1 /* 2 * INET An implementation of the TCP/IP protocol suite for the LINUX 3 * operating system. INET is implemented using the BSD Socket 4 * interface as the means of communication with the user level. 5 * 6 * Definitions for the AF_INET socket handler. 7 * 8 * Version: @(#)sock.h 1.0.4 05/13/93 9 * 10 * Authors: Ross Biro 11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> 12 * Corey Minyard <wf-rch!minyard@relay.EU.net> 13 * Florian La Roche <flla@stud.uni-sb.de> 14 * 15 * Fixes: 16 * Alan Cox : Volatiles in skbuff pointers. See 17 * skbuff comments. May be overdone, 18 * better to prove they can be removed 19 * than the reverse. 20 * Alan Cox : Added a zapped field for tcp to note 21 * a socket is reset and must stay shut up 22 * Alan Cox : New fields for options 23 * Pauline Middelink : identd support 24 * Alan Cox : Eliminate low level recv/recvfrom 25 * David S. Miller : New socket lookup architecture. 26 * Steve Whitehouse: Default routines for sock_ops 27 * Arnaldo C. Melo : removed net_pinfo, tp_pinfo and made 28 * protinfo be just a void pointer, as the 29 * protocol specific parts were moved to 30 * respective headers and ipv4/v6, etc now 31 * use private slabcaches for its socks 32 * Pedro Hortas : New flags field for socket options 33 * 34 * 35 * This program is free software; you can redistribute it and/or 36 * modify it under the terms of the GNU General Public License 37 * as published by the Free Software Foundation; either version 38 * 2 of the License, or (at your option) any later version. 39 */ 40 #ifndef _SOCK_H 41 #define _SOCK_H 42 43 #include <linux/hardirq.h> 44 #include <linux/kernel.h> 45 #include <linux/list.h> 46 #include <linux/list_nulls.h> 47 #include <linux/timer.h> 48 #include <linux/cache.h> 49 #include <linux/bitops.h> 50 #include <linux/lockdep.h> 51 #include <linux/netdevice.h> 52 #include <linux/skbuff.h> /* struct sk_buff */ 53 #include <linux/mm.h> 54 #include <linux/security.h> 55 #include <linux/slab.h> 56 #include <linux/uaccess.h> 57 #include <linux/memcontrol.h> 58 #include <linux/res_counter.h> 59 #include <linux/static_key.h> 60 #include <linux/aio.h> 61 #include <linux/sched.h> 62 63 #include <linux/filter.h> 64 #include <linux/rculist_nulls.h> 65 #include <linux/poll.h> 66 67 #include <linux/atomic.h> 68 #include <net/dst.h> 69 #include <net/checksum.h> 70 71 struct cgroup; 72 struct cgroup_subsys; 73 #ifdef CONFIG_NET 74 int mem_cgroup_sockets_init(struct mem_cgroup *memcg, struct cgroup_subsys *ss); 75 void mem_cgroup_sockets_destroy(struct mem_cgroup *memcg); 76 #else 77 static inline 78 int mem_cgroup_sockets_init(struct mem_cgroup *memcg, struct cgroup_subsys *ss) 79 { 80 return 0; 81 } 82 static inline 83 void mem_cgroup_sockets_destroy(struct mem_cgroup *memcg) 84 { 85 } 86 #endif 87 /* 88 * This structure really needs to be cleaned up. 89 * Most of it is for TCP, and not used by any of 90 * the other protocols. 91 */ 92 93 /* Define this to get the SOCK_DBG debugging facility. */ 94 #define SOCK_DEBUGGING 95 #ifdef SOCK_DEBUGGING 96 #define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \ 97 printk(KERN_DEBUG msg); } while (0) 98 #else 99 /* Validate arguments and do nothing */ 100 static inline __printf(2, 3) 101 void SOCK_DEBUG(const struct sock *sk, const char *msg, ...) 102 { 103 } 104 #endif 105 106 /* This is the per-socket lock. The spinlock provides a synchronization 107 * between user contexts and software interrupt processing, whereas the 108 * mini-semaphore synchronizes multiple users amongst themselves. 109 */ 110 typedef struct { 111 spinlock_t slock; 112 int owned; 113 wait_queue_head_t wq; 114 /* 115 * We express the mutex-alike socket_lock semantics 116 * to the lock validator by explicitly managing 117 * the slock as a lock variant (in addition to 118 * the slock itself): 119 */ 120 #ifdef CONFIG_DEBUG_LOCK_ALLOC 121 struct lockdep_map dep_map; 122 #endif 123 } socket_lock_t; 124 125 struct sock; 126 struct proto; 127 struct net; 128 129 /** 130 * struct sock_common - minimal network layer representation of sockets 131 * @skc_daddr: Foreign IPv4 addr 132 * @skc_rcv_saddr: Bound local IPv4 addr 133 * @skc_hash: hash value used with various protocol lookup tables 134 * @skc_u16hashes: two u16 hash values used by UDP lookup tables 135 * @skc_family: network address family 136 * @skc_state: Connection state 137 * @skc_reuse: %SO_REUSEADDR setting 138 * @skc_bound_dev_if: bound device index if != 0 139 * @skc_bind_node: bind hash linkage for various protocol lookup tables 140 * @skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol 141 * @skc_prot: protocol handlers inside a network family 142 * @skc_net: reference to the network namespace of this socket 143 * @skc_node: main hash linkage for various protocol lookup tables 144 * @skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol 145 * @skc_tx_queue_mapping: tx queue number for this connection 146 * @skc_refcnt: reference count 147 * 148 * This is the minimal network layer representation of sockets, the header 149 * for struct sock and struct inet_timewait_sock. 150 */ 151 struct sock_common { 152 /* skc_daddr and skc_rcv_saddr must be grouped : 153 * cf INET_MATCH() and INET_TW_MATCH() 154 */ 155 __be32 skc_daddr; 156 __be32 skc_rcv_saddr; 157 158 union { 159 unsigned int skc_hash; 160 __u16 skc_u16hashes[2]; 161 }; 162 unsigned short skc_family; 163 volatile unsigned char skc_state; 164 unsigned char skc_reuse; 165 int skc_bound_dev_if; 166 union { 167 struct hlist_node skc_bind_node; 168 struct hlist_nulls_node skc_portaddr_node; 169 }; 170 struct proto *skc_prot; 171 #ifdef CONFIG_NET_NS 172 struct net *skc_net; 173 #endif 174 /* 175 * fields between dontcopy_begin/dontcopy_end 176 * are not copied in sock_copy() 177 */ 178 /* private: */ 179 int skc_dontcopy_begin[0]; 180 /* public: */ 181 union { 182 struct hlist_node skc_node; 183 struct hlist_nulls_node skc_nulls_node; 184 }; 185 int skc_tx_queue_mapping; 186 atomic_t skc_refcnt; 187 /* private: */ 188 int skc_dontcopy_end[0]; 189 /* public: */ 190 }; 191 192 struct cg_proto; 193 /** 194 * struct sock - network layer representation of sockets 195 * @__sk_common: shared layout with inet_timewait_sock 196 * @sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN 197 * @sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings 198 * @sk_lock: synchronizer 199 * @sk_rcvbuf: size of receive buffer in bytes 200 * @sk_wq: sock wait queue and async head 201 * @sk_rx_dst: receive input route used by early tcp demux 202 * @sk_dst_cache: destination cache 203 * @sk_dst_lock: destination cache lock 204 * @sk_policy: flow policy 205 * @sk_receive_queue: incoming packets 206 * @sk_wmem_alloc: transmit queue bytes committed 207 * @sk_write_queue: Packet sending queue 208 * @sk_async_wait_queue: DMA copied packets 209 * @sk_omem_alloc: "o" is "option" or "other" 210 * @sk_wmem_queued: persistent queue size 211 * @sk_forward_alloc: space allocated forward 212 * @sk_allocation: allocation mode 213 * @sk_sndbuf: size of send buffer in bytes 214 * @sk_flags: %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE, 215 * %SO_OOBINLINE settings, %SO_TIMESTAMPING settings 216 * @sk_no_check: %SO_NO_CHECK setting, wether or not checkup packets 217 * @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO) 218 * @sk_route_nocaps: forbidden route capabilities (e.g NETIF_F_GSO_MASK) 219 * @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4) 220 * @sk_gso_max_size: Maximum GSO segment size to build 221 * @sk_gso_max_segs: Maximum number of GSO segments 222 * @sk_lingertime: %SO_LINGER l_linger setting 223 * @sk_backlog: always used with the per-socket spinlock held 224 * @sk_callback_lock: used with the callbacks in the end of this struct 225 * @sk_error_queue: rarely used 226 * @sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt, 227 * IPV6_ADDRFORM for instance) 228 * @sk_err: last error 229 * @sk_err_soft: errors that don't cause failure but are the cause of a 230 * persistent failure not just 'timed out' 231 * @sk_drops: raw/udp drops counter 232 * @sk_ack_backlog: current listen backlog 233 * @sk_max_ack_backlog: listen backlog set in listen() 234 * @sk_priority: %SO_PRIORITY setting 235 * @sk_cgrp_prioidx: socket group's priority map index 236 * @sk_type: socket type (%SOCK_STREAM, etc) 237 * @sk_protocol: which protocol this socket belongs in this network family 238 * @sk_peer_pid: &struct pid for this socket's peer 239 * @sk_peer_cred: %SO_PEERCRED setting 240 * @sk_rcvlowat: %SO_RCVLOWAT setting 241 * @sk_rcvtimeo: %SO_RCVTIMEO setting 242 * @sk_sndtimeo: %SO_SNDTIMEO setting 243 * @sk_rxhash: flow hash received from netif layer 244 * @sk_filter: socket filtering instructions 245 * @sk_protinfo: private area, net family specific, when not using slab 246 * @sk_timer: sock cleanup timer 247 * @sk_stamp: time stamp of last packet received 248 * @sk_socket: Identd and reporting IO signals 249 * @sk_user_data: RPC layer private data 250 * @sk_frag: cached page frag 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 u16 sk_gso_max_segs; 342 int sk_rcvlowat; 343 unsigned long sk_lingertime; 344 struct sk_buff_head sk_error_queue; 345 struct proto *sk_prot_creator; 346 rwlock_t sk_callback_lock; 347 int sk_err, 348 sk_err_soft; 349 unsigned short sk_ack_backlog; 350 unsigned short sk_max_ack_backlog; 351 __u32 sk_priority; 352 #ifdef CONFIG_CGROUPS 353 __u32 sk_cgrp_prioidx; 354 #endif 355 struct pid *sk_peer_pid; 356 const struct cred *sk_peer_cred; 357 long sk_rcvtimeo; 358 long sk_sndtimeo; 359 void *sk_protinfo; 360 struct timer_list sk_timer; 361 ktime_t sk_stamp; 362 struct socket *sk_socket; 363 void *sk_user_data; 364 struct page_frag sk_frag; 365 struct sk_buff *sk_send_head; 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 static inline struct user_namespace *sk_user_ns(struct sock *sk) 608 { 609 /* Careful only use this in a context where these parameters 610 * can not change and must all be valid, such as recvmsg from 611 * userspace. 612 */ 613 return sk->sk_socket->file->f_cred->user_ns; 614 } 615 616 /* Sock flags */ 617 enum sock_flags { 618 SOCK_DEAD, 619 SOCK_DONE, 620 SOCK_URGINLINE, 621 SOCK_KEEPOPEN, 622 SOCK_LINGER, 623 SOCK_DESTROY, 624 SOCK_BROADCAST, 625 SOCK_TIMESTAMP, 626 SOCK_ZAPPED, 627 SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */ 628 SOCK_DBG, /* %SO_DEBUG setting */ 629 SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */ 630 SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */ 631 SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */ 632 SOCK_QUEUE_SHRUNK, /* write queue has been shrunk recently */ 633 SOCK_MEMALLOC, /* VM depends on this socket for swapping */ 634 SOCK_TIMESTAMPING_TX_HARDWARE, /* %SOF_TIMESTAMPING_TX_HARDWARE */ 635 SOCK_TIMESTAMPING_TX_SOFTWARE, /* %SOF_TIMESTAMPING_TX_SOFTWARE */ 636 SOCK_TIMESTAMPING_RX_HARDWARE, /* %SOF_TIMESTAMPING_RX_HARDWARE */ 637 SOCK_TIMESTAMPING_RX_SOFTWARE, /* %SOF_TIMESTAMPING_RX_SOFTWARE */ 638 SOCK_TIMESTAMPING_SOFTWARE, /* %SOF_TIMESTAMPING_SOFTWARE */ 639 SOCK_TIMESTAMPING_RAW_HARDWARE, /* %SOF_TIMESTAMPING_RAW_HARDWARE */ 640 SOCK_TIMESTAMPING_SYS_HARDWARE, /* %SOF_TIMESTAMPING_SYS_HARDWARE */ 641 SOCK_FASYNC, /* fasync() active */ 642 SOCK_RXQ_OVFL, 643 SOCK_ZEROCOPY, /* buffers from userspace */ 644 SOCK_WIFI_STATUS, /* push wifi status to userspace */ 645 SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS. 646 * Will use last 4 bytes of packet sent from 647 * user-space instead. 648 */ 649 }; 650 651 static inline void sock_copy_flags(struct sock *nsk, struct sock *osk) 652 { 653 nsk->sk_flags = osk->sk_flags; 654 } 655 656 static inline void sock_set_flag(struct sock *sk, enum sock_flags flag) 657 { 658 __set_bit(flag, &sk->sk_flags); 659 } 660 661 static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag) 662 { 663 __clear_bit(flag, &sk->sk_flags); 664 } 665 666 static inline bool sock_flag(const struct sock *sk, enum sock_flags flag) 667 { 668 return test_bit(flag, &sk->sk_flags); 669 } 670 671 #ifdef CONFIG_NET 672 extern struct static_key memalloc_socks; 673 static inline int sk_memalloc_socks(void) 674 { 675 return static_key_false(&memalloc_socks); 676 } 677 #else 678 679 static inline int sk_memalloc_socks(void) 680 { 681 return 0; 682 } 683 684 #endif 685 686 static inline gfp_t sk_gfp_atomic(struct sock *sk, gfp_t gfp_mask) 687 { 688 return GFP_ATOMIC | (sk->sk_allocation & __GFP_MEMALLOC); 689 } 690 691 static inline void sk_acceptq_removed(struct sock *sk) 692 { 693 sk->sk_ack_backlog--; 694 } 695 696 static inline void sk_acceptq_added(struct sock *sk) 697 { 698 sk->sk_ack_backlog++; 699 } 700 701 static inline bool sk_acceptq_is_full(const struct sock *sk) 702 { 703 return sk->sk_ack_backlog > sk->sk_max_ack_backlog; 704 } 705 706 /* 707 * Compute minimal free write space needed to queue new packets. 708 */ 709 static inline int sk_stream_min_wspace(const struct sock *sk) 710 { 711 return sk->sk_wmem_queued >> 1; 712 } 713 714 static inline int sk_stream_wspace(const struct sock *sk) 715 { 716 return sk->sk_sndbuf - sk->sk_wmem_queued; 717 } 718 719 extern void sk_stream_write_space(struct sock *sk); 720 721 static inline bool sk_stream_memory_free(const struct sock *sk) 722 { 723 return sk->sk_wmem_queued < sk->sk_sndbuf; 724 } 725 726 /* OOB backlog add */ 727 static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb) 728 { 729 /* dont let skb dst not refcounted, we are going to leave rcu lock */ 730 skb_dst_force(skb); 731 732 if (!sk->sk_backlog.tail) 733 sk->sk_backlog.head = skb; 734 else 735 sk->sk_backlog.tail->next = skb; 736 737 sk->sk_backlog.tail = skb; 738 skb->next = NULL; 739 } 740 741 /* 742 * Take into account size of receive queue and backlog queue 743 * Do not take into account this skb truesize, 744 * to allow even a single big packet to come. 745 */ 746 static inline bool sk_rcvqueues_full(const struct sock *sk, const struct sk_buff *skb, 747 unsigned int limit) 748 { 749 unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc); 750 751 return qsize > limit; 752 } 753 754 /* The per-socket spinlock must be held here. */ 755 static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb, 756 unsigned int limit) 757 { 758 if (sk_rcvqueues_full(sk, skb, limit)) 759 return -ENOBUFS; 760 761 __sk_add_backlog(sk, skb); 762 sk->sk_backlog.len += skb->truesize; 763 return 0; 764 } 765 766 extern int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb); 767 768 static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb) 769 { 770 if (sk_memalloc_socks() && skb_pfmemalloc(skb)) 771 return __sk_backlog_rcv(sk, skb); 772 773 return sk->sk_backlog_rcv(sk, skb); 774 } 775 776 static inline void sock_rps_record_flow(const struct sock *sk) 777 { 778 #ifdef CONFIG_RPS 779 struct rps_sock_flow_table *sock_flow_table; 780 781 rcu_read_lock(); 782 sock_flow_table = rcu_dereference(rps_sock_flow_table); 783 rps_record_sock_flow(sock_flow_table, sk->sk_rxhash); 784 rcu_read_unlock(); 785 #endif 786 } 787 788 static inline void sock_rps_reset_flow(const struct sock *sk) 789 { 790 #ifdef CONFIG_RPS 791 struct rps_sock_flow_table *sock_flow_table; 792 793 rcu_read_lock(); 794 sock_flow_table = rcu_dereference(rps_sock_flow_table); 795 rps_reset_sock_flow(sock_flow_table, sk->sk_rxhash); 796 rcu_read_unlock(); 797 #endif 798 } 799 800 static inline void sock_rps_save_rxhash(struct sock *sk, 801 const struct sk_buff *skb) 802 { 803 #ifdef CONFIG_RPS 804 if (unlikely(sk->sk_rxhash != skb->rxhash)) { 805 sock_rps_reset_flow(sk); 806 sk->sk_rxhash = skb->rxhash; 807 } 808 #endif 809 } 810 811 static inline void sock_rps_reset_rxhash(struct sock *sk) 812 { 813 #ifdef CONFIG_RPS 814 sock_rps_reset_flow(sk); 815 sk->sk_rxhash = 0; 816 #endif 817 } 818 819 #define sk_wait_event(__sk, __timeo, __condition) \ 820 ({ int __rc; \ 821 release_sock(__sk); \ 822 __rc = __condition; \ 823 if (!__rc) { \ 824 *(__timeo) = schedule_timeout(*(__timeo)); \ 825 } \ 826 lock_sock(__sk); \ 827 __rc = __condition; \ 828 __rc; \ 829 }) 830 831 extern int sk_stream_wait_connect(struct sock *sk, long *timeo_p); 832 extern int sk_stream_wait_memory(struct sock *sk, long *timeo_p); 833 extern void sk_stream_wait_close(struct sock *sk, long timeo_p); 834 extern int sk_stream_error(struct sock *sk, int flags, int err); 835 extern void sk_stream_kill_queues(struct sock *sk); 836 extern void sk_set_memalloc(struct sock *sk); 837 extern void sk_clear_memalloc(struct sock *sk); 838 839 extern int sk_wait_data(struct sock *sk, long *timeo); 840 841 struct request_sock_ops; 842 struct timewait_sock_ops; 843 struct inet_hashinfo; 844 struct raw_hashinfo; 845 struct module; 846 847 /* Networking protocol blocks we attach to sockets. 848 * socket layer -> transport layer interface 849 * transport -> network interface is defined by struct inet_proto 850 */ 851 struct proto { 852 void (*close)(struct sock *sk, 853 long timeout); 854 int (*connect)(struct sock *sk, 855 struct sockaddr *uaddr, 856 int addr_len); 857 int (*disconnect)(struct sock *sk, int flags); 858 859 struct sock * (*accept)(struct sock *sk, int flags, int *err); 860 861 int (*ioctl)(struct sock *sk, int cmd, 862 unsigned long arg); 863 int (*init)(struct sock *sk); 864 void (*destroy)(struct sock *sk); 865 void (*shutdown)(struct sock *sk, int how); 866 int (*setsockopt)(struct sock *sk, int level, 867 int optname, char __user *optval, 868 unsigned int optlen); 869 int (*getsockopt)(struct sock *sk, int level, 870 int optname, char __user *optval, 871 int __user *option); 872 #ifdef CONFIG_COMPAT 873 int (*compat_setsockopt)(struct sock *sk, 874 int level, 875 int optname, char __user *optval, 876 unsigned int optlen); 877 int (*compat_getsockopt)(struct sock *sk, 878 int level, 879 int optname, char __user *optval, 880 int __user *option); 881 int (*compat_ioctl)(struct sock *sk, 882 unsigned int cmd, unsigned long arg); 883 #endif 884 int (*sendmsg)(struct kiocb *iocb, struct sock *sk, 885 struct msghdr *msg, size_t len); 886 int (*recvmsg)(struct kiocb *iocb, struct sock *sk, 887 struct msghdr *msg, 888 size_t len, int noblock, int flags, 889 int *addr_len); 890 int (*sendpage)(struct sock *sk, struct page *page, 891 int offset, size_t size, int flags); 892 int (*bind)(struct sock *sk, 893 struct sockaddr *uaddr, int addr_len); 894 895 int (*backlog_rcv) (struct sock *sk, 896 struct sk_buff *skb); 897 898 void (*release_cb)(struct sock *sk); 899 void (*mtu_reduced)(struct sock *sk); 900 901 /* Keeping track of sk's, looking them up, and port selection methods. */ 902 void (*hash)(struct sock *sk); 903 void (*unhash)(struct sock *sk); 904 void (*rehash)(struct sock *sk); 905 int (*get_port)(struct sock *sk, unsigned short snum); 906 void (*clear_sk)(struct sock *sk, int size); 907 908 /* Keeping track of sockets in use */ 909 #ifdef CONFIG_PROC_FS 910 unsigned int inuse_idx; 911 #endif 912 913 /* Memory pressure */ 914 void (*enter_memory_pressure)(struct sock *sk); 915 atomic_long_t *memory_allocated; /* Current allocated memory. */ 916 struct percpu_counter *sockets_allocated; /* Current number of sockets. */ 917 /* 918 * Pressure flag: try to collapse. 919 * Technical note: it is used by multiple contexts non atomically. 920 * All the __sk_mem_schedule() is of this nature: accounting 921 * is strict, actions are advisory and have some latency. 922 */ 923 int *memory_pressure; 924 long *sysctl_mem; 925 int *sysctl_wmem; 926 int *sysctl_rmem; 927 int max_header; 928 bool no_autobind; 929 930 struct kmem_cache *slab; 931 unsigned int obj_size; 932 int slab_flags; 933 934 struct percpu_counter *orphan_count; 935 936 struct request_sock_ops *rsk_prot; 937 struct timewait_sock_ops *twsk_prot; 938 939 union { 940 struct inet_hashinfo *hashinfo; 941 struct udp_table *udp_table; 942 struct raw_hashinfo *raw_hash; 943 } h; 944 945 struct module *owner; 946 947 char name[32]; 948 949 struct list_head node; 950 #ifdef SOCK_REFCNT_DEBUG 951 atomic_t socks; 952 #endif 953 #ifdef CONFIG_MEMCG_KMEM 954 /* 955 * cgroup specific init/deinit functions. Called once for all 956 * protocols that implement it, from cgroups populate function. 957 * This function has to setup any files the protocol want to 958 * appear in the kmem cgroup filesystem. 959 */ 960 int (*init_cgroup)(struct mem_cgroup *memcg, 961 struct cgroup_subsys *ss); 962 void (*destroy_cgroup)(struct mem_cgroup *memcg); 963 struct cg_proto *(*proto_cgroup)(struct mem_cgroup *memcg); 964 #endif 965 }; 966 967 /* 968 * Bits in struct cg_proto.flags 969 */ 970 enum cg_proto_flags { 971 /* Currently active and new sockets should be assigned to cgroups */ 972 MEMCG_SOCK_ACTIVE, 973 /* It was ever activated; we must disarm static keys on destruction */ 974 MEMCG_SOCK_ACTIVATED, 975 }; 976 977 struct cg_proto { 978 void (*enter_memory_pressure)(struct sock *sk); 979 struct res_counter *memory_allocated; /* Current allocated memory. */ 980 struct percpu_counter *sockets_allocated; /* Current number of sockets. */ 981 int *memory_pressure; 982 long *sysctl_mem; 983 unsigned long flags; 984 /* 985 * memcg field is used to find which memcg we belong directly 986 * Each memcg struct can hold more than one cg_proto, so container_of 987 * won't really cut. 988 * 989 * The elegant solution would be having an inverse function to 990 * proto_cgroup in struct proto, but that means polluting the structure 991 * for everybody, instead of just for memcg users. 992 */ 993 struct mem_cgroup *memcg; 994 }; 995 996 extern int proto_register(struct proto *prot, int alloc_slab); 997 extern void proto_unregister(struct proto *prot); 998 999 static inline bool memcg_proto_active(struct cg_proto *cg_proto) 1000 { 1001 return test_bit(MEMCG_SOCK_ACTIVE, &cg_proto->flags); 1002 } 1003 1004 static inline bool memcg_proto_activated(struct cg_proto *cg_proto) 1005 { 1006 return test_bit(MEMCG_SOCK_ACTIVATED, &cg_proto->flags); 1007 } 1008 1009 #ifdef SOCK_REFCNT_DEBUG 1010 static inline void sk_refcnt_debug_inc(struct sock *sk) 1011 { 1012 atomic_inc(&sk->sk_prot->socks); 1013 } 1014 1015 static inline void sk_refcnt_debug_dec(struct sock *sk) 1016 { 1017 atomic_dec(&sk->sk_prot->socks); 1018 printk(KERN_DEBUG "%s socket %p released, %d are still alive\n", 1019 sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks)); 1020 } 1021 1022 inline void sk_refcnt_debug_release(const struct sock *sk) 1023 { 1024 if (atomic_read(&sk->sk_refcnt) != 1) 1025 printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n", 1026 sk->sk_prot->name, sk, atomic_read(&sk->sk_refcnt)); 1027 } 1028 #else /* SOCK_REFCNT_DEBUG */ 1029 #define sk_refcnt_debug_inc(sk) do { } while (0) 1030 #define sk_refcnt_debug_dec(sk) do { } while (0) 1031 #define sk_refcnt_debug_release(sk) do { } while (0) 1032 #endif /* SOCK_REFCNT_DEBUG */ 1033 1034 #if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_NET) 1035 extern struct static_key memcg_socket_limit_enabled; 1036 static inline struct cg_proto *parent_cg_proto(struct proto *proto, 1037 struct cg_proto *cg_proto) 1038 { 1039 return proto->proto_cgroup(parent_mem_cgroup(cg_proto->memcg)); 1040 } 1041 #define mem_cgroup_sockets_enabled static_key_false(&memcg_socket_limit_enabled) 1042 #else 1043 #define mem_cgroup_sockets_enabled 0 1044 static inline struct cg_proto *parent_cg_proto(struct proto *proto, 1045 struct cg_proto *cg_proto) 1046 { 1047 return NULL; 1048 } 1049 #endif 1050 1051 1052 static inline bool sk_has_memory_pressure(const struct sock *sk) 1053 { 1054 return sk->sk_prot->memory_pressure != NULL; 1055 } 1056 1057 static inline bool sk_under_memory_pressure(const struct sock *sk) 1058 { 1059 if (!sk->sk_prot->memory_pressure) 1060 return false; 1061 1062 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) 1063 return !!*sk->sk_cgrp->memory_pressure; 1064 1065 return !!*sk->sk_prot->memory_pressure; 1066 } 1067 1068 static inline void sk_leave_memory_pressure(struct sock *sk) 1069 { 1070 int *memory_pressure = sk->sk_prot->memory_pressure; 1071 1072 if (!memory_pressure) 1073 return; 1074 1075 if (*memory_pressure) 1076 *memory_pressure = 0; 1077 1078 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) { 1079 struct cg_proto *cg_proto = sk->sk_cgrp; 1080 struct proto *prot = sk->sk_prot; 1081 1082 for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto)) 1083 if (*cg_proto->memory_pressure) 1084 *cg_proto->memory_pressure = 0; 1085 } 1086 1087 } 1088 1089 static inline void sk_enter_memory_pressure(struct sock *sk) 1090 { 1091 if (!sk->sk_prot->enter_memory_pressure) 1092 return; 1093 1094 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) { 1095 struct cg_proto *cg_proto = sk->sk_cgrp; 1096 struct proto *prot = sk->sk_prot; 1097 1098 for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto)) 1099 cg_proto->enter_memory_pressure(sk); 1100 } 1101 1102 sk->sk_prot->enter_memory_pressure(sk); 1103 } 1104 1105 static inline long sk_prot_mem_limits(const struct sock *sk, int index) 1106 { 1107 long *prot = sk->sk_prot->sysctl_mem; 1108 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) 1109 prot = sk->sk_cgrp->sysctl_mem; 1110 return prot[index]; 1111 } 1112 1113 static inline void memcg_memory_allocated_add(struct cg_proto *prot, 1114 unsigned long amt, 1115 int *parent_status) 1116 { 1117 struct res_counter *fail; 1118 int ret; 1119 1120 ret = res_counter_charge_nofail(prot->memory_allocated, 1121 amt << PAGE_SHIFT, &fail); 1122 if (ret < 0) 1123 *parent_status = OVER_LIMIT; 1124 } 1125 1126 static inline void memcg_memory_allocated_sub(struct cg_proto *prot, 1127 unsigned long amt) 1128 { 1129 res_counter_uncharge(prot->memory_allocated, amt << PAGE_SHIFT); 1130 } 1131 1132 static inline u64 memcg_memory_allocated_read(struct cg_proto *prot) 1133 { 1134 u64 ret; 1135 ret = res_counter_read_u64(prot->memory_allocated, RES_USAGE); 1136 return ret >> PAGE_SHIFT; 1137 } 1138 1139 static inline long 1140 sk_memory_allocated(const struct sock *sk) 1141 { 1142 struct proto *prot = sk->sk_prot; 1143 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) 1144 return memcg_memory_allocated_read(sk->sk_cgrp); 1145 1146 return atomic_long_read(prot->memory_allocated); 1147 } 1148 1149 static inline long 1150 sk_memory_allocated_add(struct sock *sk, int amt, int *parent_status) 1151 { 1152 struct proto *prot = sk->sk_prot; 1153 1154 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) { 1155 memcg_memory_allocated_add(sk->sk_cgrp, amt, parent_status); 1156 /* update the root cgroup regardless */ 1157 atomic_long_add_return(amt, prot->memory_allocated); 1158 return memcg_memory_allocated_read(sk->sk_cgrp); 1159 } 1160 1161 return atomic_long_add_return(amt, prot->memory_allocated); 1162 } 1163 1164 static inline void 1165 sk_memory_allocated_sub(struct sock *sk, int amt) 1166 { 1167 struct proto *prot = sk->sk_prot; 1168 1169 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) 1170 memcg_memory_allocated_sub(sk->sk_cgrp, amt); 1171 1172 atomic_long_sub(amt, prot->memory_allocated); 1173 } 1174 1175 static inline void sk_sockets_allocated_dec(struct sock *sk) 1176 { 1177 struct proto *prot = sk->sk_prot; 1178 1179 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) { 1180 struct cg_proto *cg_proto = sk->sk_cgrp; 1181 1182 for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto)) 1183 percpu_counter_dec(cg_proto->sockets_allocated); 1184 } 1185 1186 percpu_counter_dec(prot->sockets_allocated); 1187 } 1188 1189 static inline void sk_sockets_allocated_inc(struct sock *sk) 1190 { 1191 struct proto *prot = sk->sk_prot; 1192 1193 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) { 1194 struct cg_proto *cg_proto = sk->sk_cgrp; 1195 1196 for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto)) 1197 percpu_counter_inc(cg_proto->sockets_allocated); 1198 } 1199 1200 percpu_counter_inc(prot->sockets_allocated); 1201 } 1202 1203 static inline int 1204 sk_sockets_allocated_read_positive(struct sock *sk) 1205 { 1206 struct proto *prot = sk->sk_prot; 1207 1208 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) 1209 return percpu_counter_read_positive(sk->sk_cgrp->sockets_allocated); 1210 1211 return percpu_counter_read_positive(prot->sockets_allocated); 1212 } 1213 1214 static inline int 1215 proto_sockets_allocated_sum_positive(struct proto *prot) 1216 { 1217 return percpu_counter_sum_positive(prot->sockets_allocated); 1218 } 1219 1220 static inline long 1221 proto_memory_allocated(struct proto *prot) 1222 { 1223 return atomic_long_read(prot->memory_allocated); 1224 } 1225 1226 static inline bool 1227 proto_memory_pressure(struct proto *prot) 1228 { 1229 if (!prot->memory_pressure) 1230 return false; 1231 return !!*prot->memory_pressure; 1232 } 1233 1234 1235 #ifdef CONFIG_PROC_FS 1236 /* Called with local bh disabled */ 1237 extern void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc); 1238 extern int sock_prot_inuse_get(struct net *net, struct proto *proto); 1239 #else 1240 static inline void sock_prot_inuse_add(struct net *net, struct proto *prot, 1241 int inc) 1242 { 1243 } 1244 #endif 1245 1246 1247 /* With per-bucket locks this operation is not-atomic, so that 1248 * this version is not worse. 1249 */ 1250 static inline void __sk_prot_rehash(struct sock *sk) 1251 { 1252 sk->sk_prot->unhash(sk); 1253 sk->sk_prot->hash(sk); 1254 } 1255 1256 void sk_prot_clear_portaddr_nulls(struct sock *sk, int size); 1257 1258 /* About 10 seconds */ 1259 #define SOCK_DESTROY_TIME (10*HZ) 1260 1261 /* Sockets 0-1023 can't be bound to unless you are superuser */ 1262 #define PROT_SOCK 1024 1263 1264 #define SHUTDOWN_MASK 3 1265 #define RCV_SHUTDOWN 1 1266 #define SEND_SHUTDOWN 2 1267 1268 #define SOCK_SNDBUF_LOCK 1 1269 #define SOCK_RCVBUF_LOCK 2 1270 #define SOCK_BINDADDR_LOCK 4 1271 #define SOCK_BINDPORT_LOCK 8 1272 1273 /* sock_iocb: used to kick off async processing of socket ios */ 1274 struct sock_iocb { 1275 struct list_head list; 1276 1277 int flags; 1278 int size; 1279 struct socket *sock; 1280 struct sock *sk; 1281 struct scm_cookie *scm; 1282 struct msghdr *msg, async_msg; 1283 struct kiocb *kiocb; 1284 }; 1285 1286 static inline struct sock_iocb *kiocb_to_siocb(struct kiocb *iocb) 1287 { 1288 return (struct sock_iocb *)iocb->private; 1289 } 1290 1291 static inline struct kiocb *siocb_to_kiocb(struct sock_iocb *si) 1292 { 1293 return si->kiocb; 1294 } 1295 1296 struct socket_alloc { 1297 struct socket socket; 1298 struct inode vfs_inode; 1299 }; 1300 1301 static inline struct socket *SOCKET_I(struct inode *inode) 1302 { 1303 return &container_of(inode, struct socket_alloc, vfs_inode)->socket; 1304 } 1305 1306 static inline struct inode *SOCK_INODE(struct socket *socket) 1307 { 1308 return &container_of(socket, struct socket_alloc, socket)->vfs_inode; 1309 } 1310 1311 /* 1312 * Functions for memory accounting 1313 */ 1314 extern int __sk_mem_schedule(struct sock *sk, int size, int kind); 1315 extern void __sk_mem_reclaim(struct sock *sk); 1316 1317 #define SK_MEM_QUANTUM ((int)PAGE_SIZE) 1318 #define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM) 1319 #define SK_MEM_SEND 0 1320 #define SK_MEM_RECV 1 1321 1322 static inline int sk_mem_pages(int amt) 1323 { 1324 return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT; 1325 } 1326 1327 static inline bool sk_has_account(struct sock *sk) 1328 { 1329 /* return true if protocol supports memory accounting */ 1330 return !!sk->sk_prot->memory_allocated; 1331 } 1332 1333 static inline bool sk_wmem_schedule(struct sock *sk, int size) 1334 { 1335 if (!sk_has_account(sk)) 1336 return true; 1337 return size <= sk->sk_forward_alloc || 1338 __sk_mem_schedule(sk, size, SK_MEM_SEND); 1339 } 1340 1341 static inline bool 1342 sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size) 1343 { 1344 if (!sk_has_account(sk)) 1345 return true; 1346 return size<= sk->sk_forward_alloc || 1347 __sk_mem_schedule(sk, size, SK_MEM_RECV) || 1348 skb_pfmemalloc(skb); 1349 } 1350 1351 static inline void sk_mem_reclaim(struct sock *sk) 1352 { 1353 if (!sk_has_account(sk)) 1354 return; 1355 if (sk->sk_forward_alloc >= SK_MEM_QUANTUM) 1356 __sk_mem_reclaim(sk); 1357 } 1358 1359 static inline void sk_mem_reclaim_partial(struct sock *sk) 1360 { 1361 if (!sk_has_account(sk)) 1362 return; 1363 if (sk->sk_forward_alloc > SK_MEM_QUANTUM) 1364 __sk_mem_reclaim(sk); 1365 } 1366 1367 static inline void sk_mem_charge(struct sock *sk, int size) 1368 { 1369 if (!sk_has_account(sk)) 1370 return; 1371 sk->sk_forward_alloc -= size; 1372 } 1373 1374 static inline void sk_mem_uncharge(struct sock *sk, int size) 1375 { 1376 if (!sk_has_account(sk)) 1377 return; 1378 sk->sk_forward_alloc += size; 1379 } 1380 1381 static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb) 1382 { 1383 sock_set_flag(sk, SOCK_QUEUE_SHRUNK); 1384 sk->sk_wmem_queued -= skb->truesize; 1385 sk_mem_uncharge(sk, skb->truesize); 1386 __kfree_skb(skb); 1387 } 1388 1389 /* Used by processes to "lock" a socket state, so that 1390 * interrupts and bottom half handlers won't change it 1391 * from under us. It essentially blocks any incoming 1392 * packets, so that we won't get any new data or any 1393 * packets that change the state of the socket. 1394 * 1395 * While locked, BH processing will add new packets to 1396 * the backlog queue. This queue is processed by the 1397 * owner of the socket lock right before it is released. 1398 * 1399 * Since ~2.3.5 it is also exclusive sleep lock serializing 1400 * accesses from user process context. 1401 */ 1402 #define sock_owned_by_user(sk) ((sk)->sk_lock.owned) 1403 1404 /* 1405 * Macro so as to not evaluate some arguments when 1406 * lockdep is not enabled. 1407 * 1408 * Mark both the sk_lock and the sk_lock.slock as a 1409 * per-address-family lock class. 1410 */ 1411 #define sock_lock_init_class_and_name(sk, sname, skey, name, key) \ 1412 do { \ 1413 sk->sk_lock.owned = 0; \ 1414 init_waitqueue_head(&sk->sk_lock.wq); \ 1415 spin_lock_init(&(sk)->sk_lock.slock); \ 1416 debug_check_no_locks_freed((void *)&(sk)->sk_lock, \ 1417 sizeof((sk)->sk_lock)); \ 1418 lockdep_set_class_and_name(&(sk)->sk_lock.slock, \ 1419 (skey), (sname)); \ 1420 lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \ 1421 } while (0) 1422 1423 extern void lock_sock_nested(struct sock *sk, int subclass); 1424 1425 static inline void lock_sock(struct sock *sk) 1426 { 1427 lock_sock_nested(sk, 0); 1428 } 1429 1430 extern void release_sock(struct sock *sk); 1431 1432 /* BH context may only use the following locking interface. */ 1433 #define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock)) 1434 #define bh_lock_sock_nested(__sk) \ 1435 spin_lock_nested(&((__sk)->sk_lock.slock), \ 1436 SINGLE_DEPTH_NESTING) 1437 #define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock)) 1438 1439 extern bool lock_sock_fast(struct sock *sk); 1440 /** 1441 * unlock_sock_fast - complement of lock_sock_fast 1442 * @sk: socket 1443 * @slow: slow mode 1444 * 1445 * fast unlock socket for user context. 1446 * If slow mode is on, we call regular release_sock() 1447 */ 1448 static inline void unlock_sock_fast(struct sock *sk, bool slow) 1449 { 1450 if (slow) 1451 release_sock(sk); 1452 else 1453 spin_unlock_bh(&sk->sk_lock.slock); 1454 } 1455 1456 1457 extern struct sock *sk_alloc(struct net *net, int family, 1458 gfp_t priority, 1459 struct proto *prot); 1460 extern void sk_free(struct sock *sk); 1461 extern void sk_release_kernel(struct sock *sk); 1462 extern struct sock *sk_clone_lock(const struct sock *sk, 1463 const gfp_t priority); 1464 1465 extern struct sk_buff *sock_wmalloc(struct sock *sk, 1466 unsigned long size, int force, 1467 gfp_t priority); 1468 extern struct sk_buff *sock_rmalloc(struct sock *sk, 1469 unsigned long size, int force, 1470 gfp_t priority); 1471 extern void sock_wfree(struct sk_buff *skb); 1472 extern void sock_rfree(struct sk_buff *skb); 1473 extern void sock_edemux(struct sk_buff *skb); 1474 1475 extern int sock_setsockopt(struct socket *sock, int level, 1476 int op, char __user *optval, 1477 unsigned int optlen); 1478 1479 extern int sock_getsockopt(struct socket *sock, int level, 1480 int op, char __user *optval, 1481 int __user *optlen); 1482 extern struct sk_buff *sock_alloc_send_skb(struct sock *sk, 1483 unsigned long size, 1484 int noblock, 1485 int *errcode); 1486 extern struct sk_buff *sock_alloc_send_pskb(struct sock *sk, 1487 unsigned long header_len, 1488 unsigned long data_len, 1489 int noblock, 1490 int *errcode); 1491 extern void *sock_kmalloc(struct sock *sk, int size, 1492 gfp_t priority); 1493 extern void sock_kfree_s(struct sock *sk, void *mem, int size); 1494 extern void sk_send_sigurg(struct sock *sk); 1495 1496 /* 1497 * Functions to fill in entries in struct proto_ops when a protocol 1498 * does not implement a particular function. 1499 */ 1500 extern int sock_no_bind(struct socket *, 1501 struct sockaddr *, int); 1502 extern int sock_no_connect(struct socket *, 1503 struct sockaddr *, int, int); 1504 extern int sock_no_socketpair(struct socket *, 1505 struct socket *); 1506 extern int sock_no_accept(struct socket *, 1507 struct socket *, int); 1508 extern int sock_no_getname(struct socket *, 1509 struct sockaddr *, int *, int); 1510 extern unsigned int sock_no_poll(struct file *, struct socket *, 1511 struct poll_table_struct *); 1512 extern int sock_no_ioctl(struct socket *, unsigned int, 1513 unsigned long); 1514 extern int sock_no_listen(struct socket *, int); 1515 extern int sock_no_shutdown(struct socket *, int); 1516 extern int sock_no_getsockopt(struct socket *, int , int, 1517 char __user *, int __user *); 1518 extern int sock_no_setsockopt(struct socket *, int, int, 1519 char __user *, unsigned int); 1520 extern int sock_no_sendmsg(struct kiocb *, struct socket *, 1521 struct msghdr *, size_t); 1522 extern int sock_no_recvmsg(struct kiocb *, struct socket *, 1523 struct msghdr *, size_t, int); 1524 extern int sock_no_mmap(struct file *file, 1525 struct socket *sock, 1526 struct vm_area_struct *vma); 1527 extern ssize_t sock_no_sendpage(struct socket *sock, 1528 struct page *page, 1529 int offset, size_t size, 1530 int flags); 1531 1532 /* 1533 * Functions to fill in entries in struct proto_ops when a protocol 1534 * uses the inet style. 1535 */ 1536 extern int sock_common_getsockopt(struct socket *sock, int level, int optname, 1537 char __user *optval, int __user *optlen); 1538 extern int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock, 1539 struct msghdr *msg, size_t size, int flags); 1540 extern int sock_common_setsockopt(struct socket *sock, int level, int optname, 1541 char __user *optval, unsigned int optlen); 1542 extern int compat_sock_common_getsockopt(struct socket *sock, int level, 1543 int optname, char __user *optval, int __user *optlen); 1544 extern int compat_sock_common_setsockopt(struct socket *sock, int level, 1545 int optname, char __user *optval, unsigned int optlen); 1546 1547 extern void sk_common_release(struct sock *sk); 1548 1549 /* 1550 * Default socket callbacks and setup code 1551 */ 1552 1553 /* Initialise core socket variables */ 1554 extern void sock_init_data(struct socket *sock, struct sock *sk); 1555 1556 extern void sk_filter_release_rcu(struct rcu_head *rcu); 1557 1558 /** 1559 * sk_filter_release - release a socket filter 1560 * @fp: filter to remove 1561 * 1562 * Remove a filter from a socket and release its resources. 1563 */ 1564 1565 static inline void sk_filter_release(struct sk_filter *fp) 1566 { 1567 if (atomic_dec_and_test(&fp->refcnt)) 1568 call_rcu(&fp->rcu, sk_filter_release_rcu); 1569 } 1570 1571 static inline void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp) 1572 { 1573 unsigned int size = sk_filter_len(fp); 1574 1575 atomic_sub(size, &sk->sk_omem_alloc); 1576 sk_filter_release(fp); 1577 } 1578 1579 static inline void sk_filter_charge(struct sock *sk, struct sk_filter *fp) 1580 { 1581 atomic_inc(&fp->refcnt); 1582 atomic_add(sk_filter_len(fp), &sk->sk_omem_alloc); 1583 } 1584 1585 /* 1586 * Socket reference counting postulates. 1587 * 1588 * * Each user of socket SHOULD hold a reference count. 1589 * * Each access point to socket (an hash table bucket, reference from a list, 1590 * running timer, skb in flight MUST hold a reference count. 1591 * * When reference count hits 0, it means it will never increase back. 1592 * * When reference count hits 0, it means that no references from 1593 * outside exist to this socket and current process on current CPU 1594 * is last user and may/should destroy this socket. 1595 * * sk_free is called from any context: process, BH, IRQ. When 1596 * it is called, socket has no references from outside -> sk_free 1597 * may release descendant resources allocated by the socket, but 1598 * to the time when it is called, socket is NOT referenced by any 1599 * hash tables, lists etc. 1600 * * Packets, delivered from outside (from network or from another process) 1601 * and enqueued on receive/error queues SHOULD NOT grab reference count, 1602 * when they sit in queue. Otherwise, packets will leak to hole, when 1603 * socket is looked up by one cpu and unhasing is made by another CPU. 1604 * It is true for udp/raw, netlink (leak to receive and error queues), tcp 1605 * (leak to backlog). Packet socket does all the processing inside 1606 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets 1607 * use separate SMP lock, so that they are prone too. 1608 */ 1609 1610 /* Ungrab socket and destroy it, if it was the last reference. */ 1611 static inline void sock_put(struct sock *sk) 1612 { 1613 if (atomic_dec_and_test(&sk->sk_refcnt)) 1614 sk_free(sk); 1615 } 1616 1617 extern int sk_receive_skb(struct sock *sk, struct sk_buff *skb, 1618 const int nested); 1619 1620 static inline void sk_tx_queue_set(struct sock *sk, int tx_queue) 1621 { 1622 sk->sk_tx_queue_mapping = tx_queue; 1623 } 1624 1625 static inline void sk_tx_queue_clear(struct sock *sk) 1626 { 1627 sk->sk_tx_queue_mapping = -1; 1628 } 1629 1630 static inline int sk_tx_queue_get(const struct sock *sk) 1631 { 1632 return sk ? sk->sk_tx_queue_mapping : -1; 1633 } 1634 1635 static inline void sk_set_socket(struct sock *sk, struct socket *sock) 1636 { 1637 sk_tx_queue_clear(sk); 1638 sk->sk_socket = sock; 1639 } 1640 1641 static inline wait_queue_head_t *sk_sleep(struct sock *sk) 1642 { 1643 BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0); 1644 return &rcu_dereference_raw(sk->sk_wq)->wait; 1645 } 1646 /* Detach socket from process context. 1647 * Announce socket dead, detach it from wait queue and inode. 1648 * Note that parent inode held reference count on this struct sock, 1649 * we do not release it in this function, because protocol 1650 * probably wants some additional cleanups or even continuing 1651 * to work with this socket (TCP). 1652 */ 1653 static inline void sock_orphan(struct sock *sk) 1654 { 1655 write_lock_bh(&sk->sk_callback_lock); 1656 sock_set_flag(sk, SOCK_DEAD); 1657 sk_set_socket(sk, NULL); 1658 sk->sk_wq = NULL; 1659 write_unlock_bh(&sk->sk_callback_lock); 1660 } 1661 1662 static inline void sock_graft(struct sock *sk, struct socket *parent) 1663 { 1664 write_lock_bh(&sk->sk_callback_lock); 1665 sk->sk_wq = parent->wq; 1666 parent->sk = sk; 1667 sk_set_socket(sk, parent); 1668 security_sock_graft(sk, parent); 1669 write_unlock_bh(&sk->sk_callback_lock); 1670 } 1671 1672 extern kuid_t sock_i_uid(struct sock *sk); 1673 extern unsigned long sock_i_ino(struct sock *sk); 1674 1675 static inline struct dst_entry * 1676 __sk_dst_get(struct sock *sk) 1677 { 1678 return rcu_dereference_check(sk->sk_dst_cache, sock_owned_by_user(sk) || 1679 lockdep_is_held(&sk->sk_lock.slock)); 1680 } 1681 1682 static inline struct dst_entry * 1683 sk_dst_get(struct sock *sk) 1684 { 1685 struct dst_entry *dst; 1686 1687 rcu_read_lock(); 1688 dst = rcu_dereference(sk->sk_dst_cache); 1689 if (dst) 1690 dst_hold(dst); 1691 rcu_read_unlock(); 1692 return dst; 1693 } 1694 1695 extern void sk_reset_txq(struct sock *sk); 1696 1697 static inline void dst_negative_advice(struct sock *sk) 1698 { 1699 struct dst_entry *ndst, *dst = __sk_dst_get(sk); 1700 1701 if (dst && dst->ops->negative_advice) { 1702 ndst = dst->ops->negative_advice(dst); 1703 1704 if (ndst != dst) { 1705 rcu_assign_pointer(sk->sk_dst_cache, ndst); 1706 sk_reset_txq(sk); 1707 } 1708 } 1709 } 1710 1711 static inline void 1712 __sk_dst_set(struct sock *sk, struct dst_entry *dst) 1713 { 1714 struct dst_entry *old_dst; 1715 1716 sk_tx_queue_clear(sk); 1717 /* 1718 * This can be called while sk is owned by the caller only, 1719 * with no state that can be checked in a rcu_dereference_check() cond 1720 */ 1721 old_dst = rcu_dereference_raw(sk->sk_dst_cache); 1722 rcu_assign_pointer(sk->sk_dst_cache, dst); 1723 dst_release(old_dst); 1724 } 1725 1726 static inline void 1727 sk_dst_set(struct sock *sk, struct dst_entry *dst) 1728 { 1729 spin_lock(&sk->sk_dst_lock); 1730 __sk_dst_set(sk, dst); 1731 spin_unlock(&sk->sk_dst_lock); 1732 } 1733 1734 static inline void 1735 __sk_dst_reset(struct sock *sk) 1736 { 1737 __sk_dst_set(sk, NULL); 1738 } 1739 1740 static inline void 1741 sk_dst_reset(struct sock *sk) 1742 { 1743 spin_lock(&sk->sk_dst_lock); 1744 __sk_dst_reset(sk); 1745 spin_unlock(&sk->sk_dst_lock); 1746 } 1747 1748 extern struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie); 1749 1750 extern struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie); 1751 1752 static inline bool sk_can_gso(const struct sock *sk) 1753 { 1754 return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type); 1755 } 1756 1757 extern void sk_setup_caps(struct sock *sk, struct dst_entry *dst); 1758 1759 static inline void sk_nocaps_add(struct sock *sk, netdev_features_t flags) 1760 { 1761 sk->sk_route_nocaps |= flags; 1762 sk->sk_route_caps &= ~flags; 1763 } 1764 1765 static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb, 1766 char __user *from, char *to, 1767 int copy, int offset) 1768 { 1769 if (skb->ip_summed == CHECKSUM_NONE) { 1770 int err = 0; 1771 __wsum csum = csum_and_copy_from_user(from, to, copy, 0, &err); 1772 if (err) 1773 return err; 1774 skb->csum = csum_block_add(skb->csum, csum, offset); 1775 } else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) { 1776 if (!access_ok(VERIFY_READ, from, copy) || 1777 __copy_from_user_nocache(to, from, copy)) 1778 return -EFAULT; 1779 } else if (copy_from_user(to, from, copy)) 1780 return -EFAULT; 1781 1782 return 0; 1783 } 1784 1785 static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb, 1786 char __user *from, int copy) 1787 { 1788 int err, offset = skb->len; 1789 1790 err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy), 1791 copy, offset); 1792 if (err) 1793 __skb_trim(skb, offset); 1794 1795 return err; 1796 } 1797 1798 static inline int skb_copy_to_page_nocache(struct sock *sk, char __user *from, 1799 struct sk_buff *skb, 1800 struct page *page, 1801 int off, int copy) 1802 { 1803 int err; 1804 1805 err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off, 1806 copy, skb->len); 1807 if (err) 1808 return err; 1809 1810 skb->len += copy; 1811 skb->data_len += copy; 1812 skb->truesize += copy; 1813 sk->sk_wmem_queued += copy; 1814 sk_mem_charge(sk, copy); 1815 return 0; 1816 } 1817 1818 static inline int skb_copy_to_page(struct sock *sk, char __user *from, 1819 struct sk_buff *skb, struct page *page, 1820 int off, int copy) 1821 { 1822 if (skb->ip_summed == CHECKSUM_NONE) { 1823 int err = 0; 1824 __wsum csum = csum_and_copy_from_user(from, 1825 page_address(page) + off, 1826 copy, 0, &err); 1827 if (err) 1828 return err; 1829 skb->csum = csum_block_add(skb->csum, csum, skb->len); 1830 } else if (copy_from_user(page_address(page) + off, from, copy)) 1831 return -EFAULT; 1832 1833 skb->len += copy; 1834 skb->data_len += copy; 1835 skb->truesize += copy; 1836 sk->sk_wmem_queued += copy; 1837 sk_mem_charge(sk, copy); 1838 return 0; 1839 } 1840 1841 /** 1842 * sk_wmem_alloc_get - returns write allocations 1843 * @sk: socket 1844 * 1845 * Returns sk_wmem_alloc minus initial offset of one 1846 */ 1847 static inline int sk_wmem_alloc_get(const struct sock *sk) 1848 { 1849 return atomic_read(&sk->sk_wmem_alloc) - 1; 1850 } 1851 1852 /** 1853 * sk_rmem_alloc_get - returns read allocations 1854 * @sk: socket 1855 * 1856 * Returns sk_rmem_alloc 1857 */ 1858 static inline int sk_rmem_alloc_get(const struct sock *sk) 1859 { 1860 return atomic_read(&sk->sk_rmem_alloc); 1861 } 1862 1863 /** 1864 * sk_has_allocations - check if allocations are outstanding 1865 * @sk: socket 1866 * 1867 * Returns true if socket has write or read allocations 1868 */ 1869 static inline bool sk_has_allocations(const struct sock *sk) 1870 { 1871 return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk); 1872 } 1873 1874 /** 1875 * wq_has_sleeper - check if there are any waiting processes 1876 * @wq: struct socket_wq 1877 * 1878 * Returns true if socket_wq has waiting processes 1879 * 1880 * The purpose of the wq_has_sleeper and sock_poll_wait is to wrap the memory 1881 * barrier call. They were added due to the race found within the tcp code. 1882 * 1883 * Consider following tcp code paths: 1884 * 1885 * CPU1 CPU2 1886 * 1887 * sys_select receive packet 1888 * ... ... 1889 * __add_wait_queue update tp->rcv_nxt 1890 * ... ... 1891 * tp->rcv_nxt check sock_def_readable 1892 * ... { 1893 * schedule rcu_read_lock(); 1894 * wq = rcu_dereference(sk->sk_wq); 1895 * if (wq && waitqueue_active(&wq->wait)) 1896 * wake_up_interruptible(&wq->wait) 1897 * ... 1898 * } 1899 * 1900 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay 1901 * in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1 1902 * could then endup calling schedule and sleep forever if there are no more 1903 * data on the socket. 1904 * 1905 */ 1906 static inline bool wq_has_sleeper(struct socket_wq *wq) 1907 { 1908 /* We need to be sure we are in sync with the 1909 * add_wait_queue modifications to the wait queue. 1910 * 1911 * This memory barrier is paired in the sock_poll_wait. 1912 */ 1913 smp_mb(); 1914 return wq && waitqueue_active(&wq->wait); 1915 } 1916 1917 /** 1918 * sock_poll_wait - place memory barrier behind the poll_wait call. 1919 * @filp: file 1920 * @wait_address: socket wait queue 1921 * @p: poll_table 1922 * 1923 * See the comments in the wq_has_sleeper function. 1924 */ 1925 static inline void sock_poll_wait(struct file *filp, 1926 wait_queue_head_t *wait_address, poll_table *p) 1927 { 1928 if (!poll_does_not_wait(p) && wait_address) { 1929 poll_wait(filp, wait_address, p); 1930 /* We need to be sure we are in sync with the 1931 * socket flags modification. 1932 * 1933 * This memory barrier is paired in the wq_has_sleeper. 1934 */ 1935 smp_mb(); 1936 } 1937 } 1938 1939 /* 1940 * Queue a received datagram if it will fit. Stream and sequenced 1941 * protocols can't normally use this as they need to fit buffers in 1942 * and play with them. 1943 * 1944 * Inlined as it's very short and called for pretty much every 1945 * packet ever received. 1946 */ 1947 1948 static inline void skb_set_owner_w(struct sk_buff *skb, struct sock *sk) 1949 { 1950 skb_orphan(skb); 1951 skb->sk = sk; 1952 skb->destructor = sock_wfree; 1953 /* 1954 * We used to take a refcount on sk, but following operation 1955 * is enough to guarantee sk_free() wont free this sock until 1956 * all in-flight packets are completed 1957 */ 1958 atomic_add(skb->truesize, &sk->sk_wmem_alloc); 1959 } 1960 1961 static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk) 1962 { 1963 skb_orphan(skb); 1964 skb->sk = sk; 1965 skb->destructor = sock_rfree; 1966 atomic_add(skb->truesize, &sk->sk_rmem_alloc); 1967 sk_mem_charge(sk, skb->truesize); 1968 } 1969 1970 extern void sk_reset_timer(struct sock *sk, struct timer_list *timer, 1971 unsigned long expires); 1972 1973 extern void sk_stop_timer(struct sock *sk, struct timer_list *timer); 1974 1975 extern int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb); 1976 1977 extern int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb); 1978 1979 /* 1980 * Recover an error report and clear atomically 1981 */ 1982 1983 static inline int sock_error(struct sock *sk) 1984 { 1985 int err; 1986 if (likely(!sk->sk_err)) 1987 return 0; 1988 err = xchg(&sk->sk_err, 0); 1989 return -err; 1990 } 1991 1992 static inline unsigned long sock_wspace(struct sock *sk) 1993 { 1994 int amt = 0; 1995 1996 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) { 1997 amt = sk->sk_sndbuf - atomic_read(&sk->sk_wmem_alloc); 1998 if (amt < 0) 1999 amt = 0; 2000 } 2001 return amt; 2002 } 2003 2004 static inline void sk_wake_async(struct sock *sk, int how, int band) 2005 { 2006 if (sock_flag(sk, SOCK_FASYNC)) 2007 sock_wake_async(sk->sk_socket, how, band); 2008 } 2009 2010 #define SOCK_MIN_SNDBUF 2048 2011 /* 2012 * Since sk_rmem_alloc sums skb->truesize, even a small frame might need 2013 * sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak 2014 */ 2015 #define SOCK_MIN_RCVBUF (2048 + sizeof(struct sk_buff)) 2016 2017 static inline void sk_stream_moderate_sndbuf(struct sock *sk) 2018 { 2019 if (!(sk->sk_userlocks & SOCK_SNDBUF_LOCK)) { 2020 sk->sk_sndbuf = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1); 2021 sk->sk_sndbuf = max(sk->sk_sndbuf, SOCK_MIN_SNDBUF); 2022 } 2023 } 2024 2025 struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp); 2026 2027 /** 2028 * sk_page_frag - return an appropriate page_frag 2029 * @sk: socket 2030 * 2031 * If socket allocation mode allows current thread to sleep, it means its 2032 * safe to use the per task page_frag instead of the per socket one. 2033 */ 2034 static inline struct page_frag *sk_page_frag(struct sock *sk) 2035 { 2036 if (sk->sk_allocation & __GFP_WAIT) 2037 return ¤t->task_frag; 2038 2039 return &sk->sk_frag; 2040 } 2041 2042 extern bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag); 2043 2044 /* 2045 * Default write policy as shown to user space via poll/select/SIGIO 2046 */ 2047 static inline bool sock_writeable(const struct sock *sk) 2048 { 2049 return atomic_read(&sk->sk_wmem_alloc) < (sk->sk_sndbuf >> 1); 2050 } 2051 2052 static inline gfp_t gfp_any(void) 2053 { 2054 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL; 2055 } 2056 2057 static inline long sock_rcvtimeo(const struct sock *sk, bool noblock) 2058 { 2059 return noblock ? 0 : sk->sk_rcvtimeo; 2060 } 2061 2062 static inline long sock_sndtimeo(const struct sock *sk, bool noblock) 2063 { 2064 return noblock ? 0 : sk->sk_sndtimeo; 2065 } 2066 2067 static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len) 2068 { 2069 return (waitall ? len : min_t(int, sk->sk_rcvlowat, len)) ? : 1; 2070 } 2071 2072 /* Alas, with timeout socket operations are not restartable. 2073 * Compare this to poll(). 2074 */ 2075 static inline int sock_intr_errno(long timeo) 2076 { 2077 return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR; 2078 } 2079 2080 extern void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk, 2081 struct sk_buff *skb); 2082 extern void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk, 2083 struct sk_buff *skb); 2084 2085 static inline void 2086 sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb) 2087 { 2088 ktime_t kt = skb->tstamp; 2089 struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb); 2090 2091 /* 2092 * generate control messages if 2093 * - receive time stamping in software requested (SOCK_RCVTSTAMP 2094 * or SOCK_TIMESTAMPING_RX_SOFTWARE) 2095 * - software time stamp available and wanted 2096 * (SOCK_TIMESTAMPING_SOFTWARE) 2097 * - hardware time stamps available and wanted 2098 * (SOCK_TIMESTAMPING_SYS_HARDWARE or 2099 * SOCK_TIMESTAMPING_RAW_HARDWARE) 2100 */ 2101 if (sock_flag(sk, SOCK_RCVTSTAMP) || 2102 sock_flag(sk, SOCK_TIMESTAMPING_RX_SOFTWARE) || 2103 (kt.tv64 && sock_flag(sk, SOCK_TIMESTAMPING_SOFTWARE)) || 2104 (hwtstamps->hwtstamp.tv64 && 2105 sock_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE)) || 2106 (hwtstamps->syststamp.tv64 && 2107 sock_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE))) 2108 __sock_recv_timestamp(msg, sk, skb); 2109 else 2110 sk->sk_stamp = kt; 2111 2112 if (sock_flag(sk, SOCK_WIFI_STATUS) && skb->wifi_acked_valid) 2113 __sock_recv_wifi_status(msg, sk, skb); 2114 } 2115 2116 extern void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk, 2117 struct sk_buff *skb); 2118 2119 static inline void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk, 2120 struct sk_buff *skb) 2121 { 2122 #define FLAGS_TS_OR_DROPS ((1UL << SOCK_RXQ_OVFL) | \ 2123 (1UL << SOCK_RCVTSTAMP) | \ 2124 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE) | \ 2125 (1UL << SOCK_TIMESTAMPING_SOFTWARE) | \ 2126 (1UL << SOCK_TIMESTAMPING_RAW_HARDWARE) | \ 2127 (1UL << SOCK_TIMESTAMPING_SYS_HARDWARE)) 2128 2129 if (sk->sk_flags & FLAGS_TS_OR_DROPS) 2130 __sock_recv_ts_and_drops(msg, sk, skb); 2131 else 2132 sk->sk_stamp = skb->tstamp; 2133 } 2134 2135 /** 2136 * sock_tx_timestamp - checks whether the outgoing packet is to be time stamped 2137 * @sk: socket sending this packet 2138 * @tx_flags: filled with instructions for time stamping 2139 * 2140 * Currently only depends on SOCK_TIMESTAMPING* flags. Returns error code if 2141 * parameters are invalid. 2142 */ 2143 extern int sock_tx_timestamp(struct sock *sk, __u8 *tx_flags); 2144 2145 /** 2146 * sk_eat_skb - Release a skb if it is no longer needed 2147 * @sk: socket to eat this skb from 2148 * @skb: socket buffer to eat 2149 * @copied_early: flag indicating whether DMA operations copied this data early 2150 * 2151 * This routine must be called with interrupts disabled or with the socket 2152 * locked so that the sk_buff queue operation is ok. 2153 */ 2154 #ifdef CONFIG_NET_DMA 2155 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb, bool copied_early) 2156 { 2157 __skb_unlink(skb, &sk->sk_receive_queue); 2158 if (!copied_early) 2159 __kfree_skb(skb); 2160 else 2161 __skb_queue_tail(&sk->sk_async_wait_queue, skb); 2162 } 2163 #else 2164 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb, bool copied_early) 2165 { 2166 __skb_unlink(skb, &sk->sk_receive_queue); 2167 __kfree_skb(skb); 2168 } 2169 #endif 2170 2171 static inline 2172 struct net *sock_net(const struct sock *sk) 2173 { 2174 return read_pnet(&sk->sk_net); 2175 } 2176 2177 static inline 2178 void sock_net_set(struct sock *sk, struct net *net) 2179 { 2180 write_pnet(&sk->sk_net, net); 2181 } 2182 2183 /* 2184 * Kernel sockets, f.e. rtnl or icmp_socket, are a part of a namespace. 2185 * They should not hold a reference to a namespace in order to allow 2186 * to stop it. 2187 * Sockets after sk_change_net should be released using sk_release_kernel 2188 */ 2189 static inline void sk_change_net(struct sock *sk, struct net *net) 2190 { 2191 put_net(sock_net(sk)); 2192 sock_net_set(sk, hold_net(net)); 2193 } 2194 2195 static inline struct sock *skb_steal_sock(struct sk_buff *skb) 2196 { 2197 if (skb->sk) { 2198 struct sock *sk = skb->sk; 2199 2200 skb->destructor = NULL; 2201 skb->sk = NULL; 2202 return sk; 2203 } 2204 return NULL; 2205 } 2206 2207 extern void sock_enable_timestamp(struct sock *sk, int flag); 2208 extern int sock_get_timestamp(struct sock *, struct timeval __user *); 2209 extern int sock_get_timestampns(struct sock *, struct timespec __user *); 2210 2211 /* 2212 * Enable debug/info messages 2213 */ 2214 extern int net_msg_warn; 2215 #define NETDEBUG(fmt, args...) \ 2216 do { if (net_msg_warn) printk(fmt,##args); } while (0) 2217 2218 #define LIMIT_NETDEBUG(fmt, args...) \ 2219 do { if (net_msg_warn && net_ratelimit()) printk(fmt,##args); } while(0) 2220 2221 extern __u32 sysctl_wmem_max; 2222 extern __u32 sysctl_rmem_max; 2223 2224 extern int sysctl_optmem_max; 2225 2226 extern __u32 sysctl_wmem_default; 2227 extern __u32 sysctl_rmem_default; 2228 2229 #endif /* _SOCK_H */ 2230