1	/* SPDX-License-Identifier: GPL-2.0-or-later */
2	/*
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.
6	*
7	* Definitions for the AF_INET socket handler.
8	*
9	* Version: @(#)sock.h 1.0.4 05/13/93
10	*
11	* Authors: Ross Biro
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>
15	*
16	* Fixes:
17	* Alan Cox : Volatiles in skbuff pointers. See
18	* skbuff comments. May be overdone,
19	* better to prove they can be removed
20	* than the reverse.
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
34	*/
35	#ifndef _SOCK_H
36	#define _SOCK_H
37
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 */
48	#include <linux/mm.h>
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/rculist_nulls.h>
60	#include <linux/poll.h>
61	#include <linux/sockptr.h>
62	#include <linux/indirect_call_wrapper.h>
63	#include <linux/atomic.h>
64	#include <linux/refcount.h>
65	#include <linux/llist.h>
66	#include <net/dst.h>
67	#include <net/checksum.h>
68	#include <net/tcp_states.h>
69	#include <linux/net_tstamp.h>
70	#include <net/l3mdev.h>
71	#include <uapi/linux/socket.h>
72
73	/*
74	* This structure really needs to be cleaned up.
75	* Most of it is for TCP, and not used by any of
76	* the other protocols.
77	*/
78
79	/* This is the per-socket lock. The spinlock provides a synchronization
80	* between user contexts and software interrupt processing, whereas the
81	* mini-semaphore synchronizes multiple users amongst themselves.
82	*/
83	typedef struct {
84	spinlock_t slock;
85	int owned;
86	wait_queue_head_t wq;
87	/*
88	* We express the mutex-alike socket_lock semantics
89	* to the lock validator by explicitly managing
90	* the slock as a lock variant (in addition to
91	* the slock itself):
92	*/
93	#ifdef CONFIG_DEBUG_LOCK_ALLOC
94	struct lockdep_map dep_map;
95	#endif
96	} socket_lock_t;
97
98	struct sock;
99	struct proto;
100	struct net;
101
102	typedef __u32 __bitwise __portpair;
103	typedef __u64 __bitwise __addrpair;
104
105	/**
106	* struct sock_common - minimal network layer representation of sockets
107	* @skc_daddr: Foreign IPv4 addr
108	* @skc_rcv_saddr: Bound local IPv4 addr
109	* @skc_addrpair: 8-byte-aligned __u64 union of @skc_daddr & @skc_rcv_saddr
110	* @skc_hash: hash value used with various protocol lookup tables
111	* @skc_u16hashes: two u16 hash values used by UDP lookup tables
112	* @skc_dport: placeholder for inet_dport/tw_dport
113	* @skc_num: placeholder for inet_num/tw_num
114	* @skc_portpair: __u32 union of @skc_dport & @skc_num
115	* @skc_family: network address family
116	* @skc_state: Connection state
117	* @skc_reuse: %SO_REUSEADDR setting
118	* @skc_reuseport: %SO_REUSEPORT setting
119	* @skc_ipv6only: socket is IPV6 only
120	* @skc_net_refcnt: socket is using net ref counting
121	* @skc_bound_dev_if: bound device index if != 0
122	* @skc_bind_node: bind hash linkage for various protocol lookup tables
123	* @skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol
124	* @skc_prot: protocol handlers inside a network family
125	* @skc_net: reference to the network namespace of this socket
126	* @skc_v6_daddr: IPV6 destination address
127	* @skc_v6_rcv_saddr: IPV6 source address
128	* @skc_cookie: socket's cookie value
129	* @skc_node: main hash linkage for various protocol lookup tables
130	* @skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol
131	* @skc_tx_queue_mapping: tx queue number for this connection
132	* @skc_rx_queue_mapping: rx queue number for this connection
133	* @skc_flags: place holder for sk_flags
134	* %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE,
135	* %SO_OOBINLINE settings, %SO_TIMESTAMPING settings
136	* @skc_listener: connection request listener socket (aka rsk_listener)
137	* [union with @skc_flags]
138	* @skc_tw_dr: (aka tw_dr) ptr to &struct inet_timewait_death_row
139	* [union with @skc_flags]
140	* @skc_incoming_cpu: record/match cpu processing incoming packets
141	* @skc_rcv_wnd: (aka rsk_rcv_wnd) TCP receive window size (possibly scaled)
142	* [union with @skc_incoming_cpu]
143	* @skc_tw_rcv_nxt: (aka tw_rcv_nxt) TCP window next expected seq number
144	* [union with @skc_incoming_cpu]
145	* @skc_refcnt: reference count
146	*
147	* This is the minimal network layer representation of sockets, the header
148	* for struct sock and struct inet_timewait_sock.
149	*/
150	struct sock_common {
151	union {
152	__addrpair skc_addrpair;
153	struct {
154	__be32 skc_daddr;
155	__be32 skc_rcv_saddr;
156	};
157	};
158	union {
159	unsigned int skc_hash;
160	__u16 skc_u16hashes[2];
161	};
162	/* skc_dport && skc_num must be grouped as well */
163	union {
164	__portpair skc_portpair;
165	struct {
166	__be16 skc_dport;
167	__u16 skc_num;
168	};
169	};
170
171	unsigned short skc_family;
172	volatile unsigned char skc_state;
173	unsigned char skc_reuse:4;
174	unsigned char skc_reuseport:1;
175	unsigned char skc_ipv6only:1;
176	unsigned char skc_net_refcnt:1;
177	int skc_bound_dev_if;
178	union {
179	struct hlist_node skc_bind_node;
180	struct hlist_node skc_portaddr_node;
181	};
182	struct proto *skc_prot;
183	possible_net_t skc_net;
184
185	#if IS_ENABLED(CONFIG_IPV6)
186	struct in6_addr skc_v6_daddr;
187	struct in6_addr skc_v6_rcv_saddr;
188	#endif
189
190	atomic64_t skc_cookie;
191
192	/* following fields are padding to force
193	* offset(struct sock, sk_refcnt) == 128 on 64bit arches
194	* assuming IPV6 is enabled. We use this padding differently
195	* for different kind of 'sockets'
196	*/
197	union {
198	unsigned long skc_flags;
199	struct sock *skc_listener; /* request_sock */
200	struct inet_timewait_death_row *skc_tw_dr; /* inet_timewait_sock */
201	};
202	/*
203	* fields between dontcopy_begin/dontcopy_end
204	* are not copied in sock_copy()
205	*/
206	/* private: */
207	int skc_dontcopy_begin[0];
208	/* public: */
209	union {
210	struct hlist_node skc_node;
211	struct hlist_nulls_node skc_nulls_node;
212	};
213	unsigned short skc_tx_queue_mapping;
214	#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
215	unsigned short skc_rx_queue_mapping;
216	#endif
217	union {
218	int skc_incoming_cpu;
219	u32 skc_rcv_wnd;
220	u32 skc_tw_rcv_nxt; /* struct tcp_timewait_sock */
221	};
222
223	refcount_t skc_refcnt;
224	/* private: */
225	int skc_dontcopy_end[0];
226	union {
227	u32 skc_rxhash;
228	u32 skc_window_clamp;
229	u32 skc_tw_snd_nxt; /* struct tcp_timewait_sock */
230	};
231	/* public: */
232	};
233
234	struct bpf_local_storage;
235	struct sk_filter;
236
237	/**
238	* struct sock - network layer representation of sockets
239	* @__sk_common: shared layout with inet_timewait_sock
240	* @sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
241	* @sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
242	* @sk_lock: synchronizer
243	* @sk_kern_sock: True if sock is using kernel lock classes
244	* @sk_rcvbuf: size of receive buffer in bytes
245	* @sk_wq: sock wait queue and async head
246	* @sk_rx_dst: receive input route used by early demux
247	* @sk_rx_dst_ifindex: ifindex for @sk_rx_dst
248	* @sk_rx_dst_cookie: cookie for @sk_rx_dst
249	* @sk_dst_cache: destination cache
250	* @sk_dst_pending_confirm: need to confirm neighbour
251	* @sk_policy: flow policy
252	* @sk_receive_queue: incoming packets
253	* @sk_wmem_alloc: transmit queue bytes committed
254	* @sk_tsq_flags: TCP Small Queues flags
255	* @sk_write_queue: Packet sending queue
256	* @sk_omem_alloc: "o" is "option" or "other"
257	* @sk_wmem_queued: persistent queue size
258	* @sk_forward_alloc: space allocated forward
259	* @sk_reserved_mem: space reserved and non-reclaimable for the socket
260	* @sk_napi_id: id of the last napi context to receive data for sk
261	* @sk_ll_usec: usecs to busypoll when there is no data
262	* @sk_allocation: allocation mode
263	* @sk_pacing_rate: Pacing rate (if supported by transport/packet scheduler)
264	* @sk_pacing_status: Pacing status (requested, handled by sch_fq)
265	* @sk_max_pacing_rate: Maximum pacing rate (%SO_MAX_PACING_RATE)
266	* @sk_sndbuf: size of send buffer in bytes
267	* @sk_no_check_tx: %SO_NO_CHECK setting, set checksum in TX packets
268	* @sk_no_check_rx: allow zero checksum in RX packets
269	* @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
270	* @sk_gso_disabled: if set, NETIF_F_GSO_MASK is forbidden.
271	* @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
272	* @sk_gso_max_size: Maximum GSO segment size to build
273	* @sk_gso_max_segs: Maximum number of GSO segments
274	* @sk_pacing_shift: scaling factor for TCP Small Queues
275	* @sk_lingertime: %SO_LINGER l_linger setting
276	* @sk_backlog: always used with the per-socket spinlock held
277	* @sk_callback_lock: used with the callbacks in the end of this struct
278	* @sk_error_queue: rarely used
279	* @sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt,
280	* IPV6_ADDRFORM for instance)
281	* @sk_err: last error
282	* @sk_err_soft: errors that don't cause failure but are the cause of a
283	* persistent failure not just 'timed out'
284	* @sk_drops: raw/udp drops counter
285	* @sk_ack_backlog: current listen backlog
286	* @sk_max_ack_backlog: listen backlog set in listen()
287	* @sk_uid: user id of owner
288	* @sk_prefer_busy_poll: prefer busypolling over softirq processing
289	* @sk_busy_poll_budget: napi processing budget when busypolling
290	* @sk_priority: %SO_PRIORITY setting
291	* @sk_type: socket type (%SOCK_STREAM, etc)
292	* @sk_protocol: which protocol this socket belongs in this network family
293	* @sk_peer_lock: lock protecting @sk_peer_pid and @sk_peer_cred
294	* @sk_peer_pid: &struct pid for this socket's peer
295	* @sk_peer_cred: %SO_PEERCRED setting
296	* @sk_rcvlowat: %SO_RCVLOWAT setting
297	* @sk_rcvtimeo: %SO_RCVTIMEO setting
298	* @sk_sndtimeo: %SO_SNDTIMEO setting
299	* @sk_txhash: computed flow hash for use on transmit
300	* @sk_txrehash: enable TX hash rethink
301	* @sk_filter: socket filtering instructions
302	* @sk_timer: sock cleanup timer
303	* @sk_stamp: time stamp of last packet received
304	* @sk_stamp_seq: lock for accessing sk_stamp on 32 bit architectures only
305	* @sk_tsflags: SO_TIMESTAMPING flags
306	* @sk_use_task_frag: allow sk_page_frag() to use current->task_frag.
307	* Sockets that can be used under memory reclaim should
308	* set this to false.
309	* @sk_bind_phc: SO_TIMESTAMPING bind PHC index of PTP virtual clock
310	* for timestamping
311	* @sk_tskey: counter to disambiguate concurrent tstamp requests
312	* @sk_zckey: counter to order MSG_ZEROCOPY notifications
313	* @sk_socket: Identd and reporting IO signals
314	* @sk_user_data: RPC layer private data. Write-protected by @sk_callback_lock.
315	* @sk_frag: cached page frag
316	* @sk_peek_off: current peek_offset value
317	* @sk_send_head: front of stuff to transmit
318	* @tcp_rtx_queue: TCP re-transmit queue [union with @sk_send_head]
319	* @sk_security: used by security modules
320	* @sk_mark: generic packet mark
321	* @sk_cgrp_data: cgroup data for this cgroup
322	* @sk_memcg: this socket's memory cgroup association
323	* @sk_write_pending: a write to stream socket waits to start
324	* @sk_disconnects: number of disconnect operations performed on this sock
325	* @sk_state_change: callback to indicate change in the state of the sock
326	* @sk_data_ready: callback to indicate there is data to be processed
327	* @sk_write_space: callback to indicate there is bf sending space available
328	* @sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
329	* @sk_backlog_rcv: callback to process the backlog
330	* @sk_validate_xmit_skb: ptr to an optional validate function
331	* @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
332	* @sk_reuseport_cb: reuseport group container
333	* @sk_bpf_storage: ptr to cache and control for bpf_sk_storage
334	* @sk_rcu: used during RCU grace period
335	* @sk_clockid: clockid used by time-based scheduling (SO_TXTIME)
336	* @sk_txtime_deadline_mode: set deadline mode for SO_TXTIME
337	* @sk_txtime_report_errors: set report errors mode for SO_TXTIME
338	* @sk_txtime_unused: unused txtime flags
339	* @ns_tracker: tracker for netns reference
340	*/
341	struct sock {
342	/*
343	* Now struct inet_timewait_sock also uses sock_common, so please just
344	* don't add nothing before this first member (__sk_common) --acme
345	*/
346	struct sock_common __sk_common;
347	#define sk_node __sk_common.skc_node
348	#define sk_nulls_node __sk_common.skc_nulls_node
349	#define sk_refcnt __sk_common.skc_refcnt
350	#define sk_tx_queue_mapping __sk_common.skc_tx_queue_mapping
351	#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
352	#define sk_rx_queue_mapping __sk_common.skc_rx_queue_mapping
353	#endif
354
355	#define sk_dontcopy_begin __sk_common.skc_dontcopy_begin
356	#define sk_dontcopy_end __sk_common.skc_dontcopy_end
357	#define sk_hash __sk_common.skc_hash
358	#define sk_portpair __sk_common.skc_portpair
359	#define sk_num __sk_common.skc_num
360	#define sk_dport __sk_common.skc_dport
361	#define sk_addrpair __sk_common.skc_addrpair
362	#define sk_daddr __sk_common.skc_daddr
363	#define sk_rcv_saddr __sk_common.skc_rcv_saddr
364	#define sk_family __sk_common.skc_family
365	#define sk_state __sk_common.skc_state
366	#define sk_reuse __sk_common.skc_reuse
367	#define sk_reuseport __sk_common.skc_reuseport
368	#define sk_ipv6only __sk_common.skc_ipv6only
369	#define sk_net_refcnt __sk_common.skc_net_refcnt
370	#define sk_bound_dev_if __sk_common.skc_bound_dev_if
371	#define sk_bind_node __sk_common.skc_bind_node
372	#define sk_prot __sk_common.skc_prot
373	#define sk_net __sk_common.skc_net
374	#define sk_v6_daddr __sk_common.skc_v6_daddr
375	#define sk_v6_rcv_saddr __sk_common.skc_v6_rcv_saddr
376	#define sk_cookie __sk_common.skc_cookie
377	#define sk_incoming_cpu __sk_common.skc_incoming_cpu
378	#define sk_flags __sk_common.skc_flags
379	#define sk_rxhash __sk_common.skc_rxhash
380
381	__cacheline_group_begin(sock_write_rx);
382
383	atomic_t sk_drops;
384	__s32 sk_peek_off;
385	struct sk_buff_head sk_error_queue;
386	struct sk_buff_head sk_receive_queue;
387	/*
388	* The backlog queue is special, it is always used with
389	* the per-socket spinlock held and requires low latency
390	* access. Therefore we special case it's implementation.
391	* Note : rmem_alloc is in this structure to fill a hole
392	* on 64bit arches, not because its logically part of
393	* backlog.
394	*/
395	struct {
396	atomic_t rmem_alloc;
397	int len;
398	struct sk_buff *head;
399	struct sk_buff *tail;
400	} sk_backlog;
401	#define sk_rmem_alloc sk_backlog.rmem_alloc
402
403	__cacheline_group_end(sock_write_rx);
404
405	__cacheline_group_begin(sock_read_rx);
406	/* early demux fields */
407	struct dst_entry __rcu *sk_rx_dst;
408	int sk_rx_dst_ifindex;
409	u32 sk_rx_dst_cookie;
410
411	#ifdef CONFIG_NET_RX_BUSY_POLL
412	unsigned int sk_ll_usec;
413	unsigned int sk_napi_id;
414	u16 sk_busy_poll_budget;
415	u8 sk_prefer_busy_poll;
416	#endif
417	u8 sk_userlocks;
418	int sk_rcvbuf;
419
420	struct sk_filter __rcu *sk_filter;
421	union {
422	struct socket_wq __rcu *sk_wq;
423	/* private: */
424	struct socket_wq *sk_wq_raw;
425	/* public: */
426	};
427
428	void (*sk_data_ready)(struct sock *sk);
429	long sk_rcvtimeo;
430	int sk_rcvlowat;
431	__cacheline_group_end(sock_read_rx);
432
433	__cacheline_group_begin(sock_read_rxtx);
434	int sk_err;
435	struct socket *sk_socket;
436	struct mem_cgroup *sk_memcg;
437	#ifdef CONFIG_XFRM
438	struct xfrm_policy __rcu *sk_policy[2];
439	#endif
440	__cacheline_group_end(sock_read_rxtx);
441
442	__cacheline_group_begin(sock_write_rxtx);
443	socket_lock_t sk_lock;
444	u32 sk_reserved_mem;
445	int sk_forward_alloc;
446	u32 sk_tsflags;
447	__cacheline_group_end(sock_write_rxtx);
448
449	__cacheline_group_begin(sock_write_tx);
450	int sk_write_pending;
451	atomic_t sk_omem_alloc;
452	int sk_sndbuf;
453
454	int sk_wmem_queued;
455	refcount_t sk_wmem_alloc;
456	unsigned long sk_tsq_flags;
457	union {
458	struct sk_buff *sk_send_head;
459	struct rb_root tcp_rtx_queue;
460	};
461	struct sk_buff_head sk_write_queue;
462	u32 sk_dst_pending_confirm;
463	u32 sk_pacing_status; /* see enum sk_pacing */
464	struct page_frag sk_frag;
465	struct timer_list sk_timer;
466
467	unsigned long sk_pacing_rate; /* bytes per second */
468	atomic_t sk_zckey;
469	atomic_t sk_tskey;
470	__cacheline_group_end(sock_write_tx);
471
472	__cacheline_group_begin(sock_read_tx);
473	unsigned long sk_max_pacing_rate;
474	long sk_sndtimeo;
475	u32 sk_priority;
476	u32 sk_mark;
477	struct dst_entry __rcu *sk_dst_cache;
478	netdev_features_t sk_route_caps;
479	#ifdef CONFIG_SOCK_VALIDATE_XMIT
480	struct sk_buff* (*sk_validate_xmit_skb)(struct sock *sk,
481	struct net_device *dev,
482	struct sk_buff *skb);
483	#endif
484	u16 sk_gso_type;
485	u16 sk_gso_max_segs;
486	unsigned int sk_gso_max_size;
487	gfp_t sk_allocation;
488	u32 sk_txhash;
489	u8 sk_pacing_shift;
490	bool sk_use_task_frag;
491	__cacheline_group_end(sock_read_tx);
492
493	/*
494	* Because of non atomicity rules, all
495	* changes are protected by socket lock.
496	*/
497	u8 sk_gso_disabled : 1,
498	sk_kern_sock : 1,
499	sk_no_check_tx : 1,
500	sk_no_check_rx : 1;
501	u8 sk_shutdown;
502	u16 sk_type;
503	u16 sk_protocol;
504	unsigned long sk_lingertime;
505	struct proto *sk_prot_creator;
506	rwlock_t sk_callback_lock;
507	int sk_err_soft;
508	u32 sk_ack_backlog;
509	u32 sk_max_ack_backlog;
510	kuid_t sk_uid;
511	spinlock_t sk_peer_lock;
512	int sk_bind_phc;
513	struct pid *sk_peer_pid;
514	const struct cred *sk_peer_cred;
515
516	ktime_t sk_stamp;
517	#if BITS_PER_LONG==32
518	seqlock_t sk_stamp_seq;
519	#endif
520	int sk_disconnects;
521
522	u8 sk_txrehash;
523	u8 sk_clockid;
524	u8 sk_txtime_deadline_mode : 1,
525	sk_txtime_report_errors : 1,
526	sk_txtime_unused : 6;
527
528	void *sk_user_data;
529	#ifdef CONFIG_SECURITY
530	void *sk_security;
531	#endif
532	struct sock_cgroup_data sk_cgrp_data;
533	void (*sk_state_change)(struct sock *sk);
534	void (*sk_write_space)(struct sock *sk);
535	void (*sk_error_report)(struct sock *sk);
536	int (*sk_backlog_rcv)(struct sock *sk,
537	struct sk_buff *skb);
538	void (*sk_destruct)(struct sock *sk);
539	struct sock_reuseport __rcu *sk_reuseport_cb;
540	#ifdef CONFIG_BPF_SYSCALL
541	struct bpf_local_storage __rcu *sk_bpf_storage;
542	#endif
543	struct rcu_head sk_rcu;
544	netns_tracker ns_tracker;
545	};
546
547	enum sk_pacing {
548	SK_PACING_NONE = 0,
549	SK_PACING_NEEDED = 1,
550	SK_PACING_FQ = 2,
551	};
552
553	/* flag bits in sk_user_data
554	*
555	* - SK_USER_DATA_NOCOPY: Pointer stored in sk_user_data might
556	* not be suitable for copying when cloning the socket. For instance,
557	* it can point to a reference counted object. sk_user_data bottom
558	* bit is set if pointer must not be copied.
559	*
560	* - SK_USER_DATA_BPF: Mark whether sk_user_data field is
561	* managed/owned by a BPF reuseport array. This bit should be set
562	* when sk_user_data's sk is added to the bpf's reuseport_array.
563	*
564	* - SK_USER_DATA_PSOCK: Mark whether pointer stored in
565	* sk_user_data points to psock type. This bit should be set
566	* when sk_user_data is assigned to a psock object.
567	*/
568	#define SK_USER_DATA_NOCOPY 1UL
569	#define SK_USER_DATA_BPF 2UL
570	#define SK_USER_DATA_PSOCK 4UL
571	#define SK_USER_DATA_PTRMASK ~(SK_USER_DATA_NOCOPY | SK_USER_DATA_BPF |\
572	SK_USER_DATA_PSOCK)
573
574	/**
575	* sk_user_data_is_nocopy - Test if sk_user_data pointer must not be copied
576	* @sk: socket
577	*/
578	static inline bool sk_user_data_is_nocopy(const struct sock *sk)
579	{
580	return ((uintptr_t)sk->sk_user_data & SK_USER_DATA_NOCOPY);
581	}
582
583	#define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data)))
584
585	/**
586	* __locked_read_sk_user_data_with_flags - return the pointer
587	* only if argument flags all has been set in sk_user_data. Otherwise
588	* return NULL
589	*
590	* @sk: socket
591	* @flags: flag bits
592	*
593	* The caller must be holding sk->sk_callback_lock.
594	*/
595	static inline void *
596	__locked_read_sk_user_data_with_flags(const struct sock *sk,
597	uintptr_t flags)
598	{
599	uintptr_t sk_user_data =
600	(uintptr_t)rcu_dereference_check(__sk_user_data(sk),
601	lockdep_is_held(&sk->sk_callback_lock));
602
603	WARN_ON_ONCE(flags & SK_USER_DATA_PTRMASK);
604
605	if ((sk_user_data & flags) == flags)
606	return (void *)(sk_user_data & SK_USER_DATA_PTRMASK);
607	return NULL;
608	}
609
610	/**
611	* __rcu_dereference_sk_user_data_with_flags - return the pointer
612	* only if argument flags all has been set in sk_user_data. Otherwise
613	* return NULL
614	*
615	* @sk: socket
616	* @flags: flag bits
617	*/
618	static inline void *
619	__rcu_dereference_sk_user_data_with_flags(const struct sock *sk,
620	uintptr_t flags)
621	{
622	uintptr_t sk_user_data = (uintptr_t)rcu_dereference(__sk_user_data(sk));
623
624	WARN_ON_ONCE(flags & SK_USER_DATA_PTRMASK);
625
626	if ((sk_user_data & flags) == flags)
627	return (void *)(sk_user_data & SK_USER_DATA_PTRMASK);
628	return NULL;
629	}
630
631	#define rcu_dereference_sk_user_data(sk) \
632	__rcu_dereference_sk_user_data_with_flags(sk, 0)
633	#define __rcu_assign_sk_user_data_with_flags(sk, ptr, flags) \
634	({ \
635	uintptr_t __tmp1 = (uintptr_t)(ptr), \
636	__tmp2 = (uintptr_t)(flags); \
637	WARN_ON_ONCE(__tmp1 & ~SK_USER_DATA_PTRMASK); \
638	WARN_ON_ONCE(__tmp2 & SK_USER_DATA_PTRMASK); \
639	rcu_assign_pointer(__sk_user_data((sk)), \
640	__tmp1 | __tmp2); \
641	})
642	#define rcu_assign_sk_user_data(sk, ptr) \
643	__rcu_assign_sk_user_data_with_flags(sk, ptr, 0)
644
645	static inline
646	struct net *sock_net(const struct sock *sk)
647	{
648	return read_pnet(pnet: &sk->sk_net);
649	}
650
651	static inline
652	void sock_net_set(struct sock *sk, struct net *net)
653	{
654	write_pnet(pnet: &sk->sk_net, net);
655	}
656
657	/*
658	* SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK
659	* or not whether his port will be reused by someone else. SK_FORCE_REUSE
660	* on a socket means that the socket will reuse everybody else's port
661	* without looking at the other's sk_reuse value.
662	*/
663
664	#define SK_NO_REUSE 0
665	#define SK_CAN_REUSE 1
666	#define SK_FORCE_REUSE 2
667
668	int sk_set_peek_off(struct sock *sk, int val);
669
670	static inline int sk_peek_offset(const struct sock *sk, int flags)
671	{
672	if (unlikely(flags & MSG_PEEK)) {
673	return READ_ONCE(sk->sk_peek_off);
674	}
675
676	return 0;
677	}
678
679	static inline void sk_peek_offset_bwd(struct sock *sk, int val)
680	{
681	s32 off = READ_ONCE(sk->sk_peek_off);
682
683	if (unlikely(off >= 0)) {
684	off = max_t(s32, off - val, 0);
685	WRITE_ONCE(sk->sk_peek_off, off);
686	}
687	}
688
689	static inline void sk_peek_offset_fwd(struct sock *sk, int val)
690	{
691	sk_peek_offset_bwd(sk, val: -val);
692	}
693
694	/*
695	* Hashed lists helper routines
696	*/
697	static inline struct sock *sk_entry(const struct hlist_node *node)
698	{
699	return hlist_entry(node, struct sock, sk_node);
700	}
701
702	static inline struct sock *__sk_head(const struct hlist_head *head)
703	{
704	return hlist_entry(head->first, struct sock, sk_node);
705	}
706
707	static inline struct sock *sk_head(const struct hlist_head *head)
708	{
709	return hlist_empty(h: head) ? NULL : __sk_head(head);
710	}
711
712	static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head)
713	{
714	return hlist_nulls_entry(head->first, struct sock, sk_nulls_node);
715	}
716
717	static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head)
718	{
719	return hlist_nulls_empty(h: head) ? NULL : __sk_nulls_head(head);
720	}
721
722	static inline struct sock *sk_next(const struct sock *sk)
723	{
724	return hlist_entry_safe(sk->sk_node.next, struct sock, sk_node);
725	}
726
727	static inline struct sock *sk_nulls_next(const struct sock *sk)
728	{
729	return (!is_a_nulls(ptr: sk->sk_nulls_node.next)) ?
730	hlist_nulls_entry(sk->sk_nulls_node.next,
731	struct sock, sk_nulls_node) :
732	NULL;
733	}
734
735	static inline bool sk_unhashed(const struct sock *sk)
736	{
737	return hlist_unhashed(h: &sk->sk_node);
738	}
739
740	static inline bool sk_hashed(const struct sock *sk)
741	{
742	return !sk_unhashed(sk);
743	}
744
745	static inline void sk_node_init(struct hlist_node *node)
746	{
747	node->pprev = NULL;
748	}
749
750	static inline void __sk_del_node(struct sock *sk)
751	{
752	__hlist_del(n: &sk->sk_node);
753	}
754
755	/* NB: equivalent to hlist_del_init_rcu */
756	static inline bool __sk_del_node_init(struct sock *sk)
757	{
758	if (sk_hashed(sk)) {
759	__sk_del_node(sk);
760	sk_node_init(node: &sk->sk_node);
761	return true;
762	}
763	return false;
764	}
765
766	/* Grab socket reference count. This operation is valid only
767	when sk is ALREADY grabbed f.e. it is found in hash table
768	or a list and the lookup is made under lock preventing hash table
769	modifications.
770	*/
771
772	static __always_inline void sock_hold(struct sock *sk)
773	{
774	refcount_inc(r: &sk->sk_refcnt);
775	}
776
777	/* Ungrab socket in the context, which assumes that socket refcnt
778	cannot hit zero, f.e. it is true in context of any socketcall.
779	*/
780	static __always_inline void __sock_put(struct sock *sk)
781	{
782	refcount_dec(r: &sk->sk_refcnt);
783	}
784
785	static inline bool sk_del_node_init(struct sock *sk)
786	{
787	bool rc = __sk_del_node_init(sk);
788
789	if (rc) {
790	/* paranoid for a while -acme */
791	WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
792	__sock_put(sk);
793	}
794	return rc;
795	}
796	#define sk_del_node_init_rcu(sk) sk_del_node_init(sk)
797
798	static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk)
799	{
800	if (sk_hashed(sk)) {
801	hlist_nulls_del_init_rcu(n: &sk->sk_nulls_node);
802	return true;
803	}
804	return false;
805	}
806
807	static inline bool sk_nulls_del_node_init_rcu(struct sock *sk)
808	{
809	bool rc = __sk_nulls_del_node_init_rcu(sk);
810
811	if (rc) {
812	/* paranoid for a while -acme */
813	WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
814	__sock_put(sk);
815	}
816	return rc;
817	}
818
819	static inline void __sk_add_node(struct sock *sk, struct hlist_head *list)
820	{
821	hlist_add_head(n: &sk->sk_node, h: list);
822	}
823
824	static inline void sk_add_node(struct sock *sk, struct hlist_head *list)
825	{
826	sock_hold(sk);
827	__sk_add_node(sk, list);
828	}
829
830	static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list)
831	{
832	sock_hold(sk);
833	if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport &&
834	sk->sk_family == AF_INET6)
835	hlist_add_tail_rcu(n: &sk->sk_node, h: list);
836	else
837	hlist_add_head_rcu(n: &sk->sk_node, h: list);
838	}
839
840	static inline void sk_add_node_tail_rcu(struct sock *sk, struct hlist_head *list)
841	{
842	sock_hold(sk);
843	hlist_add_tail_rcu(n: &sk->sk_node, h: list);
844	}
845
846	static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
847	{
848	hlist_nulls_add_head_rcu(n: &sk->sk_nulls_node, h: list);
849	}
850
851	static inline void __sk_nulls_add_node_tail_rcu(struct sock *sk, struct hlist_nulls_head *list)
852	{
853	hlist_nulls_add_tail_rcu(n: &sk->sk_nulls_node, h: list);
854	}
855
856	static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
857	{
858	sock_hold(sk);
859	__sk_nulls_add_node_rcu(sk, list);
860	}
861
862	static inline void __sk_del_bind_node(struct sock *sk)
863	{
864	__hlist_del(n: &sk->sk_bind_node);
865	}
866
867	static inline void sk_add_bind_node(struct sock *sk,
868	struct hlist_head *list)
869	{
870	hlist_add_head(n: &sk->sk_bind_node, h: list);
871	}
872
873	#define sk_for_each(__sk, list) \
874	hlist_for_each_entry(__sk, list, sk_node)
875	#define sk_for_each_rcu(__sk, list) \
876	hlist_for_each_entry_rcu(__sk, list, sk_node)
877	#define sk_nulls_for_each(__sk, node, list) \
878	hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)
879	#define sk_nulls_for_each_rcu(__sk, node, list) \
880	hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)
881	#define sk_for_each_from(__sk) \
882	hlist_for_each_entry_from(__sk, sk_node)
883	#define sk_nulls_for_each_from(__sk, node) \
884	if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \
885	hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node)
886	#define sk_for_each_safe(__sk, tmp, list) \
887	hlist_for_each_entry_safe(__sk, tmp, list, sk_node)
888	#define sk_for_each_bound(__sk, list) \
889	hlist_for_each_entry(__sk, list, sk_bind_node)
890
891	/**
892	* sk_for_each_entry_offset_rcu - iterate over a list at a given struct offset
893	* @tpos: the type * to use as a loop cursor.
894	* @pos: the &struct hlist_node to use as a loop cursor.
895	* @head: the head for your list.
896	* @offset: offset of hlist_node within the struct.
897	*
898	*/
899	#define sk_for_each_entry_offset_rcu(tpos, pos, head, offset) \
900	for (pos = rcu_dereference(hlist_first_rcu(head)); \
901	pos != NULL && \
902	({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;}); \
903	pos = rcu_dereference(hlist_next_rcu(pos)))
904
905	static inline struct user_namespace *sk_user_ns(const struct sock *sk)
906	{
907	/* Careful only use this in a context where these parameters
908	* can not change and must all be valid, such as recvmsg from
909	* userspace.
910	*/
911	return sk->sk_socket->file->f_cred->user_ns;
912	}
913
914	/* Sock flags */
915	enum sock_flags {
916	SOCK_DEAD,
917	SOCK_DONE,
918	SOCK_URGINLINE,
919	SOCK_KEEPOPEN,
920	SOCK_LINGER,
921	SOCK_DESTROY,
922	SOCK_BROADCAST,
923	SOCK_TIMESTAMP,
924	SOCK_ZAPPED,
925	SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */
926	SOCK_DBG, /* %SO_DEBUG setting */
927	SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
928	SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */
929	SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
930	SOCK_MEMALLOC, /* VM depends on this socket for swapping */
931	SOCK_TIMESTAMPING_RX_SOFTWARE, /* %SOF_TIMESTAMPING_RX_SOFTWARE */
932	SOCK_FASYNC, /* fasync() active */
933	SOCK_RXQ_OVFL,
934	SOCK_ZEROCOPY, /* buffers from userspace */
935	SOCK_WIFI_STATUS, /* push wifi status to userspace */
936	SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS.
937	* Will use last 4 bytes of packet sent from
938	* user-space instead.
939	*/
940	SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */
941	SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */
942	SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */
943	SOCK_TXTIME,
944	SOCK_XDP, /* XDP is attached */
945	SOCK_TSTAMP_NEW, /* Indicates 64 bit timestamps always */
946	SOCK_RCVMARK, /* Receive SO_MARK ancillary data with packet */
947	};
948
949	#define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))
950
951	static inline void sock_copy_flags(struct sock *nsk, const struct sock *osk)
952	{
953	nsk->sk_flags = osk->sk_flags;
954	}
955
956	static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
957	{
958	__set_bit(flag, &sk->sk_flags);
959	}
960
961	static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag)
962	{
963	__clear_bit(flag, &sk->sk_flags);
964	}
965
966	static inline void sock_valbool_flag(struct sock *sk, enum sock_flags bit,
967	int valbool)
968	{
969	if (valbool)
970	sock_set_flag(sk, flag: bit);
971	else
972	sock_reset_flag(sk, flag: bit);
973	}
974
975	static inline bool sock_flag(const struct sock *sk, enum sock_flags flag)
976	{
977	return test_bit(flag, &sk->sk_flags);
978	}
979
980	#ifdef CONFIG_NET
981	DECLARE_STATIC_KEY_FALSE(memalloc_socks_key);
982	static inline int sk_memalloc_socks(void)
983	{
984	return static_branch_unlikely(&memalloc_socks_key);
985	}
986
987	void __receive_sock(struct file *file);
988	#else
989
990	static inline int sk_memalloc_socks(void)
991	{
992	return 0;
993	}
994
995	static inline void __receive_sock(struct file *file)
996	{ }
997	#endif
998
999	static inline gfp_t sk_gfp_mask(const struct sock *sk, gfp_t gfp_mask)
1000	{
1001	return gfp_mask | (sk->sk_allocation & __GFP_MEMALLOC);
1002	}
1003
1004	static inline void sk_acceptq_removed(struct sock *sk)
1005	{
1006	WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog - 1);
1007	}
1008
1009	static inline void sk_acceptq_added(struct sock *sk)
1010	{
1011	WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog + 1);
1012	}
1013
1014	/* Note: If you think the test should be:
1015	* return READ_ONCE(sk->sk_ack_backlog) >= READ_ONCE(sk->sk_max_ack_backlog);
1016	* Then please take a look at commit 64a146513f8f ("[NET]: Revert incorrect accept queue backlog changes.")
1017	*/
1018	static inline bool sk_acceptq_is_full(const struct sock *sk)
1019	{
1020	return READ_ONCE(sk->sk_ack_backlog) > READ_ONCE(sk->sk_max_ack_backlog);
1021	}
1022
1023	/*
1024	* Compute minimal free write space needed to queue new packets.
1025	*/
1026	static inline int sk_stream_min_wspace(const struct sock *sk)
1027	{
1028	return READ_ONCE(sk->sk_wmem_queued) >> 1;
1029	}
1030
1031	static inline int sk_stream_wspace(const struct sock *sk)
1032	{
1033	return READ_ONCE(sk->sk_sndbuf) - READ_ONCE(sk->sk_wmem_queued);
1034	}
1035
1036	static inline void sk_wmem_queued_add(struct sock *sk, int val)
1037	{
1038	WRITE_ONCE(sk->sk_wmem_queued, sk->sk_wmem_queued + val);
1039	}
1040
1041	static inline void sk_forward_alloc_add(struct sock *sk, int val)
1042	{
1043	/* Paired with lockless reads of sk->sk_forward_alloc */
1044	WRITE_ONCE(sk->sk_forward_alloc, sk->sk_forward_alloc + val);
1045	}
1046
1047	void sk_stream_write_space(struct sock *sk);
1048
1049	/* OOB backlog add */
1050	static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
1051	{
1052	/* dont let skb dst not refcounted, we are going to leave rcu lock */
1053	skb_dst_force(skb);
1054
1055	if (!sk->sk_backlog.tail)
1056	WRITE_ONCE(sk->sk_backlog.head, skb);
1057	else
1058	sk->sk_backlog.tail->next = skb;
1059
1060	WRITE_ONCE(sk->sk_backlog.tail, skb);
1061	skb->next = NULL;
1062	}
1063
1064	/*
1065	* Take into account size of receive queue and backlog queue
1066	* Do not take into account this skb truesize,
1067	* to allow even a single big packet to come.
1068	*/
1069	static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit)
1070	{
1071	unsigned int qsize = sk->sk_backlog.len + atomic_read(v: &sk->sk_rmem_alloc);
1072
1073	return qsize > limit;
1074	}
1075
1076	/* The per-socket spinlock must be held here. */
1077	static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb,
1078	unsigned int limit)
1079	{
1080	if (sk_rcvqueues_full(sk, limit))
1081	return -ENOBUFS;
1082
1083	/*
1084	* If the skb was allocated from pfmemalloc reserves, only
1085	* allow SOCK_MEMALLOC sockets to use it as this socket is
1086	* helping free memory
1087	*/
1088	if (skb_pfmemalloc(skb) && !sock_flag(sk, flag: SOCK_MEMALLOC))
1089	return -ENOMEM;
1090
1091	__sk_add_backlog(sk, skb);
1092	sk->sk_backlog.len += skb->truesize;
1093	return 0;
1094	}
1095
1096	int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb);
1097
1098	INDIRECT_CALLABLE_DECLARE(int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb));
1099	INDIRECT_CALLABLE_DECLARE(int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb));
1100
1101	static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
1102	{
1103	if (sk_memalloc_socks() && skb_pfmemalloc(skb))
1104	return __sk_backlog_rcv(sk, skb);
1105
1106	return INDIRECT_CALL_INET(sk->sk_backlog_rcv,
1107	tcp_v6_do_rcv,
1108	tcp_v4_do_rcv,
1109	sk, skb);
1110	}
1111
1112	static inline void sk_incoming_cpu_update(struct sock *sk)
1113	{
1114	int cpu = raw_smp_processor_id();
1115
1116	if (unlikely(READ_ONCE(sk->sk_incoming_cpu) != cpu))
1117	WRITE_ONCE(sk->sk_incoming_cpu, cpu);
1118	}
1119
1120
1121	static inline void sock_rps_save_rxhash(struct sock *sk,
1122	const struct sk_buff *skb)
1123	{
1124	#ifdef CONFIG_RPS
1125	/* The following WRITE_ONCE() is paired with the READ_ONCE()
1126	* here, and another one in sock_rps_record_flow().
1127	*/
1128	if (unlikely(READ_ONCE(sk->sk_rxhash) != skb->hash))
1129	WRITE_ONCE(sk->sk_rxhash, skb->hash);
1130	#endif
1131	}
1132
1133	static inline void sock_rps_reset_rxhash(struct sock *sk)
1134	{
1135	#ifdef CONFIG_RPS
1136	/* Paired with READ_ONCE() in sock_rps_record_flow() */
1137	WRITE_ONCE(sk->sk_rxhash, 0);
1138	#endif
1139	}
1140
1141	#define sk_wait_event(__sk, __timeo, __condition, __wait) \
1142	({ int __rc, __dis = __sk->sk_disconnects; \
1143	release_sock(__sk); \
1144	__rc = __condition; \
1145	if (!__rc) { \
1146	*(__timeo) = wait_woken(__wait, \
1147	TASK_INTERRUPTIBLE, \
1148	*(__timeo)); \
1149	} \
1150	sched_annotate_sleep(); \
1151	lock_sock(__sk); \
1152	__rc = __dis == __sk->sk_disconnects ? __condition : -EPIPE; \
1153	__rc; \
1154	})
1155
1156	int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
1157	int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
1158	void sk_stream_wait_close(struct sock *sk, long timeo_p);
1159	int sk_stream_error(struct sock *sk, int flags, int err);
1160	void sk_stream_kill_queues(struct sock *sk);
1161	void sk_set_memalloc(struct sock *sk);
1162	void sk_clear_memalloc(struct sock *sk);
1163
1164	void __sk_flush_backlog(struct sock *sk);
1165
1166	static inline bool sk_flush_backlog(struct sock *sk)
1167	{
1168	if (unlikely(READ_ONCE(sk->sk_backlog.tail))) {
1169	__sk_flush_backlog(sk);
1170	return true;
1171	}
1172	return false;
1173	}
1174
1175	int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb);
1176
1177	struct request_sock_ops;
1178	struct timewait_sock_ops;
1179	struct inet_hashinfo;
1180	struct raw_hashinfo;
1181	struct smc_hashinfo;
1182	struct module;
1183	struct sk_psock;
1184
1185	/*
1186	* caches using SLAB_TYPESAFE_BY_RCU should let .next pointer from nulls nodes
1187	* un-modified. Special care is taken when initializing object to zero.
1188	*/
1189	static inline void sk_prot_clear_nulls(struct sock *sk, int size)
1190	{
1191	if (offsetof(struct sock, sk_node.next) != 0)
1192	memset(sk, 0, offsetof(struct sock, sk_node.next));
1193	memset(&sk->sk_node.pprev, 0,
1194	size - offsetof(struct sock, sk_node.pprev));
1195	}
1196
1197	/* Networking protocol blocks we attach to sockets.
1198	* socket layer -> transport layer interface
1199	*/
1200	struct proto {
1201	void (*close)(struct sock *sk,
1202	long timeout);
1203	int (*pre_connect)(struct sock *sk,
1204	struct sockaddr *uaddr,
1205	int addr_len);
1206	int (*connect)(struct sock *sk,
1207	struct sockaddr *uaddr,
1208	int addr_len);
1209	int (*disconnect)(struct sock *sk, int flags);
1210
1211	struct sock * (*accept)(struct sock *sk, int flags, int *err,
1212	bool kern);
1213
1214	int (*ioctl)(struct sock *sk, int cmd,
1215	int *karg);
1216	int (*init)(struct sock *sk);
1217	void (*destroy)(struct sock *sk);
1218	void (*shutdown)(struct sock *sk, int how);
1219	int (*setsockopt)(struct sock *sk, int level,
1220	int optname, sockptr_t optval,
1221	unsigned int optlen);
1222	int (*getsockopt)(struct sock *sk, int level,
1223	int optname, char __user *optval,
1224	int __user *option);
1225	void (*keepalive)(struct sock *sk, int valbool);
1226	#ifdef CONFIG_COMPAT
1227	int (*compat_ioctl)(struct sock *sk,
1228	unsigned int cmd, unsigned long arg);
1229	#endif
1230	int (*sendmsg)(struct sock *sk, struct msghdr *msg,
1231	size_t len);
1232	int (*recvmsg)(struct sock *sk, struct msghdr *msg,
1233	size_t len, int flags, int *addr_len);
1234	void (*splice_eof)(struct socket *sock);
1235	int (*bind)(struct sock *sk,
1236	struct sockaddr *addr, int addr_len);
1237	int (*bind_add)(struct sock *sk,
1238	struct sockaddr *addr, int addr_len);
1239
1240	int (*backlog_rcv) (struct sock *sk,
1241	struct sk_buff *skb);
1242	bool (*bpf_bypass_getsockopt)(int level,
1243	int optname);
1244
1245	void (*release_cb)(struct sock *sk);
1246
1247	/* Keeping track of sk's, looking them up, and port selection methods. */
1248	int (*hash)(struct sock *sk);
1249	void (*unhash)(struct sock *sk);
1250	void (*rehash)(struct sock *sk);
1251	int (*get_port)(struct sock *sk, unsigned short snum);
1252	void (*put_port)(struct sock *sk);
1253	#ifdef CONFIG_BPF_SYSCALL
1254	int (*psock_update_sk_prot)(struct sock *sk,
1255	struct sk_psock *psock,
1256	bool restore);
1257	#endif
1258
1259	/* Keeping track of sockets in use */
1260	#ifdef CONFIG_PROC_FS
1261	unsigned int inuse_idx;
1262	#endif
1263
1264	#if IS_ENABLED(CONFIG_MPTCP)
1265	int (*forward_alloc_get)(const struct sock *sk);
1266	#endif
1267
1268	bool (*stream_memory_free)(const struct sock *sk, int wake);
1269	bool (*sock_is_readable)(struct sock *sk);
1270	/* Memory pressure */
1271	void (*enter_memory_pressure)(struct sock *sk);
1272	void (*leave_memory_pressure)(struct sock *sk);
1273	atomic_long_t *memory_allocated; /* Current allocated memory. */
1274	int __percpu *per_cpu_fw_alloc;
1275	struct percpu_counter *sockets_allocated; /* Current number of sockets. */
1276
1277	/*
1278	* Pressure flag: try to collapse.
1279	* Technical note: it is used by multiple contexts non atomically.
1280	* Make sure to use READ_ONCE()/WRITE_ONCE() for all reads/writes.
1281	* All the __sk_mem_schedule() is of this nature: accounting
1282	* is strict, actions are advisory and have some latency.
1283	*/
1284	unsigned long *memory_pressure;
1285	long *sysctl_mem;
1286
1287	int *sysctl_wmem;
1288	int *sysctl_rmem;
1289	u32 sysctl_wmem_offset;
1290	u32 sysctl_rmem_offset;
1291
1292	int max_header;
1293	bool no_autobind;
1294
1295	struct kmem_cache *slab;
1296	unsigned int obj_size;
1297	unsigned int ipv6_pinfo_offset;
1298	slab_flags_t slab_flags;
1299	unsigned int useroffset; /* Usercopy region offset */
1300	unsigned int usersize; /* Usercopy region size */
1301
1302	unsigned int __percpu *orphan_count;
1303
1304	struct request_sock_ops *rsk_prot;
1305	struct timewait_sock_ops *twsk_prot;
1306
1307	union {
1308	struct inet_hashinfo *hashinfo;
1309	struct udp_table *udp_table;
1310	struct raw_hashinfo *raw_hash;
1311	struct smc_hashinfo *smc_hash;
1312	} h;
1313
1314	struct module *owner;
1315
1316	char name[32];
1317
1318	struct list_head node;
1319	int (*diag_destroy)(struct sock *sk, int err);
1320	} __randomize_layout;
1321
1322	int proto_register(struct proto *prot, int alloc_slab);
1323	void proto_unregister(struct proto *prot);
1324	int sock_load_diag_module(int family, int protocol);
1325
1326	INDIRECT_CALLABLE_DECLARE(bool tcp_stream_memory_free(const struct sock *sk, int wake));
1327
1328	static inline int sk_forward_alloc_get(const struct sock *sk)
1329	{
1330	#if IS_ENABLED(CONFIG_MPTCP)
1331	if (sk->sk_prot->forward_alloc_get)
1332	return sk->sk_prot->forward_alloc_get(sk);
1333	#endif
1334	return READ_ONCE(sk->sk_forward_alloc);
1335	}
1336
1337	static inline bool __sk_stream_memory_free(const struct sock *sk, int wake)
1338	{
1339	if (READ_ONCE(sk->sk_wmem_queued) >= READ_ONCE(sk->sk_sndbuf))
1340	return false;
1341
1342	return sk->sk_prot->stream_memory_free ?
1343	INDIRECT_CALL_INET_1(sk->sk_prot->stream_memory_free,
1344	tcp_stream_memory_free, sk, wake) : true;
1345	}
1346
1347	static inline bool sk_stream_memory_free(const struct sock *sk)
1348	{
1349	return __sk_stream_memory_free(sk, wake: 0);
1350	}
1351
1352	static inline bool __sk_stream_is_writeable(const struct sock *sk, int wake)
1353	{
1354	return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) &&
1355	__sk_stream_memory_free(sk, wake);
1356	}
1357
1358	static inline bool sk_stream_is_writeable(const struct sock *sk)
1359	{
1360	return __sk_stream_is_writeable(sk, wake: 0);
1361	}
1362
1363	static inline int sk_under_cgroup_hierarchy(struct sock *sk,
1364	struct cgroup *ancestor)
1365	{
1366	#ifdef CONFIG_SOCK_CGROUP_DATA
1367	return cgroup_is_descendant(cgrp: sock_cgroup_ptr(skcd: &sk->sk_cgrp_data),
1368	ancestor);
1369	#else
1370	return -ENOTSUPP;
1371	#endif
1372	}
1373
1374	static inline bool sk_has_memory_pressure(const struct sock *sk)
1375	{
1376	return sk->sk_prot->memory_pressure != NULL;
1377	}
1378
1379	static inline bool sk_under_global_memory_pressure(const struct sock *sk)
1380	{
1381	return sk->sk_prot->memory_pressure &&
1382	!!READ_ONCE(*sk->sk_prot->memory_pressure);
1383	}
1384
1385	static inline bool sk_under_memory_pressure(const struct sock *sk)
1386	{
1387	if (!sk->sk_prot->memory_pressure)
1388	return false;
1389
1390	if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
1391	mem_cgroup_under_socket_pressure(memcg: sk->sk_memcg))
1392	return true;
1393
1394	return !!READ_ONCE(*sk->sk_prot->memory_pressure);
1395	}
1396
1397	static inline long
1398	proto_memory_allocated(const struct proto *prot)
1399	{
1400	return max(0L, atomic_long_read(prot->memory_allocated));
1401	}
1402
1403	static inline long
1404	sk_memory_allocated(const struct sock *sk)
1405	{
1406	return proto_memory_allocated(prot: sk->sk_prot);
1407	}
1408
1409	/* 1 MB per cpu, in page units */
1410	#define SK_MEMORY_PCPU_RESERVE (1 << (20 - PAGE_SHIFT))
1411	extern int sysctl_mem_pcpu_rsv;
1412
1413	static inline void
1414	sk_memory_allocated_add(struct sock *sk, int amt)
1415	{
1416	int local_reserve;
1417
1418	preempt_disable();
1419	local_reserve = __this_cpu_add_return(*sk->sk_prot->per_cpu_fw_alloc, amt);
1420	if (local_reserve >= READ_ONCE(sysctl_mem_pcpu_rsv)) {
1421	__this_cpu_sub(*sk->sk_prot->per_cpu_fw_alloc, local_reserve);
1422	atomic_long_add(i: local_reserve, v: sk->sk_prot->memory_allocated);
1423	}
1424	preempt_enable();
1425	}
1426
1427	static inline void
1428	sk_memory_allocated_sub(struct sock *sk, int amt)
1429	{
1430	int local_reserve;
1431
1432	preempt_disable();
1433	local_reserve = __this_cpu_sub_return(*sk->sk_prot->per_cpu_fw_alloc, amt);
1434	if (local_reserve <= -READ_ONCE(sysctl_mem_pcpu_rsv)) {
1435	__this_cpu_sub(*sk->sk_prot->per_cpu_fw_alloc, local_reserve);
1436	atomic_long_add(i: local_reserve, v: sk->sk_prot->memory_allocated);
1437	}
1438	preempt_enable();
1439	}
1440
1441	#define SK_ALLOC_PERCPU_COUNTER_BATCH 16
1442
1443	static inline void sk_sockets_allocated_dec(struct sock *sk)
1444	{
1445	percpu_counter_add_batch(fbc: sk->sk_prot->sockets_allocated, amount: -1,
1446	SK_ALLOC_PERCPU_COUNTER_BATCH);
1447	}
1448
1449	static inline void sk_sockets_allocated_inc(struct sock *sk)
1450	{
1451	percpu_counter_add_batch(fbc: sk->sk_prot->sockets_allocated, amount: 1,
1452	SK_ALLOC_PERCPU_COUNTER_BATCH);
1453	}
1454
1455	static inline u64
1456	sk_sockets_allocated_read_positive(struct sock *sk)
1457	{
1458	return percpu_counter_read_positive(fbc: sk->sk_prot->sockets_allocated);
1459	}
1460
1461	static inline int
1462	proto_sockets_allocated_sum_positive(struct proto *prot)
1463	{
1464	return percpu_counter_sum_positive(fbc: prot->sockets_allocated);
1465	}
1466
1467	static inline bool
1468	proto_memory_pressure(struct proto *prot)
1469	{
1470	if (!prot->memory_pressure)
1471	return false;
1472	return !!READ_ONCE(*prot->memory_pressure);
1473	}
1474
1475
1476	#ifdef CONFIG_PROC_FS
1477	#define PROTO_INUSE_NR 64 /* should be enough for the first time */
1478	struct prot_inuse {
1479	int all;
1480	int val[PROTO_INUSE_NR];
1481	};
1482
1483	static inline void sock_prot_inuse_add(const struct net *net,
1484	const struct proto *prot, int val)
1485	{
1486	this_cpu_add(net->core.prot_inuse->val[prot->inuse_idx], val);
1487	}
1488
1489	static inline void sock_inuse_add(const struct net *net, int val)
1490	{
1491	this_cpu_add(net->core.prot_inuse->all, val);
1492	}
1493
1494	int sock_prot_inuse_get(struct net *net, struct proto *proto);
1495	int sock_inuse_get(struct net *net);
1496	#else
1497	static inline void sock_prot_inuse_add(const struct net *net,
1498	const struct proto *prot, int val)
1499	{
1500	}
1501
1502	static inline void sock_inuse_add(const struct net *net, int val)
1503	{
1504	}
1505	#endif
1506
1507
1508	/* With per-bucket locks this operation is not-atomic, so that
1509	* this version is not worse.
1510	*/
1511	static inline int __sk_prot_rehash(struct sock *sk)
1512	{
1513	sk->sk_prot->unhash(sk);
1514	return sk->sk_prot->hash(sk);
1515	}
1516
1517	/* About 10 seconds */
1518	#define SOCK_DESTROY_TIME (10*HZ)
1519
1520	/* Sockets 0-1023 can't be bound to unless you are superuser */
1521	#define PROT_SOCK 1024
1522
1523	#define SHUTDOWN_MASK 3
1524	#define RCV_SHUTDOWN 1
1525	#define SEND_SHUTDOWN 2
1526
1527	#define SOCK_BINDADDR_LOCK 4
1528	#define SOCK_BINDPORT_LOCK 8
1529
1530	struct socket_alloc {
1531	struct socket socket;
1532	struct inode vfs_inode;
1533	};
1534
1535	static inline struct socket *SOCKET_I(struct inode *inode)
1536	{
1537	return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
1538	}
1539
1540	static inline struct inode *SOCK_INODE(struct socket *socket)
1541	{
1542	return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
1543	}
1544
1545	/*
1546	* Functions for memory accounting
1547	*/
1548	int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind);
1549	int __sk_mem_schedule(struct sock *sk, int size, int kind);
1550	void __sk_mem_reduce_allocated(struct sock *sk, int amount);
1551	void __sk_mem_reclaim(struct sock *sk, int amount);
1552
1553	#define SK_MEM_SEND 0
1554	#define SK_MEM_RECV 1
1555
1556	/* sysctl_mem values are in pages */
1557	static inline long sk_prot_mem_limits(const struct sock *sk, int index)
1558	{
1559	return READ_ONCE(sk->sk_prot->sysctl_mem[index]);
1560	}
1561
1562	static inline int sk_mem_pages(int amt)
1563	{
1564	return (amt + PAGE_SIZE - 1) >> PAGE_SHIFT;
1565	}
1566
1567	static inline bool sk_has_account(struct sock *sk)
1568	{
1569	/* return true if protocol supports memory accounting */
1570	return !!sk->sk_prot->memory_allocated;
1571	}
1572
1573	static inline bool sk_wmem_schedule(struct sock *sk, int size)
1574	{
1575	int delta;
1576
1577	if (!sk_has_account(sk))
1578	return true;
1579	delta = size - sk->sk_forward_alloc;
1580	return delta <= 0 || __sk_mem_schedule(sk, size: delta, SK_MEM_SEND);
1581	}
1582
1583	static inline bool
1584	sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size)
1585	{
1586	int delta;
1587
1588	if (!sk_has_account(sk))
1589	return true;
1590	delta = size - sk->sk_forward_alloc;
1591	return delta <= 0 || __sk_mem_schedule(sk, size: delta, SK_MEM_RECV) ||
1592	skb_pfmemalloc(skb);
1593	}
1594
1595	static inline int sk_unused_reserved_mem(const struct sock *sk)
1596	{
1597	int unused_mem;
1598
1599	if (likely(!sk->sk_reserved_mem))
1600	return 0;
1601
1602	unused_mem = sk->sk_reserved_mem - sk->sk_wmem_queued -
1603	atomic_read(v: &sk->sk_rmem_alloc);
1604
1605	return unused_mem > 0 ? unused_mem : 0;
1606	}
1607
1608	static inline void sk_mem_reclaim(struct sock *sk)
1609	{
1610	int reclaimable;
1611
1612	if (!sk_has_account(sk))
1613	return;
1614
1615	reclaimable = sk->sk_forward_alloc - sk_unused_reserved_mem(sk);
1616
1617	if (reclaimable >= (int)PAGE_SIZE)
1618	__sk_mem_reclaim(sk, amount: reclaimable);
1619	}
1620
1621	static inline void sk_mem_reclaim_final(struct sock *sk)
1622	{
1623	sk->sk_reserved_mem = 0;
1624	sk_mem_reclaim(sk);
1625	}
1626
1627	static inline void sk_mem_charge(struct sock *sk, int size)
1628	{
1629	if (!sk_has_account(sk))
1630	return;
1631	sk_forward_alloc_add(sk, val: -size);
1632	}
1633
1634	static inline void sk_mem_uncharge(struct sock *sk, int size)
1635	{
1636	if (!sk_has_account(sk))
1637	return;
1638	sk_forward_alloc_add(sk, val: size);
1639	sk_mem_reclaim(sk);
1640	}
1641
1642	/*
1643	* Macro so as to not evaluate some arguments when
1644	* lockdep is not enabled.
1645	*
1646	* Mark both the sk_lock and the sk_lock.slock as a
1647	* per-address-family lock class.
1648	*/
1649	#define sock_lock_init_class_and_name(sk, sname, skey, name, key) \
1650	do { \
1651	sk->sk_lock.owned = 0; \
1652	init_waitqueue_head(&sk->sk_lock.wq); \
1653	spin_lock_init(&(sk)->sk_lock.slock); \
1654	debug_check_no_locks_freed((void *)&(sk)->sk_lock, \
1655	sizeof((sk)->sk_lock)); \
1656	lockdep_set_class_and_name(&(sk)->sk_lock.slock, \
1657	(skey), (sname)); \
1658	lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \
1659	} while (0)
1660
1661	static inline bool lockdep_sock_is_held(const struct sock *sk)
1662	{
1663	return lockdep_is_held(&sk->sk_lock) ||
1664	lockdep_is_held(&sk->sk_lock.slock);
1665	}
1666
1667	void lock_sock_nested(struct sock *sk, int subclass);
1668
1669	static inline void lock_sock(struct sock *sk)
1670	{
1671	lock_sock_nested(sk, subclass: 0);
1672	}
1673
1674	void __lock_sock(struct sock *sk);
1675	void __release_sock(struct sock *sk);
1676	void release_sock(struct sock *sk);
1677
1678	/* BH context may only use the following locking interface. */
1679	#define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock))
1680	#define bh_lock_sock_nested(__sk) \
1681	spin_lock_nested(&((__sk)->sk_lock.slock), \
1682	SINGLE_DEPTH_NESTING)
1683	#define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock))
1684
1685	bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock);
1686
1687	/**
1688	* lock_sock_fast - fast version of lock_sock
1689	* @sk: socket
1690	*
1691	* This version should be used for very small section, where process wont block
1692	* return false if fast path is taken:
1693	*
1694	* sk_lock.slock locked, owned = 0, BH disabled
1695	*
1696	* return true if slow path is taken:
1697	*
1698	* sk_lock.slock unlocked, owned = 1, BH enabled
1699	*/
1700	static inline bool lock_sock_fast(struct sock *sk)
1701	{
1702	/* The sk_lock has mutex_lock() semantics here. */
1703	mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
1704
1705	return __lock_sock_fast(sk);
1706	}
1707
1708	/* fast socket lock variant for caller already holding a [different] socket lock */
1709	static inline bool lock_sock_fast_nested(struct sock *sk)
1710	{
1711	mutex_acquire(&sk->sk_lock.dep_map, SINGLE_DEPTH_NESTING, 0, _RET_IP_);
1712
1713	return __lock_sock_fast(sk);
1714	}
1715
1716	/**
1717	* unlock_sock_fast - complement of lock_sock_fast
1718	* @sk: socket
1719	* @slow: slow mode
1720	*
1721	* fast unlock socket for user context.
1722	* If slow mode is on, we call regular release_sock()
1723	*/
1724	static inline void unlock_sock_fast(struct sock *sk, bool slow)
1725	__releases(&sk->sk_lock.slock)
1726	{
1727	if (slow) {
1728	release_sock(sk);
1729	__release(&sk->sk_lock.slock);
1730	} else {
1731	mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
1732	spin_unlock_bh(lock: &sk->sk_lock.slock);
1733	}
1734	}
1735
1736	void sockopt_lock_sock(struct sock *sk);
1737	void sockopt_release_sock(struct sock *sk);
1738	bool sockopt_ns_capable(struct user_namespace *ns, int cap);
1739	bool sockopt_capable(int cap);
1740
1741	/* Used by processes to "lock" a socket state, so that
1742	* interrupts and bottom half handlers won't change it
1743	* from under us. It essentially blocks any incoming
1744	* packets, so that we won't get any new data or any
1745	* packets that change the state of the socket.
1746	*
1747	* While locked, BH processing will add new packets to
1748	* the backlog queue. This queue is processed by the
1749	* owner of the socket lock right before it is released.
1750	*
1751	* Since ~2.3.5 it is also exclusive sleep lock serializing
1752	* accesses from user process context.
1753	*/
1754
1755	static inline void sock_owned_by_me(const struct sock *sk)
1756	{
1757	#ifdef CONFIG_LOCKDEP
1758	WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks);
1759	#endif
1760	}
1761
1762	static inline void sock_not_owned_by_me(const struct sock *sk)
1763	{
1764	#ifdef CONFIG_LOCKDEP
1765	WARN_ON_ONCE(lockdep_sock_is_held(sk) && debug_locks);
1766	#endif
1767	}
1768
1769	static inline bool sock_owned_by_user(const struct sock *sk)
1770	{
1771	sock_owned_by_me(sk);
1772	return sk->sk_lock.owned;
1773	}
1774
1775	static inline bool sock_owned_by_user_nocheck(const struct sock *sk)
1776	{
1777	return sk->sk_lock.owned;
1778	}
1779
1780	static inline void sock_release_ownership(struct sock *sk)
1781	{
1782	DEBUG_NET_WARN_ON_ONCE(!sock_owned_by_user_nocheck(sk));
1783	sk->sk_lock.owned = 0;
1784
1785	/* The sk_lock has mutex_unlock() semantics: */
1786	mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
1787	}
1788
1789	/* no reclassification while locks are held */
1790	static inline bool sock_allow_reclassification(const struct sock *csk)
1791	{
1792	struct sock *sk = (struct sock *)csk;
1793
1794	return !sock_owned_by_user_nocheck(sk) &&
1795	!spin_is_locked(lock: &sk->sk_lock.slock);
1796	}
1797
1798	struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1799	struct proto *prot, int kern);
1800	void sk_free(struct sock *sk);
1801	void sk_destruct(struct sock *sk);
1802	struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority);
1803	void sk_free_unlock_clone(struct sock *sk);
1804
1805	struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1806	gfp_t priority);
1807	void __sock_wfree(struct sk_buff *skb);
1808	void sock_wfree(struct sk_buff *skb);
1809	struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
1810	gfp_t priority);
1811	void skb_orphan_partial(struct sk_buff *skb);
1812	void sock_rfree(struct sk_buff *skb);
1813	void sock_efree(struct sk_buff *skb);
1814	#ifdef CONFIG_INET
1815	void sock_edemux(struct sk_buff *skb);
1816	void sock_pfree(struct sk_buff *skb);
1817	#else
1818	#define sock_edemux sock_efree
1819	#endif
1820
1821	int sk_setsockopt(struct sock *sk, int level, int optname,
1822	sockptr_t optval, unsigned int optlen);
1823	int sock_setsockopt(struct socket *sock, int level, int op,
1824	sockptr_t optval, unsigned int optlen);
1825	int do_sock_setsockopt(struct socket *sock, bool compat, int level,
1826	int optname, sockptr_t optval, int optlen);
1827	int do_sock_getsockopt(struct socket *sock, bool compat, int level,
1828	int optname, sockptr_t optval, sockptr_t optlen);
1829
1830	int sk_getsockopt(struct sock *sk, int level, int optname,
1831	sockptr_t optval, sockptr_t optlen);
1832	int sock_gettstamp(struct socket *sock, void __user *userstamp,
1833	bool timeval, bool time32);
1834	struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1835	unsigned long data_len, int noblock,
1836	int *errcode, int max_page_order);
1837
1838	static inline struct sk_buff *sock_alloc_send_skb(struct sock *sk,
1839	unsigned long size,
1840	int noblock, int *errcode)
1841	{
1842	return sock_alloc_send_pskb(sk, header_len: size, data_len: 0, noblock, errcode, max_page_order: 0);
1843	}
1844
1845	void *sock_kmalloc(struct sock *sk, int size, gfp_t priority);
1846	void sock_kfree_s(struct sock *sk, void *mem, int size);
1847	void sock_kzfree_s(struct sock *sk, void *mem, int size);
1848	void sk_send_sigurg(struct sock *sk);
1849
1850	static inline void sock_replace_proto(struct sock *sk, struct proto *proto)
1851	{
1852	if (sk->sk_socket)
1853	clear_bit(SOCK_SUPPORT_ZC, addr: &sk->sk_socket->flags);
1854	WRITE_ONCE(sk->sk_prot, proto);
1855	}
1856
1857	struct sockcm_cookie {
1858	u64 transmit_time;
1859	u32 mark;
1860	u32 tsflags;
1861	};
1862
1863	static inline void sockcm_init(struct sockcm_cookie *sockc,
1864	const struct sock *sk)
1865	{
1866	*sockc = (struct sockcm_cookie) {
1867	.tsflags = READ_ONCE(sk->sk_tsflags)
1868	};
1869	}
1870
1871	int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg,
1872	struct sockcm_cookie *sockc);
1873	int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
1874	struct sockcm_cookie *sockc);
1875
1876	/*
1877	* Functions to fill in entries in struct proto_ops when a protocol
1878	* does not implement a particular function.
1879	*/
1880	int sock_no_bind(struct socket *, struct sockaddr *, int);
1881	int sock_no_connect(struct socket *, struct sockaddr *, int, int);
1882	int sock_no_socketpair(struct socket *, struct socket *);
1883	int sock_no_accept(struct socket *, struct socket *, int, bool);
1884	int sock_no_getname(struct socket *, struct sockaddr *, int);
1885	int sock_no_ioctl(struct socket *, unsigned int, unsigned long);
1886	int sock_no_listen(struct socket *, int);
1887	int sock_no_shutdown(struct socket *, int);
1888	int sock_no_sendmsg(struct socket *, struct msghdr *, size_t);
1889	int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len);
1890	int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int);
1891	int sock_no_mmap(struct file *file, struct socket *sock,
1892	struct vm_area_struct *vma);
1893
1894	/*
1895	* Functions to fill in entries in struct proto_ops when a protocol
1896	* uses the inet style.
1897	*/
1898	int sock_common_getsockopt(struct socket *sock, int level, int optname,
1899	char __user *optval, int __user *optlen);
1900	int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1901	int flags);
1902	int sock_common_setsockopt(struct socket *sock, int level, int optname,
1903	sockptr_t optval, unsigned int optlen);
1904
1905	void sk_common_release(struct sock *sk);
1906
1907	/*
1908	* Default socket callbacks and setup code
1909	*/
1910
1911	/* Initialise core socket variables using an explicit uid. */
1912	void sock_init_data_uid(struct socket *sock, struct sock *sk, kuid_t uid);
1913
1914	/* Initialise core socket variables.
1915	* Assumes struct socket *sock is embedded in a struct socket_alloc.
1916	*/
1917	void sock_init_data(struct socket *sock, struct sock *sk);
1918
1919	/*
1920	* Socket reference counting postulates.
1921	*
1922	* * Each user of socket SHOULD hold a reference count.
1923	* * Each access point to socket (an hash table bucket, reference from a list,
1924	* running timer, skb in flight MUST hold a reference count.
1925	* * When reference count hits 0, it means it will never increase back.
1926	* * When reference count hits 0, it means that no references from
1927	* outside exist to this socket and current process on current CPU
1928	* is last user and may/should destroy this socket.
1929	* * sk_free is called from any context: process, BH, IRQ. When
1930	* it is called, socket has no references from outside -> sk_free
1931	* may release descendant resources allocated by the socket, but
1932	* to the time when it is called, socket is NOT referenced by any
1933	* hash tables, lists etc.
1934	* * Packets, delivered from outside (from network or from another process)
1935	* and enqueued on receive/error queues SHOULD NOT grab reference count,
1936	* when they sit in queue. Otherwise, packets will leak to hole, when
1937	* socket is looked up by one cpu and unhasing is made by another CPU.
1938	* It is true for udp/raw, netlink (leak to receive and error queues), tcp
1939	* (leak to backlog). Packet socket does all the processing inside
1940	* BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
1941	* use separate SMP lock, so that they are prone too.
1942	*/
1943
1944	/* Ungrab socket and destroy it, if it was the last reference. */
1945	static inline void sock_put(struct sock *sk)
1946	{
1947	if (refcount_dec_and_test(r: &sk->sk_refcnt))
1948	sk_free(sk);
1949	}
1950	/* Generic version of sock_put(), dealing with all sockets
1951	* (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...)
1952	*/
1953	void sock_gen_put(struct sock *sk);
1954
1955	int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested,
1956	unsigned int trim_cap, bool refcounted);
1957	static inline int sk_receive_skb(struct sock *sk, struct sk_buff *skb,
1958	const int nested)
1959	{
1960	return __sk_receive_skb(sk, skb, nested, trim_cap: 1, refcounted: true);
1961	}
1962
1963	static inline void sk_tx_queue_set(struct sock *sk, int tx_queue)
1964	{
1965	/* sk_tx_queue_mapping accept only upto a 16-bit value */
1966	if (WARN_ON_ONCE((unsigned short)tx_queue >= USHRT_MAX))
1967	return;
1968	/* Paired with READ_ONCE() in sk_tx_queue_get() and
1969	* other WRITE_ONCE() because socket lock might be not held.
1970	*/
1971	WRITE_ONCE(sk->sk_tx_queue_mapping, tx_queue);
1972	}
1973
1974	#define NO_QUEUE_MAPPING USHRT_MAX
1975
1976	static inline void sk_tx_queue_clear(struct sock *sk)
1977	{
1978	/* Paired with READ_ONCE() in sk_tx_queue_get() and
1979	* other WRITE_ONCE() because socket lock might be not held.
1980	*/
1981	WRITE_ONCE(sk->sk_tx_queue_mapping, NO_QUEUE_MAPPING);
1982	}
1983
1984	static inline int sk_tx_queue_get(const struct sock *sk)
1985	{
1986	if (sk) {
1987	/* Paired with WRITE_ONCE() in sk_tx_queue_clear()
1988	* and sk_tx_queue_set().
1989	*/
1990	int val = READ_ONCE(sk->sk_tx_queue_mapping);
1991
1992	if (val != NO_QUEUE_MAPPING)
1993	return val;
1994	}
1995	return -1;
1996	}
1997
1998	static inline void __sk_rx_queue_set(struct sock *sk,
1999	const struct sk_buff *skb,
2000	bool force_set)
2001	{
2002	#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
2003	if (skb_rx_queue_recorded(skb)) {
2004	u16 rx_queue = skb_get_rx_queue(skb);
2005
2006	if (force_set ||
2007	unlikely(READ_ONCE(sk->sk_rx_queue_mapping) != rx_queue))
2008	WRITE_ONCE(sk->sk_rx_queue_mapping, rx_queue);
2009	}
2010	#endif
2011	}
2012
2013	static inline void sk_rx_queue_set(struct sock *sk, const struct sk_buff *skb)
2014	{
2015	__sk_rx_queue_set(sk, skb, force_set: true);
2016	}
2017
2018	static inline void sk_rx_queue_update(struct sock *sk, const struct sk_buff *skb)
2019	{
2020	__sk_rx_queue_set(sk, skb, force_set: false);
2021	}
2022
2023	static inline void sk_rx_queue_clear(struct sock *sk)
2024	{
2025	#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
2026	WRITE_ONCE(sk->sk_rx_queue_mapping, NO_QUEUE_MAPPING);
2027	#endif
2028	}
2029
2030	static inline int sk_rx_queue_get(const struct sock *sk)
2031	{
2032	#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
2033	if (sk) {
2034	int res = READ_ONCE(sk->sk_rx_queue_mapping);
2035
2036	if (res != NO_QUEUE_MAPPING)
2037	return res;
2038	}
2039	#endif
2040
2041	return -1;
2042	}
2043
2044	static inline void sk_set_socket(struct sock *sk, struct socket *sock)
2045	{
2046	sk->sk_socket = sock;
2047	}
2048
2049	static inline wait_queue_head_t *sk_sleep(struct sock *sk)
2050	{
2051	BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0);
2052	return &rcu_dereference_raw(sk->sk_wq)->wait;
2053	}
2054	/* Detach socket from process context.
2055	* Announce socket dead, detach it from wait queue and inode.
2056	* Note that parent inode held reference count on this struct sock,
2057	* we do not release it in this function, because protocol
2058	* probably wants some additional cleanups or even continuing
2059	* to work with this socket (TCP).
2060	*/
2061	static inline void sock_orphan(struct sock *sk)
2062	{
2063	write_lock_bh(&sk->sk_callback_lock);
2064	sock_set_flag(sk, flag: SOCK_DEAD);
2065	sk_set_socket(sk, NULL);
2066	sk->sk_wq = NULL;
2067	write_unlock_bh(&sk->sk_callback_lock);
2068	}
2069
2070	static inline void sock_graft(struct sock *sk, struct socket *parent)
2071	{
2072	WARN_ON(parent->sk);
2073	write_lock_bh(&sk->sk_callback_lock);
2074	rcu_assign_pointer(sk->sk_wq, &parent->wq);
2075	parent->sk = sk;
2076	sk_set_socket(sk, sock: parent);
2077	sk->sk_uid = SOCK_INODE(socket: parent)->i_uid;
2078	security_sock_graft(sk, parent);
2079	write_unlock_bh(&sk->sk_callback_lock);
2080	}
2081
2082	kuid_t sock_i_uid(struct sock *sk);
2083	unsigned long __sock_i_ino(struct sock *sk);
2084	unsigned long sock_i_ino(struct sock *sk);
2085
2086	static inline kuid_t sock_net_uid(const struct net *net, const struct sock *sk)
2087	{
2088	return sk ? sk->sk_uid : make_kuid(from: net->user_ns, uid: 0);
2089	}
2090
2091	static inline u32 net_tx_rndhash(void)
2092	{
2093	u32 v = get_random_u32();
2094
2095	return v ?: 1;
2096	}
2097
2098	static inline void sk_set_txhash(struct sock *sk)
2099	{
2100	/* This pairs with READ_ONCE() in skb_set_hash_from_sk() */
2101	WRITE_ONCE(sk->sk_txhash, net_tx_rndhash());
2102	}
2103
2104	static inline bool sk_rethink_txhash(struct sock *sk)
2105	{
2106	if (sk->sk_txhash && sk->sk_txrehash == SOCK_TXREHASH_ENABLED) {
2107	sk_set_txhash(sk);
2108	return true;
2109	}
2110	return false;
2111	}
2112
2113	static inline struct dst_entry *
2114	__sk_dst_get(const struct sock *sk)
2115	{
2116	return rcu_dereference_check(sk->sk_dst_cache,
2117	lockdep_sock_is_held(sk));
2118	}
2119
2120	static inline struct dst_entry *
2121	sk_dst_get(const struct sock *sk)
2122	{
2123	struct dst_entry *dst;
2124
2125	rcu_read_lock();
2126	dst = rcu_dereference(sk->sk_dst_cache);
2127	if (dst && !rcuref_get(ref: &dst->__rcuref))
2128	dst = NULL;
2129	rcu_read_unlock();
2130	return dst;
2131	}
2132
2133	static inline void __dst_negative_advice(struct sock *sk)
2134	{
2135	struct dst_entry *ndst, *dst = __sk_dst_get(sk);
2136
2137	if (dst && dst->ops->negative_advice) {
2138	ndst = dst->ops->negative_advice(dst);
2139
2140	if (ndst != dst) {
2141	rcu_assign_pointer(sk->sk_dst_cache, ndst);
2142	sk_tx_queue_clear(sk);
2143	WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2144	}
2145	}
2146	}
2147
2148	static inline void dst_negative_advice(struct sock *sk)
2149	{
2150	sk_rethink_txhash(sk);
2151	__dst_negative_advice(sk);
2152	}
2153
2154	static inline void
2155	__sk_dst_set(struct sock *sk, struct dst_entry *dst)
2156	{
2157	struct dst_entry *old_dst;
2158
2159	sk_tx_queue_clear(sk);
2160	WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2161	old_dst = rcu_dereference_protected(sk->sk_dst_cache,
2162	lockdep_sock_is_held(sk));
2163	rcu_assign_pointer(sk->sk_dst_cache, dst);
2164	dst_release(dst: old_dst);
2165	}
2166
2167	static inline void
2168	sk_dst_set(struct sock *sk, struct dst_entry *dst)
2169	{
2170	struct dst_entry *old_dst;
2171
2172	sk_tx_queue_clear(sk);
2173	WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2174	old_dst = xchg((__force struct dst_entry **)&sk->sk_dst_cache, dst);
2175	dst_release(dst: old_dst);
2176	}
2177
2178	static inline void
2179	__sk_dst_reset(struct sock *sk)
2180	{
2181	__sk_dst_set(sk, NULL);
2182	}
2183
2184	static inline void
2185	sk_dst_reset(struct sock *sk)
2186	{
2187	sk_dst_set(sk, NULL);
2188	}
2189
2190	struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
2191
2192	struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
2193
2194	static inline void sk_dst_confirm(struct sock *sk)
2195	{
2196	if (!READ_ONCE(sk->sk_dst_pending_confirm))
2197	WRITE_ONCE(sk->sk_dst_pending_confirm, 1);
2198	}
2199
2200	static inline void sock_confirm_neigh(struct sk_buff *skb, struct neighbour *n)
2201	{
2202	if (skb_get_dst_pending_confirm(skb)) {
2203	struct sock *sk = skb->sk;
2204
2205	if (sk && READ_ONCE(sk->sk_dst_pending_confirm))
2206	WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2207	neigh_confirm(n);
2208	}
2209	}
2210
2211	bool sk_mc_loop(const struct sock *sk);
2212
2213	static inline bool sk_can_gso(const struct sock *sk)
2214	{
2215	return net_gso_ok(features: sk->sk_route_caps, gso_type: sk->sk_gso_type);
2216	}
2217
2218	void sk_setup_caps(struct sock *sk, struct dst_entry *dst);
2219
2220	static inline void sk_gso_disable(struct sock *sk)
2221	{
2222	sk->sk_gso_disabled = 1;
2223	sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2224	}
2225
2226	static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
2227	struct iov_iter *from, char *to,
2228	int copy, int offset)
2229	{
2230	if (skb->ip_summed == CHECKSUM_NONE) {
2231	__wsum csum = 0;
2232	if (!csum_and_copy_from_iter_full(addr: to, bytes: copy, csum: &csum, i: from))
2233	return -EFAULT;
2234	skb->csum = csum_block_add(csum: skb->csum, csum2: csum, offset);
2235	} else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
2236	if (!copy_from_iter_full_nocache(addr: to, bytes: copy, i: from))
2237	return -EFAULT;
2238	} else if (!copy_from_iter_full(addr: to, bytes: copy, i: from))
2239	return -EFAULT;
2240
2241	return 0;
2242	}
2243
2244	static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
2245	struct iov_iter *from, int copy)
2246	{
2247	int err, offset = skb->len;
2248
2249	err = skb_do_copy_data_nocache(sk, skb, from, to: skb_put(skb, len: copy),
2250	copy, offset);
2251	if (err)
2252	__skb_trim(skb, len: offset);
2253
2254	return err;
2255	}
2256
2257	static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from,
2258	struct sk_buff *skb,
2259	struct page *page,
2260	int off, int copy)
2261	{
2262	int err;
2263
2264	err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off,
2265	copy, offset: skb->len);
2266	if (err)
2267	return err;
2268
2269	skb_len_add(skb, delta: copy);
2270	sk_wmem_queued_add(sk, val: copy);
2271	sk_mem_charge(sk, size: copy);
2272	return 0;
2273	}
2274
2275	/**
2276	* sk_wmem_alloc_get - returns write allocations
2277	* @sk: socket
2278	*
2279	* Return: sk_wmem_alloc minus initial offset of one
2280	*/
2281	static inline int sk_wmem_alloc_get(const struct sock *sk)
2282	{
2283	return refcount_read(r: &sk->sk_wmem_alloc) - 1;
2284	}
2285
2286	/**
2287	* sk_rmem_alloc_get - returns read allocations
2288	* @sk: socket
2289	*
2290	* Return: sk_rmem_alloc
2291	*/
2292	static inline int sk_rmem_alloc_get(const struct sock *sk)
2293	{
2294	return atomic_read(v: &sk->sk_rmem_alloc);
2295	}
2296
2297	/**
2298	* sk_has_allocations - check if allocations are outstanding
2299	* @sk: socket
2300	*
2301	* Return: true if socket has write or read allocations
2302	*/
2303	static inline bool sk_has_allocations(const struct sock *sk)
2304	{
2305	return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk);
2306	}
2307
2308	/**
2309	* skwq_has_sleeper - check if there are any waiting processes
2310	* @wq: struct socket_wq
2311	*
2312	* Return: true if socket_wq has waiting processes
2313	*
2314	* The purpose of the skwq_has_sleeper and sock_poll_wait is to wrap the memory
2315	* barrier call. They were added due to the race found within the tcp code.
2316	*
2317	* Consider following tcp code paths::
2318	*
2319	* CPU1 CPU2
2320	* sys_select receive packet
2321	* ... ...
2322	* __add_wait_queue update tp->rcv_nxt
2323	* ... ...
2324	* tp->rcv_nxt check sock_def_readable
2325	* ... {
2326	* schedule rcu_read_lock();
2327	* wq = rcu_dereference(sk->sk_wq);
2328	* if (wq && waitqueue_active(&wq->wait))
2329	* wake_up_interruptible(&wq->wait)
2330	* ...
2331	* }
2332	*
2333	* The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
2334	* in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1
2335	* could then endup calling schedule and sleep forever if there are no more
2336	* data on the socket.
2337	*
2338	*/
2339	static inline bool skwq_has_sleeper(struct socket_wq *wq)
2340	{
2341	return wq && wq_has_sleeper(wq_head: &wq->wait);
2342	}
2343
2344	/**
2345	* sock_poll_wait - place memory barrier behind the poll_wait call.
2346	* @filp: file
2347	* @sock: socket to wait on
2348	* @p: poll_table
2349	*
2350	* See the comments in the wq_has_sleeper function.
2351	*/
2352	static inline void sock_poll_wait(struct file *filp, struct socket *sock,
2353	poll_table *p)
2354	{
2355	if (!poll_does_not_wait(p)) {
2356	poll_wait(filp, wait_address: &sock->wq.wait, p);
2357	/* We need to be sure we are in sync with the
2358	* socket flags modification.
2359	*
2360	* This memory barrier is paired in the wq_has_sleeper.
2361	*/
2362	smp_mb();
2363	}
2364	}
2365
2366	static inline void skb_set_hash_from_sk(struct sk_buff *skb, struct sock *sk)
2367	{
2368	/* This pairs with WRITE_ONCE() in sk_set_txhash() */
2369	u32 txhash = READ_ONCE(sk->sk_txhash);
2370
2371	if (txhash) {
2372	skb->l4_hash = 1;
2373	skb->hash = txhash;
2374	}
2375	}
2376
2377	void skb_set_owner_w(struct sk_buff *skb, struct sock *sk);
2378
2379	/*
2380	* Queue a received datagram if it will fit. Stream and sequenced
2381	* protocols can't normally use this as they need to fit buffers in
2382	* and play with them.
2383	*
2384	* Inlined as it's very short and called for pretty much every
2385	* packet ever received.
2386	*/
2387	static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
2388	{
2389	skb_orphan(skb);
2390	skb->sk = sk;
2391	skb->destructor = sock_rfree;
2392	atomic_add(i: skb->truesize, v: &sk->sk_rmem_alloc);
2393	sk_mem_charge(sk, size: skb->truesize);
2394	}
2395
2396	static inline __must_check bool skb_set_owner_sk_safe(struct sk_buff *skb, struct sock *sk)
2397	{
2398	if (sk && refcount_inc_not_zero(r: &sk->sk_refcnt)) {
2399	skb_orphan(skb);
2400	skb->destructor = sock_efree;
2401	skb->sk = sk;
2402	return true;
2403	}
2404	return false;
2405	}
2406
2407	static inline struct sk_buff *skb_clone_and_charge_r(struct sk_buff *skb, struct sock *sk)
2408	{
2409	skb = skb_clone(skb, priority: sk_gfp_mask(sk, GFP_ATOMIC));
2410	if (skb) {
2411	if (sk_rmem_schedule(sk, skb, size: skb->truesize)) {
2412	skb_set_owner_r(skb, sk);
2413	return skb;
2414	}
2415	__kfree_skb(skb);
2416	}
2417	return NULL;
2418	}
2419
2420	static inline void skb_prepare_for_gro(struct sk_buff *skb)
2421	{
2422	if (skb->destructor != sock_wfree) {
2423	skb_orphan(skb);
2424	return;
2425	}
2426	skb->slow_gro = 1;
2427	}
2428
2429	void sk_reset_timer(struct sock *sk, struct timer_list *timer,
2430	unsigned long expires);
2431
2432	void sk_stop_timer(struct sock *sk, struct timer_list *timer);
2433
2434	void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer);
2435
2436	int __sk_queue_drop_skb(struct sock *sk, struct sk_buff_head *sk_queue,
2437	struct sk_buff *skb, unsigned int flags,
2438	void (*destructor)(struct sock *sk,
2439	struct sk_buff *skb));
2440	int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
2441
2442	int sock_queue_rcv_skb_reason(struct sock *sk, struct sk_buff *skb,
2443	enum skb_drop_reason *reason);
2444
2445	static inline int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
2446	{
2447	return sock_queue_rcv_skb_reason(sk, skb, NULL);
2448	}
2449
2450	int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
2451	struct sk_buff *sock_dequeue_err_skb(struct sock *sk);
2452
2453	/*
2454	* Recover an error report and clear atomically
2455	*/
2456
2457	static inline int sock_error(struct sock *sk)
2458	{
2459	int err;
2460
2461	/* Avoid an atomic operation for the common case.
2462	* This is racy since another cpu/thread can change sk_err under us.
2463	*/
2464	if (likely(data_race(!sk->sk_err)))
2465	return 0;
2466
2467	err = xchg(&sk->sk_err, 0);
2468	return -err;
2469	}
2470
2471	void sk_error_report(struct sock *sk);
2472
2473	static inline unsigned long sock_wspace(struct sock *sk)
2474	{
2475	int amt = 0;
2476
2477	if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
2478	amt = sk->sk_sndbuf - refcount_read(r: &sk->sk_wmem_alloc);
2479	if (amt < 0)
2480	amt = 0;
2481	}
2482	return amt;
2483	}
2484
2485	/* Note:
2486	* We use sk->sk_wq_raw, from contexts knowing this
2487	* pointer is not NULL and cannot disappear/change.
2488	*/
2489	static inline void sk_set_bit(int nr, struct sock *sk)
2490	{
2491	if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2492	!sock_flag(sk, flag: SOCK_FASYNC))
2493	return;
2494
2495	set_bit(nr, addr: &sk->sk_wq_raw->flags);
2496	}
2497
2498	static inline void sk_clear_bit(int nr, struct sock *sk)
2499	{
2500	if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2501	!sock_flag(sk, flag: SOCK_FASYNC))
2502	return;
2503
2504	clear_bit(nr, addr: &sk->sk_wq_raw->flags);
2505	}
2506
2507	static inline void sk_wake_async(const struct sock *sk, int how, int band)
2508	{
2509	if (sock_flag(sk, flag: SOCK_FASYNC)) {
2510	rcu_read_lock();
2511	sock_wake_async(rcu_dereference(sk->sk_wq), how, band);
2512	rcu_read_unlock();
2513	}
2514	}
2515
2516	/* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might
2517	* need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak.
2518	* Note: for send buffers, TCP works better if we can build two skbs at
2519	* minimum.
2520	*/
2521	#define TCP_SKB_MIN_TRUESIZE (2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff)))
2522
2523	#define SOCK_MIN_SNDBUF (TCP_SKB_MIN_TRUESIZE * 2)
2524	#define SOCK_MIN_RCVBUF TCP_SKB_MIN_TRUESIZE
2525
2526	static inline void sk_stream_moderate_sndbuf(struct sock *sk)
2527	{
2528	u32 val;
2529
2530	if (sk->sk_userlocks & SOCK_SNDBUF_LOCK)
2531	return;
2532
2533	val = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
2534	val = max_t(u32, val, sk_unused_reserved_mem(sk));
2535
2536	WRITE_ONCE(sk->sk_sndbuf, max_t(u32, val, SOCK_MIN_SNDBUF));
2537	}
2538
2539	/**
2540	* sk_page_frag - return an appropriate page_frag
2541	* @sk: socket
2542	*
2543	* Use the per task page_frag instead of the per socket one for
2544	* optimization when we know that we're in process context and own
2545	* everything that's associated with %current.
2546	*
2547	* Both direct reclaim and page faults can nest inside other
2548	* socket operations and end up recursing into sk_page_frag()
2549	* while it's already in use: explicitly avoid task page_frag
2550	* when users disable sk_use_task_frag.
2551	*
2552	* Return: a per task page_frag if context allows that,
2553	* otherwise a per socket one.
2554	*/
2555	static inline struct page_frag *sk_page_frag(struct sock *sk)
2556	{
2557	if (sk->sk_use_task_frag)
2558	return &current->task_frag;
2559
2560	return &sk->sk_frag;
2561	}
2562
2563	bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag);
2564
2565	/*
2566	* Default write policy as shown to user space via poll/select/SIGIO
2567	*/
2568	static inline bool sock_writeable(const struct sock *sk)
2569	{
2570	return refcount_read(r: &sk->sk_wmem_alloc) < (READ_ONCE(sk->sk_sndbuf) >> 1);
2571	}
2572
2573	static inline gfp_t gfp_any(void)
2574	{
2575	return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2576	}
2577
2578	static inline gfp_t gfp_memcg_charge(void)
2579	{
2580	return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2581	}
2582
2583	static inline long sock_rcvtimeo(const struct sock *sk, bool noblock)
2584	{
2585	return noblock ? 0 : sk->sk_rcvtimeo;
2586	}
2587
2588	static inline long sock_sndtimeo(const struct sock *sk, bool noblock)
2589	{
2590	return noblock ? 0 : sk->sk_sndtimeo;
2591	}
2592
2593	static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
2594	{
2595	int v = waitall ? len : min_t(int, READ_ONCE(sk->sk_rcvlowat), len);
2596
2597	return v ?: 1;
2598	}
2599
2600	/* Alas, with timeout socket operations are not restartable.
2601	* Compare this to poll().
2602	*/
2603	static inline int sock_intr_errno(long timeo)
2604	{
2605	return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
2606	}
2607
2608	struct sock_skb_cb {
2609	u32 dropcount;
2610	};
2611
2612	/* Store sock_skb_cb at the end of skb->cb[] so protocol families
2613	* using skb->cb[] would keep using it directly and utilize its
2614	* alignement guarantee.
2615	*/
2616	#define SOCK_SKB_CB_OFFSET ((sizeof_field(struct sk_buff, cb) - \
2617	sizeof(struct sock_skb_cb)))
2618
2619	#define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \
2620	SOCK_SKB_CB_OFFSET))
2621
2622	#define sock_skb_cb_check_size(size) \
2623	BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET)
2624
2625	static inline void
2626	sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb)
2627	{
2628	SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, flag: SOCK_RXQ_OVFL) ?
2629	atomic_read(v: &sk->sk_drops) : 0;
2630	}
2631
2632	static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb)
2633	{
2634	int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs);
2635
2636	atomic_add(i: segs, v: &sk->sk_drops);
2637	}
2638
2639	static inline ktime_t sock_read_timestamp(struct sock *sk)
2640	{
2641	#if BITS_PER_LONG==32
2642	unsigned int seq;
2643	ktime_t kt;
2644
2645	do {
2646	seq = read_seqbegin(&sk->sk_stamp_seq);
2647	kt = sk->sk_stamp;
2648	} while (read_seqretry(&sk->sk_stamp_seq, seq));
2649
2650	return kt;
2651	#else
2652	return READ_ONCE(sk->sk_stamp);
2653	#endif
2654	}
2655
2656	static inline void sock_write_timestamp(struct sock *sk, ktime_t kt)
2657	{
2658	#if BITS_PER_LONG==32
2659	write_seqlock(&sk->sk_stamp_seq);
2660	sk->sk_stamp = kt;
2661	write_sequnlock(&sk->sk_stamp_seq);
2662	#else
2663	WRITE_ONCE(sk->sk_stamp, kt);
2664	#endif
2665	}
2666
2667	void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
2668	struct sk_buff *skb);
2669	void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
2670	struct sk_buff *skb);
2671
2672	static inline void
2673	sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
2674	{
2675	struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
2676	u32 tsflags = READ_ONCE(sk->sk_tsflags);
2677	ktime_t kt = skb->tstamp;
2678	/*
2679	* generate control messages if
2680	* - receive time stamping in software requested
2681	* - software time stamp available and wanted
2682	* - hardware time stamps available and wanted
2683	*/
2684	if (sock_flag(sk, flag: SOCK_RCVTSTAMP) ||
2685	(tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) ||
2686	(kt && tsflags & SOF_TIMESTAMPING_SOFTWARE) ||
2687	(hwtstamps->hwtstamp &&
2688	(tsflags & SOF_TIMESTAMPING_RAW_HARDWARE)))
2689	__sock_recv_timestamp(msg, sk, skb);
2690	else
2691	sock_write_timestamp(sk, kt);
2692
2693	if (sock_flag(sk, flag: SOCK_WIFI_STATUS) && skb_wifi_acked_valid(skb))
2694	__sock_recv_wifi_status(msg, sk, skb);
2695	}
2696
2697	void __sock_recv_cmsgs(struct msghdr *msg, struct sock *sk,
2698	struct sk_buff *skb);
2699
2700	#define SK_DEFAULT_STAMP (-1L * NSEC_PER_SEC)
2701	static inline void sock_recv_cmsgs(struct msghdr *msg, struct sock *sk,
2702	struct sk_buff *skb)
2703	{
2704	#define FLAGS_RECV_CMSGS ((1UL << SOCK_RXQ_OVFL) | \
2705	(1UL << SOCK_RCVTSTAMP) | \
2706	(1UL << SOCK_RCVMARK))
2707	#define TSFLAGS_ANY (SOF_TIMESTAMPING_SOFTWARE | \
2708	SOF_TIMESTAMPING_RAW_HARDWARE)
2709
2710	if (sk->sk_flags & FLAGS_RECV_CMSGS ||
2711	READ_ONCE(sk->sk_tsflags) & TSFLAGS_ANY)
2712	__sock_recv_cmsgs(msg, sk, skb);
2713	else if (unlikely(sock_flag(sk, SOCK_TIMESTAMP)))
2714	sock_write_timestamp(sk, kt: skb->tstamp);
2715	else if (unlikely(sock_read_timestamp(sk) == SK_DEFAULT_STAMP))
2716	sock_write_timestamp(sk, kt: 0);
2717	}
2718
2719	void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags);
2720
2721	/**
2722	* _sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
2723	* @sk: socket sending this packet
2724	* @tsflags: timestamping flags to use
2725	* @tx_flags: completed with instructions for time stamping
2726	* @tskey: filled in with next sk_tskey (not for TCP, which uses seqno)
2727	*
2728	* Note: callers should take care of initial ``*tx_flags`` value (usually 0)
2729	*/
2730	static inline void _sock_tx_timestamp(struct sock *sk, __u16 tsflags,
2731	__u8 *tx_flags, __u32 *tskey)
2732	{
2733	if (unlikely(tsflags)) {
2734	__sock_tx_timestamp(tsflags, tx_flags);
2735	if (tsflags & SOF_TIMESTAMPING_OPT_ID && tskey &&
2736	tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK)
2737	*tskey = atomic_inc_return(v: &sk->sk_tskey) - 1;
2738	}
2739	if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS)))
2740	*tx_flags |= SKBTX_WIFI_STATUS;
2741	}
2742
2743	static inline void sock_tx_timestamp(struct sock *sk, __u16 tsflags,
2744	__u8 *tx_flags)
2745	{
2746	_sock_tx_timestamp(sk, tsflags, tx_flags, NULL);
2747	}
2748
2749	static inline void skb_setup_tx_timestamp(struct sk_buff *skb, __u16 tsflags)
2750	{
2751	_sock_tx_timestamp(sk: skb->sk, tsflags, tx_flags: &skb_shinfo(skb)->tx_flags,
2752	tskey: &skb_shinfo(skb)->tskey);
2753	}
2754
2755	static inline bool sk_is_inet(const struct sock *sk)
2756	{
2757	int family = READ_ONCE(sk->sk_family);
2758
2759	return family == AF_INET || family == AF_INET6;
2760	}
2761
2762	static inline bool sk_is_tcp(const struct sock *sk)
2763	{
2764	return sk_is_inet(sk) &&
2765	sk->sk_type == SOCK_STREAM &&
2766	sk->sk_protocol == IPPROTO_TCP;
2767	}
2768
2769	static inline bool sk_is_udp(const struct sock *sk)
2770	{
2771	return sk_is_inet(sk) &&
2772	sk->sk_type == SOCK_DGRAM &&
2773	sk->sk_protocol == IPPROTO_UDP;
2774	}
2775
2776	static inline bool sk_is_stream_unix(const struct sock *sk)
2777	{
2778	return sk->sk_family == AF_UNIX && sk->sk_type == SOCK_STREAM;
2779	}
2780
2781	/**
2782	* sk_eat_skb - Release a skb if it is no longer needed
2783	* @sk: socket to eat this skb from
2784	* @skb: socket buffer to eat
2785	*
2786	* This routine must be called with interrupts disabled or with the socket
2787	* locked so that the sk_buff queue operation is ok.
2788	*/
2789	static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb)
2790	{
2791	__skb_unlink(skb, list: &sk->sk_receive_queue);
2792	__kfree_skb(skb);
2793	}
2794
2795	static inline bool
2796	skb_sk_is_prefetched(struct sk_buff *skb)
2797	{
2798	#ifdef CONFIG_INET
2799	return skb->destructor == sock_pfree;
2800	#else
2801	return false;
2802	#endif /* CONFIG_INET */
2803	}
2804
2805	/* This helper checks if a socket is a full socket,
2806	* ie _not_ a timewait or request socket.
2807	*/
2808	static inline bool sk_fullsock(const struct sock *sk)
2809	{
2810	return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV);
2811	}
2812
2813	static inline bool
2814	sk_is_refcounted(struct sock *sk)
2815	{
2816	/* Only full sockets have sk->sk_flags. */
2817	return !sk_fullsock(sk) || !sock_flag(sk, flag: SOCK_RCU_FREE);
2818	}
2819
2820	/* Checks if this SKB belongs to an HW offloaded socket
2821	* and whether any SW fallbacks are required based on dev.
2822	* Check decrypted mark in case skb_orphan() cleared socket.
2823	*/
2824	static inline struct sk_buff *sk_validate_xmit_skb(struct sk_buff *skb,
2825	struct net_device *dev)
2826	{
2827	#ifdef CONFIG_SOCK_VALIDATE_XMIT
2828	struct sock *sk = skb->sk;
2829
2830	if (sk && sk_fullsock(sk) && sk->sk_validate_xmit_skb) {
2831	skb = sk->sk_validate_xmit_skb(sk, dev, skb);
2832	#ifdef CONFIG_TLS_DEVICE
2833	} else if (unlikely(skb->decrypted)) {
2834	pr_warn_ratelimited("unencrypted skb with no associated socket - dropping\n");
2835	kfree_skb(skb);
2836	skb = NULL;
2837	#endif
2838	}
2839	#endif
2840
2841	return skb;
2842	}
2843
2844	/* This helper checks if a socket is a LISTEN or NEW_SYN_RECV
2845	* SYNACK messages can be attached to either ones (depending on SYNCOOKIE)
2846	*/
2847	static inline bool sk_listener(const struct sock *sk)
2848	{
2849	return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV);
2850	}
2851
2852	void sock_enable_timestamp(struct sock *sk, enum sock_flags flag);
2853	int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level,
2854	int type);
2855
2856	bool sk_ns_capable(const struct sock *sk,
2857	struct user_namespace *user_ns, int cap);
2858	bool sk_capable(const struct sock *sk, int cap);
2859	bool sk_net_capable(const struct sock *sk, int cap);
2860
2861	void sk_get_meminfo(const struct sock *sk, u32 *meminfo);
2862
2863	/* Take into consideration the size of the struct sk_buff overhead in the
2864	* determination of these values, since that is non-constant across
2865	* platforms. This makes socket queueing behavior and performance
2866	* not depend upon such differences.
2867	*/
2868	#define _SK_MEM_PACKETS 256
2869	#define _SK_MEM_OVERHEAD SKB_TRUESIZE(256)
2870	#define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2871	#define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2872
2873	extern __u32 sysctl_wmem_max;
2874	extern __u32 sysctl_rmem_max;
2875
2876	extern int sysctl_tstamp_allow_data;
2877
2878	extern __u32 sysctl_wmem_default;
2879	extern __u32 sysctl_rmem_default;
2880
2881	#define SKB_FRAG_PAGE_ORDER get_order(32768)
2882	DECLARE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
2883
2884	static inline int sk_get_wmem0(const struct sock *sk, const struct proto *proto)
2885	{
2886	/* Does this proto have per netns sysctl_wmem ? */
2887	if (proto->sysctl_wmem_offset)
2888	return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_wmem_offset));
2889
2890	return READ_ONCE(*proto->sysctl_wmem);
2891	}
2892
2893	static inline int sk_get_rmem0(const struct sock *sk, const struct proto *proto)
2894	{
2895	/* Does this proto have per netns sysctl_rmem ? */
2896	if (proto->sysctl_rmem_offset)
2897	return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_rmem_offset));
2898
2899	return READ_ONCE(*proto->sysctl_rmem);
2900	}
2901
2902	/* Default TCP Small queue budget is ~1 ms of data (1sec >> 10)
2903	* Some wifi drivers need to tweak it to get more chunks.
2904	* They can use this helper from their ndo_start_xmit()
2905	*/
2906	static inline void sk_pacing_shift_update(struct sock *sk, int val)
2907	{
2908	if (!sk || !sk_fullsock(sk) || READ_ONCE(sk->sk_pacing_shift) == val)
2909	return;
2910	WRITE_ONCE(sk->sk_pacing_shift, val);
2911	}
2912
2913	/* if a socket is bound to a device, check that the given device
2914	* index is either the same or that the socket is bound to an L3
2915	* master device and the given device index is also enslaved to
2916	* that L3 master
2917	*/
2918	static inline bool sk_dev_equal_l3scope(struct sock *sk, int dif)
2919	{
2920	int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
2921	int mdif;
2922
2923	if (!bound_dev_if || bound_dev_if == dif)
2924	return true;
2925
2926	mdif = l3mdev_master_ifindex_by_index(net: sock_net(sk), ifindex: dif);
2927	if (mdif && mdif == bound_dev_if)
2928	return true;
2929
2930	return false;
2931	}
2932
2933	void sock_def_readable(struct sock *sk);
2934
2935	int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk);
2936	void sock_set_timestamp(struct sock *sk, int optname, bool valbool);
2937	int sock_set_timestamping(struct sock *sk, int optname,
2938	struct so_timestamping timestamping);
2939
2940	void sock_enable_timestamps(struct sock *sk);
2941	void sock_no_linger(struct sock *sk);
2942	void sock_set_keepalive(struct sock *sk);
2943	void sock_set_priority(struct sock *sk, u32 priority);
2944	void sock_set_rcvbuf(struct sock *sk, int val);
2945	void sock_set_mark(struct sock *sk, u32 val);
2946	void sock_set_reuseaddr(struct sock *sk);
2947	void sock_set_reuseport(struct sock *sk);
2948	void sock_set_sndtimeo(struct sock *sk, s64 secs);
2949
2950	int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len);
2951
2952	int sock_get_timeout(long timeo, void *optval, bool old_timeval);
2953	int sock_copy_user_timeval(struct __kernel_sock_timeval *tv,
2954	sockptr_t optval, int optlen, bool old_timeval);
2955
2956	int sock_ioctl_inout(struct sock *sk, unsigned int cmd,
2957	void __user *arg, void *karg, size_t size);
2958	int sk_ioctl(struct sock *sk, unsigned int cmd, void __user *arg);
2959	static inline bool sk_is_readable(struct sock *sk)
2960	{
2961	if (sk->sk_prot->sock_is_readable)
2962	return sk->sk_prot->sock_is_readable(sk);
2963	return false;
2964	}
2965	#endif /* _SOCK_H */
2966