lock(); 747 sock_flow_table = rcu_dereference(rps_sock_flow_table); 748 rps_record_sock_flow(sock_flow_table, sk->sk_rxhash); 749 rcu_read_unlock(); 750 #endif 751 } 752 753 static inline void sock_rps_reset_flow(const struct sock *sk) 754 { 755 #ifdef CONFIG_RPS 756 struct rps_sock_flow_table *sock_flow_table; 757 758 rcu_read_lock(); 759 sock_flow_table = rcu_dereference(rps_sock_flow_table); 760 rps_reset_sock_flow(sock_flow_table, sk->sk_rxhash); 761 rcu_read_unlock(); 762 #endif 763 } 764 765 static inline void sock_rps_save_rxhash(struct sock *sk, 766 const struct sk_buff *skb) 767 { 768 #ifdef CONFIG_RPS 769 if (unlikely(sk->sk_rxhash != skb->rxhash)) { 770 sock_rps_reset_flow(sk); 771 sk->sk_rxhash = skb->rxhash; 772 } 773 #endif 774 } 775 776 static inline void sock_rps_reset_rxhash(struct sock *sk) 777 { 778 #ifdef CONFIG_RPS 779 sock_rps_reset_flow(sk); 780 sk->sk_rxhash = 0; 781 #endif 782 } 783 784 #define sk_wait_event(__sk, __timeo, __condition) \ 785 ({ int __rc; \ 786 release_sock(__sk); \ 787 __rc = __condition; \ 788 if (!__rc) { \ 789 *(__timeo) = schedule_timeout(*(__timeo)); \ 790 } \ 791 lock_sock(__sk); \ 792 __rc = __condition; \ 793 __rc; \ 794 }) 795 796 extern int sk_stream_wait_connect(struct sock *sk, long *timeo_p); 797 extern int sk_stream_wait_memory(struct sock *sk, long *timeo_p); 798 extern void sk_stream_wait_close(struct sock *sk, long timeo_p); 799 extern int sk_stream_error(struct sock *sk, int flags, int err); 800 extern void sk_stream_kill_queues(struct sock *sk); 801 802 extern int sk_wait_data(struct sock *sk, long *timeo); 803 804 struct request_sock_ops; 805 struct timewait_sock_ops; 806 struct inet_hashinfo; 807 struct raw_hashinfo; 808 struct module; 809 810 /* Networking protocol blocks we attach to sockets. 811 * socket layer -> transport layer interface 812 * transport -> network interface is defined by struct inet_proto 813 */ 814 struct proto { 815 void (*close)(struct sock *sk, 816 long timeout); 817 int (*connect)(struct sock *sk, 818 struct sockaddr *uaddr, 819 int addr_len); 820 int (*disconnect)(struct sock *sk, int flags); 821 822 struct sock * (*accept)(struct sock *sk, int flags, int *err); 823 824 int (*ioctl)(struct sock *sk, int cmd, 825 unsigned long arg); 826 int (*init)(struct sock *sk); 827 void (*destroy)(struct sock *sk); 828 void (*shutdown)(struct sock *sk, int how); 829 int (*setsockopt)(struct sock *sk, int level, 830 int optname, char __user *optval, 831 unsigned int optlen); 832 int (*getsockopt)(struct sock *sk, int level, 833 int optname, char __user *optval, 834 int __user *option); 835 #ifdef CONFIG_COMPAT 836 int (*compat_setsockopt)(struct sock *sk, 837 int level, 838 int optname, char __user *optval, 839 unsigned int optlen); 840 int (*compat_getsockopt)(struct sock *sk, 841 int level, 842 int optname, char __user *optval, 843 int __user *option); 844 int (*compat_ioctl)(struct sock *sk, 845 unsigned int cmd, unsigned long arg); 846 #endif 847 int (*sendmsg)(struct kiocb *iocb, struct sock *sk, 848 struct msghdr *msg, size_t len); 849 int (*recvmsg)(struct kiocb *iocb, struct sock *sk, 850 struct msghdr *msg, 851 size_t len, int noblock, int flags, 852 int *addr_len); 853 int (*sendpage)(struct sock *sk, struct page *page, 854 int offset, size_t size, int flags); 855 int (*bind)(struct sock *sk, 856 struct sockaddr *uaddr, int addr_len); 857 858 int (*backlog_rcv) (struct sock *sk, 859 struct sk_buff *skb); 860 861 void (*release_cb)(struct sock *sk); 862 void (*mtu_reduced)(struct sock *sk); 863 864 /* Keeping track of sk's, looking them up, and port selection methods. */ 865 void (*hash)(struct sock *sk); 866 void (*unhash)(struct sock *sk); 867 void (*rehash)(struct sock *sk); 868 int (*get_port)(struct sock *sk, unsigned short snum); 869 void (*clear_sk)(struct sock *sk, int size); 870 871 /* Keeping track of sockets in use */ 872 #ifdef CONFIG_PROC_FS 873 unsigned int inuse_idx; 874 #endif 875 876 /* Memory pressure */ 877 void (*enter_memory_pressure)(struct sock *sk); 878 atomic_long_t *memory_allocated; /* Current allocated memory. */ 879 struct percpu_counter *sockets_allocated; /* Current number of sockets. */ 880 /* 881 * Pressure flag: try to collapse. 882 * Technical note: it is used by multiple contexts non atomically. 883 * All the __sk_mem_schedule() is of this nature: accounting 884 * is strict, actions are advisory and have some latency. 885 */ 886 int *memory_pressure; 887 long *sysctl_mem; 888 int *sysctl_wmem; 889 int *sysctl_rmem; 890 int max_header; 891 bool no_autobind; 892 893 struct kmem_cache *slab; 894 unsigned int obj_size; 895 int slab_flags; 896 897 struct percpu_counter *orphan_count; 898 899 struct request_sock_ops *rsk_prot; 900 struct timewait_sock_ops *twsk_prot; 901 902 union { 903 struct inet_hashinfo *hashinfo; 904 struct udp_table *udp_table; 905 struct raw_hashinfo *raw_hash; 906 } h; 907 908 struct module *owner; 909 910 char name[32]; 911 912 struct list_head node; 913 #ifdef SOCK_REFCNT_DEBUG 914 atomic_t socks; 915 #endif 916 #ifdef CONFIG_CGROUP_MEM_RES_CTLR_KMEM 917 /* 918 * cgroup specific init/deinit functions. Called once for all 919 * protocols that implement it, from cgroups populate function. 920 * This function has to setup any files the protocol want to 921 * appear in the kmem cgroup filesystem. 922 */ 923 int (*init_cgroup)(struct mem_cgroup *memcg, 924 struct cgroup_subsys *ss); 925 void (*destroy_cgroup)(struct mem_cgroup *memcg); 926 struct cg_proto *(*proto_cgroup)(struct mem_cgroup *memcg); 927 #endif 928 }; 929 930 /* 931 * Bits in struct cg_proto.flags 932 */ 933 enum cg_proto_flags { 934 /* Currently active and new sockets should be assigned to cgroups */ 935 MEMCG_SOCK_ACTIVE, 936 /* It was ever activated; we must disarm static keys on destruction */ 937 MEMCG_SOCK_ACTIVATED, 938 }; 939 940 struct cg_proto { 941 void (*enter_memory_pressure)(struct sock *sk); 942 struct res_counter *memory_allocated; /* Current allocated memory. */ 943 struct percpu_counter *sockets_allocated; /* Current number of sockets. */ 944 int *memory_pressure; 945 long *sysctl_mem; 946 unsigned long flags; 947 /* 948 * memcg field is used to find which memcg we belong directly 949 * Each memcg struct can hold more than one cg_proto, so container_of 950 * won't really cut. 951 * 952 * The elegant solution would be having an inverse function to 953 * proto_cgroup in struct proto, but that means polluting the structure 954 * for everybody, instead of just for memcg users. 955 */ 956 struct mem_cgroup *memcg; 957 }; 958 959 extern int proto_register(struct proto *prot, int alloc_slab); 960 extern void proto_unregister(struct proto *prot); 961 962 static inline bool memcg_proto_active(struct cg_proto *cg_proto) 963 { 964 return test_bit(MEMCG_SOCK_ACTIVE, &cg_proto->flags); 965 } 966 967 static inline bool memcg_proto_activated(struct cg_proto *cg_proto) 968 { 969 return test_bit(MEMCG_SOCK_ACTIVATED, &cg_proto->flags); 970 } 971 972 #ifdef SOCK_REFCNT_DEBUG 973 static inline void sk_refcnt_debug_inc(struct sock *sk) 974 { 975 atomic_inc(&sk->sk_prot->socks); 976 } 977 978 static inline void sk_refcnt_debug_dec(struct sock *sk) 979 { 980 atomic_dec(&sk->sk_prot->socks); 981 printk(KERN_DEBUG "%s socket %p released, %d are still alive\n", 982 sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks)); 983 } 984 985 inline void sk_refcnt_debug_release(const struct sock *sk) 986 { 987 if (atomic_read(&sk->sk_refcnt) != 1) 988 printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n", 989 sk->sk_prot->name, sk, atomic_read(&sk->sk_refcnt)); 990 } 991 #else /* SOCK_REFCNT_DEBUG */ 992 #define sk_refcnt_debug_inc(sk) do { } while (0) 993 #define sk_refcnt_debug_dec(sk) do { } while (0) 994 #define sk_refcnt_debug_release(sk) do { } while (0) 995 #endif /* SOCK_REFCNT_DEBUG */ 996 997 #if defined(CONFIG_CGROUP_MEM_RES_CTLR_KMEM) && defined(CONFIG_NET) 998 extern struct static_key memcg_socket_limit_enabled; 999 static inline struct cg_proto *parent_cg_proto(struct proto *proto, 1000 struct cg_proto *cg_proto) 1001 { 1002 return proto->proto_cgroup(parent_mem_cgroup(cg_proto->memcg)); 1003 } 1004 #define mem_cgroup_sockets_enabled static_key_false(&memcg_socket_limit_enabled) 1005 #else 1006 #define mem_cgroup_sockets_enabled 0 1007 static inline struct cg_proto *parent_cg_proto(struct proto *proto, 1008 struct cg_proto *cg_proto) 1009 { 1010 return NULL; 1011 } 1012 #endif 1013 1014 1015 static inline bool sk_has_memory_pressure(const struct sock *sk) 1016 { 1017 return sk->sk_prot->memory_pressure != NULL; 1018 } 1019 1020 static inline bool sk_under_memory_pressure(const struct sock *sk) 1021 { 1022 if (!sk->sk_prot->memory_pressure) 1023 return false; 1024 1025 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) 1026 return !!*sk->sk_cgrp->memory_pressure; 1027 1028 return !!*sk->sk_prot->memory_pressure; 1029 } 1030 1031 static inline void sk_leave_memory_pressure(struct sock *sk) 1032 { 1033 int *memory_pressure = sk->sk_prot->memory_pressure; 1034 1035 if (!memory_pressure) 1036 return; 1037 1038 if (*memory_pressure) 1039 *memory_pressure = 0; 1040 1041 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) { 1042 struct cg_proto *cg_proto = sk->sk_cgrp; 1043 struct proto *prot = sk->sk_prot; 1044 1045 for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto)) 1046 if (*cg_proto->memory_pressure) 1047 *cg_proto->memory_pressure = 0; 1048 } 1049 1050 } 1051 1052 static inline void sk_enter_memory_pressure(struct sock *sk) 1053 { 1054 if (!sk->sk_prot->enter_memory_pressure) 1055 return; 1056 1057 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) { 1058 struct cg_proto *cg_proto = sk->sk_cgrp; 1059 struct proto *prot = sk->sk_prot; 1060 1061 for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto)) 1062 cg_proto->enter_memory_pressure(sk); 1063 } 1064 1065 sk->sk_prot->enter_memory_pressure(sk); 1066 } 1067 1068 static inline long sk_prot_mem_limits(const struct sock *sk, int index) 1069 { 1070 long *prot = sk->sk_prot->sysctl_mem; 1071 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) 1072 prot = sk->sk_cgrp->sysctl_mem; 1073 return prot[index]; 1074 } 1075 1076 static inline void memcg_memory_allocated_add(struct cg_proto *prot, 1077 unsigned long amt, 1078 int *parent_status) 1079 { 1080 struct res_counter *fail; 1081 int ret; 1082 1083 ret = res_counter_charge_nofail(prot->memory_allocated, 1084 amt << PAGE_SHIFT, &fail); 1085 if (ret < 0) 1086 *parent_status = OVER_LIMIT; 1087 } 1088 1089 static inline void memcg_memory_allocated_sub(struct cg_proto *prot, 1090 unsigned long amt) 1091 { 1092 res_counter_uncharge(prot->memory_allocated, amt << PAGE_SHIFT); 1093 } 1094 1095 static inline u64 memcg_memory_allocated_read(struct cg_proto *prot) 1096 { 1097 u64 ret; 1098 ret = res_counter_read_u64(prot->memory_allocated, RES_USAGE); 1099 return ret >> PAGE_SHIFT; 1100 } 1101 1102 static inline long 1103 sk_memory_allocated(const struct sock *sk) 1104 { 1105 struct proto *prot = sk->sk_prot; 1106 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) 1107 return memcg_memory_allocated_read(sk->sk_cgrp); 1108 1109 return atomic_long_read(prot->memory_allocated); 1110 } 1111 1112 static inline long 1113 sk_memory_allocated_add(struct sock *sk, int amt, int *parent_status) 1114 { 1115 struct proto *prot = sk->sk_prot; 1116 1117 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) { 1118 memcg_memory_allocated_add(sk->sk_cgrp, amt, parent_status); 1119 /* update the root cgroup regardless */ 1120 atomic_long_add_return(amt, prot->memory_allocated); 1121 return memcg_memory_allocated_read(sk->sk_cgrp); 1122 } 1123 1124 return atomic_long_add_return(amt, prot->memory_allocated); 1125 } 1126 1127 static inline void 1128 sk_memory_allocated_sub(struct sock *sk, int amt) 1129 { 1130 struct proto *prot = sk->sk_prot; 1131 1132 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) 1133 memcg_memory_allocated_sub(sk->sk_cgrp, amt); 1134 1135 atomic_long_sub(amt, prot->memory_allocated); 1136 } 1137 1138 static inline void sk_sockets_allocated_dec(struct sock *sk) 1139 { 1140 struct proto *prot = sk->sk_prot; 1141 1142 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) { 1143 struct cg_proto *cg_proto = sk->sk_cgrp; 1144 1145 for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto)) 1146 percpu_counter_dec(cg_proto->sockets_allocated); 1147 } 1148 1149 percpu_counter_dec(prot->sockets_allocated); 1150 } 1151 1152 static inline void sk_sockets_allocated_inc(struct sock *sk) 1153 { 1154 struct proto *prot = sk->sk_prot; 1155 1156 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) { 1157 struct cg_proto *cg_proto = sk->sk_cgrp; 1158 1159 for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto)) 1160 percpu_counter_inc(cg_proto->sockets_allocated); 1161 } 1162 1163 percpu_counter_inc(prot->sockets_allocated); 1164 } 1165 1166 static inline int 1167 sk_sockets_allocated_read_positive(struct sock *sk) 1168 { 1169 struct proto *prot = sk->sk_prot; 1170 1171 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) 1172 return percpu_counter_read_positive(sk->sk_cgrp->sockets_allocated); 1173 1174 return percpu_counter_read_positive(prot->sockets_allocated); 1175 } 1176 1177 static inline int 1178 proto_sockets_allocated_sum_positive(struct proto *prot) 1179 { 1180 return percpu_counter_sum_positive(prot->sockets_allocated); 1181 } 1182 1183 static inline long 1184 proto_memory_allocated(struct proto *prot) 1185 { 1186 return atomic_long_read(prot->memory_allocated); 1187 } 1188 1189 static inline bool 1190 proto_memory_pressure(struct proto *prot) 1191 { 1192 if (!prot->memory_pressure) 1193 return false; 1194 return !!*prot->memory_pressure; 1195 } 1196 1197 1198 #ifdef CONFIG_PROC_FS 1199 /* Called with local bh disabled */ 1200 extern void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc); 1201 extern int sock_prot_inuse_get(struct net *net, struct proto *proto); 1202 #else 1203 static inline void sock_prot_inuse_add(struct net *net, struct proto *prot, 1204 int inc) 1205 { 1206 } 1207 #endif 1208 1209 1210 /* With per-bucket locks this operation is not-atomic, so that 1211 * this version is not worse. 1212 */ 1213 static inline void __sk_prot_rehash(struct sock *sk) 1214 { 1215 sk->sk_prot->unhash(sk); 1216 sk->sk_prot->hash(sk); 1217 } 1218 1219 void sk_prot_clear_portaddr_nulls(struct sock *sk, int size); 1220 1221 /* About 10 seconds */ 1222 #define SOCK_DESTROY_TIME (10*HZ) 1223 1224 /* Sockets 0-1023 can't be bound to unless you are superuser */ 1225 #define PROT_SOCK 1024 1226 1227 #define SHUTDOWN_MASK 3 1228 #define RCV_SHUTDOWN 1 1229 #define SEND_SHUTDOWN 2 1230 1231 #define SOCK_SNDBUF_LOCK 1 1232 #define SOCK_RCVBUF_LOCK 2 1233 #define SOCK_BINDADDR_LOCK 4 1234 #define SOCK_BINDPORT_LOCK 8 1235 1236 /* sock_iocb: used to kick off async processing of socket ios */ 1237 struct sock_iocb { 1238 struct list_head list; 1239 1240 int flags; 1241 int size; 1242 struct socket *sock; 1243 struct sock *sk; 1244 struct scm_cookie *scm; 1245 struct msghdr *msg, async_msg; 1246 struct kiocb *kiocb; 1247 }; 1248 1249 static inline struct sock_iocb *kiocb_to_siocb(struct kiocb *iocb) 1250 { 1251 return (struct sock_iocb *)iocb->private; 1252 } 1253 1254 static inline struct kiocb *siocb_to_kiocb(struct sock_iocb *si) 1255 { 1256 return si->kiocb; 1257 } 1258 1259 struct socket_alloc { 1260 struct socket socket; 1261 struct inode vfs_inode; 1262 }; 1263 1264 static inline struct socket *SOCKET_I(struct inode *inode) 1265 { 1266 return &container_of(inode, struct socket_alloc, vfs_inode)->socket; 1267 } 1268 1269 static inline struct inode *SOCK_INODE(struct socket *socket) 1270 { 1271 return &container_of(socket, struct socket_alloc, socket)->vfs_inode; 1272 } 1273 1274 /* 1275 * Functions for memory accounting 1276 */ 1277 extern int __sk_mem_schedule(struct sock *sk, int size, int kind); 1278 extern void __sk_mem_reclaim(struct sock *sk); 1279 1280 #define SK_MEM_QUANTUM ((int)PAGE_SIZE) 1281 #define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM) 1282 #define SK_MEM_SEND 0 1283 #define SK_MEM_RECV 1 1284 1285 static inline int sk_mem_pages(int amt) 1286 { 1287 return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT; 1288 } 1289 1290 static inline bool sk_has_account(struct sock *sk) 1291 { 1292 /* return true if protocol supports memory accounting */ 1293 return !!sk->sk_prot->memory_allocated; 1294 } 1295 1296 static inline bool sk_wmem_schedule(struct sock *sk, int size) 1297 { 1298 if (!sk_has_account(sk)) 1299 return true; 1300 return size <= sk->sk_forward_alloc || 1301 __sk_mem_schedule(sk, size, SK_MEM_SEND); 1302 } 1303 1304 static inline bool sk_rmem_schedule(struct sock *sk, int size) 1305 { 1306 if (!sk_has_account(sk)) 1307 return true; 1308 return size <= sk->sk_forward_alloc || 1309 __sk_mem_schedule(sk, size, SK_MEM_RECV); 1310 } 1311 1312 static inline void sk_mem_reclaim(struct sock *sk) 1313 { 1314 if (!sk_has_account(sk)) 1315 return; 1316 if (sk->sk_forward_alloc >= SK_MEM_QUANTUM) 1317 __sk_mem_reclaim(sk); 1318 } 1319 1320 static inline void sk_mem_reclaim_partial(struct sock *sk) 1321 { 1322 if (!sk_has_account(sk)) 1323 return; 1324 if (sk->sk_forward_alloc > SK_MEM_QUANTUM) 1325 __sk_mem_reclaim(sk); 1326 } 1327 1328 static inline void sk_mem_charge(struct sock *sk, int size) 1329 { 1330 if (!sk_has_account(sk)) 1331 return; 1332 sk->sk_forward_alloc -= size; 1333 } 1334 1335 static inline void sk_mem_uncharge(struct sock *sk, int size) 1336 { 1337 if (!sk_has_account(sk)) 1338 return; 1339 sk->sk_forward_alloc += size; 1340 } 1341 1342 static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb) 1343 { 1344 sock_set_flag(sk, SOCK_QUEUE_SHRUNK); 1345 sk->sk_wmem_queued -= skb->truesize; 1346 sk_mem_uncharge(sk, skb->truesize); 1347 __kfree_skb(skb); 1348 } 1349 1350 /* Used by processes to "lock" a socket state, so that 1351 * interrupts and bottom half handlers won't change it 1352 * from under us. It essentially blocks any incoming 1353 * packets, so that we won't get any new data or any 1354 * packets that change the state of the socket. 1355 * 1356 * While locked, BH processing will add new packets to 1357 * the backlog queue. This queue is processed by the 1358 * owner of the socket lock right before it is released. 1359 * 1360 * Since ~2.3.5 it is also exclusive sleep lock serializing 1361 * accesses from user process context. 1362 */ 1363 #define sock_owned_by_user(sk) ((sk)->sk_lock.owned) 1364 1365 /* 1366 * Macro so as to not evaluate some arguments when 1367 * lockdep is not enabled. 1368 * 1369 * Mark both the sk_lock and the sk_lock.slock as a 1370 * per-address-family lock class. 1371 */ 1372 #define sock_lock_init_class_and_name(sk, sname, skey, name, key) \ 1373 do { \ 1374 sk->sk_lock.owned = 0; \ 1375 init_waitqueue_head(&sk->sk_lock.wq); \ 1376 spin_lock_init(&(sk)->sk_lock.slock); \ 1377 debug_check_no_locks_freed((void *)&(sk)->sk_lock, \ 1378 sizeof((sk)->sk_lock)); \ 1379 lockdep_set_class_and_name(&(sk)->sk_lock.slock, \ 1380 (skey), (sname)); \ 1381 lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \ 1382 } while (0) 1383 1384 extern void lock_sock_nested(struct sock *sk, int subclass); 1385 1386 static inline void lock_sock(struct sock *sk) 1387 { 1388 lock_sock_nested(sk, 0); 1389 } 1390 1391 extern void release_sock(struct sock *sk); 1392 1393 /* BH context may only use the following locking interface. */ 1394 #define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock)) 1395 #define bh_lock_sock_nested(__sk) \ 1396 spin_lock_nested(&((__sk)->sk_lock.slock), \ 1397 SINGLE_DEPTH_NESTING) 1398 #define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock)) 1399 1400 extern bool lock_sock_fast(struct sock *sk); 1401 /** 1402 * unlock_sock_fast - complement of lock_sock_fast 1403 * @sk: socket 1404 * @slow: slow mode 1405 * 1406 * fast unlock socket for user context. 1407 * If slow mode is on, we call regular release_sock() 1408 */ 1409 static inline void unlock_sock_fast(struct sock *sk, bool slow) 1410 { 1411 if (slow) 1412 release_sock(sk); 1413 else 1414 spin_unlock_bh(&sk->sk_lock.slock); 1415 } 1416 1417 1418 extern struct sock *sk_alloc(struct net *net, int family, 1419 gfp_t priority, 1420 struct proto *prot); 1421 extern void sk_free(struct sock *sk); 1422 extern void sk_release_kernel(struct sock *sk); 1423 extern struct sock *sk_clone_lock(const struct sock *sk, 1424 const gfp_t priority); 1425 1426 extern struct sk_buff *sock_wmalloc(struct sock *sk, 1427 unsigned long size, int force, 1428 gfp_t priority); 1429 extern struct sk_buff *sock_rmalloc(struct sock *sk, 1430 unsigned long size, int force, 1431 gfp_t priority); 1432 extern void sock_wfree(struct sk_buff *skb); 1433 extern void sock_rfree(struct sk_buff *skb); 1434 extern void sock_edemux(struct sk_buff *skb); 1435 1436 extern int sock_setsockopt(struct socket *sock, int level, 1437 int op, char __user *optval, 1438 unsigned int optlen); 1439 1440 extern int sock_getsockopt(struct socket *sock, int level, 1441 int op, char __user *optval, 1442 int __user *optlen); 1443 extern struct sk_buff *sock_alloc_send_skb(struct sock *sk, 1444 unsigned long size, 1445 int noblock, 1446 int *errcode); 1447 extern struct sk_buff *sock_alloc_send_pskb(struct sock *sk, 1448 unsigned long header_len, 1449 unsigned long data_len, 1450 int noblock, 1451 int *errcode); 1452 extern void *sock_kmalloc(struct sock *sk, int size, 1453 gfp_t priority); 1454 extern void sock_kfree_s(struct sock *sk, void *mem, int size); 1455 extern void sk_send_sigurg(struct sock *sk); 1456 1457 #ifdef CONFIG_CGROUPS 1458 extern void sock_update_classid(struct sock *sk); 1459 #else 1460 static inline void sock_update_classid(struct sock *sk) 1461 { 1462 } 1463 #endif 1464 1465 /* 1466 * Functions to fill in entries in struct proto_ops when a protocol 1467 * does not implement a particular function. 1468 */ 1469 extern int sock_no_bind(struct socket *, 1470 struct sockaddr *, int); 1471 extern int sock_no_connect(struct socket *, 1472 struct sockaddr *, int, int); 1473 extern int sock_no_socketpair(struct socket *, 1474 struct socket *); 1475 extern int sock_no_accept(struct socket *, 1476 struct socket *, int); 1477 extern int sock_no_getname(struct socket *, 1478 struct sockaddr *, int *, int); 1479 extern unsigned int sock_no_poll(struct file *, struct socket *, 1480 struct poll_table_struct *); 1481 extern int sock_no_ioctl(struct socket *, unsigned int, 1482 unsigned long); 1483 extern int sock_no_listen(struct socket *, int); 1484 extern int sock_no_shutdown(struct socket *, int); 1485 extern int sock_no_getsockopt(struct socket *, int , int, 1486 char __user *, int __user *); 1487 extern int sock_no_setsockopt(struct socket *, int, int, 1488 char __user *, unsigned int); 1489 extern int sock_no_sendmsg(struct kiocb *, struct socket *, 1490 struct msghdr *, size_t); 1491 extern int sock_no_recvmsg(struct kiocb *, struct socket *, 1492 struct msghdr *, size_t, int); 1493 extern int sock_no_mmap(struct file *file, 1494 struct socket *sock, 1495 struct vm_area_struct *vma); 1496 extern ssize_t sock_no_sendpage(struct socket *sock, 1497 struct page *page, 1498 int offset, size_t size, 1499 int flags); 1500 1501 /* 1502 * Functions to fill in entries in struct proto_ops when a protocol 1503 * uses the inet style. 1504 */ 1505 extern int sock_common_getsockopt(struct socket *sock, int level, int optname, 1506 char __user *optval, int __user *optlen); 1507 extern int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock, 1508 struct msghdr *msg, size_t size, int flags); 1509 extern int sock_common_setsockopt(struct socket *sock, int level, int optname, 1510 char __user *optval, unsigned int optlen); 1511 extern int compat_sock_common_getsockopt(struct socket *sock, int level, 1512 int optname, char __user *optval, int __user *optlen); 1513 extern int compat_sock_common_setsockopt(struct socket *sock, int level, 1514 int optname, char __user *optval, unsigned int optlen); 1515 1516 extern void sk_common_release(struct sock *sk); 1517 1518 /* 1519 * Default socket callbacks and setup code 1520 */ 1521 1522 /* Initialise core socket variables */ 1523 extern void sock_init_data(struct socket *sock, struct sock *sk); 1524 1525 extern void sk_filter_release_rcu(struct rcu_head *rcu); 1526 1527 /** 1528 * sk_filter_release - release a socket filter 1529 * @fp: filter to remove 1530 * 1531 * Remove a filter from a socket and release its resources. 1532 */ 1533 1534 static inline void sk_filter_release(struct sk_filter *fp) 1535 { 1536 if (atomic_dec_and_test(&fp->refcnt)) 1537 call_rcu(&fp->rcu, sk_filter_release_rcu); 1538 } 1539 1540 static inline void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp) 1541 { 1542 unsigned int size = sk_filter_len(fp); 1543 1544 atomic_sub(size, &sk->sk_omem_alloc); 1545 sk_filter_release(fp); 1546 } 1547 1548 static inline void sk_filter_charge(struct sock *sk, struct sk_filter *fp) 1549 { 1550 atomic_inc(&fp->refcnt); 1551 atomic_add(sk_filter_len(fp), &sk->sk_omem_alloc); 1552 } 1553 1554 /* 1555 * Socket reference counting postulates. 1556 * 1557 * * Each user of socket SHOULD hold a reference count. 1558 * * Each access point to socket (an hash table bucket, reference from a list, 1559 * running timer, skb in flight MUST hold a reference count. 1560 * * When reference count hits 0, it means it will never increase back. 1561 * * When reference count hits 0, it means that no references from 1562 * outside exist to this socket and current process on current CPU 1563 * is last user and may/should destroy this socket. 1564 * * sk_free is called from any context: process, BH, IRQ. When 1565 * it is called, socket has no references from outside -> sk_free 1566 * may release descendant resources allocated by the socket, but 1567 * to the time when it is called, socket is NOT referenced by any 1568 * hash tables, lists etc. 1569 * * Packets, delivered from outside (from network or from another process) 1570 * and enqueued on receive/error queues SHOULD NOT grab reference count, 1571 * when they sit in queue. Otherwise, packets will leak to hole, when 1572 * socket is looked up by one cpu and unhasing is made by another CPU. 1573 * It is true for udp/raw, netlink (leak to receive and error queues), tcp 1574 * (leak to backlog). Packet socket does all the processing inside 1575 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets 1576 * use separate SMP lock, so that they are prone too. 1577 */ 1578 1579 /* Ungrab socket and destroy it, if it was the last reference. */ 1580 static inline void sock_put(struct sock *sk) 1581 { 1582 if (atomic_dec_and_test(&sk->sk_refcnt)) 1583 sk_free(sk); 1584 } 1585 1586 extern int sk_receive_skb(struct sock *sk, struct sk_buff *skb, 1587 const int nested); 1588 1589 static inline void sk_tx_queue_set(struct sock *sk, int tx_queue) 1590 { 1591 sk->sk_tx_queue_mapping = tx_queue; 1592 } 1593 1594 static inline void sk_tx_queue_clear(struct sock *sk) 1595 { 1596 sk->sk_tx_queue_mapping = -1; 1597 } 1598 1599 static inline int sk_tx_queue_get(const struct sock *sk) 1600 { 1601 return sk ? sk->sk_tx_queue_mapping : -1; 1602 } 1603 1604 static inline void sk_set_socket(struct sock *sk, struct socket *sock) 1605 { 1606 sk_tx_queue_clear(sk); 1607 sk->sk_socket = sock; 1608 } 1609 1610 static inline wait_queue_head_t *sk_sleep(struct sock *sk) 1611 { 1612 BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0); 1613 return &rcu_dereference_raw(sk->sk_wq)->wait; 1614 } 1615 /* Detach socket from process context. 1616 * Announce socket dead, detach it from wait queue and inode. 1617 * Note that parent inode held reference count on this struct sock, 1618 * we do not release it in this function, because protocol 1619 * probably wants some additional cleanups or even continuing 1620 * to work with this socket (TCP). 1621 */ 1622 static inline void sock_orphan(struct sock *sk) 1623 { 1624 write_lock_bh(&sk->sk_callback_lock); 1625 sock_set_flag(sk, SOCK_DEAD); 1626 sk_set_socket(sk, NULL); 1627 sk->sk_wq = NULL; 1628 write_unlock_bh(&sk->sk_callback_lock); 1629 } 1630 1631 static inline void sock_graft(struct sock *sk, struct socket *parent) 1632 { 1633 write_lock_bh(&sk->sk_callback_lock); 1634 sk->sk_wq = parent->wq; 1635 parent->sk = sk; 1636 sk_set_socket(sk, parent); 1637 security_sock_graft(sk, parent); 1638 write_unlock_bh(&sk->sk_callback_lock); 1639 } 1640 1641 extern int sock_i_uid(struct sock *sk); 1642 extern unsigned long sock_i_ino(struct sock *sk); 1643 1644 static inline struct dst_entry * 1645 __sk_dst_get(struct sock *sk) 1646 { 1647 return rcu_dereference_check(sk->sk_dst_cache, sock_owned_by_user(sk) || 1648 lockdep_is_held(&sk->sk_lock.slock)); 1649 } 1650 1651 static inline struct dst_entry * 1652 sk_dst_get(struct sock *sk) 1653 { 1654 struct dst_entry *dst; 1655 1656 rcu_read_lock(); 1657 dst = rcu_dereference(sk->sk_dst_cache); 1658 if (dst) 1659 dst_hold(dst); 1660 rcu_read_unlock(); 1661 return dst; 1662 } 1663 1664 extern void sk_reset_txq(struct sock *sk); 1665 1666 static inline void dst_negative_advice(struct sock *sk) 1667 { 1668 struct dst_entry *ndst, *dst = __sk_dst_get(sk); 1669 1670 if (dst && dst->ops->negative_advice) { 1671 ndst = dst->ops->negative_advice(dst); 1672 1673 if (ndst != dst) { 1674 rcu_assign_pointer(sk->sk_dst_cache, ndst); 1675 sk_reset_txq(sk); 1676 } 1677 } 1678 } 1679 1680 static inline void 1681 __sk_dst_set(struct sock *sk, struct dst_entry *dst) 1682 { 1683 struct dst_entry *old_dst; 1684 1685 sk_tx_queue_clear(sk); 1686 /* 1687 * This can be called while sk is owned by the caller only, 1688 * with no state that can be checked in a rcu_dereference_check() cond 1689 */ 1690 old_dst = rcu_dereference_raw(sk->sk_dst_cache); 1691 rcu_assign_pointer(sk->sk_dst_cache, dst); 1692 dst_release(old_dst); 1693 } 1694 1695 static inline void 1696 sk_dst_set(struct sock *sk, struct dst_entry *dst) 1697 { 1698 spin_lock(&sk->sk_dst_lock); 1699 __sk_dst_set(sk, dst); 1700 spin_unlock(&sk->sk_dst_lock); 1701 } 1702 1703 static inline void 1704 __sk_dst_reset(struct sock *sk) 1705 { 1706 __sk_dst_set(sk, NULL); 1707 } 1708 1709 static inline void 1710 sk_dst_reset(struct sock *sk) 1711 { 1712 spin_lock(&sk->sk_dst_lock); 1713 __sk_dst_reset(sk); 1714 spin_unlock(&sk->sk_dst_lock); 1715 } 1716 1717 extern struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie); 1718 1719 extern struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie); 1720 1721 static inline bool sk_can_gso(const struct sock *sk) 1722 { 1723 return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type); 1724 } 1725 1726 extern void sk_setup_caps(struct sock *sk, struct dst_entry *dst); 1727 1728 static inline void sk_nocaps_add(struct sock *sk, netdev_features_t flags) 1729 { 1730 sk->sk_route_nocaps |= flags; 1731 sk->sk_route_caps &= ~flags; 1732 } 1733 1734 static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb, 1735 char __user *from, char *to, 1736 int copy, int offset) 1737 { 1738 if (skb->ip_summed == CHECKSUM_NONE) { 1739 int err = 0; 1740 __wsum csum = csum_and_copy_from_user(from, to, copy, 0, &err); 1741 if (err) 1742 return err; 1743 skb->csum = csum_block_add(skb->csum, csum, offset); 1744 } else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) { 1745 if (!access_ok(VERIFY_READ, from, copy) || 1746 __copy_from_user_nocache(to, from, copy)) 1747 return -EFAULT; 1748 } else if (copy_from_user(to, from, copy)) 1749 return -EFAULT; 1750 1751 return 0; 1752 } 1753 1754 static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb, 1755 char __user *from, int copy) 1756 { 1757 int err, offset = skb->len; 1758 1759 err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy), 1760 copy, offset); 1761 if (err) 1762 __skb_trim(skb, offset); 1763 1764 return err; 1765 } 1766 1767 static inline int skb_copy_to_page_nocache(struct sock *sk, char __user *from, 1768 struct sk_buff *skb, 1769 struct page *page, 1770 int off, int copy) 1771 { 1772 int err; 1773 1774 err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off, 1775 copy, skb->len); 1776 if (err) 1777 return err; 1778 1779 skb->len += copy; 1780 skb->data_len += copy; 1781 skb->truesize += copy; 1782 sk->sk_wmem_queued += copy; 1783 sk_mem_charge(sk, copy); 1784 return 0; 1785 } 1786 1787 static inline int skb_copy_to_page(struct sock *sk, char __user *from, 1788 struct sk_buff *skb, struct page *page, 1789 int off, int copy) 1790 { 1791 if (skb->ip_summed == CHECKSUM_NONE) { 1792 int err = 0; 1793 __wsum csum = csum_and_copy_from_user(from, 1794 page_address(page) + off, 1795 copy, 0, &err); 1796 if (err) 1797 return err; 1798 skb->csum = csum_block_add(skb->csum, csum, skb->len); 1799 } else if (copy_from_user(page_address(page) + off, from, copy)) 1800 return -EFAULT; 1801 1802 skb->len += copy; 1803 skb->data_len += copy; 1804 skb->truesize += copy; 1805 sk->sk_wmem_queued += copy; 1806 sk_mem_charge(sk, copy); 1807 return 0; 1808 } 1809 1810 /** 1811 * sk_wmem_alloc_get - returns write allocations 1812 * @sk: socket 1813 * 1814 * Returns sk_wmem_alloc minus initial offset of one 1815 */ 1816 static inline int sk_wmem_alloc_get(const struct sock *sk) 1817 { 1818 return atomic_read(&sk->sk_wmem_alloc) - 1; 1819 } 1820 1821 /** 1822 * sk_rmem_alloc_get - returns read allocations 1823 * @sk: socket 1824 * 1825 * Returns sk_rmem_alloc 1826 */ 1827 static inline int sk_rmem_alloc_get(const struct sock *sk) 1828 { 1829 return atomic_read(&sk->sk_rmem_alloc); 1830 } 1831 1832 /** 1833 * sk_has_allocations - check if allocations are outstanding 1834 * @sk: socket 1835 * 1836 * Returns true if socket has write or read allocations 1837 */ 1838 static inline bool sk_has_allocations(const struct sock *sk) 1839 { 1840 return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk); 1841 } 1842 1843 /** 1844 * wq_has_sleeper - check if there are any waiting processes 1845 * @wq: struct socket_wq 1846 * 1847 * Returns true if socket_wq has waiting processes 1848 * 1849 * The purpose of the wq_has_sleeper and sock_poll_wait is to wrap the memory 1850 * barrier call. They were added due to the race found within the tcp code. 1851 * 1852 * Consider following tcp code paths: 1853 * 1854 * CPU1 CPU2 1855 * 1856 * sys_select receive packet 1857 * ... ... 1858 * __add_wait_queue update tp->rcv_nxt 1859 * ... ... 1860 * tp->rcv_nxt check sock_def_readable 1861 * ... { 1862 * schedule rcu_read_lock(); 1863 * wq = rcu_dereference(sk->sk_wq); 1864 * if (wq && waitqueue_active(&wq->wait)) 1865 * wake_up_interruptible(&wq->wait) 1866 * ... 1867 * } 1868 * 1869 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay 1870 * in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1 1871 * could then endup calling schedule and sleep forever if there are no more 1872 * data on the socket. 1873 * 1874 */ 1875 static inline bool wq_has_sleeper(struct socket_wq *wq) 1876 { 1877 /* We need to be sure we are in sync with the 1878 * add_wait_queue modifications to the wait queue. 1879 * 1880 * This memory barrier is paired in the sock_poll_wait. 1881 */ 1882 smp_mb(); 1883 return wq && waitqueue_active(&wq->wait); 1884 } 1885 1886 /** 1887 * sock_poll_wait - place memory barrier behind the poll_wait call. 1888 * @filp: file 1889 * @wait_address: socket wait queue 1890 * @p: poll_table 1891 * 1892 * See the comments in the wq_has_sleeper function. 1893 */ 1894 static inline void sock_poll_wait(struct file *filp, 1895 wait_queue_head_t *wait_address, poll_table *p) 1896 { 1897 if (!poll_does_not_wait(p) && wait_address) { 1898 poll_wait(filp, wait_address, p); 1899 /* We need to be sure we are in sync with the 1900 * socket flags modification. 1901 * 1902 * This memory barrier is paired in the wq_has_sleeper. 1903 */ 1904 smp_mb(); 1905 } 1906 } 1907 1908 /* 1909 * Queue a received datagram if it will fit. Stream and sequenced 1910 * protocols can't normally use this as they need to fit buffers in 1911 * and play with them. 1912 * 1913 * Inlined as it's very short and called for pretty much every 1914 * packet ever received. 1915 */ 1916 1917 static inline void skb_set_owner_w(struct sk_buff *skb, struct sock *sk) 1918 { 1919 skb_orphan(skb); 1920 skb->sk = sk; 1921 skb->destructor = sock_wfree; 1922 /* 1923 * We used to take a refcount on sk, but following operation 1924 * is enough to guarantee sk_free() wont free this sock until 1925 * all in-flight packets are completed 1926 */ 1927 atomic_add(skb->truesize, &sk->sk_wmem_alloc); 1928 } 1929 1930 static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk) 1931 { 1932 skb_orphan(skb); 1933 skb->sk = sk; 1934 skb->destructor = sock_rfree; 1935 atomic_add(skb->truesize, &sk->sk_rmem_alloc); 1936 sk_mem_charge(sk, skb->truesize); 1937 } 1938 1939 extern void sk_reset_timer(struct sock *sk, struct timer_list *timer, 1940 unsigned long expires); 1941 1942 extern void sk_stop_timer(struct sock *sk, struct timer_list *timer); 1943 1944 extern int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb); 1945 1946 extern int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb); 1947 1948 /* 1949 * Recover an error report and clear atomically 1950 */ 1951 1952 static inline int sock_error(struct sock *sk) 1953 { 1954 int err; 1955 if (likely(!sk->sk_err)) 1956 return 0; 1957 err = xchg(&sk->sk_err, 0); 1958 return -err; 1959 } 1960 1961 static inline unsigned long sock_wspace(struct sock *sk) 1962 { 1963 int amt = 0; 1964 1965 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) { 1966 amt = sk->sk_sndbuf - atomic_read(&sk->sk_wmem_alloc); 1967 if (amt < 0) 1968 amt = 0; 1969 } 1970 return amt; 1971 } 1972 1973 static inline void sk_wake_async(struct sock *sk, int how, int band) 1974 { 1975 if (sock_flag(sk, SOCK_FASYNC)) 1976 sock_wake_async(sk->sk_socket, how, band); 1977 } 1978 1979 #define SOCK_MIN_SNDBUF 2048 1980 /* 1981 * Since sk_rmem_alloc sums skb->truesize, even a small frame might need 1982 * sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak 1983 */ 1984 #define SOCK_MIN_RCVBUF (2048 + sizeof(struct sk_buff)) 1985 1986 static inline void sk_stream_moderate_sndbuf(struct sock *sk) 1987 { 1988 if (!(sk->sk_userlocks & SOCK_SNDBUF_LOCK)) { 1989 sk->sk_sndbuf = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1); 1990 sk->sk_sndbuf = max(sk->sk_sndbuf, SOCK_MIN_SNDBUF); 1991 } 1992 } 1993 1994 struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp); 1995 1996 static inline struct page *sk_stream_alloc_page(struct sock *sk) 1997 { 1998 struct page *page = NULL; 1999 2000 page = alloc_pages(sk->sk_allocation, 0); 2001 if (!page) { 2002 sk_enter_memory_pressure(sk); 2003 sk_stream_moderate_sndbuf(sk); 2004 } 2005 return page; 2006 } 2007 2008 /* 2009 * Default write policy as shown to user space via poll/select/SIGIO 2010 */ 2011 static inline bool sock_writeable(const struct sock *sk) 2012 { 2013 return atomic_read(&sk->sk_wmem_alloc) < (sk->sk_sndbuf >> 1); 2014 } 2015 2016 static inline gfp_t gfp_any(void) 2017 { 2018 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL; 2019 } 2020 2021 static inline long sock_rcvtimeo(const struct sock *sk, bool noblock) 2022 { 2023 return noblock ? 0 : sk->sk_rcvtimeo; 2024 } 2025 2026 static inline long sock_sndtimeo(const struct sock *sk, bool noblock) 2027 { 2028 return noblock ? 0 : sk->sk_sndtimeo; 2029 } 2030 2031 static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len) 2032 { 2033 return (waitall ? len : min_t(int, sk->sk_rcvlowat, len)) ? : 1; 2034 } 2035 2036 /* Alas, with timeout socket operations are not restartable. 2037 * Compare this to poll(). 2038 */ 2039 static inline int sock_intr_errno(long timeo) 2040 { 2041 return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR; 2042 } 2043 2044 extern void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk, 2045 struct sk_buff *skb); 2046 extern void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk, 2047 struct sk_buff *skb); 2048 2049 static inline void 2050 sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb) 2051 { 2052 ktime_t kt = skb->tstamp; 2053 struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb); 2054 2055 /* 2056 * generate control messages if 2057 * - receive time stamping in software requested (SOCK_RCVTSTAMP 2058 * or SOCK_TIMESTAMPING_RX_SOFTWARE) 2059 * - software time stamp available and wanted 2060 * (SOCK_TIMESTAMPING_SOFTWARE) 2061 * - hardware time stamps available and wanted 2062 * (SOCK_TIMESTAMPING_SYS_HARDWARE or 2063 * SOCK_TIMESTAMPING_RAW_HARDWARE) 2064 */ 2065 if (sock_flag(sk, SOCK_RCVTSTAMP) || 2066 sock_flag(sk, SOCK_TIMESTAMPING_RX_SOFTWARE) || 2067 (kt.tv64 && sock_flag(sk, SOCK_TIMESTAMPING_SOFTWARE)) || 2068 (hwtstamps->hwtstamp.tv64 && 2069 sock_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE)) || 2070 (hwtstamps->syststamp.tv64 && 2071 sock_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE))) 2072 __sock_recv_timestamp(msg, sk, skb); 2073 else 2074 sk->sk_stamp = kt; 2075 2076 if (sock_flag(sk, SOCK_WIFI_STATUS) && skb->wifi_acked_valid) 2077 __sock_recv_wifi_status(msg, sk, skb); 2078 } 2079 2080 extern void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk, 2081 struct sk_buff *skb); 2082 2083 static inline void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk, 2084 struct sk_buff *skb) 2085 { 2086 #define FLAGS_TS_OR_DROPS ((1UL << SOCK_RXQ_OVFL) | \ 2087 (1UL << SOCK_RCVTSTAMP) | \ 2088 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE) | \ 2089 (1UL << SOCK_TIMESTAMPING_SOFTWARE) | \ 2090 (1UL << SOCK_TIMESTAMPING_RAW_HARDWARE) | \ 2091 (1UL << SOCK_TIMESTAMPING_SYS_HARDWARE)) 2092 2093 if (sk->sk_flags & FLAGS_TS_OR_DROPS) 2094 __sock_recv_ts_and_drops(msg, sk, skb); 2095 else 2096 sk->sk_stamp = skb->tstamp; 2097 } 2098 2099 /** 2100 * sock_tx_timestamp - checks whether the outgoing packet is to be time stamped 2101 * @sk: socket sending this packet 2102 * @tx_flags: filled with instructions for time stamping 2103 * 2104 * Currently only depends on SOCK_TIMESTAMPING* flags. Returns error code if 2105 * parameters are invalid. 2106 */ 2107 extern int sock_tx_timestamp(struct sock *sk, __u8 *tx_flags); 2108 2109 /** 2110 * sk_eat_skb - Release a skb if it is no longer needed 2111 * @sk: socket to eat this skb from 2112 * @skb: socket buffer to eat 2113 * @copied_early: flag indicating whether DMA operations copied this data early 2114 * 2115 * This routine must be called with interrupts disabled or with the socket 2116 * locked so that the sk_buff queue operation is ok. 2117 */ 2118 #ifdef CONFIG_NET_DMA 2119 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb, bool copied_early) 2120 { 2121 __skb_unlink(skb, &sk->sk_receive_queue); 2122 if (!copied_early) 2123 __kfree_skb(skb); 2124 else 2125 __skb_queue_tail(&sk->sk_async_wait_queue, skb); 2126 } 2127 #else 2128 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb, bool copied_early) 2129 { 2130 __skb_unlink(skb, &sk->sk_receive_queue); 2131 __kfree_skb(skb); 2132 } 2133 #endif 2134 2135 static inline 2136 struct net *sock_net(const struct sock *sk) 2137 { 2138 return read_pnet(&sk->sk_net); 2139 } 2140 2141 static inline 2142 void sock_net_set(struct sock *sk, struct net *net) 2143 { 2144 write_pnet(&sk->sk_net, net); 2145 } 2146 2147 /* 2148 * Kernel sockets, f.e. rtnl or icmp_socket, are a part of a namespace. 2149 * They should not hold a reference to a namespace in order to allow 2150 * to stop it. 2151 * Sockets after sk_change_net should be released using sk_release_kernel 2152 */ 2153 static inline void sk_change_net(struct sock *sk, struct net *net) 2154 { 2155 put_net(sock_net(sk)); 2156 sock_net_set(sk, hold_net(net)); 2157 } 2158 2159 static inline struct sock *skb_steal_sock(struct sk_buff *skb) 2160 { 2161 if (skb->sk) { 2162 struct sock *sk = skb->sk; 2163 2164 skb->destructor = NULL; 2165 skb->sk = NULL; 2166 return sk; 2167 } 2168 return NULL; 2169 } 2170 2171 extern void sock_enable_timestamp(struct sock *sk, int flag); 2172 extern int sock_get_timestamp(struct sock *, struct timeval __user *); 2173 extern int sock_get_timestampns(struct sock *, struct timespec __user *); 2174 2175 /* 2176 * Enable debug/info messages 2177 */ 2178 extern int net_msg_warn; 2179 #define NETDEBUG(fmt, args...) \ 2180 do { if (net_msg_warn) printk(fmt,##args); } while (0) 2181 2182 #define LIMIT_NETDEBUG(fmt, args...) \ 2183 do { if (net_msg_warn && net_ratelimit()) printk(fmt,##args); } while(0) 2184 2185 extern __u32 sysctl_wmem_max; 2186 extern __u32 sysctl_rmem_max; 2187 2188 extern void sk_init(void); 2189 2190 extern int sysctl_optmem_max; 2191 2192 extern __u32 sysctl_wmem_default; 2193 extern __u32 sysctl_rmem_default; 2194 2195 #endif /* _SOCK_H */ 2196