1 /* SPDX-License-Identifier: GPL-2.0-or-later */
3 * INET An implementation of the TCP/IP protocol suite for the LINUX
4 * operating system. INET is implemented using the BSD Socket
5 * interface as the means of communication with the user level.
7 * Definitions for the AF_INET socket handler.
9 * Version: @(#)sock.h 1.0.4 05/13/93
12 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
13 * Corey Minyard <wf-rch!minyard@relay.EU.net>
14 * Florian La Roche <flla@stud.uni-sb.de>
17 * Alan Cox : Volatiles in skbuff pointers. See
18 * skbuff comments. May be overdone,
19 * better to prove they can be removed
21 * Alan Cox : Added a zapped field for tcp to note
22 * a socket is reset and must stay shut up
23 * Alan Cox : New fields for options
24 * Pauline Middelink : identd support
25 * Alan Cox : Eliminate low level recv/recvfrom
26 * David S. Miller : New socket lookup architecture.
27 * Steve Whitehouse: Default routines for sock_ops
28 * Arnaldo C. Melo : removed net_pinfo, tp_pinfo and made
29 * protinfo be just a void pointer, as the
30 * protocol specific parts were moved to
31 * respective headers and ipv4/v6, etc now
32 * use private slabcaches for its socks
33 * Pedro Hortas : New flags field for socket options
38 #include <linux/hardirq.h>
39 #include <linux/kernel.h>
40 #include <linux/list.h>
41 #include <linux/list_nulls.h>
42 #include <linux/timer.h>
43 #include <linux/cache.h>
44 #include <linux/bitops.h>
45 #include <linux/lockdep.h>
46 #include <linux/netdevice.h>
47 #include <linux/skbuff.h> /* struct sk_buff */
49 #include <linux/security.h>
50 #include <linux/slab.h>
51 #include <linux/uaccess.h>
52 #include <linux/page_counter.h>
53 #include <linux/memcontrol.h>
54 #include <linux/static_key.h>
55 #include <linux/sched.h>
56 #include <linux/wait.h>
57 #include <linux/cgroup-defs.h>
58 #include <linux/rbtree.h>
59 #include <linux/filter.h>
60 #include <linux/rculist_nulls.h>
61 #include <linux/poll.h>
62 #include <linux/sockptr.h>
63 #include <linux/indirect_call_wrapper.h>
64 #include <linux/atomic.h>
65 #include <linux/refcount.h>
67 #include <net/checksum.h>
68 #include <net/tcp_states.h>
69 #include <linux/net_tstamp.h>
70 #include <net/l3mdev.h>
73 * This structure really needs to be cleaned up.
74 * Most of it is for TCP, and not used by any of
75 * the other protocols.
78 /* Define this to get the SOCK_DBG debugging facility. */
79 #define SOCK_DEBUGGING
81 #define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \
82 printk(KERN_DEBUG msg); } while (0)
84 /* Validate arguments and do nothing */
85 static inline __printf(2, 3)
86 void SOCK_DEBUG(const struct sock *sk, const char *msg, ...)
91 /* This is the per-socket lock. The spinlock provides a synchronization
92 * between user contexts and software interrupt processing, whereas the
93 * mini-semaphore synchronizes multiple users amongst themselves.
100 * We express the mutex-alike socket_lock semantics
101 * to the lock validator by explicitly managing
102 * the slock as a lock variant (in addition to
105 #ifdef CONFIG_DEBUG_LOCK_ALLOC
106 struct lockdep_map dep_map;
114 typedef __u32 __bitwise __portpair;
115 typedef __u64 __bitwise __addrpair;
118 * struct sock_common - minimal network layer representation of sockets
119 * @skc_daddr: Foreign IPv4 addr
120 * @skc_rcv_saddr: Bound local IPv4 addr
121 * @skc_addrpair: 8-byte-aligned __u64 union of @skc_daddr & @skc_rcv_saddr
122 * @skc_hash: hash value used with various protocol lookup tables
123 * @skc_u16hashes: two u16 hash values used by UDP lookup tables
124 * @skc_dport: placeholder for inet_dport/tw_dport
125 * @skc_num: placeholder for inet_num/tw_num
126 * @skc_portpair: __u32 union of @skc_dport & @skc_num
127 * @skc_family: network address family
128 * @skc_state: Connection state
129 * @skc_reuse: %SO_REUSEADDR setting
130 * @skc_reuseport: %SO_REUSEPORT setting
131 * @skc_ipv6only: socket is IPV6 only
132 * @skc_net_refcnt: socket is using net ref counting
133 * @skc_bound_dev_if: bound device index if != 0
134 * @skc_bind_node: bind hash linkage for various protocol lookup tables
135 * @skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol
136 * @skc_prot: protocol handlers inside a network family
137 * @skc_net: reference to the network namespace of this socket
138 * @skc_v6_daddr: IPV6 destination address
139 * @skc_v6_rcv_saddr: IPV6 source address
140 * @skc_cookie: socket's cookie value
141 * @skc_node: main hash linkage for various protocol lookup tables
142 * @skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol
143 * @skc_tx_queue_mapping: tx queue number for this connection
144 * @skc_rx_queue_mapping: rx queue number for this connection
145 * @skc_flags: place holder for sk_flags
146 * %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE,
147 * %SO_OOBINLINE settings, %SO_TIMESTAMPING settings
148 * @skc_listener: connection request listener socket (aka rsk_listener)
149 * [union with @skc_flags]
150 * @skc_tw_dr: (aka tw_dr) ptr to &struct inet_timewait_death_row
151 * [union with @skc_flags]
152 * @skc_incoming_cpu: record/match cpu processing incoming packets
153 * @skc_rcv_wnd: (aka rsk_rcv_wnd) TCP receive window size (possibly scaled)
154 * [union with @skc_incoming_cpu]
155 * @skc_tw_rcv_nxt: (aka tw_rcv_nxt) TCP window next expected seq number
156 * [union with @skc_incoming_cpu]
157 * @skc_refcnt: reference count
159 * This is the minimal network layer representation of sockets, the header
160 * for struct sock and struct inet_timewait_sock.
163 /* skc_daddr and skc_rcv_saddr must be grouped on a 8 bytes aligned
164 * address on 64bit arches : cf INET_MATCH()
167 __addrpair skc_addrpair;
170 __be32 skc_rcv_saddr;
174 unsigned int skc_hash;
175 __u16 skc_u16hashes[2];
177 /* skc_dport && skc_num must be grouped as well */
179 __portpair skc_portpair;
186 unsigned short skc_family;
187 volatile unsigned char skc_state;
188 unsigned char skc_reuse:4;
189 unsigned char skc_reuseport:1;
190 unsigned char skc_ipv6only:1;
191 unsigned char skc_net_refcnt:1;
192 int skc_bound_dev_if;
194 struct hlist_node skc_bind_node;
195 struct hlist_node skc_portaddr_node;
197 struct proto *skc_prot;
198 possible_net_t skc_net;
200 #if IS_ENABLED(CONFIG_IPV6)
201 struct in6_addr skc_v6_daddr;
202 struct in6_addr skc_v6_rcv_saddr;
205 atomic64_t skc_cookie;
207 /* following fields are padding to force
208 * offset(struct sock, sk_refcnt) == 128 on 64bit arches
209 * assuming IPV6 is enabled. We use this padding differently
210 * for different kind of 'sockets'
213 unsigned long skc_flags;
214 struct sock *skc_listener; /* request_sock */
215 struct inet_timewait_death_row *skc_tw_dr; /* inet_timewait_sock */
218 * fields between dontcopy_begin/dontcopy_end
219 * are not copied in sock_copy()
222 int skc_dontcopy_begin[0];
225 struct hlist_node skc_node;
226 struct hlist_nulls_node skc_nulls_node;
228 unsigned short skc_tx_queue_mapping;
229 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
230 unsigned short skc_rx_queue_mapping;
233 int skc_incoming_cpu;
235 u32 skc_tw_rcv_nxt; /* struct tcp_timewait_sock */
238 refcount_t skc_refcnt;
240 int skc_dontcopy_end[0];
243 u32 skc_window_clamp;
244 u32 skc_tw_snd_nxt; /* struct tcp_timewait_sock */
249 struct bpf_local_storage;
252 * struct sock - network layer representation of sockets
253 * @__sk_common: shared layout with inet_timewait_sock
254 * @sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
255 * @sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
256 * @sk_lock: synchronizer
257 * @sk_kern_sock: True if sock is using kernel lock classes
258 * @sk_rcvbuf: size of receive buffer in bytes
259 * @sk_wq: sock wait queue and async head
260 * @sk_rx_dst: receive input route used by early demux
261 * @sk_dst_cache: destination cache
262 * @sk_dst_pending_confirm: need to confirm neighbour
263 * @sk_policy: flow policy
264 * @sk_rx_skb_cache: cache copy of recently accessed RX skb
265 * @sk_receive_queue: incoming packets
266 * @sk_wmem_alloc: transmit queue bytes committed
267 * @sk_tsq_flags: TCP Small Queues flags
268 * @sk_write_queue: Packet sending queue
269 * @sk_omem_alloc: "o" is "option" or "other"
270 * @sk_wmem_queued: persistent queue size
271 * @sk_forward_alloc: space allocated forward
272 * @sk_napi_id: id of the last napi context to receive data for sk
273 * @sk_ll_usec: usecs to busypoll when there is no data
274 * @sk_allocation: allocation mode
275 * @sk_pacing_rate: Pacing rate (if supported by transport/packet scheduler)
276 * @sk_pacing_status: Pacing status (requested, handled by sch_fq)
277 * @sk_max_pacing_rate: Maximum pacing rate (%SO_MAX_PACING_RATE)
278 * @sk_sndbuf: size of send buffer in bytes
279 * @__sk_flags_offset: empty field used to determine location of bitfield
280 * @sk_padding: unused element for alignment
281 * @sk_no_check_tx: %SO_NO_CHECK setting, set checksum in TX packets
282 * @sk_no_check_rx: allow zero checksum in RX packets
283 * @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
284 * @sk_route_nocaps: forbidden route capabilities (e.g NETIF_F_GSO_MASK)
285 * @sk_route_forced_caps: static, forced route capabilities
286 * (set in tcp_init_sock())
287 * @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
288 * @sk_gso_max_size: Maximum GSO segment size to build
289 * @sk_gso_max_segs: Maximum number of GSO segments
290 * @sk_pacing_shift: scaling factor for TCP Small Queues
291 * @sk_lingertime: %SO_LINGER l_linger setting
292 * @sk_backlog: always used with the per-socket spinlock held
293 * @sk_callback_lock: used with the callbacks in the end of this struct
294 * @sk_error_queue: rarely used
295 * @sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt,
296 * IPV6_ADDRFORM for instance)
297 * @sk_err: last error
298 * @sk_err_soft: errors that don't cause failure but are the cause of a
299 * persistent failure not just 'timed out'
300 * @sk_drops: raw/udp drops counter
301 * @sk_ack_backlog: current listen backlog
302 * @sk_max_ack_backlog: listen backlog set in listen()
303 * @sk_uid: user id of owner
304 * @sk_prefer_busy_poll: prefer busypolling over softirq processing
305 * @sk_busy_poll_budget: napi processing budget when busypolling
306 * @sk_priority: %SO_PRIORITY setting
307 * @sk_type: socket type (%SOCK_STREAM, etc)
308 * @sk_protocol: which protocol this socket belongs in this network family
309 * @sk_peer_pid: &struct pid for this socket's peer
310 * @sk_peer_cred: %SO_PEERCRED setting
311 * @sk_rcvlowat: %SO_RCVLOWAT setting
312 * @sk_rcvtimeo: %SO_RCVTIMEO setting
313 * @sk_sndtimeo: %SO_SNDTIMEO setting
314 * @sk_txhash: computed flow hash for use on transmit
315 * @sk_filter: socket filtering instructions
316 * @sk_timer: sock cleanup timer
317 * @sk_stamp: time stamp of last packet received
318 * @sk_stamp_seq: lock for accessing sk_stamp on 32 bit architectures only
319 * @sk_tsflags: SO_TIMESTAMPING flags
320 * @sk_bind_phc: SO_TIMESTAMPING bind PHC index of PTP virtual clock
322 * @sk_tskey: counter to disambiguate concurrent tstamp requests
323 * @sk_zckey: counter to order MSG_ZEROCOPY notifications
324 * @sk_socket: Identd and reporting IO signals
325 * @sk_user_data: RPC layer private data
326 * @sk_frag: cached page frag
327 * @sk_peek_off: current peek_offset value
328 * @sk_send_head: front of stuff to transmit
329 * @tcp_rtx_queue: TCP re-transmit queue [union with @sk_send_head]
330 * @sk_tx_skb_cache: cache copy of recently accessed TX skb
331 * @sk_security: used by security modules
332 * @sk_mark: generic packet mark
333 * @sk_cgrp_data: cgroup data for this cgroup
334 * @sk_memcg: this socket's memory cgroup association
335 * @sk_write_pending: a write to stream socket waits to start
336 * @sk_state_change: callback to indicate change in the state of the sock
337 * @sk_data_ready: callback to indicate there is data to be processed
338 * @sk_write_space: callback to indicate there is bf sending space available
339 * @sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
340 * @sk_backlog_rcv: callback to process the backlog
341 * @sk_validate_xmit_skb: ptr to an optional validate function
342 * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
343 * @sk_reuseport_cb: reuseport group container
344 * @sk_bpf_storage: ptr to cache and control for bpf_sk_storage
345 * @sk_rcu: used during RCU grace period
346 * @sk_clockid: clockid used by time-based scheduling (SO_TXTIME)
347 * @sk_txtime_deadline_mode: set deadline mode for SO_TXTIME
348 * @sk_txtime_report_errors: set report errors mode for SO_TXTIME
349 * @sk_txtime_unused: unused txtime flags
353 * Now struct inet_timewait_sock also uses sock_common, so please just
354 * don't add nothing before this first member (__sk_common) --acme
356 struct sock_common __sk_common;
357 #define sk_node __sk_common.skc_node
358 #define sk_nulls_node __sk_common.skc_nulls_node
359 #define sk_refcnt __sk_common.skc_refcnt
360 #define sk_tx_queue_mapping __sk_common.skc_tx_queue_mapping
361 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
362 #define sk_rx_queue_mapping __sk_common.skc_rx_queue_mapping
365 #define sk_dontcopy_begin __sk_common.skc_dontcopy_begin
366 #define sk_dontcopy_end __sk_common.skc_dontcopy_end
367 #define sk_hash __sk_common.skc_hash
368 #define sk_portpair __sk_common.skc_portpair
369 #define sk_num __sk_common.skc_num
370 #define sk_dport __sk_common.skc_dport
371 #define sk_addrpair __sk_common.skc_addrpair
372 #define sk_daddr __sk_common.skc_daddr
373 #define sk_rcv_saddr __sk_common.skc_rcv_saddr
374 #define sk_family __sk_common.skc_family
375 #define sk_state __sk_common.skc_state
376 #define sk_reuse __sk_common.skc_reuse
377 #define sk_reuseport __sk_common.skc_reuseport
378 #define sk_ipv6only __sk_common.skc_ipv6only
379 #define sk_net_refcnt __sk_common.skc_net_refcnt
380 #define sk_bound_dev_if __sk_common.skc_bound_dev_if
381 #define sk_bind_node __sk_common.skc_bind_node
382 #define sk_prot __sk_common.skc_prot
383 #define sk_net __sk_common.skc_net
384 #define sk_v6_daddr __sk_common.skc_v6_daddr
385 #define sk_v6_rcv_saddr __sk_common.skc_v6_rcv_saddr
386 #define sk_cookie __sk_common.skc_cookie
387 #define sk_incoming_cpu __sk_common.skc_incoming_cpu
388 #define sk_flags __sk_common.skc_flags
389 #define sk_rxhash __sk_common.skc_rxhash
391 socket_lock_t sk_lock;
394 struct sk_buff_head sk_error_queue;
395 struct sk_buff *sk_rx_skb_cache;
396 struct sk_buff_head sk_receive_queue;
398 * The backlog queue is special, it is always used with
399 * the per-socket spinlock held and requires low latency
400 * access. Therefore we special case it's implementation.
401 * Note : rmem_alloc is in this structure to fill a hole
402 * on 64bit arches, not because its logically part of
408 struct sk_buff *head;
409 struct sk_buff *tail;
411 #define sk_rmem_alloc sk_backlog.rmem_alloc
413 int sk_forward_alloc;
414 #ifdef CONFIG_NET_RX_BUSY_POLL
415 unsigned int sk_ll_usec;
416 /* ===== mostly read cache line ===== */
417 unsigned int sk_napi_id;
421 struct sk_filter __rcu *sk_filter;
423 struct socket_wq __rcu *sk_wq;
425 struct socket_wq *sk_wq_raw;
429 struct xfrm_policy __rcu *sk_policy[2];
431 struct dst_entry *sk_rx_dst;
432 struct dst_entry __rcu *sk_dst_cache;
433 atomic_t sk_omem_alloc;
436 /* ===== cache line for TX ===== */
438 refcount_t sk_wmem_alloc;
439 unsigned long sk_tsq_flags;
441 struct sk_buff *sk_send_head;
442 struct rb_root tcp_rtx_queue;
444 struct sk_buff *sk_tx_skb_cache;
445 struct sk_buff_head sk_write_queue;
447 int sk_write_pending;
448 __u32 sk_dst_pending_confirm;
449 u32 sk_pacing_status; /* see enum sk_pacing */
451 struct timer_list sk_timer;
454 unsigned long sk_pacing_rate; /* bytes per second */
455 unsigned long sk_max_pacing_rate;
456 struct page_frag sk_frag;
457 netdev_features_t sk_route_caps;
458 netdev_features_t sk_route_nocaps;
459 netdev_features_t sk_route_forced_caps;
461 unsigned int sk_gso_max_size;
466 * Because of non atomicity rules, all
467 * changes are protected by socket lock.
478 unsigned long sk_lingertime;
479 struct proto *sk_prot_creator;
480 rwlock_t sk_callback_lock;
484 u32 sk_max_ack_backlog;
486 #ifdef CONFIG_NET_RX_BUSY_POLL
487 u8 sk_prefer_busy_poll;
488 u16 sk_busy_poll_budget;
490 struct pid *sk_peer_pid;
491 const struct cred *sk_peer_cred;
494 #if BITS_PER_LONG==32
495 seqlock_t sk_stamp_seq;
504 u8 sk_txtime_deadline_mode : 1,
505 sk_txtime_report_errors : 1,
506 sk_txtime_unused : 6;
508 struct socket *sk_socket;
510 #ifdef CONFIG_SECURITY
513 struct sock_cgroup_data sk_cgrp_data;
514 struct mem_cgroup *sk_memcg;
515 void (*sk_state_change)(struct sock *sk);
516 void (*sk_data_ready)(struct sock *sk);
517 void (*sk_write_space)(struct sock *sk);
518 void (*sk_error_report)(struct sock *sk);
519 int (*sk_backlog_rcv)(struct sock *sk,
520 struct sk_buff *skb);
521 #ifdef CONFIG_SOCK_VALIDATE_XMIT
522 struct sk_buff* (*sk_validate_xmit_skb)(struct sock *sk,
523 struct net_device *dev,
524 struct sk_buff *skb);
526 void (*sk_destruct)(struct sock *sk);
527 struct sock_reuseport __rcu *sk_reuseport_cb;
528 #ifdef CONFIG_BPF_SYSCALL
529 struct bpf_local_storage __rcu *sk_bpf_storage;
531 struct rcu_head sk_rcu;
536 SK_PACING_NEEDED = 1,
540 /* Pointer stored in sk_user_data might not be suitable for copying
541 * when cloning the socket. For instance, it can point to a reference
542 * counted object. sk_user_data bottom bit is set if pointer must not
545 #define SK_USER_DATA_NOCOPY 1UL
546 #define SK_USER_DATA_BPF 2UL /* Managed by BPF */
547 #define SK_USER_DATA_PTRMASK ~(SK_USER_DATA_NOCOPY | SK_USER_DATA_BPF)
550 * sk_user_data_is_nocopy - Test if sk_user_data pointer must not be copied
553 static inline bool sk_user_data_is_nocopy(const struct sock *sk)
555 return ((uintptr_t)sk->sk_user_data & SK_USER_DATA_NOCOPY);
558 #define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data)))
560 #define rcu_dereference_sk_user_data(sk) \
562 void *__tmp = rcu_dereference(__sk_user_data((sk))); \
563 (void *)((uintptr_t)__tmp & SK_USER_DATA_PTRMASK); \
565 #define rcu_assign_sk_user_data(sk, ptr) \
567 uintptr_t __tmp = (uintptr_t)(ptr); \
568 WARN_ON_ONCE(__tmp & ~SK_USER_DATA_PTRMASK); \
569 rcu_assign_pointer(__sk_user_data((sk)), __tmp); \
571 #define rcu_assign_sk_user_data_nocopy(sk, ptr) \
573 uintptr_t __tmp = (uintptr_t)(ptr); \
574 WARN_ON_ONCE(__tmp & ~SK_USER_DATA_PTRMASK); \
575 rcu_assign_pointer(__sk_user_data((sk)), \
576 __tmp | SK_USER_DATA_NOCOPY); \
580 * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK
581 * or not whether his port will be reused by someone else. SK_FORCE_REUSE
582 * on a socket means that the socket will reuse everybody else's port
583 * without looking at the other's sk_reuse value.
586 #define SK_NO_REUSE 0
587 #define SK_CAN_REUSE 1
588 #define SK_FORCE_REUSE 2
590 int sk_set_peek_off(struct sock *sk, int val);
592 static inline int sk_peek_offset(struct sock *sk, int flags)
594 if (unlikely(flags & MSG_PEEK)) {
595 return READ_ONCE(sk->sk_peek_off);
601 static inline void sk_peek_offset_bwd(struct sock *sk, int val)
603 s32 off = READ_ONCE(sk->sk_peek_off);
605 if (unlikely(off >= 0)) {
606 off = max_t(s32, off - val, 0);
607 WRITE_ONCE(sk->sk_peek_off, off);
611 static inline void sk_peek_offset_fwd(struct sock *sk, int val)
613 sk_peek_offset_bwd(sk, -val);
617 * Hashed lists helper routines
619 static inline struct sock *sk_entry(const struct hlist_node *node)
621 return hlist_entry(node, struct sock, sk_node);
624 static inline struct sock *__sk_head(const struct hlist_head *head)
626 return hlist_entry(head->first, struct sock, sk_node);
629 static inline struct sock *sk_head(const struct hlist_head *head)
631 return hlist_empty(head) ? NULL : __sk_head(head);
634 static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head)
636 return hlist_nulls_entry(head->first, struct sock, sk_nulls_node);
639 static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head)
641 return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head);
644 static inline struct sock *sk_next(const struct sock *sk)
646 return hlist_entry_safe(sk->sk_node.next, struct sock, sk_node);
649 static inline struct sock *sk_nulls_next(const struct sock *sk)
651 return (!is_a_nulls(sk->sk_nulls_node.next)) ?
652 hlist_nulls_entry(sk->sk_nulls_node.next,
653 struct sock, sk_nulls_node) :
657 static inline bool sk_unhashed(const struct sock *sk)
659 return hlist_unhashed(&sk->sk_node);
662 static inline bool sk_hashed(const struct sock *sk)
664 return !sk_unhashed(sk);
667 static inline void sk_node_init(struct hlist_node *node)
672 static inline void sk_nulls_node_init(struct hlist_nulls_node *node)
677 static inline void __sk_del_node(struct sock *sk)
679 __hlist_del(&sk->sk_node);
682 /* NB: equivalent to hlist_del_init_rcu */
683 static inline bool __sk_del_node_init(struct sock *sk)
687 sk_node_init(&sk->sk_node);
693 /* Grab socket reference count. This operation is valid only
694 when sk is ALREADY grabbed f.e. it is found in hash table
695 or a list and the lookup is made under lock preventing hash table
699 static __always_inline void sock_hold(struct sock *sk)
701 refcount_inc(&sk->sk_refcnt);
704 /* Ungrab socket in the context, which assumes that socket refcnt
705 cannot hit zero, f.e. it is true in context of any socketcall.
707 static __always_inline void __sock_put(struct sock *sk)
709 refcount_dec(&sk->sk_refcnt);
712 static inline bool sk_del_node_init(struct sock *sk)
714 bool rc = __sk_del_node_init(sk);
717 /* paranoid for a while -acme */
718 WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
723 #define sk_del_node_init_rcu(sk) sk_del_node_init(sk)
725 static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk)
728 hlist_nulls_del_init_rcu(&sk->sk_nulls_node);
734 static inline bool sk_nulls_del_node_init_rcu(struct sock *sk)
736 bool rc = __sk_nulls_del_node_init_rcu(sk);
739 /* paranoid for a while -acme */
740 WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
746 static inline void __sk_add_node(struct sock *sk, struct hlist_head *list)
748 hlist_add_head(&sk->sk_node, list);
751 static inline void sk_add_node(struct sock *sk, struct hlist_head *list)
754 __sk_add_node(sk, list);
757 static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list)
760 if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport &&
761 sk->sk_family == AF_INET6)
762 hlist_add_tail_rcu(&sk->sk_node, list);
764 hlist_add_head_rcu(&sk->sk_node, list);
767 static inline void sk_add_node_tail_rcu(struct sock *sk, struct hlist_head *list)
770 hlist_add_tail_rcu(&sk->sk_node, list);
773 static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
775 hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list);
778 static inline void __sk_nulls_add_node_tail_rcu(struct sock *sk, struct hlist_nulls_head *list)
780 hlist_nulls_add_tail_rcu(&sk->sk_nulls_node, list);
783 static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
786 __sk_nulls_add_node_rcu(sk, list);
789 static inline void __sk_del_bind_node(struct sock *sk)
791 __hlist_del(&sk->sk_bind_node);
794 static inline void sk_add_bind_node(struct sock *sk,
795 struct hlist_head *list)
797 hlist_add_head(&sk->sk_bind_node, list);
800 #define sk_for_each(__sk, list) \
801 hlist_for_each_entry(__sk, list, sk_node)
802 #define sk_for_each_rcu(__sk, list) \
803 hlist_for_each_entry_rcu(__sk, list, sk_node)
804 #define sk_nulls_for_each(__sk, node, list) \
805 hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)
806 #define sk_nulls_for_each_rcu(__sk, node, list) \
807 hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)
808 #define sk_for_each_from(__sk) \
809 hlist_for_each_entry_from(__sk, sk_node)
810 #define sk_nulls_for_each_from(__sk, node) \
811 if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \
812 hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node)
813 #define sk_for_each_safe(__sk, tmp, list) \
814 hlist_for_each_entry_safe(__sk, tmp, list, sk_node)
815 #define sk_for_each_bound(__sk, list) \
816 hlist_for_each_entry(__sk, list, sk_bind_node)
819 * sk_for_each_entry_offset_rcu - iterate over a list at a given struct offset
820 * @tpos: the type * to use as a loop cursor.
821 * @pos: the &struct hlist_node to use as a loop cursor.
822 * @head: the head for your list.
823 * @offset: offset of hlist_node within the struct.
826 #define sk_for_each_entry_offset_rcu(tpos, pos, head, offset) \
827 for (pos = rcu_dereference(hlist_first_rcu(head)); \
829 ({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;}); \
830 pos = rcu_dereference(hlist_next_rcu(pos)))
832 static inline struct user_namespace *sk_user_ns(struct sock *sk)
834 /* Careful only use this in a context where these parameters
835 * can not change and must all be valid, such as recvmsg from
838 return sk->sk_socket->file->f_cred->user_ns;
852 SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */
853 SOCK_DBG, /* %SO_DEBUG setting */
854 SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
855 SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */
856 SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
857 SOCK_MEMALLOC, /* VM depends on this socket for swapping */
858 SOCK_TIMESTAMPING_RX_SOFTWARE, /* %SOF_TIMESTAMPING_RX_SOFTWARE */
859 SOCK_FASYNC, /* fasync() active */
861 SOCK_ZEROCOPY, /* buffers from userspace */
862 SOCK_WIFI_STATUS, /* push wifi status to userspace */
863 SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS.
864 * Will use last 4 bytes of packet sent from
865 * user-space instead.
867 SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */
868 SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */
869 SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */
871 SOCK_XDP, /* XDP is attached */
872 SOCK_TSTAMP_NEW, /* Indicates 64 bit timestamps always */
875 #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))
877 static inline void sock_copy_flags(struct sock *nsk, struct sock *osk)
879 nsk->sk_flags = osk->sk_flags;
882 static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
884 __set_bit(flag, &sk->sk_flags);
887 static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag)
889 __clear_bit(flag, &sk->sk_flags);
892 static inline void sock_valbool_flag(struct sock *sk, enum sock_flags bit,
896 sock_set_flag(sk, bit);
898 sock_reset_flag(sk, bit);
901 static inline bool sock_flag(const struct sock *sk, enum sock_flags flag)
903 return test_bit(flag, &sk->sk_flags);
907 DECLARE_STATIC_KEY_FALSE(memalloc_socks_key);
908 static inline int sk_memalloc_socks(void)
910 return static_branch_unlikely(&memalloc_socks_key);
913 void __receive_sock(struct file *file);
916 static inline int sk_memalloc_socks(void)
921 static inline void __receive_sock(struct file *file)
925 static inline gfp_t sk_gfp_mask(const struct sock *sk, gfp_t gfp_mask)
927 return gfp_mask | (sk->sk_allocation & __GFP_MEMALLOC);
930 static inline void sk_acceptq_removed(struct sock *sk)
932 WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog - 1);
935 static inline void sk_acceptq_added(struct sock *sk)
937 WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog + 1);
940 /* Note: If you think the test should be:
941 * return READ_ONCE(sk->sk_ack_backlog) >= READ_ONCE(sk->sk_max_ack_backlog);
942 * Then please take a look at commit 64a146513f8f ("[NET]: Revert incorrect accept queue backlog changes.")
944 static inline bool sk_acceptq_is_full(const struct sock *sk)
946 return READ_ONCE(sk->sk_ack_backlog) > READ_ONCE(sk->sk_max_ack_backlog);
950 * Compute minimal free write space needed to queue new packets.
952 static inline int sk_stream_min_wspace(const struct sock *sk)
954 return READ_ONCE(sk->sk_wmem_queued) >> 1;
957 static inline int sk_stream_wspace(const struct sock *sk)
959 return READ_ONCE(sk->sk_sndbuf) - READ_ONCE(sk->sk_wmem_queued);
962 static inline void sk_wmem_queued_add(struct sock *sk, int val)
964 WRITE_ONCE(sk->sk_wmem_queued, sk->sk_wmem_queued + val);
967 void sk_stream_write_space(struct sock *sk);
969 /* OOB backlog add */
970 static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
972 /* dont let skb dst not refcounted, we are going to leave rcu lock */
975 if (!sk->sk_backlog.tail)
976 WRITE_ONCE(sk->sk_backlog.head, skb);
978 sk->sk_backlog.tail->next = skb;
980 WRITE_ONCE(sk->sk_backlog.tail, skb);
985 * Take into account size of receive queue and backlog queue
986 * Do not take into account this skb truesize,
987 * to allow even a single big packet to come.
989 static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit)
991 unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc);
993 return qsize > limit;
996 /* The per-socket spinlock must be held here. */
997 static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb,
1000 if (sk_rcvqueues_full(sk, limit))
1004 * If the skb was allocated from pfmemalloc reserves, only
1005 * allow SOCK_MEMALLOC sockets to use it as this socket is
1006 * helping free memory
1008 if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC))
1011 __sk_add_backlog(sk, skb);
1012 sk->sk_backlog.len += skb->truesize;
1016 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb);
1018 static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
1020 if (sk_memalloc_socks() && skb_pfmemalloc(skb))
1021 return __sk_backlog_rcv(sk, skb);
1023 return sk->sk_backlog_rcv(sk, skb);
1026 static inline void sk_incoming_cpu_update(struct sock *sk)
1028 int cpu = raw_smp_processor_id();
1030 if (unlikely(READ_ONCE(sk->sk_incoming_cpu) != cpu))
1031 WRITE_ONCE(sk->sk_incoming_cpu, cpu);
1034 static inline void sock_rps_record_flow_hash(__u32 hash)
1037 struct rps_sock_flow_table *sock_flow_table;
1040 sock_flow_table = rcu_dereference(rps_sock_flow_table);
1041 rps_record_sock_flow(sock_flow_table, hash);
1046 static inline void sock_rps_record_flow(const struct sock *sk)
1049 if (static_branch_unlikely(&rfs_needed)) {
1050 /* Reading sk->sk_rxhash might incur an expensive cache line
1053 * TCP_ESTABLISHED does cover almost all states where RFS
1054 * might be useful, and is cheaper [1] than testing :
1055 * IPv4: inet_sk(sk)->inet_daddr
1056 * IPv6: ipv6_addr_any(&sk->sk_v6_daddr)
1057 * OR an additional socket flag
1058 * [1] : sk_state and sk_prot are in the same cache line.
1060 if (sk->sk_state == TCP_ESTABLISHED)
1061 sock_rps_record_flow_hash(sk->sk_rxhash);
1066 static inline void sock_rps_save_rxhash(struct sock *sk,
1067 const struct sk_buff *skb)
1070 if (unlikely(sk->sk_rxhash != skb->hash))
1071 sk->sk_rxhash = skb->hash;
1075 static inline void sock_rps_reset_rxhash(struct sock *sk)
1082 #define sk_wait_event(__sk, __timeo, __condition, __wait) \
1084 release_sock(__sk); \
1085 __rc = __condition; \
1087 *(__timeo) = wait_woken(__wait, \
1088 TASK_INTERRUPTIBLE, \
1091 sched_annotate_sleep(); \
1093 __rc = __condition; \
1097 int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
1098 int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
1099 void sk_stream_wait_close(struct sock *sk, long timeo_p);
1100 int sk_stream_error(struct sock *sk, int flags, int err);
1101 void sk_stream_kill_queues(struct sock *sk);
1102 void sk_set_memalloc(struct sock *sk);
1103 void sk_clear_memalloc(struct sock *sk);
1105 void __sk_flush_backlog(struct sock *sk);
1107 static inline bool sk_flush_backlog(struct sock *sk)
1109 if (unlikely(READ_ONCE(sk->sk_backlog.tail))) {
1110 __sk_flush_backlog(sk);
1116 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb);
1118 struct request_sock_ops;
1119 struct timewait_sock_ops;
1120 struct inet_hashinfo;
1121 struct raw_hashinfo;
1122 struct smc_hashinfo;
1127 * caches using SLAB_TYPESAFE_BY_RCU should let .next pointer from nulls nodes
1128 * un-modified. Special care is taken when initializing object to zero.
1130 static inline void sk_prot_clear_nulls(struct sock *sk, int size)
1132 if (offsetof(struct sock, sk_node.next) != 0)
1133 memset(sk, 0, offsetof(struct sock, sk_node.next));
1134 memset(&sk->sk_node.pprev, 0,
1135 size - offsetof(struct sock, sk_node.pprev));
1138 /* Networking protocol blocks we attach to sockets.
1139 * socket layer -> transport layer interface
1142 void (*close)(struct sock *sk,
1144 int (*pre_connect)(struct sock *sk,
1145 struct sockaddr *uaddr,
1147 int (*connect)(struct sock *sk,
1148 struct sockaddr *uaddr,
1150 int (*disconnect)(struct sock *sk, int flags);
1152 struct sock * (*accept)(struct sock *sk, int flags, int *err,
1155 int (*ioctl)(struct sock *sk, int cmd,
1157 int (*init)(struct sock *sk);
1158 void (*destroy)(struct sock *sk);
1159 void (*shutdown)(struct sock *sk, int how);
1160 int (*setsockopt)(struct sock *sk, int level,
1161 int optname, sockptr_t optval,
1162 unsigned int optlen);
1163 int (*getsockopt)(struct sock *sk, int level,
1164 int optname, char __user *optval,
1165 int __user *option);
1166 void (*keepalive)(struct sock *sk, int valbool);
1167 #ifdef CONFIG_COMPAT
1168 int (*compat_ioctl)(struct sock *sk,
1169 unsigned int cmd, unsigned long arg);
1171 int (*sendmsg)(struct sock *sk, struct msghdr *msg,
1173 int (*recvmsg)(struct sock *sk, struct msghdr *msg,
1174 size_t len, int noblock, int flags,
1176 int (*sendpage)(struct sock *sk, struct page *page,
1177 int offset, size_t size, int flags);
1178 int (*bind)(struct sock *sk,
1179 struct sockaddr *addr, int addr_len);
1180 int (*bind_add)(struct sock *sk,
1181 struct sockaddr *addr, int addr_len);
1183 int (*backlog_rcv) (struct sock *sk,
1184 struct sk_buff *skb);
1185 bool (*bpf_bypass_getsockopt)(int level,
1188 void (*release_cb)(struct sock *sk);
1190 /* Keeping track of sk's, looking them up, and port selection methods. */
1191 int (*hash)(struct sock *sk);
1192 void (*unhash)(struct sock *sk);
1193 void (*rehash)(struct sock *sk);
1194 int (*get_port)(struct sock *sk, unsigned short snum);
1195 #ifdef CONFIG_BPF_SYSCALL
1196 int (*psock_update_sk_prot)(struct sock *sk,
1197 struct sk_psock *psock,
1201 /* Keeping track of sockets in use */
1202 #ifdef CONFIG_PROC_FS
1203 unsigned int inuse_idx;
1206 bool (*stream_memory_free)(const struct sock *sk, int wake);
1207 bool (*stream_memory_read)(const struct sock *sk);
1208 /* Memory pressure */
1209 void (*enter_memory_pressure)(struct sock *sk);
1210 void (*leave_memory_pressure)(struct sock *sk);
1211 atomic_long_t *memory_allocated; /* Current allocated memory. */
1212 struct percpu_counter *sockets_allocated; /* Current number of sockets. */
1214 * Pressure flag: try to collapse.
1215 * Technical note: it is used by multiple contexts non atomically.
1216 * All the __sk_mem_schedule() is of this nature: accounting
1217 * is strict, actions are advisory and have some latency.
1219 unsigned long *memory_pressure;
1224 u32 sysctl_wmem_offset;
1225 u32 sysctl_rmem_offset;
1230 struct kmem_cache *slab;
1231 unsigned int obj_size;
1232 slab_flags_t slab_flags;
1233 unsigned int useroffset; /* Usercopy region offset */
1234 unsigned int usersize; /* Usercopy region size */
1236 struct percpu_counter *orphan_count;
1238 struct request_sock_ops *rsk_prot;
1239 struct timewait_sock_ops *twsk_prot;
1242 struct inet_hashinfo *hashinfo;
1243 struct udp_table *udp_table;
1244 struct raw_hashinfo *raw_hash;
1245 struct smc_hashinfo *smc_hash;
1248 struct module *owner;
1252 struct list_head node;
1253 #ifdef SOCK_REFCNT_DEBUG
1256 int (*diag_destroy)(struct sock *sk, int err);
1257 } __randomize_layout;
1259 int proto_register(struct proto *prot, int alloc_slab);
1260 void proto_unregister(struct proto *prot);
1261 int sock_load_diag_module(int family, int protocol);
1263 #ifdef SOCK_REFCNT_DEBUG
1264 static inline void sk_refcnt_debug_inc(struct sock *sk)
1266 atomic_inc(&sk->sk_prot->socks);
1269 static inline void sk_refcnt_debug_dec(struct sock *sk)
1271 atomic_dec(&sk->sk_prot->socks);
1272 printk(KERN_DEBUG "%s socket %p released, %d are still alive\n",
1273 sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks));
1276 static inline void sk_refcnt_debug_release(const struct sock *sk)
1278 if (refcount_read(&sk->sk_refcnt) != 1)
1279 printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n",
1280 sk->sk_prot->name, sk, refcount_read(&sk->sk_refcnt));
1282 #else /* SOCK_REFCNT_DEBUG */
1283 #define sk_refcnt_debug_inc(sk) do { } while (0)
1284 #define sk_refcnt_debug_dec(sk) do { } while (0)
1285 #define sk_refcnt_debug_release(sk) do { } while (0)
1286 #endif /* SOCK_REFCNT_DEBUG */
1288 INDIRECT_CALLABLE_DECLARE(bool tcp_stream_memory_free(const struct sock *sk, int wake));
1290 static inline bool __sk_stream_memory_free(const struct sock *sk, int wake)
1292 if (READ_ONCE(sk->sk_wmem_queued) >= READ_ONCE(sk->sk_sndbuf))
1296 return sk->sk_prot->stream_memory_free ?
1297 INDIRECT_CALL_1(sk->sk_prot->stream_memory_free,
1298 tcp_stream_memory_free,
1301 return sk->sk_prot->stream_memory_free ?
1302 sk->sk_prot->stream_memory_free(sk, wake) : true;
1306 static inline bool sk_stream_memory_free(const struct sock *sk)
1308 return __sk_stream_memory_free(sk, 0);
1311 static inline bool __sk_stream_is_writeable(const struct sock *sk, int wake)
1313 return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) &&
1314 __sk_stream_memory_free(sk, wake);
1317 static inline bool sk_stream_is_writeable(const struct sock *sk)
1319 return __sk_stream_is_writeable(sk, 0);
1322 static inline int sk_under_cgroup_hierarchy(struct sock *sk,
1323 struct cgroup *ancestor)
1325 #ifdef CONFIG_SOCK_CGROUP_DATA
1326 return cgroup_is_descendant(sock_cgroup_ptr(&sk->sk_cgrp_data),
1333 static inline bool sk_has_memory_pressure(const struct sock *sk)
1335 return sk->sk_prot->memory_pressure != NULL;
1338 static inline bool sk_under_memory_pressure(const struct sock *sk)
1340 if (!sk->sk_prot->memory_pressure)
1343 if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
1344 mem_cgroup_under_socket_pressure(sk->sk_memcg))
1347 return !!*sk->sk_prot->memory_pressure;
1351 sk_memory_allocated(const struct sock *sk)
1353 return atomic_long_read(sk->sk_prot->memory_allocated);
1357 sk_memory_allocated_add(struct sock *sk, int amt)
1359 return atomic_long_add_return(amt, sk->sk_prot->memory_allocated);
1363 sk_memory_allocated_sub(struct sock *sk, int amt)
1365 atomic_long_sub(amt, sk->sk_prot->memory_allocated);
1368 #define SK_ALLOC_PERCPU_COUNTER_BATCH 16
1370 static inline void sk_sockets_allocated_dec(struct sock *sk)
1372 percpu_counter_add_batch(sk->sk_prot->sockets_allocated, -1,
1373 SK_ALLOC_PERCPU_COUNTER_BATCH);
1376 static inline void sk_sockets_allocated_inc(struct sock *sk)
1378 percpu_counter_add_batch(sk->sk_prot->sockets_allocated, 1,
1379 SK_ALLOC_PERCPU_COUNTER_BATCH);
1383 sk_sockets_allocated_read_positive(struct sock *sk)
1385 return percpu_counter_read_positive(sk->sk_prot->sockets_allocated);
1389 proto_sockets_allocated_sum_positive(struct proto *prot)
1391 return percpu_counter_sum_positive(prot->sockets_allocated);
1395 proto_memory_allocated(struct proto *prot)
1397 return atomic_long_read(prot->memory_allocated);
1401 proto_memory_pressure(struct proto *prot)
1403 if (!prot->memory_pressure)
1405 return !!*prot->memory_pressure;
1409 #ifdef CONFIG_PROC_FS
1410 /* Called with local bh disabled */
1411 void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc);
1412 int sock_prot_inuse_get(struct net *net, struct proto *proto);
1413 int sock_inuse_get(struct net *net);
1415 static inline void sock_prot_inuse_add(struct net *net, struct proto *prot,
1422 /* With per-bucket locks this operation is not-atomic, so that
1423 * this version is not worse.
1425 static inline int __sk_prot_rehash(struct sock *sk)
1427 sk->sk_prot->unhash(sk);
1428 return sk->sk_prot->hash(sk);
1431 /* About 10 seconds */
1432 #define SOCK_DESTROY_TIME (10*HZ)
1434 /* Sockets 0-1023 can't be bound to unless you are superuser */
1435 #define PROT_SOCK 1024
1437 #define SHUTDOWN_MASK 3
1438 #define RCV_SHUTDOWN 1
1439 #define SEND_SHUTDOWN 2
1441 #define SOCK_SNDBUF_LOCK 1
1442 #define SOCK_RCVBUF_LOCK 2
1443 #define SOCK_BINDADDR_LOCK 4
1444 #define SOCK_BINDPORT_LOCK 8
1446 struct socket_alloc {
1447 struct socket socket;
1448 struct inode vfs_inode;
1451 static inline struct socket *SOCKET_I(struct inode *inode)
1453 return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
1456 static inline struct inode *SOCK_INODE(struct socket *socket)
1458 return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
1462 * Functions for memory accounting
1464 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind);
1465 int __sk_mem_schedule(struct sock *sk, int size, int kind);
1466 void __sk_mem_reduce_allocated(struct sock *sk, int amount);
1467 void __sk_mem_reclaim(struct sock *sk, int amount);
1469 /* We used to have PAGE_SIZE here, but systems with 64KB pages
1470 * do not necessarily have 16x time more memory than 4KB ones.
1472 #define SK_MEM_QUANTUM 4096
1473 #define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM)
1474 #define SK_MEM_SEND 0
1475 #define SK_MEM_RECV 1
1477 /* sysctl_mem values are in pages, we convert them in SK_MEM_QUANTUM units */
1478 static inline long sk_prot_mem_limits(const struct sock *sk, int index)
1480 long val = sk->sk_prot->sysctl_mem[index];
1482 #if PAGE_SIZE > SK_MEM_QUANTUM
1483 val <<= PAGE_SHIFT - SK_MEM_QUANTUM_SHIFT;
1484 #elif PAGE_SIZE < SK_MEM_QUANTUM
1485 val >>= SK_MEM_QUANTUM_SHIFT - PAGE_SHIFT;
1490 static inline int sk_mem_pages(int amt)
1492 return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT;
1495 static inline bool sk_has_account(struct sock *sk)
1497 /* return true if protocol supports memory accounting */
1498 return !!sk->sk_prot->memory_allocated;
1501 static inline bool sk_wmem_schedule(struct sock *sk, int size)
1503 if (!sk_has_account(sk))
1505 return size <= sk->sk_forward_alloc ||
1506 __sk_mem_schedule(sk, size, SK_MEM_SEND);
1510 sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size)
1512 if (!sk_has_account(sk))
1514 return size <= sk->sk_forward_alloc ||
1515 __sk_mem_schedule(sk, size, SK_MEM_RECV) ||
1516 skb_pfmemalloc(skb);
1519 static inline void sk_mem_reclaim(struct sock *sk)
1521 if (!sk_has_account(sk))
1523 if (sk->sk_forward_alloc >= SK_MEM_QUANTUM)
1524 __sk_mem_reclaim(sk, sk->sk_forward_alloc);
1527 static inline void sk_mem_reclaim_partial(struct sock *sk)
1529 if (!sk_has_account(sk))
1531 if (sk->sk_forward_alloc > SK_MEM_QUANTUM)
1532 __sk_mem_reclaim(sk, sk->sk_forward_alloc - 1);
1535 static inline void sk_mem_charge(struct sock *sk, int size)
1537 if (!sk_has_account(sk))
1539 sk->sk_forward_alloc -= size;
1542 static inline void sk_mem_uncharge(struct sock *sk, int size)
1544 if (!sk_has_account(sk))
1546 sk->sk_forward_alloc += size;
1548 /* Avoid a possible overflow.
1549 * TCP send queues can make this happen, if sk_mem_reclaim()
1550 * is not called and more than 2 GBytes are released at once.
1552 * If we reach 2 MBytes, reclaim 1 MBytes right now, there is
1553 * no need to hold that much forward allocation anyway.
1555 if (unlikely(sk->sk_forward_alloc >= 1 << 21))
1556 __sk_mem_reclaim(sk, 1 << 20);
1559 DECLARE_STATIC_KEY_FALSE(tcp_tx_skb_cache_key);
1560 static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb)
1562 sk_wmem_queued_add(sk, -skb->truesize);
1563 sk_mem_uncharge(sk, skb->truesize);
1564 if (static_branch_unlikely(&tcp_tx_skb_cache_key) &&
1565 !sk->sk_tx_skb_cache && !skb_cloned(skb)) {
1567 skb_zcopy_clear(skb, true);
1568 sk->sk_tx_skb_cache = skb;
1574 static inline void sock_release_ownership(struct sock *sk)
1576 if (sk->sk_lock.owned) {
1577 sk->sk_lock.owned = 0;
1579 /* The sk_lock has mutex_unlock() semantics: */
1580 mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
1585 * Macro so as to not evaluate some arguments when
1586 * lockdep is not enabled.
1588 * Mark both the sk_lock and the sk_lock.slock as a
1589 * per-address-family lock class.
1591 #define sock_lock_init_class_and_name(sk, sname, skey, name, key) \
1593 sk->sk_lock.owned = 0; \
1594 init_waitqueue_head(&sk->sk_lock.wq); \
1595 spin_lock_init(&(sk)->sk_lock.slock); \
1596 debug_check_no_locks_freed((void *)&(sk)->sk_lock, \
1597 sizeof((sk)->sk_lock)); \
1598 lockdep_set_class_and_name(&(sk)->sk_lock.slock, \
1600 lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \
1603 static inline bool lockdep_sock_is_held(const struct sock *sk)
1605 return lockdep_is_held(&sk->sk_lock) ||
1606 lockdep_is_held(&sk->sk_lock.slock);
1609 void lock_sock_nested(struct sock *sk, int subclass);
1611 static inline void lock_sock(struct sock *sk)
1613 lock_sock_nested(sk, 0);
1616 void __lock_sock(struct sock *sk);
1617 void __release_sock(struct sock *sk);
1618 void release_sock(struct sock *sk);
1620 /* BH context may only use the following locking interface. */
1621 #define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock))
1622 #define bh_lock_sock_nested(__sk) \
1623 spin_lock_nested(&((__sk)->sk_lock.slock), \
1624 SINGLE_DEPTH_NESTING)
1625 #define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock))
1627 bool lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock);
1630 * unlock_sock_fast - complement of lock_sock_fast
1634 * fast unlock socket for user context.
1635 * If slow mode is on, we call regular release_sock()
1637 static inline void unlock_sock_fast(struct sock *sk, bool slow)
1638 __releases(&sk->sk_lock.slock)
1642 __release(&sk->sk_lock.slock);
1644 spin_unlock_bh(&sk->sk_lock.slock);
1648 /* Used by processes to "lock" a socket state, so that
1649 * interrupts and bottom half handlers won't change it
1650 * from under us. It essentially blocks any incoming
1651 * packets, so that we won't get any new data or any
1652 * packets that change the state of the socket.
1654 * While locked, BH processing will add new packets to
1655 * the backlog queue. This queue is processed by the
1656 * owner of the socket lock right before it is released.
1658 * Since ~2.3.5 it is also exclusive sleep lock serializing
1659 * accesses from user process context.
1662 static inline void sock_owned_by_me(const struct sock *sk)
1664 #ifdef CONFIG_LOCKDEP
1665 WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks);
1669 static inline bool sock_owned_by_user(const struct sock *sk)
1671 sock_owned_by_me(sk);
1672 return sk->sk_lock.owned;
1675 static inline bool sock_owned_by_user_nocheck(const struct sock *sk)
1677 return sk->sk_lock.owned;
1680 /* no reclassification while locks are held */
1681 static inline bool sock_allow_reclassification(const struct sock *csk)
1683 struct sock *sk = (struct sock *)csk;
1685 return !sk->sk_lock.owned && !spin_is_locked(&sk->sk_lock.slock);
1688 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1689 struct proto *prot, int kern);
1690 void sk_free(struct sock *sk);
1691 void sk_destruct(struct sock *sk);
1692 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority);
1693 void sk_free_unlock_clone(struct sock *sk);
1695 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1697 void __sock_wfree(struct sk_buff *skb);
1698 void sock_wfree(struct sk_buff *skb);
1699 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
1701 void skb_orphan_partial(struct sk_buff *skb);
1702 void sock_rfree(struct sk_buff *skb);
1703 void sock_efree(struct sk_buff *skb);
1705 void sock_edemux(struct sk_buff *skb);
1706 void sock_pfree(struct sk_buff *skb);
1708 #define sock_edemux sock_efree
1711 int sock_setsockopt(struct socket *sock, int level, int op,
1712 sockptr_t optval, unsigned int optlen);
1714 int sock_getsockopt(struct socket *sock, int level, int op,
1715 char __user *optval, int __user *optlen);
1716 int sock_gettstamp(struct socket *sock, void __user *userstamp,
1717 bool timeval, bool time32);
1718 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1719 int noblock, int *errcode);
1720 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1721 unsigned long data_len, int noblock,
1722 int *errcode, int max_page_order);
1723 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority);
1724 void sock_kfree_s(struct sock *sk, void *mem, int size);
1725 void sock_kzfree_s(struct sock *sk, void *mem, int size);
1726 void sk_send_sigurg(struct sock *sk);
1728 struct sockcm_cookie {
1734 static inline void sockcm_init(struct sockcm_cookie *sockc,
1735 const struct sock *sk)
1737 *sockc = (struct sockcm_cookie) { .tsflags = sk->sk_tsflags };
1740 int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg,
1741 struct sockcm_cookie *sockc);
1742 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
1743 struct sockcm_cookie *sockc);
1746 * Functions to fill in entries in struct proto_ops when a protocol
1747 * does not implement a particular function.
1749 int sock_no_bind(struct socket *, struct sockaddr *, int);
1750 int sock_no_connect(struct socket *, struct sockaddr *, int, int);
1751 int sock_no_socketpair(struct socket *, struct socket *);
1752 int sock_no_accept(struct socket *, struct socket *, int, bool);
1753 int sock_no_getname(struct socket *, struct sockaddr *, int);
1754 int sock_no_ioctl(struct socket *, unsigned int, unsigned long);
1755 int sock_no_listen(struct socket *, int);
1756 int sock_no_shutdown(struct socket *, int);
1757 int sock_no_sendmsg(struct socket *, struct msghdr *, size_t);
1758 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len);
1759 int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int);
1760 int sock_no_mmap(struct file *file, struct socket *sock,
1761 struct vm_area_struct *vma);
1762 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset,
1763 size_t size, int flags);
1764 ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
1765 int offset, size_t size, int flags);
1768 * Functions to fill in entries in struct proto_ops when a protocol
1769 * uses the inet style.
1771 int sock_common_getsockopt(struct socket *sock, int level, int optname,
1772 char __user *optval, int __user *optlen);
1773 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1775 int sock_common_setsockopt(struct socket *sock, int level, int optname,
1776 sockptr_t optval, unsigned int optlen);
1778 void sk_common_release(struct sock *sk);
1781 * Default socket callbacks and setup code
1784 /* Initialise core socket variables */
1785 void sock_init_data(struct socket *sock, struct sock *sk);
1788 * Socket reference counting postulates.
1790 * * Each user of socket SHOULD hold a reference count.
1791 * * Each access point to socket (an hash table bucket, reference from a list,
1792 * running timer, skb in flight MUST hold a reference count.
1793 * * When reference count hits 0, it means it will never increase back.
1794 * * When reference count hits 0, it means that no references from
1795 * outside exist to this socket and current process on current CPU
1796 * is last user and may/should destroy this socket.
1797 * * sk_free is called from any context: process, BH, IRQ. When
1798 * it is called, socket has no references from outside -> sk_free
1799 * may release descendant resources allocated by the socket, but
1800 * to the time when it is called, socket is NOT referenced by any
1801 * hash tables, lists etc.
1802 * * Packets, delivered from outside (from network or from another process)
1803 * and enqueued on receive/error queues SHOULD NOT grab reference count,
1804 * when they sit in queue. Otherwise, packets will leak to hole, when
1805 * socket is looked up by one cpu and unhasing is made by another CPU.
1806 * It is true for udp/raw, netlink (leak to receive and error queues), tcp
1807 * (leak to backlog). Packet socket does all the processing inside
1808 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
1809 * use separate SMP lock, so that they are prone too.
1812 /* Ungrab socket and destroy it, if it was the last reference. */
1813 static inline void sock_put(struct sock *sk)
1815 if (refcount_dec_and_test(&sk->sk_refcnt))
1818 /* Generic version of sock_put(), dealing with all sockets
1819 * (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...)
1821 void sock_gen_put(struct sock *sk);
1823 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested,
1824 unsigned int trim_cap, bool refcounted);
1825 static inline int sk_receive_skb(struct sock *sk, struct sk_buff *skb,
1828 return __sk_receive_skb(sk, skb, nested, 1, true);
1831 static inline void sk_tx_queue_set(struct sock *sk, int tx_queue)
1833 /* sk_tx_queue_mapping accept only upto a 16-bit value */
1834 if (WARN_ON_ONCE((unsigned short)tx_queue >= USHRT_MAX))
1836 sk->sk_tx_queue_mapping = tx_queue;
1839 #define NO_QUEUE_MAPPING USHRT_MAX
1841 static inline void sk_tx_queue_clear(struct sock *sk)
1843 sk->sk_tx_queue_mapping = NO_QUEUE_MAPPING;
1846 static inline int sk_tx_queue_get(const struct sock *sk)
1848 if (sk && sk->sk_tx_queue_mapping != NO_QUEUE_MAPPING)
1849 return sk->sk_tx_queue_mapping;
1854 static inline void sk_rx_queue_set(struct sock *sk, const struct sk_buff *skb)
1856 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
1857 if (skb_rx_queue_recorded(skb)) {
1858 u16 rx_queue = skb_get_rx_queue(skb);
1860 if (WARN_ON_ONCE(rx_queue == NO_QUEUE_MAPPING))
1863 sk->sk_rx_queue_mapping = rx_queue;
1868 static inline void sk_rx_queue_clear(struct sock *sk)
1870 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
1871 sk->sk_rx_queue_mapping = NO_QUEUE_MAPPING;
1875 static inline int sk_rx_queue_get(const struct sock *sk)
1877 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
1878 if (sk && sk->sk_rx_queue_mapping != NO_QUEUE_MAPPING)
1879 return sk->sk_rx_queue_mapping;
1885 static inline void sk_set_socket(struct sock *sk, struct socket *sock)
1887 sk->sk_socket = sock;
1890 static inline wait_queue_head_t *sk_sleep(struct sock *sk)
1892 BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0);
1893 return &rcu_dereference_raw(sk->sk_wq)->wait;
1895 /* Detach socket from process context.
1896 * Announce socket dead, detach it from wait queue and inode.
1897 * Note that parent inode held reference count on this struct sock,
1898 * we do not release it in this function, because protocol
1899 * probably wants some additional cleanups or even continuing
1900 * to work with this socket (TCP).
1902 static inline void sock_orphan(struct sock *sk)
1904 write_lock_bh(&sk->sk_callback_lock);
1905 sock_set_flag(sk, SOCK_DEAD);
1906 sk_set_socket(sk, NULL);
1908 write_unlock_bh(&sk->sk_callback_lock);
1911 static inline void sock_graft(struct sock *sk, struct socket *parent)
1913 WARN_ON(parent->sk);
1914 write_lock_bh(&sk->sk_callback_lock);
1915 rcu_assign_pointer(sk->sk_wq, &parent->wq);
1917 sk_set_socket(sk, parent);
1918 sk->sk_uid = SOCK_INODE(parent)->i_uid;
1919 security_sock_graft(sk, parent);
1920 write_unlock_bh(&sk->sk_callback_lock);
1923 kuid_t sock_i_uid(struct sock *sk);
1924 unsigned long sock_i_ino(struct sock *sk);
1926 static inline kuid_t sock_net_uid(const struct net *net, const struct sock *sk)
1928 return sk ? sk->sk_uid : make_kuid(net->user_ns, 0);
1931 static inline u32 net_tx_rndhash(void)
1933 u32 v = prandom_u32();
1938 static inline void sk_set_txhash(struct sock *sk)
1940 /* This pairs with READ_ONCE() in skb_set_hash_from_sk() */
1941 WRITE_ONCE(sk->sk_txhash, net_tx_rndhash());
1944 static inline bool sk_rethink_txhash(struct sock *sk)
1946 if (sk->sk_txhash) {
1953 static inline struct dst_entry *
1954 __sk_dst_get(struct sock *sk)
1956 return rcu_dereference_check(sk->sk_dst_cache,
1957 lockdep_sock_is_held(sk));
1960 static inline struct dst_entry *
1961 sk_dst_get(struct sock *sk)
1963 struct dst_entry *dst;
1966 dst = rcu_dereference(sk->sk_dst_cache);
1967 if (dst && !atomic_inc_not_zero(&dst->__refcnt))
1973 static inline void __dst_negative_advice(struct sock *sk)
1975 struct dst_entry *ndst, *dst = __sk_dst_get(sk);
1977 if (dst && dst->ops->negative_advice) {
1978 ndst = dst->ops->negative_advice(dst);
1981 rcu_assign_pointer(sk->sk_dst_cache, ndst);
1982 sk_tx_queue_clear(sk);
1983 sk->sk_dst_pending_confirm = 0;
1988 static inline void dst_negative_advice(struct sock *sk)
1990 sk_rethink_txhash(sk);
1991 __dst_negative_advice(sk);
1995 __sk_dst_set(struct sock *sk, struct dst_entry *dst)
1997 struct dst_entry *old_dst;
1999 sk_tx_queue_clear(sk);
2000 sk->sk_dst_pending_confirm = 0;
2001 old_dst = rcu_dereference_protected(sk->sk_dst_cache,
2002 lockdep_sock_is_held(sk));
2003 rcu_assign_pointer(sk->sk_dst_cache, dst);
2004 dst_release(old_dst);
2008 sk_dst_set(struct sock *sk, struct dst_entry *dst)
2010 struct dst_entry *old_dst;
2012 sk_tx_queue_clear(sk);
2013 sk->sk_dst_pending_confirm = 0;
2014 old_dst = xchg((__force struct dst_entry **)&sk->sk_dst_cache, dst);
2015 dst_release(old_dst);
2019 __sk_dst_reset(struct sock *sk)
2021 __sk_dst_set(sk, NULL);
2025 sk_dst_reset(struct sock *sk)
2027 sk_dst_set(sk, NULL);
2030 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
2032 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
2034 static inline void sk_dst_confirm(struct sock *sk)
2036 if (!READ_ONCE(sk->sk_dst_pending_confirm))
2037 WRITE_ONCE(sk->sk_dst_pending_confirm, 1);
2040 static inline void sock_confirm_neigh(struct sk_buff *skb, struct neighbour *n)
2042 if (skb_get_dst_pending_confirm(skb)) {
2043 struct sock *sk = skb->sk;
2044 unsigned long now = jiffies;
2046 /* avoid dirtying neighbour */
2047 if (READ_ONCE(n->confirmed) != now)
2048 WRITE_ONCE(n->confirmed, now);
2049 if (sk && READ_ONCE(sk->sk_dst_pending_confirm))
2050 WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2054 bool sk_mc_loop(struct sock *sk);
2056 static inline bool sk_can_gso(const struct sock *sk)
2058 return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type);
2061 void sk_setup_caps(struct sock *sk, struct dst_entry *dst);
2063 static inline void sk_nocaps_add(struct sock *sk, netdev_features_t flags)
2065 sk->sk_route_nocaps |= flags;
2066 sk->sk_route_caps &= ~flags;
2069 static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
2070 struct iov_iter *from, char *to,
2071 int copy, int offset)
2073 if (skb->ip_summed == CHECKSUM_NONE) {
2075 if (!csum_and_copy_from_iter_full(to, copy, &csum, from))
2077 skb->csum = csum_block_add(skb->csum, csum, offset);
2078 } else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
2079 if (!copy_from_iter_full_nocache(to, copy, from))
2081 } else if (!copy_from_iter_full(to, copy, from))
2087 static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
2088 struct iov_iter *from, int copy)
2090 int err, offset = skb->len;
2092 err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy),
2095 __skb_trim(skb, offset);
2100 static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from,
2101 struct sk_buff *skb,
2107 err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off,
2113 skb->data_len += copy;
2114 skb->truesize += copy;
2115 sk_wmem_queued_add(sk, copy);
2116 sk_mem_charge(sk, copy);
2121 * sk_wmem_alloc_get - returns write allocations
2124 * Return: sk_wmem_alloc minus initial offset of one
2126 static inline int sk_wmem_alloc_get(const struct sock *sk)
2128 return refcount_read(&sk->sk_wmem_alloc) - 1;
2132 * sk_rmem_alloc_get - returns read allocations
2135 * Return: sk_rmem_alloc
2137 static inline int sk_rmem_alloc_get(const struct sock *sk)
2139 return atomic_read(&sk->sk_rmem_alloc);
2143 * sk_has_allocations - check if allocations are outstanding
2146 * Return: true if socket has write or read allocations
2148 static inline bool sk_has_allocations(const struct sock *sk)
2150 return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk);
2154 * skwq_has_sleeper - check if there are any waiting processes
2155 * @wq: struct socket_wq
2157 * Return: true if socket_wq has waiting processes
2159 * The purpose of the skwq_has_sleeper and sock_poll_wait is to wrap the memory
2160 * barrier call. They were added due to the race found within the tcp code.
2162 * Consider following tcp code paths::
2165 * sys_select receive packet
2167 * __add_wait_queue update tp->rcv_nxt
2169 * tp->rcv_nxt check sock_def_readable
2171 * schedule rcu_read_lock();
2172 * wq = rcu_dereference(sk->sk_wq);
2173 * if (wq && waitqueue_active(&wq->wait))
2174 * wake_up_interruptible(&wq->wait)
2178 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
2179 * in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1
2180 * could then endup calling schedule and sleep forever if there are no more
2181 * data on the socket.
2184 static inline bool skwq_has_sleeper(struct socket_wq *wq)
2186 return wq && wq_has_sleeper(&wq->wait);
2190 * sock_poll_wait - place memory barrier behind the poll_wait call.
2192 * @sock: socket to wait on
2195 * See the comments in the wq_has_sleeper function.
2197 static inline void sock_poll_wait(struct file *filp, struct socket *sock,
2200 if (!poll_does_not_wait(p)) {
2201 poll_wait(filp, &sock->wq.wait, p);
2202 /* We need to be sure we are in sync with the
2203 * socket flags modification.
2205 * This memory barrier is paired in the wq_has_sleeper.
2211 static inline void skb_set_hash_from_sk(struct sk_buff *skb, struct sock *sk)
2213 /* This pairs with WRITE_ONCE() in sk_set_txhash() */
2214 u32 txhash = READ_ONCE(sk->sk_txhash);
2222 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk);
2225 * Queue a received datagram if it will fit. Stream and sequenced
2226 * protocols can't normally use this as they need to fit buffers in
2227 * and play with them.
2229 * Inlined as it's very short and called for pretty much every
2230 * packet ever received.
2232 static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
2236 skb->destructor = sock_rfree;
2237 atomic_add(skb->truesize, &sk->sk_rmem_alloc);
2238 sk_mem_charge(sk, skb->truesize);
2241 static inline __must_check bool skb_set_owner_sk_safe(struct sk_buff *skb, struct sock *sk)
2243 if (sk && refcount_inc_not_zero(&sk->sk_refcnt)) {
2245 skb->destructor = sock_efree;
2252 void sk_reset_timer(struct sock *sk, struct timer_list *timer,
2253 unsigned long expires);
2255 void sk_stop_timer(struct sock *sk, struct timer_list *timer);
2257 void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer);
2259 int __sk_queue_drop_skb(struct sock *sk, struct sk_buff_head *sk_queue,
2260 struct sk_buff *skb, unsigned int flags,
2261 void (*destructor)(struct sock *sk,
2262 struct sk_buff *skb));
2263 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
2264 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
2266 int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
2267 struct sk_buff *sock_dequeue_err_skb(struct sock *sk);
2270 * Recover an error report and clear atomically
2273 static inline int sock_error(struct sock *sk)
2277 /* Avoid an atomic operation for the common case.
2278 * This is racy since another cpu/thread can change sk_err under us.
2280 if (likely(data_race(!sk->sk_err)))
2283 err = xchg(&sk->sk_err, 0);
2287 void sk_error_report(struct sock *sk);
2289 static inline unsigned long sock_wspace(struct sock *sk)
2293 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
2294 amt = sk->sk_sndbuf - refcount_read(&sk->sk_wmem_alloc);
2302 * We use sk->sk_wq_raw, from contexts knowing this
2303 * pointer is not NULL and cannot disappear/change.
2305 static inline void sk_set_bit(int nr, struct sock *sk)
2307 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2308 !sock_flag(sk, SOCK_FASYNC))
2311 set_bit(nr, &sk->sk_wq_raw->flags);
2314 static inline void sk_clear_bit(int nr, struct sock *sk)
2316 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2317 !sock_flag(sk, SOCK_FASYNC))
2320 clear_bit(nr, &sk->sk_wq_raw->flags);
2323 static inline void sk_wake_async(const struct sock *sk, int how, int band)
2325 if (sock_flag(sk, SOCK_FASYNC)) {
2327 sock_wake_async(rcu_dereference(sk->sk_wq), how, band);
2332 /* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might
2333 * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak.
2334 * Note: for send buffers, TCP works better if we can build two skbs at
2337 #define TCP_SKB_MIN_TRUESIZE (2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff)))
2339 #define SOCK_MIN_SNDBUF (TCP_SKB_MIN_TRUESIZE * 2)
2340 #define SOCK_MIN_RCVBUF TCP_SKB_MIN_TRUESIZE
2342 static inline void sk_stream_moderate_sndbuf(struct sock *sk)
2346 if (sk->sk_userlocks & SOCK_SNDBUF_LOCK)
2349 val = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
2351 WRITE_ONCE(sk->sk_sndbuf, max_t(u32, val, SOCK_MIN_SNDBUF));
2354 struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp,
2355 bool force_schedule);
2358 * sk_page_frag - return an appropriate page_frag
2361 * Use the per task page_frag instead of the per socket one for
2362 * optimization when we know that we're in the normal context and owns
2363 * everything that's associated with %current.
2365 * gfpflags_allow_blocking() isn't enough here as direct reclaim may nest
2366 * inside other socket operations and end up recursing into sk_page_frag()
2367 * while it's already in use.
2369 * Return: a per task page_frag if context allows that,
2370 * otherwise a per socket one.
2372 static inline struct page_frag *sk_page_frag(struct sock *sk)
2374 if (gfpflags_normal_context(sk->sk_allocation))
2375 return ¤t->task_frag;
2377 return &sk->sk_frag;
2380 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag);
2383 * Default write policy as shown to user space via poll/select/SIGIO
2385 static inline bool sock_writeable(const struct sock *sk)
2387 return refcount_read(&sk->sk_wmem_alloc) < (READ_ONCE(sk->sk_sndbuf) >> 1);
2390 static inline gfp_t gfp_any(void)
2392 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2395 static inline long sock_rcvtimeo(const struct sock *sk, bool noblock)
2397 return noblock ? 0 : sk->sk_rcvtimeo;
2400 static inline long sock_sndtimeo(const struct sock *sk, bool noblock)
2402 return noblock ? 0 : sk->sk_sndtimeo;
2405 static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
2407 int v = waitall ? len : min_t(int, READ_ONCE(sk->sk_rcvlowat), len);
2412 /* Alas, with timeout socket operations are not restartable.
2413 * Compare this to poll().
2415 static inline int sock_intr_errno(long timeo)
2417 return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
2420 struct sock_skb_cb {
2424 /* Store sock_skb_cb at the end of skb->cb[] so protocol families
2425 * using skb->cb[] would keep using it directly and utilize its
2426 * alignement guarantee.
2428 #define SOCK_SKB_CB_OFFSET ((sizeof_field(struct sk_buff, cb) - \
2429 sizeof(struct sock_skb_cb)))
2431 #define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \
2432 SOCK_SKB_CB_OFFSET))
2434 #define sock_skb_cb_check_size(size) \
2435 BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET)
2438 sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb)
2440 SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, SOCK_RXQ_OVFL) ?
2441 atomic_read(&sk->sk_drops) : 0;
2444 static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb)
2446 int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs);
2448 atomic_add(segs, &sk->sk_drops);
2451 static inline ktime_t sock_read_timestamp(struct sock *sk)
2453 #if BITS_PER_LONG==32
2458 seq = read_seqbegin(&sk->sk_stamp_seq);
2460 } while (read_seqretry(&sk->sk_stamp_seq, seq));
2464 return READ_ONCE(sk->sk_stamp);
2468 static inline void sock_write_timestamp(struct sock *sk, ktime_t kt)
2470 #if BITS_PER_LONG==32
2471 write_seqlock(&sk->sk_stamp_seq);
2473 write_sequnlock(&sk->sk_stamp_seq);
2475 WRITE_ONCE(sk->sk_stamp, kt);
2479 void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
2480 struct sk_buff *skb);
2481 void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
2482 struct sk_buff *skb);
2485 sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
2487 ktime_t kt = skb->tstamp;
2488 struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
2491 * generate control messages if
2492 * - receive time stamping in software requested
2493 * - software time stamp available and wanted
2494 * - hardware time stamps available and wanted
2496 if (sock_flag(sk, SOCK_RCVTSTAMP) ||
2497 (sk->sk_tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) ||
2498 (kt && sk->sk_tsflags & SOF_TIMESTAMPING_SOFTWARE) ||
2499 (hwtstamps->hwtstamp &&
2500 (sk->sk_tsflags & SOF_TIMESTAMPING_RAW_HARDWARE)))
2501 __sock_recv_timestamp(msg, sk, skb);
2503 sock_write_timestamp(sk, kt);
2505 if (sock_flag(sk, SOCK_WIFI_STATUS) && skb->wifi_acked_valid)
2506 __sock_recv_wifi_status(msg, sk, skb);
2509 void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2510 struct sk_buff *skb);
2512 #define SK_DEFAULT_STAMP (-1L * NSEC_PER_SEC)
2513 static inline void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2514 struct sk_buff *skb)
2516 #define FLAGS_TS_OR_DROPS ((1UL << SOCK_RXQ_OVFL) | \
2517 (1UL << SOCK_RCVTSTAMP))
2518 #define TSFLAGS_ANY (SOF_TIMESTAMPING_SOFTWARE | \
2519 SOF_TIMESTAMPING_RAW_HARDWARE)
2521 if (sk->sk_flags & FLAGS_TS_OR_DROPS || sk->sk_tsflags & TSFLAGS_ANY)
2522 __sock_recv_ts_and_drops(msg, sk, skb);
2523 else if (unlikely(sock_flag(sk, SOCK_TIMESTAMP)))
2524 sock_write_timestamp(sk, skb->tstamp);
2525 else if (unlikely(sk->sk_stamp == SK_DEFAULT_STAMP))
2526 sock_write_timestamp(sk, 0);
2529 void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags);
2532 * _sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
2533 * @sk: socket sending this packet
2534 * @tsflags: timestamping flags to use
2535 * @tx_flags: completed with instructions for time stamping
2536 * @tskey: filled in with next sk_tskey (not for TCP, which uses seqno)
2538 * Note: callers should take care of initial ``*tx_flags`` value (usually 0)
2540 static inline void _sock_tx_timestamp(struct sock *sk, __u16 tsflags,
2541 __u8 *tx_flags, __u32 *tskey)
2543 if (unlikely(tsflags)) {
2544 __sock_tx_timestamp(tsflags, tx_flags);
2545 if (tsflags & SOF_TIMESTAMPING_OPT_ID && tskey &&
2546 tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK)
2547 *tskey = sk->sk_tskey++;
2549 if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS)))
2550 *tx_flags |= SKBTX_WIFI_STATUS;
2553 static inline void sock_tx_timestamp(struct sock *sk, __u16 tsflags,
2556 _sock_tx_timestamp(sk, tsflags, tx_flags, NULL);
2559 static inline void skb_setup_tx_timestamp(struct sk_buff *skb, __u16 tsflags)
2561 _sock_tx_timestamp(skb->sk, tsflags, &skb_shinfo(skb)->tx_flags,
2562 &skb_shinfo(skb)->tskey);
2565 DECLARE_STATIC_KEY_FALSE(tcp_rx_skb_cache_key);
2567 * sk_eat_skb - Release a skb if it is no longer needed
2568 * @sk: socket to eat this skb from
2569 * @skb: socket buffer to eat
2571 * This routine must be called with interrupts disabled or with the socket
2572 * locked so that the sk_buff queue operation is ok.
2574 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb)
2576 __skb_unlink(skb, &sk->sk_receive_queue);
2577 if (static_branch_unlikely(&tcp_rx_skb_cache_key) &&
2578 !sk->sk_rx_skb_cache) {
2579 sk->sk_rx_skb_cache = skb;
2587 struct net *sock_net(const struct sock *sk)
2589 return read_pnet(&sk->sk_net);
2593 void sock_net_set(struct sock *sk, struct net *net)
2595 write_pnet(&sk->sk_net, net);
2599 skb_sk_is_prefetched(struct sk_buff *skb)
2602 return skb->destructor == sock_pfree;
2605 #endif /* CONFIG_INET */
2608 /* This helper checks if a socket is a full socket,
2609 * ie _not_ a timewait or request socket.
2611 static inline bool sk_fullsock(const struct sock *sk)
2613 return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV);
2617 sk_is_refcounted(struct sock *sk)
2619 /* Only full sockets have sk->sk_flags. */
2620 return !sk_fullsock(sk) || !sock_flag(sk, SOCK_RCU_FREE);
2624 * skb_steal_sock - steal a socket from an sk_buff
2625 * @skb: sk_buff to steal the socket from
2626 * @refcounted: is set to true if the socket is reference-counted
2628 static inline struct sock *
2629 skb_steal_sock(struct sk_buff *skb, bool *refcounted)
2632 struct sock *sk = skb->sk;
2635 if (skb_sk_is_prefetched(skb))
2636 *refcounted = sk_is_refcounted(sk);
2637 skb->destructor = NULL;
2641 *refcounted = false;
2645 /* Checks if this SKB belongs to an HW offloaded socket
2646 * and whether any SW fallbacks are required based on dev.
2647 * Check decrypted mark in case skb_orphan() cleared socket.
2649 static inline struct sk_buff *sk_validate_xmit_skb(struct sk_buff *skb,
2650 struct net_device *dev)
2652 #ifdef CONFIG_SOCK_VALIDATE_XMIT
2653 struct sock *sk = skb->sk;
2655 if (sk && sk_fullsock(sk) && sk->sk_validate_xmit_skb) {
2656 skb = sk->sk_validate_xmit_skb(sk, dev, skb);
2657 #ifdef CONFIG_TLS_DEVICE
2658 } else if (unlikely(skb->decrypted)) {
2659 pr_warn_ratelimited("unencrypted skb with no associated socket - dropping\n");
2669 /* This helper checks if a socket is a LISTEN or NEW_SYN_RECV
2670 * SYNACK messages can be attached to either ones (depending on SYNCOOKIE)
2672 static inline bool sk_listener(const struct sock *sk)
2674 return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV);
2677 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag);
2678 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level,
2681 bool sk_ns_capable(const struct sock *sk,
2682 struct user_namespace *user_ns, int cap);
2683 bool sk_capable(const struct sock *sk, int cap);
2684 bool sk_net_capable(const struct sock *sk, int cap);
2686 void sk_get_meminfo(const struct sock *sk, u32 *meminfo);
2688 /* Take into consideration the size of the struct sk_buff overhead in the
2689 * determination of these values, since that is non-constant across
2690 * platforms. This makes socket queueing behavior and performance
2691 * not depend upon such differences.
2693 #define _SK_MEM_PACKETS 256
2694 #define _SK_MEM_OVERHEAD SKB_TRUESIZE(256)
2695 #define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2696 #define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2698 extern __u32 sysctl_wmem_max;
2699 extern __u32 sysctl_rmem_max;
2701 extern int sysctl_tstamp_allow_data;
2702 extern int sysctl_optmem_max;
2704 extern __u32 sysctl_wmem_default;
2705 extern __u32 sysctl_rmem_default;
2707 DECLARE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
2709 static inline int sk_get_wmem0(const struct sock *sk, const struct proto *proto)
2711 /* Does this proto have per netns sysctl_wmem ? */
2712 if (proto->sysctl_wmem_offset)
2713 return *(int *)((void *)sock_net(sk) + proto->sysctl_wmem_offset);
2715 return *proto->sysctl_wmem;
2718 static inline int sk_get_rmem0(const struct sock *sk, const struct proto *proto)
2720 /* Does this proto have per netns sysctl_rmem ? */
2721 if (proto->sysctl_rmem_offset)
2722 return *(int *)((void *)sock_net(sk) + proto->sysctl_rmem_offset);
2724 return *proto->sysctl_rmem;
2727 /* Default TCP Small queue budget is ~1 ms of data (1sec >> 10)
2728 * Some wifi drivers need to tweak it to get more chunks.
2729 * They can use this helper from their ndo_start_xmit()
2731 static inline void sk_pacing_shift_update(struct sock *sk, int val)
2733 if (!sk || !sk_fullsock(sk) || READ_ONCE(sk->sk_pacing_shift) == val)
2735 WRITE_ONCE(sk->sk_pacing_shift, val);
2738 /* if a socket is bound to a device, check that the given device
2739 * index is either the same or that the socket is bound to an L3
2740 * master device and the given device index is also enslaved to
2743 static inline bool sk_dev_equal_l3scope(struct sock *sk, int dif)
2747 if (!sk->sk_bound_dev_if || sk->sk_bound_dev_if == dif)
2750 mdif = l3mdev_master_ifindex_by_index(sock_net(sk), dif);
2751 if (mdif && mdif == sk->sk_bound_dev_if)
2757 void sock_def_readable(struct sock *sk);
2759 int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk);
2760 void sock_set_timestamp(struct sock *sk, int optname, bool valbool);
2761 int sock_set_timestamping(struct sock *sk, int optname,
2762 struct so_timestamping timestamping);
2764 void sock_enable_timestamps(struct sock *sk);
2765 void sock_no_linger(struct sock *sk);
2766 void sock_set_keepalive(struct sock *sk);
2767 void sock_set_priority(struct sock *sk, u32 priority);
2768 void sock_set_rcvbuf(struct sock *sk, int val);
2769 void sock_set_mark(struct sock *sk, u32 val);
2770 void sock_set_reuseaddr(struct sock *sk);
2771 void sock_set_reuseport(struct sock *sk);
2772 void sock_set_sndtimeo(struct sock *sk, s64 secs);
2774 int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len);
2776 #endif /* _SOCK_H */