sock.h 68.8 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;
	};
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	unsigned short		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);
484 485 486 487 488
#ifdef CONFIG_SOCK_VALIDATE_XMIT
	struct sk_buff*		(*sk_validate_xmit_skb)(struct sock *sk,
							struct net_device *dev,
							struct sk_buff *skb);
#endif
L
Linus Torvalds 已提交
489
	void                    (*sk_destruct)(struct sock *sk);
490
	struct sock_reuseport __rcu	*sk_reuseport_cb;
491
	struct rcu_head		sk_rcu;
L
Linus Torvalds 已提交
492 493
};

494 495 496 497 498 499
enum sk_pacing {
	SK_PACING_NONE		= 0,
	SK_PACING_NEEDED	= 1,
	SK_PACING_FQ		= 2,
};

500 501 502 503 504
#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)

505 506 507 508 509 510 511 512 513 514 515
/*
 * 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

516 517
int sk_set_peek_off(struct sock *sk, int val);

518 519
static inline int sk_peek_offset(struct sock *sk, int flags)
{
520
	if (unlikely(flags & MSG_PEEK)) {
521
		return READ_ONCE(sk->sk_peek_off);
522 523 524
	}

	return 0;
525 526 527 528
}

static inline void sk_peek_offset_bwd(struct sock *sk, int val)
{
529 530 531 532 533
	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);
534 535 536 537 538
	}
}

static inline void sk_peek_offset_fwd(struct sock *sk, int val)
{
539
	sk_peek_offset_bwd(sk, -val);
540 541
}

L
Linus Torvalds 已提交
542 543 544
/*
 * Hashed lists helper routines
 */
L
Li Zefan 已提交
545 546 547 548 549
static inline struct sock *sk_entry(const struct hlist_node *node)
{
	return hlist_entry(node, 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_entry(head->first, struct sock, sk_node);
}

555
static inline struct sock *sk_head(const struct hlist_head *head)
L
Linus Torvalds 已提交
556 557 558 559
{
	return hlist_empty(head) ? NULL : __sk_head(head);
}

560 561 562 563 564 565 566 567 568 569
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);
}

570
static inline struct sock *sk_next(const struct sock *sk)
L
Linus Torvalds 已提交
571
{
G
Geliang Tang 已提交
572
	return hlist_entry_safe(sk->sk_node.next, struct sock, sk_node);
L
Linus Torvalds 已提交
573 574
}

575 576 577 578 579 580 581 582
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
583
static inline bool sk_unhashed(const struct sock *sk)
L
Linus Torvalds 已提交
584 585 586 587
{
	return hlist_unhashed(&sk->sk_node);
}

E
Eric Dumazet 已提交
588
static inline bool sk_hashed(const struct sock *sk)
L
Linus Torvalds 已提交
589
{
A
Akinobu Mita 已提交
590
	return !sk_unhashed(sk);
L
Linus Torvalds 已提交
591 592
}

E
Eric Dumazet 已提交
593
static inline void sk_node_init(struct hlist_node *node)
L
Linus Torvalds 已提交
594 595 596 597
{
	node->pprev = NULL;
}

E
Eric Dumazet 已提交
598
static inline void sk_nulls_node_init(struct hlist_nulls_node *node)
599 600 601 602
{
	node->pprev = NULL;
}

E
Eric Dumazet 已提交
603
static inline void __sk_del_node(struct sock *sk)
L
Linus Torvalds 已提交
604 605 606 607
{
	__hlist_del(&sk->sk_node);
}

608
/* NB: equivalent to hlist_del_init_rcu */
E
Eric Dumazet 已提交
609
static inline bool __sk_del_node_init(struct sock *sk)
L
Linus Torvalds 已提交
610 611 612 613
{
	if (sk_hashed(sk)) {
		__sk_del_node(sk);
		sk_node_init(&sk->sk_node);
E
Eric Dumazet 已提交
614
		return true;
L
Linus Torvalds 已提交
615
	}
E
Eric Dumazet 已提交
616
	return false;
L
Linus Torvalds 已提交
617 618 619 620 621 622 623 624
}

/* 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.
 */

625
static __always_inline void sock_hold(struct sock *sk)
L
Linus Torvalds 已提交
626
{
627
	refcount_inc(&sk->sk_refcnt);
L
Linus Torvalds 已提交
628 629 630 631 632
}

/* Ungrab socket in the context, which assumes that socket refcnt
   cannot hit zero, f.e. it is true in context of any socketcall.
 */
633
static __always_inline void __sock_put(struct sock *sk)
L
Linus Torvalds 已提交
634
{
635
	refcount_dec(&sk->sk_refcnt);
L
Linus Torvalds 已提交
636 637
}

E
Eric Dumazet 已提交
638
static inline bool sk_del_node_init(struct sock *sk)
L
Linus Torvalds 已提交
639
{
E
Eric Dumazet 已提交
640
	bool rc = __sk_del_node_init(sk);
L
Linus Torvalds 已提交
641 642 643

	if (rc) {
		/* paranoid for a while -acme */
644
		WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
L
Linus Torvalds 已提交
645 646 647 648
		__sock_put(sk);
	}
	return rc;
}
649
#define sk_del_node_init_rcu(sk)	sk_del_node_init(sk)
L
Linus Torvalds 已提交
650

E
Eric Dumazet 已提交
651
static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk)
652 653
{
	if (sk_hashed(sk)) {
654
		hlist_nulls_del_init_rcu(&sk->sk_nulls_node);
E
Eric Dumazet 已提交
655
		return true;
656
	}
E
Eric Dumazet 已提交
657
	return false;
658 659
}

E
Eric Dumazet 已提交
660
static inline bool sk_nulls_del_node_init_rcu(struct sock *sk)
661
{
E
Eric Dumazet 已提交
662
	bool rc = __sk_nulls_del_node_init_rcu(sk);
663 664 665

	if (rc) {
		/* paranoid for a while -acme */
666
		WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
667 668 669 670 671
		__sock_put(sk);
	}
	return rc;
}

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
{
	hlist_add_head(&sk->sk_node, list);
}

E
Eric Dumazet 已提交
677
static inline void sk_add_node(struct sock *sk, struct hlist_head *list)
L
Linus Torvalds 已提交
678 679 680 681 682
{
	sock_hold(sk);
	__sk_add_node(sk, list);
}

E
Eric Dumazet 已提交
683
static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list)
684 685
{
	sock_hold(sk);
686 687 688 689 690
	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);
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
	hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list);
696 697
}

E
Eric Dumazet 已提交
698
static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
699 700
{
	sock_hold(sk);
701
	__sk_nulls_add_node_rcu(sk, list);
702 703
}

E
Eric Dumazet 已提交
704
static inline void __sk_del_bind_node(struct sock *sk)
L
Linus Torvalds 已提交
705 706 707 708
{
	__hlist_del(&sk->sk_bind_node);
}

E
Eric Dumazet 已提交
709
static inline void sk_add_bind_node(struct sock *sk,
L
Linus Torvalds 已提交
710 711 712 713 714
					struct hlist_head *list)
{
	hlist_add_head(&sk->sk_bind_node, list);
}

715 716 717 718
#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)
719 720 721 722
#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)
723 724
#define sk_for_each_from(__sk) \
	hlist_for_each_entry_from(__sk, sk_node)
725 726 727
#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)
728 729 730 731
#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
732

733
/**
734
 * sk_for_each_entry_offset_rcu - iterate over a list at a given struct offset
735 736 737 738 739 740
 * @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.
 *
 */
741
#define sk_for_each_entry_offset_rcu(tpos, pos, head, offset)		       \
742
	for (pos = rcu_dereference(hlist_first_rcu(head));		       \
743
	     pos != NULL &&						       \
744
		({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;});       \
745
	     pos = rcu_dereference(hlist_next_rcu(pos)))
746

E
Eric W. Biederman 已提交
747 748 749 750 751 752 753 754 755
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
756 757 758 759 760 761 762 763 764 765 766 767 768 769
/* 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 */
770
	SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */
L
Linus Torvalds 已提交
771 772
	SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
	SOCK_QUEUE_SHRUNK, /* write queue has been shrunk recently */
773
	SOCK_MEMALLOC, /* VM depends on this socket for swapping */
774
	SOCK_TIMESTAMPING_RX_SOFTWARE,  /* %SOF_TIMESTAMPING_RX_SOFTWARE */
E
Eric Dumazet 已提交
775
	SOCK_FASYNC, /* fasync() active */
776
	SOCK_RXQ_OVFL,
777
	SOCK_ZEROCOPY, /* buffers from userspace */
778
	SOCK_WIFI_STATUS, /* push wifi status to userspace */
779 780 781 782
	SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS.
		     * Will use last 4 bytes of packet sent from
		     * user-space instead.
		     */
783
	SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */
784
	SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */
785
	SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */
L
Linus Torvalds 已提交
786 787
};

788 789
#define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))

R
Ralf Baechle 已提交
790 791 792 793 794
static inline void sock_copy_flags(struct sock *nsk, struct sock *osk)
{
	nsk->sk_flags = osk->sk_flags;
}

L
Linus Torvalds 已提交
795 796 797 798 799 800 801 802 803 804
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
805
static inline bool sock_flag(const struct sock *sk, enum sock_flags flag)
L
Linus Torvalds 已提交
806 807 808 809
{
	return test_bit(flag, &sk->sk_flags);
}

810
#ifdef CONFIG_NET
811
DECLARE_STATIC_KEY_FALSE(memalloc_socks_key);
812 813
static inline int sk_memalloc_socks(void)
{
814
	return static_branch_unlikely(&memalloc_socks_key);
815 816 817 818 819 820 821 822 823 824
}
#else

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

#endif

825
static inline gfp_t sk_gfp_mask(const struct sock *sk, gfp_t gfp_mask)
826
{
827
	return gfp_mask | (sk->sk_allocation & __GFP_MEMALLOC);
828 829
}

L
Linus Torvalds 已提交
830 831 832 833 834 835 836 837 838 839
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
840
static inline bool sk_acceptq_is_full(const struct sock *sk)
L
Linus Torvalds 已提交
841
{
842
	return sk->sk_ack_backlog > sk->sk_max_ack_backlog;
L
Linus Torvalds 已提交
843 844 845 846 847
}

/*
 * Compute minimal free write space needed to queue new packets.
 */
E
Eric Dumazet 已提交
848
static inline int sk_stream_min_wspace(const struct sock *sk)
L
Linus Torvalds 已提交
849
{
850
	return sk->sk_wmem_queued >> 1;
L
Linus Torvalds 已提交
851 852
}

E
Eric Dumazet 已提交
853
static inline int sk_stream_wspace(const struct sock *sk)
L
Linus Torvalds 已提交
854 855 856 857
{
	return sk->sk_sndbuf - sk->sk_wmem_queued;
}

858
void sk_stream_write_space(struct sock *sk);
L
Linus Torvalds 已提交
859

Z
Zhu Yi 已提交
860
/* OOB backlog add */
Z
Zhu Yi 已提交
861
static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
862
{
E
Eric Dumazet 已提交
863
	/* dont let skb dst not refcounted, we are going to leave rcu lock */
E
Eric Dumazet 已提交
864
	skb_dst_force(skb);
E
Eric Dumazet 已提交
865 866 867 868

	if (!sk->sk_backlog.tail)
		sk->sk_backlog.head = skb;
	else
869
		sk->sk_backlog.tail->next = skb;
E
Eric Dumazet 已提交
870 871

	sk->sk_backlog.tail = skb;
872 873
	skb->next = NULL;
}
L
Linus Torvalds 已提交
874

875 876
/*
 * Take into account size of receive queue and backlog queue
E
Eric Dumazet 已提交
877 878
 * Do not take into account this skb truesize,
 * to allow even a single big packet to come.
879
 */
880
static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit)
881 882 883
{
	unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc);

884
	return qsize > limit;
885 886
}

Z
Zhu Yi 已提交
887
/* The per-socket spinlock must be held here. */
888 889
static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb,
					      unsigned int limit)
Z
Zhu Yi 已提交
890
{
891
	if (sk_rcvqueues_full(sk, limit))
Z
Zhu Yi 已提交
892 893
		return -ENOBUFS;

894 895 896 897 898 899 900 901
	/*
	 * 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
902
	__sk_add_backlog(sk, skb);
Z
Zhu Yi 已提交
903 904 905 906
	sk->sk_backlog.len += skb->truesize;
	return 0;
}

907
int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb);
908

P
Peter Zijlstra 已提交
909 910
static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
{
911 912 913
	if (sk_memalloc_socks() && skb_pfmemalloc(skb))
		return __sk_backlog_rcv(sk, skb);

P
Peter Zijlstra 已提交
914 915 916
	return sk->sk_backlog_rcv(sk, skb);
}

E
Eric Dumazet 已提交
917 918
static inline void sk_incoming_cpu_update(struct sock *sk)
{
919 920 921 922
	int cpu = raw_smp_processor_id();

	if (unlikely(sk->sk_incoming_cpu != cpu))
		sk->sk_incoming_cpu = cpu;
E
Eric Dumazet 已提交
923 924
}

925
static inline void sock_rps_record_flow_hash(__u32 hash)
926 927 928 929 930 931
{
#ifdef CONFIG_RPS
	struct rps_sock_flow_table *sock_flow_table;

	rcu_read_lock();
	sock_flow_table = rcu_dereference(rps_sock_flow_table);
932
	rps_record_sock_flow(sock_flow_table, hash);
933 934 935 936
	rcu_read_unlock();
#endif
}

937 938
static inline void sock_rps_record_flow(const struct sock *sk)
{
939
#ifdef CONFIG_RPS
E
Eric Dumazet 已提交
940 941 942 943 944 945 946 947 948 949 950 951 952 953
	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);
	}
954
#endif
955 956
}

957 958
static inline void sock_rps_save_rxhash(struct sock *sk,
					const struct sk_buff *skb)
959 960
{
#ifdef CONFIG_RPS
961
	if (unlikely(sk->sk_rxhash != skb->hash))
962
		sk->sk_rxhash = skb->hash;
963 964 965
#endif
}

966 967 968 969 970 971 972
static inline void sock_rps_reset_rxhash(struct sock *sk)
{
#ifdef CONFIG_RPS
	sk->sk_rxhash = 0;
#endif
}

W
WANG Cong 已提交
973
#define sk_wait_event(__sk, __timeo, __condition, __wait)		\
S
Stephen Hemminger 已提交
974 975 976 977
	({	int __rc;						\
		release_sock(__sk);					\
		__rc = __condition;					\
		if (!__rc) {						\
W
WANG Cong 已提交
978 979 980
			*(__timeo) = wait_woken(__wait,			\
						TASK_INTERRUPTIBLE,	\
						*(__timeo));		\
S
Stephen Hemminger 已提交
981
		}							\
W
WANG Cong 已提交
982
		sched_annotate_sleep();					\
S
Stephen Hemminger 已提交
983 984 985 986
		lock_sock(__sk);					\
		__rc = __condition;					\
		__rc;							\
	})
L
Linus Torvalds 已提交
987

988 989 990 991 992 993 994
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
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995

996 997 998 999 1000 1001 1002 1003 1004 1005 1006
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;
}

1007
int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb);
L
Linus Torvalds 已提交
1008

1009
struct request_sock_ops;
1010
struct timewait_sock_ops;
1011
struct inet_hashinfo;
1012
struct raw_hashinfo;
1013
struct smc_hashinfo;
1014
struct module;
1015

E
Eric Dumazet 已提交
1016
/*
1017
 * caches using SLAB_TYPESAFE_BY_RCU should let .next pointer from nulls nodes
E
Eric Dumazet 已提交
1018 1019 1020 1021 1022 1023 1024 1025 1026 1027
 * 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
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1028 1029 1030 1031
/* Networking protocol blocks we attach to sockets.
 * socket layer -> transport layer interface
 */
struct proto {
E
Eric Dumazet 已提交
1032
	void			(*close)(struct sock *sk,
L
Linus Torvalds 已提交
1033
					long timeout);
A
Andrey Ignatov 已提交
1034 1035 1036
	int			(*pre_connect)(struct sock *sk,
					struct sockaddr *uaddr,
					int addr_len);
L
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1037
	int			(*connect)(struct sock *sk,
E
Eric Dumazet 已提交
1038
					struct sockaddr *uaddr,
L
Linus Torvalds 已提交
1039 1040 1041
					int addr_len);
	int			(*disconnect)(struct sock *sk, int flags);

1042 1043
	struct sock *		(*accept)(struct sock *sk, int flags, int *err,
					  bool kern);
L
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1044 1045 1046 1047

	int			(*ioctl)(struct sock *sk, int cmd,
					 unsigned long arg);
	int			(*init)(struct sock *sk);
1048
	void			(*destroy)(struct sock *sk);
L
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1049
	void			(*shutdown)(struct sock *sk, int how);
E
Eric Dumazet 已提交
1050
	int			(*setsockopt)(struct sock *sk, int level,
L
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1051
					int optname, char __user *optval,
1052
					unsigned int optlen);
E
Eric Dumazet 已提交
1053 1054 1055
	int			(*getsockopt)(struct sock *sk, int level,
					int optname, char __user *optval,
					int __user *option);
1056
	void			(*keepalive)(struct sock *sk, int valbool);
A
Alexey Dobriyan 已提交
1057
#ifdef CONFIG_COMPAT
1058 1059 1060
	int			(*compat_setsockopt)(struct sock *sk,
					int level,
					int optname, char __user *optval,
1061
					unsigned int optlen);
1062 1063 1064 1065
	int			(*compat_getsockopt)(struct sock *sk,
					int level,
					int optname, char __user *optval,
					int __user *option);
1066 1067
	int			(*compat_ioctl)(struct sock *sk,
					unsigned int cmd, unsigned long arg);
A
Alexey Dobriyan 已提交
1068
#endif
1069 1070 1071
	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
1072 1073
					   size_t len, int noblock, int flags,
					   int *addr_len);
L
Linus Torvalds 已提交
1074 1075
	int			(*sendpage)(struct sock *sk, struct page *page,
					int offset, size_t size, int flags);
E
Eric Dumazet 已提交
1076
	int			(*bind)(struct sock *sk,
L
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1077 1078
					struct sockaddr *uaddr, int addr_len);

E
Eric Dumazet 已提交
1079
	int			(*backlog_rcv) (struct sock *sk,
L
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1080 1081
						struct sk_buff *skb);

E
Eric Dumazet 已提交
1082 1083
	void		(*release_cb)(struct sock *sk);

L
Linus Torvalds 已提交
1084
	/* Keeping track of sk's, looking them up, and port selection methods. */
1085
	int			(*hash)(struct sock *sk);
L
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1086
	void			(*unhash)(struct sock *sk);
E
Eric Dumazet 已提交
1087
	void			(*rehash)(struct sock *sk);
L
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1088 1089
	int			(*get_port)(struct sock *sk, unsigned short snum);

1090
	/* Keeping track of sockets in use */
1091
#ifdef CONFIG_PROC_FS
1092
	unsigned int		inuse_idx;
1093
#endif
1094

1095
	bool			(*stream_memory_free)(const struct sock *sk);
1096
	bool			(*stream_memory_read)(const struct sock *sk);
L
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1097
	/* Memory pressure */
1098
	void			(*enter_memory_pressure)(struct sock *sk);
1099
	void			(*leave_memory_pressure)(struct sock *sk);
E
Eric Dumazet 已提交
1100
	atomic_long_t		*memory_allocated;	/* Current allocated memory. */
1101
	struct percpu_counter	*sockets_allocated;	/* Current number of sockets. */
L
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1102 1103 1104
	/*
	 * Pressure flag: try to collapse.
	 * Technical note: it is used by multiple contexts non atomically.
1105
	 * All the __sk_mem_schedule() is of this nature: accounting
L
Linus Torvalds 已提交
1106 1107
	 * is strict, actions are advisory and have some latency.
	 */
1108
	unsigned long		*memory_pressure;
E
Eric Dumazet 已提交
1109
	long			*sysctl_mem;
1110

L
Linus Torvalds 已提交
1111 1112
	int			*sysctl_wmem;
	int			*sysctl_rmem;
1113 1114 1115
	u32			sysctl_wmem_offset;
	u32			sysctl_rmem_offset;

L
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1116
	int			max_header;
1117
	bool			no_autobind;
L
Linus Torvalds 已提交
1118

1119
	struct kmem_cache	*slab;
L
Linus Torvalds 已提交
1120
	unsigned int		obj_size;
1121
	slab_flags_t		slab_flags;
1122 1123
	unsigned int		useroffset;	/* Usercopy region offset */
	unsigned int		usersize;	/* Usercopy region size */
L
Linus Torvalds 已提交
1124

1125
	struct percpu_counter	*orphan_count;
1126

1127
	struct request_sock_ops	*rsk_prot;
1128
	struct timewait_sock_ops *twsk_prot;
1129

1130 1131
	union {
		struct inet_hashinfo	*hashinfo;
1132
		struct udp_table	*udp_table;
1133
		struct raw_hashinfo	*raw_hash;
1134
		struct smc_hashinfo	*smc_hash;
1135
	} h;
1136

L
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1137 1138 1139 1140 1141
	struct module		*owner;

	char			name[32];

	struct list_head	node;
1142 1143
#ifdef SOCK_REFCNT_DEBUG
	atomic_t		socks;
G
Glauber Costa 已提交
1144
#endif
1145
	int			(*diag_destroy)(struct sock *sk, int err);
1146
} __randomize_layout;
G
Glauber Costa 已提交
1147

1148 1149
int proto_register(struct proto *prot, int alloc_slab);
void proto_unregister(struct proto *prot);
1150
int sock_load_diag_module(int family, int protocol);
L
Linus Torvalds 已提交
1151

1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164
#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));
}

1165
static inline void sk_refcnt_debug_release(const struct sock *sk)
1166
{
1167
	if (refcount_read(&sk->sk_refcnt) != 1)
1168
		printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n",
1169
		       sk->sk_prot->name, sk, refcount_read(&sk->sk_refcnt));
1170 1171 1172 1173 1174 1175 1176
}
#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 */

1177 1178 1179 1180 1181 1182 1183 1184 1185
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;
}

1186 1187
static inline bool sk_stream_is_writeable(const struct sock *sk)
{
1188 1189
	return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) &&
	       sk_stream_memory_free(sk);
1190
}
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1192 1193 1194 1195 1196 1197 1198 1199 1200 1201
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
}
1202

1203 1204 1205 1206 1207 1208 1209 1210 1211
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
1212

1213 1214
	if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
	    mem_cgroup_under_socket_pressure(sk->sk_memcg))
1215
		return true;
G
Glauber Costa 已提交
1216

1217
	return !!*sk->sk_prot->memory_pressure;
1218 1219 1220 1221 1222
}

static inline long
sk_memory_allocated(const struct sock *sk)
{
1223
	return atomic_long_read(sk->sk_prot->memory_allocated);
1224 1225 1226
}

static inline long
1227
sk_memory_allocated_add(struct sock *sk, int amt)
1228
{
1229
	return atomic_long_add_return(amt, sk->sk_prot->memory_allocated);
1230 1231 1232
}

static inline void
1233
sk_memory_allocated_sub(struct sock *sk, int amt)
1234
{
1235
	atomic_long_sub(amt, sk->sk_prot->memory_allocated);
1236 1237 1238 1239
}

static inline void sk_sockets_allocated_dec(struct sock *sk)
{
1240
	percpu_counter_dec(sk->sk_prot->sockets_allocated);
1241 1242 1243 1244
}

static inline void sk_sockets_allocated_inc(struct sock *sk)
{
1245
	percpu_counter_inc(sk->sk_prot->sockets_allocated);
1246 1247 1248 1249 1250
}

static inline int
sk_sockets_allocated_read_positive(struct sock *sk)
{
1251
	return percpu_counter_read_positive(sk->sk_prot->sockets_allocated);
1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273
}

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;
}

1274 1275

#ifdef CONFIG_PROC_FS
L
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1276
/* Called with local bh disabled */
1277 1278
void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc);
int sock_prot_inuse_get(struct net *net, struct proto *proto);
1279
int sock_inuse_get(struct net *net);
1280
#else
E
Eric Dumazet 已提交
1281
static inline void sock_prot_inuse_add(struct net *net, struct proto *prot,
1282
		int inc)
1283 1284 1285 1286
{
}
#endif

L
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1287

1288 1289 1290
/* With per-bucket locks this operation is not-atomic, so that
 * this version is not worse.
 */
1291
static inline int __sk_prot_rehash(struct sock *sk)
1292 1293
{
	sk->sk_prot->unhash(sk);
1294
	return sk->sk_prot->hash(sk);
1295 1296
}

L
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1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326
/* 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;
}

1327 1328 1329
/*
 * Functions for memory accounting
 */
1330
int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind);
1331
int __sk_mem_schedule(struct sock *sk, int size, int kind);
1332
void __sk_mem_reduce_allocated(struct sock *sk, int amount);
E
Eric Dumazet 已提交
1333
void __sk_mem_reclaim(struct sock *sk, int amount);
L
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1334

E
Eric Dumazet 已提交
1335 1336 1337 1338
/* 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
1339 1340 1341
#define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM)
#define SK_MEM_SEND	0
#define SK_MEM_RECV	1
L
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1342

E
Eric Dumazet 已提交
1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355
/* 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;
}

1356
static inline int sk_mem_pages(int amt)
L
Linus Torvalds 已提交
1357
{
1358
	return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT;
L
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1359 1360
}

E
Eric Dumazet 已提交
1361
static inline bool sk_has_account(struct sock *sk)
L
Linus Torvalds 已提交
1362
{
1363 1364
	/* return true if protocol supports memory accounting */
	return !!sk->sk_prot->memory_allocated;
L
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1365 1366
}

E
Eric Dumazet 已提交
1367
static inline bool sk_wmem_schedule(struct sock *sk, int size)
L
Linus Torvalds 已提交
1368
{
1369
	if (!sk_has_account(sk))
E
Eric Dumazet 已提交
1370
		return true;
1371 1372
	return size <= sk->sk_forward_alloc ||
		__sk_mem_schedule(sk, size, SK_MEM_SEND);
L
Linus Torvalds 已提交
1373 1374
}

1375
static inline bool
1376
sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size)
H
Herbert Xu 已提交
1377
{
1378
	if (!sk_has_account(sk))
E
Eric Dumazet 已提交
1379
		return true;
1380 1381 1382
	return size<= sk->sk_forward_alloc ||
		__sk_mem_schedule(sk, size, SK_MEM_RECV) ||
		skb_pfmemalloc(skb);
1383 1384 1385 1386 1387 1388 1389
}

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
1390
		__sk_mem_reclaim(sk, sk->sk_forward_alloc);
1391 1392
}

1393 1394 1395 1396 1397
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
1398
		__sk_mem_reclaim(sk, sk->sk_forward_alloc - 1);
1399 1400
}

1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412
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;
1413 1414 1415 1416 1417 1418 1419 1420 1421 1422

	/* 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);
1423 1424 1425 1426 1427 1428 1429 1430
}

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
1431 1432
}

1433 1434
static inline void sock_release_ownership(struct sock *sk)
{
1435 1436 1437 1438 1439 1440
	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_);
	}
1441 1442
}

1443 1444 1445 1446 1447 1448 1449
/*
 * 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
1450
#define sock_lock_init_class_and_name(sk, sname, skey, name, key)	\
1451
do {									\
1452
	sk->sk_lock.owned = 0;						\
1453 1454 1455 1456 1457
	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
1458
				(skey), (sname));				\
1459 1460 1461
	lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0);	\
} while (0)

1462
#ifdef CONFIG_LOCKDEP
1463
static inline bool lockdep_sock_is_held(const struct sock *sk)
1464 1465 1466 1467
{
	return lockdep_is_held(&sk->sk_lock) ||
	       lockdep_is_held(&sk->sk_lock.slock);
}
1468
#endif
1469

1470
void lock_sock_nested(struct sock *sk, int subclass);
1471 1472 1473 1474 1475 1476

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

1477
void release_sock(struct sock *sk);
L
Linus Torvalds 已提交
1478 1479 1480

/* BH context may only use the following locking interface. */
#define bh_lock_sock(__sk)	spin_lock(&((__sk)->sk_lock.slock))
1481 1482 1483
#define bh_lock_sock_nested(__sk) \
				spin_lock_nested(&((__sk)->sk_lock.slock), \
				SINGLE_DEPTH_NESTING)
L
Linus Torvalds 已提交
1484 1485
#define bh_unlock_sock(__sk)	spin_unlock(&((__sk)->sk_lock.slock))

1486
bool lock_sock_fast(struct sock *sk);
1487 1488 1489 1490 1491 1492 1493 1494 1495
/**
 * 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
1496
{
1497 1498 1499 1500
	if (slow)
		release_sock(sk);
	else
		spin_unlock_bh(&sk->sk_lock.slock);
E
Eric Dumazet 已提交
1501 1502
}

1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515 1516
/* 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.
 */

1517
static inline void sock_owned_by_me(const struct sock *sk)
1518 1519
{
#ifdef CONFIG_LOCKDEP
1520
	WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks);
1521
#endif
1522 1523 1524 1525 1526
}

static inline bool sock_owned_by_user(const struct sock *sk)
{
	sock_owned_by_me(sk);
1527 1528 1529
	return sk->sk_lock.owned;
}

T
Tom Herbert 已提交
1530 1531 1532 1533 1534
static inline bool sock_owned_by_user_nocheck(const struct sock *sk)
{
	return sk->sk_lock.owned;
}

1535 1536 1537 1538 1539 1540 1541
/* 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
1542

1543
struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1544
		      struct proto *prot, int kern);
1545
void sk_free(struct sock *sk);
1546
void sk_destruct(struct sock *sk);
1547
struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority);
1548
void sk_free_unlock_clone(struct sock *sk);
1549 1550 1551

struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
			     gfp_t priority);
E
Eric Dumazet 已提交
1552
void __sock_wfree(struct sk_buff *skb);
1553
void sock_wfree(struct sk_buff *skb);
1554 1555
struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
			     gfp_t priority);
1556 1557
void skb_orphan_partial(struct sk_buff *skb);
void sock_rfree(struct sk_buff *skb);
1558
void sock_efree(struct sk_buff *skb);
1559
#ifdef CONFIG_INET
1560
void sock_edemux(struct sk_buff *skb);
1561
#else
1562
#define sock_edemux sock_efree
1563
#endif
1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576

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);
1577
void sock_kzfree_s(struct sock *sk, void *mem, int size);
1578
void sk_send_sigurg(struct sock *sk);
L
Linus Torvalds 已提交
1579

E
Edward Jee 已提交
1580 1581
struct sockcm_cookie {
	u32 mark;
1582
	u16 tsflags;
E
Edward Jee 已提交
1583 1584
};

1585 1586
int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg,
		     struct sockcm_cookie *sockc);
E
Edward Jee 已提交
1587 1588 1589
int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
		   struct sockcm_cookie *sockc);

L
Linus Torvalds 已提交
1590 1591 1592 1593
/*
 * Functions to fill in entries in struct proto_ops when a protocol
 * does not implement a particular function.
 */
1594 1595 1596
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 *);
1597
int sock_no_accept(struct socket *, struct socket *, int, bool);
1598
int sock_no_getname(struct socket *, struct sockaddr *, int);
1599 1600 1601 1602 1603
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);
1604
int sock_no_sendmsg(struct socket *, struct msghdr *, size_t);
1605
int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len);
1606
int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int);
1607 1608 1609 1610
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);
1611 1612
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
1613 1614 1615 1616 1617

/*
 * Functions to fill in entries in struct proto_ops when a protocol
 * uses the inet style.
 */
1618
int sock_common_getsockopt(struct socket *sock, int level, int optname,
L
Linus Torvalds 已提交
1619
				  char __user *optval, int __user *optlen);
1620 1621
int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
			int flags);
1622
int sock_common_setsockopt(struct socket *sock, int level, int optname,
1623
				  char __user *optval, unsigned int optlen);
1624
int compat_sock_common_getsockopt(struct socket *sock, int level,
1625
		int optname, char __user *optval, int __user *optlen);
1626
int compat_sock_common_setsockopt(struct socket *sock, int level,
1627
		int optname, char __user *optval, unsigned int optlen);
L
Linus Torvalds 已提交
1628

1629
void sk_common_release(struct sock *sk);
L
Linus Torvalds 已提交
1630 1631 1632 1633

/*
 *	Default socket callbacks and setup code
 */
E
Eric Dumazet 已提交
1634

L
Linus Torvalds 已提交
1635
/* Initialise core socket variables */
1636
void sock_init_data(struct socket *sock, struct sock *sk);
L
Linus Torvalds 已提交
1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665

/*
 * 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)
{
1666
	if (refcount_dec_and_test(&sk->sk_refcnt))
L
Linus Torvalds 已提交
1667 1668
		sk_free(sk);
}
E
Eric Dumazet 已提交
1669
/* Generic version of sock_put(), dealing with all sockets
1670
 * (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...)
E
Eric Dumazet 已提交
1671 1672
 */
void sock_gen_put(struct sock *sk);
L
Linus Torvalds 已提交
1673

1674
int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested,
1675
		     unsigned int trim_cap, bool refcounted);
1676 1677 1678
static inline int sk_receive_skb(struct sock *sk, struct sk_buff *skb,
				 const int nested)
{
1679
	return __sk_receive_skb(sk, skb, nested, 1, true);
1680
}
1681

K
Krishna Kumar 已提交
1682 1683
static inline void sk_tx_queue_set(struct sock *sk, int tx_queue)
{
1684 1685 1686
	/* sk_tx_queue_mapping accept only upto a 16-bit value */
	if (WARN_ON_ONCE((unsigned short)tx_queue >= USHRT_MAX))
		return;
K
Krishna Kumar 已提交
1687 1688 1689
	sk->sk_tx_queue_mapping = tx_queue;
}

1690 1691
#define NO_QUEUE_MAPPING	USHRT_MAX

K
Krishna Kumar 已提交
1692 1693
static inline void sk_tx_queue_clear(struct sock *sk)
{
1694
	sk->sk_tx_queue_mapping = NO_QUEUE_MAPPING;
K
Krishna Kumar 已提交
1695 1696 1697 1698
}

static inline int sk_tx_queue_get(const struct sock *sk)
{
1699 1700 1701 1702
	if (sk && sk->sk_tx_queue_mapping != NO_QUEUE_MAPPING)
		return sk->sk_tx_queue_mapping;

	return -1;
K
Krishna Kumar 已提交
1703 1704
}

1705 1706
static inline void sk_set_socket(struct sock *sk, struct socket *sock)
{
K
Krishna Kumar 已提交
1707
	sk_tx_queue_clear(sk);
1708 1709 1710
	sk->sk_socket = sock;
}

E
Eric Dumazet 已提交
1711 1712
static inline wait_queue_head_t *sk_sleep(struct sock *sk)
{
1713 1714
	BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0);
	return &rcu_dereference_raw(sk->sk_wq)->wait;
E
Eric Dumazet 已提交
1715
}
L
Linus Torvalds 已提交
1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726
/* 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);
1727
	sk_set_socket(sk, NULL);
1728
	sk->sk_wq  = NULL;
L
Linus Torvalds 已提交
1729 1730 1731 1732 1733
	write_unlock_bh(&sk->sk_callback_lock);
}

static inline void sock_graft(struct sock *sk, struct socket *parent)
{
1734
	WARN_ON(parent->sk);
L
Linus Torvalds 已提交
1735
	write_lock_bh(&sk->sk_callback_lock);
1736
	sk->sk_wq = parent->wq;
L
Linus Torvalds 已提交
1737
	parent->sk = sk;
1738
	sk_set_socket(sk, parent);
1739
	sk->sk_uid = SOCK_INODE(parent)->i_uid;
1740
	security_sock_graft(sk, parent);
L
Linus Torvalds 已提交
1741 1742 1743
	write_unlock_bh(&sk->sk_callback_lock);
}

1744 1745
kuid_t sock_i_uid(struct sock *sk);
unsigned long sock_i_ino(struct sock *sk);
L
Linus Torvalds 已提交
1746

1747 1748 1749 1750 1751
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);
}

1752
static inline u32 net_tx_rndhash(void)
1753
{
1754 1755 1756 1757
	u32 v = prandom_u32();

	return v ?: 1;
}
1758

1759 1760 1761
static inline void sk_set_txhash(struct sock *sk)
{
	sk->sk_txhash = net_tx_rndhash();
1762 1763
}

1764 1765 1766 1767 1768 1769
static inline void sk_rethink_txhash(struct sock *sk)
{
	if (sk->sk_txhash)
		sk_set_txhash(sk);
}

L
Linus Torvalds 已提交
1770 1771 1772
static inline struct dst_entry *
__sk_dst_get(struct sock *sk)
{
1773 1774
	return rcu_dereference_check(sk->sk_dst_cache,
				     lockdep_sock_is_held(sk));
L
Linus Torvalds 已提交
1775 1776 1777 1778 1779 1780 1781
}

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

E
Eric Dumazet 已提交
1782 1783
	rcu_read_lock();
	dst = rcu_dereference(sk->sk_dst_cache);
1784 1785
	if (dst && !atomic_inc_not_zero(&dst->__refcnt))
		dst = NULL;
E
Eric Dumazet 已提交
1786
	rcu_read_unlock();
L
Linus Torvalds 已提交
1787 1788 1789
	return dst;
}

E
Eric Dumazet 已提交
1790 1791 1792 1793
static inline void dst_negative_advice(struct sock *sk)
{
	struct dst_entry *ndst, *dst = __sk_dst_get(sk);

1794 1795
	sk_rethink_txhash(sk);

E
Eric Dumazet 已提交
1796 1797 1798 1799 1800
	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
1801
			sk_tx_queue_clear(sk);
1802
			sk->sk_dst_pending_confirm = 0;
E
Eric Dumazet 已提交
1803 1804 1805 1806
		}
	}
}

L
Linus Torvalds 已提交
1807 1808 1809 1810 1811
static inline void
__sk_dst_set(struct sock *sk, struct dst_entry *dst)
{
	struct dst_entry *old_dst;

K
Krishna Kumar 已提交
1812
	sk_tx_queue_clear(sk);
1813
	sk->sk_dst_pending_confirm = 0;
1814 1815
	old_dst = rcu_dereference_protected(sk->sk_dst_cache,
					    lockdep_sock_is_held(sk));
E
Eric Dumazet 已提交
1816
	rcu_assign_pointer(sk->sk_dst_cache, dst);
L
Linus Torvalds 已提交
1817 1818 1819 1820 1821 1822
	dst_release(old_dst);
}

static inline void
sk_dst_set(struct sock *sk, struct dst_entry *dst)
{
1823 1824 1825
	struct dst_entry *old_dst;

	sk_tx_queue_clear(sk);
1826
	sk->sk_dst_pending_confirm = 0;
1827
	old_dst = xchg((__force struct dst_entry **)&sk->sk_dst_cache, dst);
1828
	dst_release(old_dst);
L
Linus Torvalds 已提交
1829 1830 1831 1832 1833
}

static inline void
__sk_dst_reset(struct sock *sk)
{
E
Eric Dumazet 已提交
1834
	__sk_dst_set(sk, NULL);
L
Linus Torvalds 已提交
1835 1836 1837 1838 1839
}

static inline void
sk_dst_reset(struct sock *sk)
{
1840
	sk_dst_set(sk, NULL);
L
Linus Torvalds 已提交
1841 1842
}

1843
struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
L
Linus Torvalds 已提交
1844

1845
struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
L
Linus Torvalds 已提交
1846

1847 1848 1849 1850 1851 1852
static inline void sk_dst_confirm(struct sock *sk)
{
	if (!sk->sk_dst_pending_confirm)
		sk->sk_dst_pending_confirm = 1;
}

1853 1854 1855 1856 1857 1858 1859 1860 1861 1862 1863 1864 1865 1866
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;
	}
}

1867 1868
bool sk_mc_loop(struct sock *sk);

E
Eric Dumazet 已提交
1869
static inline bool sk_can_gso(const struct sock *sk)
1870 1871 1872 1873
{
	return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type);
}

1874
void sk_setup_caps(struct sock *sk, struct dst_entry *dst);
1875

1876
static inline void sk_nocaps_add(struct sock *sk, netdev_features_t flags)
E
Eric Dumazet 已提交
1877 1878 1879 1880 1881
{
	sk->sk_route_nocaps |= flags;
	sk->sk_route_caps &= ~flags;
}

1882
static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
1883
					   struct iov_iter *from, char *to,
1884
					   int copy, int offset)
1885 1886
{
	if (skb->ip_summed == CHECKSUM_NONE) {
1887
		__wsum csum = 0;
1888
		if (!csum_and_copy_from_iter_full(to, copy, &csum, from))
1889
			return -EFAULT;
1890
		skb->csum = csum_block_add(skb->csum, csum, offset);
1891
	} else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
1892
		if (!copy_from_iter_full_nocache(to, copy, from))
1893
			return -EFAULT;
1894
	} else if (!copy_from_iter_full(to, copy, from))
1895 1896 1897 1898 1899 1900
		return -EFAULT;

	return 0;
}

static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
1901
				       struct iov_iter *from, int copy)
1902
{
1903
	int err, offset = skb->len;
1904

1905 1906
	err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy),
				       copy, offset);
1907
	if (err)
1908
		__skb_trim(skb, offset);
1909 1910 1911 1912

	return err;
}

1913
static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from,
1914 1915 1916 1917 1918 1919
					   struct sk_buff *skb,
					   struct page *page,
					   int off, int copy)
{
	int err;

1920 1921
	err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off,
				       copy, skb->len);
1922 1923 1924 1925 1926 1927 1928 1929 1930 1931 1932
	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;
}

1933 1934 1935 1936 1937 1938 1939 1940
/**
 * 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)
{
1941
	return refcount_read(&sk->sk_wmem_alloc) - 1;
1942 1943 1944 1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960
}

/**
 * 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
1961
static inline bool sk_has_allocations(const struct sock *sk)
1962 1963 1964 1965
{
	return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk);
}

1966
/**
H
Herbert Xu 已提交
1967
 * skwq_has_sleeper - check if there are any waiting processes
R
Randy Dunlap 已提交
1968
 * @wq: struct socket_wq
1969
 *
1970
 * Returns true if socket_wq has waiting processes
1971
 *
H
Herbert Xu 已提交
1972
 * The purpose of the skwq_has_sleeper and sock_poll_wait is to wrap the memory
1973 1974
 * barrier call. They were added due to the race found within the tcp code.
 *
1975
 * Consider following tcp code paths::
1976
 *
1977 1978
 *   CPU1                CPU2
 *   sys_select          receive packet
1979 1980 1981 1982 1983
 *   ...                 ...
 *   __add_wait_queue    update tp->rcv_nxt
 *   ...                 ...
 *   tp->rcv_nxt check   sock_def_readable
 *   ...                 {
1984 1985 1986 1987
 *   schedule               rcu_read_lock();
 *                          wq = rcu_dereference(sk->sk_wq);
 *                          if (wq && waitqueue_active(&wq->wait))
 *                              wake_up_interruptible(&wq->wait)
1988 1989 1990 1991 1992 1993 1994
 *                          ...
 *                       }
 *
 * 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.
1995
 *
1996
 */
H
Herbert Xu 已提交
1997
static inline bool skwq_has_sleeper(struct socket_wq *wq)
1998
{
H
Herbert Xu 已提交
1999
	return wq && wq_has_sleeper(&wq->wait);
2000 2001 2002 2003 2004 2005 2006 2007
}

/**
 * sock_poll_wait - place memory barrier behind the poll_wait call.
 * @filp:           file
 * @wait_address:   socket wait queue
 * @p:              poll_table
 *
2008
 * See the comments in the wq_has_sleeper function.
2009 2010 2011 2012
 */
static inline void sock_poll_wait(struct file *filp,
		wait_queue_head_t *wait_address, poll_table *p)
{
2013
	if (!poll_does_not_wait(p) && wait_address) {
2014
		poll_wait(filp, wait_address, p);
E
Eric Dumazet 已提交
2015
		/* We need to be sure we are in sync with the
2016 2017
		 * socket flags modification.
		 *
2018
		 * This memory barrier is paired in the wq_has_sleeper.
E
Eric Dumazet 已提交
2019
		 */
2020 2021 2022 2023
		smp_mb();
	}
}

2024 2025 2026 2027 2028 2029 2030 2031
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;
	}
}

2032 2033
void skb_set_owner_w(struct sk_buff *skb, struct sock *sk);

L
Linus Torvalds 已提交
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/*
E
Eric Dumazet 已提交
2035
 *	Queue a received datagram if it will fit. Stream and sequenced
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2036 2037 2038
 *	protocols can't normally use this as they need to fit buffers in
 *	and play with them.
 *
E
Eric Dumazet 已提交
2039
 *	Inlined as it's very short and called for pretty much every
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Linus Torvalds 已提交
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 *	packet ever received.
 */
static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
{
2044
	skb_orphan(skb);
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2045 2046 2047
	skb->sk = sk;
	skb->destructor = sock_rfree;
	atomic_add(skb->truesize, &sk->sk_rmem_alloc);
2048
	sk_mem_charge(sk, skb->truesize);
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}

2051 2052
void sk_reset_timer(struct sock *sk, struct timer_list *timer,
		    unsigned long expires);
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2054
void sk_stop_timer(struct sock *sk, struct timer_list *timer);
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2056 2057
int __sk_queue_drop_skb(struct sock *sk, struct sk_buff_head *sk_queue,
			struct sk_buff *skb, unsigned int flags,
2058 2059
			void (*destructor)(struct sock *sk,
					   struct sk_buff *skb));
2060
int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
2061
int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
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Linus Torvalds 已提交
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2063
int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
2064
struct sk_buff *sock_dequeue_err_skb(struct sock *sk);
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/*
 *	Recover an error report and clear atomically
 */
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static inline int sock_error(struct sock *sk)
{
2072 2073 2074 2075
	int err;
	if (likely(!sk->sk_err))
		return 0;
	err = xchg(&sk->sk_err, 0);
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	return -err;
}

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

	if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
2084
		amt = sk->sk_sndbuf - refcount_read(&sk->sk_wmem_alloc);
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		if (amt < 0)
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			amt = 0;
	}
	return amt;
}

2091 2092 2093 2094
/* Note:
 *  We use sk->sk_wq_raw, from contexts knowing this
 *  pointer is not NULL and cannot disappear/change.
 */
2095
static inline void sk_set_bit(int nr, struct sock *sk)
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{
2097 2098
	if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
	    !sock_flag(sk, SOCK_FASYNC))
2099 2100
		return;

2101
	set_bit(nr, &sk->sk_wq_raw->flags);
2102 2103 2104 2105
}

static inline void sk_clear_bit(int nr, struct sock *sk)
{
2106 2107
	if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
	    !sock_flag(sk, SOCK_FASYNC))
2108 2109
		return;

2110
	clear_bit(nr, &sk->sk_wq_raw->flags);
2111 2112
}

2113
static inline void sk_wake_async(const struct sock *sk, int how, int band)
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{
2115 2116 2117 2118 2119
	if (sock_flag(sk, SOCK_FASYNC)) {
		rcu_read_lock();
		sock_wake_async(rcu_dereference(sk->sk_wq), how, band);
		rcu_read_unlock();
	}
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}

2122 2123 2124 2125
/* 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.
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 */
2127
#define TCP_SKB_MIN_TRUESIZE	(2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff)))
2128 2129 2130

#define SOCK_MIN_SNDBUF		(TCP_SKB_MIN_TRUESIZE * 2)
#define SOCK_MIN_RCVBUF		 TCP_SKB_MIN_TRUESIZE
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static inline void sk_stream_moderate_sndbuf(struct sock *sk)
{
	if (!(sk->sk_userlocks & SOCK_SNDBUF_LOCK)) {
2135
		sk->sk_sndbuf = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
2136
		sk->sk_sndbuf = max_t(u32, sk->sk_sndbuf, SOCK_MIN_SNDBUF);
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	}
}

2140 2141
struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp,
				    bool force_schedule);
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2143 2144 2145 2146 2147 2148 2149 2150
/**
 * 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)
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{
2152
	if (gfpflags_allow_blocking(sk->sk_allocation))
2153
		return &current->task_frag;
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2154

2155
	return &sk->sk_frag;
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2156 2157
}

2158
bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag);
2159

2160
int sk_alloc_sg(struct sock *sk, int len, struct scatterlist *sg,
2161
		int sg_start, int *sg_curr, unsigned int *sg_size,
2162 2163
		int first_coalesce);

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/*
 *	Default write policy as shown to user space via poll/select/SIGIO
 */
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2167
static inline bool sock_writeable(const struct sock *sk)
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{
2169
	return refcount_read(&sk->sk_wmem_alloc) < (sk->sk_sndbuf >> 1);
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2170 2171
}

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static inline gfp_t gfp_any(void)
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2173
{
2174
	return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
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2175 2176
}

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2177
static inline long sock_rcvtimeo(const struct sock *sk, bool noblock)
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2178 2179 2180 2181
{
	return noblock ? 0 : sk->sk_rcvtimeo;
}

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static inline long sock_sndtimeo(const struct sock *sk, bool noblock)
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2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193 2194 2195 2196 2197 2198 2199
{
	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;
}

2200 2201 2202 2203 2204 2205 2206 2207 2208 2209 2210 2211 2212 2213
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))

2214
#define sock_skb_cb_check_size(size) \
2215
	BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET)
2216

2217 2218 2219
static inline void
sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb)
{
2220 2221
	SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, SOCK_RXQ_OVFL) ?
						atomic_read(&sk->sk_drops) : 0;
2222 2223
}

2224 2225 2226 2227 2228 2229 2230
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);
}

2231 2232 2233 2234
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);
2235

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2236
static inline void
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2237 2238
sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
{
2239
	ktime_t kt = skb->tstamp;
2240
	struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
2241

2242 2243
	/*
	 * generate control messages if
2244
	 * - receive time stamping in software requested
2245 2246 2247 2248
	 * - software time stamp available and wanted
	 * - hardware time stamps available and wanted
	 */
	if (sock_flag(sk, SOCK_RCVTSTAMP) ||
2249
	    (sk->sk_tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) ||
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	    (kt && sk->sk_tsflags & SOF_TIMESTAMPING_SOFTWARE) ||
	    (hwtstamps->hwtstamp &&
2252
	     (sk->sk_tsflags & SOF_TIMESTAMPING_RAW_HARDWARE)))
2253 2254
		__sock_recv_timestamp(msg, sk, skb);
	else
2255
		sk->sk_stamp = kt;
2256 2257 2258

	if (sock_flag(sk, SOCK_WIFI_STATUS) && skb->wifi_acked_valid)
		__sock_recv_wifi_status(msg, sk, skb);
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}

2261 2262
void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
			      struct sk_buff *skb);
2263

2264
#define SK_DEFAULT_STAMP (-1L * NSEC_PER_SEC)
2265 2266 2267 2268
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)			| \
2269 2270 2271
			   (1UL << SOCK_RCVTSTAMP))
#define TSFLAGS_ANY	  (SOF_TIMESTAMPING_SOFTWARE			| \
			   SOF_TIMESTAMPING_RAW_HARDWARE)
2272

2273
	if (sk->sk_flags & FLAGS_TS_OR_DROPS || sk->sk_tsflags & TSFLAGS_ANY)
2274
		__sock_recv_ts_and_drops(msg, sk, skb);
2275
	else if (unlikely(sock_flag(sk, SOCK_TIMESTAMP)))
2276
		sk->sk_stamp = skb->tstamp;
2277 2278
	else if (unlikely(sk->sk_stamp == SK_DEFAULT_STAMP))
		sk->sk_stamp = 0;
2279
}
2280

2281
void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags);
2282

2283 2284 2285
/**
 * sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
 * @sk:		socket sending this packet
2286
 * @tsflags:	timestamping flags to use
2287 2288
 * @tx_flags:	completed with instructions for time stamping
 *
2289
 * Note: callers should take care of initial ``*tx_flags`` value (usually 0)
2290
 */
2291 2292
static inline void sock_tx_timestamp(const struct sock *sk, __u16 tsflags,
				     __u8 *tx_flags)
2293
{
2294 2295
	if (unlikely(tsflags))
		__sock_tx_timestamp(tsflags, tx_flags);
2296 2297 2298
	if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS)))
		*tx_flags |= SKBTX_WIFI_STATUS;
}
2299

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2300 2301
/**
 * sk_eat_skb - Release a skb if it is no longer needed
2302 2303
 * @sk: socket to eat this skb from
 * @skb: socket buffer to eat
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2304 2305 2306 2307
 *
 * This routine must be called with interrupts disabled or with the socket
 * locked so that the sk_buff queue operation is ok.
*/
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2308
static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb)
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2309 2310 2311 2312 2313
{
	__skb_unlink(skb, &sk->sk_receive_queue);
	__kfree_skb(skb);
}

2314 2315 2316
static inline
struct net *sock_net(const struct sock *sk)
{
E
Eric Dumazet 已提交
2317
	return read_pnet(&sk->sk_net);
2318 2319 2320
}

static inline
2321
void sock_net_set(struct sock *sk, struct net *net)
2322
{
E
Eric Dumazet 已提交
2323
	write_pnet(&sk->sk_net, net);
2324 2325
}

2326 2327
static inline struct sock *skb_steal_sock(struct sk_buff *skb)
{
2328
	if (skb->sk) {
2329 2330 2331 2332 2333 2334 2335 2336 2337
		struct sock *sk = skb->sk;

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

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2338 2339 2340 2341 2342 2343 2344 2345
/* 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);
}

2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356 2357 2358 2359 2360 2361
/* Checks if this SKB belongs to an HW offloaded socket
 * and whether any SW fallbacks are required based on dev.
 */
static inline struct sk_buff *sk_validate_xmit_skb(struct sk_buff *skb,
						   struct net_device *dev)
{
#ifdef CONFIG_SOCK_VALIDATE_XMIT
	struct sock *sk = skb->sk;

	if (sk && sk_fullsock(sk) && sk->sk_validate_xmit_skb)
		skb = sk->sk_validate_xmit_skb(sk, dev, skb);
#endif

	return skb;
}

2362 2363 2364 2365 2366 2367 2368 2369
/* 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);
}

2370 2371 2372 2373 2374
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);
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2376 2377 2378 2379 2380
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);

2381 2382
void sk_get_meminfo(const struct sock *sk, u32 *meminfo);

2383 2384 2385 2386 2387 2388 2389 2390 2391 2392
/* 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)

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2393 2394 2395
extern __u32 sysctl_wmem_max;
extern __u32 sysctl_rmem_max;

2396
extern int sysctl_tstamp_allow_data;
2397 2398
extern int sysctl_optmem_max;

2399 2400 2401
extern __u32 sysctl_wmem_default;
extern __u32 sysctl_rmem_default;

2402 2403 2404 2405 2406 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416 2417 2418 2419
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;
}

2420 2421 2422 2423 2424 2425 2426 2427 2428 2429 2430
/* 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;
}

2431 2432 2433 2434 2435 2436 2437 2438 2439 2440 2441 2442 2443 2444 2445 2446 2447 2448 2449
/* 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;
}

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2450
#endif	/* _SOCK_H */