sock.h 68.0 KB
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/*
 * INET		An implementation of the TCP/IP protocol suite for the LINUX
 *		operating system.  INET is implemented using the  BSD Socket
 *		interface as the means of communication with the user level.
 *
 *		Definitions for the AF_INET socket handler.
 *
 * Version:	@(#)sock.h	1.0.4	05/13/93
 *
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 * Authors:	Ross Biro
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 *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
 *		Corey Minyard <wf-rch!minyard@relay.EU.net>
 *		Florian La Roche <flla@stud.uni-sb.de>
 *
 * Fixes:
 *		Alan Cox	:	Volatiles in skbuff pointers. See
 *					skbuff comments. May be overdone,
 *					better to prove they can be removed
 *					than the reverse.
 *		Alan Cox	:	Added a zapped field for tcp to note
 *					a socket is reset and must stay shut up
 *		Alan Cox	:	New fields for options
 *	Pauline Middelink	:	identd support
 *		Alan Cox	:	Eliminate low level recv/recvfrom
 *		David S. Miller	:	New socket lookup architecture.
 *              Steve Whitehouse:       Default routines for sock_ops
 *              Arnaldo C. Melo :	removed net_pinfo, tp_pinfo and made
 *              			protinfo be just a void pointer, as the
 *              			protocol specific parts were moved to
 *              			respective headers and ipv4/v6, etc now
 *              			use private slabcaches for its socks
 *              Pedro Hortas	:	New flags field for socket options
 *
 *
 *		This program is free software; you can redistribute it and/or
 *		modify it under the terms of the GNU General Public License
 *		as published by the Free Software Foundation; either version
 *		2 of the License, or (at your option) any later version.
 */
#ifndef _SOCK_H
#define _SOCK_H

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#include <linux/hardirq.h>
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#include <linux/kernel.h>
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#include <linux/list.h>
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#include <linux/list_nulls.h>
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#include <linux/timer.h>
#include <linux/cache.h>
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#include <linux/bitops.h>
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#include <linux/lockdep.h>
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#include <linux/netdevice.h>
#include <linux/skbuff.h>	/* struct sk_buff */
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#include <linux/mm.h>
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#include <linux/security.h>
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#include <linux/slab.h>
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#include <linux/uaccess.h>
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#include <linux/page_counter.h>
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#include <linux/memcontrol.h>
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#include <linux/static_key.h>
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#include <linux/sched.h>
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#include <linux/wait.h>
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#include <linux/cgroup-defs.h>
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#include <linux/rbtree.h>
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#include <linux/filter.h>
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#include <linux/rculist_nulls.h>
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#include <linux/poll.h>
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#include <linux/atomic.h>
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#include <linux/refcount.h>
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#include <net/dst.h>
#include <net/checksum.h>
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#include <net/tcp_states.h>
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#include <linux/net_tstamp.h>
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#include <net/smc.h>
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#include <net/l3mdev.h>
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/*
 * This structure really needs to be cleaned up.
 * Most of it is for TCP, and not used by any of
 * the other protocols.
 */

/* Define this to get the SOCK_DBG debugging facility. */
#define SOCK_DEBUGGING
#ifdef SOCK_DEBUGGING
#define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \
					printk(KERN_DEBUG msg); } while (0)
#else
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/* Validate arguments and do nothing */
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static inline __printf(2, 3)
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void SOCK_DEBUG(const struct sock *sk, const char *msg, ...)
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{
}
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#endif

/* This is the per-socket lock.  The spinlock provides a synchronization
 * between user contexts and software interrupt processing, whereas the
 * mini-semaphore synchronizes multiple users amongst themselves.
 */
typedef struct {
	spinlock_t		slock;
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	int			owned;
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	wait_queue_head_t	wq;
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	/*
	 * We express the mutex-alike socket_lock semantics
	 * to the lock validator by explicitly managing
	 * the slock as a lock variant (in addition to
	 * the slock itself):
	 */
#ifdef CONFIG_DEBUG_LOCK_ALLOC
	struct lockdep_map dep_map;
#endif
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} socket_lock_t;

struct sock;
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struct proto;
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struct net;
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typedef __u32 __bitwise __portpair;
typedef __u64 __bitwise __addrpair;

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/**
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 *	struct sock_common - minimal network layer representation of sockets
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 *	@skc_daddr: Foreign IPv4 addr
 *	@skc_rcv_saddr: Bound local IPv4 addr
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 *	@skc_hash: hash value used with various protocol lookup tables
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 *	@skc_u16hashes: two u16 hash values used by UDP lookup tables
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 *	@skc_dport: placeholder for inet_dport/tw_dport
 *	@skc_num: placeholder for inet_num/tw_num
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 *	@skc_family: network address family
 *	@skc_state: Connection state
 *	@skc_reuse: %SO_REUSEADDR setting
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 *	@skc_reuseport: %SO_REUSEPORT setting
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 *	@skc_bound_dev_if: bound device index if != 0
 *	@skc_bind_node: bind hash linkage for various protocol lookup tables
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 *	@skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol
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 *	@skc_prot: protocol handlers inside a network family
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 *	@skc_net: reference to the network namespace of this socket
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 *	@skc_node: main hash linkage for various protocol lookup tables
 *	@skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol
 *	@skc_tx_queue_mapping: tx queue number for this connection
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 *	@skc_flags: place holder for sk_flags
 *		%SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE,
 *		%SO_OOBINLINE settings, %SO_TIMESTAMPING settings
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 *	@skc_incoming_cpu: record/match cpu processing incoming packets
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 *	@skc_refcnt: reference count
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 *
 *	This is the minimal network layer representation of sockets, the header
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 *	for struct sock and struct inet_timewait_sock.
 */
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struct sock_common {
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	/* skc_daddr and skc_rcv_saddr must be grouped on a 8 bytes aligned
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	 * address on 64bit arches : cf INET_MATCH()
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	 */
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	union {
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		__addrpair	skc_addrpair;
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		struct {
			__be32	skc_daddr;
			__be32	skc_rcv_saddr;
		};
	};
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	union  {
		unsigned int	skc_hash;
		__u16		skc_u16hashes[2];
	};
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	/* skc_dport && skc_num must be grouped as well */
	union {
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		__portpair	skc_portpair;
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		struct {
			__be16	skc_dport;
			__u16	skc_num;
		};
	};

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	unsigned short		skc_family;
	volatile unsigned char	skc_state;
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	unsigned char		skc_reuse:4;
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	unsigned char		skc_reuseport:1;
	unsigned char		skc_ipv6only:1;
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	unsigned char		skc_net_refcnt:1;
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	int			skc_bound_dev_if;
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	union {
		struct hlist_node	skc_bind_node;
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		struct hlist_node	skc_portaddr_node;
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	};
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	struct proto		*skc_prot;
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	possible_net_t		skc_net;
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#if IS_ENABLED(CONFIG_IPV6)
	struct in6_addr		skc_v6_daddr;
	struct in6_addr		skc_v6_rcv_saddr;
#endif

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	atomic64_t		skc_cookie;

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	/* following fields are padding to force
	 * offset(struct sock, sk_refcnt) == 128 on 64bit arches
	 * assuming IPV6 is enabled. We use this padding differently
	 * for different kind of 'sockets'
	 */
	union {
		unsigned long	skc_flags;
		struct sock	*skc_listener; /* request_sock */
		struct inet_timewait_death_row *skc_tw_dr; /* inet_timewait_sock */
	};
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	/*
	 * fields between dontcopy_begin/dontcopy_end
	 * are not copied in sock_copy()
	 */
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	/* private: */
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	int			skc_dontcopy_begin[0];
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	/* public: */
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	union {
		struct hlist_node	skc_node;
		struct hlist_nulls_node skc_nulls_node;
	};
	int			skc_tx_queue_mapping;
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	union {
		int		skc_incoming_cpu;
		u32		skc_rcv_wnd;
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		u32		skc_tw_rcv_nxt; /* struct tcp_timewait_sock  */
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	};
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	refcount_t		skc_refcnt;
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	/* private: */
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	int                     skc_dontcopy_end[0];
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	union {
		u32		skc_rxhash;
		u32		skc_window_clamp;
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		u32		skc_tw_snd_nxt; /* struct tcp_timewait_sock */
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	};
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	/* public: */
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};

/**
  *	struct sock - network layer representation of sockets
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  *	@__sk_common: shared layout with inet_timewait_sock
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  *	@sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
  *	@sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
  *	@sk_lock:	synchronizer
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  *	@sk_kern_sock: True if sock is using kernel lock classes
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  *	@sk_rcvbuf: size of receive buffer in bytes
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  *	@sk_wq: sock wait queue and async head
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  *	@sk_rx_dst: receive input route used by early demux
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  *	@sk_dst_cache: destination cache
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  *	@sk_dst_pending_confirm: need to confirm neighbour
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  *	@sk_policy: flow policy
  *	@sk_receive_queue: incoming packets
  *	@sk_wmem_alloc: transmit queue bytes committed
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  *	@sk_tsq_flags: TCP Small Queues flags
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  *	@sk_write_queue: Packet sending queue
  *	@sk_omem_alloc: "o" is "option" or "other"
  *	@sk_wmem_queued: persistent queue size
  *	@sk_forward_alloc: space allocated forward
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  *	@sk_napi_id: id of the last napi context to receive data for sk
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  *	@sk_ll_usec: usecs to busypoll when there is no data
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  *	@sk_allocation: allocation mode
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  *	@sk_pacing_rate: Pacing rate (if supported by transport/packet scheduler)
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  *	@sk_pacing_status: Pacing status (requested, handled by sch_fq)
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  *	@sk_max_pacing_rate: Maximum pacing rate (%SO_MAX_PACING_RATE)
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  *	@sk_sndbuf: size of send buffer in bytes
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  *	@__sk_flags_offset: empty field used to determine location of bitfield
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  *	@sk_padding: unused element for alignment
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  *	@sk_no_check_tx: %SO_NO_CHECK setting, set checksum in TX packets
  *	@sk_no_check_rx: allow zero checksum in RX packets
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  *	@sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
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  *	@sk_route_nocaps: forbidden route capabilities (e.g NETIF_F_GSO_MASK)
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  *	@sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
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  *	@sk_gso_max_size: Maximum GSO segment size to build
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  *	@sk_gso_max_segs: Maximum number of GSO segments
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  *	@sk_pacing_shift: scaling factor for TCP Small Queues
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  *	@sk_lingertime: %SO_LINGER l_linger setting
  *	@sk_backlog: always used with the per-socket spinlock held
  *	@sk_callback_lock: used with the callbacks in the end of this struct
  *	@sk_error_queue: rarely used
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  *	@sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt,
  *			  IPV6_ADDRFORM for instance)
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  *	@sk_err: last error
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  *	@sk_err_soft: errors that don't cause failure but are the cause of a
  *		      persistent failure not just 'timed out'
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  *	@sk_drops: raw/udp drops counter
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  *	@sk_ack_backlog: current listen backlog
  *	@sk_max_ack_backlog: listen backlog set in listen()
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  *	@sk_uid: user id of owner
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  *	@sk_priority: %SO_PRIORITY setting
  *	@sk_type: socket type (%SOCK_STREAM, etc)
  *	@sk_protocol: which protocol this socket belongs in this network family
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  *	@sk_peer_pid: &struct pid for this socket's peer
  *	@sk_peer_cred: %SO_PEERCRED setting
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  *	@sk_rcvlowat: %SO_RCVLOWAT setting
  *	@sk_rcvtimeo: %SO_RCVTIMEO setting
  *	@sk_sndtimeo: %SO_SNDTIMEO setting
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  *	@sk_txhash: computed flow hash for use on transmit
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  *	@sk_filter: socket filtering instructions
  *	@sk_timer: sock cleanup timer
  *	@sk_stamp: time stamp of last packet received
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  *	@sk_tsflags: SO_TIMESTAMPING socket options
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  *	@sk_tskey: counter to disambiguate concurrent tstamp requests
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  *	@sk_zckey: counter to order MSG_ZEROCOPY notifications
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  *	@sk_socket: Identd and reporting IO signals
  *	@sk_user_data: RPC layer private data
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  *	@sk_frag: cached page frag
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  *	@sk_peek_off: current peek_offset value
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  *	@sk_send_head: front of stuff to transmit
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  *	@sk_security: used by security modules
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  *	@sk_mark: generic packet mark
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  *	@sk_cgrp_data: cgroup data for this cgroup
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  *	@sk_memcg: this socket's memory cgroup association
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  *	@sk_write_pending: a write to stream socket waits to start
  *	@sk_state_change: callback to indicate change in the state of the sock
  *	@sk_data_ready: callback to indicate there is data to be processed
  *	@sk_write_space: callback to indicate there is bf sending space available
  *	@sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
  *	@sk_backlog_rcv: callback to process the backlog
  *	@sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
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  *	@sk_reuseport_cb: reuseport group container
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  *	@sk_rcu: used during RCU grace period
  */
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struct sock {
	/*
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	 * Now struct inet_timewait_sock also uses sock_common, so please just
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	 * don't add nothing before this first member (__sk_common) --acme
	 */
	struct sock_common	__sk_common;
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#define sk_node			__sk_common.skc_node
#define sk_nulls_node		__sk_common.skc_nulls_node
#define sk_refcnt		__sk_common.skc_refcnt
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#define sk_tx_queue_mapping	__sk_common.skc_tx_queue_mapping
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#define sk_dontcopy_begin	__sk_common.skc_dontcopy_begin
#define sk_dontcopy_end		__sk_common.skc_dontcopy_end
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#define sk_hash			__sk_common.skc_hash
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#define sk_portpair		__sk_common.skc_portpair
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#define sk_num			__sk_common.skc_num
#define sk_dport		__sk_common.skc_dport
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#define sk_addrpair		__sk_common.skc_addrpair
#define sk_daddr		__sk_common.skc_daddr
#define sk_rcv_saddr		__sk_common.skc_rcv_saddr
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#define sk_family		__sk_common.skc_family
#define sk_state		__sk_common.skc_state
#define sk_reuse		__sk_common.skc_reuse
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#define sk_reuseport		__sk_common.skc_reuseport
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#define sk_ipv6only		__sk_common.skc_ipv6only
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#define sk_net_refcnt		__sk_common.skc_net_refcnt
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#define sk_bound_dev_if		__sk_common.skc_bound_dev_if
#define sk_bind_node		__sk_common.skc_bind_node
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#define sk_prot			__sk_common.skc_prot
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#define sk_net			__sk_common.skc_net
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#define sk_v6_daddr		__sk_common.skc_v6_daddr
#define sk_v6_rcv_saddr	__sk_common.skc_v6_rcv_saddr
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#define sk_cookie		__sk_common.skc_cookie
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#define sk_incoming_cpu		__sk_common.skc_incoming_cpu
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#define sk_flags		__sk_common.skc_flags
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#define sk_rxhash		__sk_common.skc_rxhash
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	socket_lock_t		sk_lock;
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	atomic_t		sk_drops;
	int			sk_rcvlowat;
	struct sk_buff_head	sk_error_queue;
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	struct sk_buff_head	sk_receive_queue;
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	/*
	 * The backlog queue is special, it is always used with
	 * the per-socket spinlock held and requires low latency
	 * access. Therefore we special case it's implementation.
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	 * Note : rmem_alloc is in this structure to fill a hole
	 * on 64bit arches, not because its logically part of
	 * backlog.
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	 */
	struct {
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		atomic_t	rmem_alloc;
		int		len;
		struct sk_buff	*head;
		struct sk_buff	*tail;
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	} sk_backlog;
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#define sk_rmem_alloc sk_backlog.rmem_alloc
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	int			sk_forward_alloc;
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#ifdef CONFIG_NET_RX_BUSY_POLL
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	unsigned int		sk_ll_usec;
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	/* ===== mostly read cache line ===== */
	unsigned int		sk_napi_id;
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#endif
	int			sk_rcvbuf;

	struct sk_filter __rcu	*sk_filter;
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	union {
		struct socket_wq __rcu	*sk_wq;
		struct socket_wq	*sk_wq_raw;
	};
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#ifdef CONFIG_XFRM
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	struct xfrm_policy __rcu *sk_policy[2];
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#endif
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	struct dst_entry	*sk_rx_dst;
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	struct dst_entry __rcu	*sk_dst_cache;
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	atomic_t		sk_omem_alloc;
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	int			sk_sndbuf;
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	/* ===== cache line for TX ===== */
	int			sk_wmem_queued;
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	refcount_t		sk_wmem_alloc;
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	unsigned long		sk_tsq_flags;
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	union {
		struct sk_buff	*sk_send_head;
		struct rb_root	tcp_rtx_queue;
	};
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	struct sk_buff_head	sk_write_queue;
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	__s32			sk_peek_off;
	int			sk_write_pending;
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	__u32			sk_dst_pending_confirm;
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	u32			sk_pacing_status; /* see enum sk_pacing */
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	long			sk_sndtimeo;
	struct timer_list	sk_timer;
	__u32			sk_priority;
	__u32			sk_mark;
	u32			sk_pacing_rate; /* bytes per second */
	u32			sk_max_pacing_rate;
	struct page_frag	sk_frag;
	netdev_features_t	sk_route_caps;
	netdev_features_t	sk_route_nocaps;
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	netdev_features_t	sk_route_forced_caps;
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	int			sk_gso_type;
	unsigned int		sk_gso_max_size;
	gfp_t			sk_allocation;
	__u32			sk_txhash;
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	/*
	 * Because of non atomicity rules, all
	 * changes are protected by socket lock.
	 */
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	unsigned int		__sk_flags_offset[0];
#ifdef __BIG_ENDIAN_BITFIELD
#define SK_FL_PROTO_SHIFT  16
#define SK_FL_PROTO_MASK   0x00ff0000

#define SK_FL_TYPE_SHIFT   0
#define SK_FL_TYPE_MASK    0x0000ffff
#else
#define SK_FL_PROTO_SHIFT  8
#define SK_FL_PROTO_MASK   0x0000ff00

#define SK_FL_TYPE_SHIFT   16
#define SK_FL_TYPE_MASK    0xffff0000
#endif

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	unsigned int		sk_padding : 1,
				sk_kern_sock : 1,
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				sk_no_check_tx : 1,
				sk_no_check_rx : 1,
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				sk_userlocks : 4,
				sk_protocol  : 8,
				sk_type      : 16;
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#define SK_PROTOCOL_MAX U8_MAX
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	u16			sk_gso_max_segs;
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	u8			sk_pacing_shift;
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	unsigned long	        sk_lingertime;
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	struct proto		*sk_prot_creator;
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	rwlock_t		sk_callback_lock;
	int			sk_err,
				sk_err_soft;
460 461
	u32			sk_ack_backlog;
	u32			sk_max_ack_backlog;
462
	kuid_t			sk_uid;
463 464
	struct pid		*sk_peer_pid;
	const struct cred	*sk_peer_cred;
L
Linus Torvalds 已提交
465
	long			sk_rcvtimeo;
466
	ktime_t			sk_stamp;
467
	u16			sk_tsflags;
468
	u8			sk_shutdown;
469
	u32			sk_tskey;
W
Willem de Bruijn 已提交
470
	atomic_t		sk_zckey;
L
Linus Torvalds 已提交
471 472
	struct socket		*sk_socket;
	void			*sk_user_data;
A
Alexey Dobriyan 已提交
473
#ifdef CONFIG_SECURITY
L
Linus Torvalds 已提交
474
	void			*sk_security;
A
Alexey Dobriyan 已提交
475
#endif
476
	struct sock_cgroup_data	sk_cgrp_data;
477
	struct mem_cgroup	*sk_memcg;
L
Linus Torvalds 已提交
478
	void			(*sk_state_change)(struct sock *sk);
479
	void			(*sk_data_ready)(struct sock *sk);
L
Linus Torvalds 已提交
480 481
	void			(*sk_write_space)(struct sock *sk);
	void			(*sk_error_report)(struct sock *sk);
E
Eric Dumazet 已提交
482 483
	int			(*sk_backlog_rcv)(struct sock *sk,
						  struct sk_buff *skb);
L
Linus Torvalds 已提交
484
	void                    (*sk_destruct)(struct sock *sk);
485
	struct sock_reuseport __rcu	*sk_reuseport_cb;
486
	struct rcu_head		sk_rcu;
L
Linus Torvalds 已提交
487 488
};

489 490 491 492 493 494
enum sk_pacing {
	SK_PACING_NONE		= 0,
	SK_PACING_NEEDED	= 1,
	SK_PACING_FQ		= 2,
};

495 496 497 498 499
#define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data)))

#define rcu_dereference_sk_user_data(sk)	rcu_dereference(__sk_user_data((sk)))
#define rcu_assign_sk_user_data(sk, ptr)	rcu_assign_pointer(__sk_user_data((sk)), ptr)

500 501 502 503 504 505 506 507 508 509 510
/*
 * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK
 * or not whether his port will be reused by someone else. SK_FORCE_REUSE
 * on a socket means that the socket will reuse everybody else's port
 * without looking at the other's sk_reuse value.
 */

#define SK_NO_REUSE	0
#define SK_CAN_REUSE	1
#define SK_FORCE_REUSE	2

511 512
int sk_set_peek_off(struct sock *sk, int val);

513 514
static inline int sk_peek_offset(struct sock *sk, int flags)
{
515
	if (unlikely(flags & MSG_PEEK)) {
516
		return READ_ONCE(sk->sk_peek_off);
517 518 519
	}

	return 0;
520 521 522 523
}

static inline void sk_peek_offset_bwd(struct sock *sk, int val)
{
524 525 526 527 528
	s32 off = READ_ONCE(sk->sk_peek_off);

	if (unlikely(off >= 0)) {
		off = max_t(s32, off - val, 0);
		WRITE_ONCE(sk->sk_peek_off, off);
529 530 531 532 533
	}
}

static inline void sk_peek_offset_fwd(struct sock *sk, int val)
{
534
	sk_peek_offset_bwd(sk, -val);
535 536
}

L
Linus Torvalds 已提交
537 538 539
/*
 * Hashed lists helper routines
 */
L
Li Zefan 已提交
540 541 542 543 544
static inline struct sock *sk_entry(const struct hlist_node *node)
{
	return hlist_entry(node, struct sock, sk_node);
}

545
static inline struct sock *__sk_head(const struct hlist_head *head)
L
Linus Torvalds 已提交
546 547 548 549
{
	return hlist_entry(head->first, struct sock, sk_node);
}

550
static inline struct sock *sk_head(const struct hlist_head *head)
L
Linus Torvalds 已提交
551 552 553 554
{
	return hlist_empty(head) ? NULL : __sk_head(head);
}

555 556 557 558 559 560 561 562 563 564
static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head)
{
	return hlist_nulls_entry(head->first, struct sock, sk_nulls_node);
}

static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head)
{
	return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head);
}

565
static inline struct sock *sk_next(const struct sock *sk)
L
Linus Torvalds 已提交
566
{
G
Geliang Tang 已提交
567
	return hlist_entry_safe(sk->sk_node.next, struct sock, sk_node);
L
Linus Torvalds 已提交
568 569
}

570 571 572 573 574 575 576 577
static inline struct sock *sk_nulls_next(const struct sock *sk)
{
	return (!is_a_nulls(sk->sk_nulls_node.next)) ?
		hlist_nulls_entry(sk->sk_nulls_node.next,
				  struct sock, sk_nulls_node) :
		NULL;
}

E
Eric Dumazet 已提交
578
static inline bool sk_unhashed(const struct sock *sk)
L
Linus Torvalds 已提交
579 580 581 582
{
	return hlist_unhashed(&sk->sk_node);
}

E
Eric Dumazet 已提交
583
static inline bool sk_hashed(const struct sock *sk)
L
Linus Torvalds 已提交
584
{
A
Akinobu Mita 已提交
585
	return !sk_unhashed(sk);
L
Linus Torvalds 已提交
586 587
}

E
Eric Dumazet 已提交
588
static inline void sk_node_init(struct hlist_node *node)
L
Linus Torvalds 已提交
589 590 591 592
{
	node->pprev = NULL;
}

E
Eric Dumazet 已提交
593
static inline void sk_nulls_node_init(struct hlist_nulls_node *node)
594 595 596 597
{
	node->pprev = NULL;
}

E
Eric Dumazet 已提交
598
static inline void __sk_del_node(struct sock *sk)
L
Linus Torvalds 已提交
599 600 601 602
{
	__hlist_del(&sk->sk_node);
}

603
/* NB: equivalent to hlist_del_init_rcu */
E
Eric Dumazet 已提交
604
static inline bool __sk_del_node_init(struct sock *sk)
L
Linus Torvalds 已提交
605 606 607 608
{
	if (sk_hashed(sk)) {
		__sk_del_node(sk);
		sk_node_init(&sk->sk_node);
E
Eric Dumazet 已提交
609
		return true;
L
Linus Torvalds 已提交
610
	}
E
Eric Dumazet 已提交
611
	return false;
L
Linus Torvalds 已提交
612 613 614 615 616 617 618 619
}

/* Grab socket reference count. This operation is valid only
   when sk is ALREADY grabbed f.e. it is found in hash table
   or a list and the lookup is made under lock preventing hash table
   modifications.
 */

620
static __always_inline void sock_hold(struct sock *sk)
L
Linus Torvalds 已提交
621
{
622
	refcount_inc(&sk->sk_refcnt);
L
Linus Torvalds 已提交
623 624 625 626 627
}

/* Ungrab socket in the context, which assumes that socket refcnt
   cannot hit zero, f.e. it is true in context of any socketcall.
 */
628
static __always_inline void __sock_put(struct sock *sk)
L
Linus Torvalds 已提交
629
{
630
	refcount_dec(&sk->sk_refcnt);
L
Linus Torvalds 已提交
631 632
}

E
Eric Dumazet 已提交
633
static inline bool sk_del_node_init(struct sock *sk)
L
Linus Torvalds 已提交
634
{
E
Eric Dumazet 已提交
635
	bool rc = __sk_del_node_init(sk);
L
Linus Torvalds 已提交
636 637 638

	if (rc) {
		/* paranoid for a while -acme */
639
		WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
L
Linus Torvalds 已提交
640 641 642 643
		__sock_put(sk);
	}
	return rc;
}
644
#define sk_del_node_init_rcu(sk)	sk_del_node_init(sk)
L
Linus Torvalds 已提交
645

E
Eric Dumazet 已提交
646
static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk)
647 648
{
	if (sk_hashed(sk)) {
649
		hlist_nulls_del_init_rcu(&sk->sk_nulls_node);
E
Eric Dumazet 已提交
650
		return true;
651
	}
E
Eric Dumazet 已提交
652
	return false;
653 654
}

E
Eric Dumazet 已提交
655
static inline bool sk_nulls_del_node_init_rcu(struct sock *sk)
656
{
E
Eric Dumazet 已提交
657
	bool rc = __sk_nulls_del_node_init_rcu(sk);
658 659 660

	if (rc) {
		/* paranoid for a while -acme */
661
		WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
662 663 664 665 666
		__sock_put(sk);
	}
	return rc;
}

E
Eric Dumazet 已提交
667
static inline void __sk_add_node(struct sock *sk, struct hlist_head *list)
L
Linus Torvalds 已提交
668 669 670 671
{
	hlist_add_head(&sk->sk_node, list);
}

E
Eric Dumazet 已提交
672
static inline void sk_add_node(struct sock *sk, struct hlist_head *list)
L
Linus Torvalds 已提交
673 674 675 676 677
{
	sock_hold(sk);
	__sk_add_node(sk, list);
}

E
Eric Dumazet 已提交
678
static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list)
679 680
{
	sock_hold(sk);
681 682 683 684 685
	if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport &&
	    sk->sk_family == AF_INET6)
		hlist_add_tail_rcu(&sk->sk_node, list);
	else
		hlist_add_head_rcu(&sk->sk_node, list);
686 687
}

E
Eric Dumazet 已提交
688
static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
689
{
690
	hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list);
691 692
}

E
Eric Dumazet 已提交
693
static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
694 695
{
	sock_hold(sk);
696
	__sk_nulls_add_node_rcu(sk, list);
697 698
}

E
Eric Dumazet 已提交
699
static inline void __sk_del_bind_node(struct sock *sk)
L
Linus Torvalds 已提交
700 701 702 703
{
	__hlist_del(&sk->sk_bind_node);
}

E
Eric Dumazet 已提交
704
static inline void sk_add_bind_node(struct sock *sk,
L
Linus Torvalds 已提交
705 706 707 708 709
					struct hlist_head *list)
{
	hlist_add_head(&sk->sk_bind_node, list);
}

710 711 712 713
#define sk_for_each(__sk, list) \
	hlist_for_each_entry(__sk, list, sk_node)
#define sk_for_each_rcu(__sk, list) \
	hlist_for_each_entry_rcu(__sk, list, sk_node)
714 715 716 717
#define sk_nulls_for_each(__sk, node, list) \
	hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)
#define sk_nulls_for_each_rcu(__sk, node, list) \
	hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)
718 719
#define sk_for_each_from(__sk) \
	hlist_for_each_entry_from(__sk, sk_node)
720 721 722
#define sk_nulls_for_each_from(__sk, node) \
	if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \
		hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node)
723 724 725 726
#define sk_for_each_safe(__sk, tmp, list) \
	hlist_for_each_entry_safe(__sk, tmp, list, sk_node)
#define sk_for_each_bound(__sk, list) \
	hlist_for_each_entry(__sk, list, sk_bind_node)
L
Linus Torvalds 已提交
727

728
/**
729
 * sk_for_each_entry_offset_rcu - iterate over a list at a given struct offset
730 731 732 733 734 735
 * @tpos:	the type * to use as a loop cursor.
 * @pos:	the &struct hlist_node to use as a loop cursor.
 * @head:	the head for your list.
 * @offset:	offset of hlist_node within the struct.
 *
 */
736
#define sk_for_each_entry_offset_rcu(tpos, pos, head, offset)		       \
737
	for (pos = rcu_dereference(hlist_first_rcu(head));		       \
738
	     pos != NULL &&						       \
739
		({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;});       \
740
	     pos = rcu_dereference(hlist_next_rcu(pos)))
741

E
Eric W. Biederman 已提交
742 743 744 745 746 747 748 749 750
static inline struct user_namespace *sk_user_ns(struct sock *sk)
{
	/* Careful only use this in a context where these parameters
	 * can not change and must all be valid, such as recvmsg from
	 * userspace.
	 */
	return sk->sk_socket->file->f_cred->user_ns;
}

L
Linus Torvalds 已提交
751 752 753 754 755 756 757 758 759 760 761 762 763 764
/* Sock flags */
enum sock_flags {
	SOCK_DEAD,
	SOCK_DONE,
	SOCK_URGINLINE,
	SOCK_KEEPOPEN,
	SOCK_LINGER,
	SOCK_DESTROY,
	SOCK_BROADCAST,
	SOCK_TIMESTAMP,
	SOCK_ZAPPED,
	SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */
	SOCK_DBG, /* %SO_DEBUG setting */
	SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
765
	SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */
L
Linus Torvalds 已提交
766 767
	SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
	SOCK_QUEUE_SHRUNK, /* write queue has been shrunk recently */
768
	SOCK_MEMALLOC, /* VM depends on this socket for swapping */
769
	SOCK_TIMESTAMPING_RX_SOFTWARE,  /* %SOF_TIMESTAMPING_RX_SOFTWARE */
E
Eric Dumazet 已提交
770
	SOCK_FASYNC, /* fasync() active */
771
	SOCK_RXQ_OVFL,
772
	SOCK_ZEROCOPY, /* buffers from userspace */
773
	SOCK_WIFI_STATUS, /* push wifi status to userspace */
774 775 776 777
	SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS.
		     * Will use last 4 bytes of packet sent from
		     * user-space instead.
		     */
778
	SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */
779
	SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */
780
	SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */
L
Linus Torvalds 已提交
781 782
};

783 784
#define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))

R
Ralf Baechle 已提交
785 786 787 788 789
static inline void sock_copy_flags(struct sock *nsk, struct sock *osk)
{
	nsk->sk_flags = osk->sk_flags;
}

L
Linus Torvalds 已提交
790 791 792 793 794 795 796 797 798 799
static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
{
	__set_bit(flag, &sk->sk_flags);
}

static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag)
{
	__clear_bit(flag, &sk->sk_flags);
}

E
Eric Dumazet 已提交
800
static inline bool sock_flag(const struct sock *sk, enum sock_flags flag)
L
Linus Torvalds 已提交
801 802 803 804
{
	return test_bit(flag, &sk->sk_flags);
}

805 806 807 808 809 810 811 812 813 814 815 816 817 818 819
#ifdef CONFIG_NET
extern struct static_key memalloc_socks;
static inline int sk_memalloc_socks(void)
{
	return static_key_false(&memalloc_socks);
}
#else

static inline int sk_memalloc_socks(void)
{
	return 0;
}

#endif

820
static inline gfp_t sk_gfp_mask(const struct sock *sk, gfp_t gfp_mask)
821
{
822
	return gfp_mask | (sk->sk_allocation & __GFP_MEMALLOC);
823 824
}

L
Linus Torvalds 已提交
825 826 827 828 829 830 831 832 833 834
static inline void sk_acceptq_removed(struct sock *sk)
{
	sk->sk_ack_backlog--;
}

static inline void sk_acceptq_added(struct sock *sk)
{
	sk->sk_ack_backlog++;
}

E
Eric Dumazet 已提交
835
static inline bool sk_acceptq_is_full(const struct sock *sk)
L
Linus Torvalds 已提交
836
{
837
	return sk->sk_ack_backlog > sk->sk_max_ack_backlog;
L
Linus Torvalds 已提交
838 839 840 841 842
}

/*
 * Compute minimal free write space needed to queue new packets.
 */
E
Eric Dumazet 已提交
843
static inline int sk_stream_min_wspace(const struct sock *sk)
L
Linus Torvalds 已提交
844
{
845
	return sk->sk_wmem_queued >> 1;
L
Linus Torvalds 已提交
846 847
}

E
Eric Dumazet 已提交
848
static inline int sk_stream_wspace(const struct sock *sk)
L
Linus Torvalds 已提交
849 850 851 852
{
	return sk->sk_sndbuf - sk->sk_wmem_queued;
}

853
void sk_stream_write_space(struct sock *sk);
L
Linus Torvalds 已提交
854

Z
Zhu Yi 已提交
855
/* OOB backlog add */
Z
Zhu Yi 已提交
856
static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
857
{
E
Eric Dumazet 已提交
858
	/* dont let skb dst not refcounted, we are going to leave rcu lock */
E
Eric Dumazet 已提交
859
	skb_dst_force(skb);
E
Eric Dumazet 已提交
860 861 862 863

	if (!sk->sk_backlog.tail)
		sk->sk_backlog.head = skb;
	else
864
		sk->sk_backlog.tail->next = skb;
E
Eric Dumazet 已提交
865 866

	sk->sk_backlog.tail = skb;
867 868
	skb->next = NULL;
}
L
Linus Torvalds 已提交
869

870 871
/*
 * Take into account size of receive queue and backlog queue
E
Eric Dumazet 已提交
872 873
 * Do not take into account this skb truesize,
 * to allow even a single big packet to come.
874
 */
875
static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit)
876 877 878
{
	unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc);

879
	return qsize > limit;
880 881
}

Z
Zhu Yi 已提交
882
/* The per-socket spinlock must be held here. */
883 884
static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb,
					      unsigned int limit)
Z
Zhu Yi 已提交
885
{
886
	if (sk_rcvqueues_full(sk, limit))
Z
Zhu Yi 已提交
887 888
		return -ENOBUFS;

889 890 891 892 893 894 895 896
	/*
	 * If the skb was allocated from pfmemalloc reserves, only
	 * allow SOCK_MEMALLOC sockets to use it as this socket is
	 * helping free memory
	 */
	if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC))
		return -ENOMEM;

Z
Zhu Yi 已提交
897
	__sk_add_backlog(sk, skb);
Z
Zhu Yi 已提交
898 899 900 901
	sk->sk_backlog.len += skb->truesize;
	return 0;
}

902
int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb);
903

P
Peter Zijlstra 已提交
904 905
static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
{
906 907 908
	if (sk_memalloc_socks() && skb_pfmemalloc(skb))
		return __sk_backlog_rcv(sk, skb);

P
Peter Zijlstra 已提交
909 910 911
	return sk->sk_backlog_rcv(sk, skb);
}

E
Eric Dumazet 已提交
912 913
static inline void sk_incoming_cpu_update(struct sock *sk)
{
914 915 916 917
	int cpu = raw_smp_processor_id();

	if (unlikely(sk->sk_incoming_cpu != cpu))
		sk->sk_incoming_cpu = cpu;
E
Eric Dumazet 已提交
918 919
}

920
static inline void sock_rps_record_flow_hash(__u32 hash)
921 922 923 924 925 926
{
#ifdef CONFIG_RPS
	struct rps_sock_flow_table *sock_flow_table;

	rcu_read_lock();
	sock_flow_table = rcu_dereference(rps_sock_flow_table);
927
	rps_record_sock_flow(sock_flow_table, hash);
928 929 930 931
	rcu_read_unlock();
#endif
}

932 933
static inline void sock_rps_record_flow(const struct sock *sk)
{
934
#ifdef CONFIG_RPS
E
Eric Dumazet 已提交
935 936 937 938 939 940 941 942 943 944 945 946 947 948
	if (static_key_false(&rfs_needed)) {
		/* Reading sk->sk_rxhash might incur an expensive cache line
		 * miss.
		 *
		 * TCP_ESTABLISHED does cover almost all states where RFS
		 * might be useful, and is cheaper [1] than testing :
		 *	IPv4: inet_sk(sk)->inet_daddr
		 * 	IPv6: ipv6_addr_any(&sk->sk_v6_daddr)
		 * OR	an additional socket flag
		 * [1] : sk_state and sk_prot are in the same cache line.
		 */
		if (sk->sk_state == TCP_ESTABLISHED)
			sock_rps_record_flow_hash(sk->sk_rxhash);
	}
949
#endif
950 951
}

952 953
static inline void sock_rps_save_rxhash(struct sock *sk,
					const struct sk_buff *skb)
954 955
{
#ifdef CONFIG_RPS
956
	if (unlikely(sk->sk_rxhash != skb->hash))
957
		sk->sk_rxhash = skb->hash;
958 959 960
#endif
}

961 962 963 964 965 966 967
static inline void sock_rps_reset_rxhash(struct sock *sk)
{
#ifdef CONFIG_RPS
	sk->sk_rxhash = 0;
#endif
}

W
WANG Cong 已提交
968
#define sk_wait_event(__sk, __timeo, __condition, __wait)		\
S
Stephen Hemminger 已提交
969 970 971 972
	({	int __rc;						\
		release_sock(__sk);					\
		__rc = __condition;					\
		if (!__rc) {						\
W
WANG Cong 已提交
973 974 975
			*(__timeo) = wait_woken(__wait,			\
						TASK_INTERRUPTIBLE,	\
						*(__timeo));		\
S
Stephen Hemminger 已提交
976
		}							\
W
WANG Cong 已提交
977
		sched_annotate_sleep();					\
S
Stephen Hemminger 已提交
978 979 980 981
		lock_sock(__sk);					\
		__rc = __condition;					\
		__rc;							\
	})
L
Linus Torvalds 已提交
982

983 984 985 986 987 988 989
int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
void sk_stream_wait_close(struct sock *sk, long timeo_p);
int sk_stream_error(struct sock *sk, int flags, int err);
void sk_stream_kill_queues(struct sock *sk);
void sk_set_memalloc(struct sock *sk);
void sk_clear_memalloc(struct sock *sk);
L
Linus Torvalds 已提交
990

991 992 993 994 995 996 997 998 999 1000 1001
void __sk_flush_backlog(struct sock *sk);

static inline bool sk_flush_backlog(struct sock *sk)
{
	if (unlikely(READ_ONCE(sk->sk_backlog.tail))) {
		__sk_flush_backlog(sk);
		return true;
	}
	return false;
}

1002
int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb);
L
Linus Torvalds 已提交
1003

1004
struct request_sock_ops;
1005
struct timewait_sock_ops;
1006
struct inet_hashinfo;
1007
struct raw_hashinfo;
1008
struct smc_hashinfo;
1009
struct module;
1010

E
Eric Dumazet 已提交
1011
/*
1012
 * caches using SLAB_TYPESAFE_BY_RCU should let .next pointer from nulls nodes
E
Eric Dumazet 已提交
1013 1014 1015 1016 1017 1018 1019 1020 1021 1022
 * un-modified. Special care is taken when initializing object to zero.
 */
static inline void sk_prot_clear_nulls(struct sock *sk, int size)
{
	if (offsetof(struct sock, sk_node.next) != 0)
		memset(sk, 0, offsetof(struct sock, sk_node.next));
	memset(&sk->sk_node.pprev, 0,
	       size - offsetof(struct sock, sk_node.pprev));
}

L
Linus Torvalds 已提交
1023 1024 1025 1026
/* Networking protocol blocks we attach to sockets.
 * socket layer -> transport layer interface
 */
struct proto {
E
Eric Dumazet 已提交
1027
	void			(*close)(struct sock *sk,
L
Linus Torvalds 已提交
1028 1029
					long timeout);
	int			(*connect)(struct sock *sk,
E
Eric Dumazet 已提交
1030
					struct sockaddr *uaddr,
L
Linus Torvalds 已提交
1031 1032 1033
					int addr_len);
	int			(*disconnect)(struct sock *sk, int flags);

1034 1035
	struct sock *		(*accept)(struct sock *sk, int flags, int *err,
					  bool kern);
L
Linus Torvalds 已提交
1036 1037 1038 1039

	int			(*ioctl)(struct sock *sk, int cmd,
					 unsigned long arg);
	int			(*init)(struct sock *sk);
1040
	void			(*destroy)(struct sock *sk);
L
Linus Torvalds 已提交
1041
	void			(*shutdown)(struct sock *sk, int how);
E
Eric Dumazet 已提交
1042
	int			(*setsockopt)(struct sock *sk, int level,
L
Linus Torvalds 已提交
1043
					int optname, char __user *optval,
1044
					unsigned int optlen);
E
Eric Dumazet 已提交
1045 1046 1047
	int			(*getsockopt)(struct sock *sk, int level,
					int optname, char __user *optval,
					int __user *option);
1048
	void			(*keepalive)(struct sock *sk, int valbool);
A
Alexey Dobriyan 已提交
1049
#ifdef CONFIG_COMPAT
1050 1051 1052
	int			(*compat_setsockopt)(struct sock *sk,
					int level,
					int optname, char __user *optval,
1053
					unsigned int optlen);
1054 1055 1056 1057
	int			(*compat_getsockopt)(struct sock *sk,
					int level,
					int optname, char __user *optval,
					int __user *option);
1058 1059
	int			(*compat_ioctl)(struct sock *sk,
					unsigned int cmd, unsigned long arg);
A
Alexey Dobriyan 已提交
1060
#endif
1061 1062 1063
	int			(*sendmsg)(struct sock *sk, struct msghdr *msg,
					   size_t len);
	int			(*recvmsg)(struct sock *sk, struct msghdr *msg,
E
Eric Dumazet 已提交
1064 1065
					   size_t len, int noblock, int flags,
					   int *addr_len);
L
Linus Torvalds 已提交
1066 1067
	int			(*sendpage)(struct sock *sk, struct page *page,
					int offset, size_t size, int flags);
E
Eric Dumazet 已提交
1068
	int			(*bind)(struct sock *sk,
L
Linus Torvalds 已提交
1069 1070
					struct sockaddr *uaddr, int addr_len);

E
Eric Dumazet 已提交
1071
	int			(*backlog_rcv) (struct sock *sk,
L
Linus Torvalds 已提交
1072 1073
						struct sk_buff *skb);

E
Eric Dumazet 已提交
1074 1075
	void		(*release_cb)(struct sock *sk);

L
Linus Torvalds 已提交
1076
	/* Keeping track of sk's, looking them up, and port selection methods. */
1077
	int			(*hash)(struct sock *sk);
L
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1078
	void			(*unhash)(struct sock *sk);
E
Eric Dumazet 已提交
1079
	void			(*rehash)(struct sock *sk);
L
Linus Torvalds 已提交
1080 1081
	int			(*get_port)(struct sock *sk, unsigned short snum);

1082
	/* Keeping track of sockets in use */
1083
#ifdef CONFIG_PROC_FS
1084
	unsigned int		inuse_idx;
1085
#endif
1086

1087
	bool			(*stream_memory_free)(const struct sock *sk);
1088
	bool			(*stream_memory_read)(const struct sock *sk);
L
Linus Torvalds 已提交
1089
	/* Memory pressure */
1090
	void			(*enter_memory_pressure)(struct sock *sk);
1091
	void			(*leave_memory_pressure)(struct sock *sk);
E
Eric Dumazet 已提交
1092
	atomic_long_t		*memory_allocated;	/* Current allocated memory. */
1093
	struct percpu_counter	*sockets_allocated;	/* Current number of sockets. */
L
Linus Torvalds 已提交
1094 1095 1096
	/*
	 * Pressure flag: try to collapse.
	 * Technical note: it is used by multiple contexts non atomically.
1097
	 * All the __sk_mem_schedule() is of this nature: accounting
L
Linus Torvalds 已提交
1098 1099
	 * is strict, actions are advisory and have some latency.
	 */
1100
	unsigned long		*memory_pressure;
E
Eric Dumazet 已提交
1101
	long			*sysctl_mem;
1102

L
Linus Torvalds 已提交
1103 1104
	int			*sysctl_wmem;
	int			*sysctl_rmem;
1105 1106 1107
	u32			sysctl_wmem_offset;
	u32			sysctl_rmem_offset;

L
Linus Torvalds 已提交
1108
	int			max_header;
1109
	bool			no_autobind;
L
Linus Torvalds 已提交
1110

1111
	struct kmem_cache	*slab;
L
Linus Torvalds 已提交
1112
	unsigned int		obj_size;
1113
	slab_flags_t		slab_flags;
1114 1115
	size_t			useroffset;	/* Usercopy region offset */
	size_t			usersize;	/* Usercopy region size */
L
Linus Torvalds 已提交
1116

1117
	struct percpu_counter	*orphan_count;
1118

1119
	struct request_sock_ops	*rsk_prot;
1120
	struct timewait_sock_ops *twsk_prot;
1121

1122 1123
	union {
		struct inet_hashinfo	*hashinfo;
1124
		struct udp_table	*udp_table;
1125
		struct raw_hashinfo	*raw_hash;
1126
		struct smc_hashinfo	*smc_hash;
1127
	} h;
1128

L
Linus Torvalds 已提交
1129 1130 1131 1132 1133
	struct module		*owner;

	char			name[32];

	struct list_head	node;
1134 1135
#ifdef SOCK_REFCNT_DEBUG
	atomic_t		socks;
G
Glauber Costa 已提交
1136
#endif
1137
	int			(*diag_destroy)(struct sock *sk, int err);
1138
} __randomize_layout;
G
Glauber Costa 已提交
1139

1140 1141
int proto_register(struct proto *prot, int alloc_slab);
void proto_unregister(struct proto *prot);
1142
int sock_load_diag_module(int family, int protocol);
L
Linus Torvalds 已提交
1143

1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156
#ifdef SOCK_REFCNT_DEBUG
static inline void sk_refcnt_debug_inc(struct sock *sk)
{
	atomic_inc(&sk->sk_prot->socks);
}

static inline void sk_refcnt_debug_dec(struct sock *sk)
{
	atomic_dec(&sk->sk_prot->socks);
	printk(KERN_DEBUG "%s socket %p released, %d are still alive\n",
	       sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks));
}

1157
static inline void sk_refcnt_debug_release(const struct sock *sk)
1158
{
1159
	if (refcount_read(&sk->sk_refcnt) != 1)
1160
		printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n",
1161
		       sk->sk_prot->name, sk, refcount_read(&sk->sk_refcnt));
1162 1163 1164 1165 1166 1167 1168
}
#else /* SOCK_REFCNT_DEBUG */
#define sk_refcnt_debug_inc(sk) do { } while (0)
#define sk_refcnt_debug_dec(sk) do { } while (0)
#define sk_refcnt_debug_release(sk) do { } while (0)
#endif /* SOCK_REFCNT_DEBUG */

1169 1170 1171 1172 1173 1174 1175 1176 1177
static inline bool sk_stream_memory_free(const struct sock *sk)
{
	if (sk->sk_wmem_queued >= sk->sk_sndbuf)
		return false;

	return sk->sk_prot->stream_memory_free ?
		sk->sk_prot->stream_memory_free(sk) : true;
}

1178 1179
static inline bool sk_stream_is_writeable(const struct sock *sk)
{
1180 1181
	return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) &&
	       sk_stream_memory_free(sk);
1182
}
G
Glauber Costa 已提交
1183

1184 1185 1186 1187 1188 1189 1190 1191 1192 1193
static inline int sk_under_cgroup_hierarchy(struct sock *sk,
					    struct cgroup *ancestor)
{
#ifdef CONFIG_SOCK_CGROUP_DATA
	return cgroup_is_descendant(sock_cgroup_ptr(&sk->sk_cgrp_data),
				    ancestor);
#else
	return -ENOTSUPP;
#endif
}
1194

1195 1196 1197 1198 1199 1200 1201 1202 1203
static inline bool sk_has_memory_pressure(const struct sock *sk)
{
	return sk->sk_prot->memory_pressure != NULL;
}

static inline bool sk_under_memory_pressure(const struct sock *sk)
{
	if (!sk->sk_prot->memory_pressure)
		return false;
G
Glauber Costa 已提交
1204

1205 1206
	if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
	    mem_cgroup_under_socket_pressure(sk->sk_memcg))
1207
		return true;
G
Glauber Costa 已提交
1208

1209
	return !!*sk->sk_prot->memory_pressure;
1210 1211 1212 1213 1214
}

static inline long
sk_memory_allocated(const struct sock *sk)
{
1215
	return atomic_long_read(sk->sk_prot->memory_allocated);
1216 1217 1218
}

static inline long
1219
sk_memory_allocated_add(struct sock *sk, int amt)
1220
{
1221
	return atomic_long_add_return(amt, sk->sk_prot->memory_allocated);
1222 1223 1224
}

static inline void
1225
sk_memory_allocated_sub(struct sock *sk, int amt)
1226
{
1227
	atomic_long_sub(amt, sk->sk_prot->memory_allocated);
1228 1229 1230 1231
}

static inline void sk_sockets_allocated_dec(struct sock *sk)
{
1232
	percpu_counter_dec(sk->sk_prot->sockets_allocated);
1233 1234 1235 1236
}

static inline void sk_sockets_allocated_inc(struct sock *sk)
{
1237
	percpu_counter_inc(sk->sk_prot->sockets_allocated);
1238 1239 1240 1241 1242
}

static inline int
sk_sockets_allocated_read_positive(struct sock *sk)
{
1243
	return percpu_counter_read_positive(sk->sk_prot->sockets_allocated);
1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265
}

static inline int
proto_sockets_allocated_sum_positive(struct proto *prot)
{
	return percpu_counter_sum_positive(prot->sockets_allocated);
}

static inline long
proto_memory_allocated(struct proto *prot)
{
	return atomic_long_read(prot->memory_allocated);
}

static inline bool
proto_memory_pressure(struct proto *prot)
{
	if (!prot->memory_pressure)
		return false;
	return !!*prot->memory_pressure;
}

1266 1267

#ifdef CONFIG_PROC_FS
L
Linus Torvalds 已提交
1268
/* Called with local bh disabled */
1269 1270
void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc);
int sock_prot_inuse_get(struct net *net, struct proto *proto);
1271
int sock_inuse_get(struct net *net);
1272
#else
E
Eric Dumazet 已提交
1273
static inline void sock_prot_inuse_add(struct net *net, struct proto *prot,
1274
		int inc)
1275 1276 1277 1278
{
}
#endif

L
Linus Torvalds 已提交
1279

1280 1281 1282
/* With per-bucket locks this operation is not-atomic, so that
 * this version is not worse.
 */
1283
static inline int __sk_prot_rehash(struct sock *sk)
1284 1285
{
	sk->sk_prot->unhash(sk);
1286
	return sk->sk_prot->hash(sk);
1287 1288
}

L
Linus Torvalds 已提交
1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318
/* About 10 seconds */
#define SOCK_DESTROY_TIME (10*HZ)

/* Sockets 0-1023 can't be bound to unless you are superuser */
#define PROT_SOCK	1024

#define SHUTDOWN_MASK	3
#define RCV_SHUTDOWN	1
#define SEND_SHUTDOWN	2

#define SOCK_SNDBUF_LOCK	1
#define SOCK_RCVBUF_LOCK	2
#define SOCK_BINDADDR_LOCK	4
#define SOCK_BINDPORT_LOCK	8

struct socket_alloc {
	struct socket socket;
	struct inode vfs_inode;
};

static inline struct socket *SOCKET_I(struct inode *inode)
{
	return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
}

static inline struct inode *SOCK_INODE(struct socket *socket)
{
	return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
}

1319 1320 1321
/*
 * Functions for memory accounting
 */
1322
int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind);
1323
int __sk_mem_schedule(struct sock *sk, int size, int kind);
1324
void __sk_mem_reduce_allocated(struct sock *sk, int amount);
E
Eric Dumazet 已提交
1325
void __sk_mem_reclaim(struct sock *sk, int amount);
L
Linus Torvalds 已提交
1326

E
Eric Dumazet 已提交
1327 1328 1329 1330
/* We used to have PAGE_SIZE here, but systems with 64KB pages
 * do not necessarily have 16x time more memory than 4KB ones.
 */
#define SK_MEM_QUANTUM 4096
1331 1332 1333
#define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM)
#define SK_MEM_SEND	0
#define SK_MEM_RECV	1
L
Linus Torvalds 已提交
1334

E
Eric Dumazet 已提交
1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347
/* sysctl_mem values are in pages, we convert them in SK_MEM_QUANTUM units */
static inline long sk_prot_mem_limits(const struct sock *sk, int index)
{
	long val = sk->sk_prot->sysctl_mem[index];

#if PAGE_SIZE > SK_MEM_QUANTUM
	val <<= PAGE_SHIFT - SK_MEM_QUANTUM_SHIFT;
#elif PAGE_SIZE < SK_MEM_QUANTUM
	val >>= SK_MEM_QUANTUM_SHIFT - PAGE_SHIFT;
#endif
	return val;
}

1348
static inline int sk_mem_pages(int amt)
L
Linus Torvalds 已提交
1349
{
1350
	return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT;
L
Linus Torvalds 已提交
1351 1352
}

E
Eric Dumazet 已提交
1353
static inline bool sk_has_account(struct sock *sk)
L
Linus Torvalds 已提交
1354
{
1355 1356
	/* return true if protocol supports memory accounting */
	return !!sk->sk_prot->memory_allocated;
L
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1357 1358
}

E
Eric Dumazet 已提交
1359
static inline bool sk_wmem_schedule(struct sock *sk, int size)
L
Linus Torvalds 已提交
1360
{
1361
	if (!sk_has_account(sk))
E
Eric Dumazet 已提交
1362
		return true;
1363 1364
	return size <= sk->sk_forward_alloc ||
		__sk_mem_schedule(sk, size, SK_MEM_SEND);
L
Linus Torvalds 已提交
1365 1366
}

1367
static inline bool
1368
sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size)
H
Herbert Xu 已提交
1369
{
1370
	if (!sk_has_account(sk))
E
Eric Dumazet 已提交
1371
		return true;
1372 1373 1374
	return size<= sk->sk_forward_alloc ||
		__sk_mem_schedule(sk, size, SK_MEM_RECV) ||
		skb_pfmemalloc(skb);
1375 1376 1377 1378 1379 1380 1381
}

static inline void sk_mem_reclaim(struct sock *sk)
{
	if (!sk_has_account(sk))
		return;
	if (sk->sk_forward_alloc >= SK_MEM_QUANTUM)
E
Eric Dumazet 已提交
1382
		__sk_mem_reclaim(sk, sk->sk_forward_alloc);
1383 1384
}

1385 1386 1387 1388 1389
static inline void sk_mem_reclaim_partial(struct sock *sk)
{
	if (!sk_has_account(sk))
		return;
	if (sk->sk_forward_alloc > SK_MEM_QUANTUM)
E
Eric Dumazet 已提交
1390
		__sk_mem_reclaim(sk, sk->sk_forward_alloc - 1);
1391 1392
}

1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404
static inline void sk_mem_charge(struct sock *sk, int size)
{
	if (!sk_has_account(sk))
		return;
	sk->sk_forward_alloc -= size;
}

static inline void sk_mem_uncharge(struct sock *sk, int size)
{
	if (!sk_has_account(sk))
		return;
	sk->sk_forward_alloc += size;
1405 1406 1407 1408 1409 1410 1411 1412 1413 1414

	/* Avoid a possible overflow.
	 * TCP send queues can make this happen, if sk_mem_reclaim()
	 * is not called and more than 2 GBytes are released at once.
	 *
	 * If we reach 2 MBytes, reclaim 1 MBytes right now, there is
	 * no need to hold that much forward allocation anyway.
	 */
	if (unlikely(sk->sk_forward_alloc >= 1 << 21))
		__sk_mem_reclaim(sk, 1 << 20);
1415 1416 1417 1418 1419 1420 1421 1422
}

static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb)
{
	sock_set_flag(sk, SOCK_QUEUE_SHRUNK);
	sk->sk_wmem_queued -= skb->truesize;
	sk_mem_uncharge(sk, skb->truesize);
	__kfree_skb(skb);
H
Herbert Xu 已提交
1423 1424
}

1425 1426
static inline void sock_release_ownership(struct sock *sk)
{
1427 1428 1429 1430 1431 1432
	if (sk->sk_lock.owned) {
		sk->sk_lock.owned = 0;

		/* The sk_lock has mutex_unlock() semantics: */
		mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
	}
1433 1434
}

1435 1436 1437 1438 1439 1440 1441
/*
 * Macro so as to not evaluate some arguments when
 * lockdep is not enabled.
 *
 * Mark both the sk_lock and the sk_lock.slock as a
 * per-address-family lock class.
 */
E
Eric Dumazet 已提交
1442
#define sock_lock_init_class_and_name(sk, sname, skey, name, key)	\
1443
do {									\
1444
	sk->sk_lock.owned = 0;						\
1445 1446 1447 1448 1449
	init_waitqueue_head(&sk->sk_lock.wq);				\
	spin_lock_init(&(sk)->sk_lock.slock);				\
	debug_check_no_locks_freed((void *)&(sk)->sk_lock,		\
			sizeof((sk)->sk_lock));				\
	lockdep_set_class_and_name(&(sk)->sk_lock.slock,		\
E
Eric Dumazet 已提交
1450
				(skey), (sname));				\
1451 1452 1453
	lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0);	\
} while (0)

1454
#ifdef CONFIG_LOCKDEP
1455
static inline bool lockdep_sock_is_held(const struct sock *sk)
1456 1457 1458 1459
{
	return lockdep_is_held(&sk->sk_lock) ||
	       lockdep_is_held(&sk->sk_lock.slock);
}
1460
#endif
1461

1462
void lock_sock_nested(struct sock *sk, int subclass);
1463 1464 1465 1466 1467 1468

static inline void lock_sock(struct sock *sk)
{
	lock_sock_nested(sk, 0);
}

1469
void release_sock(struct sock *sk);
L
Linus Torvalds 已提交
1470 1471 1472

/* BH context may only use the following locking interface. */
#define bh_lock_sock(__sk)	spin_lock(&((__sk)->sk_lock.slock))
1473 1474 1475
#define bh_lock_sock_nested(__sk) \
				spin_lock_nested(&((__sk)->sk_lock.slock), \
				SINGLE_DEPTH_NESTING)
L
Linus Torvalds 已提交
1476 1477
#define bh_unlock_sock(__sk)	spin_unlock(&((__sk)->sk_lock.slock))

1478
bool lock_sock_fast(struct sock *sk);
1479 1480 1481 1482 1483 1484 1485 1486 1487
/**
 * unlock_sock_fast - complement of lock_sock_fast
 * @sk: socket
 * @slow: slow mode
 *
 * fast unlock socket for user context.
 * If slow mode is on, we call regular release_sock()
 */
static inline void unlock_sock_fast(struct sock *sk, bool slow)
E
Eric Dumazet 已提交
1488
{
1489 1490 1491 1492
	if (slow)
		release_sock(sk);
	else
		spin_unlock_bh(&sk->sk_lock.slock);
E
Eric Dumazet 已提交
1493 1494
}

1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508
/* Used by processes to "lock" a socket state, so that
 * interrupts and bottom half handlers won't change it
 * from under us. It essentially blocks any incoming
 * packets, so that we won't get any new data or any
 * packets that change the state of the socket.
 *
 * While locked, BH processing will add new packets to
 * the backlog queue.  This queue is processed by the
 * owner of the socket lock right before it is released.
 *
 * Since ~2.3.5 it is also exclusive sleep lock serializing
 * accesses from user process context.
 */

1509
static inline void sock_owned_by_me(const struct sock *sk)
1510 1511
{
#ifdef CONFIG_LOCKDEP
1512
	WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks);
1513
#endif
1514 1515 1516 1517 1518
}

static inline bool sock_owned_by_user(const struct sock *sk)
{
	sock_owned_by_me(sk);
1519 1520 1521
	return sk->sk_lock.owned;
}

T
Tom Herbert 已提交
1522 1523 1524 1525 1526
static inline bool sock_owned_by_user_nocheck(const struct sock *sk)
{
	return sk->sk_lock.owned;
}

1527 1528 1529 1530 1531 1532 1533
/* no reclassification while locks are held */
static inline bool sock_allow_reclassification(const struct sock *csk)
{
	struct sock *sk = (struct sock *)csk;

	return !sk->sk_lock.owned && !spin_is_locked(&sk->sk_lock.slock);
}
E
Eric Dumazet 已提交
1534

1535
struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1536
		      struct proto *prot, int kern);
1537
void sk_free(struct sock *sk);
1538
void sk_destruct(struct sock *sk);
1539
struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority);
1540
void sk_free_unlock_clone(struct sock *sk);
1541 1542 1543

struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
			     gfp_t priority);
E
Eric Dumazet 已提交
1544
void __sock_wfree(struct sk_buff *skb);
1545
void sock_wfree(struct sk_buff *skb);
1546 1547
struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
			     gfp_t priority);
1548 1549
void skb_orphan_partial(struct sk_buff *skb);
void sock_rfree(struct sk_buff *skb);
1550
void sock_efree(struct sk_buff *skb);
1551
#ifdef CONFIG_INET
1552
void sock_edemux(struct sk_buff *skb);
1553
#else
1554
#define sock_edemux sock_efree
1555
#endif
1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568

int sock_setsockopt(struct socket *sock, int level, int op,
		    char __user *optval, unsigned int optlen);

int sock_getsockopt(struct socket *sock, int level, int op,
		    char __user *optval, int __user *optlen);
struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
				    int noblock, int *errcode);
struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
				     unsigned long data_len, int noblock,
				     int *errcode, int max_page_order);
void *sock_kmalloc(struct sock *sk, int size, gfp_t priority);
void sock_kfree_s(struct sock *sk, void *mem, int size);
1569
void sock_kzfree_s(struct sock *sk, void *mem, int size);
1570
void sk_send_sigurg(struct sock *sk);
L
Linus Torvalds 已提交
1571

E
Edward Jee 已提交
1572 1573
struct sockcm_cookie {
	u32 mark;
1574
	u16 tsflags;
E
Edward Jee 已提交
1575 1576
};

1577 1578
int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg,
		     struct sockcm_cookie *sockc);
E
Edward Jee 已提交
1579 1580 1581
int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
		   struct sockcm_cookie *sockc);

L
Linus Torvalds 已提交
1582 1583 1584 1585
/*
 * Functions to fill in entries in struct proto_ops when a protocol
 * does not implement a particular function.
 */
1586 1587 1588
int sock_no_bind(struct socket *, struct sockaddr *, int);
int sock_no_connect(struct socket *, struct sockaddr *, int, int);
int sock_no_socketpair(struct socket *, struct socket *);
1589
int sock_no_accept(struct socket *, struct socket *, int, bool);
1590
int sock_no_getname(struct socket *, struct sockaddr *, int);
A
Al Viro 已提交
1591
__poll_t sock_no_poll(struct file *, struct socket *,
1592 1593 1594 1595 1596 1597
			  struct poll_table_struct *);
int sock_no_ioctl(struct socket *, unsigned int, unsigned long);
int sock_no_listen(struct socket *, int);
int sock_no_shutdown(struct socket *, int);
int sock_no_getsockopt(struct socket *, int , int, char __user *, int __user *);
int sock_no_setsockopt(struct socket *, int, int, char __user *, unsigned int);
1598
int sock_no_sendmsg(struct socket *, struct msghdr *, size_t);
1599
int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len);
1600
int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int);
1601 1602 1603 1604
int sock_no_mmap(struct file *file, struct socket *sock,
		 struct vm_area_struct *vma);
ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset,
			 size_t size, int flags);
1605 1606
ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
				int offset, size_t size, int flags);
L
Linus Torvalds 已提交
1607 1608 1609 1610 1611

/*
 * Functions to fill in entries in struct proto_ops when a protocol
 * uses the inet style.
 */
1612
int sock_common_getsockopt(struct socket *sock, int level, int optname,
L
Linus Torvalds 已提交
1613
				  char __user *optval, int __user *optlen);
1614 1615
int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
			int flags);
1616
int sock_common_setsockopt(struct socket *sock, int level, int optname,
1617
				  char __user *optval, unsigned int optlen);
1618
int compat_sock_common_getsockopt(struct socket *sock, int level,
1619
		int optname, char __user *optval, int __user *optlen);
1620
int compat_sock_common_setsockopt(struct socket *sock, int level,
1621
		int optname, char __user *optval, unsigned int optlen);
L
Linus Torvalds 已提交
1622

1623
void sk_common_release(struct sock *sk);
L
Linus Torvalds 已提交
1624 1625 1626 1627

/*
 *	Default socket callbacks and setup code
 */
E
Eric Dumazet 已提交
1628

L
Linus Torvalds 已提交
1629
/* Initialise core socket variables */
1630
void sock_init_data(struct socket *sock, struct sock *sk);
L
Linus Torvalds 已提交
1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659

/*
 * Socket reference counting postulates.
 *
 * * Each user of socket SHOULD hold a reference count.
 * * Each access point to socket (an hash table bucket, reference from a list,
 *   running timer, skb in flight MUST hold a reference count.
 * * When reference count hits 0, it means it will never increase back.
 * * When reference count hits 0, it means that no references from
 *   outside exist to this socket and current process on current CPU
 *   is last user and may/should destroy this socket.
 * * sk_free is called from any context: process, BH, IRQ. When
 *   it is called, socket has no references from outside -> sk_free
 *   may release descendant resources allocated by the socket, but
 *   to the time when it is called, socket is NOT referenced by any
 *   hash tables, lists etc.
 * * Packets, delivered from outside (from network or from another process)
 *   and enqueued on receive/error queues SHOULD NOT grab reference count,
 *   when they sit in queue. Otherwise, packets will leak to hole, when
 *   socket is looked up by one cpu and unhasing is made by another CPU.
 *   It is true for udp/raw, netlink (leak to receive and error queues), tcp
 *   (leak to backlog). Packet socket does all the processing inside
 *   BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
 *   use separate SMP lock, so that they are prone too.
 */

/* Ungrab socket and destroy it, if it was the last reference. */
static inline void sock_put(struct sock *sk)
{
1660
	if (refcount_dec_and_test(&sk->sk_refcnt))
L
Linus Torvalds 已提交
1661 1662
		sk_free(sk);
}
E
Eric Dumazet 已提交
1663
/* Generic version of sock_put(), dealing with all sockets
1664
 * (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...)
E
Eric Dumazet 已提交
1665 1666
 */
void sock_gen_put(struct sock *sk);
L
Linus Torvalds 已提交
1667

1668
int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested,
1669
		     unsigned int trim_cap, bool refcounted);
1670 1671 1672
static inline int sk_receive_skb(struct sock *sk, struct sk_buff *skb,
				 const int nested)
{
1673
	return __sk_receive_skb(sk, skb, nested, 1, true);
1674
}
1675

K
Krishna Kumar 已提交
1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687
static inline void sk_tx_queue_set(struct sock *sk, int tx_queue)
{
	sk->sk_tx_queue_mapping = tx_queue;
}

static inline void sk_tx_queue_clear(struct sock *sk)
{
	sk->sk_tx_queue_mapping = -1;
}

static inline int sk_tx_queue_get(const struct sock *sk)
{
1688
	return sk ? sk->sk_tx_queue_mapping : -1;
K
Krishna Kumar 已提交
1689 1690
}

1691 1692
static inline void sk_set_socket(struct sock *sk, struct socket *sock)
{
K
Krishna Kumar 已提交
1693
	sk_tx_queue_clear(sk);
1694 1695 1696
	sk->sk_socket = sock;
}

E
Eric Dumazet 已提交
1697 1698
static inline wait_queue_head_t *sk_sleep(struct sock *sk)
{
1699 1700
	BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0);
	return &rcu_dereference_raw(sk->sk_wq)->wait;
E
Eric Dumazet 已提交
1701
}
L
Linus Torvalds 已提交
1702 1703 1704 1705 1706 1707 1708 1709 1710 1711 1712
/* Detach socket from process context.
 * Announce socket dead, detach it from wait queue and inode.
 * Note that parent inode held reference count on this struct sock,
 * we do not release it in this function, because protocol
 * probably wants some additional cleanups or even continuing
 * to work with this socket (TCP).
 */
static inline void sock_orphan(struct sock *sk)
{
	write_lock_bh(&sk->sk_callback_lock);
	sock_set_flag(sk, SOCK_DEAD);
1713
	sk_set_socket(sk, NULL);
1714
	sk->sk_wq  = NULL;
L
Linus Torvalds 已提交
1715 1716 1717 1718 1719
	write_unlock_bh(&sk->sk_callback_lock);
}

static inline void sock_graft(struct sock *sk, struct socket *parent)
{
1720
	WARN_ON(parent->sk);
L
Linus Torvalds 已提交
1721
	write_lock_bh(&sk->sk_callback_lock);
1722
	sk->sk_wq = parent->wq;
L
Linus Torvalds 已提交
1723
	parent->sk = sk;
1724
	sk_set_socket(sk, parent);
1725
	sk->sk_uid = SOCK_INODE(parent)->i_uid;
1726
	security_sock_graft(sk, parent);
L
Linus Torvalds 已提交
1727 1728 1729
	write_unlock_bh(&sk->sk_callback_lock);
}

1730 1731
kuid_t sock_i_uid(struct sock *sk);
unsigned long sock_i_ino(struct sock *sk);
L
Linus Torvalds 已提交
1732

1733 1734 1735 1736 1737
static inline kuid_t sock_net_uid(const struct net *net, const struct sock *sk)
{
	return sk ? sk->sk_uid : make_kuid(net->user_ns, 0);
}

1738
static inline u32 net_tx_rndhash(void)
1739
{
1740 1741 1742 1743
	u32 v = prandom_u32();

	return v ?: 1;
}
1744

1745 1746 1747
static inline void sk_set_txhash(struct sock *sk)
{
	sk->sk_txhash = net_tx_rndhash();
1748 1749
}

1750 1751 1752 1753 1754 1755
static inline void sk_rethink_txhash(struct sock *sk)
{
	if (sk->sk_txhash)
		sk_set_txhash(sk);
}

L
Linus Torvalds 已提交
1756 1757 1758
static inline struct dst_entry *
__sk_dst_get(struct sock *sk)
{
1759 1760
	return rcu_dereference_check(sk->sk_dst_cache,
				     lockdep_sock_is_held(sk));
L
Linus Torvalds 已提交
1761 1762 1763 1764 1765 1766 1767
}

static inline struct dst_entry *
sk_dst_get(struct sock *sk)
{
	struct dst_entry *dst;

E
Eric Dumazet 已提交
1768 1769
	rcu_read_lock();
	dst = rcu_dereference(sk->sk_dst_cache);
1770 1771
	if (dst && !atomic_inc_not_zero(&dst->__refcnt))
		dst = NULL;
E
Eric Dumazet 已提交
1772
	rcu_read_unlock();
L
Linus Torvalds 已提交
1773 1774 1775
	return dst;
}

E
Eric Dumazet 已提交
1776 1777 1778 1779
static inline void dst_negative_advice(struct sock *sk)
{
	struct dst_entry *ndst, *dst = __sk_dst_get(sk);

1780 1781
	sk_rethink_txhash(sk);

E
Eric Dumazet 已提交
1782 1783 1784 1785 1786
	if (dst && dst->ops->negative_advice) {
		ndst = dst->ops->negative_advice(dst);

		if (ndst != dst) {
			rcu_assign_pointer(sk->sk_dst_cache, ndst);
Z
ZHAO Gang 已提交
1787
			sk_tx_queue_clear(sk);
1788
			sk->sk_dst_pending_confirm = 0;
E
Eric Dumazet 已提交
1789 1790 1791 1792
		}
	}
}

L
Linus Torvalds 已提交
1793 1794 1795 1796 1797
static inline void
__sk_dst_set(struct sock *sk, struct dst_entry *dst)
{
	struct dst_entry *old_dst;

K
Krishna Kumar 已提交
1798
	sk_tx_queue_clear(sk);
1799
	sk->sk_dst_pending_confirm = 0;
1800 1801
	old_dst = rcu_dereference_protected(sk->sk_dst_cache,
					    lockdep_sock_is_held(sk));
E
Eric Dumazet 已提交
1802
	rcu_assign_pointer(sk->sk_dst_cache, dst);
L
Linus Torvalds 已提交
1803 1804 1805 1806 1807 1808
	dst_release(old_dst);
}

static inline void
sk_dst_set(struct sock *sk, struct dst_entry *dst)
{
1809 1810 1811
	struct dst_entry *old_dst;

	sk_tx_queue_clear(sk);
1812
	sk->sk_dst_pending_confirm = 0;
1813
	old_dst = xchg((__force struct dst_entry **)&sk->sk_dst_cache, dst);
1814
	dst_release(old_dst);
L
Linus Torvalds 已提交
1815 1816 1817 1818 1819
}

static inline void
__sk_dst_reset(struct sock *sk)
{
E
Eric Dumazet 已提交
1820
	__sk_dst_set(sk, NULL);
L
Linus Torvalds 已提交
1821 1822 1823 1824 1825
}

static inline void
sk_dst_reset(struct sock *sk)
{
1826
	sk_dst_set(sk, NULL);
L
Linus Torvalds 已提交
1827 1828
}

1829
struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
L
Linus Torvalds 已提交
1830

1831
struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
L
Linus Torvalds 已提交
1832

1833 1834 1835 1836 1837 1838
static inline void sk_dst_confirm(struct sock *sk)
{
	if (!sk->sk_dst_pending_confirm)
		sk->sk_dst_pending_confirm = 1;
}

1839 1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852
static inline void sock_confirm_neigh(struct sk_buff *skb, struct neighbour *n)
{
	if (skb_get_dst_pending_confirm(skb)) {
		struct sock *sk = skb->sk;
		unsigned long now = jiffies;

		/* avoid dirtying neighbour */
		if (n->confirmed != now)
			n->confirmed = now;
		if (sk && sk->sk_dst_pending_confirm)
			sk->sk_dst_pending_confirm = 0;
	}
}

1853 1854
bool sk_mc_loop(struct sock *sk);

E
Eric Dumazet 已提交
1855
static inline bool sk_can_gso(const struct sock *sk)
1856 1857 1858 1859
{
	return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type);
}

1860
void sk_setup_caps(struct sock *sk, struct dst_entry *dst);
1861

1862
static inline void sk_nocaps_add(struct sock *sk, netdev_features_t flags)
E
Eric Dumazet 已提交
1863 1864 1865 1866 1867
{
	sk->sk_route_nocaps |= flags;
	sk->sk_route_caps &= ~flags;
}

1868
static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
1869
					   struct iov_iter *from, char *to,
1870
					   int copy, int offset)
1871 1872
{
	if (skb->ip_summed == CHECKSUM_NONE) {
1873
		__wsum csum = 0;
1874
		if (!csum_and_copy_from_iter_full(to, copy, &csum, from))
1875
			return -EFAULT;
1876
		skb->csum = csum_block_add(skb->csum, csum, offset);
1877
	} else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
1878
		if (!copy_from_iter_full_nocache(to, copy, from))
1879
			return -EFAULT;
1880
	} else if (!copy_from_iter_full(to, copy, from))
1881 1882 1883 1884 1885 1886
		return -EFAULT;

	return 0;
}

static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
1887
				       struct iov_iter *from, int copy)
1888
{
1889
	int err, offset = skb->len;
1890

1891 1892
	err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy),
				       copy, offset);
1893
	if (err)
1894
		__skb_trim(skb, offset);
1895 1896 1897 1898

	return err;
}

1899
static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from,
1900 1901 1902 1903 1904 1905
					   struct sk_buff *skb,
					   struct page *page,
					   int off, int copy)
{
	int err;

1906 1907
	err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off,
				       copy, skb->len);
1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918
	if (err)
		return err;

	skb->len	     += copy;
	skb->data_len	     += copy;
	skb->truesize	     += copy;
	sk->sk_wmem_queued   += copy;
	sk_mem_charge(sk, copy);
	return 0;
}

1919 1920 1921 1922 1923 1924 1925 1926
/**
 * sk_wmem_alloc_get - returns write allocations
 * @sk: socket
 *
 * Returns sk_wmem_alloc minus initial offset of one
 */
static inline int sk_wmem_alloc_get(const struct sock *sk)
{
1927
	return refcount_read(&sk->sk_wmem_alloc) - 1;
1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 1945 1946
}

/**
 * sk_rmem_alloc_get - returns read allocations
 * @sk: socket
 *
 * Returns sk_rmem_alloc
 */
static inline int sk_rmem_alloc_get(const struct sock *sk)
{
	return atomic_read(&sk->sk_rmem_alloc);
}

/**
 * sk_has_allocations - check if allocations are outstanding
 * @sk: socket
 *
 * Returns true if socket has write or read allocations
 */
E
Eric Dumazet 已提交
1947
static inline bool sk_has_allocations(const struct sock *sk)
1948 1949 1950 1951
{
	return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk);
}

1952
/**
H
Herbert Xu 已提交
1953
 * skwq_has_sleeper - check if there are any waiting processes
R
Randy Dunlap 已提交
1954
 * @wq: struct socket_wq
1955
 *
1956
 * Returns true if socket_wq has waiting processes
1957
 *
H
Herbert Xu 已提交
1958
 * The purpose of the skwq_has_sleeper and sock_poll_wait is to wrap the memory
1959 1960
 * barrier call. They were added due to the race found within the tcp code.
 *
1961
 * Consider following tcp code paths::
1962
 *
1963 1964
 *   CPU1                CPU2
 *   sys_select          receive packet
1965 1966 1967 1968 1969
 *   ...                 ...
 *   __add_wait_queue    update tp->rcv_nxt
 *   ...                 ...
 *   tp->rcv_nxt check   sock_def_readable
 *   ...                 {
1970 1971 1972 1973
 *   schedule               rcu_read_lock();
 *                          wq = rcu_dereference(sk->sk_wq);
 *                          if (wq && waitqueue_active(&wq->wait))
 *                              wake_up_interruptible(&wq->wait)
1974 1975 1976 1977 1978 1979 1980
 *                          ...
 *                       }
 *
 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
 * in its cache, and so does the tp->rcv_nxt update on CPU2 side.  The CPU1
 * could then endup calling schedule and sleep forever if there are no more
 * data on the socket.
1981
 *
1982
 */
H
Herbert Xu 已提交
1983
static inline bool skwq_has_sleeper(struct socket_wq *wq)
1984
{
H
Herbert Xu 已提交
1985
	return wq && wq_has_sleeper(&wq->wait);
1986 1987 1988 1989 1990 1991 1992 1993
}

/**
 * sock_poll_wait - place memory barrier behind the poll_wait call.
 * @filp:           file
 * @wait_address:   socket wait queue
 * @p:              poll_table
 *
1994
 * See the comments in the wq_has_sleeper function.
1995 1996 1997 1998
 */
static inline void sock_poll_wait(struct file *filp,
		wait_queue_head_t *wait_address, poll_table *p)
{
1999
	if (!poll_does_not_wait(p) && wait_address) {
2000
		poll_wait(filp, wait_address, p);
E
Eric Dumazet 已提交
2001
		/* We need to be sure we are in sync with the
2002 2003
		 * socket flags modification.
		 *
2004
		 * This memory barrier is paired in the wq_has_sleeper.
E
Eric Dumazet 已提交
2005
		 */
2006 2007 2008 2009
		smp_mb();
	}
}

2010 2011 2012 2013 2014 2015 2016 2017
static inline void skb_set_hash_from_sk(struct sk_buff *skb, struct sock *sk)
{
	if (sk->sk_txhash) {
		skb->l4_hash = 1;
		skb->hash = sk->sk_txhash;
	}
}

2018 2019
void skb_set_owner_w(struct sk_buff *skb, struct sock *sk);

L
Linus Torvalds 已提交
2020
/*
E
Eric Dumazet 已提交
2021
 *	Queue a received datagram if it will fit. Stream and sequenced
L
Linus Torvalds 已提交
2022 2023 2024
 *	protocols can't normally use this as they need to fit buffers in
 *	and play with them.
 *
E
Eric Dumazet 已提交
2025
 *	Inlined as it's very short and called for pretty much every
L
Linus Torvalds 已提交
2026 2027 2028 2029
 *	packet ever received.
 */
static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
{
2030
	skb_orphan(skb);
L
Linus Torvalds 已提交
2031 2032 2033
	skb->sk = sk;
	skb->destructor = sock_rfree;
	atomic_add(skb->truesize, &sk->sk_rmem_alloc);
2034
	sk_mem_charge(sk, skb->truesize);
L
Linus Torvalds 已提交
2035 2036
}

2037 2038
void sk_reset_timer(struct sock *sk, struct timer_list *timer,
		    unsigned long expires);
L
Linus Torvalds 已提交
2039

2040
void sk_stop_timer(struct sock *sk, struct timer_list *timer);
L
Linus Torvalds 已提交
2041

2042 2043
int __sk_queue_drop_skb(struct sock *sk, struct sk_buff_head *sk_queue,
			struct sk_buff *skb, unsigned int flags,
2044 2045
			void (*destructor)(struct sock *sk,
					   struct sk_buff *skb));
2046
int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
2047
int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
L
Linus Torvalds 已提交
2048

2049
int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
2050
struct sk_buff *sock_dequeue_err_skb(struct sock *sk);
L
Linus Torvalds 已提交
2051 2052 2053 2054

/*
 *	Recover an error report and clear atomically
 */
E
Eric Dumazet 已提交
2055

L
Linus Torvalds 已提交
2056 2057
static inline int sock_error(struct sock *sk)
{
2058 2059 2060 2061
	int err;
	if (likely(!sk->sk_err))
		return 0;
	err = xchg(&sk->sk_err, 0);
L
Linus Torvalds 已提交
2062 2063 2064 2065 2066 2067 2068 2069
	return -err;
}

static inline unsigned long sock_wspace(struct sock *sk)
{
	int amt = 0;

	if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
2070
		amt = sk->sk_sndbuf - refcount_read(&sk->sk_wmem_alloc);
E
Eric Dumazet 已提交
2071
		if (amt < 0)
L
Linus Torvalds 已提交
2072 2073 2074 2075 2076
			amt = 0;
	}
	return amt;
}

2077 2078 2079 2080
/* Note:
 *  We use sk->sk_wq_raw, from contexts knowing this
 *  pointer is not NULL and cannot disappear/change.
 */
2081
static inline void sk_set_bit(int nr, struct sock *sk)
L
Linus Torvalds 已提交
2082
{
2083 2084
	if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
	    !sock_flag(sk, SOCK_FASYNC))
2085 2086
		return;

2087
	set_bit(nr, &sk->sk_wq_raw->flags);
2088 2089 2090 2091
}

static inline void sk_clear_bit(int nr, struct sock *sk)
{
2092 2093
	if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
	    !sock_flag(sk, SOCK_FASYNC))
2094 2095
		return;

2096
	clear_bit(nr, &sk->sk_wq_raw->flags);
2097 2098
}

2099
static inline void sk_wake_async(const struct sock *sk, int how, int band)
L
Linus Torvalds 已提交
2100
{
2101 2102 2103 2104 2105
	if (sock_flag(sk, SOCK_FASYNC)) {
		rcu_read_lock();
		sock_wake_async(rcu_dereference(sk->sk_wq), how, band);
		rcu_read_unlock();
	}
L
Linus Torvalds 已提交
2106 2107
}

2108 2109 2110 2111
/* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might
 * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak.
 * Note: for send buffers, TCP works better if we can build two skbs at
 * minimum.
E
Eric Dumazet 已提交
2112
 */
2113
#define TCP_SKB_MIN_TRUESIZE	(2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff)))
2114 2115 2116

#define SOCK_MIN_SNDBUF		(TCP_SKB_MIN_TRUESIZE * 2)
#define SOCK_MIN_RCVBUF		 TCP_SKB_MIN_TRUESIZE
L
Linus Torvalds 已提交
2117 2118 2119 2120

static inline void sk_stream_moderate_sndbuf(struct sock *sk)
{
	if (!(sk->sk_userlocks & SOCK_SNDBUF_LOCK)) {
2121
		sk->sk_sndbuf = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
2122
		sk->sk_sndbuf = max_t(u32, sk->sk_sndbuf, SOCK_MIN_SNDBUF);
L
Linus Torvalds 已提交
2123 2124 2125
	}
}

2126 2127
struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp,
				    bool force_schedule);
L
Linus Torvalds 已提交
2128

2129 2130 2131 2132 2133 2134 2135 2136
/**
 * sk_page_frag - return an appropriate page_frag
 * @sk: socket
 *
 * If socket allocation mode allows current thread to sleep, it means its
 * safe to use the per task page_frag instead of the per socket one.
 */
static inline struct page_frag *sk_page_frag(struct sock *sk)
L
Linus Torvalds 已提交
2137
{
2138
	if (gfpflags_allow_blocking(sk->sk_allocation))
2139
		return &current->task_frag;
L
Linus Torvalds 已提交
2140

2141
	return &sk->sk_frag;
L
Linus Torvalds 已提交
2142 2143
}

2144
bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag);
2145

2146
int sk_alloc_sg(struct sock *sk, int len, struct scatterlist *sg,
2147
		int sg_start, int *sg_curr, unsigned int *sg_size,
2148 2149
		int first_coalesce);

L
Linus Torvalds 已提交
2150 2151 2152
/*
 *	Default write policy as shown to user space via poll/select/SIGIO
 */
E
Eric Dumazet 已提交
2153
static inline bool sock_writeable(const struct sock *sk)
L
Linus Torvalds 已提交
2154
{
2155
	return refcount_read(&sk->sk_wmem_alloc) < (sk->sk_sndbuf >> 1);
L
Linus Torvalds 已提交
2156 2157
}

A
Al Viro 已提交
2158
static inline gfp_t gfp_any(void)
L
Linus Torvalds 已提交
2159
{
2160
	return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
L
Linus Torvalds 已提交
2161 2162
}

E
Eric Dumazet 已提交
2163
static inline long sock_rcvtimeo(const struct sock *sk, bool noblock)
L
Linus Torvalds 已提交
2164 2165 2166 2167
{
	return noblock ? 0 : sk->sk_rcvtimeo;
}

E
Eric Dumazet 已提交
2168
static inline long sock_sndtimeo(const struct sock *sk, bool noblock)
L
Linus Torvalds 已提交
2169 2170 2171 2172 2173 2174 2175 2176 2177 2178 2179 2180 2181 2182 2183 2184 2185
{
	return noblock ? 0 : sk->sk_sndtimeo;
}

static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
{
	return (waitall ? len : min_t(int, sk->sk_rcvlowat, len)) ? : 1;
}

/* Alas, with timeout socket operations are not restartable.
 * Compare this to poll().
 */
static inline int sock_intr_errno(long timeo)
{
	return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
}

2186 2187 2188 2189 2190 2191 2192 2193 2194 2195 2196 2197 2198 2199
struct sock_skb_cb {
	u32 dropcount;
};

/* Store sock_skb_cb at the end of skb->cb[] so protocol families
 * using skb->cb[] would keep using it directly and utilize its
 * alignement guarantee.
 */
#define SOCK_SKB_CB_OFFSET ((FIELD_SIZEOF(struct sk_buff, cb) - \
			    sizeof(struct sock_skb_cb)))

#define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \
			    SOCK_SKB_CB_OFFSET))

2200
#define sock_skb_cb_check_size(size) \
2201
	BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET)
2202

2203 2204 2205
static inline void
sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb)
{
2206 2207
	SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, SOCK_RXQ_OVFL) ?
						atomic_read(&sk->sk_drops) : 0;
2208 2209
}

2210 2211 2212 2213 2214 2215 2216
static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb)
{
	int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs);

	atomic_add(segs, &sk->sk_drops);
}

2217 2218 2219 2220
void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
			   struct sk_buff *skb);
void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
			     struct sk_buff *skb);
2221

E
Eric Dumazet 已提交
2222
static inline void
L
Linus Torvalds 已提交
2223 2224
sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
{
2225
	ktime_t kt = skb->tstamp;
2226
	struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
2227

2228 2229
	/*
	 * generate control messages if
2230
	 * - receive time stamping in software requested
2231 2232 2233 2234
	 * - software time stamp available and wanted
	 * - hardware time stamps available and wanted
	 */
	if (sock_flag(sk, SOCK_RCVTSTAMP) ||
2235
	    (sk->sk_tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) ||
T
Thomas Gleixner 已提交
2236 2237
	    (kt && sk->sk_tsflags & SOF_TIMESTAMPING_SOFTWARE) ||
	    (hwtstamps->hwtstamp &&
2238
	     (sk->sk_tsflags & SOF_TIMESTAMPING_RAW_HARDWARE)))
2239 2240
		__sock_recv_timestamp(msg, sk, skb);
	else
2241
		sk->sk_stamp = kt;
2242 2243 2244

	if (sock_flag(sk, SOCK_WIFI_STATUS) && skb->wifi_acked_valid)
		__sock_recv_wifi_status(msg, sk, skb);
L
Linus Torvalds 已提交
2245 2246
}

2247 2248
void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
			      struct sk_buff *skb);
2249

2250
#define SK_DEFAULT_STAMP (-1L * NSEC_PER_SEC)
2251 2252 2253 2254
static inline void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
					  struct sk_buff *skb)
{
#define FLAGS_TS_OR_DROPS ((1UL << SOCK_RXQ_OVFL)			| \
2255 2256 2257
			   (1UL << SOCK_RCVTSTAMP))
#define TSFLAGS_ANY	  (SOF_TIMESTAMPING_SOFTWARE			| \
			   SOF_TIMESTAMPING_RAW_HARDWARE)
2258

2259
	if (sk->sk_flags & FLAGS_TS_OR_DROPS || sk->sk_tsflags & TSFLAGS_ANY)
2260
		__sock_recv_ts_and_drops(msg, sk, skb);
2261
	else if (unlikely(sock_flag(sk, SOCK_TIMESTAMP)))
2262
		sk->sk_stamp = skb->tstamp;
2263 2264
	else if (unlikely(sk->sk_stamp == SK_DEFAULT_STAMP))
		sk->sk_stamp = 0;
2265
}
2266

2267
void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags);
2268

2269 2270 2271
/**
 * sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
 * @sk:		socket sending this packet
2272
 * @tsflags:	timestamping flags to use
2273 2274
 * @tx_flags:	completed with instructions for time stamping
 *
2275
 * Note: callers should take care of initial ``*tx_flags`` value (usually 0)
2276
 */
2277 2278
static inline void sock_tx_timestamp(const struct sock *sk, __u16 tsflags,
				     __u8 *tx_flags)
2279
{
2280 2281
	if (unlikely(tsflags))
		__sock_tx_timestamp(tsflags, tx_flags);
2282 2283 2284
	if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS)))
		*tx_flags |= SKBTX_WIFI_STATUS;
}
2285

L
Linus Torvalds 已提交
2286 2287
/**
 * sk_eat_skb - Release a skb if it is no longer needed
2288 2289
 * @sk: socket to eat this skb from
 * @skb: socket buffer to eat
L
Linus Torvalds 已提交
2290 2291 2292 2293
 *
 * This routine must be called with interrupts disabled or with the socket
 * locked so that the sk_buff queue operation is ok.
*/
D
Dan Williams 已提交
2294
static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb)
L
Linus Torvalds 已提交
2295 2296 2297 2298 2299
{
	__skb_unlink(skb, &sk->sk_receive_queue);
	__kfree_skb(skb);
}

2300 2301 2302
static inline
struct net *sock_net(const struct sock *sk)
{
E
Eric Dumazet 已提交
2303
	return read_pnet(&sk->sk_net);
2304 2305 2306
}

static inline
2307
void sock_net_set(struct sock *sk, struct net *net)
2308
{
E
Eric Dumazet 已提交
2309
	write_pnet(&sk->sk_net, net);
2310 2311
}

2312 2313
static inline struct sock *skb_steal_sock(struct sk_buff *skb)
{
2314
	if (skb->sk) {
2315 2316 2317 2318 2319 2320 2321 2322 2323
		struct sock *sk = skb->sk;

		skb->destructor = NULL;
		skb->sk = NULL;
		return sk;
	}
	return NULL;
}

E
Eric Dumazet 已提交
2324 2325 2326 2327 2328 2329 2330 2331
/* This helper checks if a socket is a full socket,
 * ie _not_ a timewait or request socket.
 */
static inline bool sk_fullsock(const struct sock *sk)
{
	return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV);
}

2332 2333 2334 2335 2336 2337 2338 2339
/* This helper checks if a socket is a LISTEN or NEW_SYN_RECV
 * SYNACK messages can be attached to either ones (depending on SYNCOOKIE)
 */
static inline bool sk_listener(const struct sock *sk)
{
	return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV);
}

2340 2341 2342 2343 2344
void sock_enable_timestamp(struct sock *sk, int flag);
int sock_get_timestamp(struct sock *, struct timeval __user *);
int sock_get_timestampns(struct sock *, struct timespec __user *);
int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level,
		       int type);
L
Linus Torvalds 已提交
2345

2346 2347 2348 2349 2350
bool sk_ns_capable(const struct sock *sk,
		   struct user_namespace *user_ns, int cap);
bool sk_capable(const struct sock *sk, int cap);
bool sk_net_capable(const struct sock *sk, int cap);

2351 2352
void sk_get_meminfo(const struct sock *sk, u32 *meminfo);

2353 2354 2355 2356 2357 2358 2359 2360 2361 2362
/* Take into consideration the size of the struct sk_buff overhead in the
 * determination of these values, since that is non-constant across
 * platforms.  This makes socket queueing behavior and performance
 * not depend upon such differences.
 */
#define _SK_MEM_PACKETS		256
#define _SK_MEM_OVERHEAD	SKB_TRUESIZE(256)
#define SK_WMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
#define SK_RMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)

L
Linus Torvalds 已提交
2363 2364 2365
extern __u32 sysctl_wmem_max;
extern __u32 sysctl_rmem_max;

2366
extern int sysctl_tstamp_allow_data;
2367 2368
extern int sysctl_optmem_max;

2369 2370 2371
extern __u32 sysctl_wmem_default;
extern __u32 sysctl_rmem_default;

2372 2373 2374 2375 2376 2377 2378 2379 2380 2381 2382 2383 2384 2385 2386 2387 2388 2389
static inline int sk_get_wmem0(const struct sock *sk, const struct proto *proto)
{
	/* Does this proto have per netns sysctl_wmem ? */
	if (proto->sysctl_wmem_offset)
		return *(int *)((void *)sock_net(sk) + proto->sysctl_wmem_offset);

	return *proto->sysctl_wmem;
}

static inline int sk_get_rmem0(const struct sock *sk, const struct proto *proto)
{
	/* Does this proto have per netns sysctl_rmem ? */
	if (proto->sysctl_rmem_offset)
		return *(int *)((void *)sock_net(sk) + proto->sysctl_rmem_offset);

	return *proto->sysctl_rmem;
}

2390 2391 2392 2393 2394 2395 2396 2397 2398 2399 2400
/* Default TCP Small queue budget is ~1 ms of data (1sec >> 10)
 * Some wifi drivers need to tweak it to get more chunks.
 * They can use this helper from their ndo_start_xmit()
 */
static inline void sk_pacing_shift_update(struct sock *sk, int val)
{
	if (!sk || !sk_fullsock(sk) || sk->sk_pacing_shift == val)
		return;
	sk->sk_pacing_shift = val;
}

2401 2402 2403 2404 2405 2406 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416 2417 2418 2419
/* if a socket is bound to a device, check that the given device
 * index is either the same or that the socket is bound to an L3
 * master device and the given device index is also enslaved to
 * that L3 master
 */
static inline bool sk_dev_equal_l3scope(struct sock *sk, int dif)
{
	int mdif;

	if (!sk->sk_bound_dev_if || sk->sk_bound_dev_if == dif)
		return true;

	mdif = l3mdev_master_ifindex_by_index(sock_net(sk), dif);
	if (mdif && mdif == sk->sk_bound_dev_if)
		return true;

	return false;
}

L
Linus Torvalds 已提交
2420
#endif	/* _SOCK_H */