xref: /linux/include/net/sock.h (revision 734bef548a96e8774d6eef5dfa2026c6edc4e80b)
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 	union {
85 		struct slock_owned {
86 			int		owned;
87 			spinlock_t	slock;
88 		};
89 		long	combined;
90 	};
91 	wait_queue_head_t	wq;
92 	/*
93 	 * We express the mutex-alike socket_lock semantics
94 	 * to the lock validator by explicitly managing
95 	 * the slock as a lock variant (in addition to
96 	 * the slock itself):
97 	 */
98 #ifdef CONFIG_DEBUG_LOCK_ALLOC
99 	struct lockdep_map dep_map;
100 #endif
101 } socket_lock_t;
102 
103 struct sock;
104 struct proto;
105 struct net;
106 
107 typedef __u32 __bitwise __portpair;
108 typedef __u64 __bitwise __addrpair;
109 
110 /**
111  *	struct sock_common - minimal network layer representation of sockets
112  *	@skc_daddr: Foreign IPv4 addr
113  *	@skc_rcv_saddr: Bound local IPv4 addr
114  *	@skc_addrpair: 8-byte-aligned __u64 union of @skc_daddr & @skc_rcv_saddr
115  *	@skc_hash: hash value used with various protocol lookup tables
116  *	@skc_u16hashes: two u16 hash values used by UDP lookup tables
117  *	@skc_dport: placeholder for inet_dport/tw_dport
118  *	@skc_num: placeholder for inet_num/tw_num
119  *	@skc_portpair: __u32 union of @skc_dport & @skc_num
120  *	@skc_family: network address family
121  *	@skc_state: Connection state
122  *	@skc_reuse: %SO_REUSEADDR setting
123  *	@skc_reuseport: %SO_REUSEPORT setting
124  *	@skc_ipv6only: socket is IPV6 only
125  *	@skc_net_refcnt: socket is using net ref counting
126  *	@skc_bypass_prot_mem: bypass the per-protocol memory accounting for skb
127  *	@skc_bound_dev_if: bound device index if != 0
128  *	@skc_bind_node: bind hash linkage for various protocol lookup tables
129  *	@skc_portaddr_node: second hash linkage for UDP
130  *	@skc_prot: protocol handlers inside a network family
131  *	@skc_net: reference to the network namespace of this socket
132  *	@skc_v6_daddr: IPV6 destination address
133  *	@skc_v6_rcv_saddr: IPV6 source address
134  *	@skc_cookie: socket's cookie value
135  *	@skc_node: main hash linkage for various protocol lookup tables
136  *	@skc_nulls_node: main hash linkage for TCP
137  *	@skc_tx_queue_mapping: tx queue number for this connection
138  *	@skc_rx_queue_mapping: rx queue number for this connection
139  *	@skc_flags: place holder for sk_flags
140  *		%SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE,
141  *		%SO_OOBINLINE settings, %SO_TIMESTAMPING settings
142  *	@skc_listener: connection request listener socket (aka rsk_listener)
143  *		[union with @skc_flags]
144  *	@skc_tw_dr: (aka tw_dr) ptr to &struct inet_timewait_death_row
145  *		[union with @skc_flags]
146  *	@skc_incoming_cpu: record/match cpu processing incoming packets
147  *	@skc_rcv_wnd: (aka rsk_rcv_wnd) TCP receive window size (possibly scaled)
148  *		[union with @skc_incoming_cpu]
149  *	@skc_tw_rcv_nxt: (aka tw_rcv_nxt) TCP window next expected seq number
150  *		[union with @skc_incoming_cpu]
151  *	@skc_refcnt: reference count
152  *
153  *	This is the minimal network layer representation of sockets, the header
154  *	for struct sock and struct inet_timewait_sock.
155  */
156 struct sock_common {
157 	union {
158 		__addrpair	skc_addrpair;
159 		struct {
160 			__be32	skc_daddr;
161 			__be32	skc_rcv_saddr;
162 		};
163 	};
164 	union  {
165 		unsigned int	skc_hash;
166 		__u16		skc_u16hashes[2];
167 	};
168 	/* skc_dport && skc_num must be grouped as well */
169 	union {
170 		__portpair	skc_portpair;
171 		struct {
172 			__be16	skc_dport;
173 			__u16	skc_num;
174 		};
175 	};
176 
177 	unsigned short		skc_family;
178 	volatile unsigned char	skc_state;
179 	unsigned char		skc_reuse:4;
180 	unsigned char		skc_reuseport:1;
181 	unsigned char		skc_ipv6only:1;
182 	unsigned char		skc_net_refcnt:1;
183 	unsigned char		skc_bypass_prot_mem:1;
184 	int			skc_bound_dev_if;
185 	union {
186 		struct hlist_node	skc_bind_node;
187 		struct hlist_node	skc_portaddr_node;
188 	};
189 	struct proto		*skc_prot;
190 	possible_net_t		skc_net;
191 
192 #if IS_ENABLED(CONFIG_IPV6)
193 	struct in6_addr		skc_v6_daddr;
194 	struct in6_addr		skc_v6_rcv_saddr;
195 #endif
196 
197 	atomic64_t		skc_cookie;
198 
199 	/* following fields are padding to force
200 	 * offset(struct sock, sk_refcnt) == 128 on 64bit arches
201 	 * assuming IPV6 is enabled. We use this padding differently
202 	 * for different kind of 'sockets'
203 	 */
204 	union {
205 		unsigned long	skc_flags;
206 		struct sock	*skc_listener; /* request_sock */
207 		struct inet_timewait_death_row *skc_tw_dr; /* inet_timewait_sock */
208 	};
209 	/*
210 	 * fields between dontcopy_begin/dontcopy_end
211 	 * are not copied in sock_copy()
212 	 */
213 	/* private: */
214 	int			skc_dontcopy_begin[0];
215 	/* public: */
216 	union {
217 		struct hlist_node	skc_node;
218 		struct hlist_nulls_node skc_nulls_node;
219 	};
220 	unsigned short		skc_tx_queue_mapping;
221 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
222 	unsigned short		skc_rx_queue_mapping;
223 #endif
224 	union {
225 		int		skc_incoming_cpu;
226 		u32		skc_rcv_wnd;
227 		u32		skc_tw_rcv_nxt; /* struct tcp_timewait_sock  */
228 	};
229 
230 	refcount_t		skc_refcnt;
231 	/* private: */
232 	int                     skc_dontcopy_end[0];
233 	union {
234 		u32		skc_rxhash;
235 		u32		skc_window_clamp;
236 		u32		skc_tw_snd_nxt; /* struct tcp_timewait_sock */
237 	};
238 	/* public: */
239 };
240 
241 struct bpf_local_storage;
242 struct sk_filter;
243 
244 /**
245   *	struct sock - network layer representation of sockets
246   *	@__sk_common: shared layout with inet_timewait_sock
247   *	@sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
248   *	@sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
249   *	@sk_lock:	synchronizer
250   *	@sk_kern_sock: True if sock is using kernel lock classes
251   *	@sk_rcvbuf: size of receive buffer in bytes
252   *	@sk_wq: sock wait queue and async head
253   *	@sk_rx_dst: receive input route used by early demux
254   *	@sk_rx_dst_ifindex: ifindex for @sk_rx_dst
255   *	@sk_rx_dst_cookie: cookie for @sk_rx_dst
256   *	@sk_dst_cache: destination cache
257   *	@sk_dst_pending_confirm: need to confirm neighbour
258   *	@sk_policy: flow policy
259   *	@psp_assoc: PSP association, if socket is PSP-secured
260   *	@sk_receive_queue: incoming packets
261   *	@sk_wmem_alloc: transmit queue bytes committed
262   *	@sk_tsq_flags: TCP Small Queues flags
263   *	@sk_write_queue: Packet sending queue
264   *	@sk_omem_alloc: "o" is "option" or "other"
265   *	@sk_wmem_queued: persistent queue size
266   *	@sk_forward_alloc: space allocated forward
267   *	@sk_reserved_mem: space reserved and non-reclaimable for the socket
268   *	@sk_napi_id: id of the last napi context to receive data for sk
269   *	@sk_ll_usec: usecs to busypoll when there is no data
270   *	@sk_allocation: allocation mode
271   *	@sk_pacing_rate: Pacing rate (if supported by transport/packet scheduler)
272   *	@sk_pacing_status: Pacing status (requested, handled by sch_fq)
273   *	@sk_max_pacing_rate: Maximum pacing rate (%SO_MAX_PACING_RATE)
274   *	@sk_sndbuf: size of send buffer in bytes
275   *	@sk_no_check_tx: %SO_NO_CHECK setting, set checksum in TX packets
276   *	@sk_no_check_rx: allow zero checksum in RX packets
277   *	@sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
278   *	@sk_gso_disabled: if set, NETIF_F_GSO_MASK is forbidden.
279   *	@sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
280   *	@sk_gso_max_size: Maximum GSO segment size to build
281   *	@sk_gso_max_segs: Maximum number of GSO segments
282   *	@sk_pacing_shift: scaling factor for TCP Small Queues
283   *	@sk_lingertime: %SO_LINGER l_linger setting
284   *	@sk_backlog: always used with the per-socket spinlock held
285   *	@sk_callback_lock: used with the callbacks in the end of this struct
286   *	@sk_error_queue: rarely used
287   *	@sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt,
288   *			  IPV6_ADDRFORM for instance)
289   *	@sk_err: last error
290   *	@sk_err_soft: errors that don't cause failure but are the cause of a
291   *		      persistent failure not just 'timed out'
292   *	@sk_drops: raw/udp drops counter
293   *	@sk_drop_counters: optional pointer to numa_drop_counters
294   *	@sk_ack_backlog: current listen backlog
295   *	@sk_max_ack_backlog: listen backlog set in listen()
296   *	@sk_uid: user id of owner
297   *	@sk_ino: inode number (zero if orphaned)
298   *	@sk_prefer_busy_poll: prefer busypolling over softirq processing
299   *	@sk_busy_poll_budget: napi processing budget when busypolling
300   *	@sk_priority: %SO_PRIORITY setting
301   *	@sk_type: socket type (%SOCK_STREAM, etc)
302   *	@sk_protocol: which protocol this socket belongs in this network family
303   *	@sk_peer_lock: lock protecting @sk_peer_pid and @sk_peer_cred
304   *	@sk_peer_pid: &struct pid for this socket's peer, by pid type
305   *	@sk_peer_cred: %SO_PEERCRED setting
306   *	@sk_rcvlowat: %SO_RCVLOWAT setting
307   *	@sk_rcvtimeo: %SO_RCVTIMEO setting
308   *	@sk_sndtimeo: %SO_SNDTIMEO setting
309   *	@sk_txhash: computed flow hash for use on transmit
310   *	@sk_txrehash: enable TX hash rethink
311   *	@sk_filter: socket filtering instructions
312   *	@sk_timer: sock cleanup timer
313   *	@tcp_retransmit_timer: tcp retransmit timer
314   *	@mptcp_retransmit_timer: mptcp retransmit timer
315   *	@sk_stamp: time stamp of last packet received
316   *	@sk_stamp_seq: lock for accessing sk_stamp on 32 bit architectures only
317   *	@sk_tsflags: SO_TIMESTAMPING flags
318   *	@sk_bpf_cb_flags: used in bpf_setsockopt()
319   *	@sk_use_task_frag: allow sk_page_frag() to use current->task_frag.
320   *			   Sockets that can be used under memory reclaim should
321   *			   set this to false.
322   *	@sk_bind_phc: SO_TIMESTAMPING bind PHC index of PTP virtual clock
323   *	              for timestamping
324   *	@sk_tskey: counter to disambiguate concurrent tstamp requests
325   *	@sk_tx_queue_mapping_jiffies: time in jiffies of last @sk_tx_queue_mapping refresh.
326   *	@sk_zckey: counter to order MSG_ZEROCOPY notifications
327   *	@sk_socket: Identd and reporting IO signals
328   *	@sk_user_data: RPC layer private data. Write-protected by @sk_callback_lock.
329   *	@sk_frag: cached page frag
330   *	@sk_peek_off: current peek_offset value
331   *	@sk_send_head: front of stuff to transmit
332   *	@tcp_rtx_queue: TCP re-transmit queue [union with @sk_send_head]
333   *	@sk_security: used by security modules
334   *	@sk_mark: generic packet mark
335   *	@sk_cgrp_data: cgroup data for this cgroup
336   *	@sk_memcg: this socket's memory cgroup association
337   *	@sk_write_pending: a write to stream socket waits to start
338   *	@sk_disconnects: number of disconnect operations performed on this sock
339   *	@sk_state_change: callback to indicate change in the state of the sock
340   *	@sk_data_ready: callback to indicate there is data to be processed
341   *	@sk_write_space: callback to indicate there is bf sending space available
342   *	@sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
343   *	@sk_backlog_rcv: callback to process the backlog
344   *	@sk_validate_xmit_skb: ptr to an optional validate function
345   *	@sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
346   *	@sk_reuseport_cb: reuseport group container
347   *	@sk_bpf_storage: ptr to cache and control for bpf_sk_storage
348   *	@sk_rcu: used during RCU grace period
349   *	@sk_freeptr: used for SLAB_TYPESAFE_BY_RCU managed sockets
350   *	@sk_clockid: clockid used by time-based scheduling (SO_TXTIME)
351   *	@sk_txtime_deadline_mode: set deadline mode for SO_TXTIME
352   *	@sk_txtime_report_errors: set report errors mode for SO_TXTIME
353   *	@sk_txtime_unused: unused txtime flags
354   *	@sk_scm_recv_flags: all flags used by scm_recv()
355   *	@sk_scm_credentials: flagged by SO_PASSCRED to recv SCM_CREDENTIALS
356   *	@sk_scm_security: flagged by SO_PASSSEC to recv SCM_SECURITY
357   *	@sk_scm_pidfd: flagged by SO_PASSPIDFD to recv SCM_PIDFD
358   *	@sk_scm_rights: flagged by SO_PASSRIGHTS to recv SCM_RIGHTS
359   *	@sk_scm_pidfd_thread: flagged by SO_PASSPIDFD_THREAD to recv a thread SCM_PIDFD
360   *	@sk_scm_unused: unused flags for scm_recv()
361   *	@ns_tracker: tracker for netns reference
362   *	@sk_user_frags: xarray of pages the user is holding a reference on.
363   *	@sk_owner: reference to the real owner of the socket that calls
364   *		   sock_lock_init_class_and_name().
365   */
366 struct sock {
367 	/*
368 	 * Now struct inet_timewait_sock also uses sock_common, so please just
369 	 * don't add nothing before this first member (__sk_common) --acme
370 	 */
371 	struct sock_common	__sk_common;
372 #define sk_node			__sk_common.skc_node
373 #define sk_nulls_node		__sk_common.skc_nulls_node
374 #define sk_refcnt		__sk_common.skc_refcnt
375 #define sk_tx_queue_mapping	__sk_common.skc_tx_queue_mapping
376 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
377 #define sk_rx_queue_mapping	__sk_common.skc_rx_queue_mapping
378 #endif
379 
380 #define sk_dontcopy_begin	__sk_common.skc_dontcopy_begin
381 #define sk_dontcopy_end		__sk_common.skc_dontcopy_end
382 #define sk_hash			__sk_common.skc_hash
383 #define sk_portpair		__sk_common.skc_portpair
384 #define sk_num			__sk_common.skc_num
385 #define sk_dport		__sk_common.skc_dport
386 #define sk_addrpair		__sk_common.skc_addrpair
387 #define sk_daddr		__sk_common.skc_daddr
388 #define sk_rcv_saddr		__sk_common.skc_rcv_saddr
389 #define sk_family		__sk_common.skc_family
390 #define sk_state		__sk_common.skc_state
391 #define sk_reuse		__sk_common.skc_reuse
392 #define sk_reuseport		__sk_common.skc_reuseport
393 #define sk_ipv6only		__sk_common.skc_ipv6only
394 #define sk_net_refcnt		__sk_common.skc_net_refcnt
395 #define sk_bypass_prot_mem	__sk_common.skc_bypass_prot_mem
396 #define sk_bound_dev_if		__sk_common.skc_bound_dev_if
397 #define sk_bind_node		__sk_common.skc_bind_node
398 #define sk_prot			__sk_common.skc_prot
399 #define sk_net			__sk_common.skc_net
400 #define sk_v6_daddr		__sk_common.skc_v6_daddr
401 #define sk_v6_rcv_saddr	__sk_common.skc_v6_rcv_saddr
402 #define sk_cookie		__sk_common.skc_cookie
403 #define sk_incoming_cpu		__sk_common.skc_incoming_cpu
404 #define sk_flags		__sk_common.skc_flags
405 #define sk_rxhash		__sk_common.skc_rxhash
406 
407 	__cacheline_group_begin(sock_write_rx);
408 
409 	atomic_t		sk_drops;
410 	__s32			sk_peek_off;
411 	struct sk_buff_head	sk_error_queue;
412 	struct sk_buff_head	sk_receive_queue;
413 	/*
414 	 * The backlog queue is special, it is always used with
415 	 * the per-socket spinlock held and requires low latency
416 	 * access. Therefore we special case it's implementation.
417 	 * Note : rmem_alloc is in this structure to fill a hole
418 	 * on 64bit arches, not because its logically part of
419 	 * backlog.
420 	 */
421 	struct {
422 		atomic_t	rmem_alloc;
423 		int		len;
424 		struct sk_buff	*head;
425 		struct sk_buff	*tail;
426 	} sk_backlog;
427 #define sk_rmem_alloc sk_backlog.rmem_alloc
428 
429 	__cacheline_group_end(sock_write_rx);
430 
431 	__cacheline_group_begin(sock_read_rx);
432 	/* early demux fields */
433 	struct dst_entry __rcu	*sk_rx_dst;
434 	int			sk_rx_dst_ifindex;
435 	u32			sk_rx_dst_cookie;
436 
437 #ifdef CONFIG_NET_RX_BUSY_POLL
438 	unsigned int		sk_ll_usec;
439 	unsigned int		sk_napi_id;
440 	u16			sk_busy_poll_budget;
441 	u8			sk_prefer_busy_poll;
442 #endif
443 	u8			sk_userlocks;
444 	int			sk_rcvbuf;
445 
446 	struct sk_filter __rcu	*sk_filter;
447 	union {
448 		struct socket_wq __rcu	*sk_wq;
449 		/* private: */
450 		struct socket_wq	*sk_wq_raw;
451 		/* public: */
452 	};
453 
454 	void			(*sk_data_ready)(struct sock *sk);
455 	long			sk_rcvtimeo;
456 	int			sk_rcvlowat;
457 	__cacheline_group_end(sock_read_rx);
458 
459 	__cacheline_group_begin(sock_read_rxtx);
460 	int			sk_err;
461 	struct socket		*sk_socket;
462 #ifdef CONFIG_MEMCG
463 	struct mem_cgroup	*sk_memcg;
464 #endif
465 #ifdef CONFIG_XFRM
466 	struct xfrm_policy __rcu *sk_policy[2];
467 #endif
468 #if IS_ENABLED(CONFIG_INET_PSP)
469 	struct psp_assoc __rcu	*psp_assoc;
470 #endif
471 	__cacheline_group_end(sock_read_rxtx);
472 
473 	__cacheline_group_begin(sock_write_rxtx);
474 	socket_lock_t		sk_lock;
475 	u32			sk_reserved_mem;
476 	int			sk_forward_alloc;
477 	u32			sk_tsflags;
478 	__cacheline_group_end(sock_write_rxtx);
479 
480 	__cacheline_group_begin(sock_write_tx);
481 	int			sk_write_pending;
482 	atomic_t		sk_omem_alloc;
483 	int			sk_err_soft;
484 
485 	int			sk_wmem_queued;
486 	refcount_t		sk_wmem_alloc;
487 	unsigned long		sk_tsq_flags;
488 	union {
489 		struct sk_buff	*sk_send_head;
490 		struct rb_root	tcp_rtx_queue;
491 	};
492 	struct sk_buff_head	sk_write_queue;
493 	struct page_frag	sk_frag;
494 	union {
495 		struct timer_list	sk_timer;
496 		struct timer_list	tcp_retransmit_timer;
497 		struct timer_list	mptcp_retransmit_timer;
498 	};
499 	unsigned long		sk_pacing_rate; /* bytes per second */
500 	atomic_t		sk_zckey;
501 	atomic_t		sk_tskey;
502 	unsigned long		sk_tx_queue_mapping_jiffies;
503 	__cacheline_group_end(sock_write_tx);
504 
505 	__cacheline_group_begin(sock_read_tx);
506 	u32			sk_dst_pending_confirm;
507 	u32			sk_pacing_status; /* see enum sk_pacing */
508 	unsigned long		sk_max_pacing_rate;
509 	long			sk_sndtimeo;
510 	u32			sk_priority;
511 	u32			sk_mark;
512 	kuid_t			sk_uid;
513 	u16			sk_protocol;
514 	u16			sk_type;
515 	struct dst_entry __rcu	*sk_dst_cache;
516 	netdev_features_t	sk_route_caps;
517 #ifdef CONFIG_SOCK_VALIDATE_XMIT
518 	struct sk_buff*		(*sk_validate_xmit_skb)(struct sock *sk,
519 							struct net_device *dev,
520 							struct sk_buff *skb);
521 #endif
522 	u16			sk_gso_type;
523 	u16			sk_gso_max_segs;
524 	unsigned int		sk_gso_max_size;
525 	gfp_t			sk_allocation;
526 	u32			sk_txhash;
527 	int			sk_sndbuf;
528 	u8			sk_pacing_shift;
529 	bool			sk_use_task_frag;
530 	__cacheline_group_end(sock_read_tx);
531 
532 	/*
533 	 * Because of non atomicity rules, all
534 	 * changes are protected by socket lock.
535 	 */
536 	u8			sk_gso_disabled : 1,
537 				sk_kern_sock : 1,
538 				sk_no_check_tx : 1,
539 				sk_no_check_rx : 1;
540 	u8			sk_shutdown;
541 	unsigned long	        sk_lingertime;
542 	struct proto		*sk_prot_creator;
543 	rwlock_t		sk_callback_lock;
544 	u32			sk_ack_backlog;
545 	u32			sk_max_ack_backlog;
546 	u64			sk_ino;
547 	spinlock_t		sk_peer_lock;
548 	int			sk_bind_phc;
549 	DECLARE_PIDS(sk_peer_pid, PIDTYPE_TGID);
550 	const struct cred	*sk_peer_cred;
551 
552 	ktime_t			sk_stamp;
553 #if BITS_PER_LONG==32
554 	seqlock_t		sk_stamp_seq;
555 #endif
556 	int			sk_disconnects;
557 
558 	union {
559 		u8		sk_txrehash;
560 		u8		sk_scm_recv_flags;
561 		struct {
562 			u8	sk_scm_credentials : 1,
563 				sk_scm_security : 1,
564 				sk_scm_pidfd : 1,
565 				sk_scm_rights : 1,
566 				sk_scm_pidfd_thread : 1,
567 				sk_scm_unused : 3;
568 		};
569 	};
570 	u8			sk_clockid;
571 	u8			sk_txtime_deadline_mode : 1,
572 				sk_txtime_report_errors : 1,
573 				sk_txtime_unused : 6;
574 #define SK_BPF_CB_FLAG_TEST(SK, FLAG) ((SK)->sk_bpf_cb_flags & (FLAG))
575 	u8			sk_bpf_cb_flags;
576 
577 	void			*sk_user_data;
578 #ifdef CONFIG_SECURITY
579 	void			*sk_security;
580 #endif
581 	struct sock_cgroup_data	sk_cgrp_data;
582 	void			(*sk_state_change)(struct sock *sk);
583 	void			(*sk_write_space)(struct sock *sk);
584 	void			(*sk_error_report)(struct sock *sk);
585 	int			(*sk_backlog_rcv)(struct sock *sk,
586 						  struct sk_buff *skb);
587 	void                    (*sk_destruct)(struct sock *sk);
588 	struct sock_reuseport __rcu	*sk_reuseport_cb;
589 #ifdef CONFIG_BPF_SYSCALL
590 	struct bpf_local_storage __rcu	*sk_bpf_storage;
591 #endif
592 	struct numa_drop_counters *sk_drop_counters;
593 	/* sockets using SLAB_TYPESAFE_BY_RCU can use sk_freeptr.
594 	 * By the time kfree() is called, sk_rcu can not be in
595 	 * use and can be mangled.
596 	 */
597 	union {
598 		struct rcu_head	sk_rcu;
599 		freeptr_t	sk_freeptr;
600 	};
601 	netns_tracker		ns_tracker;
602 	struct xarray		sk_user_frags;
603 
604 #if IS_ENABLED(CONFIG_PROVE_LOCKING) && IS_ENABLED(CONFIG_MODULES)
605 	struct module		*sk_owner;
606 #endif
607 };
608 
609 struct sock_bh_locked {
610 	struct sock *sock;
611 	local_lock_t bh_lock;
612 };
613 
614 enum sk_pacing {
615 	SK_PACING_NONE		= 0,
616 	SK_PACING_NEEDED	= 1,
617 	SK_PACING_FQ		= 2,
618 };
619 
620 /* flag bits in sk_user_data
621  *
622  * - SK_USER_DATA_NOCOPY:      Pointer stored in sk_user_data might
623  *   not be suitable for copying when cloning the socket. For instance,
624  *   it can point to a reference counted object. sk_user_data bottom
625  *   bit is set if pointer must not be copied.
626  *
627  * - SK_USER_DATA_BPF:         Mark whether sk_user_data field is
628  *   managed/owned by a BPF reuseport array. This bit should be set
629  *   when sk_user_data's sk is added to the bpf's reuseport_array.
630  *
631  * - SK_USER_DATA_PSOCK:       Mark whether pointer stored in
632  *   sk_user_data points to psock type. This bit should be set
633  *   when sk_user_data is assigned to a psock object.
634  */
635 #define SK_USER_DATA_NOCOPY	1UL
636 #define SK_USER_DATA_BPF	2UL
637 #define SK_USER_DATA_PSOCK	4UL
638 #define SK_USER_DATA_PTRMASK	~(SK_USER_DATA_NOCOPY | SK_USER_DATA_BPF |\
639 				  SK_USER_DATA_PSOCK)
640 
641 /**
642  * sk_user_data_is_nocopy - Test if sk_user_data pointer must not be copied
643  * @sk: socket
644  */
645 static inline bool sk_user_data_is_nocopy(const struct sock *sk)
646 {
647 	return ((uintptr_t)sk->sk_user_data & SK_USER_DATA_NOCOPY);
648 }
649 
650 #define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data)))
651 
652 /**
653  * __locked_read_sk_user_data_with_flags - return the pointer
654  * only if argument flags all has been set in sk_user_data. Otherwise
655  * return NULL
656  *
657  * @sk: socket
658  * @flags: flag bits
659  *
660  * The caller must be holding sk->sk_callback_lock.
661  */
662 static inline void *
663 __locked_read_sk_user_data_with_flags(const struct sock *sk,
664 				      uintptr_t flags)
665 {
666 	uintptr_t sk_user_data =
667 		(uintptr_t)rcu_dereference_check(__sk_user_data(sk),
668 						 lockdep_is_held(&sk->sk_callback_lock));
669 
670 	WARN_ON_ONCE(flags & SK_USER_DATA_PTRMASK);
671 
672 	if ((sk_user_data & flags) == flags)
673 		return (void *)(sk_user_data & SK_USER_DATA_PTRMASK);
674 	return NULL;
675 }
676 
677 /**
678  * __rcu_dereference_sk_user_data_with_flags - return the pointer
679  * only if argument flags all has been set in sk_user_data. Otherwise
680  * return NULL
681  *
682  * @sk: socket
683  * @flags: flag bits
684  */
685 static inline void *
686 __rcu_dereference_sk_user_data_with_flags(const struct sock *sk,
687 					  uintptr_t flags)
688 {
689 	uintptr_t sk_user_data = (uintptr_t)rcu_dereference(__sk_user_data(sk));
690 
691 	WARN_ON_ONCE(flags & SK_USER_DATA_PTRMASK);
692 
693 	if ((sk_user_data & flags) == flags)
694 		return (void *)(sk_user_data & SK_USER_DATA_PTRMASK);
695 	return NULL;
696 }
697 
698 #define rcu_dereference_sk_user_data(sk)				\
699 	__rcu_dereference_sk_user_data_with_flags(sk, 0)
700 #define __rcu_assign_sk_user_data_with_flags(sk, ptr, flags)		\
701 ({									\
702 	uintptr_t __tmp1 = (uintptr_t)(ptr),				\
703 		  __tmp2 = (uintptr_t)(flags);				\
704 	WARN_ON_ONCE(__tmp1 & ~SK_USER_DATA_PTRMASK);			\
705 	WARN_ON_ONCE(__tmp2 & SK_USER_DATA_PTRMASK);			\
706 	rcu_assign_pointer(__sk_user_data((sk)),			\
707 			   __tmp1 | __tmp2);				\
708 })
709 #define rcu_assign_sk_user_data(sk, ptr)				\
710 	__rcu_assign_sk_user_data_with_flags(sk, ptr, 0)
711 
712 static inline
713 struct net *sock_net(const struct sock *sk)
714 {
715 	return read_pnet(&sk->sk_net);
716 }
717 
718 static inline
719 void sock_net_set(struct sock *sk, struct net *net)
720 {
721 	write_pnet(&sk->sk_net, net);
722 }
723 
724 /*
725  * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK
726  * or not whether his port will be reused by someone else. SK_FORCE_REUSE
727  * on a socket means that the socket will reuse everybody else's port
728  * without looking at the other's sk_reuse value.
729  */
730 
731 #define SK_NO_REUSE	0
732 #define SK_CAN_REUSE	1
733 #define SK_FORCE_REUSE	2
734 
735 int sk_set_peek_off(struct sock *sk, int val);
736 
737 static inline int sk_peek_offset(const struct sock *sk, int flags)
738 {
739 	if (unlikely(flags & MSG_PEEK)) {
740 		return READ_ONCE(sk->sk_peek_off);
741 	}
742 
743 	return 0;
744 }
745 
746 static inline void sk_peek_offset_bwd(struct sock *sk, int val)
747 {
748 	s32 off = READ_ONCE(sk->sk_peek_off);
749 
750 	if (unlikely(off >= 0)) {
751 		off = max_t(s32, off - val, 0);
752 		WRITE_ONCE(sk->sk_peek_off, off);
753 	}
754 }
755 
756 static inline void sk_peek_offset_fwd(struct sock *sk, int val)
757 {
758 	sk_peek_offset_bwd(sk, -val);
759 }
760 
761 /*
762  * Hashed lists helper routines
763  */
764 static inline struct sock *sk_entry(const struct hlist_node *node)
765 {
766 	return hlist_entry(node, struct sock, sk_node);
767 }
768 
769 static inline struct sock *__sk_head(const struct hlist_head *head)
770 {
771 	return hlist_entry(head->first, struct sock, sk_node);
772 }
773 
774 static inline struct sock *sk_head(const struct hlist_head *head)
775 {
776 	return hlist_empty(head) ? NULL : __sk_head(head);
777 }
778 
779 static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head)
780 {
781 	return hlist_nulls_entry(head->first, struct sock, sk_nulls_node);
782 }
783 
784 static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head)
785 {
786 	return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head);
787 }
788 
789 static inline struct sock *sk_next(const struct sock *sk)
790 {
791 	return hlist_entry_safe(sk->sk_node.next, struct sock, sk_node);
792 }
793 
794 static inline struct sock *sk_nulls_next(const struct sock *sk)
795 {
796 	return (!is_a_nulls(sk->sk_nulls_node.next)) ?
797 		hlist_nulls_entry(sk->sk_nulls_node.next,
798 				  struct sock, sk_nulls_node) :
799 		NULL;
800 }
801 
802 static inline bool sk_unhashed(const struct sock *sk)
803 {
804 	return hlist_unhashed(&sk->sk_node);
805 }
806 
807 static inline bool sk_hashed(const struct sock *sk)
808 {
809 	return !sk_unhashed(sk);
810 }
811 
812 static inline void sk_node_init(struct hlist_node *node)
813 {
814 	node->pprev = NULL;
815 }
816 
817 static inline void __sk_del_node(struct sock *sk)
818 {
819 	__hlist_del(&sk->sk_node);
820 }
821 
822 /* NB: equivalent to hlist_del_init_rcu */
823 static inline bool __sk_del_node_init(struct sock *sk)
824 {
825 	if (sk_hashed(sk)) {
826 		__sk_del_node(sk);
827 		sk_node_init(&sk->sk_node);
828 		return true;
829 	}
830 	return false;
831 }
832 
833 /* Grab socket reference count. This operation is valid only
834    when sk is ALREADY grabbed f.e. it is found in hash table
835    or a list and the lookup is made under lock preventing hash table
836    modifications.
837  */
838 
839 static __always_inline void sock_hold(struct sock *sk)
840 {
841 	refcount_inc(&sk->sk_refcnt);
842 }
843 
844 /* Ungrab socket in the context, which assumes that socket refcnt
845    cannot hit zero, f.e. it is true in context of any socketcall.
846  */
847 static __always_inline void __sock_put(struct sock *sk)
848 {
849 	refcount_dec(&sk->sk_refcnt);
850 }
851 
852 static inline bool sk_del_node_init(struct sock *sk)
853 {
854 	bool rc = __sk_del_node_init(sk);
855 
856 	if (rc)
857 		__sock_put(sk);
858 
859 	return rc;
860 }
861 #define sk_del_node_init_rcu(sk)	sk_del_node_init(sk)
862 
863 static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk)
864 {
865 	if (sk_hashed(sk)) {
866 		hlist_nulls_del_init_rcu(&sk->sk_nulls_node);
867 		return true;
868 	}
869 	return false;
870 }
871 
872 static inline bool sk_nulls_del_node_init_rcu(struct sock *sk)
873 {
874 	bool rc = __sk_nulls_del_node_init_rcu(sk);
875 
876 	if (rc)
877 		__sock_put(sk);
878 
879 	return rc;
880 }
881 
882 static inline bool sk_nulls_replace_node_init_rcu(struct sock *old,
883 						  struct sock *new)
884 {
885 	if (sk_hashed(old)) {
886 		hlist_nulls_replace_init_rcu(&old->sk_nulls_node,
887 					     &new->sk_nulls_node);
888 		__sock_put(old);
889 		return true;
890 	}
891 
892 	return false;
893 }
894 
895 static inline void __sk_add_node(struct sock *sk, struct hlist_head *list)
896 {
897 	hlist_add_head(&sk->sk_node, list);
898 }
899 
900 static inline void sk_add_node(struct sock *sk, struct hlist_head *list)
901 {
902 	sock_hold(sk);
903 	__sk_add_node(sk, list);
904 }
905 
906 static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list)
907 {
908 	sock_hold(sk);
909 	if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport &&
910 	    sk->sk_family == AF_INET6)
911 		hlist_add_tail_rcu(&sk->sk_node, list);
912 	else
913 		hlist_add_head_rcu(&sk->sk_node, list);
914 }
915 
916 static inline void sk_add_node_tail_rcu(struct sock *sk, struct hlist_head *list)
917 {
918 	sock_hold(sk);
919 	hlist_add_tail_rcu(&sk->sk_node, list);
920 }
921 
922 static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
923 {
924 	hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list);
925 }
926 
927 static inline void __sk_nulls_add_node_tail_rcu(struct sock *sk, struct hlist_nulls_head *list)
928 {
929 	hlist_nulls_add_tail_rcu(&sk->sk_nulls_node, list);
930 }
931 
932 static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
933 {
934 	sock_hold(sk);
935 	__sk_nulls_add_node_rcu(sk, list);
936 }
937 
938 static inline void __sk_del_bind_node(struct sock *sk)
939 {
940 	__hlist_del(&sk->sk_bind_node);
941 }
942 
943 static inline void sk_add_bind_node(struct sock *sk,
944 					struct hlist_head *list)
945 {
946 	hlist_add_head(&sk->sk_bind_node, list);
947 }
948 
949 #define sk_for_each(__sk, list) \
950 	hlist_for_each_entry(__sk, list, sk_node)
951 #define sk_for_each_rcu(__sk, list) \
952 	hlist_for_each_entry_rcu(__sk, list, sk_node)
953 #define sk_nulls_for_each(__sk, node, list) \
954 	hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)
955 #define sk_nulls_for_each_rcu(__sk, node, list) \
956 	hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)
957 #define sk_for_each_from(__sk) \
958 	hlist_for_each_entry_from(__sk, sk_node)
959 #define sk_nulls_for_each_from(__sk, node) \
960 	if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \
961 		hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node)
962 #define sk_for_each_safe(__sk, tmp, list) \
963 	hlist_for_each_entry_safe(__sk, tmp, list, sk_node)
964 #define sk_for_each_bound(__sk, list) \
965 	hlist_for_each_entry(__sk, list, sk_bind_node)
966 #define sk_for_each_bound_safe(__sk, tmp, list) \
967 	hlist_for_each_entry_safe(__sk, tmp, list, sk_bind_node)
968 
969 /**
970  * sk_for_each_entry_offset_rcu - iterate over a list at a given struct offset
971  * @tpos:	the type * to use as a loop cursor.
972  * @pos:	the &struct hlist_node to use as a loop cursor.
973  * @head:	the head for your list.
974  * @offset:	offset of hlist_node within the struct.
975  *
976  */
977 #define sk_for_each_entry_offset_rcu(tpos, pos, head, offset)		       \
978 	for (pos = rcu_dereference(hlist_first_rcu(head));		       \
979 	     pos != NULL &&						       \
980 		({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;});       \
981 	     pos = rcu_dereference(hlist_next_rcu(pos)))
982 
983 static inline struct user_namespace *sk_user_ns(const struct sock *sk)
984 {
985 	/* Careful only use this in a context where these parameters
986 	 * can not change and must all be valid, such as recvmsg from
987 	 * userspace.
988 	 */
989 	return sk->sk_socket->file->f_cred->user_ns;
990 }
991 
992 /* Sock flags */
993 enum sock_flags {
994 	SOCK_DEAD,
995 	SOCK_DONE,
996 	SOCK_URGINLINE,
997 	SOCK_KEEPOPEN,
998 	SOCK_LINGER,
999 	SOCK_DESTROY,
1000 	SOCK_BROADCAST,
1001 	SOCK_TIMESTAMP,
1002 	SOCK_ZAPPED,
1003 	SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */
1004 	SOCK_DBG, /* %SO_DEBUG setting */
1005 	SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
1006 	SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */
1007 	SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
1008 	SOCK_MEMALLOC, /* VM depends on this socket for swapping */
1009 	SOCK_TIMESTAMPING_RX_SOFTWARE,  /* %SOF_TIMESTAMPING_RX_SOFTWARE */
1010 	SOCK_FASYNC, /* fasync() active */
1011 	SOCK_RXQ_OVFL,
1012 	SOCK_ZEROCOPY, /* buffers from userspace */
1013 	SOCK_WIFI_STATUS, /* push wifi status to userspace */
1014 	SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS.
1015 		     * Will use last 4 bytes of packet sent from
1016 		     * user-space instead.
1017 		     */
1018 	SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */
1019 	SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */
1020 	SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */
1021 	SOCK_TXTIME,
1022 	SOCK_XDP, /* XDP is attached */
1023 	SOCK_TSTAMP_NEW, /* Indicates 64 bit timestamps always */
1024 	SOCK_RCVMARK, /* Receive SO_MARK  ancillary data with packet */
1025 	SOCK_RCVPRIORITY, /* Receive SO_PRIORITY ancillary data with packet */
1026 	SOCK_TIMESTAMPING_ANY, /* Copy of sk_tsflags & TSFLAGS_ANY */
1027 };
1028 
1029 #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))
1030 /*
1031  * The highest bit of sk_tsflags is reserved for kernel-internal
1032  * SOCKCM_FLAG_TS_OPT_ID. There is a check in core/sock.c to control that
1033  * SOF_TIMESTAMPING* values do not reach this reserved area
1034  */
1035 #define SOCKCM_FLAG_TS_OPT_ID	BIT(31)
1036 
1037 static inline void sock_copy_flags(struct sock *nsk, const struct sock *osk)
1038 {
1039 	nsk->sk_flags = osk->sk_flags;
1040 }
1041 
1042 static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
1043 {
1044 	__set_bit(flag, &sk->sk_flags);
1045 }
1046 
1047 static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag)
1048 {
1049 	__clear_bit(flag, &sk->sk_flags);
1050 }
1051 
1052 static inline void sock_valbool_flag(struct sock *sk, enum sock_flags bit,
1053 				     int valbool)
1054 {
1055 	if (valbool)
1056 		sock_set_flag(sk, bit);
1057 	else
1058 		sock_reset_flag(sk, bit);
1059 }
1060 
1061 static inline bool sock_flag(const struct sock *sk, enum sock_flags flag)
1062 {
1063 	return test_bit(flag, &sk->sk_flags);
1064 }
1065 
1066 #ifdef CONFIG_NET
1067 DECLARE_STATIC_KEY_FALSE(memalloc_socks_key);
1068 static inline int sk_memalloc_socks(void)
1069 {
1070 	return static_branch_unlikely(&memalloc_socks_key);
1071 }
1072 
1073 void __receive_sock(struct file *file);
1074 #else
1075 
1076 static inline int sk_memalloc_socks(void)
1077 {
1078 	return 0;
1079 }
1080 
1081 static inline void __receive_sock(struct file *file)
1082 { }
1083 #endif
1084 
1085 static inline gfp_t sk_gfp_mask(const struct sock *sk, gfp_t gfp_mask)
1086 {
1087 	return gfp_mask | (sk->sk_allocation & __GFP_MEMALLOC);
1088 }
1089 
1090 static inline void sk_acceptq_removed(struct sock *sk)
1091 {
1092 	WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog - 1);
1093 }
1094 
1095 static inline void sk_acceptq_added(struct sock *sk)
1096 {
1097 	WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog + 1);
1098 }
1099 
1100 /* Note: If you think the test should be:
1101  *	return READ_ONCE(sk->sk_ack_backlog) >= READ_ONCE(sk->sk_max_ack_backlog);
1102  * Then please take a look at commit 64a146513f8f ("[NET]: Revert incorrect accept queue backlog changes.")
1103  */
1104 static inline bool sk_acceptq_is_full(const struct sock *sk)
1105 {
1106 	return READ_ONCE(sk->sk_ack_backlog) > READ_ONCE(sk->sk_max_ack_backlog);
1107 }
1108 
1109 /*
1110  * Compute minimal free write space needed to queue new packets.
1111  */
1112 static inline int sk_stream_min_wspace(const struct sock *sk)
1113 {
1114 	return READ_ONCE(sk->sk_wmem_queued) >> 1;
1115 }
1116 
1117 static inline int sk_stream_wspace(const struct sock *sk)
1118 {
1119 	return READ_ONCE(sk->sk_sndbuf) - READ_ONCE(sk->sk_wmem_queued);
1120 }
1121 
1122 static inline void sk_wmem_queued_add(struct sock *sk, int val)
1123 {
1124 	WRITE_ONCE(sk->sk_wmem_queued, sk->sk_wmem_queued + val);
1125 }
1126 
1127 static inline void sk_forward_alloc_add(struct sock *sk, int val)
1128 {
1129 	/* Paired with lockless reads of sk->sk_forward_alloc */
1130 	WRITE_ONCE(sk->sk_forward_alloc, sk->sk_forward_alloc + val);
1131 }
1132 
1133 void sk_stream_write_space(struct sock *sk);
1134 void sk_set_nospace(struct sock *sk);
1135 void sk_clear_nospace(struct sock *sk);
1136 
1137 /* OOB backlog add */
1138 static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
1139 {
1140 	/* dont let skb dst not refcounted, we are going to leave rcu lock */
1141 	skb_dst_force(skb);
1142 
1143 	if (!sk->sk_backlog.tail)
1144 		WRITE_ONCE(sk->sk_backlog.head, skb);
1145 	else
1146 		sk->sk_backlog.tail->next = skb;
1147 
1148 	WRITE_ONCE(sk->sk_backlog.tail, skb);
1149 	skb->next = NULL;
1150 }
1151 
1152 /*
1153  * Take into account size of receive queue and backlog queue
1154  * Do not take into account this skb truesize,
1155  * to allow even a single big packet to come.
1156  */
1157 static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit)
1158 {
1159 	unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc);
1160 
1161 	return qsize > limit;
1162 }
1163 
1164 /* The per-socket spinlock must be held here. */
1165 static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb,
1166 					      unsigned int limit)
1167 {
1168 	if (sk_rcvqueues_full(sk, limit))
1169 		return -ENOBUFS;
1170 
1171 	/*
1172 	 * If the skb was allocated from pfmemalloc reserves, only
1173 	 * allow SOCK_MEMALLOC sockets to use it as this socket is
1174 	 * helping free memory
1175 	 */
1176 	if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC))
1177 		return -ENOMEM;
1178 
1179 	__sk_add_backlog(sk, skb);
1180 	sk->sk_backlog.len += skb->truesize;
1181 	return 0;
1182 }
1183 
1184 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb);
1185 
1186 INDIRECT_CALLABLE_DECLARE(int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb));
1187 INDIRECT_CALLABLE_DECLARE(int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb));
1188 
1189 static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
1190 {
1191 	if (sk_memalloc_socks() && skb_pfmemalloc(skb))
1192 		return __sk_backlog_rcv(sk, skb);
1193 
1194 	return INDIRECT_CALL_INET(sk->sk_backlog_rcv,
1195 				  tcp_v6_do_rcv,
1196 				  tcp_v4_do_rcv,
1197 				  sk, skb);
1198 }
1199 
1200 static inline void sk_incoming_cpu_update(struct sock *sk)
1201 {
1202 	int cpu = raw_smp_processor_id();
1203 
1204 	if (unlikely(READ_ONCE(sk->sk_incoming_cpu) != cpu))
1205 		WRITE_ONCE(sk->sk_incoming_cpu, cpu);
1206 }
1207 
1208 
1209 static inline void sock_rps_save_rxhash(struct sock *sk,
1210 					const struct sk_buff *skb)
1211 {
1212 #ifdef CONFIG_RPS
1213 	/* The following WRITE_ONCE() is paired with the READ_ONCE()
1214 	 * here, and another one in sock_rps_record_flow().
1215 	 */
1216 	if (unlikely(READ_ONCE(sk->sk_rxhash) != skb->hash))
1217 		WRITE_ONCE(sk->sk_rxhash, skb->hash);
1218 #endif
1219 }
1220 
1221 static inline void sock_rps_reset_rxhash(struct sock *sk)
1222 {
1223 #ifdef CONFIG_RPS
1224 	/* Paired with READ_ONCE() in sock_rps_record_flow() */
1225 	WRITE_ONCE(sk->sk_rxhash, 0);
1226 #endif
1227 }
1228 
1229 #define sk_wait_event(__sk, __timeo, __condition, __wait)		\
1230 	({	int __rc, __dis = __sk->sk_disconnects;			\
1231 		release_sock(__sk);					\
1232 		__rc = __condition;					\
1233 		if (!__rc) {						\
1234 			*(__timeo) = wait_woken(__wait,			\
1235 						TASK_INTERRUPTIBLE,	\
1236 						*(__timeo));		\
1237 		}							\
1238 		sched_annotate_sleep();					\
1239 		lock_sock(__sk);					\
1240 		__rc = __dis == __sk->sk_disconnects ? __condition : -EPIPE; \
1241 		__rc;							\
1242 	})
1243 
1244 int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
1245 int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
1246 void sk_stream_wait_close(struct sock *sk, long timeo_p);
1247 int sk_stream_error(struct sock *sk, int flags, int err);
1248 void sk_stream_kill_queues(struct sock *sk);
1249 void sk_set_memalloc(struct sock *sk);
1250 void sk_clear_memalloc(struct sock *sk);
1251 
1252 void __sk_flush_backlog(struct sock *sk);
1253 
1254 static inline bool sk_flush_backlog(struct sock *sk)
1255 {
1256 	if (unlikely(READ_ONCE(sk->sk_backlog.tail))) {
1257 		__sk_flush_backlog(sk);
1258 		return true;
1259 	}
1260 	return false;
1261 }
1262 
1263 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb);
1264 
1265 struct request_sock_ops;
1266 struct timewait_sock_ops;
1267 struct inet_hashinfo;
1268 struct raw_hashinfo;
1269 struct smc_hashinfo;
1270 struct module;
1271 struct sk_psock;
1272 
1273 /*
1274  * caches using SLAB_TYPESAFE_BY_RCU should let .next pointer from nulls nodes
1275  * un-modified. Special care is taken when initializing object to zero.
1276  */
1277 static inline void sk_prot_clear_nulls(struct sock *sk, int size)
1278 {
1279 	if (offsetof(struct sock, sk_node.next) != 0)
1280 		memset(sk, 0, offsetof(struct sock, sk_node.next));
1281 	memset(&sk->sk_node.pprev, 0,
1282 	       size - offsetof(struct sock, sk_node.pprev));
1283 }
1284 
1285 struct proto_accept_arg {
1286 	int flags;
1287 	int err;
1288 	int is_empty;
1289 	bool kern;
1290 };
1291 
1292 /* Networking protocol blocks we attach to sockets.
1293  * socket layer -> transport layer interface
1294  */
1295 struct proto {
1296 	void			(*close)(struct sock *sk,
1297 					long timeout);
1298 	int			(*pre_connect)(struct sock *sk,
1299 					struct sockaddr_unsized *uaddr,
1300 					int addr_len);
1301 	int			(*connect)(struct sock *sk,
1302 					struct sockaddr_unsized *uaddr,
1303 					int addr_len);
1304 	int			(*disconnect)(struct sock *sk, int flags);
1305 
1306 	struct sock *		(*accept)(struct sock *sk,
1307 					  struct proto_accept_arg *arg);
1308 
1309 	int			(*ioctl)(struct sock *sk, int cmd,
1310 					 int *karg);
1311 	int			(*init)(struct sock *sk);
1312 	void			(*destroy)(struct sock *sk);
1313 	void			(*shutdown)(struct sock *sk, int how);
1314 	int			(*setsockopt)(struct sock *sk, int level,
1315 					int optname, sockptr_t optval,
1316 					unsigned int optlen);
1317 	int			(*getsockopt)(struct sock *sk, int level,
1318 					int optname, char __user *optval,
1319 					int __user *option);
1320 	void			(*keepalive)(struct sock *sk, int valbool);
1321 #ifdef CONFIG_COMPAT
1322 	int			(*compat_ioctl)(struct sock *sk,
1323 					unsigned int cmd, unsigned long arg);
1324 #endif
1325 	int			(*sendmsg)(struct sock *sk, struct msghdr *msg,
1326 					   size_t len);
1327 	int			(*recvmsg)(struct sock *sk, struct msghdr *msg,
1328 					   size_t len, int flags);
1329 	void			(*splice_eof)(struct socket *sock);
1330 	int			(*bind)(struct sock *sk,
1331 					struct sockaddr_unsized *addr, int addr_len);
1332 	int			(*bind_add)(struct sock *sk,
1333 					struct sockaddr_unsized *addr, int addr_len);
1334 
1335 	int			(*backlog_rcv) (struct sock *sk,
1336 						struct sk_buff *skb);
1337 	bool			(*bpf_bypass_getsockopt)(int level,
1338 							 int optname);
1339 
1340 	void		(*release_cb)(struct sock *sk);
1341 
1342 	/* Keeping track of sk's, looking them up, and port selection methods. */
1343 	int			(*hash)(struct sock *sk);
1344 	void			(*unhash)(struct sock *sk);
1345 	void			(*rehash)(struct sock *sk);
1346 	int			(*get_port)(struct sock *sk, unsigned short snum);
1347 	void			(*put_port)(struct sock *sk);
1348 #ifdef CONFIG_BPF_SYSCALL
1349 	int			(*psock_update_sk_prot)(struct sock *sk,
1350 							struct sk_psock *psock,
1351 							bool restore);
1352 #endif
1353 
1354 	/* Keeping track of sockets in use */
1355 #ifdef CONFIG_PROC_FS
1356 	unsigned int		inuse_idx;
1357 #endif
1358 
1359 	bool			(*stream_memory_free)(const struct sock *sk, int wake);
1360 	bool			(*sock_is_readable)(struct sock *sk);
1361 	/* Memory pressure */
1362 	void			(*enter_memory_pressure)(struct sock *sk);
1363 	void			(*leave_memory_pressure)(struct sock *sk);
1364 	atomic_long_t		*memory_allocated;	/* Current allocated memory. */
1365 	int  __percpu		*per_cpu_fw_alloc;
1366 	struct percpu_counter	*sockets_allocated;	/* Current number of sockets. */
1367 
1368 	/*
1369 	 * Pressure flag: try to collapse.
1370 	 * Technical note: it is used by multiple contexts non atomically.
1371 	 * Make sure to use READ_ONCE()/WRITE_ONCE() for all reads/writes.
1372 	 * All the __sk_mem_schedule() is of this nature: accounting
1373 	 * is strict, actions are advisory and have some latency.
1374 	 */
1375 	unsigned long		*memory_pressure;
1376 	long			*sysctl_mem;
1377 
1378 	int			*sysctl_wmem;
1379 	int			*sysctl_rmem;
1380 	u32			sysctl_wmem_offset;
1381 	u32			sysctl_rmem_offset;
1382 
1383 	int			max_header;
1384 	bool			no_autobind;
1385 
1386 	struct kmem_cache	*slab;
1387 	unsigned int		obj_size;
1388 	unsigned int		freeptr_offset;
1389 	unsigned int		ipv6_pinfo_offset;
1390 	slab_flags_t		slab_flags;
1391 	unsigned int		useroffset;	/* Usercopy region offset */
1392 	unsigned int		usersize;	/* Usercopy region size */
1393 
1394 	struct request_sock_ops	*rsk_prot;
1395 	struct timewait_sock_ops *twsk_prot;
1396 
1397 	union {
1398 		struct inet_hashinfo	*hashinfo;
1399 		struct raw_hashinfo	*raw_hash;
1400 		struct smc_hashinfo	*smc_hash;
1401 	} h;
1402 
1403 	struct module		*owner;
1404 
1405 	char			name[32];
1406 
1407 	struct list_head	node;
1408 	int			(*diag_destroy)(struct sock *sk, int err);
1409 } __randomize_layout;
1410 
1411 int proto_register(struct proto *prot, int alloc_slab);
1412 void proto_unregister(struct proto *prot);
1413 int sock_load_diag_module(int family, int protocol);
1414 
1415 INDIRECT_CALLABLE_DECLARE(bool tcp_stream_memory_free(const struct sock *sk, int wake));
1416 
1417 static inline bool __sk_stream_memory_free(const struct sock *sk, int wake)
1418 {
1419 	if (READ_ONCE(sk->sk_wmem_queued) >= READ_ONCE(sk->sk_sndbuf))
1420 		return false;
1421 
1422 	return sk->sk_prot->stream_memory_free ?
1423 		INDIRECT_CALL_INET_1(sk->sk_prot->stream_memory_free,
1424 				     tcp_stream_memory_free, sk, wake) : true;
1425 }
1426 
1427 static inline bool sk_stream_memory_free(const struct sock *sk)
1428 {
1429 	return __sk_stream_memory_free(sk, 0);
1430 }
1431 
1432 static inline bool __sk_stream_is_writeable(const struct sock *sk, int wake)
1433 {
1434 	return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) &&
1435 	       __sk_stream_memory_free(sk, wake);
1436 }
1437 
1438 static inline bool sk_stream_is_writeable(const struct sock *sk)
1439 {
1440 	return __sk_stream_is_writeable(sk, 0);
1441 }
1442 
1443 static inline int sk_under_cgroup_hierarchy(struct sock *sk,
1444 					    struct cgroup *ancestor)
1445 {
1446 #ifdef CONFIG_SOCK_CGROUP_DATA
1447 	return cgroup_is_descendant(sock_cgroup_ptr(&sk->sk_cgrp_data),
1448 				    ancestor);
1449 #else
1450 	return -ENOTSUPP;
1451 #endif
1452 }
1453 
1454 #define SK_ALLOC_PERCPU_COUNTER_BATCH 16
1455 
1456 static inline void sk_sockets_allocated_dec(struct sock *sk)
1457 {
1458 	percpu_counter_add_batch(sk->sk_prot->sockets_allocated, -1,
1459 				 SK_ALLOC_PERCPU_COUNTER_BATCH);
1460 }
1461 
1462 static inline void sk_sockets_allocated_inc(struct sock *sk)
1463 {
1464 	percpu_counter_add_batch(sk->sk_prot->sockets_allocated, 1,
1465 				 SK_ALLOC_PERCPU_COUNTER_BATCH);
1466 }
1467 
1468 static inline u64
1469 sk_sockets_allocated_read_positive(struct sock *sk)
1470 {
1471 	return percpu_counter_read_positive(sk->sk_prot->sockets_allocated);
1472 }
1473 
1474 static inline int
1475 proto_sockets_allocated_sum_positive(struct proto *prot)
1476 {
1477 	return percpu_counter_sum_positive(prot->sockets_allocated);
1478 }
1479 
1480 #ifdef CONFIG_PROC_FS
1481 #define PROTO_INUSE_NR	64	/* should be enough for the first time */
1482 struct prot_inuse {
1483 	int all;
1484 	int val[PROTO_INUSE_NR];
1485 };
1486 
1487 static inline void sock_prot_inuse_add(const struct net *net,
1488 				       const struct proto *prot, int val)
1489 {
1490 	this_cpu_add(net->core.prot_inuse->val[prot->inuse_idx], val);
1491 }
1492 
1493 static inline void sock_inuse_add(const struct net *net, int val)
1494 {
1495 	this_cpu_add(net->core.prot_inuse->all, val);
1496 }
1497 
1498 int sock_prot_inuse_get(struct net *net, struct proto *proto);
1499 int sock_inuse_get(struct net *net);
1500 #else
1501 static inline void sock_prot_inuse_add(const struct net *net,
1502 				       const struct proto *prot, int val)
1503 {
1504 }
1505 
1506 static inline void sock_inuse_add(const struct net *net, int val)
1507 {
1508 }
1509 #endif
1510 
1511 
1512 /* With per-bucket locks this operation is not-atomic, so that
1513  * this version is not worse.
1514  */
1515 static inline int __sk_prot_rehash(struct sock *sk)
1516 {
1517 	sk->sk_prot->unhash(sk);
1518 	return sk->sk_prot->hash(sk);
1519 }
1520 
1521 /* About 10 seconds */
1522 #define SOCK_DESTROY_TIME (10*HZ)
1523 
1524 /* Sockets 0-1023 can't be bound to unless you are superuser */
1525 #define PROT_SOCK	1024
1526 
1527 #define SHUTDOWN_MASK	3
1528 #define RCV_SHUTDOWN	1
1529 #define SEND_SHUTDOWN	2
1530 
1531 #define SOCK_BINDADDR_LOCK	4
1532 #define SOCK_BINDPORT_LOCK	8
1533 /**
1534  * define SOCK_CONNECT_BIND - &sock->sk_userlocks flag for auto-bind at connect() time
1535  */
1536 #define SOCK_CONNECT_BIND	16
1537 
1538 struct socket_alloc {
1539 	struct socket socket;
1540 	struct inode vfs_inode;
1541 };
1542 
1543 static inline struct socket *SOCKET_I(struct inode *inode)
1544 {
1545 	return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
1546 }
1547 
1548 static inline struct inode *SOCK_INODE(struct socket *socket)
1549 {
1550 	return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
1551 }
1552 
1553 /*
1554  * Functions for memory accounting
1555  */
1556 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind);
1557 int __sk_mem_schedule(struct sock *sk, int size, int kind);
1558 void __sk_mem_reduce_allocated(struct sock *sk, int amount);
1559 void __sk_mem_reclaim(struct sock *sk, int amount);
1560 
1561 #define SK_MEM_SEND	0
1562 #define SK_MEM_RECV	1
1563 
1564 /* sysctl_mem values are in pages */
1565 static inline long sk_prot_mem_limits(const struct sock *sk, int index)
1566 {
1567 	return READ_ONCE(sk->sk_prot->sysctl_mem[index]);
1568 }
1569 
1570 static inline int sk_mem_pages(int amt)
1571 {
1572 	return (amt + PAGE_SIZE - 1) >> PAGE_SHIFT;
1573 }
1574 
1575 static inline bool sk_has_account(struct sock *sk)
1576 {
1577 	/* return true if protocol supports memory accounting */
1578 	return !!sk->sk_prot->memory_allocated;
1579 }
1580 
1581 static inline bool sk_wmem_schedule(struct sock *sk, int size)
1582 {
1583 	int delta;
1584 
1585 	if (!sk_has_account(sk))
1586 		return true;
1587 	delta = size - sk->sk_forward_alloc;
1588 	return delta <= 0 || __sk_mem_schedule(sk, delta, SK_MEM_SEND);
1589 }
1590 
1591 static inline bool
1592 __sk_rmem_schedule(struct sock *sk, int size, bool pfmemalloc)
1593 {
1594 	int delta;
1595 
1596 	if (!sk_has_account(sk))
1597 		return true;
1598 	delta = size - sk->sk_forward_alloc;
1599 	return delta <= 0 || __sk_mem_schedule(sk, delta, SK_MEM_RECV) ||
1600 	       pfmemalloc;
1601 }
1602 
1603 static inline bool
1604 sk_rmem_schedule(struct sock *sk, const struct sk_buff *skb, int size)
1605 {
1606 	return __sk_rmem_schedule(sk, size, skb_pfmemalloc(skb));
1607 }
1608 
1609 static inline int sk_unused_reserved_mem(const struct sock *sk)
1610 {
1611 	int unused_mem;
1612 
1613 	if (likely(!sk->sk_reserved_mem))
1614 		return 0;
1615 
1616 	unused_mem = sk->sk_reserved_mem - sk->sk_wmem_queued -
1617 			atomic_read(&sk->sk_rmem_alloc);
1618 
1619 	return unused_mem > 0 ? unused_mem : 0;
1620 }
1621 
1622 static inline void sk_mem_reclaim(struct sock *sk)
1623 {
1624 	int reclaimable;
1625 
1626 	if (!sk_has_account(sk))
1627 		return;
1628 
1629 	reclaimable = sk->sk_forward_alloc - sk_unused_reserved_mem(sk);
1630 
1631 	if (reclaimable >= (int)PAGE_SIZE)
1632 		__sk_mem_reclaim(sk, reclaimable);
1633 }
1634 
1635 static inline void sk_mem_reclaim_final(struct sock *sk)
1636 {
1637 	sk->sk_reserved_mem = 0;
1638 	sk_mem_reclaim(sk);
1639 }
1640 
1641 static inline void sk_mem_charge(struct sock *sk, int size)
1642 {
1643 	if (!sk_has_account(sk))
1644 		return;
1645 	sk_forward_alloc_add(sk, -size);
1646 }
1647 
1648 static inline void sk_mem_uncharge(struct sock *sk, int size)
1649 {
1650 	if (!sk_has_account(sk))
1651 		return;
1652 	sk_forward_alloc_add(sk, size);
1653 	sk_mem_reclaim(sk);
1654 }
1655 
1656 void __sk_charge(struct sock *sk, gfp_t gfp);
1657 
1658 #if IS_ENABLED(CONFIG_PROVE_LOCKING) && IS_ENABLED(CONFIG_MODULES)
1659 static inline void sk_owner_set(struct sock *sk, struct module *owner)
1660 {
1661 	__module_get(owner);
1662 	sk->sk_owner = owner;
1663 }
1664 
1665 static inline void sk_owner_clear(struct sock *sk)
1666 {
1667 	sk->sk_owner = NULL;
1668 }
1669 
1670 static inline void sk_owner_put(struct sock *sk)
1671 {
1672 	module_put(sk->sk_owner);
1673 }
1674 #else
1675 static inline void sk_owner_set(struct sock *sk, struct module *owner)
1676 {
1677 }
1678 
1679 static inline void sk_owner_clear(struct sock *sk)
1680 {
1681 }
1682 
1683 static inline void sk_owner_put(struct sock *sk)
1684 {
1685 }
1686 #endif
1687 /*
1688  * Macro so as to not evaluate some arguments when
1689  * lockdep is not enabled.
1690  *
1691  * Mark both the sk_lock and the sk_lock.slock as a
1692  * per-address-family lock class.
1693  */
1694 #define sock_lock_init_class_and_name(sk, sname, skey, name, key)	\
1695 do {									\
1696 	sk_owner_set(sk, THIS_MODULE);					\
1697 	sk->sk_lock.owned = 0;						\
1698 	init_waitqueue_head(&sk->sk_lock.wq);				\
1699 	spin_lock_init(&(sk)->sk_lock.slock);				\
1700 	debug_check_no_locks_freed((void *)&(sk)->sk_lock,		\
1701 				   sizeof((sk)->sk_lock));		\
1702 	lockdep_set_class_and_name(&(sk)->sk_lock.slock,		\
1703 				   (skey), (sname));			\
1704 	lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0);	\
1705 } while (0)
1706 
1707 static inline bool lockdep_sock_is_held(const struct sock *sk)
1708 {
1709 	return lockdep_is_held(&sk->sk_lock) ||
1710 	       lockdep_is_held(&sk->sk_lock.slock);
1711 }
1712 
1713 void lock_sock_nested(struct sock *sk, int subclass);
1714 
1715 static inline void lock_sock(struct sock *sk)
1716 {
1717 	lock_sock_nested(sk, 0);
1718 }
1719 
1720 void __release_sock(struct sock *sk);
1721 void release_sock(struct sock *sk);
1722 
1723 /* BH context may only use the following locking interface. */
1724 #define bh_lock_sock(__sk)	spin_lock(&((__sk)->sk_lock.slock))
1725 #define bh_lock_sock_nested(__sk) \
1726 				spin_lock_nested(&((__sk)->sk_lock.slock), \
1727 				SINGLE_DEPTH_NESTING)
1728 #define bh_unlock_sock(__sk)	spin_unlock(&((__sk)->sk_lock.slock))
1729 
1730 bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock);
1731 
1732 /**
1733  * lock_sock_fast - fast version of lock_sock
1734  * @sk: socket
1735  *
1736  * This version should be used for very small section, where process won't block
1737  * return false if fast path is taken:
1738  *
1739  *   sk_lock.slock locked, owned = 0, BH disabled
1740  *
1741  * return true if slow path is taken:
1742  *
1743  *   sk_lock.slock unlocked, owned = 1, BH enabled
1744  */
1745 static inline bool lock_sock_fast(struct sock *sk)
1746 {
1747 	/* The sk_lock has mutex_lock() semantics here. */
1748 	mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
1749 
1750 	return __lock_sock_fast(sk);
1751 }
1752 
1753 /* fast socket lock variant for caller already holding a [different] socket lock */
1754 static inline bool lock_sock_fast_nested(struct sock *sk)
1755 {
1756 	mutex_acquire(&sk->sk_lock.dep_map, SINGLE_DEPTH_NESTING, 0, _RET_IP_);
1757 
1758 	return __lock_sock_fast(sk);
1759 }
1760 
1761 /**
1762  * unlock_sock_fast - complement of lock_sock_fast
1763  * @sk: socket
1764  * @slow: slow mode
1765  *
1766  * fast unlock socket for user context.
1767  * If slow mode is on, we call regular release_sock()
1768  */
1769 static inline void unlock_sock_fast(struct sock *sk, bool slow)
1770 	__releases(&sk->sk_lock.slock)
1771 {
1772 	if (slow) {
1773 		release_sock(sk);
1774 		__release(&sk->sk_lock.slock);
1775 	} else {
1776 		mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
1777 		spin_unlock_bh(&sk->sk_lock.slock);
1778 	}
1779 }
1780 
1781 void sockopt_lock_sock(struct sock *sk);
1782 void sockopt_release_sock(struct sock *sk);
1783 bool sockopt_ns_capable(struct user_namespace *ns, int cap);
1784 bool sockopt_capable(int cap);
1785 
1786 /* Used by processes to "lock" a socket state, so that
1787  * interrupts and bottom half handlers won't change it
1788  * from under us. It essentially blocks any incoming
1789  * packets, so that we won't get any new data or any
1790  * packets that change the state of the socket.
1791  *
1792  * While locked, BH processing will add new packets to
1793  * the backlog queue.  This queue is processed by the
1794  * owner of the socket lock right before it is released.
1795  *
1796  * Since ~2.3.5 it is also exclusive sleep lock serializing
1797  * accesses from user process context.
1798  */
1799 
1800 static inline void sock_owned_by_me(const struct sock *sk)
1801 {
1802 #ifdef CONFIG_LOCKDEP
1803 	WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks);
1804 #endif
1805 }
1806 
1807 static inline void sock_not_owned_by_me(const struct sock *sk)
1808 {
1809 #ifdef CONFIG_LOCKDEP
1810 	WARN_ON_ONCE(lockdep_sock_is_held(sk) && debug_locks);
1811 #endif
1812 }
1813 
1814 static inline bool sock_owned_by_user(const struct sock *sk)
1815 {
1816 	sock_owned_by_me(sk);
1817 	return sk->sk_lock.owned;
1818 }
1819 
1820 static inline bool sock_owned_by_user_nocheck(const struct sock *sk)
1821 {
1822 	return sk->sk_lock.owned;
1823 }
1824 
1825 static inline void sock_release_ownership(struct sock *sk)
1826 {
1827 	DEBUG_NET_WARN_ON_ONCE(!sock_owned_by_user_nocheck(sk));
1828 	sk->sk_lock.owned = 0;
1829 
1830 	/* The sk_lock has mutex_unlock() semantics: */
1831 	mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
1832 }
1833 
1834 /* no reclassification while locks are held */
1835 static inline bool sock_allow_reclassification(const struct sock *csk)
1836 {
1837 	struct sock *sk = (struct sock *)csk;
1838 
1839 	return !sock_owned_by_user_nocheck(sk) &&
1840 		!spin_is_locked(&sk->sk_lock.slock);
1841 }
1842 
1843 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1844 		      struct proto *prot, int kern);
1845 void sk_free(struct sock *sk);
1846 void sk_net_refcnt_upgrade(struct sock *sk);
1847 void sk_destruct(struct sock *sk);
1848 struct sock *sk_clone(const struct sock *sk, const gfp_t priority, bool lock);
1849 
1850 static inline struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
1851 {
1852 	return sk_clone(sk, priority, true);
1853 }
1854 
1855 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1856 			     gfp_t priority);
1857 void sock_wfree(struct sk_buff *skb);
1858 void __sock_wfree(struct sk_buff *skb);
1859 void tcp_wfree(struct sk_buff *skb);
1860 
1861 static inline bool is_skb_wmem(const struct sk_buff *skb)
1862 {
1863 	return skb->destructor == sock_wfree ||
1864 	       (IS_ENABLED(CONFIG_INET) && skb->destructor == __sock_wfree) ||
1865 	       (IS_ENABLED(CONFIG_INET) && skb->destructor == tcp_wfree);
1866 }
1867 
1868 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
1869 			     gfp_t priority);
1870 void skb_orphan_partial(struct sk_buff *skb);
1871 void sock_rfree(struct sk_buff *skb);
1872 void sock_rmem_free(struct sk_buff *skb);
1873 void sock_efree(struct sk_buff *skb);
1874 #ifdef CONFIG_INET
1875 void sock_edemux(struct sk_buff *skb);
1876 void sock_pfree(struct sk_buff *skb);
1877 
1878 static inline void skb_set_owner_edemux(struct sk_buff *skb, struct sock *sk)
1879 {
1880 	skb_orphan(skb);
1881 	if (refcount_inc_not_zero(&sk->sk_refcnt)) {
1882 		skb->sk = sk;
1883 		skb->destructor = sock_edemux;
1884 	}
1885 }
1886 #else
1887 #define sock_edemux sock_efree
1888 #endif
1889 
1890 int sk_setsockopt(struct sock *sk, int level, int optname,
1891 		  sockptr_t optval, unsigned int optlen);
1892 int sock_setsockopt(struct socket *sock, int level, int op,
1893 		    sockptr_t optval, unsigned int optlen);
1894 int do_sock_setsockopt(struct socket *sock, bool compat, int level,
1895 		       int optname, sockptr_t optval, int optlen);
1896 int do_sock_getsockopt(struct socket *sock, bool compat, int level,
1897 		       int optname, sockptr_t optval, sockptr_t optlen);
1898 
1899 int sk_getsockopt(struct sock *sk, int level, int optname,
1900 		  sockptr_t optval, sockptr_t optlen);
1901 int sock_gettstamp(struct socket *sock, void __user *userstamp,
1902 		   bool timeval, bool time32);
1903 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1904 				     unsigned long data_len, int noblock,
1905 				     int *errcode, int max_page_order);
1906 
1907 static inline struct sk_buff *sock_alloc_send_skb(struct sock *sk,
1908 						  unsigned long size,
1909 						  int noblock, int *errcode)
1910 {
1911 	return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0);
1912 }
1913 
1914 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority);
1915 void *sock_kmemdup(struct sock *sk, const void *src,
1916 		   int size, gfp_t priority);
1917 void sock_kfree_s(struct sock *sk, void *mem, int size);
1918 void sock_kzfree_s(struct sock *sk, void *mem, int size);
1919 void sk_send_sigurg(struct sock *sk);
1920 
1921 static inline void sock_replace_proto(struct sock *sk, struct proto *proto)
1922 {
1923 	if (sk->sk_socket)
1924 		clear_bit(SOCK_SUPPORT_ZC, &sk->sk_socket->flags);
1925 	WRITE_ONCE(sk->sk_prot, proto);
1926 }
1927 
1928 struct sockcm_cookie {
1929 	u64 transmit_time;
1930 	u32 mark;
1931 	u32 tsflags;
1932 	u32 ts_opt_id;
1933 	u32 priority;
1934 	u32 dmabuf_id;
1935 };
1936 
1937 static inline void sockcm_init(struct sockcm_cookie *sockc,
1938 			       const struct sock *sk)
1939 {
1940 	*sockc = (struct sockcm_cookie) {
1941 		.mark = READ_ONCE(sk->sk_mark),
1942 		.tsflags = READ_ONCE(sk->sk_tsflags),
1943 		.priority = READ_ONCE(sk->sk_priority),
1944 	};
1945 }
1946 
1947 int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg,
1948 		     struct sockcm_cookie *sockc);
1949 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
1950 		   struct sockcm_cookie *sockc);
1951 
1952 /*
1953  * Functions to fill in entries in struct proto_ops when a protocol
1954  * does not implement a particular function.
1955  */
1956 int sock_no_bind(struct socket *sock, struct sockaddr_unsized *saddr, int len);
1957 int sock_no_connect(struct socket *sock, struct sockaddr_unsized *saddr, int len, int flags);
1958 int sock_no_socketpair(struct socket *, struct socket *);
1959 int sock_no_accept(struct socket *, struct socket *, struct proto_accept_arg *);
1960 int sock_no_getname(struct socket *, struct sockaddr *, int);
1961 int sock_no_ioctl(struct socket *, unsigned int, unsigned long);
1962 int sock_no_listen(struct socket *, int);
1963 int sock_no_shutdown(struct socket *, int);
1964 int sock_no_sendmsg(struct socket *, struct msghdr *, size_t);
1965 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len);
1966 int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int);
1967 int sock_no_mmap(struct file *file, struct socket *sock,
1968 		 struct vm_area_struct *vma);
1969 
1970 /*
1971  * Functions to fill in entries in struct proto_ops when a protocol
1972  * uses the inet style.
1973  */
1974 int sock_common_getsockopt(struct socket *sock, int level, int optname,
1975 				  char __user *optval, int __user *optlen);
1976 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1977 			int flags);
1978 int sock_common_setsockopt(struct socket *sock, int level, int optname,
1979 			   sockptr_t optval, unsigned int optlen);
1980 
1981 void sk_common_release(struct sock *sk);
1982 
1983 /*
1984  *	Default socket callbacks and setup code
1985  */
1986 
1987 /* Initialise core socket variables using an explicit uid. */
1988 void sock_init_data_uid(struct socket *sock, struct sock *sk, kuid_t uid);
1989 
1990 /* Initialise core socket variables.
1991  * Assumes struct socket *sock is embedded in a struct socket_alloc.
1992  */
1993 void sock_init_data(struct socket *sock, struct sock *sk);
1994 
1995 /*
1996  * Socket reference counting postulates.
1997  *
1998  * * Each user of socket SHOULD hold a reference count.
1999  * * Each access point to socket (an hash table bucket, reference from a list,
2000  *   running timer, skb in flight MUST hold a reference count.
2001  * * When reference count hits 0, it means it will never increase back.
2002  * * When reference count hits 0, it means that no references from
2003  *   outside exist to this socket and current process on current CPU
2004  *   is last user and may/should destroy this socket.
2005  * * sk_free is called from any context: process, BH, IRQ. When
2006  *   it is called, socket has no references from outside -> sk_free
2007  *   may release descendant resources allocated by the socket, but
2008  *   to the time when it is called, socket is NOT referenced by any
2009  *   hash tables, lists etc.
2010  * * Packets, delivered from outside (from network or from another process)
2011  *   and enqueued on receive/error queues SHOULD NOT grab reference count,
2012  *   when they sit in queue. Otherwise, packets will leak to hole, when
2013  *   socket is looked up by one cpu and unhasing is made by another CPU.
2014  *   It is true for udp/raw, netlink (leak to receive and error queues), tcp
2015  *   (leak to backlog). Packet socket does all the processing inside
2016  *   BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
2017  *   use separate SMP lock, so that they are prone too.
2018  */
2019 
2020 /* Ungrab socket and destroy it, if it was the last reference. */
2021 static inline void sock_put(struct sock *sk)
2022 {
2023 	if (refcount_dec_and_test(&sk->sk_refcnt))
2024 		sk_free(sk);
2025 }
2026 /* Generic version of sock_put(), dealing with all sockets
2027  * (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...)
2028  */
2029 void sock_gen_put(struct sock *sk);
2030 
2031 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested,
2032 		     unsigned int trim_cap, bool refcounted);
2033 static inline int sk_receive_skb(struct sock *sk, struct sk_buff *skb,
2034 				 const int nested)
2035 {
2036 	return __sk_receive_skb(sk, skb, nested, 1, true);
2037 }
2038 
2039 static inline void sk_tx_queue_set(struct sock *sk, int tx_queue)
2040 {
2041 	/* sk_tx_queue_mapping accept only upto a 16-bit value */
2042 	if (WARN_ON_ONCE((unsigned short)tx_queue >= USHRT_MAX))
2043 		return;
2044 	/* Paired with READ_ONCE() in sk_tx_queue_get() and
2045 	 * other WRITE_ONCE() because socket lock might be not held.
2046 	 */
2047 	if (READ_ONCE(sk->sk_tx_queue_mapping) != tx_queue) {
2048 		WRITE_ONCE(sk->sk_tx_queue_mapping, tx_queue);
2049 		WRITE_ONCE(sk->sk_tx_queue_mapping_jiffies, jiffies);
2050 		return;
2051 	}
2052 
2053 	/* Refresh sk_tx_queue_mapping_jiffies if too old. */
2054 	if (time_is_before_jiffies(READ_ONCE(sk->sk_tx_queue_mapping_jiffies) + HZ))
2055 		WRITE_ONCE(sk->sk_tx_queue_mapping_jiffies, jiffies);
2056 }
2057 
2058 #define NO_QUEUE_MAPPING	USHRT_MAX
2059 
2060 static inline void sk_tx_queue_clear(struct sock *sk)
2061 {
2062 	/* Paired with READ_ONCE() in sk_tx_queue_get() and
2063 	 * other WRITE_ONCE() because socket lock might be not held.
2064 	 */
2065 	WRITE_ONCE(sk->sk_tx_queue_mapping, NO_QUEUE_MAPPING);
2066 }
2067 
2068 int sk_tx_queue_get(const struct sock *sk);
2069 
2070 static inline void __sk_rx_queue_set(struct sock *sk,
2071 				     const struct sk_buff *skb,
2072 				     bool force_set)
2073 {
2074 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
2075 	if (skb_rx_queue_recorded(skb)) {
2076 		u16 rx_queue = skb_get_rx_queue(skb);
2077 
2078 		if (force_set ||
2079 		    unlikely(READ_ONCE(sk->sk_rx_queue_mapping) != rx_queue))
2080 			WRITE_ONCE(sk->sk_rx_queue_mapping, rx_queue);
2081 	}
2082 #endif
2083 }
2084 
2085 static inline void sk_rx_queue_set(struct sock *sk, const struct sk_buff *skb)
2086 {
2087 	__sk_rx_queue_set(sk, skb, true);
2088 }
2089 
2090 static inline void sk_rx_queue_update(struct sock *sk, const struct sk_buff *skb)
2091 {
2092 	__sk_rx_queue_set(sk, skb, false);
2093 }
2094 
2095 static inline void sk_rx_queue_clear(struct sock *sk)
2096 {
2097 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
2098 	WRITE_ONCE(sk->sk_rx_queue_mapping, NO_QUEUE_MAPPING);
2099 #endif
2100 }
2101 
2102 static inline int sk_rx_queue_get(const struct sock *sk)
2103 {
2104 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
2105 	if (sk) {
2106 		int res = READ_ONCE(sk->sk_rx_queue_mapping);
2107 
2108 		if (res != NO_QUEUE_MAPPING)
2109 			return res;
2110 	}
2111 #endif
2112 
2113 	return -1;
2114 }
2115 
2116 static inline void sk_set_socket(struct sock *sk, struct socket *sock)
2117 {
2118 	WRITE_ONCE(sk->sk_socket, sock);
2119 	if (sock) {
2120 		WRITE_ONCE(sk->sk_uid, SOCK_INODE(sock)->i_uid);
2121 		WRITE_ONCE(sk->sk_ino, SOCK_INODE(sock)->i_ino);
2122 	} else {
2123 		/* Note: sk_uid is unchanged. */
2124 		WRITE_ONCE(sk->sk_ino, 0);
2125 	}
2126 }
2127 
2128 static inline wait_queue_head_t *sk_sleep(struct sock *sk)
2129 {
2130 	BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0);
2131 	return &rcu_dereference_raw(sk->sk_wq)->wait;
2132 }
2133 /* Detach socket from process context.
2134  * Announce socket dead, detach it from wait queue and inode.
2135  * Note that parent inode held reference count on this struct sock,
2136  * we do not release it in this function, because protocol
2137  * probably wants some additional cleanups or even continuing
2138  * to work with this socket (TCP).
2139  */
2140 static inline void sock_orphan(struct sock *sk)
2141 {
2142 	write_lock_bh(&sk->sk_callback_lock);
2143 	sock_set_flag(sk, SOCK_DEAD);
2144 	sk_set_socket(sk, NULL);
2145 	sk->sk_wq  = NULL;
2146 	write_unlock_bh(&sk->sk_callback_lock);
2147 }
2148 
2149 static inline void sock_graft(struct sock *sk, struct socket *parent)
2150 {
2151 	WARN_ON(parent->sk);
2152 	write_lock_bh(&sk->sk_callback_lock);
2153 	rcu_assign_pointer(sk->sk_wq, &parent->wq);
2154 	parent->sk = sk;
2155 	sk_set_socket(sk, parent);
2156 	security_sock_graft(sk, parent);
2157 	write_unlock_bh(&sk->sk_callback_lock);
2158 }
2159 
2160 static inline u64 sock_i_ino(const struct sock *sk)
2161 {
2162 	/* Paired with WRITE_ONCE() in sock_graft() and sock_orphan() */
2163 	return READ_ONCE(sk->sk_ino);
2164 }
2165 
2166 static inline kuid_t sk_uid(const struct sock *sk)
2167 {
2168 	/* Paired with WRITE_ONCE() in sockfs_setattr() */
2169 	return READ_ONCE(sk->sk_uid);
2170 }
2171 
2172 static inline kuid_t sock_net_uid(const struct net *net, const struct sock *sk)
2173 {
2174 	return sk ? sk_uid(sk) : make_kuid(net->user_ns, 0);
2175 }
2176 
2177 static inline u32 net_tx_rndhash(void)
2178 {
2179 	u32 v = get_random_u32();
2180 
2181 	return v ?: 1;
2182 }
2183 
2184 static inline void sk_set_txhash(struct sock *sk)
2185 {
2186 	/* This pairs with READ_ONCE() in skb_set_hash_from_sk() */
2187 	WRITE_ONCE(sk->sk_txhash, net_tx_rndhash());
2188 }
2189 
2190 static inline bool sk_rethink_txhash(struct sock *sk)
2191 {
2192 	if (sk->sk_txhash && sk->sk_txrehash == SOCK_TXREHASH_ENABLED) {
2193 		sk_set_txhash(sk);
2194 		return true;
2195 	}
2196 	return false;
2197 }
2198 
2199 static inline struct dst_entry *
2200 __sk_dst_get(const struct sock *sk)
2201 {
2202 	return rcu_dereference_check(sk->sk_dst_cache,
2203 				     lockdep_sock_is_held(sk));
2204 }
2205 
2206 static inline struct dst_entry *
2207 sk_dst_get(const struct sock *sk)
2208 {
2209 	struct dst_entry *dst;
2210 
2211 	rcu_read_lock();
2212 	dst = rcu_dereference(sk->sk_dst_cache);
2213 	if (dst && !rcuref_get(&dst->__rcuref))
2214 		dst = NULL;
2215 	rcu_read_unlock();
2216 	return dst;
2217 }
2218 
2219 static inline void __dst_negative_advice(struct sock *sk)
2220 {
2221 	struct dst_entry *dst = __sk_dst_get(sk);
2222 
2223 	if (dst && dst->ops->negative_advice)
2224 		dst->ops->negative_advice(sk, dst);
2225 }
2226 
2227 static inline void dst_negative_advice(struct sock *sk)
2228 {
2229 	sk_rethink_txhash(sk);
2230 	__dst_negative_advice(sk);
2231 }
2232 
2233 static inline void
2234 __sk_dst_set(struct sock *sk, struct dst_entry *dst)
2235 {
2236 	struct dst_entry *old_dst;
2237 
2238 	sk_tx_queue_clear(sk);
2239 	WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2240 	old_dst = rcu_dereference_protected(sk->sk_dst_cache,
2241 					    lockdep_sock_is_held(sk));
2242 	rcu_assign_pointer(sk->sk_dst_cache, dst);
2243 	dst_release(old_dst);
2244 }
2245 
2246 static inline void
2247 sk_dst_set(struct sock *sk, struct dst_entry *dst)
2248 {
2249 	struct dst_entry *old_dst;
2250 
2251 	sk_tx_queue_clear(sk);
2252 	WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2253 	old_dst = unrcu_pointer(xchg(&sk->sk_dst_cache, RCU_INITIALIZER(dst)));
2254 	dst_release(old_dst);
2255 }
2256 
2257 static inline void
2258 __sk_dst_reset(struct sock *sk)
2259 {
2260 	__sk_dst_set(sk, NULL);
2261 }
2262 
2263 static inline void
2264 sk_dst_reset(struct sock *sk)
2265 {
2266 	sk_dst_set(sk, NULL);
2267 }
2268 
2269 /* Re-roll the socket txhash.  On a rehash, IPv6 also drops the cached route
2270  * so the next transmit re-selects an ECMP path; IPv4 keeps its route, since
2271  * IPv4 ECMP path selection does not use sk_txhash.
2272  */
2273 static inline bool __sk_rethink_txhash_reset_dst(struct sock *sk)
2274 {
2275 	if (sk_rethink_txhash(sk)) {
2276 		if (sk->sk_family == AF_INET6)
2277 			__sk_dst_reset(sk);
2278 		return true;
2279 	}
2280 	return false;
2281 }
2282 
2283 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
2284 
2285 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
2286 
2287 static inline void sk_dst_confirm(struct sock *sk)
2288 {
2289 	if (!READ_ONCE(sk->sk_dst_pending_confirm))
2290 		WRITE_ONCE(sk->sk_dst_pending_confirm, 1);
2291 }
2292 
2293 static inline void sock_confirm_neigh(struct sk_buff *skb, struct neighbour *n)
2294 {
2295 	if (skb_get_dst_pending_confirm(skb)) {
2296 		struct sock *sk = skb->sk;
2297 
2298 		if (sk && READ_ONCE(sk->sk_dst_pending_confirm))
2299 			WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2300 		neigh_confirm(n);
2301 	}
2302 }
2303 
2304 bool sk_mc_loop(const struct sock *sk);
2305 
2306 static inline bool sk_can_gso(const struct sock *sk)
2307 {
2308 	return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type);
2309 }
2310 
2311 void sk_setup_caps(struct sock *sk, struct dst_entry *dst);
2312 
2313 static inline void sk_gso_disable(struct sock *sk)
2314 {
2315 	sk->sk_gso_disabled = 1;
2316 	sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2317 }
2318 
2319 bool sk_has_decrypt_user(const struct sock *sk);
2320 
2321 static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
2322 					   struct iov_iter *from, char *to,
2323 					   int copy, int offset)
2324 {
2325 	if (skb->ip_summed == CHECKSUM_NONE) {
2326 		__wsum csum = 0;
2327 		if (!csum_and_copy_from_iter_full(to, copy, &csum, from))
2328 			return -EFAULT;
2329 		skb->csum = csum_block_add(skb->csum, csum, offset);
2330 	} else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
2331 		if (!copy_from_iter_full_nocache(to, copy, from))
2332 			return -EFAULT;
2333 	} else if (!copy_from_iter_full(to, copy, from))
2334 		return -EFAULT;
2335 
2336 	return 0;
2337 }
2338 
2339 static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
2340 				       struct iov_iter *from, int copy)
2341 {
2342 	int err, offset = skb->len;
2343 
2344 	err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy),
2345 				       copy, offset);
2346 	if (err)
2347 		__skb_trim(skb, offset);
2348 
2349 	return err;
2350 }
2351 
2352 static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from,
2353 					   struct sk_buff *skb,
2354 					   struct page *page,
2355 					   int off, int copy)
2356 {
2357 	int err;
2358 
2359 	err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off,
2360 				       copy, skb->len);
2361 	if (err)
2362 		return err;
2363 
2364 	skb_len_add(skb, copy);
2365 	sk_wmem_queued_add(sk, copy);
2366 	sk_mem_charge(sk, copy);
2367 	return 0;
2368 }
2369 
2370 #define SK_WMEM_ALLOC_BIAS 1
2371 /**
2372  * sk_wmem_alloc_get - returns write allocations
2373  * @sk: socket
2374  *
2375  * Return: sk_wmem_alloc minus initial offset of one
2376  */
2377 static inline int sk_wmem_alloc_get(const struct sock *sk)
2378 {
2379 	return refcount_read(&sk->sk_wmem_alloc) - SK_WMEM_ALLOC_BIAS;
2380 }
2381 
2382 /**
2383  * sk_rmem_alloc_get - returns read allocations
2384  * @sk: socket
2385  *
2386  * Return: sk_rmem_alloc
2387  */
2388 static inline int sk_rmem_alloc_get(const struct sock *sk)
2389 {
2390 	return atomic_read(&sk->sk_rmem_alloc);
2391 }
2392 
2393 /**
2394  * sk_has_allocations - check if allocations are outstanding
2395  * @sk: socket
2396  *
2397  * Return: true if socket has write or read allocations
2398  */
2399 static inline bool sk_has_allocations(const struct sock *sk)
2400 {
2401 	return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk);
2402 }
2403 
2404 /**
2405  * skwq_has_sleeper - check if there are any waiting processes
2406  * @wq: struct socket_wq
2407  *
2408  * Return: true if socket_wq has waiting processes
2409  *
2410  * The purpose of the skwq_has_sleeper and sock_poll_wait is to wrap the memory
2411  * barrier call. They were added due to the race found within the tcp code.
2412  *
2413  * Consider following tcp code paths::
2414  *
2415  *   CPU1                CPU2
2416  *   sys_select          receive packet
2417  *   ...                 ...
2418  *   __add_wait_queue    update tp->rcv_nxt
2419  *   ...                 ...
2420  *   tp->rcv_nxt check   sock_def_readable
2421  *   ...                 {
2422  *   schedule               rcu_read_lock();
2423  *                          wq = rcu_dereference(sk->sk_wq);
2424  *                          if (wq && waitqueue_active(&wq->wait))
2425  *                              wake_up_interruptible(&wq->wait)
2426  *                          ...
2427  *                       }
2428  *
2429  * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
2430  * in its cache, and so does the tp->rcv_nxt update on CPU2 side.  The CPU1
2431  * could then endup calling schedule and sleep forever if there are no more
2432  * data on the socket.
2433  *
2434  */
2435 static inline bool skwq_has_sleeper(struct socket_wq *wq)
2436 {
2437 	return wq && wq_has_sleeper(&wq->wait);
2438 }
2439 
2440 /**
2441  * sock_poll_wait - wrapper for the poll_wait call.
2442  * @filp:           file
2443  * @sock:           socket to wait on
2444  * @p:              poll_table
2445  *
2446  * See the comments in the wq_has_sleeper function.
2447  */
2448 static inline void sock_poll_wait(struct file *filp, struct socket *sock,
2449 				  poll_table *p)
2450 {
2451 	/* Provides a barrier we need to be sure we are in sync
2452 	 * with the socket flags modification.
2453 	 *
2454 	 * This memory barrier is paired in the wq_has_sleeper.
2455 	 */
2456 	poll_wait(filp, &sock->wq.wait, p);
2457 }
2458 
2459 static inline void skb_set_hash_from_sk(struct sk_buff *skb, struct sock *sk)
2460 {
2461 	/* This pairs with WRITE_ONCE() in sk_set_txhash() */
2462 	u32 txhash = READ_ONCE(sk->sk_txhash);
2463 
2464 	if (txhash) {
2465 		skb->l4_hash = 1;
2466 		skb->hash = txhash;
2467 	}
2468 }
2469 
2470 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk);
2471 
2472 /*
2473  *	Queue a received datagram if it will fit. Stream and sequenced
2474  *	protocols can't normally use this as they need to fit buffers in
2475  *	and play with them.
2476  *
2477  *	Inlined as it's very short and called for pretty much every
2478  *	packet ever received.
2479  */
2480 static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
2481 {
2482 	skb_orphan(skb);
2483 	skb->sk = sk;
2484 	skb->destructor = sock_rfree;
2485 	atomic_add(skb->truesize, &sk->sk_rmem_alloc);
2486 	sk_mem_charge(sk, skb->truesize);
2487 }
2488 
2489 static inline __must_check bool skb_set_owner_sk_safe(struct sk_buff *skb, struct sock *sk)
2490 {
2491 	if (sk && refcount_inc_not_zero(&sk->sk_refcnt)) {
2492 		skb_orphan(skb);
2493 		skb->destructor = sock_efree;
2494 		skb->sk = sk;
2495 		return true;
2496 	}
2497 	return false;
2498 }
2499 
2500 static inline struct sk_buff *skb_clone_and_charge_r(struct sk_buff *skb, struct sock *sk)
2501 {
2502 	skb = skb_clone(skb, sk_gfp_mask(sk, GFP_ATOMIC));
2503 	if (skb) {
2504 		if (sk_rmem_schedule(sk, skb, skb->truesize)) {
2505 			skb_set_owner_r(skb, sk);
2506 			return skb;
2507 		}
2508 		__kfree_skb(skb);
2509 	}
2510 	return NULL;
2511 }
2512 
2513 static inline void skb_prepare_for_gro(struct sk_buff *skb)
2514 {
2515 	if (skb->destructor != sock_wfree) {
2516 		skb_orphan(skb);
2517 		return;
2518 	}
2519 	skb->slow_gro = 1;
2520 }
2521 
2522 void sk_reset_timer(struct sock *sk, struct timer_list *timer,
2523 		    unsigned long expires);
2524 
2525 void sk_stop_timer(struct sock *sk, struct timer_list *timer);
2526 
2527 void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer);
2528 
2529 int __sk_queue_drop_skb(struct sock *sk, struct sk_buff_head *sk_queue,
2530 			struct sk_buff *skb, unsigned int flags,
2531 			void (*destructor)(struct sock *sk,
2532 					   struct sk_buff *skb));
2533 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
2534 
2535 enum skb_drop_reason
2536 sock_queue_rcv_skb_reason(struct sock *sk, struct sk_buff *skb);
2537 
2538 static inline int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
2539 {
2540 	enum skb_drop_reason drop_reason = sock_queue_rcv_skb_reason(sk, skb);
2541 
2542 	switch (drop_reason) {
2543 	case SKB_DROP_REASON_SOCKET_RCVBUFF:
2544 		return -ENOMEM;
2545 	case SKB_DROP_REASON_PROTO_MEM:
2546 		return -ENOBUFS;
2547 	case 0:
2548 		return 0;
2549 	default:
2550 		return -EPERM;
2551 	}
2552 }
2553 
2554 int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
2555 struct sk_buff *sock_dequeue_err_skb(struct sock *sk);
2556 
2557 /*
2558  *	Recover an error report and clear atomically
2559  */
2560 
2561 static inline int sock_error(struct sock *sk)
2562 {
2563 	int err;
2564 
2565 	/* Avoid an atomic operation for the common case.
2566 	 * This is racy since another cpu/thread can change sk_err under us.
2567 	 */
2568 	if (likely(data_race(!sk->sk_err)))
2569 		return 0;
2570 
2571 	err = xchg(&sk->sk_err, 0);
2572 	return -err;
2573 }
2574 
2575 void sk_error_report(struct sock *sk);
2576 
2577 static inline unsigned long sock_wspace(struct sock *sk)
2578 {
2579 	int amt = 0;
2580 
2581 	if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
2582 		amt = sk->sk_sndbuf - refcount_read(&sk->sk_wmem_alloc);
2583 		if (amt < 0)
2584 			amt = 0;
2585 	}
2586 	return amt;
2587 }
2588 
2589 /* Note:
2590  *  We use sk->sk_wq_raw, from contexts knowing this
2591  *  pointer is not NULL and cannot disappear/change.
2592  */
2593 static inline void sk_set_bit(int nr, struct sock *sk)
2594 {
2595 	if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2596 	    !sock_flag(sk, SOCK_FASYNC))
2597 		return;
2598 
2599 	set_bit(nr, &sk->sk_wq_raw->flags);
2600 }
2601 
2602 static inline void sk_clear_bit(int nr, struct sock *sk)
2603 {
2604 	if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2605 	    !sock_flag(sk, SOCK_FASYNC))
2606 		return;
2607 
2608 	clear_bit(nr, &sk->sk_wq_raw->flags);
2609 }
2610 
2611 static inline void sk_wake_async(const struct sock *sk, int how, int band)
2612 {
2613 	if (sock_flag(sk, SOCK_FASYNC)) {
2614 		rcu_read_lock();
2615 		sock_wake_async(rcu_dereference(sk->sk_wq), how, band);
2616 		rcu_read_unlock();
2617 	}
2618 }
2619 
2620 static inline void sk_wake_async_rcu(const struct sock *sk, int how, int band)
2621 {
2622 	if (unlikely(sock_flag(sk, SOCK_FASYNC)))
2623 		sock_wake_async(rcu_dereference(sk->sk_wq), how, band);
2624 }
2625 
2626 /* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might
2627  * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak.
2628  * Note: for send buffers, TCP works better if we can build two skbs at
2629  * minimum.
2630  */
2631 #define TCP_SKB_MIN_TRUESIZE	(2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff)))
2632 
2633 #define SOCK_MIN_SNDBUF		(TCP_SKB_MIN_TRUESIZE * 2)
2634 #define SOCK_MIN_RCVBUF		 TCP_SKB_MIN_TRUESIZE
2635 
2636 static inline void sk_stream_moderate_sndbuf(struct sock *sk)
2637 {
2638 	u32 val;
2639 
2640 	if (sk->sk_userlocks & SOCK_SNDBUF_LOCK)
2641 		return;
2642 
2643 	val = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
2644 	val = max_t(u32, val, sk_unused_reserved_mem(sk));
2645 
2646 	WRITE_ONCE(sk->sk_sndbuf, max_t(u32, val, SOCK_MIN_SNDBUF));
2647 }
2648 
2649 /**
2650  * sk_page_frag - return an appropriate page_frag
2651  * @sk: socket
2652  *
2653  * Use the per task page_frag instead of the per socket one for
2654  * optimization when we know that we're in process context and own
2655  * everything that's associated with %current.
2656  *
2657  * Both direct reclaim and page faults can nest inside other
2658  * socket operations and end up recursing into sk_page_frag()
2659  * while it's already in use: explicitly avoid task page_frag
2660  * when users disable sk_use_task_frag.
2661  *
2662  * Return: a per task page_frag if context allows that,
2663  * otherwise a per socket one.
2664  */
2665 static inline struct page_frag *sk_page_frag(struct sock *sk)
2666 {
2667 	if (sk->sk_use_task_frag)
2668 		return &current->task_frag;
2669 
2670 	return &sk->sk_frag;
2671 }
2672 
2673 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag);
2674 
2675 static inline bool __sock_writeable(const struct sock *sk, int wmem_alloc)
2676 {
2677 	return wmem_alloc < (READ_ONCE(sk->sk_sndbuf) >> 1);
2678 }
2679 /*
2680  *	Default write policy as shown to user space via poll/select/SIGIO
2681  */
2682 static inline bool sock_writeable(const struct sock *sk)
2683 {
2684 	return __sock_writeable(sk, refcount_read(&sk->sk_wmem_alloc));
2685 }
2686 
2687 static inline gfp_t gfp_any(void)
2688 {
2689 	return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2690 }
2691 
2692 static inline gfp_t gfp_memcg_charge(void)
2693 {
2694 	return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2695 }
2696 
2697 #ifdef CONFIG_MEMCG
2698 static inline struct mem_cgroup *mem_cgroup_from_sk(const struct sock *sk)
2699 {
2700 	return sk->sk_memcg;
2701 }
2702 
2703 static inline bool mem_cgroup_sk_enabled(const struct sock *sk)
2704 {
2705 	return mem_cgroup_sockets_enabled && mem_cgroup_from_sk(sk);
2706 }
2707 
2708 static inline bool mem_cgroup_sk_under_memory_pressure(const struct sock *sk)
2709 {
2710 	struct mem_cgroup *memcg = mem_cgroup_from_sk(sk);
2711 
2712 #ifdef CONFIG_MEMCG_V1
2713 	if (!cgroup_subsys_on_dfl(memory_cgrp_subsys))
2714 		return !!memcg->tcpmem_pressure;
2715 #endif /* CONFIG_MEMCG_V1 */
2716 
2717 	do {
2718 		if (time_before64(get_jiffies_64(),
2719 				  mem_cgroup_get_socket_pressure(memcg))) {
2720 			memcg_memory_event(mem_cgroup_from_sk(sk),
2721 					   MEMCG_SOCK_THROTTLED);
2722 			return true;
2723 		}
2724 	} while ((memcg = parent_mem_cgroup(memcg)));
2725 
2726 	return false;
2727 }
2728 #else
2729 static inline struct mem_cgroup *mem_cgroup_from_sk(const struct sock *sk)
2730 {
2731 	return NULL;
2732 }
2733 
2734 static inline bool mem_cgroup_sk_enabled(const struct sock *sk)
2735 {
2736 	return false;
2737 }
2738 
2739 static inline bool mem_cgroup_sk_under_memory_pressure(const struct sock *sk)
2740 {
2741 	return false;
2742 }
2743 #endif
2744 
2745 static inline long sock_rcvtimeo(const struct sock *sk, bool noblock)
2746 {
2747 	return noblock ? 0 : READ_ONCE(sk->sk_rcvtimeo);
2748 }
2749 
2750 static inline long sock_sndtimeo(const struct sock *sk, bool noblock)
2751 {
2752 	return noblock ? 0 : READ_ONCE(sk->sk_sndtimeo);
2753 }
2754 
2755 static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
2756 {
2757 	int v = waitall ? len : min_t(int, READ_ONCE(sk->sk_rcvlowat), len);
2758 
2759 	return v ?: 1;
2760 }
2761 
2762 /* Alas, with timeout socket operations are not restartable.
2763  * Compare this to poll().
2764  */
2765 static inline int sock_intr_errno(long timeo)
2766 {
2767 	return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
2768 }
2769 
2770 struct sock_skb_cb {
2771 	u32 dropcount;
2772 };
2773 
2774 /* Store sock_skb_cb at the end of skb->cb[] so protocol families
2775  * using skb->cb[] would keep using it directly and utilize its
2776  * alignment guarantee.
2777  */
2778 #define SOCK_SKB_CB_OFFSET (sizeof_field(struct sk_buff, cb) - \
2779 			    sizeof(struct sock_skb_cb))
2780 
2781 #define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \
2782 			    SOCK_SKB_CB_OFFSET))
2783 
2784 #define sock_skb_cb_check_size(size) \
2785 	BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET)
2786 
2787 static inline void sk_drops_add(struct sock *sk, int segs)
2788 {
2789 	struct numa_drop_counters *ndc = sk->sk_drop_counters;
2790 
2791 	if (ndc)
2792 		numa_drop_add(ndc, segs);
2793 	else
2794 		atomic_add(segs, &sk->sk_drops);
2795 }
2796 
2797 static inline void sk_drops_inc(struct sock *sk)
2798 {
2799 	sk_drops_add(sk, 1);
2800 }
2801 
2802 static inline int sk_drops_read(const struct sock *sk)
2803 {
2804 	const struct numa_drop_counters *ndc = sk->sk_drop_counters;
2805 
2806 	if (ndc) {
2807 		DEBUG_NET_WARN_ON_ONCE(atomic_read(&sk->sk_drops));
2808 		return numa_drop_read(ndc);
2809 	}
2810 	return atomic_read(&sk->sk_drops);
2811 }
2812 
2813 static inline void sk_drops_reset(struct sock *sk)
2814 {
2815 	struct numa_drop_counters *ndc = sk->sk_drop_counters;
2816 
2817 	if (ndc)
2818 		numa_drop_reset(ndc);
2819 	atomic_set(&sk->sk_drops, 0);
2820 }
2821 
2822 static inline void
2823 sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb)
2824 {
2825 	SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, SOCK_RXQ_OVFL) ?
2826 						sk_drops_read(sk) : 0;
2827 }
2828 
2829 static inline void sk_drops_skbadd(struct sock *sk, const struct sk_buff *skb)
2830 {
2831 	int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs);
2832 
2833 	sk_drops_add(sk, segs);
2834 }
2835 
2836 static inline ktime_t sock_read_timestamp(struct sock *sk)
2837 {
2838 #if BITS_PER_LONG==32
2839 	unsigned int seq;
2840 	ktime_t kt;
2841 
2842 	do {
2843 		seq = read_seqbegin(&sk->sk_stamp_seq);
2844 		kt = sk->sk_stamp;
2845 	} while (read_seqretry(&sk->sk_stamp_seq, seq));
2846 
2847 	return kt;
2848 #else
2849 	return READ_ONCE(sk->sk_stamp);
2850 #endif
2851 }
2852 
2853 static inline void sock_write_timestamp(struct sock *sk, ktime_t kt)
2854 {
2855 #if BITS_PER_LONG==32
2856 	write_seqlock(&sk->sk_stamp_seq);
2857 	sk->sk_stamp = kt;
2858 	write_sequnlock(&sk->sk_stamp_seq);
2859 #else
2860 	WRITE_ONCE(sk->sk_stamp, kt);
2861 #endif
2862 }
2863 
2864 void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
2865 			   struct sk_buff *skb);
2866 void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
2867 			     struct sk_buff *skb);
2868 
2869 bool skb_has_tx_timestamp(struct sk_buff *skb, const struct sock *sk);
2870 int skb_get_tx_timestamp(struct sk_buff *skb, struct sock *sk,
2871 			 struct timespec64 *ts);
2872 
2873 static inline void
2874 sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
2875 {
2876 	struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
2877 	u32 tsflags = READ_ONCE(sk->sk_tsflags);
2878 	ktime_t kt = skb->tstamp;
2879 	/*
2880 	 * generate control messages if
2881 	 * - receive time stamping in software requested
2882 	 * - software time stamp available and wanted
2883 	 * - hardware time stamps available and wanted
2884 	 */
2885 	if (sock_flag(sk, SOCK_RCVTSTAMP) ||
2886 	    (tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) ||
2887 	    (kt && tsflags & SOF_TIMESTAMPING_SOFTWARE) ||
2888 	    (hwtstamps->hwtstamp &&
2889 	     (tsflags & SOF_TIMESTAMPING_RAW_HARDWARE)))
2890 		__sock_recv_timestamp(msg, sk, skb);
2891 	else
2892 		sock_write_timestamp(sk, kt);
2893 
2894 	if (sock_flag(sk, SOCK_WIFI_STATUS) && skb_wifi_acked_valid(skb))
2895 		__sock_recv_wifi_status(msg, sk, skb);
2896 }
2897 
2898 void __sock_recv_cmsgs(struct msghdr *msg, struct sock *sk,
2899 		       struct sk_buff *skb);
2900 
2901 #define SK_DEFAULT_STAMP (-1L * NSEC_PER_SEC)
2902 static inline void sock_recv_cmsgs(struct msghdr *msg, struct sock *sk,
2903 				   struct sk_buff *skb)
2904 {
2905 #define FLAGS_RECV_CMSGS ((1UL << SOCK_RXQ_OVFL)			| \
2906 			   (1UL << SOCK_RCVTSTAMP)			| \
2907 			   (1UL << SOCK_RCVMARK)			| \
2908 			   (1UL << SOCK_RCVPRIORITY)			| \
2909 			   (1UL << SOCK_TIMESTAMPING_ANY))
2910 #define TSFLAGS_ANY	  (SOF_TIMESTAMPING_SOFTWARE			| \
2911 			   SOF_TIMESTAMPING_RAW_HARDWARE)
2912 
2913 	if (READ_ONCE(sk->sk_flags) & FLAGS_RECV_CMSGS)
2914 		__sock_recv_cmsgs(msg, sk, skb);
2915 	else if (unlikely(sock_flag(sk, SOCK_TIMESTAMP)))
2916 		sock_write_timestamp(sk, skb->tstamp);
2917 	else if (unlikely(sock_read_timestamp(sk) == SK_DEFAULT_STAMP))
2918 		sock_write_timestamp(sk, 0);
2919 }
2920 
2921 void __sock_tx_timestamp(__u32 tsflags, __u8 *tx_flags);
2922 
2923 /**
2924  * _sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
2925  * @sk:		socket sending this packet
2926  * @sockc:	pointer to socket cmsg cookie to get timestamping info
2927  * @tx_flags:	completed with instructions for time stamping
2928  * @tskey:      filled in with next sk_tskey (not for TCP, which uses seqno)
2929  *
2930  * Note: callers should take care of initial ``*tx_flags`` value (usually 0)
2931  */
2932 static inline void _sock_tx_timestamp(struct sock *sk,
2933 				      const struct sockcm_cookie *sockc,
2934 				      __u8 *tx_flags, __u32 *tskey)
2935 {
2936 	__u32 tsflags = sockc->tsflags;
2937 
2938 	if (unlikely(tsflags)) {
2939 		__sock_tx_timestamp(tsflags, tx_flags);
2940 		if (tsflags & SOF_TIMESTAMPING_OPT_ID && tskey &&
2941 		    tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK) {
2942 			if (tsflags & SOCKCM_FLAG_TS_OPT_ID)
2943 				*tskey = sockc->ts_opt_id;
2944 			else
2945 				*tskey = atomic_inc_return(&sk->sk_tskey) - 1;
2946 		}
2947 	}
2948 }
2949 
2950 static inline void sock_tx_timestamp(struct sock *sk,
2951 				     const struct sockcm_cookie *sockc,
2952 				     __u8 *tx_flags)
2953 {
2954 	_sock_tx_timestamp(sk, sockc, tx_flags, NULL);
2955 }
2956 
2957 static inline void skb_setup_tx_timestamp(struct sk_buff *skb,
2958 					  const struct sockcm_cookie *sockc)
2959 {
2960 	_sock_tx_timestamp(skb->sk, sockc, &skb_shinfo(skb)->tx_flags,
2961 			   &skb_shinfo(skb)->tskey);
2962 }
2963 
2964 static inline bool sk_is_inet(const struct sock *sk)
2965 {
2966 	int family = READ_ONCE(sk->sk_family);
2967 
2968 	return family == AF_INET || family == AF_INET6;
2969 }
2970 
2971 static inline bool sk_is_tcp(const struct sock *sk)
2972 {
2973 	return sk_is_inet(sk) &&
2974 	       sk->sk_type == SOCK_STREAM &&
2975 	       sk->sk_protocol == IPPROTO_TCP;
2976 }
2977 
2978 static inline bool sk_is_udp(const struct sock *sk)
2979 {
2980 	return sk_is_inet(sk) &&
2981 	       sk->sk_type == SOCK_DGRAM &&
2982 	       sk->sk_protocol == IPPROTO_UDP;
2983 }
2984 
2985 static inline bool sk_is_unix(const struct sock *sk)
2986 {
2987 	return sk->sk_family == AF_UNIX;
2988 }
2989 
2990 static inline bool sk_is_stream_unix(const struct sock *sk)
2991 {
2992 	return sk_is_unix(sk) && sk->sk_type == SOCK_STREAM;
2993 }
2994 
2995 static inline bool sk_is_vsock(const struct sock *sk)
2996 {
2997 	return sk->sk_family == AF_VSOCK;
2998 }
2999 
3000 static inline bool sk_may_scm_recv(const struct sock *sk)
3001 {
3002 	return (IS_ENABLED(CONFIG_UNIX) && sk->sk_family == AF_UNIX) ||
3003 		sk->sk_family == AF_NETLINK ||
3004 		(IS_ENABLED(CONFIG_BT) && sk->sk_family == AF_BLUETOOTH);
3005 }
3006 
3007 /**
3008  * sk_eat_skb - Release a skb if it is no longer needed
3009  * @sk: socket to eat this skb from
3010  * @skb: socket buffer to eat
3011  *
3012  * This routine must be called with interrupts disabled or with the socket
3013  * locked so that the sk_buff queue operation is ok.
3014 */
3015 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb)
3016 {
3017 	__skb_unlink(skb, &sk->sk_receive_queue);
3018 	__kfree_skb(skb);
3019 }
3020 
3021 static inline bool
3022 skb_sk_is_prefetched(struct sk_buff *skb)
3023 {
3024 #ifdef CONFIG_INET
3025 	return skb->destructor == sock_pfree;
3026 #else
3027 	return false;
3028 #endif /* CONFIG_INET */
3029 }
3030 
3031 /* This helper checks if a socket is a full socket,
3032  * ie _not_ a timewait or request socket.
3033  */
3034 static inline bool sk_fullsock(const struct sock *sk)
3035 {
3036 	return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV);
3037 }
3038 
3039 static inline bool
3040 sk_is_refcounted(struct sock *sk)
3041 {
3042 	/* Only full sockets have sk->sk_flags. */
3043 	return !sk_fullsock(sk) || !sock_flag(sk, SOCK_RCU_FREE);
3044 }
3045 
3046 static inline bool
3047 sk_requests_wifi_status(struct sock *sk)
3048 {
3049 	return sk && sk_fullsock(sk) && sock_flag(sk, SOCK_WIFI_STATUS);
3050 }
3051 
3052 /* This helper checks if a socket is a LISTEN or NEW_SYN_RECV
3053  * SYNACK messages can be attached to either ones (depending on SYNCOOKIE)
3054  */
3055 static inline bool sk_listener(const struct sock *sk)
3056 {
3057 	return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV);
3058 }
3059 
3060 /* This helper checks if a socket is a LISTEN or NEW_SYN_RECV or TIME_WAIT
3061  * TCP SYNACK messages can be attached to LISTEN or NEW_SYN_RECV (depending on SYNCOOKIE)
3062  * TCP RST and ACK can be attached to TIME_WAIT.
3063  */
3064 static inline bool sk_listener_or_tw(const struct sock *sk)
3065 {
3066 	return (1 << READ_ONCE(sk->sk_state)) &
3067 	       (TCPF_LISTEN | TCPF_NEW_SYN_RECV | TCPF_TIME_WAIT);
3068 }
3069 
3070 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag);
3071 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level,
3072 		       int type);
3073 
3074 bool sk_ns_capable(const struct sock *sk,
3075 		   struct user_namespace *user_ns, int cap);
3076 bool sk_capable(const struct sock *sk, int cap);
3077 bool sk_net_capable(const struct sock *sk, int cap);
3078 
3079 void sk_get_meminfo(const struct sock *sk, u32 *meminfo);
3080 
3081 /* Take into consideration the size of the struct sk_buff overhead in the
3082  * determination of these values, since that is non-constant across
3083  * platforms.  This makes socket queueing behavior and performance
3084  * not depend upon such differences.
3085  */
3086 #define _SK_MEM_PACKETS		256
3087 #define _SK_MEM_OVERHEAD	SKB_TRUESIZE(256)
3088 #define SK_WMEM_DEFAULT		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
3089 #define SK_RMEM_DEFAULT		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
3090 
3091 extern __u32 sysctl_wmem_max;
3092 extern __u32 sysctl_rmem_max;
3093 
3094 extern __u32 sysctl_wmem_default;
3095 extern __u32 sysctl_rmem_default;
3096 
3097 #define SKB_FRAG_PAGE_ORDER	get_order(32768)
3098 DECLARE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
3099 
3100 static inline int sk_get_wmem0(const struct sock *sk, const struct proto *proto)
3101 {
3102 	/* Does this proto have per netns sysctl_wmem ? */
3103 	if (proto->sysctl_wmem_offset)
3104 		return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_wmem_offset));
3105 
3106 	return READ_ONCE(*proto->sysctl_wmem);
3107 }
3108 
3109 static inline int sk_get_rmem0(const struct sock *sk, const struct proto *proto)
3110 {
3111 	/* Does this proto have per netns sysctl_rmem ? */
3112 	if (proto->sysctl_rmem_offset)
3113 		return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_rmem_offset));
3114 
3115 	return READ_ONCE(*proto->sysctl_rmem);
3116 }
3117 
3118 /* Default TCP Small queue budget is ~1 ms of data (1sec >> 10)
3119  * Some wifi drivers need to tweak it to get more chunks.
3120  * They can use this helper from their ndo_start_xmit()
3121  */
3122 static inline void sk_pacing_shift_update(struct sock *sk, int val)
3123 {
3124 	if (!sk || !sk_fullsock(sk) || READ_ONCE(sk->sk_pacing_shift) == val)
3125 		return;
3126 	WRITE_ONCE(sk->sk_pacing_shift, val);
3127 }
3128 
3129 /* if a socket is bound to a device, check that the given device
3130  * index is either the same or that the socket is bound to an L3
3131  * master device and the given device index is also enslaved to
3132  * that L3 master
3133  */
3134 static inline bool sk_dev_equal_l3scope(struct sock *sk, int dif)
3135 {
3136 	int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
3137 	int mdif;
3138 
3139 	if (!bound_dev_if || bound_dev_if == dif)
3140 		return true;
3141 
3142 	mdif = l3mdev_master_ifindex_by_index(sock_net(sk), dif);
3143 	if (mdif && mdif == bound_dev_if)
3144 		return true;
3145 
3146 	return false;
3147 }
3148 
3149 void sock_def_readable(struct sock *sk);
3150 
3151 int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk);
3152 void sock_set_timestamp(struct sock *sk, int optname, bool valbool);
3153 int sock_set_timestamping(struct sock *sk, int optname,
3154 			  struct so_timestamping timestamping);
3155 
3156 #if defined(CONFIG_CGROUP_BPF)
3157 void bpf_skops_tx_timestamping(struct sock *sk, struct sk_buff *skb, int op);
3158 #else
3159 static inline void bpf_skops_tx_timestamping(struct sock *sk, struct sk_buff *skb, int op)
3160 {
3161 }
3162 #endif
3163 void sock_no_linger(struct sock *sk);
3164 void sock_set_keepalive(struct sock *sk);
3165 void sock_set_priority(struct sock *sk, u32 priority);
3166 void sock_set_rcvbuf(struct sock *sk, int val);
3167 void sock_set_mark(struct sock *sk, u32 val);
3168 void sock_set_reuseaddr(struct sock *sk);
3169 void sock_set_reuseport(struct sock *sk);
3170 void sock_set_sndtimeo(struct sock *sk, s64 secs);
3171 
3172 int sock_bind_add(struct sock *sk, struct sockaddr_unsized *addr, int addr_len);
3173 
3174 int sock_get_timeout(long timeo, void *optval, bool old_timeval);
3175 int sock_copy_user_timeval(struct __kernel_sock_timeval *tv,
3176 			   sockptr_t optval, int optlen, bool old_timeval);
3177 
3178 int sock_ioctl_inout(struct sock *sk, unsigned int cmd,
3179 		     void __user *arg, void *karg, size_t size);
3180 int sk_ioctl(struct sock *sk, unsigned int cmd, void __user *arg);
3181 static inline bool sk_is_readable(struct sock *sk)
3182 {
3183 	const struct proto *prot = READ_ONCE(sk->sk_prot);
3184 
3185 	if (prot->sock_is_readable)
3186 		return prot->sock_is_readable(sk);
3187 
3188 	return false;
3189 }
3190 #endif	/* _SOCK_H */
3191