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v5.14.15
   1/* SPDX-License-Identifier: GPL-2.0-or-later */
   2/*
   3 * INET		An implementation of the TCP/IP protocol suite for the LINUX
   4 *		operating system.  INET is implemented using the  BSD Socket
   5 *		interface as the means of communication with the user level.
   6 *
   7 *		Definitions for the AF_INET socket handler.
   8 *
   9 * Version:	@(#)sock.h	1.0.4	05/13/93
  10 *
  11 * Authors:	Ross Biro
  12 *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
  13 *		Corey Minyard <wf-rch!minyard@relay.EU.net>
  14 *		Florian La Roche <flla@stud.uni-sb.de>
  15 *
  16 * Fixes:
  17 *		Alan Cox	:	Volatiles in skbuff pointers. See
  18 *					skbuff comments. May be overdone,
  19 *					better to prove they can be removed
  20 *					than the reverse.
  21 *		Alan Cox	:	Added a zapped field for tcp to note
  22 *					a socket is reset and must stay shut up
  23 *		Alan Cox	:	New fields for options
  24 *	Pauline Middelink	:	identd support
  25 *		Alan Cox	:	Eliminate low level recv/recvfrom
  26 *		David S. Miller	:	New socket lookup architecture.
  27 *              Steve Whitehouse:       Default routines for sock_ops
  28 *              Arnaldo C. Melo :	removed net_pinfo, tp_pinfo and made
  29 *              			protinfo be just a void pointer, as the
  30 *              			protocol specific parts were moved to
  31 *              			respective headers and ipv4/v6, etc now
  32 *              			use private slabcaches for its socks
  33 *              Pedro Hortas	:	New flags field for socket options
 
 
 
 
 
 
  34 */
  35#ifndef _SOCK_H
  36#define _SOCK_H
  37
  38#include <linux/hardirq.h>
  39#include <linux/kernel.h>
  40#include <linux/list.h>
  41#include <linux/list_nulls.h>
  42#include <linux/timer.h>
  43#include <linux/cache.h>
  44#include <linux/bitops.h>
  45#include <linux/lockdep.h>
  46#include <linux/netdevice.h>
  47#include <linux/skbuff.h>	/* struct sk_buff */
  48#include <linux/mm.h>
  49#include <linux/security.h>
  50#include <linux/slab.h>
  51#include <linux/uaccess.h>
  52#include <linux/page_counter.h>
  53#include <linux/memcontrol.h>
 
  54#include <linux/static_key.h>
 
  55#include <linux/sched.h>
  56#include <linux/wait.h>
  57#include <linux/cgroup-defs.h>
  58#include <linux/rbtree.h>
  59#include <linux/filter.h>
  60#include <linux/rculist_nulls.h>
  61#include <linux/poll.h>
  62#include <linux/sockptr.h>
  63#include <linux/indirect_call_wrapper.h>
  64#include <linux/atomic.h>
  65#include <linux/refcount.h>
  66#include <net/dst.h>
  67#include <net/checksum.h>
  68#include <net/tcp_states.h>
  69#include <linux/net_tstamp.h>
  70#include <net/l3mdev.h>
  71
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  72/*
  73 * This structure really needs to be cleaned up.
  74 * Most of it is for TCP, and not used by any of
  75 * the other protocols.
  76 */
  77
  78/* Define this to get the SOCK_DBG debugging facility. */
  79#define SOCK_DEBUGGING
  80#ifdef SOCK_DEBUGGING
  81#define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \
  82					printk(KERN_DEBUG msg); } while (0)
  83#else
  84/* Validate arguments and do nothing */
  85static inline __printf(2, 3)
  86void SOCK_DEBUG(const struct sock *sk, const char *msg, ...)
  87{
  88}
  89#endif
  90
  91/* This is the per-socket lock.  The spinlock provides a synchronization
  92 * between user contexts and software interrupt processing, whereas the
  93 * mini-semaphore synchronizes multiple users amongst themselves.
  94 */
  95typedef struct {
  96	spinlock_t		slock;
  97	int			owned;
  98	wait_queue_head_t	wq;
  99	/*
 100	 * We express the mutex-alike socket_lock semantics
 101	 * to the lock validator by explicitly managing
 102	 * the slock as a lock variant (in addition to
 103	 * the slock itself):
 104	 */
 105#ifdef CONFIG_DEBUG_LOCK_ALLOC
 106	struct lockdep_map dep_map;
 107#endif
 108} socket_lock_t;
 109
 110struct sock;
 111struct proto;
 112struct net;
 113
 114typedef __u32 __bitwise __portpair;
 115typedef __u64 __bitwise __addrpair;
 116
 117/**
 118 *	struct sock_common - minimal network layer representation of sockets
 119 *	@skc_daddr: Foreign IPv4 addr
 120 *	@skc_rcv_saddr: Bound local IPv4 addr
 121 *	@skc_addrpair: 8-byte-aligned __u64 union of @skc_daddr & @skc_rcv_saddr
 122 *	@skc_hash: hash value used with various protocol lookup tables
 123 *	@skc_u16hashes: two u16 hash values used by UDP lookup tables
 124 *	@skc_dport: placeholder for inet_dport/tw_dport
 125 *	@skc_num: placeholder for inet_num/tw_num
 126 *	@skc_portpair: __u32 union of @skc_dport & @skc_num
 127 *	@skc_family: network address family
 128 *	@skc_state: Connection state
 129 *	@skc_reuse: %SO_REUSEADDR setting
 130 *	@skc_reuseport: %SO_REUSEPORT setting
 131 *	@skc_ipv6only: socket is IPV6 only
 132 *	@skc_net_refcnt: socket is using net ref counting
 133 *	@skc_bound_dev_if: bound device index if != 0
 134 *	@skc_bind_node: bind hash linkage for various protocol lookup tables
 135 *	@skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol
 136 *	@skc_prot: protocol handlers inside a network family
 137 *	@skc_net: reference to the network namespace of this socket
 138 *	@skc_v6_daddr: IPV6 destination address
 139 *	@skc_v6_rcv_saddr: IPV6 source address
 140 *	@skc_cookie: socket's cookie value
 141 *	@skc_node: main hash linkage for various protocol lookup tables
 142 *	@skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol
 143 *	@skc_tx_queue_mapping: tx queue number for this connection
 144 *	@skc_rx_queue_mapping: rx queue number for this connection
 145 *	@skc_flags: place holder for sk_flags
 146 *		%SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE,
 147 *		%SO_OOBINLINE settings, %SO_TIMESTAMPING settings
 148 *	@skc_listener: connection request listener socket (aka rsk_listener)
 149 *		[union with @skc_flags]
 150 *	@skc_tw_dr: (aka tw_dr) ptr to &struct inet_timewait_death_row
 151 *		[union with @skc_flags]
 152 *	@skc_incoming_cpu: record/match cpu processing incoming packets
 153 *	@skc_rcv_wnd: (aka rsk_rcv_wnd) TCP receive window size (possibly scaled)
 154 *		[union with @skc_incoming_cpu]
 155 *	@skc_tw_rcv_nxt: (aka tw_rcv_nxt) TCP window next expected seq number
 156 *		[union with @skc_incoming_cpu]
 157 *	@skc_refcnt: reference count
 158 *
 159 *	This is the minimal network layer representation of sockets, the header
 160 *	for struct sock and struct inet_timewait_sock.
 161 */
 162struct sock_common {
 163	/* skc_daddr and skc_rcv_saddr must be grouped on a 8 bytes aligned
 164	 * address on 64bit arches : cf INET_MATCH()
 165	 */
 166	union {
 167		__addrpair	skc_addrpair;
 168		struct {
 169			__be32	skc_daddr;
 170			__be32	skc_rcv_saddr;
 171		};
 172	};
 173	union  {
 174		unsigned int	skc_hash;
 175		__u16		skc_u16hashes[2];
 176	};
 177	/* skc_dport && skc_num must be grouped as well */
 178	union {
 179		__portpair	skc_portpair;
 180		struct {
 181			__be16	skc_dport;
 182			__u16	skc_num;
 183		};
 184	};
 185
 186	unsigned short		skc_family;
 187	volatile unsigned char	skc_state;
 188	unsigned char		skc_reuse:4;
 189	unsigned char		skc_reuseport:1;
 190	unsigned char		skc_ipv6only:1;
 191	unsigned char		skc_net_refcnt:1;
 192	int			skc_bound_dev_if;
 193	union {
 194		struct hlist_node	skc_bind_node;
 195		struct hlist_node	skc_portaddr_node;
 196	};
 197	struct proto		*skc_prot;
 198	possible_net_t		skc_net;
 199
 200#if IS_ENABLED(CONFIG_IPV6)
 201	struct in6_addr		skc_v6_daddr;
 202	struct in6_addr		skc_v6_rcv_saddr;
 203#endif
 204
 205	atomic64_t		skc_cookie;
 206
 207	/* following fields are padding to force
 208	 * offset(struct sock, sk_refcnt) == 128 on 64bit arches
 209	 * assuming IPV6 is enabled. We use this padding differently
 210	 * for different kind of 'sockets'
 211	 */
 212	union {
 213		unsigned long	skc_flags;
 214		struct sock	*skc_listener; /* request_sock */
 215		struct inet_timewait_death_row *skc_tw_dr; /* inet_timewait_sock */
 216	};
 217	/*
 218	 * fields between dontcopy_begin/dontcopy_end
 219	 * are not copied in sock_copy()
 220	 */
 221	/* private: */
 222	int			skc_dontcopy_begin[0];
 223	/* public: */
 224	union {
 225		struct hlist_node	skc_node;
 226		struct hlist_nulls_node skc_nulls_node;
 227	};
 228	unsigned short		skc_tx_queue_mapping;
 229#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
 230	unsigned short		skc_rx_queue_mapping;
 231#endif
 232	union {
 233		int		skc_incoming_cpu;
 234		u32		skc_rcv_wnd;
 235		u32		skc_tw_rcv_nxt; /* struct tcp_timewait_sock  */
 236	};
 237
 238	refcount_t		skc_refcnt;
 239	/* private: */
 240	int                     skc_dontcopy_end[0];
 241	union {
 242		u32		skc_rxhash;
 243		u32		skc_window_clamp;
 244		u32		skc_tw_snd_nxt; /* struct tcp_timewait_sock */
 245	};
 246	/* public: */
 247};
 248
 249struct bpf_local_storage;
 250
 251/**
 252  *	struct sock - network layer representation of sockets
 253  *	@__sk_common: shared layout with inet_timewait_sock
 254  *	@sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
 255  *	@sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
 256  *	@sk_lock:	synchronizer
 257  *	@sk_kern_sock: True if sock is using kernel lock classes
 258  *	@sk_rcvbuf: size of receive buffer in bytes
 259  *	@sk_wq: sock wait queue and async head
 260  *	@sk_rx_dst: receive input route used by early demux
 261  *	@sk_dst_cache: destination cache
 262  *	@sk_dst_pending_confirm: need to confirm neighbour
 263  *	@sk_policy: flow policy
 264  *	@sk_rx_skb_cache: cache copy of recently accessed RX skb
 265  *	@sk_receive_queue: incoming packets
 266  *	@sk_wmem_alloc: transmit queue bytes committed
 267  *	@sk_tsq_flags: TCP Small Queues flags
 268  *	@sk_write_queue: Packet sending queue
 
 269  *	@sk_omem_alloc: "o" is "option" or "other"
 270  *	@sk_wmem_queued: persistent queue size
 271  *	@sk_forward_alloc: space allocated forward
 272  *	@sk_napi_id: id of the last napi context to receive data for sk
 273  *	@sk_ll_usec: usecs to busypoll when there is no data
 274  *	@sk_allocation: allocation mode
 275  *	@sk_pacing_rate: Pacing rate (if supported by transport/packet scheduler)
 276  *	@sk_pacing_status: Pacing status (requested, handled by sch_fq)
 277  *	@sk_max_pacing_rate: Maximum pacing rate (%SO_MAX_PACING_RATE)
 278  *	@sk_sndbuf: size of send buffer in bytes
 279  *	@__sk_flags_offset: empty field used to determine location of bitfield
 280  *	@sk_padding: unused element for alignment
 281  *	@sk_no_check_tx: %SO_NO_CHECK setting, set checksum in TX packets
 282  *	@sk_no_check_rx: allow zero checksum in RX packets
 283  *	@sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
 284  *	@sk_route_nocaps: forbidden route capabilities (e.g NETIF_F_GSO_MASK)
 285  *	@sk_route_forced_caps: static, forced route capabilities
 286  *		(set in tcp_init_sock())
 287  *	@sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
 288  *	@sk_gso_max_size: Maximum GSO segment size to build
 289  *	@sk_gso_max_segs: Maximum number of GSO segments
 290  *	@sk_pacing_shift: scaling factor for TCP Small Queues
 291  *	@sk_lingertime: %SO_LINGER l_linger setting
 292  *	@sk_backlog: always used with the per-socket spinlock held
 293  *	@sk_callback_lock: used with the callbacks in the end of this struct
 294  *	@sk_error_queue: rarely used
 295  *	@sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt,
 296  *			  IPV6_ADDRFORM for instance)
 297  *	@sk_err: last error
 298  *	@sk_err_soft: errors that don't cause failure but are the cause of a
 299  *		      persistent failure not just 'timed out'
 300  *	@sk_drops: raw/udp drops counter
 301  *	@sk_ack_backlog: current listen backlog
 302  *	@sk_max_ack_backlog: listen backlog set in listen()
 303  *	@sk_uid: user id of owner
 304  *	@sk_prefer_busy_poll: prefer busypolling over softirq processing
 305  *	@sk_busy_poll_budget: napi processing budget when busypolling
 306  *	@sk_priority: %SO_PRIORITY setting
 
 307  *	@sk_type: socket type (%SOCK_STREAM, etc)
 308  *	@sk_protocol: which protocol this socket belongs in this network family
 309  *	@sk_peer_pid: &struct pid for this socket's peer
 310  *	@sk_peer_cred: %SO_PEERCRED setting
 311  *	@sk_rcvlowat: %SO_RCVLOWAT setting
 312  *	@sk_rcvtimeo: %SO_RCVTIMEO setting
 313  *	@sk_sndtimeo: %SO_SNDTIMEO setting
 314  *	@sk_txhash: computed flow hash for use on transmit
 315  *	@sk_filter: socket filtering instructions
 
 316  *	@sk_timer: sock cleanup timer
 317  *	@sk_stamp: time stamp of last packet received
 318  *	@sk_stamp_seq: lock for accessing sk_stamp on 32 bit architectures only
 319  *	@sk_tsflags: SO_TIMESTAMPING flags
 320  *	@sk_bind_phc: SO_TIMESTAMPING bind PHC index of PTP virtual clock
 321  *	              for timestamping
 322  *	@sk_tskey: counter to disambiguate concurrent tstamp requests
 323  *	@sk_zckey: counter to order MSG_ZEROCOPY notifications
 324  *	@sk_socket: Identd and reporting IO signals
 325  *	@sk_user_data: RPC layer private data
 326  *	@sk_frag: cached page frag
 
 327  *	@sk_peek_off: current peek_offset value
 328  *	@sk_send_head: front of stuff to transmit
 329  *	@tcp_rtx_queue: TCP re-transmit queue [union with @sk_send_head]
 330  *	@sk_tx_skb_cache: cache copy of recently accessed TX skb
 331  *	@sk_security: used by security modules
 332  *	@sk_mark: generic packet mark
 333  *	@sk_cgrp_data: cgroup data for this cgroup
 334  *	@sk_memcg: this socket's memory cgroup association
 335  *	@sk_write_pending: a write to stream socket waits to start
 336  *	@sk_state_change: callback to indicate change in the state of the sock
 337  *	@sk_data_ready: callback to indicate there is data to be processed
 338  *	@sk_write_space: callback to indicate there is bf sending space available
 339  *	@sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
 340  *	@sk_backlog_rcv: callback to process the backlog
 341  *	@sk_validate_xmit_skb: ptr to an optional validate function
 342  *	@sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
 343  *	@sk_reuseport_cb: reuseport group container
 344  *	@sk_bpf_storage: ptr to cache and control for bpf_sk_storage
 345  *	@sk_rcu: used during RCU grace period
 346  *	@sk_clockid: clockid used by time-based scheduling (SO_TXTIME)
 347  *	@sk_txtime_deadline_mode: set deadline mode for SO_TXTIME
 348  *	@sk_txtime_report_errors: set report errors mode for SO_TXTIME
 349  *	@sk_txtime_unused: unused txtime flags
 350  */
 351struct sock {
 352	/*
 353	 * Now struct inet_timewait_sock also uses sock_common, so please just
 354	 * don't add nothing before this first member (__sk_common) --acme
 355	 */
 356	struct sock_common	__sk_common;
 357#define sk_node			__sk_common.skc_node
 358#define sk_nulls_node		__sk_common.skc_nulls_node
 359#define sk_refcnt		__sk_common.skc_refcnt
 360#define sk_tx_queue_mapping	__sk_common.skc_tx_queue_mapping
 361#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
 362#define sk_rx_queue_mapping	__sk_common.skc_rx_queue_mapping
 363#endif
 364
 365#define sk_dontcopy_begin	__sk_common.skc_dontcopy_begin
 366#define sk_dontcopy_end		__sk_common.skc_dontcopy_end
 367#define sk_hash			__sk_common.skc_hash
 368#define sk_portpair		__sk_common.skc_portpair
 369#define sk_num			__sk_common.skc_num
 370#define sk_dport		__sk_common.skc_dport
 371#define sk_addrpair		__sk_common.skc_addrpair
 372#define sk_daddr		__sk_common.skc_daddr
 373#define sk_rcv_saddr		__sk_common.skc_rcv_saddr
 374#define sk_family		__sk_common.skc_family
 375#define sk_state		__sk_common.skc_state
 376#define sk_reuse		__sk_common.skc_reuse
 377#define sk_reuseport		__sk_common.skc_reuseport
 378#define sk_ipv6only		__sk_common.skc_ipv6only
 379#define sk_net_refcnt		__sk_common.skc_net_refcnt
 380#define sk_bound_dev_if		__sk_common.skc_bound_dev_if
 381#define sk_bind_node		__sk_common.skc_bind_node
 382#define sk_prot			__sk_common.skc_prot
 383#define sk_net			__sk_common.skc_net
 384#define sk_v6_daddr		__sk_common.skc_v6_daddr
 385#define sk_v6_rcv_saddr	__sk_common.skc_v6_rcv_saddr
 386#define sk_cookie		__sk_common.skc_cookie
 387#define sk_incoming_cpu		__sk_common.skc_incoming_cpu
 388#define sk_flags		__sk_common.skc_flags
 389#define sk_rxhash		__sk_common.skc_rxhash
 390
 391	socket_lock_t		sk_lock;
 392	atomic_t		sk_drops;
 393	int			sk_rcvlowat;
 394	struct sk_buff_head	sk_error_queue;
 395	struct sk_buff		*sk_rx_skb_cache;
 396	struct sk_buff_head	sk_receive_queue;
 397	/*
 398	 * The backlog queue is special, it is always used with
 399	 * the per-socket spinlock held and requires low latency
 400	 * access. Therefore we special case it's implementation.
 401	 * Note : rmem_alloc is in this structure to fill a hole
 402	 * on 64bit arches, not because its logically part of
 403	 * backlog.
 404	 */
 405	struct {
 406		atomic_t	rmem_alloc;
 407		int		len;
 408		struct sk_buff	*head;
 409		struct sk_buff	*tail;
 410	} sk_backlog;
 411#define sk_rmem_alloc sk_backlog.rmem_alloc
 412
 413	int			sk_forward_alloc;
 414#ifdef CONFIG_NET_RX_BUSY_POLL
 415	unsigned int		sk_ll_usec;
 416	/* ===== mostly read cache line ===== */
 417	unsigned int		sk_napi_id;
 418#endif
 
 419	int			sk_rcvbuf;
 420
 421	struct sk_filter __rcu	*sk_filter;
 422	union {
 423		struct socket_wq __rcu	*sk_wq;
 424		/* private: */
 425		struct socket_wq	*sk_wq_raw;
 426		/* public: */
 427	};
 428#ifdef CONFIG_XFRM
 429	struct xfrm_policy __rcu *sk_policy[2];
 430#endif
 431	struct dst_entry	*sk_rx_dst;
 432	struct dst_entry __rcu	*sk_dst_cache;
 
 
 433	atomic_t		sk_omem_alloc;
 434	int			sk_sndbuf;
 435
 436	/* ===== cache line for TX ===== */
 437	int			sk_wmem_queued;
 438	refcount_t		sk_wmem_alloc;
 439	unsigned long		sk_tsq_flags;
 440	union {
 441		struct sk_buff	*sk_send_head;
 442		struct rb_root	tcp_rtx_queue;
 443	};
 444	struct sk_buff		*sk_tx_skb_cache;
 445	struct sk_buff_head	sk_write_queue;
 446	__s32			sk_peek_off;
 447	int			sk_write_pending;
 448	__u32			sk_dst_pending_confirm;
 449	u32			sk_pacing_status; /* see enum sk_pacing */
 450	long			sk_sndtimeo;
 451	struct timer_list	sk_timer;
 452	__u32			sk_priority;
 453	__u32			sk_mark;
 454	unsigned long		sk_pacing_rate; /* bytes per second */
 455	unsigned long		sk_max_pacing_rate;
 456	struct page_frag	sk_frag;
 457	netdev_features_t	sk_route_caps;
 458	netdev_features_t	sk_route_nocaps;
 459	netdev_features_t	sk_route_forced_caps;
 460	int			sk_gso_type;
 461	unsigned int		sk_gso_max_size;
 462	gfp_t			sk_allocation;
 463	__u32			sk_txhash;
 464
 465	/*
 466	 * Because of non atomicity rules, all
 467	 * changes are protected by socket lock.
 468	 */
 469	u8			sk_padding : 1,
 470				sk_kern_sock : 1,
 471				sk_no_check_tx : 1,
 472				sk_no_check_rx : 1,
 473				sk_userlocks : 4;
 474	u8			sk_pacing_shift;
 475	u16			sk_type;
 476	u16			sk_protocol;
 477	u16			sk_gso_max_segs;
 
 478	unsigned long	        sk_lingertime;
 
 479	struct proto		*sk_prot_creator;
 480	rwlock_t		sk_callback_lock;
 481	int			sk_err,
 482				sk_err_soft;
 483	u32			sk_ack_backlog;
 484	u32			sk_max_ack_backlog;
 485	kuid_t			sk_uid;
 486#ifdef CONFIG_NET_RX_BUSY_POLL
 487	u8			sk_prefer_busy_poll;
 488	u16			sk_busy_poll_budget;
 489#endif
 490	spinlock_t		sk_peer_lock;
 491	struct pid		*sk_peer_pid;
 492	const struct cred	*sk_peer_cred;
 493
 494	long			sk_rcvtimeo;
 
 
 
 495	ktime_t			sk_stamp;
 496#if BITS_PER_LONG==32
 497	seqlock_t		sk_stamp_seq;
 498#endif
 499	u16			sk_tsflags;
 500	int			sk_bind_phc;
 501	u8			sk_shutdown;
 502	u32			sk_tskey;
 503	atomic_t		sk_zckey;
 504
 505	u8			sk_clockid;
 506	u8			sk_txtime_deadline_mode : 1,
 507				sk_txtime_report_errors : 1,
 508				sk_txtime_unused : 6;
 509
 510	struct socket		*sk_socket;
 511	void			*sk_user_data;
 
 
 
 
 
 512#ifdef CONFIG_SECURITY
 513	void			*sk_security;
 514#endif
 515	struct sock_cgroup_data	sk_cgrp_data;
 516	struct mem_cgroup	*sk_memcg;
 
 517	void			(*sk_state_change)(struct sock *sk);
 518	void			(*sk_data_ready)(struct sock *sk);
 519	void			(*sk_write_space)(struct sock *sk);
 520	void			(*sk_error_report)(struct sock *sk);
 521	int			(*sk_backlog_rcv)(struct sock *sk,
 522						  struct sk_buff *skb);
 523#ifdef CONFIG_SOCK_VALIDATE_XMIT
 524	struct sk_buff*		(*sk_validate_xmit_skb)(struct sock *sk,
 525							struct net_device *dev,
 526							struct sk_buff *skb);
 527#endif
 528	void                    (*sk_destruct)(struct sock *sk);
 529	struct sock_reuseport __rcu	*sk_reuseport_cb;
 530#ifdef CONFIG_BPF_SYSCALL
 531	struct bpf_local_storage __rcu	*sk_bpf_storage;
 532#endif
 533	struct rcu_head		sk_rcu;
 534};
 535
 536enum sk_pacing {
 537	SK_PACING_NONE		= 0,
 538	SK_PACING_NEEDED	= 1,
 539	SK_PACING_FQ		= 2,
 540};
 541
 542/* Pointer stored in sk_user_data might not be suitable for copying
 543 * when cloning the socket. For instance, it can point to a reference
 544 * counted object. sk_user_data bottom bit is set if pointer must not
 545 * be copied.
 546 */
 547#define SK_USER_DATA_NOCOPY	1UL
 548#define SK_USER_DATA_BPF	2UL	/* Managed by BPF */
 549#define SK_USER_DATA_PTRMASK	~(SK_USER_DATA_NOCOPY | SK_USER_DATA_BPF)
 550
 551/**
 552 * sk_user_data_is_nocopy - Test if sk_user_data pointer must not be copied
 553 * @sk: socket
 554 */
 555static inline bool sk_user_data_is_nocopy(const struct sock *sk)
 556{
 557	return ((uintptr_t)sk->sk_user_data & SK_USER_DATA_NOCOPY);
 558}
 559
 560#define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data)))
 561
 562#define rcu_dereference_sk_user_data(sk)				\
 563({									\
 564	void *__tmp = rcu_dereference(__sk_user_data((sk)));		\
 565	(void *)((uintptr_t)__tmp & SK_USER_DATA_PTRMASK);		\
 566})
 567#define rcu_assign_sk_user_data(sk, ptr)				\
 568({									\
 569	uintptr_t __tmp = (uintptr_t)(ptr);				\
 570	WARN_ON_ONCE(__tmp & ~SK_USER_DATA_PTRMASK);			\
 571	rcu_assign_pointer(__sk_user_data((sk)), __tmp);		\
 572})
 573#define rcu_assign_sk_user_data_nocopy(sk, ptr)				\
 574({									\
 575	uintptr_t __tmp = (uintptr_t)(ptr);				\
 576	WARN_ON_ONCE(__tmp & ~SK_USER_DATA_PTRMASK);			\
 577	rcu_assign_pointer(__sk_user_data((sk)),			\
 578			   __tmp | SK_USER_DATA_NOCOPY);		\
 579})
 580
 581/*
 582 * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK
 583 * or not whether his port will be reused by someone else. SK_FORCE_REUSE
 584 * on a socket means that the socket will reuse everybody else's port
 585 * without looking at the other's sk_reuse value.
 586 */
 587
 588#define SK_NO_REUSE	0
 589#define SK_CAN_REUSE	1
 590#define SK_FORCE_REUSE	2
 591
 592int sk_set_peek_off(struct sock *sk, int val);
 593
 594static inline int sk_peek_offset(struct sock *sk, int flags)
 595{
 596	if (unlikely(flags & MSG_PEEK)) {
 597		return READ_ONCE(sk->sk_peek_off);
 598	}
 599
 600	return 0;
 601}
 602
 603static inline void sk_peek_offset_bwd(struct sock *sk, int val)
 604{
 605	s32 off = READ_ONCE(sk->sk_peek_off);
 606
 607	if (unlikely(off >= 0)) {
 608		off = max_t(s32, off - val, 0);
 609		WRITE_ONCE(sk->sk_peek_off, off);
 610	}
 611}
 612
 613static inline void sk_peek_offset_fwd(struct sock *sk, int val)
 614{
 615	sk_peek_offset_bwd(sk, -val);
 
 616}
 617
 618/*
 619 * Hashed lists helper routines
 620 */
 621static inline struct sock *sk_entry(const struct hlist_node *node)
 622{
 623	return hlist_entry(node, struct sock, sk_node);
 624}
 625
 626static inline struct sock *__sk_head(const struct hlist_head *head)
 627{
 628	return hlist_entry(head->first, struct sock, sk_node);
 629}
 630
 631static inline struct sock *sk_head(const struct hlist_head *head)
 632{
 633	return hlist_empty(head) ? NULL : __sk_head(head);
 634}
 635
 636static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head)
 637{
 638	return hlist_nulls_entry(head->first, struct sock, sk_nulls_node);
 639}
 640
 641static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head)
 642{
 643	return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head);
 644}
 645
 646static inline struct sock *sk_next(const struct sock *sk)
 647{
 648	return hlist_entry_safe(sk->sk_node.next, struct sock, sk_node);
 
 649}
 650
 651static inline struct sock *sk_nulls_next(const struct sock *sk)
 652{
 653	return (!is_a_nulls(sk->sk_nulls_node.next)) ?
 654		hlist_nulls_entry(sk->sk_nulls_node.next,
 655				  struct sock, sk_nulls_node) :
 656		NULL;
 657}
 658
 659static inline bool sk_unhashed(const struct sock *sk)
 660{
 661	return hlist_unhashed(&sk->sk_node);
 662}
 663
 664static inline bool sk_hashed(const struct sock *sk)
 665{
 666	return !sk_unhashed(sk);
 667}
 668
 669static inline void sk_node_init(struct hlist_node *node)
 670{
 671	node->pprev = NULL;
 672}
 673
 674static inline void sk_nulls_node_init(struct hlist_nulls_node *node)
 675{
 676	node->pprev = NULL;
 677}
 678
 679static inline void __sk_del_node(struct sock *sk)
 680{
 681	__hlist_del(&sk->sk_node);
 682}
 683
 684/* NB: equivalent to hlist_del_init_rcu */
 685static inline bool __sk_del_node_init(struct sock *sk)
 686{
 687	if (sk_hashed(sk)) {
 688		__sk_del_node(sk);
 689		sk_node_init(&sk->sk_node);
 690		return true;
 691	}
 692	return false;
 693}
 694
 695/* Grab socket reference count. This operation is valid only
 696   when sk is ALREADY grabbed f.e. it is found in hash table
 697   or a list and the lookup is made under lock preventing hash table
 698   modifications.
 699 */
 700
 701static __always_inline void sock_hold(struct sock *sk)
 702{
 703	refcount_inc(&sk->sk_refcnt);
 704}
 705
 706/* Ungrab socket in the context, which assumes that socket refcnt
 707   cannot hit zero, f.e. it is true in context of any socketcall.
 708 */
 709static __always_inline void __sock_put(struct sock *sk)
 710{
 711	refcount_dec(&sk->sk_refcnt);
 712}
 713
 714static inline bool sk_del_node_init(struct sock *sk)
 715{
 716	bool rc = __sk_del_node_init(sk);
 717
 718	if (rc) {
 719		/* paranoid for a while -acme */
 720		WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
 721		__sock_put(sk);
 722	}
 723	return rc;
 724}
 725#define sk_del_node_init_rcu(sk)	sk_del_node_init(sk)
 726
 727static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk)
 728{
 729	if (sk_hashed(sk)) {
 730		hlist_nulls_del_init_rcu(&sk->sk_nulls_node);
 731		return true;
 732	}
 733	return false;
 734}
 735
 736static inline bool sk_nulls_del_node_init_rcu(struct sock *sk)
 737{
 738	bool rc = __sk_nulls_del_node_init_rcu(sk);
 739
 740	if (rc) {
 741		/* paranoid for a while -acme */
 742		WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
 743		__sock_put(sk);
 744	}
 745	return rc;
 746}
 747
 748static inline void __sk_add_node(struct sock *sk, struct hlist_head *list)
 749{
 750	hlist_add_head(&sk->sk_node, list);
 751}
 752
 753static inline void sk_add_node(struct sock *sk, struct hlist_head *list)
 754{
 755	sock_hold(sk);
 756	__sk_add_node(sk, list);
 757}
 758
 759static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list)
 760{
 761	sock_hold(sk);
 762	if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport &&
 763	    sk->sk_family == AF_INET6)
 764		hlist_add_tail_rcu(&sk->sk_node, list);
 765	else
 766		hlist_add_head_rcu(&sk->sk_node, list);
 767}
 768
 769static inline void sk_add_node_tail_rcu(struct sock *sk, struct hlist_head *list)
 770{
 771	sock_hold(sk);
 772	hlist_add_tail_rcu(&sk->sk_node, list);
 773}
 774
 775static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
 776{
 777	hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list);
 778}
 779
 780static inline void __sk_nulls_add_node_tail_rcu(struct sock *sk, struct hlist_nulls_head *list)
 781{
 782	hlist_nulls_add_tail_rcu(&sk->sk_nulls_node, list);
 783}
 784
 785static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
 786{
 787	sock_hold(sk);
 788	__sk_nulls_add_node_rcu(sk, list);
 789}
 790
 791static inline void __sk_del_bind_node(struct sock *sk)
 792{
 793	__hlist_del(&sk->sk_bind_node);
 794}
 795
 796static inline void sk_add_bind_node(struct sock *sk,
 797					struct hlist_head *list)
 798{
 799	hlist_add_head(&sk->sk_bind_node, list);
 800}
 801
 802#define sk_for_each(__sk, list) \
 803	hlist_for_each_entry(__sk, list, sk_node)
 804#define sk_for_each_rcu(__sk, list) \
 805	hlist_for_each_entry_rcu(__sk, list, sk_node)
 806#define sk_nulls_for_each(__sk, node, list) \
 807	hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)
 808#define sk_nulls_for_each_rcu(__sk, node, list) \
 809	hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)
 810#define sk_for_each_from(__sk) \
 811	hlist_for_each_entry_from(__sk, sk_node)
 
 812#define sk_nulls_for_each_from(__sk, node) \
 813	if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \
 814		hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node)
 815#define sk_for_each_safe(__sk, tmp, list) \
 816	hlist_for_each_entry_safe(__sk, tmp, list, sk_node)
 817#define sk_for_each_bound(__sk, list) \
 818	hlist_for_each_entry(__sk, list, sk_bind_node)
 819
 820/**
 821 * sk_for_each_entry_offset_rcu - iterate over a list at a given struct offset
 822 * @tpos:	the type * to use as a loop cursor.
 823 * @pos:	the &struct hlist_node to use as a loop cursor.
 824 * @head:	the head for your list.
 825 * @offset:	offset of hlist_node within the struct.
 826 *
 827 */
 828#define sk_for_each_entry_offset_rcu(tpos, pos, head, offset)		       \
 829	for (pos = rcu_dereference(hlist_first_rcu(head));		       \
 830	     pos != NULL &&						       \
 831		({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;});       \
 832	     pos = rcu_dereference(hlist_next_rcu(pos)))
 833
 834static inline struct user_namespace *sk_user_ns(struct sock *sk)
 835{
 836	/* Careful only use this in a context where these parameters
 837	 * can not change and must all be valid, such as recvmsg from
 838	 * userspace.
 839	 */
 840	return sk->sk_socket->file->f_cred->user_ns;
 841}
 842
 843/* Sock flags */
 844enum sock_flags {
 845	SOCK_DEAD,
 846	SOCK_DONE,
 847	SOCK_URGINLINE,
 848	SOCK_KEEPOPEN,
 849	SOCK_LINGER,
 850	SOCK_DESTROY,
 851	SOCK_BROADCAST,
 852	SOCK_TIMESTAMP,
 853	SOCK_ZAPPED,
 854	SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */
 855	SOCK_DBG, /* %SO_DEBUG setting */
 856	SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
 857	SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */
 858	SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
 859	SOCK_MEMALLOC, /* VM depends on this socket for swapping */
 
 
 
 860	SOCK_TIMESTAMPING_RX_SOFTWARE,  /* %SOF_TIMESTAMPING_RX_SOFTWARE */
 
 
 
 861	SOCK_FASYNC, /* fasync() active */
 862	SOCK_RXQ_OVFL,
 863	SOCK_ZEROCOPY, /* buffers from userspace */
 864	SOCK_WIFI_STATUS, /* push wifi status to userspace */
 865	SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS.
 866		     * Will use last 4 bytes of packet sent from
 867		     * user-space instead.
 868		     */
 869	SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */
 870	SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */
 871	SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */
 872	SOCK_TXTIME,
 873	SOCK_XDP, /* XDP is attached */
 874	SOCK_TSTAMP_NEW, /* Indicates 64 bit timestamps always */
 875};
 876
 877#define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))
 878
 879static inline void sock_copy_flags(struct sock *nsk, struct sock *osk)
 880{
 881	nsk->sk_flags = osk->sk_flags;
 882}
 883
 884static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
 885{
 886	__set_bit(flag, &sk->sk_flags);
 887}
 888
 889static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag)
 890{
 891	__clear_bit(flag, &sk->sk_flags);
 892}
 893
 894static inline void sock_valbool_flag(struct sock *sk, enum sock_flags bit,
 895				     int valbool)
 896{
 897	if (valbool)
 898		sock_set_flag(sk, bit);
 899	else
 900		sock_reset_flag(sk, bit);
 901}
 902
 903static inline bool sock_flag(const struct sock *sk, enum sock_flags flag)
 904{
 905	return test_bit(flag, &sk->sk_flags);
 906}
 907
 908#ifdef CONFIG_NET
 909DECLARE_STATIC_KEY_FALSE(memalloc_socks_key);
 910static inline int sk_memalloc_socks(void)
 911{
 912	return static_branch_unlikely(&memalloc_socks_key);
 913}
 914
 915void __receive_sock(struct file *file);
 916#else
 917
 918static inline int sk_memalloc_socks(void)
 919{
 920	return 0;
 921}
 922
 923static inline void __receive_sock(struct file *file)
 924{ }
 925#endif
 926
 927static inline gfp_t sk_gfp_mask(const struct sock *sk, gfp_t gfp_mask)
 928{
 929	return gfp_mask | (sk->sk_allocation & __GFP_MEMALLOC);
 930}
 931
 932static inline void sk_acceptq_removed(struct sock *sk)
 933{
 934	WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog - 1);
 935}
 936
 937static inline void sk_acceptq_added(struct sock *sk)
 938{
 939	WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog + 1);
 940}
 941
 942/* Note: If you think the test should be:
 943 *	return READ_ONCE(sk->sk_ack_backlog) >= READ_ONCE(sk->sk_max_ack_backlog);
 944 * Then please take a look at commit 64a146513f8f ("[NET]: Revert incorrect accept queue backlog changes.")
 945 */
 946static inline bool sk_acceptq_is_full(const struct sock *sk)
 947{
 948	return READ_ONCE(sk->sk_ack_backlog) > READ_ONCE(sk->sk_max_ack_backlog);
 949}
 950
 951/*
 952 * Compute minimal free write space needed to queue new packets.
 953 */
 954static inline int sk_stream_min_wspace(const struct sock *sk)
 955{
 956	return READ_ONCE(sk->sk_wmem_queued) >> 1;
 957}
 958
 959static inline int sk_stream_wspace(const struct sock *sk)
 960{
 961	return READ_ONCE(sk->sk_sndbuf) - READ_ONCE(sk->sk_wmem_queued);
 962}
 963
 964static inline void sk_wmem_queued_add(struct sock *sk, int val)
 
 
 965{
 966	WRITE_ONCE(sk->sk_wmem_queued, sk->sk_wmem_queued + val);
 967}
 968
 969void sk_stream_write_space(struct sock *sk);
 970
 971/* OOB backlog add */
 972static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
 973{
 974	/* dont let skb dst not refcounted, we are going to leave rcu lock */
 975	skb_dst_force(skb);
 976
 977	if (!sk->sk_backlog.tail)
 978		WRITE_ONCE(sk->sk_backlog.head, skb);
 979	else
 980		sk->sk_backlog.tail->next = skb;
 981
 982	WRITE_ONCE(sk->sk_backlog.tail, skb);
 983	skb->next = NULL;
 984}
 985
 986/*
 987 * Take into account size of receive queue and backlog queue
 988 * Do not take into account this skb truesize,
 989 * to allow even a single big packet to come.
 990 */
 991static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit)
 
 992{
 993	unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc);
 994
 995	return qsize > limit;
 996}
 997
 998/* The per-socket spinlock must be held here. */
 999static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb,
1000					      unsigned int limit)
1001{
1002	if (sk_rcvqueues_full(sk, limit))
1003		return -ENOBUFS;
1004
1005	/*
1006	 * If the skb was allocated from pfmemalloc reserves, only
1007	 * allow SOCK_MEMALLOC sockets to use it as this socket is
1008	 * helping free memory
1009	 */
1010	if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC))
1011		return -ENOMEM;
1012
1013	__sk_add_backlog(sk, skb);
1014	sk->sk_backlog.len += skb->truesize;
1015	return 0;
1016}
1017
1018int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb);
1019
1020static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
1021{
1022	if (sk_memalloc_socks() && skb_pfmemalloc(skb))
1023		return __sk_backlog_rcv(sk, skb);
1024
1025	return sk->sk_backlog_rcv(sk, skb);
1026}
1027
1028static inline void sk_incoming_cpu_update(struct sock *sk)
1029{
1030	int cpu = raw_smp_processor_id();
1031
1032	if (unlikely(READ_ONCE(sk->sk_incoming_cpu) != cpu))
1033		WRITE_ONCE(sk->sk_incoming_cpu, cpu);
1034}
1035
1036static inline void sock_rps_record_flow_hash(__u32 hash)
1037{
1038#ifdef CONFIG_RPS
1039	struct rps_sock_flow_table *sock_flow_table;
1040
1041	rcu_read_lock();
1042	sock_flow_table = rcu_dereference(rps_sock_flow_table);
1043	rps_record_sock_flow(sock_flow_table, hash);
1044	rcu_read_unlock();
1045#endif
1046}
1047
1048static inline void sock_rps_record_flow(const struct sock *sk)
1049{
1050#ifdef CONFIG_RPS
1051	if (static_branch_unlikely(&rfs_needed)) {
1052		/* Reading sk->sk_rxhash might incur an expensive cache line
1053		 * miss.
1054		 *
1055		 * TCP_ESTABLISHED does cover almost all states where RFS
1056		 * might be useful, and is cheaper [1] than testing :
1057		 *	IPv4: inet_sk(sk)->inet_daddr
1058		 * 	IPv6: ipv6_addr_any(&sk->sk_v6_daddr)
1059		 * OR	an additional socket flag
1060		 * [1] : sk_state and sk_prot are in the same cache line.
1061		 */
1062		if (sk->sk_state == TCP_ESTABLISHED)
1063			sock_rps_record_flow_hash(sk->sk_rxhash);
1064	}
1065#endif
1066}
1067
1068static inline void sock_rps_save_rxhash(struct sock *sk,
1069					const struct sk_buff *skb)
1070{
1071#ifdef CONFIG_RPS
1072	if (unlikely(sk->sk_rxhash != skb->hash))
1073		sk->sk_rxhash = skb->hash;
 
 
1074#endif
1075}
1076
1077static inline void sock_rps_reset_rxhash(struct sock *sk)
1078{
1079#ifdef CONFIG_RPS
 
1080	sk->sk_rxhash = 0;
1081#endif
1082}
1083
1084#define sk_wait_event(__sk, __timeo, __condition, __wait)		\
1085	({	int __rc;						\
1086		release_sock(__sk);					\
1087		__rc = __condition;					\
1088		if (!__rc) {						\
1089			*(__timeo) = wait_woken(__wait,			\
1090						TASK_INTERRUPTIBLE,	\
1091						*(__timeo));		\
1092		}							\
1093		sched_annotate_sleep();					\
1094		lock_sock(__sk);					\
1095		__rc = __condition;					\
1096		__rc;							\
1097	})
1098
1099int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
1100int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
1101void sk_stream_wait_close(struct sock *sk, long timeo_p);
1102int sk_stream_error(struct sock *sk, int flags, int err);
1103void sk_stream_kill_queues(struct sock *sk);
1104void sk_set_memalloc(struct sock *sk);
1105void sk_clear_memalloc(struct sock *sk);
1106
1107void __sk_flush_backlog(struct sock *sk);
1108
1109static inline bool sk_flush_backlog(struct sock *sk)
1110{
1111	if (unlikely(READ_ONCE(sk->sk_backlog.tail))) {
1112		__sk_flush_backlog(sk);
1113		return true;
1114	}
1115	return false;
1116}
1117
1118int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb);
1119
1120struct request_sock_ops;
1121struct timewait_sock_ops;
1122struct inet_hashinfo;
1123struct raw_hashinfo;
1124struct smc_hashinfo;
1125struct module;
1126struct sk_psock;
1127
1128/*
1129 * caches using SLAB_TYPESAFE_BY_RCU should let .next pointer from nulls nodes
1130 * un-modified. Special care is taken when initializing object to zero.
1131 */
1132static inline void sk_prot_clear_nulls(struct sock *sk, int size)
1133{
1134	if (offsetof(struct sock, sk_node.next) != 0)
1135		memset(sk, 0, offsetof(struct sock, sk_node.next));
1136	memset(&sk->sk_node.pprev, 0,
1137	       size - offsetof(struct sock, sk_node.pprev));
1138}
1139
1140/* Networking protocol blocks we attach to sockets.
1141 * socket layer -> transport layer interface
 
1142 */
1143struct proto {
1144	void			(*close)(struct sock *sk,
1145					long timeout);
1146	int			(*pre_connect)(struct sock *sk,
1147					struct sockaddr *uaddr,
1148					int addr_len);
1149	int			(*connect)(struct sock *sk,
1150					struct sockaddr *uaddr,
1151					int addr_len);
1152	int			(*disconnect)(struct sock *sk, int flags);
1153
1154	struct sock *		(*accept)(struct sock *sk, int flags, int *err,
1155					  bool kern);
1156
1157	int			(*ioctl)(struct sock *sk, int cmd,
1158					 unsigned long arg);
1159	int			(*init)(struct sock *sk);
1160	void			(*destroy)(struct sock *sk);
1161	void			(*shutdown)(struct sock *sk, int how);
1162	int			(*setsockopt)(struct sock *sk, int level,
1163					int optname, sockptr_t optval,
1164					unsigned int optlen);
1165	int			(*getsockopt)(struct sock *sk, int level,
1166					int optname, char __user *optval,
1167					int __user *option);
1168	void			(*keepalive)(struct sock *sk, int valbool);
1169#ifdef CONFIG_COMPAT
 
 
 
 
 
 
 
 
1170	int			(*compat_ioctl)(struct sock *sk,
1171					unsigned int cmd, unsigned long arg);
1172#endif
1173	int			(*sendmsg)(struct sock *sk, struct msghdr *msg,
1174					   size_t len);
1175	int			(*recvmsg)(struct sock *sk, struct msghdr *msg,
 
1176					   size_t len, int noblock, int flags,
1177					   int *addr_len);
1178	int			(*sendpage)(struct sock *sk, struct page *page,
1179					int offset, size_t size, int flags);
1180	int			(*bind)(struct sock *sk,
1181					struct sockaddr *addr, int addr_len);
1182	int			(*bind_add)(struct sock *sk,
1183					struct sockaddr *addr, int addr_len);
1184
1185	int			(*backlog_rcv) (struct sock *sk,
1186						struct sk_buff *skb);
1187	bool			(*bpf_bypass_getsockopt)(int level,
1188							 int optname);
1189
1190	void		(*release_cb)(struct sock *sk);
1191
1192	/* Keeping track of sk's, looking them up, and port selection methods. */
1193	int			(*hash)(struct sock *sk);
1194	void			(*unhash)(struct sock *sk);
1195	void			(*rehash)(struct sock *sk);
1196	int			(*get_port)(struct sock *sk, unsigned short snum);
1197#ifdef CONFIG_BPF_SYSCALL
1198	int			(*psock_update_sk_prot)(struct sock *sk,
1199							struct sk_psock *psock,
1200							bool restore);
1201#endif
1202
1203	/* Keeping track of sockets in use */
1204#ifdef CONFIG_PROC_FS
1205	unsigned int		inuse_idx;
1206#endif
1207
1208	bool			(*stream_memory_free)(const struct sock *sk, int wake);
1209	bool			(*stream_memory_read)(const struct sock *sk);
1210	/* Memory pressure */
1211	void			(*enter_memory_pressure)(struct sock *sk);
1212	void			(*leave_memory_pressure)(struct sock *sk);
1213	atomic_long_t		*memory_allocated;	/* Current allocated memory. */
1214	struct percpu_counter	*sockets_allocated;	/* Current number of sockets. */
1215	/*
1216	 * Pressure flag: try to collapse.
1217	 * Technical note: it is used by multiple contexts non atomically.
1218	 * All the __sk_mem_schedule() is of this nature: accounting
1219	 * is strict, actions are advisory and have some latency.
1220	 */
1221	unsigned long		*memory_pressure;
1222	long			*sysctl_mem;
1223
1224	int			*sysctl_wmem;
1225	int			*sysctl_rmem;
1226	u32			sysctl_wmem_offset;
1227	u32			sysctl_rmem_offset;
1228
1229	int			max_header;
1230	bool			no_autobind;
1231
1232	struct kmem_cache	*slab;
1233	unsigned int		obj_size;
1234	slab_flags_t		slab_flags;
1235	unsigned int		useroffset;	/* Usercopy region offset */
1236	unsigned int		usersize;	/* Usercopy region size */
1237
1238	struct percpu_counter	*orphan_count;
1239
1240	struct request_sock_ops	*rsk_prot;
1241	struct timewait_sock_ops *twsk_prot;
1242
1243	union {
1244		struct inet_hashinfo	*hashinfo;
1245		struct udp_table	*udp_table;
1246		struct raw_hashinfo	*raw_hash;
1247		struct smc_hashinfo	*smc_hash;
1248	} h;
1249
1250	struct module		*owner;
1251
1252	char			name[32];
1253
1254	struct list_head	node;
1255#ifdef SOCK_REFCNT_DEBUG
1256	atomic_t		socks;
1257#endif
1258	int			(*diag_destroy)(struct sock *sk, int err);
1259} __randomize_layout;
 
 
 
 
 
 
 
 
 
 
 
1260
1261int proto_register(struct proto *prot, int alloc_slab);
1262void proto_unregister(struct proto *prot);
1263int sock_load_diag_module(int family, int protocol);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1264
1265#ifdef SOCK_REFCNT_DEBUG
1266static inline void sk_refcnt_debug_inc(struct sock *sk)
1267{
1268	atomic_inc(&sk->sk_prot->socks);
1269}
1270
1271static inline void sk_refcnt_debug_dec(struct sock *sk)
1272{
1273	atomic_dec(&sk->sk_prot->socks);
1274	printk(KERN_DEBUG "%s socket %p released, %d are still alive\n",
1275	       sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks));
1276}
1277
1278static inline void sk_refcnt_debug_release(const struct sock *sk)
1279{
1280	if (refcount_read(&sk->sk_refcnt) != 1)
1281		printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n",
1282		       sk->sk_prot->name, sk, refcount_read(&sk->sk_refcnt));
1283}
1284#else /* SOCK_REFCNT_DEBUG */
1285#define sk_refcnt_debug_inc(sk) do { } while (0)
1286#define sk_refcnt_debug_dec(sk) do { } while (0)
1287#define sk_refcnt_debug_release(sk) do { } while (0)
1288#endif /* SOCK_REFCNT_DEBUG */
1289
1290INDIRECT_CALLABLE_DECLARE(bool tcp_stream_memory_free(const struct sock *sk, int wake));
1291
1292static inline bool __sk_stream_memory_free(const struct sock *sk, int wake)
 
1293{
1294	if (READ_ONCE(sk->sk_wmem_queued) >= READ_ONCE(sk->sk_sndbuf))
1295		return false;
1296
1297#ifdef CONFIG_INET
1298	return sk->sk_prot->stream_memory_free ?
1299		INDIRECT_CALL_1(sk->sk_prot->stream_memory_free,
1300			        tcp_stream_memory_free,
1301				sk, wake) : true;
1302#else
1303	return sk->sk_prot->stream_memory_free ?
1304		sk->sk_prot->stream_memory_free(sk, wake) : true;
1305#endif
 
 
1306}
 
1307
1308static inline bool sk_stream_memory_free(const struct sock *sk)
 
1309{
1310	return __sk_stream_memory_free(sk, 0);
1311}
1312
1313static inline bool __sk_stream_is_writeable(const struct sock *sk, int wake)
1314{
1315	return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) &&
1316	       __sk_stream_memory_free(sk, wake);
 
 
 
 
 
1317}
1318
1319static inline bool sk_stream_is_writeable(const struct sock *sk)
1320{
1321	return __sk_stream_is_writeable(sk, 0);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1322}
1323
1324static inline int sk_under_cgroup_hierarchy(struct sock *sk,
1325					    struct cgroup *ancestor)
1326{
1327#ifdef CONFIG_SOCK_CGROUP_DATA
1328	return cgroup_is_descendant(sock_cgroup_ptr(&sk->sk_cgrp_data),
1329				    ancestor);
1330#else
1331	return -ENOTSUPP;
1332#endif
 
 
 
 
 
 
1333}
1334
1335static inline bool sk_has_memory_pressure(const struct sock *sk)
1336{
1337	return sk->sk_prot->memory_pressure != NULL;
 
 
 
1338}
1339
1340static inline bool sk_under_memory_pressure(const struct sock *sk)
 
 
1341{
1342	if (!sk->sk_prot->memory_pressure)
1343		return false;
1344
1345	if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
1346	    mem_cgroup_under_socket_pressure(sk->sk_memcg))
1347		return true;
 
 
1348
1349	return !!*sk->sk_prot->memory_pressure;
 
 
 
 
 
 
 
 
 
 
1350}
1351
1352static inline long
1353sk_memory_allocated(const struct sock *sk)
1354{
1355	return atomic_long_read(sk->sk_prot->memory_allocated);
 
 
 
 
1356}
1357
1358static inline long
1359sk_memory_allocated_add(struct sock *sk, int amt)
1360{
1361	return atomic_long_add_return(amt, sk->sk_prot->memory_allocated);
 
 
 
 
 
 
 
 
 
1362}
1363
1364static inline void
1365sk_memory_allocated_sub(struct sock *sk, int amt)
1366{
1367	atomic_long_sub(amt, sk->sk_prot->memory_allocated);
1368}
 
 
1369
1370#define SK_ALLOC_PERCPU_COUNTER_BATCH 16
 
1371
1372static inline void sk_sockets_allocated_dec(struct sock *sk)
1373{
1374	percpu_counter_add_batch(sk->sk_prot->sockets_allocated, -1,
1375				 SK_ALLOC_PERCPU_COUNTER_BATCH);
 
 
 
 
 
 
 
 
1376}
1377
1378static inline void sk_sockets_allocated_inc(struct sock *sk)
1379{
1380	percpu_counter_add_batch(sk->sk_prot->sockets_allocated, 1,
1381				 SK_ALLOC_PERCPU_COUNTER_BATCH);
 
 
 
 
 
 
 
 
1382}
1383
1384static inline u64
1385sk_sockets_allocated_read_positive(struct sock *sk)
1386{
1387	return percpu_counter_read_positive(sk->sk_prot->sockets_allocated);
 
 
 
 
 
1388}
1389
1390static inline int
1391proto_sockets_allocated_sum_positive(struct proto *prot)
1392{
1393	return percpu_counter_sum_positive(prot->sockets_allocated);
1394}
1395
1396static inline long
1397proto_memory_allocated(struct proto *prot)
1398{
1399	return atomic_long_read(prot->memory_allocated);
1400}
1401
1402static inline bool
1403proto_memory_pressure(struct proto *prot)
1404{
1405	if (!prot->memory_pressure)
1406		return false;
1407	return !!*prot->memory_pressure;
1408}
1409
1410
1411#ifdef CONFIG_PROC_FS
1412/* Called with local bh disabled */
1413void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc);
1414int sock_prot_inuse_get(struct net *net, struct proto *proto);
1415int sock_inuse_get(struct net *net);
1416#else
1417static inline void sock_prot_inuse_add(struct net *net, struct proto *prot,
1418		int inc)
1419{
1420}
1421#endif
1422
1423
1424/* With per-bucket locks this operation is not-atomic, so that
1425 * this version is not worse.
1426 */
1427static inline int __sk_prot_rehash(struct sock *sk)
1428{
1429	sk->sk_prot->unhash(sk);
1430	return sk->sk_prot->hash(sk);
1431}
1432
 
 
1433/* About 10 seconds */
1434#define SOCK_DESTROY_TIME (10*HZ)
1435
1436/* Sockets 0-1023 can't be bound to unless you are superuser */
1437#define PROT_SOCK	1024
1438
1439#define SHUTDOWN_MASK	3
1440#define RCV_SHUTDOWN	1
1441#define SEND_SHUTDOWN	2
1442
1443#define SOCK_SNDBUF_LOCK	1
1444#define SOCK_RCVBUF_LOCK	2
1445#define SOCK_BINDADDR_LOCK	4
1446#define SOCK_BINDPORT_LOCK	8
1447
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1448struct socket_alloc {
1449	struct socket socket;
1450	struct inode vfs_inode;
1451};
1452
1453static inline struct socket *SOCKET_I(struct inode *inode)
1454{
1455	return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
1456}
1457
1458static inline struct inode *SOCK_INODE(struct socket *socket)
1459{
1460	return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
1461}
1462
1463/*
1464 * Functions for memory accounting
1465 */
1466int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind);
1467int __sk_mem_schedule(struct sock *sk, int size, int kind);
1468void __sk_mem_reduce_allocated(struct sock *sk, int amount);
1469void __sk_mem_reclaim(struct sock *sk, int amount);
1470
1471/* We used to have PAGE_SIZE here, but systems with 64KB pages
1472 * do not necessarily have 16x time more memory than 4KB ones.
1473 */
1474#define SK_MEM_QUANTUM 4096
1475#define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM)
1476#define SK_MEM_SEND	0
1477#define SK_MEM_RECV	1
1478
1479/* sysctl_mem values are in pages, we convert them in SK_MEM_QUANTUM units */
1480static inline long sk_prot_mem_limits(const struct sock *sk, int index)
1481{
1482	long val = sk->sk_prot->sysctl_mem[index];
1483
1484#if PAGE_SIZE > SK_MEM_QUANTUM
1485	val <<= PAGE_SHIFT - SK_MEM_QUANTUM_SHIFT;
1486#elif PAGE_SIZE < SK_MEM_QUANTUM
1487	val >>= SK_MEM_QUANTUM_SHIFT - PAGE_SHIFT;
1488#endif
1489	return val;
1490}
1491
1492static inline int sk_mem_pages(int amt)
1493{
1494	return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT;
1495}
1496
1497static inline bool sk_has_account(struct sock *sk)
1498{
1499	/* return true if protocol supports memory accounting */
1500	return !!sk->sk_prot->memory_allocated;
1501}
1502
1503static inline bool sk_wmem_schedule(struct sock *sk, int size)
1504{
1505	if (!sk_has_account(sk))
1506		return true;
1507	return size <= sk->sk_forward_alloc ||
1508		__sk_mem_schedule(sk, size, SK_MEM_SEND);
1509}
1510
1511static inline bool
1512sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size)
1513{
1514	if (!sk_has_account(sk))
1515		return true;
1516	return size <= sk->sk_forward_alloc ||
1517		__sk_mem_schedule(sk, size, SK_MEM_RECV) ||
1518		skb_pfmemalloc(skb);
1519}
1520
1521static inline void sk_mem_reclaim(struct sock *sk)
1522{
1523	if (!sk_has_account(sk))
1524		return;
1525	if (sk->sk_forward_alloc >= SK_MEM_QUANTUM)
1526		__sk_mem_reclaim(sk, sk->sk_forward_alloc);
1527}
1528
1529static inline void sk_mem_reclaim_partial(struct sock *sk)
1530{
1531	if (!sk_has_account(sk))
1532		return;
1533	if (sk->sk_forward_alloc > SK_MEM_QUANTUM)
1534		__sk_mem_reclaim(sk, sk->sk_forward_alloc - 1);
1535}
1536
1537static inline void sk_mem_charge(struct sock *sk, int size)
1538{
1539	if (!sk_has_account(sk))
1540		return;
1541	sk->sk_forward_alloc -= size;
1542}
1543
1544static inline void sk_mem_uncharge(struct sock *sk, int size)
1545{
1546	if (!sk_has_account(sk))
1547		return;
1548	sk->sk_forward_alloc += size;
1549
1550	/* Avoid a possible overflow.
1551	 * TCP send queues can make this happen, if sk_mem_reclaim()
1552	 * is not called and more than 2 GBytes are released at once.
1553	 *
1554	 * If we reach 2 MBytes, reclaim 1 MBytes right now, there is
1555	 * no need to hold that much forward allocation anyway.
1556	 */
1557	if (unlikely(sk->sk_forward_alloc >= 1 << 21))
1558		__sk_mem_reclaim(sk, 1 << 20);
1559}
1560
1561DECLARE_STATIC_KEY_FALSE(tcp_tx_skb_cache_key);
1562static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb)
1563{
1564	sk_wmem_queued_add(sk, -skb->truesize);
 
1565	sk_mem_uncharge(sk, skb->truesize);
1566	if (static_branch_unlikely(&tcp_tx_skb_cache_key) &&
1567	    !sk->sk_tx_skb_cache && !skb_cloned(skb)) {
1568		skb_ext_reset(skb);
1569		skb_zcopy_clear(skb, true);
1570		sk->sk_tx_skb_cache = skb;
1571		return;
1572	}
1573	__kfree_skb(skb);
1574}
1575
1576static inline void sock_release_ownership(struct sock *sk)
1577{
1578	if (sk->sk_lock.owned) {
1579		sk->sk_lock.owned = 0;
1580
1581		/* The sk_lock has mutex_unlock() semantics: */
1582		mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
1583	}
1584}
 
 
 
 
 
1585
1586/*
1587 * Macro so as to not evaluate some arguments when
1588 * lockdep is not enabled.
1589 *
1590 * Mark both the sk_lock and the sk_lock.slock as a
1591 * per-address-family lock class.
1592 */
1593#define sock_lock_init_class_and_name(sk, sname, skey, name, key)	\
1594do {									\
1595	sk->sk_lock.owned = 0;						\
1596	init_waitqueue_head(&sk->sk_lock.wq);				\
1597	spin_lock_init(&(sk)->sk_lock.slock);				\
1598	debug_check_no_locks_freed((void *)&(sk)->sk_lock,		\
1599			sizeof((sk)->sk_lock));				\
1600	lockdep_set_class_and_name(&(sk)->sk_lock.slock,		\
1601				(skey), (sname));				\
1602	lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0);	\
1603} while (0)
1604
1605static inline bool lockdep_sock_is_held(const struct sock *sk)
1606{
1607	return lockdep_is_held(&sk->sk_lock) ||
1608	       lockdep_is_held(&sk->sk_lock.slock);
1609}
1610
1611void lock_sock_nested(struct sock *sk, int subclass);
1612
1613static inline void lock_sock(struct sock *sk)
1614{
1615	lock_sock_nested(sk, 0);
1616}
1617
1618void __lock_sock(struct sock *sk);
1619void __release_sock(struct sock *sk);
1620void release_sock(struct sock *sk);
1621
1622/* BH context may only use the following locking interface. */
1623#define bh_lock_sock(__sk)	spin_lock(&((__sk)->sk_lock.slock))
1624#define bh_lock_sock_nested(__sk) \
1625				spin_lock_nested(&((__sk)->sk_lock.slock), \
1626				SINGLE_DEPTH_NESTING)
1627#define bh_unlock_sock(__sk)	spin_unlock(&((__sk)->sk_lock.slock))
1628
1629bool lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock);
1630
1631/**
1632 * unlock_sock_fast - complement of lock_sock_fast
1633 * @sk: socket
1634 * @slow: slow mode
1635 *
1636 * fast unlock socket for user context.
1637 * If slow mode is on, we call regular release_sock()
1638 */
1639static inline void unlock_sock_fast(struct sock *sk, bool slow)
1640	__releases(&sk->sk_lock.slock)
1641{
1642	if (slow) {
1643		release_sock(sk);
1644		__release(&sk->sk_lock.slock);
1645	} else {
1646		spin_unlock_bh(&sk->sk_lock.slock);
1647	}
1648}
1649
1650/* Used by processes to "lock" a socket state, so that
1651 * interrupts and bottom half handlers won't change it
1652 * from under us. It essentially blocks any incoming
1653 * packets, so that we won't get any new data or any
1654 * packets that change the state of the socket.
1655 *
1656 * While locked, BH processing will add new packets to
1657 * the backlog queue.  This queue is processed by the
1658 * owner of the socket lock right before it is released.
1659 *
1660 * Since ~2.3.5 it is also exclusive sleep lock serializing
1661 * accesses from user process context.
1662 */
1663
1664static inline void sock_owned_by_me(const struct sock *sk)
1665{
1666#ifdef CONFIG_LOCKDEP
1667	WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks);
1668#endif
1669}
1670
1671static inline bool sock_owned_by_user(const struct sock *sk)
1672{
1673	sock_owned_by_me(sk);
1674	return sk->sk_lock.owned;
1675}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1676
1677static inline bool sock_owned_by_user_nocheck(const struct sock *sk)
1678{
1679	return sk->sk_lock.owned;
1680}
1681
1682/* no reclassification while locks are held */
1683static inline bool sock_allow_reclassification(const struct sock *csk)
1684{
1685	struct sock *sk = (struct sock *)csk;
1686
1687	return !sk->sk_lock.owned && !spin_is_locked(&sk->sk_lock.slock);
1688}
1689
1690struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1691		      struct proto *prot, int kern);
1692void sk_free(struct sock *sk);
1693void sk_destruct(struct sock *sk);
1694struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority);
1695void sk_free_unlock_clone(struct sock *sk);
1696
1697struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1698			     gfp_t priority);
1699void __sock_wfree(struct sk_buff *skb);
1700void sock_wfree(struct sk_buff *skb);
1701struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
1702			     gfp_t priority);
1703void skb_orphan_partial(struct sk_buff *skb);
1704void sock_rfree(struct sk_buff *skb);
1705void sock_efree(struct sk_buff *skb);
1706#ifdef CONFIG_INET
1707void sock_edemux(struct sk_buff *skb);
1708void sock_pfree(struct sk_buff *skb);
1709#else
1710#define sock_edemux sock_efree
1711#endif
1712
1713int sock_setsockopt(struct socket *sock, int level, int op,
1714		    sockptr_t optval, unsigned int optlen);
1715
1716int sock_getsockopt(struct socket *sock, int level, int op,
1717		    char __user *optval, int __user *optlen);
1718int sock_gettstamp(struct socket *sock, void __user *userstamp,
1719		   bool timeval, bool time32);
1720struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1721				    int noblock, int *errcode);
1722struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1723				     unsigned long data_len, int noblock,
1724				     int *errcode, int max_page_order);
1725void *sock_kmalloc(struct sock *sk, int size, gfp_t priority);
1726void sock_kfree_s(struct sock *sk, void *mem, int size);
1727void sock_kzfree_s(struct sock *sk, void *mem, int size);
1728void sk_send_sigurg(struct sock *sk);
1729
1730struct sockcm_cookie {
1731	u64 transmit_time;
1732	u32 mark;
1733	u16 tsflags;
1734};
1735
1736static inline void sockcm_init(struct sockcm_cookie *sockc,
1737			       const struct sock *sk)
1738{
1739	*sockc = (struct sockcm_cookie) { .tsflags = sk->sk_tsflags };
1740}
1741
1742int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg,
1743		     struct sockcm_cookie *sockc);
1744int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
1745		   struct sockcm_cookie *sockc);
1746
1747/*
1748 * Functions to fill in entries in struct proto_ops when a protocol
1749 * does not implement a particular function.
1750 */
1751int sock_no_bind(struct socket *, struct sockaddr *, int);
1752int sock_no_connect(struct socket *, struct sockaddr *, int, int);
1753int sock_no_socketpair(struct socket *, struct socket *);
1754int sock_no_accept(struct socket *, struct socket *, int, bool);
1755int sock_no_getname(struct socket *, struct sockaddr *, int);
1756int sock_no_ioctl(struct socket *, unsigned int, unsigned long);
1757int sock_no_listen(struct socket *, int);
1758int sock_no_shutdown(struct socket *, int);
1759int sock_no_sendmsg(struct socket *, struct msghdr *, size_t);
1760int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len);
1761int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int);
1762int sock_no_mmap(struct file *file, struct socket *sock,
1763		 struct vm_area_struct *vma);
1764ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset,
1765			 size_t size, int flags);
1766ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
1767				int offset, size_t size, int flags);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1768
1769/*
1770 * Functions to fill in entries in struct proto_ops when a protocol
1771 * uses the inet style.
1772 */
1773int sock_common_getsockopt(struct socket *sock, int level, int optname,
1774				  char __user *optval, int __user *optlen);
1775int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1776			int flags);
1777int sock_common_setsockopt(struct socket *sock, int level, int optname,
1778			   sockptr_t optval, unsigned int optlen);
 
 
 
 
1779
1780void sk_common_release(struct sock *sk);
1781
1782/*
1783 *	Default socket callbacks and setup code
1784 */
1785
1786/* Initialise core socket variables */
1787void sock_init_data(struct socket *sock, struct sock *sk);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1788
1789/*
1790 * Socket reference counting postulates.
1791 *
1792 * * Each user of socket SHOULD hold a reference count.
1793 * * Each access point to socket (an hash table bucket, reference from a list,
1794 *   running timer, skb in flight MUST hold a reference count.
1795 * * When reference count hits 0, it means it will never increase back.
1796 * * When reference count hits 0, it means that no references from
1797 *   outside exist to this socket and current process on current CPU
1798 *   is last user and may/should destroy this socket.
1799 * * sk_free is called from any context: process, BH, IRQ. When
1800 *   it is called, socket has no references from outside -> sk_free
1801 *   may release descendant resources allocated by the socket, but
1802 *   to the time when it is called, socket is NOT referenced by any
1803 *   hash tables, lists etc.
1804 * * Packets, delivered from outside (from network or from another process)
1805 *   and enqueued on receive/error queues SHOULD NOT grab reference count,
1806 *   when they sit in queue. Otherwise, packets will leak to hole, when
1807 *   socket is looked up by one cpu and unhasing is made by another CPU.
1808 *   It is true for udp/raw, netlink (leak to receive and error queues), tcp
1809 *   (leak to backlog). Packet socket does all the processing inside
1810 *   BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
1811 *   use separate SMP lock, so that they are prone too.
1812 */
1813
1814/* Ungrab socket and destroy it, if it was the last reference. */
1815static inline void sock_put(struct sock *sk)
1816{
1817	if (refcount_dec_and_test(&sk->sk_refcnt))
1818		sk_free(sk);
1819}
1820/* Generic version of sock_put(), dealing with all sockets
1821 * (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...)
1822 */
1823void sock_gen_put(struct sock *sk);
1824
1825int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested,
1826		     unsigned int trim_cap, bool refcounted);
1827static inline int sk_receive_skb(struct sock *sk, struct sk_buff *skb,
1828				 const int nested)
1829{
1830	return __sk_receive_skb(sk, skb, nested, 1, true);
1831}
1832
1833static inline void sk_tx_queue_set(struct sock *sk, int tx_queue)
1834{
1835	/* sk_tx_queue_mapping accept only upto a 16-bit value */
1836	if (WARN_ON_ONCE((unsigned short)tx_queue >= USHRT_MAX))
1837		return;
1838	sk->sk_tx_queue_mapping = tx_queue;
1839}
1840
1841#define NO_QUEUE_MAPPING	USHRT_MAX
1842
1843static inline void sk_tx_queue_clear(struct sock *sk)
1844{
1845	sk->sk_tx_queue_mapping = NO_QUEUE_MAPPING;
1846}
1847
1848static inline int sk_tx_queue_get(const struct sock *sk)
1849{
1850	if (sk && sk->sk_tx_queue_mapping != NO_QUEUE_MAPPING)
1851		return sk->sk_tx_queue_mapping;
1852
1853	return -1;
1854}
1855
1856static inline void sk_rx_queue_set(struct sock *sk, const struct sk_buff *skb)
1857{
1858#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
1859	if (skb_rx_queue_recorded(skb)) {
1860		u16 rx_queue = skb_get_rx_queue(skb);
1861
1862		if (WARN_ON_ONCE(rx_queue == NO_QUEUE_MAPPING))
1863			return;
1864
1865		sk->sk_rx_queue_mapping = rx_queue;
1866	}
1867#endif
1868}
1869
1870static inline void sk_rx_queue_clear(struct sock *sk)
1871{
1872#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
1873	sk->sk_rx_queue_mapping = NO_QUEUE_MAPPING;
1874#endif
1875}
1876
1877static inline int sk_rx_queue_get(const struct sock *sk)
1878{
1879#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
1880	if (sk && sk->sk_rx_queue_mapping != NO_QUEUE_MAPPING)
1881		return sk->sk_rx_queue_mapping;
1882#endif
1883
1884	return -1;
1885}
1886
1887static inline void sk_set_socket(struct sock *sk, struct socket *sock)
1888{
 
1889	sk->sk_socket = sock;
1890}
1891
1892static inline wait_queue_head_t *sk_sleep(struct sock *sk)
1893{
1894	BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0);
1895	return &rcu_dereference_raw(sk->sk_wq)->wait;
1896}
1897/* Detach socket from process context.
1898 * Announce socket dead, detach it from wait queue and inode.
1899 * Note that parent inode held reference count on this struct sock,
1900 * we do not release it in this function, because protocol
1901 * probably wants some additional cleanups or even continuing
1902 * to work with this socket (TCP).
1903 */
1904static inline void sock_orphan(struct sock *sk)
1905{
1906	write_lock_bh(&sk->sk_callback_lock);
1907	sock_set_flag(sk, SOCK_DEAD);
1908	sk_set_socket(sk, NULL);
1909	sk->sk_wq  = NULL;
1910	write_unlock_bh(&sk->sk_callback_lock);
1911}
1912
1913static inline void sock_graft(struct sock *sk, struct socket *parent)
1914{
1915	WARN_ON(parent->sk);
1916	write_lock_bh(&sk->sk_callback_lock);
1917	rcu_assign_pointer(sk->sk_wq, &parent->wq);
1918	parent->sk = sk;
1919	sk_set_socket(sk, parent);
1920	sk->sk_uid = SOCK_INODE(parent)->i_uid;
1921	security_sock_graft(sk, parent);
1922	write_unlock_bh(&sk->sk_callback_lock);
1923}
1924
1925kuid_t sock_i_uid(struct sock *sk);
1926unsigned long sock_i_ino(struct sock *sk);
1927
1928static inline kuid_t sock_net_uid(const struct net *net, const struct sock *sk)
1929{
1930	return sk ? sk->sk_uid : make_kuid(net->user_ns, 0);
1931}
1932
1933static inline u32 net_tx_rndhash(void)
1934{
1935	u32 v = prandom_u32();
1936
1937	return v ?: 1;
1938}
1939
1940static inline void sk_set_txhash(struct sock *sk)
1941{
1942	/* This pairs with READ_ONCE() in skb_set_hash_from_sk() */
1943	WRITE_ONCE(sk->sk_txhash, net_tx_rndhash());
1944}
1945
1946static inline bool sk_rethink_txhash(struct sock *sk)
1947{
1948	if (sk->sk_txhash) {
1949		sk_set_txhash(sk);
1950		return true;
1951	}
1952	return false;
1953}
1954
1955static inline struct dst_entry *
1956__sk_dst_get(struct sock *sk)
1957{
1958	return rcu_dereference_check(sk->sk_dst_cache,
1959				     lockdep_sock_is_held(sk));
1960}
1961
1962static inline struct dst_entry *
1963sk_dst_get(struct sock *sk)
1964{
1965	struct dst_entry *dst;
1966
1967	rcu_read_lock();
1968	dst = rcu_dereference(sk->sk_dst_cache);
1969	if (dst && !atomic_inc_not_zero(&dst->__refcnt))
1970		dst = NULL;
1971	rcu_read_unlock();
1972	return dst;
1973}
1974
1975static inline void __dst_negative_advice(struct sock *sk)
 
 
1976{
1977	struct dst_entry *ndst, *dst = __sk_dst_get(sk);
1978
1979	if (dst && dst->ops->negative_advice) {
1980		ndst = dst->ops->negative_advice(dst);
1981
1982		if (ndst != dst) {
1983			rcu_assign_pointer(sk->sk_dst_cache, ndst);
1984			sk_tx_queue_clear(sk);
1985			sk->sk_dst_pending_confirm = 0;
1986		}
1987	}
1988}
1989
1990static inline void dst_negative_advice(struct sock *sk)
1991{
1992	sk_rethink_txhash(sk);
1993	__dst_negative_advice(sk);
1994}
1995
1996static inline void
1997__sk_dst_set(struct sock *sk, struct dst_entry *dst)
1998{
1999	struct dst_entry *old_dst;
2000
2001	sk_tx_queue_clear(sk);
2002	sk->sk_dst_pending_confirm = 0;
2003	old_dst = rcu_dereference_protected(sk->sk_dst_cache,
2004					    lockdep_sock_is_held(sk));
 
 
2005	rcu_assign_pointer(sk->sk_dst_cache, dst);
2006	dst_release(old_dst);
2007}
2008
2009static inline void
2010sk_dst_set(struct sock *sk, struct dst_entry *dst)
2011{
2012	struct dst_entry *old_dst;
2013
2014	sk_tx_queue_clear(sk);
2015	sk->sk_dst_pending_confirm = 0;
2016	old_dst = xchg((__force struct dst_entry **)&sk->sk_dst_cache, dst);
2017	dst_release(old_dst);
2018}
2019
2020static inline void
2021__sk_dst_reset(struct sock *sk)
2022{
2023	__sk_dst_set(sk, NULL);
2024}
2025
2026static inline void
2027sk_dst_reset(struct sock *sk)
2028{
2029	sk_dst_set(sk, NULL);
2030}
2031
2032struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
2033
2034struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
2035
2036static inline void sk_dst_confirm(struct sock *sk)
2037{
2038	if (!READ_ONCE(sk->sk_dst_pending_confirm))
2039		WRITE_ONCE(sk->sk_dst_pending_confirm, 1);
2040}
2041
2042static inline void sock_confirm_neigh(struct sk_buff *skb, struct neighbour *n)
2043{
2044	if (skb_get_dst_pending_confirm(skb)) {
2045		struct sock *sk = skb->sk;
2046		unsigned long now = jiffies;
2047
2048		/* avoid dirtying neighbour */
2049		if (READ_ONCE(n->confirmed) != now)
2050			WRITE_ONCE(n->confirmed, now);
2051		if (sk && READ_ONCE(sk->sk_dst_pending_confirm))
2052			WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2053	}
2054}
2055
2056bool sk_mc_loop(struct sock *sk);
2057
2058static inline bool sk_can_gso(const struct sock *sk)
2059{
2060	return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type);
2061}
2062
2063void sk_setup_caps(struct sock *sk, struct dst_entry *dst);
2064
2065static inline void sk_nocaps_add(struct sock *sk, netdev_features_t flags)
2066{
2067	sk->sk_route_nocaps |= flags;
2068	sk->sk_route_caps &= ~flags;
2069}
2070
2071static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
2072					   struct iov_iter *from, char *to,
2073					   int copy, int offset)
2074{
2075	if (skb->ip_summed == CHECKSUM_NONE) {
2076		__wsum csum = 0;
2077		if (!csum_and_copy_from_iter_full(to, copy, &csum, from))
2078			return -EFAULT;
 
2079		skb->csum = csum_block_add(skb->csum, csum, offset);
2080	} else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
2081		if (!copy_from_iter_full_nocache(to, copy, from))
 
2082			return -EFAULT;
2083	} else if (!copy_from_iter_full(to, copy, from))
2084		return -EFAULT;
2085
2086	return 0;
2087}
2088
2089static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
2090				       struct iov_iter *from, int copy)
2091{
2092	int err, offset = skb->len;
2093
2094	err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy),
2095				       copy, offset);
2096	if (err)
2097		__skb_trim(skb, offset);
2098
2099	return err;
2100}
2101
2102static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from,
2103					   struct sk_buff *skb,
2104					   struct page *page,
2105					   int off, int copy)
2106{
2107	int err;
2108
2109	err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off,
2110				       copy, skb->len);
2111	if (err)
2112		return err;
2113
2114	skb->len	     += copy;
2115	skb->data_len	     += copy;
2116	skb->truesize	     += copy;
2117	sk_wmem_queued_add(sk, copy);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2118	sk_mem_charge(sk, copy);
2119	return 0;
2120}
2121
2122/**
2123 * sk_wmem_alloc_get - returns write allocations
2124 * @sk: socket
2125 *
2126 * Return: sk_wmem_alloc minus initial offset of one
2127 */
2128static inline int sk_wmem_alloc_get(const struct sock *sk)
2129{
2130	return refcount_read(&sk->sk_wmem_alloc) - 1;
2131}
2132
2133/**
2134 * sk_rmem_alloc_get - returns read allocations
2135 * @sk: socket
2136 *
2137 * Return: sk_rmem_alloc
2138 */
2139static inline int sk_rmem_alloc_get(const struct sock *sk)
2140{
2141	return atomic_read(&sk->sk_rmem_alloc);
2142}
2143
2144/**
2145 * sk_has_allocations - check if allocations are outstanding
2146 * @sk: socket
2147 *
2148 * Return: true if socket has write or read allocations
2149 */
2150static inline bool sk_has_allocations(const struct sock *sk)
2151{
2152	return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk);
2153}
2154
2155/**
2156 * skwq_has_sleeper - check if there are any waiting processes
2157 * @wq: struct socket_wq
2158 *
2159 * Return: true if socket_wq has waiting processes
2160 *
2161 * The purpose of the skwq_has_sleeper and sock_poll_wait is to wrap the memory
2162 * barrier call. They were added due to the race found within the tcp code.
2163 *
2164 * Consider following tcp code paths::
 
 
2165 *
2166 *   CPU1                CPU2
2167 *   sys_select          receive packet
2168 *   ...                 ...
2169 *   __add_wait_queue    update tp->rcv_nxt
2170 *   ...                 ...
2171 *   tp->rcv_nxt check   sock_def_readable
2172 *   ...                 {
2173 *   schedule               rcu_read_lock();
2174 *                          wq = rcu_dereference(sk->sk_wq);
2175 *                          if (wq && waitqueue_active(&wq->wait))
2176 *                              wake_up_interruptible(&wq->wait)
2177 *                          ...
2178 *                       }
2179 *
2180 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
2181 * in its cache, and so does the tp->rcv_nxt update on CPU2 side.  The CPU1
2182 * could then endup calling schedule and sleep forever if there are no more
2183 * data on the socket.
2184 *
2185 */
2186static inline bool skwq_has_sleeper(struct socket_wq *wq)
2187{
2188	return wq && wq_has_sleeper(&wq->wait);
 
 
 
 
 
 
2189}
2190
2191/**
2192 * sock_poll_wait - place memory barrier behind the poll_wait call.
2193 * @filp:           file
2194 * @sock:           socket to wait on
2195 * @p:              poll_table
2196 *
2197 * See the comments in the wq_has_sleeper function.
2198 */
2199static inline void sock_poll_wait(struct file *filp, struct socket *sock,
2200				  poll_table *p)
2201{
2202	if (!poll_does_not_wait(p)) {
2203		poll_wait(filp, &sock->wq.wait, p);
2204		/* We need to be sure we are in sync with the
2205		 * socket flags modification.
2206		 *
2207		 * This memory barrier is paired in the wq_has_sleeper.
2208		 */
2209		smp_mb();
2210	}
2211}
2212
2213static inline void skb_set_hash_from_sk(struct sk_buff *skb, struct sock *sk)
2214{
2215	/* This pairs with WRITE_ONCE() in sk_set_txhash() */
2216	u32 txhash = READ_ONCE(sk->sk_txhash);
2217
2218	if (txhash) {
2219		skb->l4_hash = 1;
2220		skb->hash = txhash;
2221	}
2222}
2223
2224void skb_set_owner_w(struct sk_buff *skb, struct sock *sk);
2225
2226/*
2227 *	Queue a received datagram if it will fit. Stream and sequenced
2228 *	protocols can't normally use this as they need to fit buffers in
2229 *	and play with them.
2230 *
2231 *	Inlined as it's very short and called for pretty much every
2232 *	packet ever received.
2233 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2234static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
2235{
2236	skb_orphan(skb);
2237	skb->sk = sk;
2238	skb->destructor = sock_rfree;
2239	atomic_add(skb->truesize, &sk->sk_rmem_alloc);
2240	sk_mem_charge(sk, skb->truesize);
2241}
2242
2243static inline __must_check bool skb_set_owner_sk_safe(struct sk_buff *skb, struct sock *sk)
2244{
2245	if (sk && refcount_inc_not_zero(&sk->sk_refcnt)) {
2246		skb_orphan(skb);
2247		skb->destructor = sock_efree;
2248		skb->sk = sk;
2249		return true;
2250	}
2251	return false;
2252}
2253
2254void sk_reset_timer(struct sock *sk, struct timer_list *timer,
2255		    unsigned long expires);
2256
2257void sk_stop_timer(struct sock *sk, struct timer_list *timer);
2258
2259void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer);
2260
2261int __sk_queue_drop_skb(struct sock *sk, struct sk_buff_head *sk_queue,
2262			struct sk_buff *skb, unsigned int flags,
2263			void (*destructor)(struct sock *sk,
2264					   struct sk_buff *skb));
2265int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
2266int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
2267
2268int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
2269struct sk_buff *sock_dequeue_err_skb(struct sock *sk);
2270
2271/*
2272 *	Recover an error report and clear atomically
2273 */
2274
2275static inline int sock_error(struct sock *sk)
2276{
2277	int err;
2278
2279	/* Avoid an atomic operation for the common case.
2280	 * This is racy since another cpu/thread can change sk_err under us.
2281	 */
2282	if (likely(data_race(!sk->sk_err)))
2283		return 0;
2284
2285	err = xchg(&sk->sk_err, 0);
2286	return -err;
2287}
2288
2289void sk_error_report(struct sock *sk);
2290
2291static inline unsigned long sock_wspace(struct sock *sk)
2292{
2293	int amt = 0;
2294
2295	if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
2296		amt = sk->sk_sndbuf - refcount_read(&sk->sk_wmem_alloc);
2297		if (amt < 0)
2298			amt = 0;
2299	}
2300	return amt;
2301}
2302
2303/* Note:
2304 *  We use sk->sk_wq_raw, from contexts knowing this
2305 *  pointer is not NULL and cannot disappear/change.
2306 */
2307static inline void sk_set_bit(int nr, struct sock *sk)
2308{
2309	if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2310	    !sock_flag(sk, SOCK_FASYNC))
2311		return;
2312
2313	set_bit(nr, &sk->sk_wq_raw->flags);
2314}
2315
2316static inline void sk_clear_bit(int nr, struct sock *sk)
2317{
2318	if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2319	    !sock_flag(sk, SOCK_FASYNC))
2320		return;
2321
2322	clear_bit(nr, &sk->sk_wq_raw->flags);
2323}
2324
2325static inline void sk_wake_async(const struct sock *sk, int how, int band)
2326{
2327	if (sock_flag(sk, SOCK_FASYNC)) {
2328		rcu_read_lock();
2329		sock_wake_async(rcu_dereference(sk->sk_wq), how, band);
2330		rcu_read_unlock();
2331	}
2332}
2333
2334/* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might
2335 * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak.
2336 * Note: for send buffers, TCP works better if we can build two skbs at
2337 * minimum.
2338 */
2339#define TCP_SKB_MIN_TRUESIZE	(2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff)))
2340
2341#define SOCK_MIN_SNDBUF		(TCP_SKB_MIN_TRUESIZE * 2)
2342#define SOCK_MIN_RCVBUF		 TCP_SKB_MIN_TRUESIZE
2343
2344static inline void sk_stream_moderate_sndbuf(struct sock *sk)
2345{
2346	u32 val;
2347
2348	if (sk->sk_userlocks & SOCK_SNDBUF_LOCK)
2349		return;
2350
2351	val = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
2352
2353	WRITE_ONCE(sk->sk_sndbuf, max_t(u32, val, SOCK_MIN_SNDBUF));
2354}
2355
2356struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp,
2357				    bool force_schedule);
2358
2359/**
2360 * sk_page_frag - return an appropriate page_frag
2361 * @sk: socket
2362 *
2363 * Use the per task page_frag instead of the per socket one for
2364 * optimization when we know that we're in the normal context and owns
2365 * everything that's associated with %current.
2366 *
2367 * gfpflags_allow_blocking() isn't enough here as direct reclaim may nest
2368 * inside other socket operations and end up recursing into sk_page_frag()
2369 * while it's already in use.
2370 *
2371 * Return: a per task page_frag if context allows that,
2372 * otherwise a per socket one.
2373 */
2374static inline struct page_frag *sk_page_frag(struct sock *sk)
2375{
2376	if (gfpflags_normal_context(sk->sk_allocation))
2377		return &current->task_frag;
2378
2379	return &sk->sk_frag;
 
 
 
 
 
2380}
2381
2382bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag);
2383
2384/*
2385 *	Default write policy as shown to user space via poll/select/SIGIO
2386 */
2387static inline bool sock_writeable(const struct sock *sk)
2388{
2389	return refcount_read(&sk->sk_wmem_alloc) < (READ_ONCE(sk->sk_sndbuf) >> 1);
2390}
2391
2392static inline gfp_t gfp_any(void)
2393{
2394	return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2395}
2396
2397static inline long sock_rcvtimeo(const struct sock *sk, bool noblock)
2398{
2399	return noblock ? 0 : sk->sk_rcvtimeo;
2400}
2401
2402static inline long sock_sndtimeo(const struct sock *sk, bool noblock)
2403{
2404	return noblock ? 0 : sk->sk_sndtimeo;
2405}
2406
2407static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
2408{
2409	int v = waitall ? len : min_t(int, READ_ONCE(sk->sk_rcvlowat), len);
2410
2411	return v ?: 1;
2412}
2413
2414/* Alas, with timeout socket operations are not restartable.
2415 * Compare this to poll().
2416 */
2417static inline int sock_intr_errno(long timeo)
2418{
2419	return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
2420}
2421
2422struct sock_skb_cb {
2423	u32 dropcount;
2424};
2425
2426/* Store sock_skb_cb at the end of skb->cb[] so protocol families
2427 * using skb->cb[] would keep using it directly and utilize its
2428 * alignement guarantee.
2429 */
2430#define SOCK_SKB_CB_OFFSET ((sizeof_field(struct sk_buff, cb) - \
2431			    sizeof(struct sock_skb_cb)))
2432
2433#define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \
2434			    SOCK_SKB_CB_OFFSET))
2435
2436#define sock_skb_cb_check_size(size) \
2437	BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET)
2438
2439static inline void
2440sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb)
2441{
2442	SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, SOCK_RXQ_OVFL) ?
2443						atomic_read(&sk->sk_drops) : 0;
2444}
2445
2446static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb)
2447{
2448	int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs);
2449
2450	atomic_add(segs, &sk->sk_drops);
2451}
2452
2453static inline ktime_t sock_read_timestamp(struct sock *sk)
2454{
2455#if BITS_PER_LONG==32
2456	unsigned int seq;
2457	ktime_t kt;
2458
2459	do {
2460		seq = read_seqbegin(&sk->sk_stamp_seq);
2461		kt = sk->sk_stamp;
2462	} while (read_seqretry(&sk->sk_stamp_seq, seq));
2463
2464	return kt;
2465#else
2466	return READ_ONCE(sk->sk_stamp);
2467#endif
2468}
2469
2470static inline void sock_write_timestamp(struct sock *sk, ktime_t kt)
2471{
2472#if BITS_PER_LONG==32
2473	write_seqlock(&sk->sk_stamp_seq);
2474	sk->sk_stamp = kt;
2475	write_sequnlock(&sk->sk_stamp_seq);
2476#else
2477	WRITE_ONCE(sk->sk_stamp, kt);
2478#endif
2479}
2480
2481void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
2482			   struct sk_buff *skb);
2483void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
2484			     struct sk_buff *skb);
2485
2486static inline void
2487sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
2488{
2489	ktime_t kt = skb->tstamp;
2490	struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
2491
2492	/*
2493	 * generate control messages if
2494	 * - receive time stamping in software requested
 
2495	 * - software time stamp available and wanted
 
2496	 * - hardware time stamps available and wanted
 
 
2497	 */
2498	if (sock_flag(sk, SOCK_RCVTSTAMP) ||
2499	    (sk->sk_tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) ||
2500	    (kt && sk->sk_tsflags & SOF_TIMESTAMPING_SOFTWARE) ||
2501	    (hwtstamps->hwtstamp &&
2502	     (sk->sk_tsflags & SOF_TIMESTAMPING_RAW_HARDWARE)))
 
 
2503		__sock_recv_timestamp(msg, sk, skb);
2504	else
2505		sock_write_timestamp(sk, kt);
2506
2507	if (sock_flag(sk, SOCK_WIFI_STATUS) && skb->wifi_acked_valid)
2508		__sock_recv_wifi_status(msg, sk, skb);
2509}
2510
2511void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2512			      struct sk_buff *skb);
2513
2514#define SK_DEFAULT_STAMP (-1L * NSEC_PER_SEC)
2515static inline void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2516					  struct sk_buff *skb)
2517{
2518#define FLAGS_TS_OR_DROPS ((1UL << SOCK_RXQ_OVFL)			| \
2519			   (1UL << SOCK_RCVTSTAMP))
2520#define TSFLAGS_ANY	  (SOF_TIMESTAMPING_SOFTWARE			| \
2521			   SOF_TIMESTAMPING_RAW_HARDWARE)
 
 
2522
2523	if (sk->sk_flags & FLAGS_TS_OR_DROPS || sk->sk_tsflags & TSFLAGS_ANY)
2524		__sock_recv_ts_and_drops(msg, sk, skb);
2525	else if (unlikely(sock_flag(sk, SOCK_TIMESTAMP)))
2526		sock_write_timestamp(sk, skb->tstamp);
2527	else if (unlikely(sk->sk_stamp == SK_DEFAULT_STAMP))
2528		sock_write_timestamp(sk, 0);
2529}
2530
2531void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags);
2532
2533/**
2534 * _sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
2535 * @sk:		socket sending this packet
2536 * @tsflags:	timestamping flags to use
2537 * @tx_flags:	completed with instructions for time stamping
2538 * @tskey:      filled in with next sk_tskey (not for TCP, which uses seqno)
2539 *
2540 * Note: callers should take care of initial ``*tx_flags`` value (usually 0)
2541 */
2542static inline void _sock_tx_timestamp(struct sock *sk, __u16 tsflags,
2543				      __u8 *tx_flags, __u32 *tskey)
2544{
2545	if (unlikely(tsflags)) {
2546		__sock_tx_timestamp(tsflags, tx_flags);
2547		if (tsflags & SOF_TIMESTAMPING_OPT_ID && tskey &&
2548		    tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK)
2549			*tskey = sk->sk_tskey++;
2550	}
2551	if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS)))
2552		*tx_flags |= SKBTX_WIFI_STATUS;
2553}
2554
2555static inline void sock_tx_timestamp(struct sock *sk, __u16 tsflags,
2556				     __u8 *tx_flags)
2557{
2558	_sock_tx_timestamp(sk, tsflags, tx_flags, NULL);
2559}
2560
2561static inline void skb_setup_tx_timestamp(struct sk_buff *skb, __u16 tsflags)
2562{
2563	_sock_tx_timestamp(skb->sk, tsflags, &skb_shinfo(skb)->tx_flags,
2564			   &skb_shinfo(skb)->tskey);
2565}
2566
2567DECLARE_STATIC_KEY_FALSE(tcp_rx_skb_cache_key);
2568/**
2569 * sk_eat_skb - Release a skb if it is no longer needed
2570 * @sk: socket to eat this skb from
2571 * @skb: socket buffer to eat
 
2572 *
2573 * This routine must be called with interrupts disabled or with the socket
2574 * locked so that the sk_buff queue operation is ok.
2575*/
2576static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb)
 
 
 
 
 
 
 
 
 
 
2577{
2578	__skb_unlink(skb, &sk->sk_receive_queue);
2579	if (static_branch_unlikely(&tcp_rx_skb_cache_key) &&
2580	    !sk->sk_rx_skb_cache) {
2581		sk->sk_rx_skb_cache = skb;
2582		skb_orphan(skb);
2583		return;
2584	}
2585	__kfree_skb(skb);
2586}
 
2587
2588static inline
2589struct net *sock_net(const struct sock *sk)
2590{
2591	return read_pnet(&sk->sk_net);
2592}
2593
2594static inline
2595void sock_net_set(struct sock *sk, struct net *net)
2596{
2597	write_pnet(&sk->sk_net, net);
2598}
2599
2600static inline bool
2601skb_sk_is_prefetched(struct sk_buff *skb)
2602{
2603#ifdef CONFIG_INET
2604	return skb->destructor == sock_pfree;
2605#else
2606	return false;
2607#endif /* CONFIG_INET */
2608}
2609
2610/* This helper checks if a socket is a full socket,
2611 * ie _not_ a timewait or request socket.
2612 */
2613static inline bool sk_fullsock(const struct sock *sk)
2614{
2615	return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV);
2616}
2617
2618static inline bool
2619sk_is_refcounted(struct sock *sk)
2620{
2621	/* Only full sockets have sk->sk_flags. */
2622	return !sk_fullsock(sk) || !sock_flag(sk, SOCK_RCU_FREE);
2623}
2624
2625/**
2626 * skb_steal_sock - steal a socket from an sk_buff
2627 * @skb: sk_buff to steal the socket from
2628 * @refcounted: is set to true if the socket is reference-counted
2629 */
2630static inline struct sock *
2631skb_steal_sock(struct sk_buff *skb, bool *refcounted)
2632{
2633	if (skb->sk) {
2634		struct sock *sk = skb->sk;
2635
2636		*refcounted = true;
2637		if (skb_sk_is_prefetched(skb))
2638			*refcounted = sk_is_refcounted(sk);
2639		skb->destructor = NULL;
2640		skb->sk = NULL;
2641		return sk;
2642	}
2643	*refcounted = false;
2644	return NULL;
2645}
2646
2647/* Checks if this SKB belongs to an HW offloaded socket
2648 * and whether any SW fallbacks are required based on dev.
2649 * Check decrypted mark in case skb_orphan() cleared socket.
2650 */
2651static inline struct sk_buff *sk_validate_xmit_skb(struct sk_buff *skb,
2652						   struct net_device *dev)
2653{
2654#ifdef CONFIG_SOCK_VALIDATE_XMIT
2655	struct sock *sk = skb->sk;
2656
2657	if (sk && sk_fullsock(sk) && sk->sk_validate_xmit_skb) {
2658		skb = sk->sk_validate_xmit_skb(sk, dev, skb);
2659#ifdef CONFIG_TLS_DEVICE
2660	} else if (unlikely(skb->decrypted)) {
2661		pr_warn_ratelimited("unencrypted skb with no associated socket - dropping\n");
2662		kfree_skb(skb);
2663		skb = NULL;
2664#endif
2665	}
2666#endif
2667
2668	return skb;
2669}
2670
2671/* This helper checks if a socket is a LISTEN or NEW_SYN_RECV
2672 * SYNACK messages can be attached to either ones (depending on SYNCOOKIE)
2673 */
2674static inline bool sk_listener(const struct sock *sk)
2675{
2676	return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV);
2677}
2678
2679void sock_enable_timestamp(struct sock *sk, enum sock_flags flag);
2680int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level,
2681		       int type);
2682
2683bool sk_ns_capable(const struct sock *sk,
2684		   struct user_namespace *user_ns, int cap);
2685bool sk_capable(const struct sock *sk, int cap);
2686bool sk_net_capable(const struct sock *sk, int cap);
2687
2688void sk_get_meminfo(const struct sock *sk, u32 *meminfo);
2689
2690/* Take into consideration the size of the struct sk_buff overhead in the
2691 * determination of these values, since that is non-constant across
2692 * platforms.  This makes socket queueing behavior and performance
2693 * not depend upon such differences.
2694 */
2695#define _SK_MEM_PACKETS		256
2696#define _SK_MEM_OVERHEAD	SKB_TRUESIZE(256)
2697#define SK_WMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2698#define SK_RMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2699
2700extern __u32 sysctl_wmem_max;
2701extern __u32 sysctl_rmem_max;
2702
2703extern int sysctl_tstamp_allow_data;
 
2704extern int sysctl_optmem_max;
2705
2706extern __u32 sysctl_wmem_default;
2707extern __u32 sysctl_rmem_default;
2708
2709DECLARE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
2710
2711static inline int sk_get_wmem0(const struct sock *sk, const struct proto *proto)
2712{
2713	/* Does this proto have per netns sysctl_wmem ? */
2714	if (proto->sysctl_wmem_offset)
2715		return *(int *)((void *)sock_net(sk) + proto->sysctl_wmem_offset);
2716
2717	return *proto->sysctl_wmem;
2718}
2719
2720static inline int sk_get_rmem0(const struct sock *sk, const struct proto *proto)
2721{
2722	/* Does this proto have per netns sysctl_rmem ? */
2723	if (proto->sysctl_rmem_offset)
2724		return *(int *)((void *)sock_net(sk) + proto->sysctl_rmem_offset);
2725
2726	return *proto->sysctl_rmem;
2727}
2728
2729/* Default TCP Small queue budget is ~1 ms of data (1sec >> 10)
2730 * Some wifi drivers need to tweak it to get more chunks.
2731 * They can use this helper from their ndo_start_xmit()
2732 */
2733static inline void sk_pacing_shift_update(struct sock *sk, int val)
2734{
2735	if (!sk || !sk_fullsock(sk) || READ_ONCE(sk->sk_pacing_shift) == val)
2736		return;
2737	WRITE_ONCE(sk->sk_pacing_shift, val);
2738}
2739
2740/* if a socket is bound to a device, check that the given device
2741 * index is either the same or that the socket is bound to an L3
2742 * master device and the given device index is also enslaved to
2743 * that L3 master
2744 */
2745static inline bool sk_dev_equal_l3scope(struct sock *sk, int dif)
2746{
2747	int mdif;
2748
2749	if (!sk->sk_bound_dev_if || sk->sk_bound_dev_if == dif)
2750		return true;
2751
2752	mdif = l3mdev_master_ifindex_by_index(sock_net(sk), dif);
2753	if (mdif && mdif == sk->sk_bound_dev_if)
2754		return true;
2755
2756	return false;
2757}
2758
2759void sock_def_readable(struct sock *sk);
2760
2761int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk);
2762void sock_set_timestamp(struct sock *sk, int optname, bool valbool);
2763int sock_set_timestamping(struct sock *sk, int optname,
2764			  struct so_timestamping timestamping);
2765
2766void sock_enable_timestamps(struct sock *sk);
2767void sock_no_linger(struct sock *sk);
2768void sock_set_keepalive(struct sock *sk);
2769void sock_set_priority(struct sock *sk, u32 priority);
2770void sock_set_rcvbuf(struct sock *sk, int val);
2771void sock_set_mark(struct sock *sk, u32 val);
2772void sock_set_reuseaddr(struct sock *sk);
2773void sock_set_reuseport(struct sock *sk);
2774void sock_set_sndtimeo(struct sock *sk, s64 secs);
2775
2776int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len);
2777
2778#endif	/* _SOCK_H */
v3.5.6
 
   1/*
   2 * INET		An implementation of the TCP/IP protocol suite for the LINUX
   3 *		operating system.  INET is implemented using the  BSD Socket
   4 *		interface as the means of communication with the user level.
   5 *
   6 *		Definitions for the AF_INET socket handler.
   7 *
   8 * Version:	@(#)sock.h	1.0.4	05/13/93
   9 *
  10 * Authors:	Ross Biro
  11 *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
  12 *		Corey Minyard <wf-rch!minyard@relay.EU.net>
  13 *		Florian La Roche <flla@stud.uni-sb.de>
  14 *
  15 * Fixes:
  16 *		Alan Cox	:	Volatiles in skbuff pointers. See
  17 *					skbuff comments. May be overdone,
  18 *					better to prove they can be removed
  19 *					than the reverse.
  20 *		Alan Cox	:	Added a zapped field for tcp to note
  21 *					a socket is reset and must stay shut up
  22 *		Alan Cox	:	New fields for options
  23 *	Pauline Middelink	:	identd support
  24 *		Alan Cox	:	Eliminate low level recv/recvfrom
  25 *		David S. Miller	:	New socket lookup architecture.
  26 *              Steve Whitehouse:       Default routines for sock_ops
  27 *              Arnaldo C. Melo :	removed net_pinfo, tp_pinfo and made
  28 *              			protinfo be just a void pointer, as the
  29 *              			protocol specific parts were moved to
  30 *              			respective headers and ipv4/v6, etc now
  31 *              			use private slabcaches for its socks
  32 *              Pedro Hortas	:	New flags field for socket options
  33 *
  34 *
  35 *		This program is free software; you can redistribute it and/or
  36 *		modify it under the terms of the GNU General Public License
  37 *		as published by the Free Software Foundation; either version
  38 *		2 of the License, or (at your option) any later version.
  39 */
  40#ifndef _SOCK_H
  41#define _SOCK_H
  42
  43#include <linux/hardirq.h>
  44#include <linux/kernel.h>
  45#include <linux/list.h>
  46#include <linux/list_nulls.h>
  47#include <linux/timer.h>
  48#include <linux/cache.h>
  49#include <linux/bitops.h>
  50#include <linux/lockdep.h>
  51#include <linux/netdevice.h>
  52#include <linux/skbuff.h>	/* struct sk_buff */
  53#include <linux/mm.h>
  54#include <linux/security.h>
  55#include <linux/slab.h>
  56#include <linux/uaccess.h>
 
  57#include <linux/memcontrol.h>
  58#include <linux/res_counter.h>
  59#include <linux/static_key.h>
  60#include <linux/aio.h>
  61#include <linux/sched.h>
  62
 
 
  63#include <linux/filter.h>
  64#include <linux/rculist_nulls.h>
  65#include <linux/poll.h>
  66
 
  67#include <linux/atomic.h>
 
  68#include <net/dst.h>
  69#include <net/checksum.h>
 
 
 
  70
  71struct cgroup;
  72struct cgroup_subsys;
  73#ifdef CONFIG_NET
  74int mem_cgroup_sockets_init(struct mem_cgroup *memcg, struct cgroup_subsys *ss);
  75void mem_cgroup_sockets_destroy(struct mem_cgroup *memcg);
  76#else
  77static inline
  78int mem_cgroup_sockets_init(struct mem_cgroup *memcg, struct cgroup_subsys *ss)
  79{
  80	return 0;
  81}
  82static inline
  83void mem_cgroup_sockets_destroy(struct mem_cgroup *memcg)
  84{
  85}
  86#endif
  87/*
  88 * This structure really needs to be cleaned up.
  89 * Most of it is for TCP, and not used by any of
  90 * the other protocols.
  91 */
  92
  93/* Define this to get the SOCK_DBG debugging facility. */
  94#define SOCK_DEBUGGING
  95#ifdef SOCK_DEBUGGING
  96#define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \
  97					printk(KERN_DEBUG msg); } while (0)
  98#else
  99/* Validate arguments and do nothing */
 100static inline __printf(2, 3)
 101void SOCK_DEBUG(const struct sock *sk, const char *msg, ...)
 102{
 103}
 104#endif
 105
 106/* This is the per-socket lock.  The spinlock provides a synchronization
 107 * between user contexts and software interrupt processing, whereas the
 108 * mini-semaphore synchronizes multiple users amongst themselves.
 109 */
 110typedef struct {
 111	spinlock_t		slock;
 112	int			owned;
 113	wait_queue_head_t	wq;
 114	/*
 115	 * We express the mutex-alike socket_lock semantics
 116	 * to the lock validator by explicitly managing
 117	 * the slock as a lock variant (in addition to
 118	 * the slock itself):
 119	 */
 120#ifdef CONFIG_DEBUG_LOCK_ALLOC
 121	struct lockdep_map dep_map;
 122#endif
 123} socket_lock_t;
 124
 125struct sock;
 126struct proto;
 127struct net;
 128
 
 
 
 129/**
 130 *	struct sock_common - minimal network layer representation of sockets
 131 *	@skc_daddr: Foreign IPv4 addr
 132 *	@skc_rcv_saddr: Bound local IPv4 addr
 
 133 *	@skc_hash: hash value used with various protocol lookup tables
 134 *	@skc_u16hashes: two u16 hash values used by UDP lookup tables
 
 
 
 135 *	@skc_family: network address family
 136 *	@skc_state: Connection state
 137 *	@skc_reuse: %SO_REUSEADDR setting
 
 
 
 138 *	@skc_bound_dev_if: bound device index if != 0
 139 *	@skc_bind_node: bind hash linkage for various protocol lookup tables
 140 *	@skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol
 141 *	@skc_prot: protocol handlers inside a network family
 142 *	@skc_net: reference to the network namespace of this socket
 
 
 
 143 *	@skc_node: main hash linkage for various protocol lookup tables
 144 *	@skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol
 145 *	@skc_tx_queue_mapping: tx queue number for this connection
 
 
 
 
 
 
 
 
 
 
 
 
 
 146 *	@skc_refcnt: reference count
 147 *
 148 *	This is the minimal network layer representation of sockets, the header
 149 *	for struct sock and struct inet_timewait_sock.
 150 */
 151struct sock_common {
 152	/* skc_daddr and skc_rcv_saddr must be grouped :
 153	 * cf INET_MATCH() and INET_TW_MATCH()
 154	 */
 155	__be32			skc_daddr;
 156	__be32			skc_rcv_saddr;
 157
 
 
 
 
 158	union  {
 159		unsigned int	skc_hash;
 160		__u16		skc_u16hashes[2];
 161	};
 
 
 
 
 
 
 
 
 
 162	unsigned short		skc_family;
 163	volatile unsigned char	skc_state;
 164	unsigned char		skc_reuse;
 
 
 
 165	int			skc_bound_dev_if;
 166	union {
 167		struct hlist_node	skc_bind_node;
 168		struct hlist_nulls_node skc_portaddr_node;
 169	};
 170	struct proto		*skc_prot;
 171#ifdef CONFIG_NET_NS
 172	struct net	 	*skc_net;
 
 
 
 173#endif
 
 
 
 
 
 
 
 
 
 
 
 
 
 174	/*
 175	 * fields between dontcopy_begin/dontcopy_end
 176	 * are not copied in sock_copy()
 177	 */
 178	/* private: */
 179	int			skc_dontcopy_begin[0];
 180	/* public: */
 181	union {
 182		struct hlist_node	skc_node;
 183		struct hlist_nulls_node skc_nulls_node;
 184	};
 185	int			skc_tx_queue_mapping;
 186	atomic_t		skc_refcnt;
 
 
 
 
 
 
 
 
 
 187	/* private: */
 188	int                     skc_dontcopy_end[0];
 
 
 
 
 
 189	/* public: */
 190};
 191
 192struct cg_proto;
 
 193/**
 194  *	struct sock - network layer representation of sockets
 195  *	@__sk_common: shared layout with inet_timewait_sock
 196  *	@sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
 197  *	@sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
 198  *	@sk_lock:	synchronizer
 
 199  *	@sk_rcvbuf: size of receive buffer in bytes
 200  *	@sk_wq: sock wait queue and async head
 
 201  *	@sk_dst_cache: destination cache
 202  *	@sk_dst_lock: destination cache lock
 203  *	@sk_policy: flow policy
 
 204  *	@sk_receive_queue: incoming packets
 205  *	@sk_wmem_alloc: transmit queue bytes committed
 
 206  *	@sk_write_queue: Packet sending queue
 207  *	@sk_async_wait_queue: DMA copied packets
 208  *	@sk_omem_alloc: "o" is "option" or "other"
 209  *	@sk_wmem_queued: persistent queue size
 210  *	@sk_forward_alloc: space allocated forward
 
 
 211  *	@sk_allocation: allocation mode
 
 
 
 212  *	@sk_sndbuf: size of send buffer in bytes
 213  *	@sk_flags: %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE,
 214  *		   %SO_OOBINLINE settings, %SO_TIMESTAMPING settings
 215  *	@sk_no_check: %SO_NO_CHECK setting, wether or not checkup packets
 
 216  *	@sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
 217  *	@sk_route_nocaps: forbidden route capabilities (e.g NETIF_F_GSO_MASK)
 
 
 218  *	@sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
 219  *	@sk_gso_max_size: Maximum GSO segment size to build
 220  *	@sk_gso_max_segs: Maximum number of GSO segments
 
 221  *	@sk_lingertime: %SO_LINGER l_linger setting
 222  *	@sk_backlog: always used with the per-socket spinlock held
 223  *	@sk_callback_lock: used with the callbacks in the end of this struct
 224  *	@sk_error_queue: rarely used
 225  *	@sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt,
 226  *			  IPV6_ADDRFORM for instance)
 227  *	@sk_err: last error
 228  *	@sk_err_soft: errors that don't cause failure but are the cause of a
 229  *		      persistent failure not just 'timed out'
 230  *	@sk_drops: raw/udp drops counter
 231  *	@sk_ack_backlog: current listen backlog
 232  *	@sk_max_ack_backlog: listen backlog set in listen()
 
 
 
 233  *	@sk_priority: %SO_PRIORITY setting
 234  *	@sk_cgrp_prioidx: socket group's priority map index
 235  *	@sk_type: socket type (%SOCK_STREAM, etc)
 236  *	@sk_protocol: which protocol this socket belongs in this network family
 237  *	@sk_peer_pid: &struct pid for this socket's peer
 238  *	@sk_peer_cred: %SO_PEERCRED setting
 239  *	@sk_rcvlowat: %SO_RCVLOWAT setting
 240  *	@sk_rcvtimeo: %SO_RCVTIMEO setting
 241  *	@sk_sndtimeo: %SO_SNDTIMEO setting
 242  *	@sk_rxhash: flow hash received from netif layer
 243  *	@sk_filter: socket filtering instructions
 244  *	@sk_protinfo: private area, net family specific, when not using slab
 245  *	@sk_timer: sock cleanup timer
 246  *	@sk_stamp: time stamp of last packet received
 
 
 
 
 
 
 247  *	@sk_socket: Identd and reporting IO signals
 248  *	@sk_user_data: RPC layer private data
 249  *	@sk_sndmsg_page: cached page for sendmsg
 250  *	@sk_sndmsg_off: cached offset for sendmsg
 251  *	@sk_peek_off: current peek_offset value
 252  *	@sk_send_head: front of stuff to transmit
 
 
 253  *	@sk_security: used by security modules
 254  *	@sk_mark: generic packet mark
 255  *	@sk_classid: this socket's cgroup classid
 256  *	@sk_cgrp: this socket's cgroup-specific proto data
 257  *	@sk_write_pending: a write to stream socket waits to start
 258  *	@sk_state_change: callback to indicate change in the state of the sock
 259  *	@sk_data_ready: callback to indicate there is data to be processed
 260  *	@sk_write_space: callback to indicate there is bf sending space available
 261  *	@sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
 262  *	@sk_backlog_rcv: callback to process the backlog
 
 263  *	@sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
 264 */
 
 
 
 
 
 
 
 265struct sock {
 266	/*
 267	 * Now struct inet_timewait_sock also uses sock_common, so please just
 268	 * don't add nothing before this first member (__sk_common) --acme
 269	 */
 270	struct sock_common	__sk_common;
 271#define sk_node			__sk_common.skc_node
 272#define sk_nulls_node		__sk_common.skc_nulls_node
 273#define sk_refcnt		__sk_common.skc_refcnt
 274#define sk_tx_queue_mapping	__sk_common.skc_tx_queue_mapping
 
 
 
 275
 276#define sk_dontcopy_begin	__sk_common.skc_dontcopy_begin
 277#define sk_dontcopy_end		__sk_common.skc_dontcopy_end
 278#define sk_hash			__sk_common.skc_hash
 
 
 
 
 
 
 279#define sk_family		__sk_common.skc_family
 280#define sk_state		__sk_common.skc_state
 281#define sk_reuse		__sk_common.skc_reuse
 
 
 
 282#define sk_bound_dev_if		__sk_common.skc_bound_dev_if
 283#define sk_bind_node		__sk_common.skc_bind_node
 284#define sk_prot			__sk_common.skc_prot
 285#define sk_net			__sk_common.skc_net
 
 
 
 
 
 
 
 286	socket_lock_t		sk_lock;
 
 
 
 
 287	struct sk_buff_head	sk_receive_queue;
 288	/*
 289	 * The backlog queue is special, it is always used with
 290	 * the per-socket spinlock held and requires low latency
 291	 * access. Therefore we special case it's implementation.
 292	 * Note : rmem_alloc is in this structure to fill a hole
 293	 * on 64bit arches, not because its logically part of
 294	 * backlog.
 295	 */
 296	struct {
 297		atomic_t	rmem_alloc;
 298		int		len;
 299		struct sk_buff	*head;
 300		struct sk_buff	*tail;
 301	} sk_backlog;
 302#define sk_rmem_alloc sk_backlog.rmem_alloc
 
 303	int			sk_forward_alloc;
 304#ifdef CONFIG_RPS
 305	__u32			sk_rxhash;
 
 
 306#endif
 307	atomic_t		sk_drops;
 308	int			sk_rcvbuf;
 309
 310	struct sk_filter __rcu	*sk_filter;
 311	struct socket_wq __rcu	*sk_wq;
 312
 313#ifdef CONFIG_NET_DMA
 314	struct sk_buff_head	sk_async_wait_queue;
 315#endif
 316
 317#ifdef CONFIG_XFRM
 318	struct xfrm_policy	*sk_policy[2];
 319#endif
 320	unsigned long 		sk_flags;
 321	struct dst_entry	*sk_dst_cache;
 322	spinlock_t		sk_dst_lock;
 323	atomic_t		sk_wmem_alloc;
 324	atomic_t		sk_omem_alloc;
 325	int			sk_sndbuf;
 
 
 
 
 
 
 
 
 
 
 326	struct sk_buff_head	sk_write_queue;
 327	kmemcheck_bitfield_begin(flags);
 328	unsigned int		sk_shutdown  : 2,
 329				sk_no_check  : 2,
 330				sk_userlocks : 4,
 331				sk_protocol  : 8,
 332				sk_type      : 16;
 333	kmemcheck_bitfield_end(flags);
 334	int			sk_wmem_queued;
 335	gfp_t			sk_allocation;
 
 
 336	netdev_features_t	sk_route_caps;
 337	netdev_features_t	sk_route_nocaps;
 
 338	int			sk_gso_type;
 339	unsigned int		sk_gso_max_size;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 340	u16			sk_gso_max_segs;
 341	int			sk_rcvlowat;
 342	unsigned long	        sk_lingertime;
 343	struct sk_buff_head	sk_error_queue;
 344	struct proto		*sk_prot_creator;
 345	rwlock_t		sk_callback_lock;
 346	int			sk_err,
 347				sk_err_soft;
 348	unsigned short		sk_ack_backlog;
 349	unsigned short		sk_max_ack_backlog;
 350	__u32			sk_priority;
 351#ifdef CONFIG_CGROUPS
 352	__u32			sk_cgrp_prioidx;
 
 353#endif
 
 354	struct pid		*sk_peer_pid;
 355	const struct cred	*sk_peer_cred;
 
 356	long			sk_rcvtimeo;
 357	long			sk_sndtimeo;
 358	void			*sk_protinfo;
 359	struct timer_list	sk_timer;
 360	ktime_t			sk_stamp;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 361	struct socket		*sk_socket;
 362	void			*sk_user_data;
 363	struct page		*sk_sndmsg_page;
 364	struct sk_buff		*sk_send_head;
 365	__u32			sk_sndmsg_off;
 366	__s32			sk_peek_off;
 367	int			sk_write_pending;
 368#ifdef CONFIG_SECURITY
 369	void			*sk_security;
 370#endif
 371	__u32			sk_mark;
 372	u32			sk_classid;
 373	struct cg_proto		*sk_cgrp;
 374	void			(*sk_state_change)(struct sock *sk);
 375	void			(*sk_data_ready)(struct sock *sk, int bytes);
 376	void			(*sk_write_space)(struct sock *sk);
 377	void			(*sk_error_report)(struct sock *sk);
 378	int			(*sk_backlog_rcv)(struct sock *sk,
 379						  struct sk_buff *skb);
 
 
 
 
 
 380	void                    (*sk_destruct)(struct sock *sk);
 
 
 
 
 
 
 
 
 
 
 
 381};
 382
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 383/*
 384 * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK
 385 * or not whether his port will be reused by someone else. SK_FORCE_REUSE
 386 * on a socket means that the socket will reuse everybody else's port
 387 * without looking at the other's sk_reuse value.
 388 */
 389
 390#define SK_NO_REUSE	0
 391#define SK_CAN_REUSE	1
 392#define SK_FORCE_REUSE	2
 393
 
 
 394static inline int sk_peek_offset(struct sock *sk, int flags)
 395{
 396	if ((flags & MSG_PEEK) && (sk->sk_peek_off >= 0))
 397		return sk->sk_peek_off;
 398	else
 399		return 0;
 
 400}
 401
 402static inline void sk_peek_offset_bwd(struct sock *sk, int val)
 403{
 404	if (sk->sk_peek_off >= 0) {
 405		if (sk->sk_peek_off >= val)
 406			sk->sk_peek_off -= val;
 407		else
 408			sk->sk_peek_off = 0;
 409	}
 410}
 411
 412static inline void sk_peek_offset_fwd(struct sock *sk, int val)
 413{
 414	if (sk->sk_peek_off >= 0)
 415		sk->sk_peek_off += val;
 416}
 417
 418/*
 419 * Hashed lists helper routines
 420 */
 421static inline struct sock *sk_entry(const struct hlist_node *node)
 422{
 423	return hlist_entry(node, struct sock, sk_node);
 424}
 425
 426static inline struct sock *__sk_head(const struct hlist_head *head)
 427{
 428	return hlist_entry(head->first, struct sock, sk_node);
 429}
 430
 431static inline struct sock *sk_head(const struct hlist_head *head)
 432{
 433	return hlist_empty(head) ? NULL : __sk_head(head);
 434}
 435
 436static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head)
 437{
 438	return hlist_nulls_entry(head->first, struct sock, sk_nulls_node);
 439}
 440
 441static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head)
 442{
 443	return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head);
 444}
 445
 446static inline struct sock *sk_next(const struct sock *sk)
 447{
 448	return sk->sk_node.next ?
 449		hlist_entry(sk->sk_node.next, struct sock, sk_node) : NULL;
 450}
 451
 452static inline struct sock *sk_nulls_next(const struct sock *sk)
 453{
 454	return (!is_a_nulls(sk->sk_nulls_node.next)) ?
 455		hlist_nulls_entry(sk->sk_nulls_node.next,
 456				  struct sock, sk_nulls_node) :
 457		NULL;
 458}
 459
 460static inline bool sk_unhashed(const struct sock *sk)
 461{
 462	return hlist_unhashed(&sk->sk_node);
 463}
 464
 465static inline bool sk_hashed(const struct sock *sk)
 466{
 467	return !sk_unhashed(sk);
 468}
 469
 470static inline void sk_node_init(struct hlist_node *node)
 471{
 472	node->pprev = NULL;
 473}
 474
 475static inline void sk_nulls_node_init(struct hlist_nulls_node *node)
 476{
 477	node->pprev = NULL;
 478}
 479
 480static inline void __sk_del_node(struct sock *sk)
 481{
 482	__hlist_del(&sk->sk_node);
 483}
 484
 485/* NB: equivalent to hlist_del_init_rcu */
 486static inline bool __sk_del_node_init(struct sock *sk)
 487{
 488	if (sk_hashed(sk)) {
 489		__sk_del_node(sk);
 490		sk_node_init(&sk->sk_node);
 491		return true;
 492	}
 493	return false;
 494}
 495
 496/* Grab socket reference count. This operation is valid only
 497   when sk is ALREADY grabbed f.e. it is found in hash table
 498   or a list and the lookup is made under lock preventing hash table
 499   modifications.
 500 */
 501
 502static inline void sock_hold(struct sock *sk)
 503{
 504	atomic_inc(&sk->sk_refcnt);
 505}
 506
 507/* Ungrab socket in the context, which assumes that socket refcnt
 508   cannot hit zero, f.e. it is true in context of any socketcall.
 509 */
 510static inline void __sock_put(struct sock *sk)
 511{
 512	atomic_dec(&sk->sk_refcnt);
 513}
 514
 515static inline bool sk_del_node_init(struct sock *sk)
 516{
 517	bool rc = __sk_del_node_init(sk);
 518
 519	if (rc) {
 520		/* paranoid for a while -acme */
 521		WARN_ON(atomic_read(&sk->sk_refcnt) == 1);
 522		__sock_put(sk);
 523	}
 524	return rc;
 525}
 526#define sk_del_node_init_rcu(sk)	sk_del_node_init(sk)
 527
 528static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk)
 529{
 530	if (sk_hashed(sk)) {
 531		hlist_nulls_del_init_rcu(&sk->sk_nulls_node);
 532		return true;
 533	}
 534	return false;
 535}
 536
 537static inline bool sk_nulls_del_node_init_rcu(struct sock *sk)
 538{
 539	bool rc = __sk_nulls_del_node_init_rcu(sk);
 540
 541	if (rc) {
 542		/* paranoid for a while -acme */
 543		WARN_ON(atomic_read(&sk->sk_refcnt) == 1);
 544		__sock_put(sk);
 545	}
 546	return rc;
 547}
 548
 549static inline void __sk_add_node(struct sock *sk, struct hlist_head *list)
 550{
 551	hlist_add_head(&sk->sk_node, list);
 552}
 553
 554static inline void sk_add_node(struct sock *sk, struct hlist_head *list)
 555{
 556	sock_hold(sk);
 557	__sk_add_node(sk, list);
 558}
 559
 560static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list)
 561{
 562	sock_hold(sk);
 563	hlist_add_head_rcu(&sk->sk_node, list);
 
 
 
 
 
 
 
 
 
 
 564}
 565
 566static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
 567{
 568	hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list);
 569}
 570
 
 
 
 
 
 571static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
 572{
 573	sock_hold(sk);
 574	__sk_nulls_add_node_rcu(sk, list);
 575}
 576
 577static inline void __sk_del_bind_node(struct sock *sk)
 578{
 579	__hlist_del(&sk->sk_bind_node);
 580}
 581
 582static inline void sk_add_bind_node(struct sock *sk,
 583					struct hlist_head *list)
 584{
 585	hlist_add_head(&sk->sk_bind_node, list);
 586}
 587
 588#define sk_for_each(__sk, node, list) \
 589	hlist_for_each_entry(__sk, node, list, sk_node)
 590#define sk_for_each_rcu(__sk, node, list) \
 591	hlist_for_each_entry_rcu(__sk, node, list, sk_node)
 592#define sk_nulls_for_each(__sk, node, list) \
 593	hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)
 594#define sk_nulls_for_each_rcu(__sk, node, list) \
 595	hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)
 596#define sk_for_each_from(__sk, node) \
 597	if (__sk && ({ node = &(__sk)->sk_node; 1; })) \
 598		hlist_for_each_entry_from(__sk, node, sk_node)
 599#define sk_nulls_for_each_from(__sk, node) \
 600	if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \
 601		hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node)
 602#define sk_for_each_safe(__sk, node, tmp, list) \
 603	hlist_for_each_entry_safe(__sk, node, tmp, list, sk_node)
 604#define sk_for_each_bound(__sk, node, list) \
 605	hlist_for_each_entry(__sk, node, list, sk_bind_node)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 606
 607/* Sock flags */
 608enum sock_flags {
 609	SOCK_DEAD,
 610	SOCK_DONE,
 611	SOCK_URGINLINE,
 612	SOCK_KEEPOPEN,
 613	SOCK_LINGER,
 614	SOCK_DESTROY,
 615	SOCK_BROADCAST,
 616	SOCK_TIMESTAMP,
 617	SOCK_ZAPPED,
 618	SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */
 619	SOCK_DBG, /* %SO_DEBUG setting */
 620	SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
 621	SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */
 622	SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
 623	SOCK_QUEUE_SHRUNK, /* write queue has been shrunk recently */
 624	SOCK_TIMESTAMPING_TX_HARDWARE,  /* %SOF_TIMESTAMPING_TX_HARDWARE */
 625	SOCK_TIMESTAMPING_TX_SOFTWARE,  /* %SOF_TIMESTAMPING_TX_SOFTWARE */
 626	SOCK_TIMESTAMPING_RX_HARDWARE,  /* %SOF_TIMESTAMPING_RX_HARDWARE */
 627	SOCK_TIMESTAMPING_RX_SOFTWARE,  /* %SOF_TIMESTAMPING_RX_SOFTWARE */
 628	SOCK_TIMESTAMPING_SOFTWARE,     /* %SOF_TIMESTAMPING_SOFTWARE */
 629	SOCK_TIMESTAMPING_RAW_HARDWARE, /* %SOF_TIMESTAMPING_RAW_HARDWARE */
 630	SOCK_TIMESTAMPING_SYS_HARDWARE, /* %SOF_TIMESTAMPING_SYS_HARDWARE */
 631	SOCK_FASYNC, /* fasync() active */
 632	SOCK_RXQ_OVFL,
 633	SOCK_ZEROCOPY, /* buffers from userspace */
 634	SOCK_WIFI_STATUS, /* push wifi status to userspace */
 635	SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS.
 636		     * Will use last 4 bytes of packet sent from
 637		     * user-space instead.
 638		     */
 
 
 
 
 
 
 639};
 640
 
 
 641static inline void sock_copy_flags(struct sock *nsk, struct sock *osk)
 642{
 643	nsk->sk_flags = osk->sk_flags;
 644}
 645
 646static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
 647{
 648	__set_bit(flag, &sk->sk_flags);
 649}
 650
 651static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag)
 652{
 653	__clear_bit(flag, &sk->sk_flags);
 654}
 655
 
 
 
 
 
 
 
 
 
 656static inline bool sock_flag(const struct sock *sk, enum sock_flags flag)
 657{
 658	return test_bit(flag, &sk->sk_flags);
 659}
 660
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 661static inline void sk_acceptq_removed(struct sock *sk)
 662{
 663	sk->sk_ack_backlog--;
 664}
 665
 666static inline void sk_acceptq_added(struct sock *sk)
 667{
 668	sk->sk_ack_backlog++;
 669}
 670
 
 
 
 
 671static inline bool sk_acceptq_is_full(const struct sock *sk)
 672{
 673	return sk->sk_ack_backlog > sk->sk_max_ack_backlog;
 674}
 675
 676/*
 677 * Compute minimal free write space needed to queue new packets.
 678 */
 679static inline int sk_stream_min_wspace(const struct sock *sk)
 680{
 681	return sk->sk_wmem_queued >> 1;
 682}
 683
 684static inline int sk_stream_wspace(const struct sock *sk)
 685{
 686	return sk->sk_sndbuf - sk->sk_wmem_queued;
 687}
 688
 689extern void sk_stream_write_space(struct sock *sk);
 690
 691static inline bool sk_stream_memory_free(const struct sock *sk)
 692{
 693	return sk->sk_wmem_queued < sk->sk_sndbuf;
 694}
 695
 
 
 696/* OOB backlog add */
 697static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
 698{
 699	/* dont let skb dst not refcounted, we are going to leave rcu lock */
 700	skb_dst_force(skb);
 701
 702	if (!sk->sk_backlog.tail)
 703		sk->sk_backlog.head = skb;
 704	else
 705		sk->sk_backlog.tail->next = skb;
 706
 707	sk->sk_backlog.tail = skb;
 708	skb->next = NULL;
 709}
 710
 711/*
 712 * Take into account size of receive queue and backlog queue
 713 * Do not take into account this skb truesize,
 714 * to allow even a single big packet to come.
 715 */
 716static inline bool sk_rcvqueues_full(const struct sock *sk, const struct sk_buff *skb,
 717				     unsigned int limit)
 718{
 719	unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc);
 720
 721	return qsize > limit;
 722}
 723
 724/* The per-socket spinlock must be held here. */
 725static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb,
 726					      unsigned int limit)
 727{
 728	if (sk_rcvqueues_full(sk, skb, limit))
 729		return -ENOBUFS;
 730
 
 
 
 
 
 
 
 
 731	__sk_add_backlog(sk, skb);
 732	sk->sk_backlog.len += skb->truesize;
 733	return 0;
 734}
 735
 
 
 736static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
 737{
 
 
 
 738	return sk->sk_backlog_rcv(sk, skb);
 739}
 740
 741static inline void sock_rps_record_flow(const struct sock *sk)
 
 
 
 
 
 
 
 
 742{
 743#ifdef CONFIG_RPS
 744	struct rps_sock_flow_table *sock_flow_table;
 745
 746	rcu_read_lock();
 747	sock_flow_table = rcu_dereference(rps_sock_flow_table);
 748	rps_record_sock_flow(sock_flow_table, sk->sk_rxhash);
 749	rcu_read_unlock();
 750#endif
 751}
 752
 753static inline void sock_rps_reset_flow(const struct sock *sk)
 754{
 755#ifdef CONFIG_RPS
 756	struct rps_sock_flow_table *sock_flow_table;
 757
 758	rcu_read_lock();
 759	sock_flow_table = rcu_dereference(rps_sock_flow_table);
 760	rps_reset_sock_flow(sock_flow_table, sk->sk_rxhash);
 761	rcu_read_unlock();
 
 
 
 
 
 
 
 
 762#endif
 763}
 764
 765static inline void sock_rps_save_rxhash(struct sock *sk,
 766					const struct sk_buff *skb)
 767{
 768#ifdef CONFIG_RPS
 769	if (unlikely(sk->sk_rxhash != skb->rxhash)) {
 770		sock_rps_reset_flow(sk);
 771		sk->sk_rxhash = skb->rxhash;
 772	}
 773#endif
 774}
 775
 776static inline void sock_rps_reset_rxhash(struct sock *sk)
 777{
 778#ifdef CONFIG_RPS
 779	sock_rps_reset_flow(sk);
 780	sk->sk_rxhash = 0;
 781#endif
 782}
 783
 784#define sk_wait_event(__sk, __timeo, __condition)			\
 785	({	int __rc;						\
 786		release_sock(__sk);					\
 787		__rc = __condition;					\
 788		if (!__rc) {						\
 789			*(__timeo) = schedule_timeout(*(__timeo));	\
 
 
 790		}							\
 
 791		lock_sock(__sk);					\
 792		__rc = __condition;					\
 793		__rc;							\
 794	})
 795
 796extern int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
 797extern int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
 798extern void sk_stream_wait_close(struct sock *sk, long timeo_p);
 799extern int sk_stream_error(struct sock *sk, int flags, int err);
 800extern void sk_stream_kill_queues(struct sock *sk);
 
 
 801
 802extern int sk_wait_data(struct sock *sk, long *timeo);
 
 
 
 
 
 
 
 
 
 
 
 803
 804struct request_sock_ops;
 805struct timewait_sock_ops;
 806struct inet_hashinfo;
 807struct raw_hashinfo;
 
 808struct module;
 
 
 
 
 
 
 
 
 
 
 
 
 
 809
 810/* Networking protocol blocks we attach to sockets.
 811 * socket layer -> transport layer interface
 812 * transport -> network interface is defined by struct inet_proto
 813 */
 814struct proto {
 815	void			(*close)(struct sock *sk,
 816					long timeout);
 
 
 
 817	int			(*connect)(struct sock *sk,
 818					struct sockaddr *uaddr,
 819					int addr_len);
 820	int			(*disconnect)(struct sock *sk, int flags);
 821
 822	struct sock *		(*accept)(struct sock *sk, int flags, int *err);
 
 823
 824	int			(*ioctl)(struct sock *sk, int cmd,
 825					 unsigned long arg);
 826	int			(*init)(struct sock *sk);
 827	void			(*destroy)(struct sock *sk);
 828	void			(*shutdown)(struct sock *sk, int how);
 829	int			(*setsockopt)(struct sock *sk, int level,
 830					int optname, char __user *optval,
 831					unsigned int optlen);
 832	int			(*getsockopt)(struct sock *sk, int level,
 833					int optname, char __user *optval,
 834					int __user *option);
 
 835#ifdef CONFIG_COMPAT
 836	int			(*compat_setsockopt)(struct sock *sk,
 837					int level,
 838					int optname, char __user *optval,
 839					unsigned int optlen);
 840	int			(*compat_getsockopt)(struct sock *sk,
 841					int level,
 842					int optname, char __user *optval,
 843					int __user *option);
 844	int			(*compat_ioctl)(struct sock *sk,
 845					unsigned int cmd, unsigned long arg);
 846#endif
 847	int			(*sendmsg)(struct kiocb *iocb, struct sock *sk,
 848					   struct msghdr *msg, size_t len);
 849	int			(*recvmsg)(struct kiocb *iocb, struct sock *sk,
 850					   struct msghdr *msg,
 851					   size_t len, int noblock, int flags,
 852					   int *addr_len);
 853	int			(*sendpage)(struct sock *sk, struct page *page,
 854					int offset, size_t size, int flags);
 855	int			(*bind)(struct sock *sk,
 856					struct sockaddr *uaddr, int addr_len);
 
 
 857
 858	int			(*backlog_rcv) (struct sock *sk,
 859						struct sk_buff *skb);
 
 
 
 
 860
 861	/* Keeping track of sk's, looking them up, and port selection methods. */
 862	void			(*hash)(struct sock *sk);
 863	void			(*unhash)(struct sock *sk);
 864	void			(*rehash)(struct sock *sk);
 865	int			(*get_port)(struct sock *sk, unsigned short snum);
 866	void			(*clear_sk)(struct sock *sk, int size);
 
 
 
 
 867
 868	/* Keeping track of sockets in use */
 869#ifdef CONFIG_PROC_FS
 870	unsigned int		inuse_idx;
 871#endif
 872
 
 
 873	/* Memory pressure */
 874	void			(*enter_memory_pressure)(struct sock *sk);
 
 875	atomic_long_t		*memory_allocated;	/* Current allocated memory. */
 876	struct percpu_counter	*sockets_allocated;	/* Current number of sockets. */
 877	/*
 878	 * Pressure flag: try to collapse.
 879	 * Technical note: it is used by multiple contexts non atomically.
 880	 * All the __sk_mem_schedule() is of this nature: accounting
 881	 * is strict, actions are advisory and have some latency.
 882	 */
 883	int			*memory_pressure;
 884	long			*sysctl_mem;
 
 885	int			*sysctl_wmem;
 886	int			*sysctl_rmem;
 
 
 
 887	int			max_header;
 888	bool			no_autobind;
 889
 890	struct kmem_cache	*slab;
 891	unsigned int		obj_size;
 892	int			slab_flags;
 
 
 893
 894	struct percpu_counter	*orphan_count;
 895
 896	struct request_sock_ops	*rsk_prot;
 897	struct timewait_sock_ops *twsk_prot;
 898
 899	union {
 900		struct inet_hashinfo	*hashinfo;
 901		struct udp_table	*udp_table;
 902		struct raw_hashinfo	*raw_hash;
 
 903	} h;
 904
 905	struct module		*owner;
 906
 907	char			name[32];
 908
 909	struct list_head	node;
 910#ifdef SOCK_REFCNT_DEBUG
 911	atomic_t		socks;
 912#endif
 913#ifdef CONFIG_CGROUP_MEM_RES_CTLR_KMEM
 914	/*
 915	 * cgroup specific init/deinit functions. Called once for all
 916	 * protocols that implement it, from cgroups populate function.
 917	 * This function has to setup any files the protocol want to
 918	 * appear in the kmem cgroup filesystem.
 919	 */
 920	int			(*init_cgroup)(struct mem_cgroup *memcg,
 921					       struct cgroup_subsys *ss);
 922	void			(*destroy_cgroup)(struct mem_cgroup *memcg);
 923	struct cg_proto		*(*proto_cgroup)(struct mem_cgroup *memcg);
 924#endif
 925};
 926
 927/*
 928 * Bits in struct cg_proto.flags
 929 */
 930enum cg_proto_flags {
 931	/* Currently active and new sockets should be assigned to cgroups */
 932	MEMCG_SOCK_ACTIVE,
 933	/* It was ever activated; we must disarm static keys on destruction */
 934	MEMCG_SOCK_ACTIVATED,
 935};
 936
 937struct cg_proto {
 938	void			(*enter_memory_pressure)(struct sock *sk);
 939	struct res_counter	*memory_allocated;	/* Current allocated memory. */
 940	struct percpu_counter	*sockets_allocated;	/* Current number of sockets. */
 941	int			*memory_pressure;
 942	long			*sysctl_mem;
 943	unsigned long		flags;
 944	/*
 945	 * memcg field is used to find which memcg we belong directly
 946	 * Each memcg struct can hold more than one cg_proto, so container_of
 947	 * won't really cut.
 948	 *
 949	 * The elegant solution would be having an inverse function to
 950	 * proto_cgroup in struct proto, but that means polluting the structure
 951	 * for everybody, instead of just for memcg users.
 952	 */
 953	struct mem_cgroup	*memcg;
 954};
 955
 956extern int proto_register(struct proto *prot, int alloc_slab);
 957extern void proto_unregister(struct proto *prot);
 958
 959static inline bool memcg_proto_active(struct cg_proto *cg_proto)
 960{
 961	return test_bit(MEMCG_SOCK_ACTIVE, &cg_proto->flags);
 962}
 963
 964static inline bool memcg_proto_activated(struct cg_proto *cg_proto)
 965{
 966	return test_bit(MEMCG_SOCK_ACTIVATED, &cg_proto->flags);
 967}
 968
 969#ifdef SOCK_REFCNT_DEBUG
 970static inline void sk_refcnt_debug_inc(struct sock *sk)
 971{
 972	atomic_inc(&sk->sk_prot->socks);
 973}
 974
 975static inline void sk_refcnt_debug_dec(struct sock *sk)
 976{
 977	atomic_dec(&sk->sk_prot->socks);
 978	printk(KERN_DEBUG "%s socket %p released, %d are still alive\n",
 979	       sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks));
 980}
 981
 982inline void sk_refcnt_debug_release(const struct sock *sk)
 983{
 984	if (atomic_read(&sk->sk_refcnt) != 1)
 985		printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n",
 986		       sk->sk_prot->name, sk, atomic_read(&sk->sk_refcnt));
 987}
 988#else /* SOCK_REFCNT_DEBUG */
 989#define sk_refcnt_debug_inc(sk) do { } while (0)
 990#define sk_refcnt_debug_dec(sk) do { } while (0)
 991#define sk_refcnt_debug_release(sk) do { } while (0)
 992#endif /* SOCK_REFCNT_DEBUG */
 993
 994#if defined(CONFIG_CGROUP_MEM_RES_CTLR_KMEM) && defined(CONFIG_NET)
 995extern struct static_key memcg_socket_limit_enabled;
 996static inline struct cg_proto *parent_cg_proto(struct proto *proto,
 997					       struct cg_proto *cg_proto)
 998{
 999	return proto->proto_cgroup(parent_mem_cgroup(cg_proto->memcg));
1000}
1001#define mem_cgroup_sockets_enabled static_key_false(&memcg_socket_limit_enabled)
 
 
 
 
 
1002#else
1003#define mem_cgroup_sockets_enabled 0
1004static inline struct cg_proto *parent_cg_proto(struct proto *proto,
1005					       struct cg_proto *cg_proto)
1006{
1007	return NULL;
1008}
1009#endif
1010
1011
1012static inline bool sk_has_memory_pressure(const struct sock *sk)
1013{
1014	return sk->sk_prot->memory_pressure != NULL;
1015}
1016
1017static inline bool sk_under_memory_pressure(const struct sock *sk)
1018{
1019	if (!sk->sk_prot->memory_pressure)
1020		return false;
1021
1022	if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1023		return !!*sk->sk_cgrp->memory_pressure;
1024
1025	return !!*sk->sk_prot->memory_pressure;
1026}
1027
1028static inline void sk_leave_memory_pressure(struct sock *sk)
1029{
1030	int *memory_pressure = sk->sk_prot->memory_pressure;
1031
1032	if (!memory_pressure)
1033		return;
1034
1035	if (*memory_pressure)
1036		*memory_pressure = 0;
1037
1038	if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1039		struct cg_proto *cg_proto = sk->sk_cgrp;
1040		struct proto *prot = sk->sk_prot;
1041
1042		for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto))
1043			if (*cg_proto->memory_pressure)
1044				*cg_proto->memory_pressure = 0;
1045	}
1046
1047}
1048
1049static inline void sk_enter_memory_pressure(struct sock *sk)
 
1050{
1051	if (!sk->sk_prot->enter_memory_pressure)
1052		return;
1053
1054	if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1055		struct cg_proto *cg_proto = sk->sk_cgrp;
1056		struct proto *prot = sk->sk_prot;
1057
1058		for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto))
1059			cg_proto->enter_memory_pressure(sk);
1060	}
1061
1062	sk->sk_prot->enter_memory_pressure(sk);
1063}
1064
1065static inline long sk_prot_mem_limits(const struct sock *sk, int index)
1066{
1067	long *prot = sk->sk_prot->sysctl_mem;
1068	if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1069		prot = sk->sk_cgrp->sysctl_mem;
1070	return prot[index];
1071}
1072
1073static inline void memcg_memory_allocated_add(struct cg_proto *prot,
1074					      unsigned long amt,
1075					      int *parent_status)
1076{
1077	struct res_counter *fail;
1078	int ret;
1079
1080	ret = res_counter_charge_nofail(prot->memory_allocated,
1081					amt << PAGE_SHIFT, &fail);
1082	if (ret < 0)
1083		*parent_status = OVER_LIMIT;
1084}
1085
1086static inline void memcg_memory_allocated_sub(struct cg_proto *prot,
1087					      unsigned long amt)
1088{
1089	res_counter_uncharge(prot->memory_allocated, amt << PAGE_SHIFT);
1090}
1091
1092static inline u64 memcg_memory_allocated_read(struct cg_proto *prot)
1093{
1094	u64 ret;
1095	ret = res_counter_read_u64(prot->memory_allocated, RES_USAGE);
1096	return ret >> PAGE_SHIFT;
1097}
1098
1099static inline long
1100sk_memory_allocated(const struct sock *sk)
1101{
1102	struct proto *prot = sk->sk_prot;
1103	if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1104		return memcg_memory_allocated_read(sk->sk_cgrp);
1105
1106	return atomic_long_read(prot->memory_allocated);
1107}
1108
1109static inline long
1110sk_memory_allocated_add(struct sock *sk, int amt, int *parent_status)
1111{
1112	struct proto *prot = sk->sk_prot;
1113
1114	if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1115		memcg_memory_allocated_add(sk->sk_cgrp, amt, parent_status);
1116		/* update the root cgroup regardless */
1117		atomic_long_add_return(amt, prot->memory_allocated);
1118		return memcg_memory_allocated_read(sk->sk_cgrp);
1119	}
1120
1121	return atomic_long_add_return(amt, prot->memory_allocated);
1122}
1123
1124static inline void
1125sk_memory_allocated_sub(struct sock *sk, int amt)
1126{
1127	struct proto *prot = sk->sk_prot;
1128
1129	if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1130		memcg_memory_allocated_sub(sk->sk_cgrp, amt);
1131
1132	atomic_long_sub(amt, prot->memory_allocated);
1133}
1134
1135static inline void sk_sockets_allocated_dec(struct sock *sk)
1136{
1137	struct proto *prot = sk->sk_prot;
1138
1139	if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1140		struct cg_proto *cg_proto = sk->sk_cgrp;
1141
1142		for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto))
1143			percpu_counter_dec(cg_proto->sockets_allocated);
1144	}
1145
1146	percpu_counter_dec(prot->sockets_allocated);
1147}
1148
1149static inline void sk_sockets_allocated_inc(struct sock *sk)
1150{
1151	struct proto *prot = sk->sk_prot;
1152
1153	if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1154		struct cg_proto *cg_proto = sk->sk_cgrp;
1155
1156		for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto))
1157			percpu_counter_inc(cg_proto->sockets_allocated);
1158	}
1159
1160	percpu_counter_inc(prot->sockets_allocated);
1161}
1162
1163static inline int
1164sk_sockets_allocated_read_positive(struct sock *sk)
1165{
1166	struct proto *prot = sk->sk_prot;
1167
1168	if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1169		return percpu_counter_read_positive(sk->sk_cgrp->sockets_allocated);
1170
1171	return percpu_counter_read_positive(prot->sockets_allocated);
1172}
1173
1174static inline int
1175proto_sockets_allocated_sum_positive(struct proto *prot)
1176{
1177	return percpu_counter_sum_positive(prot->sockets_allocated);
1178}
1179
1180static inline long
1181proto_memory_allocated(struct proto *prot)
1182{
1183	return atomic_long_read(prot->memory_allocated);
1184}
1185
1186static inline bool
1187proto_memory_pressure(struct proto *prot)
1188{
1189	if (!prot->memory_pressure)
1190		return false;
1191	return !!*prot->memory_pressure;
1192}
1193
1194
1195#ifdef CONFIG_PROC_FS
1196/* Called with local bh disabled */
1197extern void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc);
1198extern int sock_prot_inuse_get(struct net *net, struct proto *proto);
 
1199#else
1200static inline void sock_prot_inuse_add(struct net *net, struct proto *prot,
1201		int inc)
1202{
1203}
1204#endif
1205
1206
1207/* With per-bucket locks this operation is not-atomic, so that
1208 * this version is not worse.
1209 */
1210static inline void __sk_prot_rehash(struct sock *sk)
1211{
1212	sk->sk_prot->unhash(sk);
1213	sk->sk_prot->hash(sk);
1214}
1215
1216void sk_prot_clear_portaddr_nulls(struct sock *sk, int size);
1217
1218/* About 10 seconds */
1219#define SOCK_DESTROY_TIME (10*HZ)
1220
1221/* Sockets 0-1023 can't be bound to unless you are superuser */
1222#define PROT_SOCK	1024
1223
1224#define SHUTDOWN_MASK	3
1225#define RCV_SHUTDOWN	1
1226#define SEND_SHUTDOWN	2
1227
1228#define SOCK_SNDBUF_LOCK	1
1229#define SOCK_RCVBUF_LOCK	2
1230#define SOCK_BINDADDR_LOCK	4
1231#define SOCK_BINDPORT_LOCK	8
1232
1233/* sock_iocb: used to kick off async processing of socket ios */
1234struct sock_iocb {
1235	struct list_head	list;
1236
1237	int			flags;
1238	int			size;
1239	struct socket		*sock;
1240	struct sock		*sk;
1241	struct scm_cookie	*scm;
1242	struct msghdr		*msg, async_msg;
1243	struct kiocb		*kiocb;
1244};
1245
1246static inline struct sock_iocb *kiocb_to_siocb(struct kiocb *iocb)
1247{
1248	return (struct sock_iocb *)iocb->private;
1249}
1250
1251static inline struct kiocb *siocb_to_kiocb(struct sock_iocb *si)
1252{
1253	return si->kiocb;
1254}
1255
1256struct socket_alloc {
1257	struct socket socket;
1258	struct inode vfs_inode;
1259};
1260
1261static inline struct socket *SOCKET_I(struct inode *inode)
1262{
1263	return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
1264}
1265
1266static inline struct inode *SOCK_INODE(struct socket *socket)
1267{
1268	return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
1269}
1270
1271/*
1272 * Functions for memory accounting
1273 */
1274extern int __sk_mem_schedule(struct sock *sk, int size, int kind);
1275extern void __sk_mem_reclaim(struct sock *sk);
 
 
1276
1277#define SK_MEM_QUANTUM ((int)PAGE_SIZE)
 
 
 
1278#define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM)
1279#define SK_MEM_SEND	0
1280#define SK_MEM_RECV	1
1281
 
 
 
 
 
 
 
 
 
 
 
 
 
1282static inline int sk_mem_pages(int amt)
1283{
1284	return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT;
1285}
1286
1287static inline bool sk_has_account(struct sock *sk)
1288{
1289	/* return true if protocol supports memory accounting */
1290	return !!sk->sk_prot->memory_allocated;
1291}
1292
1293static inline bool sk_wmem_schedule(struct sock *sk, int size)
1294{
1295	if (!sk_has_account(sk))
1296		return true;
1297	return size <= sk->sk_forward_alloc ||
1298		__sk_mem_schedule(sk, size, SK_MEM_SEND);
1299}
1300
1301static inline bool sk_rmem_schedule(struct sock *sk, int size)
 
1302{
1303	if (!sk_has_account(sk))
1304		return true;
1305	return size <= sk->sk_forward_alloc ||
1306		__sk_mem_schedule(sk, size, SK_MEM_RECV);
 
1307}
1308
1309static inline void sk_mem_reclaim(struct sock *sk)
1310{
1311	if (!sk_has_account(sk))
1312		return;
1313	if (sk->sk_forward_alloc >= SK_MEM_QUANTUM)
1314		__sk_mem_reclaim(sk);
1315}
1316
1317static inline void sk_mem_reclaim_partial(struct sock *sk)
1318{
1319	if (!sk_has_account(sk))
1320		return;
1321	if (sk->sk_forward_alloc > SK_MEM_QUANTUM)
1322		__sk_mem_reclaim(sk);
1323}
1324
1325static inline void sk_mem_charge(struct sock *sk, int size)
1326{
1327	if (!sk_has_account(sk))
1328		return;
1329	sk->sk_forward_alloc -= size;
1330}
1331
1332static inline void sk_mem_uncharge(struct sock *sk, int size)
1333{
1334	if (!sk_has_account(sk))
1335		return;
1336	sk->sk_forward_alloc += size;
 
 
 
 
 
 
 
 
 
 
1337}
1338
 
1339static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb)
1340{
1341	sock_set_flag(sk, SOCK_QUEUE_SHRUNK);
1342	sk->sk_wmem_queued -= skb->truesize;
1343	sk_mem_uncharge(sk, skb->truesize);
 
 
 
 
 
 
 
1344	__kfree_skb(skb);
1345}
1346
1347/* Used by processes to "lock" a socket state, so that
1348 * interrupts and bottom half handlers won't change it
1349 * from under us. It essentially blocks any incoming
1350 * packets, so that we won't get any new data or any
1351 * packets that change the state of the socket.
1352 *
1353 * While locked, BH processing will add new packets to
1354 * the backlog queue.  This queue is processed by the
1355 * owner of the socket lock right before it is released.
1356 *
1357 * Since ~2.3.5 it is also exclusive sleep lock serializing
1358 * accesses from user process context.
1359 */
1360#define sock_owned_by_user(sk)	((sk)->sk_lock.owned)
1361
1362/*
1363 * Macro so as to not evaluate some arguments when
1364 * lockdep is not enabled.
1365 *
1366 * Mark both the sk_lock and the sk_lock.slock as a
1367 * per-address-family lock class.
1368 */
1369#define sock_lock_init_class_and_name(sk, sname, skey, name, key)	\
1370do {									\
1371	sk->sk_lock.owned = 0;						\
1372	init_waitqueue_head(&sk->sk_lock.wq);				\
1373	spin_lock_init(&(sk)->sk_lock.slock);				\
1374	debug_check_no_locks_freed((void *)&(sk)->sk_lock,		\
1375			sizeof((sk)->sk_lock));				\
1376	lockdep_set_class_and_name(&(sk)->sk_lock.slock,		\
1377				(skey), (sname));				\
1378	lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0);	\
1379} while (0)
1380
1381extern void lock_sock_nested(struct sock *sk, int subclass);
 
 
 
 
 
 
1382
1383static inline void lock_sock(struct sock *sk)
1384{
1385	lock_sock_nested(sk, 0);
1386}
1387
1388extern void release_sock(struct sock *sk);
 
 
1389
1390/* BH context may only use the following locking interface. */
1391#define bh_lock_sock(__sk)	spin_lock(&((__sk)->sk_lock.slock))
1392#define bh_lock_sock_nested(__sk) \
1393				spin_lock_nested(&((__sk)->sk_lock.slock), \
1394				SINGLE_DEPTH_NESTING)
1395#define bh_unlock_sock(__sk)	spin_unlock(&((__sk)->sk_lock.slock))
1396
1397extern bool lock_sock_fast(struct sock *sk);
 
1398/**
1399 * unlock_sock_fast - complement of lock_sock_fast
1400 * @sk: socket
1401 * @slow: slow mode
1402 *
1403 * fast unlock socket for user context.
1404 * If slow mode is on, we call regular release_sock()
1405 */
1406static inline void unlock_sock_fast(struct sock *sk, bool slow)
 
1407{
1408	if (slow)
1409		release_sock(sk);
1410	else
 
1411		spin_unlock_bh(&sk->sk_lock.slock);
 
1412}
1413
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1414
1415extern struct sock		*sk_alloc(struct net *net, int family,
1416					  gfp_t priority,
1417					  struct proto *prot);
1418extern void			sk_free(struct sock *sk);
1419extern void			sk_release_kernel(struct sock *sk);
1420extern struct sock		*sk_clone_lock(const struct sock *sk,
1421					       const gfp_t priority);
1422
1423extern struct sk_buff		*sock_wmalloc(struct sock *sk,
1424					      unsigned long size, int force,
1425					      gfp_t priority);
1426extern struct sk_buff		*sock_rmalloc(struct sock *sk,
1427					      unsigned long size, int force,
1428					      gfp_t priority);
1429extern void			sock_wfree(struct sk_buff *skb);
1430extern void			sock_rfree(struct sk_buff *skb);
1431
1432extern int			sock_setsockopt(struct socket *sock, int level,
1433						int op, char __user *optval,
1434						unsigned int optlen);
1435
1436extern int			sock_getsockopt(struct socket *sock, int level,
1437						int op, char __user *optval,
1438						int __user *optlen);
1439extern struct sk_buff		*sock_alloc_send_skb(struct sock *sk,
1440						     unsigned long size,
1441						     int noblock,
1442						     int *errcode);
1443extern struct sk_buff		*sock_alloc_send_pskb(struct sock *sk,
1444						      unsigned long header_len,
1445						      unsigned long data_len,
1446						      int noblock,
1447						      int *errcode);
1448extern void *sock_kmalloc(struct sock *sk, int size,
1449			  gfp_t priority);
1450extern void sock_kfree_s(struct sock *sk, void *mem, int size);
1451extern void sk_send_sigurg(struct sock *sk);
1452
1453#ifdef CONFIG_CGROUPS
1454extern void sock_update_classid(struct sock *sk);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1455#else
1456static inline void sock_update_classid(struct sock *sk)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1457{
 
1458}
1459#endif
 
 
 
 
1460
1461/*
1462 * Functions to fill in entries in struct proto_ops when a protocol
1463 * does not implement a particular function.
1464 */
1465extern int                      sock_no_bind(struct socket *,
1466					     struct sockaddr *, int);
1467extern int                      sock_no_connect(struct socket *,
1468						struct sockaddr *, int, int);
1469extern int                      sock_no_socketpair(struct socket *,
1470						   struct socket *);
1471extern int                      sock_no_accept(struct socket *,
1472					       struct socket *, int);
1473extern int                      sock_no_getname(struct socket *,
1474						struct sockaddr *, int *, int);
1475extern unsigned int             sock_no_poll(struct file *, struct socket *,
1476					     struct poll_table_struct *);
1477extern int                      sock_no_ioctl(struct socket *, unsigned int,
1478					      unsigned long);
1479extern int			sock_no_listen(struct socket *, int);
1480extern int                      sock_no_shutdown(struct socket *, int);
1481extern int			sock_no_getsockopt(struct socket *, int , int,
1482						   char __user *, int __user *);
1483extern int			sock_no_setsockopt(struct socket *, int, int,
1484						   char __user *, unsigned int);
1485extern int                      sock_no_sendmsg(struct kiocb *, struct socket *,
1486						struct msghdr *, size_t);
1487extern int                      sock_no_recvmsg(struct kiocb *, struct socket *,
1488						struct msghdr *, size_t, int);
1489extern int			sock_no_mmap(struct file *file,
1490					     struct socket *sock,
1491					     struct vm_area_struct *vma);
1492extern ssize_t			sock_no_sendpage(struct socket *sock,
1493						struct page *page,
1494						int offset, size_t size,
1495						int flags);
1496
1497/*
1498 * Functions to fill in entries in struct proto_ops when a protocol
1499 * uses the inet style.
1500 */
1501extern int sock_common_getsockopt(struct socket *sock, int level, int optname,
1502				  char __user *optval, int __user *optlen);
1503extern int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock,
1504			       struct msghdr *msg, size_t size, int flags);
1505extern int sock_common_setsockopt(struct socket *sock, int level, int optname,
1506				  char __user *optval, unsigned int optlen);
1507extern int compat_sock_common_getsockopt(struct socket *sock, int level,
1508		int optname, char __user *optval, int __user *optlen);
1509extern int compat_sock_common_setsockopt(struct socket *sock, int level,
1510		int optname, char __user *optval, unsigned int optlen);
1511
1512extern void sk_common_release(struct sock *sk);
1513
1514/*
1515 *	Default socket callbacks and setup code
1516 */
1517
1518/* Initialise core socket variables */
1519extern void sock_init_data(struct socket *sock, struct sock *sk);
1520
1521extern void sk_filter_release_rcu(struct rcu_head *rcu);
1522
1523/**
1524 *	sk_filter_release - release a socket filter
1525 *	@fp: filter to remove
1526 *
1527 *	Remove a filter from a socket and release its resources.
1528 */
1529
1530static inline void sk_filter_release(struct sk_filter *fp)
1531{
1532	if (atomic_dec_and_test(&fp->refcnt))
1533		call_rcu(&fp->rcu, sk_filter_release_rcu);
1534}
1535
1536static inline void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp)
1537{
1538	unsigned int size = sk_filter_len(fp);
1539
1540	atomic_sub(size, &sk->sk_omem_alloc);
1541	sk_filter_release(fp);
1542}
1543
1544static inline void sk_filter_charge(struct sock *sk, struct sk_filter *fp)
1545{
1546	atomic_inc(&fp->refcnt);
1547	atomic_add(sk_filter_len(fp), &sk->sk_omem_alloc);
1548}
1549
1550/*
1551 * Socket reference counting postulates.
1552 *
1553 * * Each user of socket SHOULD hold a reference count.
1554 * * Each access point to socket (an hash table bucket, reference from a list,
1555 *   running timer, skb in flight MUST hold a reference count.
1556 * * When reference count hits 0, it means it will never increase back.
1557 * * When reference count hits 0, it means that no references from
1558 *   outside exist to this socket and current process on current CPU
1559 *   is last user and may/should destroy this socket.
1560 * * sk_free is called from any context: process, BH, IRQ. When
1561 *   it is called, socket has no references from outside -> sk_free
1562 *   may release descendant resources allocated by the socket, but
1563 *   to the time when it is called, socket is NOT referenced by any
1564 *   hash tables, lists etc.
1565 * * Packets, delivered from outside (from network or from another process)
1566 *   and enqueued on receive/error queues SHOULD NOT grab reference count,
1567 *   when they sit in queue. Otherwise, packets will leak to hole, when
1568 *   socket is looked up by one cpu and unhasing is made by another CPU.
1569 *   It is true for udp/raw, netlink (leak to receive and error queues), tcp
1570 *   (leak to backlog). Packet socket does all the processing inside
1571 *   BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
1572 *   use separate SMP lock, so that they are prone too.
1573 */
1574
1575/* Ungrab socket and destroy it, if it was the last reference. */
1576static inline void sock_put(struct sock *sk)
1577{
1578	if (atomic_dec_and_test(&sk->sk_refcnt))
1579		sk_free(sk);
1580}
 
 
 
 
1581
1582extern int sk_receive_skb(struct sock *sk, struct sk_buff *skb,
1583			  const int nested);
 
 
 
 
 
1584
1585static inline void sk_tx_queue_set(struct sock *sk, int tx_queue)
1586{
 
 
 
1587	sk->sk_tx_queue_mapping = tx_queue;
1588}
1589
 
 
1590static inline void sk_tx_queue_clear(struct sock *sk)
1591{
1592	sk->sk_tx_queue_mapping = -1;
1593}
1594
1595static inline int sk_tx_queue_get(const struct sock *sk)
1596{
1597	return sk ? sk->sk_tx_queue_mapping : -1;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1598}
1599
1600static inline void sk_set_socket(struct sock *sk, struct socket *sock)
1601{
1602	sk_tx_queue_clear(sk);
1603	sk->sk_socket = sock;
1604}
1605
1606static inline wait_queue_head_t *sk_sleep(struct sock *sk)
1607{
1608	BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0);
1609	return &rcu_dereference_raw(sk->sk_wq)->wait;
1610}
1611/* Detach socket from process context.
1612 * Announce socket dead, detach it from wait queue and inode.
1613 * Note that parent inode held reference count on this struct sock,
1614 * we do not release it in this function, because protocol
1615 * probably wants some additional cleanups or even continuing
1616 * to work with this socket (TCP).
1617 */
1618static inline void sock_orphan(struct sock *sk)
1619{
1620	write_lock_bh(&sk->sk_callback_lock);
1621	sock_set_flag(sk, SOCK_DEAD);
1622	sk_set_socket(sk, NULL);
1623	sk->sk_wq  = NULL;
1624	write_unlock_bh(&sk->sk_callback_lock);
1625}
1626
1627static inline void sock_graft(struct sock *sk, struct socket *parent)
1628{
 
1629	write_lock_bh(&sk->sk_callback_lock);
1630	sk->sk_wq = parent->wq;
1631	parent->sk = sk;
1632	sk_set_socket(sk, parent);
 
1633	security_sock_graft(sk, parent);
1634	write_unlock_bh(&sk->sk_callback_lock);
1635}
1636
1637extern int sock_i_uid(struct sock *sk);
1638extern unsigned long sock_i_ino(struct sock *sk);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1639
1640static inline struct dst_entry *
1641__sk_dst_get(struct sock *sk)
1642{
1643	return rcu_dereference_check(sk->sk_dst_cache, sock_owned_by_user(sk) ||
1644						       lockdep_is_held(&sk->sk_lock.slock));
1645}
1646
1647static inline struct dst_entry *
1648sk_dst_get(struct sock *sk)
1649{
1650	struct dst_entry *dst;
1651
1652	rcu_read_lock();
1653	dst = rcu_dereference(sk->sk_dst_cache);
1654	if (dst)
1655		dst_hold(dst);
1656	rcu_read_unlock();
1657	return dst;
1658}
1659
1660extern void sk_reset_txq(struct sock *sk);
1661
1662static inline void dst_negative_advice(struct sock *sk)
1663{
1664	struct dst_entry *ndst, *dst = __sk_dst_get(sk);
1665
1666	if (dst && dst->ops->negative_advice) {
1667		ndst = dst->ops->negative_advice(dst);
1668
1669		if (ndst != dst) {
1670			rcu_assign_pointer(sk->sk_dst_cache, ndst);
1671			sk_reset_txq(sk);
 
1672		}
1673	}
1674}
1675
 
 
 
 
 
 
1676static inline void
1677__sk_dst_set(struct sock *sk, struct dst_entry *dst)
1678{
1679	struct dst_entry *old_dst;
1680
1681	sk_tx_queue_clear(sk);
1682	/*
1683	 * This can be called while sk is owned by the caller only,
1684	 * with no state that can be checked in a rcu_dereference_check() cond
1685	 */
1686	old_dst = rcu_dereference_raw(sk->sk_dst_cache);
1687	rcu_assign_pointer(sk->sk_dst_cache, dst);
1688	dst_release(old_dst);
1689}
1690
1691static inline void
1692sk_dst_set(struct sock *sk, struct dst_entry *dst)
1693{
1694	spin_lock(&sk->sk_dst_lock);
1695	__sk_dst_set(sk, dst);
1696	spin_unlock(&sk->sk_dst_lock);
 
 
 
1697}
1698
1699static inline void
1700__sk_dst_reset(struct sock *sk)
1701{
1702	__sk_dst_set(sk, NULL);
1703}
1704
1705static inline void
1706sk_dst_reset(struct sock *sk)
1707{
1708	spin_lock(&sk->sk_dst_lock);
1709	__sk_dst_reset(sk);
1710	spin_unlock(&sk->sk_dst_lock);
 
 
 
 
 
 
 
 
1711}
1712
1713extern struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
 
 
 
 
 
 
 
 
 
 
 
 
1714
1715extern struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
1716
1717static inline bool sk_can_gso(const struct sock *sk)
1718{
1719	return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type);
1720}
1721
1722extern void sk_setup_caps(struct sock *sk, struct dst_entry *dst);
1723
1724static inline void sk_nocaps_add(struct sock *sk, netdev_features_t flags)
1725{
1726	sk->sk_route_nocaps |= flags;
1727	sk->sk_route_caps &= ~flags;
1728}
1729
1730static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
1731					   char __user *from, char *to,
1732					   int copy, int offset)
1733{
1734	if (skb->ip_summed == CHECKSUM_NONE) {
1735		int err = 0;
1736		__wsum csum = csum_and_copy_from_user(from, to, copy, 0, &err);
1737		if (err)
1738			return err;
1739		skb->csum = csum_block_add(skb->csum, csum, offset);
1740	} else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
1741		if (!access_ok(VERIFY_READ, from, copy) ||
1742		    __copy_from_user_nocache(to, from, copy))
1743			return -EFAULT;
1744	} else if (copy_from_user(to, from, copy))
1745		return -EFAULT;
1746
1747	return 0;
1748}
1749
1750static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
1751				       char __user *from, int copy)
1752{
1753	int err, offset = skb->len;
1754
1755	err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy),
1756				       copy, offset);
1757	if (err)
1758		__skb_trim(skb, offset);
1759
1760	return err;
1761}
1762
1763static inline int skb_copy_to_page_nocache(struct sock *sk, char __user *from,
1764					   struct sk_buff *skb,
1765					   struct page *page,
1766					   int off, int copy)
1767{
1768	int err;
1769
1770	err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off,
1771				       copy, skb->len);
1772	if (err)
1773		return err;
1774
1775	skb->len	     += copy;
1776	skb->data_len	     += copy;
1777	skb->truesize	     += copy;
1778	sk->sk_wmem_queued   += copy;
1779	sk_mem_charge(sk, copy);
1780	return 0;
1781}
1782
1783static inline int skb_copy_to_page(struct sock *sk, char __user *from,
1784				   struct sk_buff *skb, struct page *page,
1785				   int off, int copy)
1786{
1787	if (skb->ip_summed == CHECKSUM_NONE) {
1788		int err = 0;
1789		__wsum csum = csum_and_copy_from_user(from,
1790						     page_address(page) + off,
1791							    copy, 0, &err);
1792		if (err)
1793			return err;
1794		skb->csum = csum_block_add(skb->csum, csum, skb->len);
1795	} else if (copy_from_user(page_address(page) + off, from, copy))
1796		return -EFAULT;
1797
1798	skb->len	     += copy;
1799	skb->data_len	     += copy;
1800	skb->truesize	     += copy;
1801	sk->sk_wmem_queued   += copy;
1802	sk_mem_charge(sk, copy);
1803	return 0;
1804}
1805
1806/**
1807 * sk_wmem_alloc_get - returns write allocations
1808 * @sk: socket
1809 *
1810 * Returns sk_wmem_alloc minus initial offset of one
1811 */
1812static inline int sk_wmem_alloc_get(const struct sock *sk)
1813{
1814	return atomic_read(&sk->sk_wmem_alloc) - 1;
1815}
1816
1817/**
1818 * sk_rmem_alloc_get - returns read allocations
1819 * @sk: socket
1820 *
1821 * Returns sk_rmem_alloc
1822 */
1823static inline int sk_rmem_alloc_get(const struct sock *sk)
1824{
1825	return atomic_read(&sk->sk_rmem_alloc);
1826}
1827
1828/**
1829 * sk_has_allocations - check if allocations are outstanding
1830 * @sk: socket
1831 *
1832 * Returns true if socket has write or read allocations
1833 */
1834static inline bool sk_has_allocations(const struct sock *sk)
1835{
1836	return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk);
1837}
1838
1839/**
1840 * wq_has_sleeper - check if there are any waiting processes
1841 * @wq: struct socket_wq
1842 *
1843 * Returns true if socket_wq has waiting processes
1844 *
1845 * The purpose of the wq_has_sleeper and sock_poll_wait is to wrap the memory
1846 * barrier call. They were added due to the race found within the tcp code.
1847 *
1848 * Consider following tcp code paths:
1849 *
1850 * CPU1                  CPU2
1851 *
1852 * sys_select            receive packet
 
1853 *   ...                 ...
1854 *   __add_wait_queue    update tp->rcv_nxt
1855 *   ...                 ...
1856 *   tp->rcv_nxt check   sock_def_readable
1857 *   ...                 {
1858 *   schedule               rcu_read_lock();
1859 *                          wq = rcu_dereference(sk->sk_wq);
1860 *                          if (wq && waitqueue_active(&wq->wait))
1861 *                              wake_up_interruptible(&wq->wait)
1862 *                          ...
1863 *                       }
1864 *
1865 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
1866 * in its cache, and so does the tp->rcv_nxt update on CPU2 side.  The CPU1
1867 * could then endup calling schedule and sleep forever if there are no more
1868 * data on the socket.
1869 *
1870 */
1871static inline bool wq_has_sleeper(struct socket_wq *wq)
1872{
1873	/* We need to be sure we are in sync with the
1874	 * add_wait_queue modifications to the wait queue.
1875	 *
1876	 * This memory barrier is paired in the sock_poll_wait.
1877	 */
1878	smp_mb();
1879	return wq && waitqueue_active(&wq->wait);
1880}
1881
1882/**
1883 * sock_poll_wait - place memory barrier behind the poll_wait call.
1884 * @filp:           file
1885 * @wait_address:   socket wait queue
1886 * @p:              poll_table
1887 *
1888 * See the comments in the wq_has_sleeper function.
1889 */
1890static inline void sock_poll_wait(struct file *filp,
1891		wait_queue_head_t *wait_address, poll_table *p)
1892{
1893	if (!poll_does_not_wait(p) && wait_address) {
1894		poll_wait(filp, wait_address, p);
1895		/* We need to be sure we are in sync with the
1896		 * socket flags modification.
1897		 *
1898		 * This memory barrier is paired in the wq_has_sleeper.
1899		 */
1900		smp_mb();
1901	}
1902}
1903
 
 
 
 
 
 
 
 
 
 
 
 
 
1904/*
1905 *	Queue a received datagram if it will fit. Stream and sequenced
1906 *	protocols can't normally use this as they need to fit buffers in
1907 *	and play with them.
1908 *
1909 *	Inlined as it's very short and called for pretty much every
1910 *	packet ever received.
1911 */
1912
1913static inline void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
1914{
1915	skb_orphan(skb);
1916	skb->sk = sk;
1917	skb->destructor = sock_wfree;
1918	/*
1919	 * We used to take a refcount on sk, but following operation
1920	 * is enough to guarantee sk_free() wont free this sock until
1921	 * all in-flight packets are completed
1922	 */
1923	atomic_add(skb->truesize, &sk->sk_wmem_alloc);
1924}
1925
1926static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
1927{
1928	skb_orphan(skb);
1929	skb->sk = sk;
1930	skb->destructor = sock_rfree;
1931	atomic_add(skb->truesize, &sk->sk_rmem_alloc);
1932	sk_mem_charge(sk, skb->truesize);
1933}
1934
1935extern void sk_reset_timer(struct sock *sk, struct timer_list *timer,
1936			   unsigned long expires);
 
 
 
 
 
 
 
 
 
 
 
1937
1938extern void sk_stop_timer(struct sock *sk, struct timer_list *timer);
1939
1940extern int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
1941
1942extern int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
 
 
 
 
 
 
 
 
1943
1944/*
1945 *	Recover an error report and clear atomically
1946 */
1947
1948static inline int sock_error(struct sock *sk)
1949{
1950	int err;
1951	if (likely(!sk->sk_err))
 
 
 
 
1952		return 0;
 
1953	err = xchg(&sk->sk_err, 0);
1954	return -err;
1955}
1956
 
 
1957static inline unsigned long sock_wspace(struct sock *sk)
1958{
1959	int amt = 0;
1960
1961	if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
1962		amt = sk->sk_sndbuf - atomic_read(&sk->sk_wmem_alloc);
1963		if (amt < 0)
1964			amt = 0;
1965	}
1966	return amt;
1967}
1968
1969static inline void sk_wake_async(struct sock *sk, int how, int band)
 
 
 
 
1970{
1971	if (sock_flag(sk, SOCK_FASYNC))
1972		sock_wake_async(sk->sk_socket, how, band);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1973}
1974
1975#define SOCK_MIN_SNDBUF 2048
1976/*
1977 * Since sk_rmem_alloc sums skb->truesize, even a small frame might need
1978 * sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak
1979 */
1980#define SOCK_MIN_RCVBUF (2048 + sizeof(struct sk_buff))
 
 
 
1981
1982static inline void sk_stream_moderate_sndbuf(struct sock *sk)
1983{
1984	if (!(sk->sk_userlocks & SOCK_SNDBUF_LOCK)) {
1985		sk->sk_sndbuf = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
1986		sk->sk_sndbuf = max(sk->sk_sndbuf, SOCK_MIN_SNDBUF);
1987	}
 
 
 
 
1988}
1989
1990struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp);
 
1991
1992static inline struct page *sk_stream_alloc_page(struct sock *sk)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1993{
1994	struct page *page = NULL;
 
1995
1996	page = alloc_pages(sk->sk_allocation, 0);
1997	if (!page) {
1998		sk_enter_memory_pressure(sk);
1999		sk_stream_moderate_sndbuf(sk);
2000	}
2001	return page;
2002}
2003
 
 
2004/*
2005 *	Default write policy as shown to user space via poll/select/SIGIO
2006 */
2007static inline bool sock_writeable(const struct sock *sk)
2008{
2009	return atomic_read(&sk->sk_wmem_alloc) < (sk->sk_sndbuf >> 1);
2010}
2011
2012static inline gfp_t gfp_any(void)
2013{
2014	return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2015}
2016
2017static inline long sock_rcvtimeo(const struct sock *sk, bool noblock)
2018{
2019	return noblock ? 0 : sk->sk_rcvtimeo;
2020}
2021
2022static inline long sock_sndtimeo(const struct sock *sk, bool noblock)
2023{
2024	return noblock ? 0 : sk->sk_sndtimeo;
2025}
2026
2027static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
2028{
2029	return (waitall ? len : min_t(int, sk->sk_rcvlowat, len)) ? : 1;
 
 
2030}
2031
2032/* Alas, with timeout socket operations are not restartable.
2033 * Compare this to poll().
2034 */
2035static inline int sock_intr_errno(long timeo)
2036{
2037	return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
2038}
2039
2040extern void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
2041	struct sk_buff *skb);
2042extern void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
2043	struct sk_buff *skb);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2044
2045static inline void
2046sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
2047{
2048	ktime_t kt = skb->tstamp;
2049	struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
2050
2051	/*
2052	 * generate control messages if
2053	 * - receive time stamping in software requested (SOCK_RCVTSTAMP
2054	 *   or SOCK_TIMESTAMPING_RX_SOFTWARE)
2055	 * - software time stamp available and wanted
2056	 *   (SOCK_TIMESTAMPING_SOFTWARE)
2057	 * - hardware time stamps available and wanted
2058	 *   (SOCK_TIMESTAMPING_SYS_HARDWARE or
2059	 *   SOCK_TIMESTAMPING_RAW_HARDWARE)
2060	 */
2061	if (sock_flag(sk, SOCK_RCVTSTAMP) ||
2062	    sock_flag(sk, SOCK_TIMESTAMPING_RX_SOFTWARE) ||
2063	    (kt.tv64 && sock_flag(sk, SOCK_TIMESTAMPING_SOFTWARE)) ||
2064	    (hwtstamps->hwtstamp.tv64 &&
2065	     sock_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE)) ||
2066	    (hwtstamps->syststamp.tv64 &&
2067	     sock_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE)))
2068		__sock_recv_timestamp(msg, sk, skb);
2069	else
2070		sk->sk_stamp = kt;
2071
2072	if (sock_flag(sk, SOCK_WIFI_STATUS) && skb->wifi_acked_valid)
2073		__sock_recv_wifi_status(msg, sk, skb);
2074}
2075
2076extern void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2077				     struct sk_buff *skb);
2078
 
2079static inline void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2080					  struct sk_buff *skb)
2081{
2082#define FLAGS_TS_OR_DROPS ((1UL << SOCK_RXQ_OVFL)			| \
2083			   (1UL << SOCK_RCVTSTAMP)			| \
2084			   (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)	| \
2085			   (1UL << SOCK_TIMESTAMPING_SOFTWARE)		| \
2086			   (1UL << SOCK_TIMESTAMPING_RAW_HARDWARE)	| \
2087			   (1UL << SOCK_TIMESTAMPING_SYS_HARDWARE))
2088
2089	if (sk->sk_flags & FLAGS_TS_OR_DROPS)
2090		__sock_recv_ts_and_drops(msg, sk, skb);
2091	else
2092		sk->sk_stamp = skb->tstamp;
 
 
2093}
2094
 
 
2095/**
2096 * sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
2097 * @sk:		socket sending this packet
2098 * @tx_flags:	filled with instructions for time stamping
2099 *
2100 * Currently only depends on SOCK_TIMESTAMPING* flags. Returns error code if
2101 * parameters are invalid.
2102 */
2103extern int sock_tx_timestamp(struct sock *sk, __u8 *tx_flags);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2104
 
2105/**
2106 * sk_eat_skb - Release a skb if it is no longer needed
2107 * @sk: socket to eat this skb from
2108 * @skb: socket buffer to eat
2109 * @copied_early: flag indicating whether DMA operations copied this data early
2110 *
2111 * This routine must be called with interrupts disabled or with the socket
2112 * locked so that the sk_buff queue operation is ok.
2113*/
2114#ifdef CONFIG_NET_DMA
2115static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb, bool copied_early)
2116{
2117	__skb_unlink(skb, &sk->sk_receive_queue);
2118	if (!copied_early)
2119		__kfree_skb(skb);
2120	else
2121		__skb_queue_tail(&sk->sk_async_wait_queue, skb);
2122}
2123#else
2124static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb, bool copied_early)
2125{
2126	__skb_unlink(skb, &sk->sk_receive_queue);
 
 
 
 
 
 
2127	__kfree_skb(skb);
2128}
2129#endif
2130
2131static inline
2132struct net *sock_net(const struct sock *sk)
2133{
2134	return read_pnet(&sk->sk_net);
2135}
2136
2137static inline
2138void sock_net_set(struct sock *sk, struct net *net)
2139{
2140	write_pnet(&sk->sk_net, net);
2141}
2142
2143/*
2144 * Kernel sockets, f.e. rtnl or icmp_socket, are a part of a namespace.
2145 * They should not hold a reference to a namespace in order to allow
2146 * to stop it.
2147 * Sockets after sk_change_net should be released using sk_release_kernel
 
 
 
 
 
 
 
2148 */
2149static inline void sk_change_net(struct sock *sk, struct net *net)
 
 
 
 
 
 
2150{
2151	put_net(sock_net(sk));
2152	sock_net_set(sk, hold_net(net));
2153}
2154
2155static inline struct sock *skb_steal_sock(struct sk_buff *skb)
 
 
 
 
 
 
2156{
2157	if (unlikely(skb->sk)) {
2158		struct sock *sk = skb->sk;
2159
 
 
 
2160		skb->destructor = NULL;
2161		skb->sk = NULL;
2162		return sk;
2163	}
 
2164	return NULL;
2165}
2166
2167extern void sock_enable_timestamp(struct sock *sk, int flag);
2168extern int sock_get_timestamp(struct sock *, struct timeval __user *);
2169extern int sock_get_timestampns(struct sock *, struct timespec __user *);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2170
2171/*
2172 *	Enable debug/info messages
2173 */
2174extern int net_msg_warn;
2175#define NETDEBUG(fmt, args...) \
2176	do { if (net_msg_warn) printk(fmt,##args); } while (0)
 
 
 
 
 
2177
2178#define LIMIT_NETDEBUG(fmt, args...) \
2179	do { if (net_msg_warn && net_ratelimit()) printk(fmt,##args); } while(0)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2180
2181extern __u32 sysctl_wmem_max;
2182extern __u32 sysctl_rmem_max;
2183
2184extern void sk_init(void);
2185
2186extern int sysctl_optmem_max;
2187
2188extern __u32 sysctl_wmem_default;
2189extern __u32 sysctl_rmem_default;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2190
2191#endif	/* _SOCK_H */