xref: /OK3568_Linux_fs/kernel/include/net/sock.h (revision 4882a59341e53eb6f0b4789bf948001014eff981)
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/filter.h>
60 #include <linux/rculist_nulls.h>
61 #include <linux/poll.h>
62 #include <linux/sockptr.h>
63 
64 #include <linux/atomic.h>
65 #include <linux/refcount.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 <linux/android_kabi.h>
72 #include <linux/android_vendor.h>
73 
74 /*
75  * This structure really needs to be cleaned up.
76  * Most of it is for TCP, and not used by any of
77  * the other protocols.
78  */
79 
80 /* Define this to get the SOCK_DBG debugging facility. */
81 #define SOCK_DEBUGGING
82 #ifdef SOCK_DEBUGGING
83 #define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \
84 					printk(KERN_DEBUG msg); } while (0)
85 #else
86 /* Validate arguments and do nothing */
87 static inline __printf(2, 3)
SOCK_DEBUG(const struct sock * sk,const char * msg,...)88 void SOCK_DEBUG(const struct sock *sk, const char *msg, ...)
89 {
90 }
91 #endif
92 
93 /* This is the per-socket lock.  The spinlock provides a synchronization
94  * between user contexts and software interrupt processing, whereas the
95  * mini-semaphore synchronizes multiple users amongst themselves.
96  */
97 typedef struct {
98 	spinlock_t		slock;
99 	int			owned;
100 	wait_queue_head_t	wq;
101 	/*
102 	 * We express the mutex-alike socket_lock semantics
103 	 * to the lock validator by explicitly managing
104 	 * the slock as a lock variant (in addition to
105 	 * the slock itself):
106 	 */
107 #ifdef CONFIG_DEBUG_LOCK_ALLOC
108 	struct lockdep_map dep_map;
109 #endif
110 } socket_lock_t;
111 
112 struct sock;
113 struct proto;
114 struct net;
115 
116 typedef __u32 __bitwise __portpair;
117 typedef __u64 __bitwise __addrpair;
118 
119 /**
120  *	struct sock_common - minimal network layer representation of sockets
121  *	@skc_daddr: Foreign IPv4 addr
122  *	@skc_rcv_saddr: Bound local IPv4 addr
123  *	@skc_addrpair: 8-byte-aligned __u64 union of @skc_daddr & @skc_rcv_saddr
124  *	@skc_hash: hash value used with various protocol lookup tables
125  *	@skc_u16hashes: two u16 hash values used by UDP lookup tables
126  *	@skc_dport: placeholder for inet_dport/tw_dport
127  *	@skc_num: placeholder for inet_num/tw_num
128  *	@skc_portpair: __u32 union of @skc_dport & @skc_num
129  *	@skc_family: network address family
130  *	@skc_state: Connection state
131  *	@skc_reuse: %SO_REUSEADDR setting
132  *	@skc_reuseport: %SO_REUSEPORT setting
133  *	@skc_ipv6only: socket is IPV6 only
134  *	@skc_net_refcnt: socket is using net ref counting
135  *	@skc_bound_dev_if: bound device index if != 0
136  *	@skc_bind_node: bind hash linkage for various protocol lookup tables
137  *	@skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol
138  *	@skc_prot: protocol handlers inside a network family
139  *	@skc_net: reference to the network namespace of this socket
140  *	@skc_v6_daddr: IPV6 destination address
141  *	@skc_v6_rcv_saddr: IPV6 source address
142  *	@skc_cookie: socket's cookie value
143  *	@skc_node: main hash linkage for various protocol lookup tables
144  *	@skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol
145  *	@skc_tx_queue_mapping: tx queue number for this connection
146  *	@skc_rx_queue_mapping: rx queue number for this connection
147  *	@skc_flags: place holder for sk_flags
148  *		%SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE,
149  *		%SO_OOBINLINE settings, %SO_TIMESTAMPING settings
150  *	@skc_listener: connection request listener socket (aka rsk_listener)
151  *		[union with @skc_flags]
152  *	@skc_tw_dr: (aka tw_dr) ptr to &struct inet_timewait_death_row
153  *		[union with @skc_flags]
154  *	@skc_incoming_cpu: record/match cpu processing incoming packets
155  *	@skc_rcv_wnd: (aka rsk_rcv_wnd) TCP receive window size (possibly scaled)
156  *		[union with @skc_incoming_cpu]
157  *	@skc_tw_rcv_nxt: (aka tw_rcv_nxt) TCP window next expected seq number
158  *		[union with @skc_incoming_cpu]
159  *	@skc_refcnt: reference count
160  *
161  *	This is the minimal network layer representation of sockets, the header
162  *	for struct sock and struct inet_timewait_sock.
163  */
164 struct sock_common {
165 	union {
166 		__addrpair	skc_addrpair;
167 		struct {
168 			__be32	skc_daddr;
169 			__be32	skc_rcv_saddr;
170 		};
171 	};
172 	union  {
173 		unsigned int	skc_hash;
174 		__u16		skc_u16hashes[2];
175 	};
176 	/* skc_dport && skc_num must be grouped as well */
177 	union {
178 		__portpair	skc_portpair;
179 		struct {
180 			__be16	skc_dport;
181 			__u16	skc_num;
182 		};
183 	};
184 
185 	unsigned short		skc_family;
186 	volatile unsigned char	skc_state;
187 	unsigned char		skc_reuse:4;
188 	unsigned char		skc_reuseport:1;
189 	unsigned char		skc_ipv6only:1;
190 	unsigned char		skc_net_refcnt:1;
191 	int			skc_bound_dev_if;
192 	union {
193 		struct hlist_node	skc_bind_node;
194 		struct hlist_node	skc_portaddr_node;
195 	};
196 	struct proto		*skc_prot;
197 	possible_net_t		skc_net;
198 
199 #if IS_ENABLED(CONFIG_IPV6)
200 	struct in6_addr		skc_v6_daddr;
201 	struct in6_addr		skc_v6_rcv_saddr;
202 #endif
203 
204 	atomic64_t		skc_cookie;
205 
206 	/* following fields are padding to force
207 	 * offset(struct sock, sk_refcnt) == 128 on 64bit arches
208 	 * assuming IPV6 is enabled. We use this padding differently
209 	 * for different kind of 'sockets'
210 	 */
211 	union {
212 		unsigned long	skc_flags;
213 		struct sock	*skc_listener; /* request_sock */
214 		struct inet_timewait_death_row *skc_tw_dr; /* inet_timewait_sock */
215 	};
216 	/*
217 	 * fields between dontcopy_begin/dontcopy_end
218 	 * are not copied in sock_copy()
219 	 */
220 	/* private: */
221 	int			skc_dontcopy_begin[0];
222 	/* public: */
223 	union {
224 		struct hlist_node	skc_node;
225 		struct hlist_nulls_node skc_nulls_node;
226 	};
227 	unsigned short		skc_tx_queue_mapping;
228 #ifdef CONFIG_XPS
229 	unsigned short		skc_rx_queue_mapping;
230 #endif
231 	union {
232 		int		skc_incoming_cpu;
233 		u32		skc_rcv_wnd;
234 		u32		skc_tw_rcv_nxt; /* struct tcp_timewait_sock  */
235 	};
236 
237 	refcount_t		skc_refcnt;
238 	/* private: */
239 	int                     skc_dontcopy_end[0];
240 	union {
241 		u32		skc_rxhash;
242 		u32		skc_window_clamp;
243 		u32		skc_tw_snd_nxt; /* struct tcp_timewait_sock */
244 	};
245 	/* public: */
246 };
247 
248 struct bpf_local_storage;
249 
250 /**
251   *	struct sock - network layer representation of sockets
252   *	@__sk_common: shared layout with inet_timewait_sock
253   *	@sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
254   *	@sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
255   *	@sk_lock:	synchronizer
256   *	@sk_kern_sock: True if sock is using kernel lock classes
257   *	@sk_rcvbuf: size of receive buffer in bytes
258   *	@sk_wq: sock wait queue and async head
259   *	@sk_rx_dst: receive input route used by early demux
260   *	@sk_dst_cache: destination cache
261   *	@sk_dst_pending_confirm: need to confirm neighbour
262   *	@sk_policy: flow policy
263   *	@sk_rx_skb_cache: cache copy of recently accessed RX skb
264   *	@sk_receive_queue: incoming packets
265   *	@sk_wmem_alloc: transmit queue bytes committed
266   *	@sk_tsq_flags: TCP Small Queues flags
267   *	@sk_write_queue: Packet sending queue
268   *	@sk_omem_alloc: "o" is "option" or "other"
269   *	@sk_wmem_queued: persistent queue size
270   *	@sk_forward_alloc: space allocated forward
271   *	@sk_napi_id: id of the last napi context to receive data for sk
272   *	@sk_ll_usec: usecs to busypoll when there is no data
273   *	@sk_allocation: allocation mode
274   *	@sk_pacing_rate: Pacing rate (if supported by transport/packet scheduler)
275   *	@sk_pacing_status: Pacing status (requested, handled by sch_fq)
276   *	@sk_max_pacing_rate: Maximum pacing rate (%SO_MAX_PACING_RATE)
277   *	@sk_sndbuf: size of send buffer in bytes
278   *	@__sk_flags_offset: empty field used to determine location of bitfield
279   *	@sk_padding: unused element for alignment
280   *	@sk_no_check_tx: %SO_NO_CHECK setting, set checksum in TX packets
281   *	@sk_no_check_rx: allow zero checksum in RX packets
282   *	@sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
283   *	@sk_route_nocaps: forbidden route capabilities (e.g NETIF_F_GSO_MASK)
284   *	@sk_route_forced_caps: static, forced route capabilities
285   *		(set in tcp_init_sock())
286   *	@sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
287   *	@sk_gso_max_size: Maximum GSO segment size to build
288   *	@sk_gso_max_segs: Maximum number of GSO segments
289   *	@sk_pacing_shift: scaling factor for TCP Small Queues
290   *	@sk_lingertime: %SO_LINGER l_linger setting
291   *	@sk_backlog: always used with the per-socket spinlock held
292   *	@sk_callback_lock: used with the callbacks in the end of this struct
293   *	@sk_error_queue: rarely used
294   *	@sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt,
295   *			  IPV6_ADDRFORM for instance)
296   *	@sk_err: last error
297   *	@sk_err_soft: errors that don't cause failure but are the cause of a
298   *		      persistent failure not just 'timed out'
299   *	@sk_drops: raw/udp drops counter
300   *	@sk_ack_backlog: current listen backlog
301   *	@sk_max_ack_backlog: listen backlog set in listen()
302   *	@sk_uid: user id of owner
303   *	@sk_priority: %SO_PRIORITY setting
304   *	@sk_type: socket type (%SOCK_STREAM, etc)
305   *	@sk_protocol: which protocol this socket belongs in this network family
306   *	@sk_peer_pid: &struct pid for this socket's peer
307   *	@sk_peer_cred: %SO_PEERCRED setting
308   *	@sk_rcvlowat: %SO_RCVLOWAT setting
309   *	@sk_rcvtimeo: %SO_RCVTIMEO setting
310   *	@sk_sndtimeo: %SO_SNDTIMEO setting
311   *	@sk_txhash: computed flow hash for use on transmit
312   *	@sk_filter: socket filtering instructions
313   *	@sk_timer: sock cleanup timer
314   *	@sk_stamp: time stamp of last packet received
315   *	@sk_stamp_seq: lock for accessing sk_stamp on 32 bit architectures only
316   *	@sk_tsflags: SO_TIMESTAMPING socket options
317   *	@sk_tskey: counter to disambiguate concurrent tstamp requests
318   *	@sk_zckey: counter to order MSG_ZEROCOPY notifications
319   *	@sk_socket: Identd and reporting IO signals
320   *	@sk_user_data: RPC layer private data
321   *	@sk_frag: cached page frag
322   *	@sk_peek_off: current peek_offset value
323   *	@sk_send_head: front of stuff to transmit
324   *	@tcp_rtx_queue: TCP re-transmit queue [union with @sk_send_head]
325   *	@sk_tx_skb_cache: cache copy of recently accessed TX skb
326   *	@sk_security: used by security modules
327   *	@sk_mark: generic packet mark
328   *	@sk_cgrp_data: cgroup data for this cgroup
329   *	@sk_memcg: this socket's memory cgroup association
330   *	@sk_write_pending: a write to stream socket waits to start
331   *	@sk_state_change: callback to indicate change in the state of the sock
332   *	@sk_data_ready: callback to indicate there is data to be processed
333   *	@sk_write_space: callback to indicate there is bf sending space available
334   *	@sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
335   *	@sk_backlog_rcv: callback to process the backlog
336   *	@sk_validate_xmit_skb: ptr to an optional validate function
337   *	@sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
338   *	@sk_reuseport_cb: reuseport group container
339   *	@sk_bpf_storage: ptr to cache and control for bpf_sk_storage
340   *	@sk_rcu: used during RCU grace period
341   *	@sk_clockid: clockid used by time-based scheduling (SO_TXTIME)
342   *	@sk_txtime_deadline_mode: set deadline mode for SO_TXTIME
343   *	@sk_txtime_report_errors: set report errors mode for SO_TXTIME
344   *	@sk_txtime_unused: unused txtime flags
345   */
346 struct sock {
347 	/*
348 	 * Now struct inet_timewait_sock also uses sock_common, so please just
349 	 * don't add nothing before this first member (__sk_common) --acme
350 	 */
351 	struct sock_common	__sk_common;
352 #define sk_node			__sk_common.skc_node
353 #define sk_nulls_node		__sk_common.skc_nulls_node
354 #define sk_refcnt		__sk_common.skc_refcnt
355 #define sk_tx_queue_mapping	__sk_common.skc_tx_queue_mapping
356 #ifdef CONFIG_XPS
357 #define sk_rx_queue_mapping	__sk_common.skc_rx_queue_mapping
358 #endif
359 
360 #define sk_dontcopy_begin	__sk_common.skc_dontcopy_begin
361 #define sk_dontcopy_end		__sk_common.skc_dontcopy_end
362 #define sk_hash			__sk_common.skc_hash
363 #define sk_portpair		__sk_common.skc_portpair
364 #define sk_num			__sk_common.skc_num
365 #define sk_dport		__sk_common.skc_dport
366 #define sk_addrpair		__sk_common.skc_addrpair
367 #define sk_daddr		__sk_common.skc_daddr
368 #define sk_rcv_saddr		__sk_common.skc_rcv_saddr
369 #define sk_family		__sk_common.skc_family
370 #define sk_state		__sk_common.skc_state
371 #define sk_reuse		__sk_common.skc_reuse
372 #define sk_reuseport		__sk_common.skc_reuseport
373 #define sk_ipv6only		__sk_common.skc_ipv6only
374 #define sk_net_refcnt		__sk_common.skc_net_refcnt
375 #define sk_bound_dev_if		__sk_common.skc_bound_dev_if
376 #define sk_bind_node		__sk_common.skc_bind_node
377 #define sk_prot			__sk_common.skc_prot
378 #define sk_net			__sk_common.skc_net
379 #define sk_v6_daddr		__sk_common.skc_v6_daddr
380 #define sk_v6_rcv_saddr	__sk_common.skc_v6_rcv_saddr
381 #define sk_cookie		__sk_common.skc_cookie
382 #define sk_incoming_cpu		__sk_common.skc_incoming_cpu
383 #define sk_flags		__sk_common.skc_flags
384 #define sk_rxhash		__sk_common.skc_rxhash
385 
386 	socket_lock_t		sk_lock;
387 	atomic_t		sk_drops;
388 	int			sk_rcvlowat;
389 	struct sk_buff_head	sk_error_queue;
390 	struct sk_buff		*sk_rx_skb_cache;
391 	struct sk_buff_head	sk_receive_queue;
392 	/*
393 	 * The backlog queue is special, it is always used with
394 	 * the per-socket spinlock held and requires low latency
395 	 * access. Therefore we special case it's implementation.
396 	 * Note : rmem_alloc is in this structure to fill a hole
397 	 * on 64bit arches, not because its logically part of
398 	 * backlog.
399 	 */
400 	struct {
401 		atomic_t	rmem_alloc;
402 		int		len;
403 		struct sk_buff	*head;
404 		struct sk_buff	*tail;
405 	} sk_backlog;
406 #define sk_rmem_alloc sk_backlog.rmem_alloc
407 
408 	int			sk_forward_alloc;
409 #ifdef CONFIG_NET_RX_BUSY_POLL
410 	unsigned int		sk_ll_usec;
411 	/* ===== mostly read cache line ===== */
412 	unsigned int		sk_napi_id;
413 #endif
414 	int			sk_rcvbuf;
415 
416 	struct sk_filter __rcu	*sk_filter;
417 	union {
418 		struct socket_wq __rcu	*sk_wq;
419 		/* private: */
420 		struct socket_wq	*sk_wq_raw;
421 		/* public: */
422 	};
423 #ifdef CONFIG_XFRM
424 	struct xfrm_policy __rcu *sk_policy[2];
425 #endif
426 	struct dst_entry __rcu	*sk_rx_dst;
427 	struct dst_entry __rcu	*sk_dst_cache;
428 	atomic_t		sk_omem_alloc;
429 	int			sk_sndbuf;
430 
431 	/* ===== cache line for TX ===== */
432 	int			sk_wmem_queued;
433 	refcount_t		sk_wmem_alloc;
434 	unsigned long		sk_tsq_flags;
435 	union {
436 		struct sk_buff	*sk_send_head;
437 		struct rb_root	tcp_rtx_queue;
438 	};
439 	struct sk_buff		*sk_tx_skb_cache;
440 	struct sk_buff_head	sk_write_queue;
441 	__s32			sk_peek_off;
442 	int			sk_write_pending;
443 	__u32			sk_dst_pending_confirm;
444 	u32			sk_pacing_status; /* see enum sk_pacing */
445 	long			sk_sndtimeo;
446 	struct timer_list	sk_timer;
447 	__u32			sk_priority;
448 	__u32			sk_mark;
449 	unsigned long		sk_pacing_rate; /* bytes per second */
450 	unsigned long		sk_max_pacing_rate;
451 	struct page_frag	sk_frag;
452 	netdev_features_t	sk_route_caps;
453 	netdev_features_t	sk_route_nocaps;
454 	netdev_features_t	sk_route_forced_caps;
455 	int			sk_gso_type;
456 	unsigned int		sk_gso_max_size;
457 	gfp_t			sk_allocation;
458 	__u32			sk_txhash;
459 
460 	/*
461 	 * Because of non atomicity rules, all
462 	 * changes are protected by socket lock.
463 	 */
464 	u8			sk_padding : 1,
465 				sk_kern_sock : 1,
466 				sk_no_check_tx : 1,
467 				sk_no_check_rx : 1,
468 				sk_userlocks : 4;
469 	u8			sk_pacing_shift;
470 	u16			sk_type;
471 	u16			sk_protocol;
472 	u16			sk_gso_max_segs;
473 	unsigned long	        sk_lingertime;
474 	struct proto		*sk_prot_creator;
475 	rwlock_t		sk_callback_lock;
476 	int			sk_err,
477 				sk_err_soft;
478 	u32			sk_ack_backlog;
479 	u32			sk_max_ack_backlog;
480 	kuid_t			sk_uid;
481 #if IS_ENABLED(CONFIG_DEBUG_SPINLOCK) || IS_ENABLED(CONFIG_DEBUG_LOCK_ALLOC)
482 	spinlock_t		sk_peer_lock;
483 #else
484 	/* sk_peer_lock is in the ANDROID_KABI_RESERVE(1) field below */
485 #endif
486 	struct pid		*sk_peer_pid;
487 	const struct cred	*sk_peer_cred;
488 
489 	long			sk_rcvtimeo;
490 	ktime_t			sk_stamp;
491 #if BITS_PER_LONG==32
492 	seqlock_t		sk_stamp_seq;
493 #endif
494 	u16			sk_tsflags;
495 	u8			sk_shutdown;
496 	u32			sk_tskey;
497 	atomic_t		sk_zckey;
498 
499 	u8			sk_clockid;
500 	u8			sk_txtime_deadline_mode : 1,
501 				sk_txtime_report_errors : 1,
502 				sk_txtime_unused : 6;
503 
504 	struct socket		*sk_socket;
505 	void			*sk_user_data;
506 #ifdef CONFIG_SECURITY
507 	void			*sk_security;
508 #endif
509 	struct sock_cgroup_data	sk_cgrp_data;
510 	struct mem_cgroup	*sk_memcg;
511 	void			(*sk_state_change)(struct sock *sk);
512 	void			(*sk_data_ready)(struct sock *sk);
513 	void			(*sk_write_space)(struct sock *sk);
514 	void			(*sk_error_report)(struct sock *sk);
515 	int			(*sk_backlog_rcv)(struct sock *sk,
516 						  struct sk_buff *skb);
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 	void                    (*sk_destruct)(struct sock *sk);
523 	struct sock_reuseport __rcu	*sk_reuseport_cb;
524 #ifdef CONFIG_BPF_SYSCALL
525 	struct bpf_local_storage __rcu	*sk_bpf_storage;
526 #endif
527 	struct rcu_head		sk_rcu;
528 
529 #if IS_ENABLED(CONFIG_DEBUG_SPINLOCK) || IS_ENABLED(CONFIG_DEBUG_LOCK_ALLOC)
530 	ANDROID_KABI_RESERVE(1);
531 #else
532 	ANDROID_KABI_USE(1, spinlock_t sk_peer_lock);
533 #endif
534 	ANDROID_KABI_RESERVE(2);
535 	ANDROID_KABI_RESERVE(3);
536 	ANDROID_KABI_RESERVE(4);
537 	ANDROID_KABI_RESERVE(5);
538 	ANDROID_KABI_RESERVE(6);
539 	ANDROID_KABI_RESERVE(7);
540 	ANDROID_KABI_RESERVE(8);
541 
542 	ANDROID_OEM_DATA(1);
543 };
544 
545 enum sk_pacing {
546 	SK_PACING_NONE		= 0,
547 	SK_PACING_NEEDED	= 1,
548 	SK_PACING_FQ		= 2,
549 };
550 
551 /* flag bits in sk_user_data
552  *
553  * - SK_USER_DATA_NOCOPY:      Pointer stored in sk_user_data might
554  *   not be suitable for copying when cloning the socket. For instance,
555  *   it can point to a reference counted object. sk_user_data bottom
556  *   bit is set if pointer must not be copied.
557  *
558  * - SK_USER_DATA_BPF:         Mark whether sk_user_data field is
559  *   managed/owned by a BPF reuseport array. This bit should be set
560  *   when sk_user_data's sk is added to the bpf's reuseport_array.
561  *
562  * - SK_USER_DATA_PSOCK:       Mark whether pointer stored in
563  *   sk_user_data points to psock type. This bit should be set
564  *   when sk_user_data is assigned to a psock object.
565  */
566 #define SK_USER_DATA_NOCOPY	1UL
567 #define SK_USER_DATA_BPF	2UL
568 #define SK_USER_DATA_PSOCK	4UL
569 #define SK_USER_DATA_PTRMASK	~(SK_USER_DATA_NOCOPY | SK_USER_DATA_BPF |\
570 				  SK_USER_DATA_PSOCK)
571 
572 /**
573  * sk_user_data_is_nocopy - Test if sk_user_data pointer must not be copied
574  * @sk: socket
575  */
sk_user_data_is_nocopy(const struct sock * sk)576 static inline bool sk_user_data_is_nocopy(const struct sock *sk)
577 {
578 	return ((uintptr_t)sk->sk_user_data & SK_USER_DATA_NOCOPY);
579 }
580 
581 #define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data)))
582 
583 /**
584  * __rcu_dereference_sk_user_data_with_flags - return the pointer
585  * only if argument flags all has been set in sk_user_data. Otherwise
586  * return NULL
587  *
588  * @sk: socket
589  * @flags: flag bits
590  */
591 static inline void *
__rcu_dereference_sk_user_data_with_flags(const struct sock * sk,uintptr_t flags)592 __rcu_dereference_sk_user_data_with_flags(const struct sock *sk,
593 					  uintptr_t flags)
594 {
595 	uintptr_t sk_user_data = (uintptr_t)rcu_dereference(__sk_user_data(sk));
596 
597 	WARN_ON_ONCE(flags & SK_USER_DATA_PTRMASK);
598 
599 	if ((sk_user_data & flags) == flags)
600 		return (void *)(sk_user_data & SK_USER_DATA_PTRMASK);
601 	return NULL;
602 }
603 
604 #define rcu_dereference_sk_user_data(sk)				\
605 	__rcu_dereference_sk_user_data_with_flags(sk, 0)
606 #define __rcu_assign_sk_user_data_with_flags(sk, ptr, flags)		\
607 ({									\
608 	uintptr_t __tmp1 = (uintptr_t)(ptr),				\
609 		  __tmp2 = (uintptr_t)(flags);				\
610 	WARN_ON_ONCE(__tmp1 & ~SK_USER_DATA_PTRMASK);			\
611 	WARN_ON_ONCE(__tmp2 & SK_USER_DATA_PTRMASK);			\
612 	rcu_assign_pointer(__sk_user_data((sk)),			\
613 			   __tmp1 | __tmp2);				\
614 })
615 #define rcu_assign_sk_user_data(sk, ptr)				\
616 	__rcu_assign_sk_user_data_with_flags(sk, ptr, 0)
617 
618 /*
619  * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK
620  * or not whether his port will be reused by someone else. SK_FORCE_REUSE
621  * on a socket means that the socket will reuse everybody else's port
622  * without looking at the other's sk_reuse value.
623  */
624 
625 #define SK_NO_REUSE	0
626 #define SK_CAN_REUSE	1
627 #define SK_FORCE_REUSE	2
628 
629 int sk_set_peek_off(struct sock *sk, int val);
630 
sk_peek_offset(struct sock * sk,int flags)631 static inline int sk_peek_offset(struct sock *sk, int flags)
632 {
633 	if (unlikely(flags & MSG_PEEK)) {
634 		return READ_ONCE(sk->sk_peek_off);
635 	}
636 
637 	return 0;
638 }
639 
sk_peek_offset_bwd(struct sock * sk,int val)640 static inline void sk_peek_offset_bwd(struct sock *sk, int val)
641 {
642 	s32 off = READ_ONCE(sk->sk_peek_off);
643 
644 	if (unlikely(off >= 0)) {
645 		off = max_t(s32, off - val, 0);
646 		WRITE_ONCE(sk->sk_peek_off, off);
647 	}
648 }
649 
sk_peek_offset_fwd(struct sock * sk,int val)650 static inline void sk_peek_offset_fwd(struct sock *sk, int val)
651 {
652 	sk_peek_offset_bwd(sk, -val);
653 }
654 
655 /*
656  * Hashed lists helper routines
657  */
sk_entry(const struct hlist_node * node)658 static inline struct sock *sk_entry(const struct hlist_node *node)
659 {
660 	return hlist_entry(node, struct sock, sk_node);
661 }
662 
__sk_head(const struct hlist_head * head)663 static inline struct sock *__sk_head(const struct hlist_head *head)
664 {
665 	return hlist_entry(head->first, struct sock, sk_node);
666 }
667 
sk_head(const struct hlist_head * head)668 static inline struct sock *sk_head(const struct hlist_head *head)
669 {
670 	return hlist_empty(head) ? NULL : __sk_head(head);
671 }
672 
__sk_nulls_head(const struct hlist_nulls_head * head)673 static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head)
674 {
675 	return hlist_nulls_entry(head->first, struct sock, sk_nulls_node);
676 }
677 
sk_nulls_head(const struct hlist_nulls_head * head)678 static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head)
679 {
680 	return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head);
681 }
682 
sk_next(const struct sock * sk)683 static inline struct sock *sk_next(const struct sock *sk)
684 {
685 	return hlist_entry_safe(sk->sk_node.next, struct sock, sk_node);
686 }
687 
sk_nulls_next(const struct sock * sk)688 static inline struct sock *sk_nulls_next(const struct sock *sk)
689 {
690 	return (!is_a_nulls(sk->sk_nulls_node.next)) ?
691 		hlist_nulls_entry(sk->sk_nulls_node.next,
692 				  struct sock, sk_nulls_node) :
693 		NULL;
694 }
695 
sk_unhashed(const struct sock * sk)696 static inline bool sk_unhashed(const struct sock *sk)
697 {
698 	return hlist_unhashed(&sk->sk_node);
699 }
700 
sk_hashed(const struct sock * sk)701 static inline bool sk_hashed(const struct sock *sk)
702 {
703 	return !sk_unhashed(sk);
704 }
705 
sk_node_init(struct hlist_node * node)706 static inline void sk_node_init(struct hlist_node *node)
707 {
708 	node->pprev = NULL;
709 }
710 
sk_nulls_node_init(struct hlist_nulls_node * node)711 static inline void sk_nulls_node_init(struct hlist_nulls_node *node)
712 {
713 	node->pprev = NULL;
714 }
715 
__sk_del_node(struct sock * sk)716 static inline void __sk_del_node(struct sock *sk)
717 {
718 	__hlist_del(&sk->sk_node);
719 }
720 
721 /* NB: equivalent to hlist_del_init_rcu */
__sk_del_node_init(struct sock * sk)722 static inline bool __sk_del_node_init(struct sock *sk)
723 {
724 	if (sk_hashed(sk)) {
725 		__sk_del_node(sk);
726 		sk_node_init(&sk->sk_node);
727 		return true;
728 	}
729 	return false;
730 }
731 
732 /* Grab socket reference count. This operation is valid only
733    when sk is ALREADY grabbed f.e. it is found in hash table
734    or a list and the lookup is made under lock preventing hash table
735    modifications.
736  */
737 
sock_hold(struct sock * sk)738 static __always_inline void sock_hold(struct sock *sk)
739 {
740 	refcount_inc(&sk->sk_refcnt);
741 }
742 
743 /* Ungrab socket in the context, which assumes that socket refcnt
744    cannot hit zero, f.e. it is true in context of any socketcall.
745  */
__sock_put(struct sock * sk)746 static __always_inline void __sock_put(struct sock *sk)
747 {
748 	refcount_dec(&sk->sk_refcnt);
749 }
750 
sk_del_node_init(struct sock * sk)751 static inline bool sk_del_node_init(struct sock *sk)
752 {
753 	bool rc = __sk_del_node_init(sk);
754 
755 	if (rc) {
756 		/* paranoid for a while -acme */
757 		WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
758 		__sock_put(sk);
759 	}
760 	return rc;
761 }
762 #define sk_del_node_init_rcu(sk)	sk_del_node_init(sk)
763 
__sk_nulls_del_node_init_rcu(struct sock * sk)764 static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk)
765 {
766 	if (sk_hashed(sk)) {
767 		hlist_nulls_del_init_rcu(&sk->sk_nulls_node);
768 		return true;
769 	}
770 	return false;
771 }
772 
sk_nulls_del_node_init_rcu(struct sock * sk)773 static inline bool sk_nulls_del_node_init_rcu(struct sock *sk)
774 {
775 	bool rc = __sk_nulls_del_node_init_rcu(sk);
776 
777 	if (rc) {
778 		/* paranoid for a while -acme */
779 		WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
780 		__sock_put(sk);
781 	}
782 	return rc;
783 }
784 
__sk_add_node(struct sock * sk,struct hlist_head * list)785 static inline void __sk_add_node(struct sock *sk, struct hlist_head *list)
786 {
787 	hlist_add_head(&sk->sk_node, list);
788 }
789 
sk_add_node(struct sock * sk,struct hlist_head * list)790 static inline void sk_add_node(struct sock *sk, struct hlist_head *list)
791 {
792 	sock_hold(sk);
793 	__sk_add_node(sk, list);
794 }
795 
sk_add_node_rcu(struct sock * sk,struct hlist_head * list)796 static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list)
797 {
798 	sock_hold(sk);
799 	if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport &&
800 	    sk->sk_family == AF_INET6)
801 		hlist_add_tail_rcu(&sk->sk_node, list);
802 	else
803 		hlist_add_head_rcu(&sk->sk_node, list);
804 }
805 
sk_add_node_tail_rcu(struct sock * sk,struct hlist_head * list)806 static inline void sk_add_node_tail_rcu(struct sock *sk, struct hlist_head *list)
807 {
808 	sock_hold(sk);
809 	hlist_add_tail_rcu(&sk->sk_node, list);
810 }
811 
__sk_nulls_add_node_rcu(struct sock * sk,struct hlist_nulls_head * list)812 static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
813 {
814 	hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list);
815 }
816 
__sk_nulls_add_node_tail_rcu(struct sock * sk,struct hlist_nulls_head * list)817 static inline void __sk_nulls_add_node_tail_rcu(struct sock *sk, struct hlist_nulls_head *list)
818 {
819 	hlist_nulls_add_tail_rcu(&sk->sk_nulls_node, list);
820 }
821 
sk_nulls_add_node_rcu(struct sock * sk,struct hlist_nulls_head * list)822 static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
823 {
824 	sock_hold(sk);
825 	__sk_nulls_add_node_rcu(sk, list);
826 }
827 
__sk_del_bind_node(struct sock * sk)828 static inline void __sk_del_bind_node(struct sock *sk)
829 {
830 	__hlist_del(&sk->sk_bind_node);
831 }
832 
sk_add_bind_node(struct sock * sk,struct hlist_head * list)833 static inline void sk_add_bind_node(struct sock *sk,
834 					struct hlist_head *list)
835 {
836 	hlist_add_head(&sk->sk_bind_node, list);
837 }
838 
839 #define sk_for_each(__sk, list) \
840 	hlist_for_each_entry(__sk, list, sk_node)
841 #define sk_for_each_rcu(__sk, list) \
842 	hlist_for_each_entry_rcu(__sk, list, sk_node)
843 #define sk_nulls_for_each(__sk, node, list) \
844 	hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)
845 #define sk_nulls_for_each_rcu(__sk, node, list) \
846 	hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)
847 #define sk_for_each_from(__sk) \
848 	hlist_for_each_entry_from(__sk, sk_node)
849 #define sk_nulls_for_each_from(__sk, node) \
850 	if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \
851 		hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node)
852 #define sk_for_each_safe(__sk, tmp, list) \
853 	hlist_for_each_entry_safe(__sk, tmp, list, sk_node)
854 #define sk_for_each_bound(__sk, list) \
855 	hlist_for_each_entry(__sk, list, sk_bind_node)
856 
857 /**
858  * sk_for_each_entry_offset_rcu - iterate over a list at a given struct offset
859  * @tpos:	the type * to use as a loop cursor.
860  * @pos:	the &struct hlist_node to use as a loop cursor.
861  * @head:	the head for your list.
862  * @offset:	offset of hlist_node within the struct.
863  *
864  */
865 #define sk_for_each_entry_offset_rcu(tpos, pos, head, offset)		       \
866 	for (pos = rcu_dereference(hlist_first_rcu(head));		       \
867 	     pos != NULL &&						       \
868 		({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;});       \
869 	     pos = rcu_dereference(hlist_next_rcu(pos)))
870 
sk_user_ns(struct sock * sk)871 static inline struct user_namespace *sk_user_ns(struct sock *sk)
872 {
873 	/* Careful only use this in a context where these parameters
874 	 * can not change and must all be valid, such as recvmsg from
875 	 * userspace.
876 	 */
877 	return sk->sk_socket->file->f_cred->user_ns;
878 }
879 
880 /* Sock flags */
881 enum sock_flags {
882 	SOCK_DEAD,
883 	SOCK_DONE,
884 	SOCK_URGINLINE,
885 	SOCK_KEEPOPEN,
886 	SOCK_LINGER,
887 	SOCK_DESTROY,
888 	SOCK_BROADCAST,
889 	SOCK_TIMESTAMP,
890 	SOCK_ZAPPED,
891 	SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */
892 	SOCK_DBG, /* %SO_DEBUG setting */
893 	SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
894 	SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */
895 	SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
896 	SOCK_MEMALLOC, /* VM depends on this socket for swapping */
897 	SOCK_TIMESTAMPING_RX_SOFTWARE,  /* %SOF_TIMESTAMPING_RX_SOFTWARE */
898 	SOCK_FASYNC, /* fasync() active */
899 	SOCK_RXQ_OVFL,
900 	SOCK_ZEROCOPY, /* buffers from userspace */
901 	SOCK_WIFI_STATUS, /* push wifi status to userspace */
902 	SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS.
903 		     * Will use last 4 bytes of packet sent from
904 		     * user-space instead.
905 		     */
906 	SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */
907 	SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */
908 	SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */
909 	SOCK_TXTIME,
910 	SOCK_XDP, /* XDP is attached */
911 	SOCK_TSTAMP_NEW, /* Indicates 64 bit timestamps always */
912 };
913 
914 #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))
915 
sock_copy_flags(struct sock * nsk,struct sock * osk)916 static inline void sock_copy_flags(struct sock *nsk, struct sock *osk)
917 {
918 	nsk->sk_flags = osk->sk_flags;
919 }
920 
sock_set_flag(struct sock * sk,enum sock_flags flag)921 static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
922 {
923 	__set_bit(flag, &sk->sk_flags);
924 }
925 
sock_reset_flag(struct sock * sk,enum sock_flags flag)926 static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag)
927 {
928 	__clear_bit(flag, &sk->sk_flags);
929 }
930 
sock_valbool_flag(struct sock * sk,enum sock_flags bit,int valbool)931 static inline void sock_valbool_flag(struct sock *sk, enum sock_flags bit,
932 				     int valbool)
933 {
934 	if (valbool)
935 		sock_set_flag(sk, bit);
936 	else
937 		sock_reset_flag(sk, bit);
938 }
939 
sock_flag(const struct sock * sk,enum sock_flags flag)940 static inline bool sock_flag(const struct sock *sk, enum sock_flags flag)
941 {
942 	return test_bit(flag, &sk->sk_flags);
943 }
944 
945 #ifdef CONFIG_NET
946 DECLARE_STATIC_KEY_FALSE(memalloc_socks_key);
sk_memalloc_socks(void)947 static inline int sk_memalloc_socks(void)
948 {
949 	return static_branch_unlikely(&memalloc_socks_key);
950 }
951 
952 void __receive_sock(struct file *file);
953 #else
954 
sk_memalloc_socks(void)955 static inline int sk_memalloc_socks(void)
956 {
957 	return 0;
958 }
959 
__receive_sock(struct file * file)960 static inline void __receive_sock(struct file *file)
961 { }
962 #endif
963 
sk_gfp_mask(const struct sock * sk,gfp_t gfp_mask)964 static inline gfp_t sk_gfp_mask(const struct sock *sk, gfp_t gfp_mask)
965 {
966 	return gfp_mask | (sk->sk_allocation & __GFP_MEMALLOC);
967 }
968 
sk_acceptq_removed(struct sock * sk)969 static inline void sk_acceptq_removed(struct sock *sk)
970 {
971 	WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog - 1);
972 }
973 
sk_acceptq_added(struct sock * sk)974 static inline void sk_acceptq_added(struct sock *sk)
975 {
976 	WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog + 1);
977 }
978 
sk_acceptq_is_full(const struct sock * sk)979 static inline bool sk_acceptq_is_full(const struct sock *sk)
980 {
981 	return READ_ONCE(sk->sk_ack_backlog) > READ_ONCE(sk->sk_max_ack_backlog);
982 }
983 
984 /*
985  * Compute minimal free write space needed to queue new packets.
986  */
sk_stream_min_wspace(const struct sock * sk)987 static inline int sk_stream_min_wspace(const struct sock *sk)
988 {
989 	return READ_ONCE(sk->sk_wmem_queued) >> 1;
990 }
991 
sk_stream_wspace(const struct sock * sk)992 static inline int sk_stream_wspace(const struct sock *sk)
993 {
994 	return READ_ONCE(sk->sk_sndbuf) - READ_ONCE(sk->sk_wmem_queued);
995 }
996 
sk_wmem_queued_add(struct sock * sk,int val)997 static inline void sk_wmem_queued_add(struct sock *sk, int val)
998 {
999 	WRITE_ONCE(sk->sk_wmem_queued, sk->sk_wmem_queued + val);
1000 }
1001 
1002 void sk_stream_write_space(struct sock *sk);
1003 
1004 /* OOB backlog add */
__sk_add_backlog(struct sock * sk,struct sk_buff * skb)1005 static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
1006 {
1007 	/* dont let skb dst not refcounted, we are going to leave rcu lock */
1008 	skb_dst_force(skb);
1009 
1010 	if (!sk->sk_backlog.tail)
1011 		WRITE_ONCE(sk->sk_backlog.head, skb);
1012 	else
1013 		sk->sk_backlog.tail->next = skb;
1014 
1015 	WRITE_ONCE(sk->sk_backlog.tail, skb);
1016 	skb->next = NULL;
1017 }
1018 
1019 /*
1020  * Take into account size of receive queue and backlog queue
1021  * Do not take into account this skb truesize,
1022  * to allow even a single big packet to come.
1023  */
sk_rcvqueues_full(const struct sock * sk,unsigned int limit)1024 static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit)
1025 {
1026 	unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc);
1027 
1028 	return qsize > limit;
1029 }
1030 
1031 /* The per-socket spinlock must be held here. */
sk_add_backlog(struct sock * sk,struct sk_buff * skb,unsigned int limit)1032 static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb,
1033 					      unsigned int limit)
1034 {
1035 	if (sk_rcvqueues_full(sk, limit))
1036 		return -ENOBUFS;
1037 
1038 	/*
1039 	 * If the skb was allocated from pfmemalloc reserves, only
1040 	 * allow SOCK_MEMALLOC sockets to use it as this socket is
1041 	 * helping free memory
1042 	 */
1043 	if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC))
1044 		return -ENOMEM;
1045 
1046 	__sk_add_backlog(sk, skb);
1047 	sk->sk_backlog.len += skb->truesize;
1048 	return 0;
1049 }
1050 
1051 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb);
1052 
sk_backlog_rcv(struct sock * sk,struct sk_buff * skb)1053 static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
1054 {
1055 	if (sk_memalloc_socks() && skb_pfmemalloc(skb))
1056 		return __sk_backlog_rcv(sk, skb);
1057 
1058 	return sk->sk_backlog_rcv(sk, skb);
1059 }
1060 
sk_incoming_cpu_update(struct sock * sk)1061 static inline void sk_incoming_cpu_update(struct sock *sk)
1062 {
1063 	int cpu = raw_smp_processor_id();
1064 
1065 	if (unlikely(READ_ONCE(sk->sk_incoming_cpu) != cpu))
1066 		WRITE_ONCE(sk->sk_incoming_cpu, cpu);
1067 }
1068 
sock_rps_record_flow_hash(__u32 hash)1069 static inline void sock_rps_record_flow_hash(__u32 hash)
1070 {
1071 #ifdef CONFIG_RPS
1072 	struct rps_sock_flow_table *sock_flow_table;
1073 
1074 	rcu_read_lock();
1075 	sock_flow_table = rcu_dereference(rps_sock_flow_table);
1076 	rps_record_sock_flow(sock_flow_table, hash);
1077 	rcu_read_unlock();
1078 #endif
1079 }
1080 
sock_rps_record_flow(const struct sock * sk)1081 static inline void sock_rps_record_flow(const struct sock *sk)
1082 {
1083 #ifdef CONFIG_RPS
1084 	if (static_branch_unlikely(&rfs_needed)) {
1085 		/* Reading sk->sk_rxhash might incur an expensive cache line
1086 		 * miss.
1087 		 *
1088 		 * TCP_ESTABLISHED does cover almost all states where RFS
1089 		 * might be useful, and is cheaper [1] than testing :
1090 		 *	IPv4: inet_sk(sk)->inet_daddr
1091 		 * 	IPv6: ipv6_addr_any(&sk->sk_v6_daddr)
1092 		 * OR	an additional socket flag
1093 		 * [1] : sk_state and sk_prot are in the same cache line.
1094 		 */
1095 		if (sk->sk_state == TCP_ESTABLISHED)
1096 			sock_rps_record_flow_hash(sk->sk_rxhash);
1097 	}
1098 #endif
1099 }
1100 
sock_rps_save_rxhash(struct sock * sk,const struct sk_buff * skb)1101 static inline void sock_rps_save_rxhash(struct sock *sk,
1102 					const struct sk_buff *skb)
1103 {
1104 #ifdef CONFIG_RPS
1105 	if (unlikely(sk->sk_rxhash != skb->hash))
1106 		sk->sk_rxhash = skb->hash;
1107 #endif
1108 }
1109 
sock_rps_reset_rxhash(struct sock * sk)1110 static inline void sock_rps_reset_rxhash(struct sock *sk)
1111 {
1112 #ifdef CONFIG_RPS
1113 	sk->sk_rxhash = 0;
1114 #endif
1115 }
1116 
1117 #define sk_wait_event(__sk, __timeo, __condition, __wait)		\
1118 	({	int __rc;						\
1119 		release_sock(__sk);					\
1120 		__rc = __condition;					\
1121 		if (!__rc) {						\
1122 			*(__timeo) = wait_woken(__wait,			\
1123 						TASK_INTERRUPTIBLE,	\
1124 						*(__timeo));		\
1125 		}							\
1126 		sched_annotate_sleep();					\
1127 		lock_sock(__sk);					\
1128 		__rc = __condition;					\
1129 		__rc;							\
1130 	})
1131 
1132 int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
1133 int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
1134 void sk_stream_wait_close(struct sock *sk, long timeo_p);
1135 int sk_stream_error(struct sock *sk, int flags, int err);
1136 void sk_stream_kill_queues(struct sock *sk);
1137 void sk_set_memalloc(struct sock *sk);
1138 void sk_clear_memalloc(struct sock *sk);
1139 
1140 void __sk_flush_backlog(struct sock *sk);
1141 
sk_flush_backlog(struct sock * sk)1142 static inline bool sk_flush_backlog(struct sock *sk)
1143 {
1144 	if (unlikely(READ_ONCE(sk->sk_backlog.tail))) {
1145 		__sk_flush_backlog(sk);
1146 		return true;
1147 	}
1148 	return false;
1149 }
1150 
1151 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb);
1152 
1153 struct request_sock_ops;
1154 struct timewait_sock_ops;
1155 struct inet_hashinfo;
1156 struct raw_hashinfo;
1157 struct smc_hashinfo;
1158 struct module;
1159 
1160 /*
1161  * caches using SLAB_TYPESAFE_BY_RCU should let .next pointer from nulls nodes
1162  * un-modified. Special care is taken when initializing object to zero.
1163  */
sk_prot_clear_nulls(struct sock * sk,int size)1164 static inline void sk_prot_clear_nulls(struct sock *sk, int size)
1165 {
1166 	if (offsetof(struct sock, sk_node.next) != 0)
1167 		memset(sk, 0, offsetof(struct sock, sk_node.next));
1168 	memset(&sk->sk_node.pprev, 0,
1169 	       size - offsetof(struct sock, sk_node.pprev));
1170 }
1171 
1172 /* Networking protocol blocks we attach to sockets.
1173  * socket layer -> transport layer interface
1174  */
1175 struct proto {
1176 	void			(*close)(struct sock *sk,
1177 					long timeout);
1178 	int			(*pre_connect)(struct sock *sk,
1179 					struct sockaddr *uaddr,
1180 					int addr_len);
1181 	int			(*connect)(struct sock *sk,
1182 					struct sockaddr *uaddr,
1183 					int addr_len);
1184 	int			(*disconnect)(struct sock *sk, int flags);
1185 
1186 	struct sock *		(*accept)(struct sock *sk, int flags, int *err,
1187 					  bool kern);
1188 
1189 	int			(*ioctl)(struct sock *sk, int cmd,
1190 					 unsigned long arg);
1191 	int			(*init)(struct sock *sk);
1192 	void			(*destroy)(struct sock *sk);
1193 	void			(*shutdown)(struct sock *sk, int how);
1194 	int			(*setsockopt)(struct sock *sk, int level,
1195 					int optname, sockptr_t optval,
1196 					unsigned int optlen);
1197 	int			(*getsockopt)(struct sock *sk, int level,
1198 					int optname, char __user *optval,
1199 					int __user *option);
1200 	void			(*keepalive)(struct sock *sk, int valbool);
1201 #ifdef CONFIG_COMPAT
1202 	int			(*compat_ioctl)(struct sock *sk,
1203 					unsigned int cmd, unsigned long arg);
1204 #endif
1205 	int			(*sendmsg)(struct sock *sk, struct msghdr *msg,
1206 					   size_t len);
1207 	int			(*recvmsg)(struct sock *sk, struct msghdr *msg,
1208 					   size_t len, int noblock, int flags,
1209 					   int *addr_len);
1210 	int			(*sendpage)(struct sock *sk, struct page *page,
1211 					int offset, size_t size, int flags);
1212 	int			(*bind)(struct sock *sk,
1213 					struct sockaddr *addr, int addr_len);
1214 	int			(*bind_add)(struct sock *sk,
1215 					struct sockaddr *addr, int addr_len);
1216 
1217 	int			(*backlog_rcv) (struct sock *sk,
1218 						struct sk_buff *skb);
1219 
1220 	void		(*release_cb)(struct sock *sk);
1221 
1222 	/* Keeping track of sk's, looking them up, and port selection methods. */
1223 	int			(*hash)(struct sock *sk);
1224 	void			(*unhash)(struct sock *sk);
1225 	void			(*rehash)(struct sock *sk);
1226 	int			(*get_port)(struct sock *sk, unsigned short snum);
1227 
1228 	/* Keeping track of sockets in use */
1229 #ifdef CONFIG_PROC_FS
1230 	unsigned int		inuse_idx;
1231 #endif
1232 
1233 	bool			(*stream_memory_free)(const struct sock *sk, int wake);
1234 	bool			(*stream_memory_read)(const struct sock *sk);
1235 	/* Memory pressure */
1236 	void			(*enter_memory_pressure)(struct sock *sk);
1237 	void			(*leave_memory_pressure)(struct sock *sk);
1238 	atomic_long_t		*memory_allocated;	/* Current allocated memory. */
1239 	struct percpu_counter	*sockets_allocated;	/* Current number of sockets. */
1240 	/*
1241 	 * Pressure flag: try to collapse.
1242 	 * Technical note: it is used by multiple contexts non atomically.
1243 	 * All the __sk_mem_schedule() is of this nature: accounting
1244 	 * is strict, actions are advisory and have some latency.
1245 	 */
1246 	unsigned long		*memory_pressure;
1247 	long			*sysctl_mem;
1248 
1249 	int			*sysctl_wmem;
1250 	int			*sysctl_rmem;
1251 	u32			sysctl_wmem_offset;
1252 	u32			sysctl_rmem_offset;
1253 
1254 	int			max_header;
1255 	bool			no_autobind;
1256 
1257 	struct kmem_cache	*slab;
1258 	unsigned int		obj_size;
1259 	slab_flags_t		slab_flags;
1260 	unsigned int		useroffset;	/* Usercopy region offset */
1261 	unsigned int		usersize;	/* Usercopy region size */
1262 
1263 	struct percpu_counter	*orphan_count;
1264 
1265 	struct request_sock_ops	*rsk_prot;
1266 	struct timewait_sock_ops *twsk_prot;
1267 
1268 	union {
1269 		struct inet_hashinfo	*hashinfo;
1270 		struct udp_table	*udp_table;
1271 		struct raw_hashinfo	*raw_hash;
1272 		struct smc_hashinfo	*smc_hash;
1273 	} h;
1274 
1275 	struct module		*owner;
1276 
1277 	char			name[32];
1278 
1279 	struct list_head	node;
1280 #ifdef SOCK_REFCNT_DEBUG
1281 	atomic_t		socks;
1282 #endif
1283 	int			(*diag_destroy)(struct sock *sk, int err);
1284 } __randomize_layout;
1285 
1286 int proto_register(struct proto *prot, int alloc_slab);
1287 void proto_unregister(struct proto *prot);
1288 int sock_load_diag_module(int family, int protocol);
1289 
1290 #ifdef SOCK_REFCNT_DEBUG
sk_refcnt_debug_inc(struct sock * sk)1291 static inline void sk_refcnt_debug_inc(struct sock *sk)
1292 {
1293 	atomic_inc(&sk->sk_prot->socks);
1294 }
1295 
sk_refcnt_debug_dec(struct sock * sk)1296 static inline void sk_refcnt_debug_dec(struct sock *sk)
1297 {
1298 	atomic_dec(&sk->sk_prot->socks);
1299 	printk(KERN_DEBUG "%s socket %p released, %d are still alive\n",
1300 	       sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks));
1301 }
1302 
sk_refcnt_debug_release(const struct sock * sk)1303 static inline void sk_refcnt_debug_release(const struct sock *sk)
1304 {
1305 	if (refcount_read(&sk->sk_refcnt) != 1)
1306 		printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n",
1307 		       sk->sk_prot->name, sk, refcount_read(&sk->sk_refcnt));
1308 }
1309 #else /* SOCK_REFCNT_DEBUG */
1310 #define sk_refcnt_debug_inc(sk) do { } while (0)
1311 #define sk_refcnt_debug_dec(sk) do { } while (0)
1312 #define sk_refcnt_debug_release(sk) do { } while (0)
1313 #endif /* SOCK_REFCNT_DEBUG */
1314 
__sk_stream_memory_free(const struct sock * sk,int wake)1315 static inline bool __sk_stream_memory_free(const struct sock *sk, int wake)
1316 {
1317 	if (READ_ONCE(sk->sk_wmem_queued) >= READ_ONCE(sk->sk_sndbuf))
1318 		return false;
1319 
1320 	return sk->sk_prot->stream_memory_free ?
1321 		sk->sk_prot->stream_memory_free(sk, wake) : true;
1322 }
1323 
sk_stream_memory_free(const struct sock * sk)1324 static inline bool sk_stream_memory_free(const struct sock *sk)
1325 {
1326 	return __sk_stream_memory_free(sk, 0);
1327 }
1328 
__sk_stream_is_writeable(const struct sock * sk,int wake)1329 static inline bool __sk_stream_is_writeable(const struct sock *sk, int wake)
1330 {
1331 	return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) &&
1332 	       __sk_stream_memory_free(sk, wake);
1333 }
1334 
sk_stream_is_writeable(const struct sock * sk)1335 static inline bool sk_stream_is_writeable(const struct sock *sk)
1336 {
1337 	return __sk_stream_is_writeable(sk, 0);
1338 }
1339 
sk_under_cgroup_hierarchy(struct sock * sk,struct cgroup * ancestor)1340 static inline int sk_under_cgroup_hierarchy(struct sock *sk,
1341 					    struct cgroup *ancestor)
1342 {
1343 #ifdef CONFIG_SOCK_CGROUP_DATA
1344 	return cgroup_is_descendant(sock_cgroup_ptr(&sk->sk_cgrp_data),
1345 				    ancestor);
1346 #else
1347 	return -ENOTSUPP;
1348 #endif
1349 }
1350 
sk_has_memory_pressure(const struct sock * sk)1351 static inline bool sk_has_memory_pressure(const struct sock *sk)
1352 {
1353 	return sk->sk_prot->memory_pressure != NULL;
1354 }
1355 
sk_under_memory_pressure(const struct sock * sk)1356 static inline bool sk_under_memory_pressure(const struct sock *sk)
1357 {
1358 	if (!sk->sk_prot->memory_pressure)
1359 		return false;
1360 
1361 	if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
1362 	    mem_cgroup_under_socket_pressure(sk->sk_memcg))
1363 		return true;
1364 
1365 	return !!*sk->sk_prot->memory_pressure;
1366 }
1367 
1368 static inline long
sk_memory_allocated(const struct sock * sk)1369 sk_memory_allocated(const struct sock *sk)
1370 {
1371 	return atomic_long_read(sk->sk_prot->memory_allocated);
1372 }
1373 
1374 static inline long
sk_memory_allocated_add(struct sock * sk,int amt)1375 sk_memory_allocated_add(struct sock *sk, int amt)
1376 {
1377 	return atomic_long_add_return(amt, sk->sk_prot->memory_allocated);
1378 }
1379 
1380 static inline void
sk_memory_allocated_sub(struct sock * sk,int amt)1381 sk_memory_allocated_sub(struct sock *sk, int amt)
1382 {
1383 	atomic_long_sub(amt, sk->sk_prot->memory_allocated);
1384 }
1385 
sk_sockets_allocated_dec(struct sock * sk)1386 static inline void sk_sockets_allocated_dec(struct sock *sk)
1387 {
1388 	percpu_counter_dec(sk->sk_prot->sockets_allocated);
1389 }
1390 
sk_sockets_allocated_inc(struct sock * sk)1391 static inline void sk_sockets_allocated_inc(struct sock *sk)
1392 {
1393 	percpu_counter_inc(sk->sk_prot->sockets_allocated);
1394 }
1395 
1396 static inline u64
sk_sockets_allocated_read_positive(struct sock * sk)1397 sk_sockets_allocated_read_positive(struct sock *sk)
1398 {
1399 	return percpu_counter_read_positive(sk->sk_prot->sockets_allocated);
1400 }
1401 
1402 static inline int
proto_sockets_allocated_sum_positive(struct proto * prot)1403 proto_sockets_allocated_sum_positive(struct proto *prot)
1404 {
1405 	return percpu_counter_sum_positive(prot->sockets_allocated);
1406 }
1407 
1408 static inline long
proto_memory_allocated(struct proto * prot)1409 proto_memory_allocated(struct proto *prot)
1410 {
1411 	return atomic_long_read(prot->memory_allocated);
1412 }
1413 
1414 static inline bool
proto_memory_pressure(struct proto * prot)1415 proto_memory_pressure(struct proto *prot)
1416 {
1417 	if (!prot->memory_pressure)
1418 		return false;
1419 	return !!*prot->memory_pressure;
1420 }
1421 
1422 
1423 #ifdef CONFIG_PROC_FS
1424 /* Called with local bh disabled */
1425 void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc);
1426 int sock_prot_inuse_get(struct net *net, struct proto *proto);
1427 int sock_inuse_get(struct net *net);
1428 #else
sock_prot_inuse_add(struct net * net,struct proto * prot,int inc)1429 static inline void sock_prot_inuse_add(struct net *net, struct proto *prot,
1430 		int inc)
1431 {
1432 }
1433 #endif
1434 
1435 
1436 /* With per-bucket locks this operation is not-atomic, so that
1437  * this version is not worse.
1438  */
__sk_prot_rehash(struct sock * sk)1439 static inline int __sk_prot_rehash(struct sock *sk)
1440 {
1441 	sk->sk_prot->unhash(sk);
1442 	return sk->sk_prot->hash(sk);
1443 }
1444 
1445 /* About 10 seconds */
1446 #define SOCK_DESTROY_TIME (10*HZ)
1447 
1448 /* Sockets 0-1023 can't be bound to unless you are superuser */
1449 #define PROT_SOCK	1024
1450 
1451 #define SHUTDOWN_MASK	3
1452 #define RCV_SHUTDOWN	1
1453 #define SEND_SHUTDOWN	2
1454 
1455 #define SOCK_SNDBUF_LOCK	1
1456 #define SOCK_RCVBUF_LOCK	2
1457 #define SOCK_BINDADDR_LOCK	4
1458 #define SOCK_BINDPORT_LOCK	8
1459 
1460 struct socket_alloc {
1461 	struct socket socket;
1462 	struct inode vfs_inode;
1463 };
1464 
SOCKET_I(struct inode * inode)1465 static inline struct socket *SOCKET_I(struct inode *inode)
1466 {
1467 	return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
1468 }
1469 
SOCK_INODE(struct socket * socket)1470 static inline struct inode *SOCK_INODE(struct socket *socket)
1471 {
1472 	return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
1473 }
1474 
1475 /*
1476  * Functions for memory accounting
1477  */
1478 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind);
1479 int __sk_mem_schedule(struct sock *sk, int size, int kind);
1480 void __sk_mem_reduce_allocated(struct sock *sk, int amount);
1481 void __sk_mem_reclaim(struct sock *sk, int amount);
1482 
1483 /* We used to have PAGE_SIZE here, but systems with 64KB pages
1484  * do not necessarily have 16x time more memory than 4KB ones.
1485  */
1486 #define SK_MEM_QUANTUM 4096
1487 #define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM)
1488 #define SK_MEM_SEND	0
1489 #define SK_MEM_RECV	1
1490 
1491 /* sysctl_mem values are in pages, we convert them in SK_MEM_QUANTUM units */
sk_prot_mem_limits(const struct sock * sk,int index)1492 static inline long sk_prot_mem_limits(const struct sock *sk, int index)
1493 {
1494 	long val = READ_ONCE(sk->sk_prot->sysctl_mem[index]);
1495 
1496 #if PAGE_SIZE > SK_MEM_QUANTUM
1497 	val <<= PAGE_SHIFT - SK_MEM_QUANTUM_SHIFT;
1498 #elif PAGE_SIZE < SK_MEM_QUANTUM
1499 	val >>= SK_MEM_QUANTUM_SHIFT - PAGE_SHIFT;
1500 #endif
1501 	return val;
1502 }
1503 
sk_mem_pages(int amt)1504 static inline int sk_mem_pages(int amt)
1505 {
1506 	return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT;
1507 }
1508 
sk_has_account(struct sock * sk)1509 static inline bool sk_has_account(struct sock *sk)
1510 {
1511 	/* return true if protocol supports memory accounting */
1512 	return !!sk->sk_prot->memory_allocated;
1513 }
1514 
sk_wmem_schedule(struct sock * sk,int size)1515 static inline bool sk_wmem_schedule(struct sock *sk, int size)
1516 {
1517 	int delta;
1518 
1519 	if (!sk_has_account(sk))
1520 		return true;
1521 	delta = size - sk->sk_forward_alloc;
1522 	return delta <= 0 || __sk_mem_schedule(sk, delta, SK_MEM_SEND);
1523 }
1524 
1525 static inline bool
sk_rmem_schedule(struct sock * sk,struct sk_buff * skb,int size)1526 sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size)
1527 {
1528 	int delta;
1529 
1530 	if (!sk_has_account(sk))
1531 		return true;
1532 	delta = size - sk->sk_forward_alloc;
1533 	return delta <= 0 || __sk_mem_schedule(sk, delta, SK_MEM_RECV) ||
1534 		skb_pfmemalloc(skb);
1535 }
1536 
sk_mem_reclaim(struct sock * sk)1537 static inline void sk_mem_reclaim(struct sock *sk)
1538 {
1539 	if (!sk_has_account(sk))
1540 		return;
1541 	if (sk->sk_forward_alloc >= SK_MEM_QUANTUM)
1542 		__sk_mem_reclaim(sk, sk->sk_forward_alloc);
1543 }
1544 
sk_mem_reclaim_partial(struct sock * sk)1545 static inline void sk_mem_reclaim_partial(struct sock *sk)
1546 {
1547 	if (!sk_has_account(sk))
1548 		return;
1549 	if (sk->sk_forward_alloc > SK_MEM_QUANTUM)
1550 		__sk_mem_reclaim(sk, sk->sk_forward_alloc - 1);
1551 }
1552 
sk_mem_charge(struct sock * sk,int size)1553 static inline void sk_mem_charge(struct sock *sk, int size)
1554 {
1555 	if (!sk_has_account(sk))
1556 		return;
1557 	sk->sk_forward_alloc -= size;
1558 }
1559 
sk_mem_uncharge(struct sock * sk,int size)1560 static inline void sk_mem_uncharge(struct sock *sk, int size)
1561 {
1562 	if (!sk_has_account(sk))
1563 		return;
1564 	sk->sk_forward_alloc += size;
1565 
1566 	/* Avoid a possible overflow.
1567 	 * TCP send queues can make this happen, if sk_mem_reclaim()
1568 	 * is not called and more than 2 GBytes are released at once.
1569 	 *
1570 	 * If we reach 2 MBytes, reclaim 1 MBytes right now, there is
1571 	 * no need to hold that much forward allocation anyway.
1572 	 */
1573 	if (unlikely(sk->sk_forward_alloc >= 1 << 21))
1574 		__sk_mem_reclaim(sk, 1 << 20);
1575 }
1576 
1577 DECLARE_STATIC_KEY_FALSE(tcp_tx_skb_cache_key);
sk_wmem_free_skb(struct sock * sk,struct sk_buff * skb)1578 static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb)
1579 {
1580 	sk_wmem_queued_add(sk, -skb->truesize);
1581 	sk_mem_uncharge(sk, skb->truesize);
1582 	if (static_branch_unlikely(&tcp_tx_skb_cache_key) &&
1583 	    !sk->sk_tx_skb_cache && !skb_cloned(skb)) {
1584 		skb_ext_reset(skb);
1585 		skb_zcopy_clear(skb, true);
1586 		sk->sk_tx_skb_cache = skb;
1587 		return;
1588 	}
1589 	__kfree_skb(skb);
1590 }
1591 
sock_release_ownership(struct sock * sk)1592 static inline void sock_release_ownership(struct sock *sk)
1593 {
1594 	if (sk->sk_lock.owned) {
1595 		sk->sk_lock.owned = 0;
1596 
1597 		/* The sk_lock has mutex_unlock() semantics: */
1598 		mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
1599 	}
1600 }
1601 
1602 /*
1603  * Macro so as to not evaluate some arguments when
1604  * lockdep is not enabled.
1605  *
1606  * Mark both the sk_lock and the sk_lock.slock as a
1607  * per-address-family lock class.
1608  */
1609 #define sock_lock_init_class_and_name(sk, sname, skey, name, key)	\
1610 do {									\
1611 	sk->sk_lock.owned = 0;						\
1612 	init_waitqueue_head(&sk->sk_lock.wq);				\
1613 	spin_lock_init(&(sk)->sk_lock.slock);				\
1614 	debug_check_no_locks_freed((void *)&(sk)->sk_lock,		\
1615 			sizeof((sk)->sk_lock));				\
1616 	lockdep_set_class_and_name(&(sk)->sk_lock.slock,		\
1617 				(skey), (sname));				\
1618 	lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0);	\
1619 } while (0)
1620 
1621 #ifdef CONFIG_LOCKDEP
lockdep_sock_is_held(const struct sock * sk)1622 static inline bool lockdep_sock_is_held(const struct sock *sk)
1623 {
1624 	return lockdep_is_held(&sk->sk_lock) ||
1625 	       lockdep_is_held(&sk->sk_lock.slock);
1626 }
1627 #endif
1628 
1629 void lock_sock_nested(struct sock *sk, int subclass);
1630 
lock_sock(struct sock * sk)1631 static inline void lock_sock(struct sock *sk)
1632 {
1633 	lock_sock_nested(sk, 0);
1634 }
1635 
1636 void __release_sock(struct sock *sk);
1637 void release_sock(struct sock *sk);
1638 
1639 /* BH context may only use the following locking interface. */
1640 #define bh_lock_sock(__sk)	spin_lock(&((__sk)->sk_lock.slock))
1641 #define bh_lock_sock_nested(__sk) \
1642 				spin_lock_nested(&((__sk)->sk_lock.slock), \
1643 				SINGLE_DEPTH_NESTING)
1644 #define bh_unlock_sock(__sk)	spin_unlock(&((__sk)->sk_lock.slock))
1645 
1646 bool lock_sock_fast(struct sock *sk);
1647 /**
1648  * unlock_sock_fast - complement of lock_sock_fast
1649  * @sk: socket
1650  * @slow: slow mode
1651  *
1652  * fast unlock socket for user context.
1653  * If slow mode is on, we call regular release_sock()
1654  */
unlock_sock_fast(struct sock * sk,bool slow)1655 static inline void unlock_sock_fast(struct sock *sk, bool slow)
1656 {
1657 	if (slow)
1658 		release_sock(sk);
1659 	else
1660 		spin_unlock_bh(&sk->sk_lock.slock);
1661 }
1662 
1663 /* Used by processes to "lock" a socket state, so that
1664  * interrupts and bottom half handlers won't change it
1665  * from under us. It essentially blocks any incoming
1666  * packets, so that we won't get any new data or any
1667  * packets that change the state of the socket.
1668  *
1669  * While locked, BH processing will add new packets to
1670  * the backlog queue.  This queue is processed by the
1671  * owner of the socket lock right before it is released.
1672  *
1673  * Since ~2.3.5 it is also exclusive sleep lock serializing
1674  * accesses from user process context.
1675  */
1676 
sock_owned_by_me(const struct sock * sk)1677 static inline void sock_owned_by_me(const struct sock *sk)
1678 {
1679 #ifdef CONFIG_LOCKDEP
1680 	WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks);
1681 #endif
1682 }
1683 
sock_owned_by_user(const struct sock * sk)1684 static inline bool sock_owned_by_user(const struct sock *sk)
1685 {
1686 	sock_owned_by_me(sk);
1687 	return sk->sk_lock.owned;
1688 }
1689 
sock_owned_by_user_nocheck(const struct sock * sk)1690 static inline bool sock_owned_by_user_nocheck(const struct sock *sk)
1691 {
1692 	return sk->sk_lock.owned;
1693 }
1694 
1695 /* no reclassification while locks are held */
sock_allow_reclassification(const struct sock * csk)1696 static inline bool sock_allow_reclassification(const struct sock *csk)
1697 {
1698 	struct sock *sk = (struct sock *)csk;
1699 
1700 	return !sk->sk_lock.owned && !spin_is_locked(&sk->sk_lock.slock);
1701 }
1702 
1703 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1704 		      struct proto *prot, int kern);
1705 void sk_free(struct sock *sk);
1706 void sk_destruct(struct sock *sk);
1707 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority);
1708 void sk_free_unlock_clone(struct sock *sk);
1709 
1710 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1711 			     gfp_t priority);
1712 void __sock_wfree(struct sk_buff *skb);
1713 void sock_wfree(struct sk_buff *skb);
1714 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
1715 			     gfp_t priority);
1716 void skb_orphan_partial(struct sk_buff *skb);
1717 void sock_rfree(struct sk_buff *skb);
1718 void sock_efree(struct sk_buff *skb);
1719 #ifdef CONFIG_INET
1720 void sock_edemux(struct sk_buff *skb);
1721 void sock_pfree(struct sk_buff *skb);
1722 #else
1723 #define sock_edemux sock_efree
1724 #endif
1725 
1726 int sock_setsockopt(struct socket *sock, int level, int op,
1727 		    sockptr_t optval, unsigned int optlen);
1728 
1729 int sock_getsockopt(struct socket *sock, int level, int op,
1730 		    char __user *optval, int __user *optlen);
1731 int sock_gettstamp(struct socket *sock, void __user *userstamp,
1732 		   bool timeval, bool time32);
1733 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1734 				    int noblock, int *errcode);
1735 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1736 				     unsigned long data_len, int noblock,
1737 				     int *errcode, int max_page_order);
1738 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority);
1739 void sock_kfree_s(struct sock *sk, void *mem, int size);
1740 void sock_kzfree_s(struct sock *sk, void *mem, int size);
1741 void sk_send_sigurg(struct sock *sk);
1742 
1743 struct sockcm_cookie {
1744 	u64 transmit_time;
1745 	u32 mark;
1746 	u16 tsflags;
1747 };
1748 
sockcm_init(struct sockcm_cookie * sockc,const struct sock * sk)1749 static inline void sockcm_init(struct sockcm_cookie *sockc,
1750 			       const struct sock *sk)
1751 {
1752 	*sockc = (struct sockcm_cookie) { .tsflags = sk->sk_tsflags };
1753 }
1754 
1755 int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg,
1756 		     struct sockcm_cookie *sockc);
1757 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
1758 		   struct sockcm_cookie *sockc);
1759 
1760 /*
1761  * Functions to fill in entries in struct proto_ops when a protocol
1762  * does not implement a particular function.
1763  */
1764 int sock_no_bind(struct socket *, struct sockaddr *, int);
1765 int sock_no_connect(struct socket *, struct sockaddr *, int, int);
1766 int sock_no_socketpair(struct socket *, struct socket *);
1767 int sock_no_accept(struct socket *, struct socket *, int, bool);
1768 int sock_no_getname(struct socket *, struct sockaddr *, int);
1769 int sock_no_ioctl(struct socket *, unsigned int, unsigned long);
1770 int sock_no_listen(struct socket *, int);
1771 int sock_no_shutdown(struct socket *, int);
1772 int sock_no_sendmsg(struct socket *, struct msghdr *, size_t);
1773 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len);
1774 int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int);
1775 int sock_no_mmap(struct file *file, struct socket *sock,
1776 		 struct vm_area_struct *vma);
1777 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset,
1778 			 size_t size, int flags);
1779 ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
1780 				int offset, size_t size, int flags);
1781 
1782 /*
1783  * Functions to fill in entries in struct proto_ops when a protocol
1784  * uses the inet style.
1785  */
1786 int sock_common_getsockopt(struct socket *sock, int level, int optname,
1787 				  char __user *optval, int __user *optlen);
1788 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1789 			int flags);
1790 int sock_common_setsockopt(struct socket *sock, int level, int optname,
1791 			   sockptr_t optval, unsigned int optlen);
1792 
1793 void sk_common_release(struct sock *sk);
1794 
1795 /*
1796  *	Default socket callbacks and setup code
1797  */
1798 
1799 /* Initialise core socket variables */
1800 void sock_init_data(struct socket *sock, struct sock *sk);
1801 
1802 /*
1803  * Socket reference counting postulates.
1804  *
1805  * * Each user of socket SHOULD hold a reference count.
1806  * * Each access point to socket (an hash table bucket, reference from a list,
1807  *   running timer, skb in flight MUST hold a reference count.
1808  * * When reference count hits 0, it means it will never increase back.
1809  * * When reference count hits 0, it means that no references from
1810  *   outside exist to this socket and current process on current CPU
1811  *   is last user and may/should destroy this socket.
1812  * * sk_free is called from any context: process, BH, IRQ. When
1813  *   it is called, socket has no references from outside -> sk_free
1814  *   may release descendant resources allocated by the socket, but
1815  *   to the time when it is called, socket is NOT referenced by any
1816  *   hash tables, lists etc.
1817  * * Packets, delivered from outside (from network or from another process)
1818  *   and enqueued on receive/error queues SHOULD NOT grab reference count,
1819  *   when they sit in queue. Otherwise, packets will leak to hole, when
1820  *   socket is looked up by one cpu and unhasing is made by another CPU.
1821  *   It is true for udp/raw, netlink (leak to receive and error queues), tcp
1822  *   (leak to backlog). Packet socket does all the processing inside
1823  *   BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
1824  *   use separate SMP lock, so that they are prone too.
1825  */
1826 
1827 /* Ungrab socket and destroy it, if it was the last reference. */
sock_put(struct sock * sk)1828 static inline void sock_put(struct sock *sk)
1829 {
1830 	if (refcount_dec_and_test(&sk->sk_refcnt))
1831 		sk_free(sk);
1832 }
1833 /* Generic version of sock_put(), dealing with all sockets
1834  * (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...)
1835  */
1836 void sock_gen_put(struct sock *sk);
1837 
1838 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested,
1839 		     unsigned int trim_cap, bool refcounted);
sk_receive_skb(struct sock * sk,struct sk_buff * skb,const int nested)1840 static inline int sk_receive_skb(struct sock *sk, struct sk_buff *skb,
1841 				 const int nested)
1842 {
1843 	return __sk_receive_skb(sk, skb, nested, 1, true);
1844 }
1845 
sk_tx_queue_set(struct sock * sk,int tx_queue)1846 static inline void sk_tx_queue_set(struct sock *sk, int tx_queue)
1847 {
1848 	/* sk_tx_queue_mapping accept only upto a 16-bit value */
1849 	if (WARN_ON_ONCE((unsigned short)tx_queue >= USHRT_MAX))
1850 		return;
1851 	sk->sk_tx_queue_mapping = tx_queue;
1852 }
1853 
1854 #define NO_QUEUE_MAPPING	USHRT_MAX
1855 
sk_tx_queue_clear(struct sock * sk)1856 static inline void sk_tx_queue_clear(struct sock *sk)
1857 {
1858 	sk->sk_tx_queue_mapping = NO_QUEUE_MAPPING;
1859 }
1860 
sk_tx_queue_get(const struct sock * sk)1861 static inline int sk_tx_queue_get(const struct sock *sk)
1862 {
1863 	if (sk && sk->sk_tx_queue_mapping != NO_QUEUE_MAPPING)
1864 		return sk->sk_tx_queue_mapping;
1865 
1866 	return -1;
1867 }
1868 
sk_rx_queue_set(struct sock * sk,const struct sk_buff * skb)1869 static inline void sk_rx_queue_set(struct sock *sk, const struct sk_buff *skb)
1870 {
1871 #ifdef CONFIG_XPS
1872 	if (skb_rx_queue_recorded(skb)) {
1873 		u16 rx_queue = skb_get_rx_queue(skb);
1874 
1875 		if (WARN_ON_ONCE(rx_queue == NO_QUEUE_MAPPING))
1876 			return;
1877 
1878 		sk->sk_rx_queue_mapping = rx_queue;
1879 	}
1880 #endif
1881 }
1882 
sk_rx_queue_clear(struct sock * sk)1883 static inline void sk_rx_queue_clear(struct sock *sk)
1884 {
1885 #ifdef CONFIG_XPS
1886 	sk->sk_rx_queue_mapping = NO_QUEUE_MAPPING;
1887 #endif
1888 }
1889 
1890 #ifdef CONFIG_XPS
sk_rx_queue_get(const struct sock * sk)1891 static inline int sk_rx_queue_get(const struct sock *sk)
1892 {
1893 	if (sk && sk->sk_rx_queue_mapping != NO_QUEUE_MAPPING)
1894 		return sk->sk_rx_queue_mapping;
1895 
1896 	return -1;
1897 }
1898 #endif
1899 
sk_set_socket(struct sock * sk,struct socket * sock)1900 static inline void sk_set_socket(struct sock *sk, struct socket *sock)
1901 {
1902 	sk->sk_socket = sock;
1903 }
1904 
sk_sleep(struct sock * sk)1905 static inline wait_queue_head_t *sk_sleep(struct sock *sk)
1906 {
1907 	BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0);
1908 	return &rcu_dereference_raw(sk->sk_wq)->wait;
1909 }
1910 /* Detach socket from process context.
1911  * Announce socket dead, detach it from wait queue and inode.
1912  * Note that parent inode held reference count on this struct sock,
1913  * we do not release it in this function, because protocol
1914  * probably wants some additional cleanups or even continuing
1915  * to work with this socket (TCP).
1916  */
sock_orphan(struct sock * sk)1917 static inline void sock_orphan(struct sock *sk)
1918 {
1919 	write_lock_bh(&sk->sk_callback_lock);
1920 	sock_set_flag(sk, SOCK_DEAD);
1921 	sk_set_socket(sk, NULL);
1922 	sk->sk_wq  = NULL;
1923 	write_unlock_bh(&sk->sk_callback_lock);
1924 }
1925 
sock_graft(struct sock * sk,struct socket * parent)1926 static inline void sock_graft(struct sock *sk, struct socket *parent)
1927 {
1928 	WARN_ON(parent->sk);
1929 	write_lock_bh(&sk->sk_callback_lock);
1930 	rcu_assign_pointer(sk->sk_wq, &parent->wq);
1931 	parent->sk = sk;
1932 	sk_set_socket(sk, parent);
1933 	sk->sk_uid = SOCK_INODE(parent)->i_uid;
1934 	security_sock_graft(sk, parent);
1935 	write_unlock_bh(&sk->sk_callback_lock);
1936 }
1937 
1938 kuid_t sock_i_uid(struct sock *sk);
1939 unsigned long sock_i_ino(struct sock *sk);
1940 
sock_net_uid(const struct net * net,const struct sock * sk)1941 static inline kuid_t sock_net_uid(const struct net *net, const struct sock *sk)
1942 {
1943 	return sk ? sk->sk_uid : make_kuid(net->user_ns, 0);
1944 }
1945 
net_tx_rndhash(void)1946 static inline u32 net_tx_rndhash(void)
1947 {
1948 	u32 v = prandom_u32();
1949 
1950 	return v ?: 1;
1951 }
1952 
sk_set_txhash(struct sock * sk)1953 static inline void sk_set_txhash(struct sock *sk)
1954 {
1955 	/* This pairs with READ_ONCE() in skb_set_hash_from_sk() */
1956 	WRITE_ONCE(sk->sk_txhash, net_tx_rndhash());
1957 }
1958 
sk_rethink_txhash(struct sock * sk)1959 static inline bool sk_rethink_txhash(struct sock *sk)
1960 {
1961 	if (sk->sk_txhash) {
1962 		sk_set_txhash(sk);
1963 		return true;
1964 	}
1965 	return false;
1966 }
1967 
1968 static inline struct dst_entry *
__sk_dst_get(struct sock * sk)1969 __sk_dst_get(struct sock *sk)
1970 {
1971 	return rcu_dereference_check(sk->sk_dst_cache,
1972 				     lockdep_sock_is_held(sk));
1973 }
1974 
1975 static inline struct dst_entry *
sk_dst_get(struct sock * sk)1976 sk_dst_get(struct sock *sk)
1977 {
1978 	struct dst_entry *dst;
1979 
1980 	rcu_read_lock();
1981 	dst = rcu_dereference(sk->sk_dst_cache);
1982 	if (dst && !atomic_inc_not_zero(&dst->__refcnt))
1983 		dst = NULL;
1984 	rcu_read_unlock();
1985 	return dst;
1986 }
1987 
__dst_negative_advice(struct sock * sk)1988 static inline void __dst_negative_advice(struct sock *sk)
1989 {
1990 	struct dst_entry *ndst, *dst = __sk_dst_get(sk);
1991 
1992 	if (dst && dst->ops->negative_advice) {
1993 		ndst = dst->ops->negative_advice(dst);
1994 
1995 		if (ndst != dst) {
1996 			rcu_assign_pointer(sk->sk_dst_cache, ndst);
1997 			sk_tx_queue_clear(sk);
1998 			sk->sk_dst_pending_confirm = 0;
1999 		}
2000 	}
2001 }
2002 
dst_negative_advice(struct sock * sk)2003 static inline void dst_negative_advice(struct sock *sk)
2004 {
2005 	sk_rethink_txhash(sk);
2006 	__dst_negative_advice(sk);
2007 }
2008 
2009 static inline void
__sk_dst_set(struct sock * sk,struct dst_entry * dst)2010 __sk_dst_set(struct sock *sk, struct dst_entry *dst)
2011 {
2012 	struct dst_entry *old_dst;
2013 
2014 	sk_tx_queue_clear(sk);
2015 	sk->sk_dst_pending_confirm = 0;
2016 	old_dst = rcu_dereference_protected(sk->sk_dst_cache,
2017 					    lockdep_sock_is_held(sk));
2018 	rcu_assign_pointer(sk->sk_dst_cache, dst);
2019 	dst_release(old_dst);
2020 }
2021 
2022 static inline void
sk_dst_set(struct sock * sk,struct dst_entry * dst)2023 sk_dst_set(struct sock *sk, struct dst_entry *dst)
2024 {
2025 	struct dst_entry *old_dst;
2026 
2027 	sk_tx_queue_clear(sk);
2028 	sk->sk_dst_pending_confirm = 0;
2029 	old_dst = xchg((__force struct dst_entry **)&sk->sk_dst_cache, dst);
2030 	dst_release(old_dst);
2031 }
2032 
2033 static inline void
__sk_dst_reset(struct sock * sk)2034 __sk_dst_reset(struct sock *sk)
2035 {
2036 	__sk_dst_set(sk, NULL);
2037 }
2038 
2039 static inline void
sk_dst_reset(struct sock * sk)2040 sk_dst_reset(struct sock *sk)
2041 {
2042 	sk_dst_set(sk, NULL);
2043 }
2044 
2045 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
2046 
2047 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
2048 
sk_dst_confirm(struct sock * sk)2049 static inline void sk_dst_confirm(struct sock *sk)
2050 {
2051 	if (!READ_ONCE(sk->sk_dst_pending_confirm))
2052 		WRITE_ONCE(sk->sk_dst_pending_confirm, 1);
2053 }
2054 
sock_confirm_neigh(struct sk_buff * skb,struct neighbour * n)2055 static inline void sock_confirm_neigh(struct sk_buff *skb, struct neighbour *n)
2056 {
2057 	if (skb_get_dst_pending_confirm(skb)) {
2058 		struct sock *sk = skb->sk;
2059 		unsigned long now = jiffies;
2060 
2061 		/* avoid dirtying neighbour */
2062 		if (READ_ONCE(n->confirmed) != now)
2063 			WRITE_ONCE(n->confirmed, now);
2064 		if (sk && READ_ONCE(sk->sk_dst_pending_confirm))
2065 			WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2066 	}
2067 }
2068 
2069 bool sk_mc_loop(struct sock *sk);
2070 
sk_can_gso(const struct sock * sk)2071 static inline bool sk_can_gso(const struct sock *sk)
2072 {
2073 	return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type);
2074 }
2075 
2076 void sk_setup_caps(struct sock *sk, struct dst_entry *dst);
2077 
sk_nocaps_add(struct sock * sk,netdev_features_t flags)2078 static inline void sk_nocaps_add(struct sock *sk, netdev_features_t flags)
2079 {
2080 	sk->sk_route_nocaps |= flags;
2081 	sk->sk_route_caps &= ~flags;
2082 }
2083 
skb_do_copy_data_nocache(struct sock * sk,struct sk_buff * skb,struct iov_iter * from,char * to,int copy,int offset)2084 static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
2085 					   struct iov_iter *from, char *to,
2086 					   int copy, int offset)
2087 {
2088 	if (skb->ip_summed == CHECKSUM_NONE) {
2089 		__wsum csum = 0;
2090 		if (!csum_and_copy_from_iter_full(to, copy, &csum, from))
2091 			return -EFAULT;
2092 		skb->csum = csum_block_add(skb->csum, csum, offset);
2093 	} else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
2094 		if (!copy_from_iter_full_nocache(to, copy, from))
2095 			return -EFAULT;
2096 	} else if (!copy_from_iter_full(to, copy, from))
2097 		return -EFAULT;
2098 
2099 	return 0;
2100 }
2101 
skb_add_data_nocache(struct sock * sk,struct sk_buff * skb,struct iov_iter * from,int copy)2102 static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
2103 				       struct iov_iter *from, int copy)
2104 {
2105 	int err, offset = skb->len;
2106 
2107 	err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy),
2108 				       copy, offset);
2109 	if (err)
2110 		__skb_trim(skb, offset);
2111 
2112 	return err;
2113 }
2114 
skb_copy_to_page_nocache(struct sock * sk,struct iov_iter * from,struct sk_buff * skb,struct page * page,int off,int copy)2115 static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from,
2116 					   struct sk_buff *skb,
2117 					   struct page *page,
2118 					   int off, int copy)
2119 {
2120 	int err;
2121 
2122 	err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off,
2123 				       copy, skb->len);
2124 	if (err)
2125 		return err;
2126 
2127 	skb->len	     += copy;
2128 	skb->data_len	     += copy;
2129 	skb->truesize	     += copy;
2130 	sk_wmem_queued_add(sk, copy);
2131 	sk_mem_charge(sk, copy);
2132 	return 0;
2133 }
2134 
2135 /**
2136  * sk_wmem_alloc_get - returns write allocations
2137  * @sk: socket
2138  *
2139  * Return: sk_wmem_alloc minus initial offset of one
2140  */
sk_wmem_alloc_get(const struct sock * sk)2141 static inline int sk_wmem_alloc_get(const struct sock *sk)
2142 {
2143 	return refcount_read(&sk->sk_wmem_alloc) - 1;
2144 }
2145 
2146 /**
2147  * sk_rmem_alloc_get - returns read allocations
2148  * @sk: socket
2149  *
2150  * Return: sk_rmem_alloc
2151  */
sk_rmem_alloc_get(const struct sock * sk)2152 static inline int sk_rmem_alloc_get(const struct sock *sk)
2153 {
2154 	return atomic_read(&sk->sk_rmem_alloc);
2155 }
2156 
2157 /**
2158  * sk_has_allocations - check if allocations are outstanding
2159  * @sk: socket
2160  *
2161  * Return: true if socket has write or read allocations
2162  */
sk_has_allocations(const struct sock * sk)2163 static inline bool sk_has_allocations(const struct sock *sk)
2164 {
2165 	return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk);
2166 }
2167 
2168 /**
2169  * skwq_has_sleeper - check if there are any waiting processes
2170  * @wq: struct socket_wq
2171  *
2172  * Return: true if socket_wq has waiting processes
2173  *
2174  * The purpose of the skwq_has_sleeper and sock_poll_wait is to wrap the memory
2175  * barrier call. They were added due to the race found within the tcp code.
2176  *
2177  * Consider following tcp code paths::
2178  *
2179  *   CPU1                CPU2
2180  *   sys_select          receive packet
2181  *   ...                 ...
2182  *   __add_wait_queue    update tp->rcv_nxt
2183  *   ...                 ...
2184  *   tp->rcv_nxt check   sock_def_readable
2185  *   ...                 {
2186  *   schedule               rcu_read_lock();
2187  *                          wq = rcu_dereference(sk->sk_wq);
2188  *                          if (wq && waitqueue_active(&wq->wait))
2189  *                              wake_up_interruptible(&wq->wait)
2190  *                          ...
2191  *                       }
2192  *
2193  * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
2194  * in its cache, and so does the tp->rcv_nxt update on CPU2 side.  The CPU1
2195  * could then endup calling schedule and sleep forever if there are no more
2196  * data on the socket.
2197  *
2198  */
skwq_has_sleeper(struct socket_wq * wq)2199 static inline bool skwq_has_sleeper(struct socket_wq *wq)
2200 {
2201 	return wq && wq_has_sleeper(&wq->wait);
2202 }
2203 
2204 /**
2205  * sock_poll_wait - place memory barrier behind the poll_wait call.
2206  * @filp:           file
2207  * @sock:           socket to wait on
2208  * @p:              poll_table
2209  *
2210  * See the comments in the wq_has_sleeper function.
2211  */
sock_poll_wait(struct file * filp,struct socket * sock,poll_table * p)2212 static inline void sock_poll_wait(struct file *filp, struct socket *sock,
2213 				  poll_table *p)
2214 {
2215 	if (!poll_does_not_wait(p)) {
2216 		poll_wait(filp, &sock->wq.wait, p);
2217 		/* We need to be sure we are in sync with the
2218 		 * socket flags modification.
2219 		 *
2220 		 * This memory barrier is paired in the wq_has_sleeper.
2221 		 */
2222 		smp_mb();
2223 	}
2224 }
2225 
skb_set_hash_from_sk(struct sk_buff * skb,struct sock * sk)2226 static inline void skb_set_hash_from_sk(struct sk_buff *skb, struct sock *sk)
2227 {
2228 	/* This pairs with WRITE_ONCE() in sk_set_txhash() */
2229 	u32 txhash = READ_ONCE(sk->sk_txhash);
2230 
2231 	if (txhash) {
2232 		skb->l4_hash = 1;
2233 		skb->hash = txhash;
2234 	}
2235 }
2236 
2237 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk);
2238 
2239 /*
2240  *	Queue a received datagram if it will fit. Stream and sequenced
2241  *	protocols can't normally use this as they need to fit buffers in
2242  *	and play with them.
2243  *
2244  *	Inlined as it's very short and called for pretty much every
2245  *	packet ever received.
2246  */
skb_set_owner_r(struct sk_buff * skb,struct sock * sk)2247 static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
2248 {
2249 	skb_orphan(skb);
2250 	skb->sk = sk;
2251 	skb->destructor = sock_rfree;
2252 	atomic_add(skb->truesize, &sk->sk_rmem_alloc);
2253 	sk_mem_charge(sk, skb->truesize);
2254 }
2255 
skb_set_owner_sk_safe(struct sk_buff * skb,struct sock * sk)2256 static inline __must_check bool skb_set_owner_sk_safe(struct sk_buff *skb, struct sock *sk)
2257 {
2258 	if (sk && refcount_inc_not_zero(&sk->sk_refcnt)) {
2259 		skb_orphan(skb);
2260 		skb->destructor = sock_efree;
2261 		skb->sk = sk;
2262 		return true;
2263 	}
2264 	return false;
2265 }
2266 
2267 void sk_reset_timer(struct sock *sk, struct timer_list *timer,
2268 		    unsigned long expires);
2269 
2270 void sk_stop_timer(struct sock *sk, struct timer_list *timer);
2271 
2272 void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer);
2273 
2274 int __sk_queue_drop_skb(struct sock *sk, struct sk_buff_head *sk_queue,
2275 			struct sk_buff *skb, unsigned int flags,
2276 			void (*destructor)(struct sock *sk,
2277 					   struct sk_buff *skb));
2278 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
2279 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
2280 
2281 int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
2282 struct sk_buff *sock_dequeue_err_skb(struct sock *sk);
2283 
2284 /*
2285  *	Recover an error report and clear atomically
2286  */
2287 
sock_error(struct sock * sk)2288 static inline int sock_error(struct sock *sk)
2289 {
2290 	int err;
2291 
2292 	/* Avoid an atomic operation for the common case.
2293 	 * This is racy since another cpu/thread can change sk_err under us.
2294 	 */
2295 	if (likely(data_race(!sk->sk_err)))
2296 		return 0;
2297 
2298 	err = xchg(&sk->sk_err, 0);
2299 	return -err;
2300 }
2301 
sock_wspace(struct sock * sk)2302 static inline unsigned long sock_wspace(struct sock *sk)
2303 {
2304 	int amt = 0;
2305 
2306 	if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
2307 		amt = sk->sk_sndbuf - refcount_read(&sk->sk_wmem_alloc);
2308 		if (amt < 0)
2309 			amt = 0;
2310 	}
2311 	return amt;
2312 }
2313 
2314 /* Note:
2315  *  We use sk->sk_wq_raw, from contexts knowing this
2316  *  pointer is not NULL and cannot disappear/change.
2317  */
sk_set_bit(int nr,struct sock * sk)2318 static inline void sk_set_bit(int nr, struct sock *sk)
2319 {
2320 	if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2321 	    !sock_flag(sk, SOCK_FASYNC))
2322 		return;
2323 
2324 	set_bit(nr, &sk->sk_wq_raw->flags);
2325 }
2326 
sk_clear_bit(int nr,struct sock * sk)2327 static inline void sk_clear_bit(int nr, struct sock *sk)
2328 {
2329 	if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2330 	    !sock_flag(sk, SOCK_FASYNC))
2331 		return;
2332 
2333 	clear_bit(nr, &sk->sk_wq_raw->flags);
2334 }
2335 
sk_wake_async(const struct sock * sk,int how,int band)2336 static inline void sk_wake_async(const struct sock *sk, int how, int band)
2337 {
2338 	if (sock_flag(sk, SOCK_FASYNC)) {
2339 		rcu_read_lock();
2340 		sock_wake_async(rcu_dereference(sk->sk_wq), how, band);
2341 		rcu_read_unlock();
2342 	}
2343 }
2344 
2345 /* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might
2346  * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak.
2347  * Note: for send buffers, TCP works better if we can build two skbs at
2348  * minimum.
2349  */
2350 #define TCP_SKB_MIN_TRUESIZE	(2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff)))
2351 
2352 #define SOCK_MIN_SNDBUF		(TCP_SKB_MIN_TRUESIZE * 2)
2353 #define SOCK_MIN_RCVBUF		 TCP_SKB_MIN_TRUESIZE
2354 
sk_stream_moderate_sndbuf(struct sock * sk)2355 static inline void sk_stream_moderate_sndbuf(struct sock *sk)
2356 {
2357 	u32 val;
2358 
2359 	if (sk->sk_userlocks & SOCK_SNDBUF_LOCK)
2360 		return;
2361 
2362 	val = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
2363 
2364 	WRITE_ONCE(sk->sk_sndbuf, max_t(u32, val, SOCK_MIN_SNDBUF));
2365 }
2366 
2367 struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp,
2368 				    bool force_schedule);
2369 
2370 /**
2371  * sk_page_frag - return an appropriate page_frag
2372  * @sk: socket
2373  *
2374  * Use the per task page_frag instead of the per socket one for
2375  * optimization when we know that we're in process context and own
2376  * everything that's associated with %current.
2377  *
2378  * Both direct reclaim and page faults can nest inside other
2379  * socket operations and end up recursing into sk_page_frag()
2380  * while it's already in use: explicitly avoid task page_frag
2381  * usage if the caller is potentially doing any of them.
2382  * This assumes that page fault handlers use the GFP_NOFS flags.
2383  *
2384  * Return: a per task page_frag if context allows that,
2385  * otherwise a per socket one.
2386  */
sk_page_frag(struct sock * sk)2387 static inline struct page_frag *sk_page_frag(struct sock *sk)
2388 {
2389 	if ((sk->sk_allocation & (__GFP_DIRECT_RECLAIM | __GFP_MEMALLOC | __GFP_FS)) ==
2390 	    (__GFP_DIRECT_RECLAIM | __GFP_FS))
2391 		return &current->task_frag;
2392 
2393 	return &sk->sk_frag;
2394 }
2395 
2396 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag);
2397 
2398 /*
2399  *	Default write policy as shown to user space via poll/select/SIGIO
2400  */
sock_writeable(const struct sock * sk)2401 static inline bool sock_writeable(const struct sock *sk)
2402 {
2403 	return refcount_read(&sk->sk_wmem_alloc) < (READ_ONCE(sk->sk_sndbuf) >> 1);
2404 }
2405 
gfp_any(void)2406 static inline gfp_t gfp_any(void)
2407 {
2408 	return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2409 }
2410 
sock_rcvtimeo(const struct sock * sk,bool noblock)2411 static inline long sock_rcvtimeo(const struct sock *sk, bool noblock)
2412 {
2413 	return noblock ? 0 : sk->sk_rcvtimeo;
2414 }
2415 
sock_sndtimeo(const struct sock * sk,bool noblock)2416 static inline long sock_sndtimeo(const struct sock *sk, bool noblock)
2417 {
2418 	return noblock ? 0 : sk->sk_sndtimeo;
2419 }
2420 
sock_rcvlowat(const struct sock * sk,int waitall,int len)2421 static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
2422 {
2423 	int v = waitall ? len : min_t(int, READ_ONCE(sk->sk_rcvlowat), len);
2424 
2425 	return v ?: 1;
2426 }
2427 
2428 /* Alas, with timeout socket operations are not restartable.
2429  * Compare this to poll().
2430  */
sock_intr_errno(long timeo)2431 static inline int sock_intr_errno(long timeo)
2432 {
2433 	return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
2434 }
2435 
2436 struct sock_skb_cb {
2437 	u32 dropcount;
2438 };
2439 
2440 /* Store sock_skb_cb at the end of skb->cb[] so protocol families
2441  * using skb->cb[] would keep using it directly and utilize its
2442  * alignement guarantee.
2443  */
2444 #define SOCK_SKB_CB_OFFSET ((sizeof_field(struct sk_buff, cb) - \
2445 			    sizeof(struct sock_skb_cb)))
2446 
2447 #define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \
2448 			    SOCK_SKB_CB_OFFSET))
2449 
2450 #define sock_skb_cb_check_size(size) \
2451 	BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET)
2452 
2453 static inline void
sock_skb_set_dropcount(const struct sock * sk,struct sk_buff * skb)2454 sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb)
2455 {
2456 	SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, SOCK_RXQ_OVFL) ?
2457 						atomic_read(&sk->sk_drops) : 0;
2458 }
2459 
sk_drops_add(struct sock * sk,const struct sk_buff * skb)2460 static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb)
2461 {
2462 	int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs);
2463 
2464 	atomic_add(segs, &sk->sk_drops);
2465 }
2466 
sock_read_timestamp(struct sock * sk)2467 static inline ktime_t sock_read_timestamp(struct sock *sk)
2468 {
2469 #if BITS_PER_LONG==32
2470 	unsigned int seq;
2471 	ktime_t kt;
2472 
2473 	do {
2474 		seq = read_seqbegin(&sk->sk_stamp_seq);
2475 		kt = sk->sk_stamp;
2476 	} while (read_seqretry(&sk->sk_stamp_seq, seq));
2477 
2478 	return kt;
2479 #else
2480 	return READ_ONCE(sk->sk_stamp);
2481 #endif
2482 }
2483 
sock_write_timestamp(struct sock * sk,ktime_t kt)2484 static inline void sock_write_timestamp(struct sock *sk, ktime_t kt)
2485 {
2486 #if BITS_PER_LONG==32
2487 	write_seqlock(&sk->sk_stamp_seq);
2488 	sk->sk_stamp = kt;
2489 	write_sequnlock(&sk->sk_stamp_seq);
2490 #else
2491 	WRITE_ONCE(sk->sk_stamp, kt);
2492 #endif
2493 }
2494 
2495 void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
2496 			   struct sk_buff *skb);
2497 void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
2498 			     struct sk_buff *skb);
2499 
2500 static inline void
sock_recv_timestamp(struct msghdr * msg,struct sock * sk,struct sk_buff * skb)2501 sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
2502 {
2503 	ktime_t kt = skb->tstamp;
2504 	struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
2505 
2506 	/*
2507 	 * generate control messages if
2508 	 * - receive time stamping in software requested
2509 	 * - software time stamp available and wanted
2510 	 * - hardware time stamps available and wanted
2511 	 */
2512 	if (sock_flag(sk, SOCK_RCVTSTAMP) ||
2513 	    (sk->sk_tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) ||
2514 	    (kt && sk->sk_tsflags & SOF_TIMESTAMPING_SOFTWARE) ||
2515 	    (hwtstamps->hwtstamp &&
2516 	     (sk->sk_tsflags & SOF_TIMESTAMPING_RAW_HARDWARE)))
2517 		__sock_recv_timestamp(msg, sk, skb);
2518 	else
2519 		sock_write_timestamp(sk, kt);
2520 
2521 	if (sock_flag(sk, SOCK_WIFI_STATUS) && skb->wifi_acked_valid)
2522 		__sock_recv_wifi_status(msg, sk, skb);
2523 }
2524 
2525 void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2526 			      struct sk_buff *skb);
2527 
2528 #define SK_DEFAULT_STAMP (-1L * NSEC_PER_SEC)
sock_recv_ts_and_drops(struct msghdr * msg,struct sock * sk,struct sk_buff * skb)2529 static inline void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2530 					  struct sk_buff *skb)
2531 {
2532 #define FLAGS_TS_OR_DROPS ((1UL << SOCK_RXQ_OVFL)			| \
2533 			   (1UL << SOCK_RCVTSTAMP))
2534 #define TSFLAGS_ANY	  (SOF_TIMESTAMPING_SOFTWARE			| \
2535 			   SOF_TIMESTAMPING_RAW_HARDWARE)
2536 
2537 	if (sk->sk_flags & FLAGS_TS_OR_DROPS || sk->sk_tsflags & TSFLAGS_ANY)
2538 		__sock_recv_ts_and_drops(msg, sk, skb);
2539 	else if (unlikely(sock_flag(sk, SOCK_TIMESTAMP)))
2540 		sock_write_timestamp(sk, skb->tstamp);
2541 	else if (unlikely(sk->sk_stamp == SK_DEFAULT_STAMP))
2542 		sock_write_timestamp(sk, 0);
2543 }
2544 
2545 void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags);
2546 
2547 /**
2548  * _sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
2549  * @sk:		socket sending this packet
2550  * @tsflags:	timestamping flags to use
2551  * @tx_flags:	completed with instructions for time stamping
2552  * @tskey:      filled in with next sk_tskey (not for TCP, which uses seqno)
2553  *
2554  * Note: callers should take care of initial ``*tx_flags`` value (usually 0)
2555  */
_sock_tx_timestamp(struct sock * sk,__u16 tsflags,__u8 * tx_flags,__u32 * tskey)2556 static inline void _sock_tx_timestamp(struct sock *sk, __u16 tsflags,
2557 				      __u8 *tx_flags, __u32 *tskey)
2558 {
2559 	if (unlikely(tsflags)) {
2560 		__sock_tx_timestamp(tsflags, tx_flags);
2561 		if (tsflags & SOF_TIMESTAMPING_OPT_ID && tskey &&
2562 		    tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK)
2563 			*tskey = sk->sk_tskey++;
2564 	}
2565 	if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS)))
2566 		*tx_flags |= SKBTX_WIFI_STATUS;
2567 }
2568 
sock_tx_timestamp(struct sock * sk,__u16 tsflags,__u8 * tx_flags)2569 static inline void sock_tx_timestamp(struct sock *sk, __u16 tsflags,
2570 				     __u8 *tx_flags)
2571 {
2572 	_sock_tx_timestamp(sk, tsflags, tx_flags, NULL);
2573 }
2574 
skb_setup_tx_timestamp(struct sk_buff * skb,__u16 tsflags)2575 static inline void skb_setup_tx_timestamp(struct sk_buff *skb, __u16 tsflags)
2576 {
2577 	_sock_tx_timestamp(skb->sk, tsflags, &skb_shinfo(skb)->tx_flags,
2578 			   &skb_shinfo(skb)->tskey);
2579 }
2580 
2581 DECLARE_STATIC_KEY_FALSE(tcp_rx_skb_cache_key);
2582 /**
2583  * sk_eat_skb - Release a skb if it is no longer needed
2584  * @sk: socket to eat this skb from
2585  * @skb: socket buffer to eat
2586  *
2587  * This routine must be called with interrupts disabled or with the socket
2588  * locked so that the sk_buff queue operation is ok.
2589 */
sk_eat_skb(struct sock * sk,struct sk_buff * skb)2590 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb)
2591 {
2592 	__skb_unlink(skb, &sk->sk_receive_queue);
2593 	if (static_branch_unlikely(&tcp_rx_skb_cache_key) &&
2594 	    !sk->sk_rx_skb_cache) {
2595 		sk->sk_rx_skb_cache = skb;
2596 		skb_orphan(skb);
2597 		return;
2598 	}
2599 	__kfree_skb(skb);
2600 }
2601 
2602 static inline
sock_net(const struct sock * sk)2603 struct net *sock_net(const struct sock *sk)
2604 {
2605 	return read_pnet(&sk->sk_net);
2606 }
2607 
2608 static inline
sock_net_set(struct sock * sk,struct net * net)2609 void sock_net_set(struct sock *sk, struct net *net)
2610 {
2611 	write_pnet(&sk->sk_net, net);
2612 }
2613 
2614 static inline bool
skb_sk_is_prefetched(struct sk_buff * skb)2615 skb_sk_is_prefetched(struct sk_buff *skb)
2616 {
2617 #ifdef CONFIG_INET
2618 	return skb->destructor == sock_pfree;
2619 #else
2620 	return false;
2621 #endif /* CONFIG_INET */
2622 }
2623 
2624 /* This helper checks if a socket is a full socket,
2625  * ie _not_ a timewait or request socket.
2626  */
sk_fullsock(const struct sock * sk)2627 static inline bool sk_fullsock(const struct sock *sk)
2628 {
2629 	return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV);
2630 }
2631 
2632 static inline bool
sk_is_refcounted(struct sock * sk)2633 sk_is_refcounted(struct sock *sk)
2634 {
2635 	/* Only full sockets have sk->sk_flags. */
2636 	return !sk_fullsock(sk) || !sock_flag(sk, SOCK_RCU_FREE);
2637 }
2638 
2639 /**
2640  * skb_steal_sock - steal a socket from an sk_buff
2641  * @skb: sk_buff to steal the socket from
2642  * @refcounted: is set to true if the socket is reference-counted
2643  */
2644 static inline struct sock *
skb_steal_sock(struct sk_buff * skb,bool * refcounted)2645 skb_steal_sock(struct sk_buff *skb, bool *refcounted)
2646 {
2647 	if (skb->sk) {
2648 		struct sock *sk = skb->sk;
2649 
2650 		*refcounted = true;
2651 		if (skb_sk_is_prefetched(skb))
2652 			*refcounted = sk_is_refcounted(sk);
2653 		skb->destructor = NULL;
2654 		skb->sk = NULL;
2655 		return sk;
2656 	}
2657 	*refcounted = false;
2658 	return NULL;
2659 }
2660 
2661 /* Checks if this SKB belongs to an HW offloaded socket
2662  * and whether any SW fallbacks are required based on dev.
2663  * Check decrypted mark in case skb_orphan() cleared socket.
2664  */
sk_validate_xmit_skb(struct sk_buff * skb,struct net_device * dev)2665 static inline struct sk_buff *sk_validate_xmit_skb(struct sk_buff *skb,
2666 						   struct net_device *dev)
2667 {
2668 #ifdef CONFIG_SOCK_VALIDATE_XMIT
2669 	struct sock *sk = skb->sk;
2670 
2671 	if (sk && sk_fullsock(sk) && sk->sk_validate_xmit_skb) {
2672 		skb = sk->sk_validate_xmit_skb(sk, dev, skb);
2673 #ifdef CONFIG_TLS_DEVICE
2674 	} else if (unlikely(skb->decrypted)) {
2675 		pr_warn_ratelimited("unencrypted skb with no associated socket - dropping\n");
2676 		kfree_skb(skb);
2677 		skb = NULL;
2678 #endif
2679 	}
2680 #endif
2681 
2682 	return skb;
2683 }
2684 
2685 /* This helper checks if a socket is a LISTEN or NEW_SYN_RECV
2686  * SYNACK messages can be attached to either ones (depending on SYNCOOKIE)
2687  */
sk_listener(const struct sock * sk)2688 static inline bool sk_listener(const struct sock *sk)
2689 {
2690 	return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV);
2691 }
2692 
2693 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag);
2694 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level,
2695 		       int type);
2696 
2697 bool sk_ns_capable(const struct sock *sk,
2698 		   struct user_namespace *user_ns, int cap);
2699 bool sk_capable(const struct sock *sk, int cap);
2700 bool sk_net_capable(const struct sock *sk, int cap);
2701 
2702 void sk_get_meminfo(const struct sock *sk, u32 *meminfo);
2703 
2704 /* Take into consideration the size of the struct sk_buff overhead in the
2705  * determination of these values, since that is non-constant across
2706  * platforms.  This makes socket queueing behavior and performance
2707  * not depend upon such differences.
2708  */
2709 #define _SK_MEM_PACKETS		256
2710 #define _SK_MEM_OVERHEAD	SKB_TRUESIZE(256)
2711 #define SK_WMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2712 #define SK_RMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2713 
2714 extern __u32 sysctl_wmem_max;
2715 extern __u32 sysctl_rmem_max;
2716 
2717 extern int sysctl_tstamp_allow_data;
2718 extern int sysctl_optmem_max;
2719 
2720 extern __u32 sysctl_wmem_default;
2721 extern __u32 sysctl_rmem_default;
2722 
2723 #define SKB_FRAG_PAGE_ORDER	get_order(32768)
2724 DECLARE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
2725 
sk_get_wmem0(const struct sock * sk,const struct proto * proto)2726 static inline int sk_get_wmem0(const struct sock *sk, const struct proto *proto)
2727 {
2728 	/* Does this proto have per netns sysctl_wmem ? */
2729 	if (proto->sysctl_wmem_offset)
2730 		return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_wmem_offset));
2731 
2732 	return READ_ONCE(*proto->sysctl_wmem);
2733 }
2734 
sk_get_rmem0(const struct sock * sk,const struct proto * proto)2735 static inline int sk_get_rmem0(const struct sock *sk, const struct proto *proto)
2736 {
2737 	/* Does this proto have per netns sysctl_rmem ? */
2738 	if (proto->sysctl_rmem_offset)
2739 		return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_rmem_offset));
2740 
2741 	return READ_ONCE(*proto->sysctl_rmem);
2742 }
2743 
2744 /* Default TCP Small queue budget is ~1 ms of data (1sec >> 10)
2745  * Some wifi drivers need to tweak it to get more chunks.
2746  * They can use this helper from their ndo_start_xmit()
2747  */
sk_pacing_shift_update(struct sock * sk,int val)2748 static inline void sk_pacing_shift_update(struct sock *sk, int val)
2749 {
2750 	if (!sk || !sk_fullsock(sk) || READ_ONCE(sk->sk_pacing_shift) == val)
2751 		return;
2752 	WRITE_ONCE(sk->sk_pacing_shift, val);
2753 }
2754 
2755 /* if a socket is bound to a device, check that the given device
2756  * index is either the same or that the socket is bound to an L3
2757  * master device and the given device index is also enslaved to
2758  * that L3 master
2759  */
sk_dev_equal_l3scope(struct sock * sk,int dif)2760 static inline bool sk_dev_equal_l3scope(struct sock *sk, int dif)
2761 {
2762 	int mdif;
2763 
2764 	if (!sk->sk_bound_dev_if || sk->sk_bound_dev_if == dif)
2765 		return true;
2766 
2767 	mdif = l3mdev_master_ifindex_by_index(sock_net(sk), dif);
2768 	if (mdif && mdif == sk->sk_bound_dev_if)
2769 		return true;
2770 
2771 	return false;
2772 }
2773 
2774 void sock_def_readable(struct sock *sk);
2775 
2776 int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk);
2777 void sock_enable_timestamps(struct sock *sk);
2778 void sock_no_linger(struct sock *sk);
2779 void sock_set_keepalive(struct sock *sk);
2780 void sock_set_priority(struct sock *sk, u32 priority);
2781 void sock_set_rcvbuf(struct sock *sk, int val);
2782 void sock_set_mark(struct sock *sk, u32 val);
2783 void sock_set_reuseaddr(struct sock *sk);
2784 void sock_set_reuseport(struct sock *sk);
2785 void sock_set_sndtimeo(struct sock *sk, s64 secs);
2786 
2787 int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len);
2788 
2789 #endif	/* _SOCK_H */
2790