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v6.13.7
   1/* SPDX-License-Identifier: GPL-2.0-or-later */
   2/*
   3 * INET		An implementation of the TCP/IP protocol suite for the LINUX
   4 *		operating system.  INET is implemented using the  BSD Socket
   5 *		interface as the means of communication with the user level.
   6 *
   7 *		Definitions for the AF_INET socket handler.
   8 *
   9 * Version:	@(#)sock.h	1.0.4	05/13/93
  10 *
  11 * Authors:	Ross Biro
  12 *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
  13 *		Corey Minyard <wf-rch!minyard@relay.EU.net>
  14 *		Florian La Roche <flla@stud.uni-sb.de>
  15 *
  16 * Fixes:
  17 *		Alan Cox	:	Volatiles in skbuff pointers. See
  18 *					skbuff comments. May be overdone,
  19 *					better to prove they can be removed
  20 *					than the reverse.
  21 *		Alan Cox	:	Added a zapped field for tcp to note
  22 *					a socket is reset and must stay shut up
  23 *		Alan Cox	:	New fields for options
  24 *	Pauline Middelink	:	identd support
  25 *		Alan Cox	:	Eliminate low level recv/recvfrom
  26 *		David S. Miller	:	New socket lookup architecture.
  27 *              Steve Whitehouse:       Default routines for sock_ops
  28 *              Arnaldo C. Melo :	removed net_pinfo, tp_pinfo and made
  29 *              			protinfo be just a void pointer, as the
  30 *              			protocol specific parts were moved to
  31 *              			respective headers and ipv4/v6, etc now
  32 *              			use private slabcaches for its socks
  33 *              Pedro Hortas	:	New flags field for socket options
 
 
 
 
 
 
  34 */
  35#ifndef _SOCK_H
  36#define _SOCK_H
  37
  38#include <linux/hardirq.h>
  39#include <linux/kernel.h>
  40#include <linux/list.h>
  41#include <linux/list_nulls.h>
  42#include <linux/timer.h>
  43#include <linux/cache.h>
  44#include <linux/bitops.h>
  45#include <linux/lockdep.h>
  46#include <linux/netdevice.h>
  47#include <linux/skbuff.h>	/* struct sk_buff */
  48#include <linux/mm.h>
  49#include <linux/security.h>
  50#include <linux/slab.h>
  51#include <linux/uaccess.h>
  52#include <linux/page_counter.h>
  53#include <linux/memcontrol.h>
 
  54#include <linux/static_key.h>
 
  55#include <linux/sched.h>
  56#include <linux/wait.h>
  57#include <linux/cgroup-defs.h>
  58#include <linux/rbtree.h>
  59#include <linux/rculist_nulls.h>
  60#include <linux/poll.h>
  61#include <linux/sockptr.h>
  62#include <linux/indirect_call_wrapper.h>
  63#include <linux/atomic.h>
  64#include <linux/refcount.h>
  65#include <linux/llist.h>
  66#include <net/dst.h>
  67#include <net/checksum.h>
  68#include <net/tcp_states.h>
  69#include <linux/net_tstamp.h>
  70#include <net/l3mdev.h>
  71#include <uapi/linux/socket.h>
  72
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  73/*
  74 * This structure really needs to be cleaned up.
  75 * Most of it is for TCP, and not used by any of
  76 * the other protocols.
  77 */
  78
 
 
 
 
 
 
 
 
 
 
 
 
 
  79/* This is the per-socket lock.  The spinlock provides a synchronization
  80 * between user contexts and software interrupt processing, whereas the
  81 * mini-semaphore synchronizes multiple users amongst themselves.
  82 */
  83typedef struct {
  84	spinlock_t		slock;
  85	int			owned;
  86	wait_queue_head_t	wq;
  87	/*
  88	 * We express the mutex-alike socket_lock semantics
  89	 * to the lock validator by explicitly managing
  90	 * the slock as a lock variant (in addition to
  91	 * the slock itself):
  92	 */
  93#ifdef CONFIG_DEBUG_LOCK_ALLOC
  94	struct lockdep_map dep_map;
  95#endif
  96} socket_lock_t;
  97
  98struct sock;
  99struct proto;
 100struct net;
 101
 102typedef __u32 __bitwise __portpair;
 103typedef __u64 __bitwise __addrpair;
 104
 105/**
 106 *	struct sock_common - minimal network layer representation of sockets
 107 *	@skc_daddr: Foreign IPv4 addr
 108 *	@skc_rcv_saddr: Bound local IPv4 addr
 109 *	@skc_addrpair: 8-byte-aligned __u64 union of @skc_daddr & @skc_rcv_saddr
 110 *	@skc_hash: hash value used with various protocol lookup tables
 111 *	@skc_u16hashes: two u16 hash values used by UDP lookup tables
 112 *	@skc_dport: placeholder for inet_dport/tw_dport
 113 *	@skc_num: placeholder for inet_num/tw_num
 114 *	@skc_portpair: __u32 union of @skc_dport & @skc_num
 115 *	@skc_family: network address family
 116 *	@skc_state: Connection state
 117 *	@skc_reuse: %SO_REUSEADDR setting
 118 *	@skc_reuseport: %SO_REUSEPORT setting
 119 *	@skc_ipv6only: socket is IPV6 only
 120 *	@skc_net_refcnt: socket is using net ref counting
 121 *	@skc_bound_dev_if: bound device index if != 0
 122 *	@skc_bind_node: bind hash linkage for various protocol lookup tables
 123 *	@skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol
 124 *	@skc_prot: protocol handlers inside a network family
 125 *	@skc_net: reference to the network namespace of this socket
 126 *	@skc_v6_daddr: IPV6 destination address
 127 *	@skc_v6_rcv_saddr: IPV6 source address
 128 *	@skc_cookie: socket's cookie value
 129 *	@skc_node: main hash linkage for various protocol lookup tables
 130 *	@skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol
 131 *	@skc_tx_queue_mapping: tx queue number for this connection
 132 *	@skc_rx_queue_mapping: rx queue number for this connection
 133 *	@skc_flags: place holder for sk_flags
 134 *		%SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE,
 135 *		%SO_OOBINLINE settings, %SO_TIMESTAMPING settings
 136 *	@skc_listener: connection request listener socket (aka rsk_listener)
 137 *		[union with @skc_flags]
 138 *	@skc_tw_dr: (aka tw_dr) ptr to &struct inet_timewait_death_row
 139 *		[union with @skc_flags]
 140 *	@skc_incoming_cpu: record/match cpu processing incoming packets
 141 *	@skc_rcv_wnd: (aka rsk_rcv_wnd) TCP receive window size (possibly scaled)
 142 *		[union with @skc_incoming_cpu]
 143 *	@skc_tw_rcv_nxt: (aka tw_rcv_nxt) TCP window next expected seq number
 144 *		[union with @skc_incoming_cpu]
 145 *	@skc_refcnt: reference count
 146 *
 147 *	This is the minimal network layer representation of sockets, the header
 148 *	for struct sock and struct inet_timewait_sock.
 149 */
 150struct sock_common {
 
 
 
 151	union {
 152		__addrpair	skc_addrpair;
 153		struct {
 154			__be32	skc_daddr;
 155			__be32	skc_rcv_saddr;
 156		};
 157	};
 158	union  {
 159		unsigned int	skc_hash;
 160		__u16		skc_u16hashes[2];
 161	};
 162	/* skc_dport && skc_num must be grouped as well */
 163	union {
 164		__portpair	skc_portpair;
 165		struct {
 166			__be16	skc_dport;
 167			__u16	skc_num;
 168		};
 169	};
 170
 171	unsigned short		skc_family;
 172	volatile unsigned char	skc_state;
 173	unsigned char		skc_reuse:4;
 174	unsigned char		skc_reuseport:1;
 175	unsigned char		skc_ipv6only:1;
 176	unsigned char		skc_net_refcnt:1;
 177	int			skc_bound_dev_if;
 178	union {
 179		struct hlist_node	skc_bind_node;
 180		struct hlist_node	skc_portaddr_node;
 181	};
 182	struct proto		*skc_prot;
 183	possible_net_t		skc_net;
 
 
 184
 185#if IS_ENABLED(CONFIG_IPV6)
 186	struct in6_addr		skc_v6_daddr;
 187	struct in6_addr		skc_v6_rcv_saddr;
 188#endif
 189
 190	atomic64_t		skc_cookie;
 191
 192	/* following fields are padding to force
 193	 * offset(struct sock, sk_refcnt) == 128 on 64bit arches
 194	 * assuming IPV6 is enabled. We use this padding differently
 195	 * for different kind of 'sockets'
 196	 */
 197	union {
 198		unsigned long	skc_flags;
 199		struct sock	*skc_listener; /* request_sock */
 200		struct inet_timewait_death_row *skc_tw_dr; /* inet_timewait_sock */
 201	};
 202	/*
 203	 * fields between dontcopy_begin/dontcopy_end
 204	 * are not copied in sock_copy()
 205	 */
 206	/* private: */
 207	int			skc_dontcopy_begin[0];
 208	/* public: */
 209	union {
 210		struct hlist_node	skc_node;
 211		struct hlist_nulls_node skc_nulls_node;
 212	};
 213	unsigned short		skc_tx_queue_mapping;
 214#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
 215	unsigned short		skc_rx_queue_mapping;
 216#endif
 217	union {
 218		int		skc_incoming_cpu;
 219		u32		skc_rcv_wnd;
 220		u32		skc_tw_rcv_nxt; /* struct tcp_timewait_sock  */
 221	};
 222
 223	refcount_t		skc_refcnt;
 224	/* private: */
 225	int                     skc_dontcopy_end[0];
 226	union {
 227		u32		skc_rxhash;
 228		u32		skc_window_clamp;
 229		u32		skc_tw_snd_nxt; /* struct tcp_timewait_sock */
 230	};
 231	/* public: */
 232};
 233
 234struct bpf_local_storage;
 235struct sk_filter;
 236
 237/**
 238  *	struct sock - network layer representation of sockets
 239  *	@__sk_common: shared layout with inet_timewait_sock
 240  *	@sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
 241  *	@sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
 242  *	@sk_lock:	synchronizer
 243  *	@sk_kern_sock: True if sock is using kernel lock classes
 244  *	@sk_rcvbuf: size of receive buffer in bytes
 245  *	@sk_wq: sock wait queue and async head
 246  *	@sk_rx_dst: receive input route used by early demux
 247  *	@sk_rx_dst_ifindex: ifindex for @sk_rx_dst
 248  *	@sk_rx_dst_cookie: cookie for @sk_rx_dst
 249  *	@sk_dst_cache: destination cache
 250  *	@sk_dst_pending_confirm: need to confirm neighbour
 251  *	@sk_policy: flow policy
 252  *	@sk_receive_queue: incoming packets
 253  *	@sk_wmem_alloc: transmit queue bytes committed
 254  *	@sk_tsq_flags: TCP Small Queues flags
 255  *	@sk_write_queue: Packet sending queue
 
 256  *	@sk_omem_alloc: "o" is "option" or "other"
 257  *	@sk_wmem_queued: persistent queue size
 258  *	@sk_forward_alloc: space allocated forward
 259  *	@sk_reserved_mem: space reserved and non-reclaimable for the socket
 260  *	@sk_napi_id: id of the last napi context to receive data for sk
 261  *	@sk_ll_usec: usecs to busypoll when there is no data
 262  *	@sk_allocation: allocation mode
 263  *	@sk_pacing_rate: Pacing rate (if supported by transport/packet scheduler)
 264  *	@sk_pacing_status: Pacing status (requested, handled by sch_fq)
 265  *	@sk_max_pacing_rate: Maximum pacing rate (%SO_MAX_PACING_RATE)
 266  *	@sk_sndbuf: size of send buffer in bytes
 267  *	@sk_no_check_tx: %SO_NO_CHECK setting, set checksum in TX packets
 268  *	@sk_no_check_rx: allow zero checksum in RX packets
 
 269  *	@sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
 270  *	@sk_gso_disabled: if set, NETIF_F_GSO_MASK is forbidden.
 271  *	@sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
 272  *	@sk_gso_max_size: Maximum GSO segment size to build
 273  *	@sk_gso_max_segs: Maximum number of GSO segments
 274  *	@sk_pacing_shift: scaling factor for TCP Small Queues
 275  *	@sk_lingertime: %SO_LINGER l_linger setting
 276  *	@sk_backlog: always used with the per-socket spinlock held
 277  *	@sk_callback_lock: used with the callbacks in the end of this struct
 278  *	@sk_error_queue: rarely used
 279  *	@sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt,
 280  *			  IPV6_ADDRFORM for instance)
 281  *	@sk_err: last error
 282  *	@sk_err_soft: errors that don't cause failure but are the cause of a
 283  *		      persistent failure not just 'timed out'
 284  *	@sk_drops: raw/udp drops counter
 285  *	@sk_ack_backlog: current listen backlog
 286  *	@sk_max_ack_backlog: listen backlog set in listen()
 287  *	@sk_uid: user id of owner
 288  *	@sk_prefer_busy_poll: prefer busypolling over softirq processing
 289  *	@sk_busy_poll_budget: napi processing budget when busypolling
 290  *	@sk_priority: %SO_PRIORITY setting
 
 291  *	@sk_type: socket type (%SOCK_STREAM, etc)
 292  *	@sk_protocol: which protocol this socket belongs in this network family
 293  *	@sk_peer_lock: lock protecting @sk_peer_pid and @sk_peer_cred
 294  *	@sk_peer_pid: &struct pid for this socket's peer
 295  *	@sk_peer_cred: %SO_PEERCRED setting
 296  *	@sk_rcvlowat: %SO_RCVLOWAT setting
 297  *	@sk_rcvtimeo: %SO_RCVTIMEO setting
 298  *	@sk_sndtimeo: %SO_SNDTIMEO setting
 299  *	@sk_txhash: computed flow hash for use on transmit
 300  *	@sk_txrehash: enable TX hash rethink
 301  *	@sk_filter: socket filtering instructions
 
 302  *	@sk_timer: sock cleanup timer
 303  *	@sk_stamp: time stamp of last packet received
 304  *	@sk_stamp_seq: lock for accessing sk_stamp on 32 bit architectures only
 305  *	@sk_tsflags: SO_TIMESTAMPING flags
 306  *	@sk_use_task_frag: allow sk_page_frag() to use current->task_frag.
 307  *			   Sockets that can be used under memory reclaim should
 308  *			   set this to false.
 309  *	@sk_bind_phc: SO_TIMESTAMPING bind PHC index of PTP virtual clock
 310  *	              for timestamping
 311  *	@sk_tskey: counter to disambiguate concurrent tstamp requests
 312  *	@sk_zckey: counter to order MSG_ZEROCOPY notifications
 313  *	@sk_socket: Identd and reporting IO signals
 314  *	@sk_user_data: RPC layer private data. Write-protected by @sk_callback_lock.
 315  *	@sk_frag: cached page frag
 316  *	@sk_peek_off: current peek_offset value
 317  *	@sk_send_head: front of stuff to transmit
 318  *	@tcp_rtx_queue: TCP re-transmit queue [union with @sk_send_head]
 319  *	@sk_security: used by security modules
 320  *	@sk_mark: generic packet mark
 321  *	@sk_cgrp_data: cgroup data for this cgroup
 322  *	@sk_memcg: this socket's memory cgroup association
 323  *	@sk_write_pending: a write to stream socket waits to start
 324  *	@sk_disconnects: number of disconnect operations performed on this sock
 325  *	@sk_state_change: callback to indicate change in the state of the sock
 326  *	@sk_data_ready: callback to indicate there is data to be processed
 327  *	@sk_write_space: callback to indicate there is bf sending space available
 328  *	@sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
 329  *	@sk_backlog_rcv: callback to process the backlog
 330  *	@sk_validate_xmit_skb: ptr to an optional validate function
 331  *	@sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
 332  *	@sk_reuseport_cb: reuseport group container
 333  *	@sk_bpf_storage: ptr to cache and control for bpf_sk_storage
 334  *	@sk_rcu: used during RCU grace period
 335  *	@sk_clockid: clockid used by time-based scheduling (SO_TXTIME)
 336  *	@sk_txtime_deadline_mode: set deadline mode for SO_TXTIME
 337  *	@sk_txtime_report_errors: set report errors mode for SO_TXTIME
 338  *	@sk_txtime_unused: unused txtime flags
 339  *	@ns_tracker: tracker for netns reference
 340  *	@sk_user_frags: xarray of pages the user is holding a reference on.
 341  */
 342struct sock {
 343	/*
 344	 * Now struct inet_timewait_sock also uses sock_common, so please just
 345	 * don't add nothing before this first member (__sk_common) --acme
 346	 */
 347	struct sock_common	__sk_common;
 348#define sk_node			__sk_common.skc_node
 349#define sk_nulls_node		__sk_common.skc_nulls_node
 350#define sk_refcnt		__sk_common.skc_refcnt
 351#define sk_tx_queue_mapping	__sk_common.skc_tx_queue_mapping
 352#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
 353#define sk_rx_queue_mapping	__sk_common.skc_rx_queue_mapping
 354#endif
 355
 356#define sk_dontcopy_begin	__sk_common.skc_dontcopy_begin
 357#define sk_dontcopy_end		__sk_common.skc_dontcopy_end
 358#define sk_hash			__sk_common.skc_hash
 359#define sk_portpair		__sk_common.skc_portpair
 360#define sk_num			__sk_common.skc_num
 361#define sk_dport		__sk_common.skc_dport
 362#define sk_addrpair		__sk_common.skc_addrpair
 363#define sk_daddr		__sk_common.skc_daddr
 364#define sk_rcv_saddr		__sk_common.skc_rcv_saddr
 365#define sk_family		__sk_common.skc_family
 366#define sk_state		__sk_common.skc_state
 367#define sk_reuse		__sk_common.skc_reuse
 368#define sk_reuseport		__sk_common.skc_reuseport
 369#define sk_ipv6only		__sk_common.skc_ipv6only
 370#define sk_net_refcnt		__sk_common.skc_net_refcnt
 371#define sk_bound_dev_if		__sk_common.skc_bound_dev_if
 372#define sk_bind_node		__sk_common.skc_bind_node
 373#define sk_prot			__sk_common.skc_prot
 374#define sk_net			__sk_common.skc_net
 375#define sk_v6_daddr		__sk_common.skc_v6_daddr
 376#define sk_v6_rcv_saddr	__sk_common.skc_v6_rcv_saddr
 377#define sk_cookie		__sk_common.skc_cookie
 378#define sk_incoming_cpu		__sk_common.skc_incoming_cpu
 379#define sk_flags		__sk_common.skc_flags
 380#define sk_rxhash		__sk_common.skc_rxhash
 381
 382	__cacheline_group_begin(sock_write_rx);
 383
 384	atomic_t		sk_drops;
 385	__s32			sk_peek_off;
 386	struct sk_buff_head	sk_error_queue;
 387	struct sk_buff_head	sk_receive_queue;
 388	/*
 389	 * The backlog queue is special, it is always used with
 390	 * the per-socket spinlock held and requires low latency
 391	 * access. Therefore we special case it's implementation.
 392	 * Note : rmem_alloc is in this structure to fill a hole
 393	 * on 64bit arches, not because its logically part of
 394	 * backlog.
 395	 */
 396	struct {
 397		atomic_t	rmem_alloc;
 398		int		len;
 399		struct sk_buff	*head;
 400		struct sk_buff	*tail;
 401	} sk_backlog;
 402#define sk_rmem_alloc sk_backlog.rmem_alloc
 403
 404	__cacheline_group_end(sock_write_rx);
 405
 406	__cacheline_group_begin(sock_read_rx);
 407	/* early demux fields */
 408	struct dst_entry __rcu	*sk_rx_dst;
 409	int			sk_rx_dst_ifindex;
 410	u32			sk_rx_dst_cookie;
 411
 412#ifdef CONFIG_NET_RX_BUSY_POLL
 413	unsigned int		sk_ll_usec;
 414	unsigned int		sk_napi_id;
 415	u16			sk_busy_poll_budget;
 416	u8			sk_prefer_busy_poll;
 417#endif
 418	u8			sk_userlocks;
 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
 429	void			(*sk_data_ready)(struct sock *sk);
 430	long			sk_rcvtimeo;
 431	int			sk_rcvlowat;
 432	__cacheline_group_end(sock_read_rx);
 433
 434	__cacheline_group_begin(sock_read_rxtx);
 435	int			sk_err;
 436	struct socket		*sk_socket;
 437	struct mem_cgroup	*sk_memcg;
 438#ifdef CONFIG_XFRM
 439	struct xfrm_policy __rcu *sk_policy[2];
 440#endif
 441	__cacheline_group_end(sock_read_rxtx);
 442
 443	__cacheline_group_begin(sock_write_rxtx);
 444	socket_lock_t		sk_lock;
 445	u32			sk_reserved_mem;
 446	int			sk_forward_alloc;
 447	u32			sk_tsflags;
 448	__cacheline_group_end(sock_write_rxtx);
 449
 450	__cacheline_group_begin(sock_write_tx);
 451	int			sk_write_pending;
 452	atomic_t		sk_omem_alloc;
 453	int			sk_sndbuf;
 454
 455	int			sk_wmem_queued;
 456	refcount_t		sk_wmem_alloc;
 457	unsigned long		sk_tsq_flags;
 458	union {
 459		struct sk_buff	*sk_send_head;
 460		struct rb_root	tcp_rtx_queue;
 461	};
 462	struct sk_buff_head	sk_write_queue;
 463	u32			sk_dst_pending_confirm;
 464	u32			sk_pacing_status; /* see enum sk_pacing */
 465	struct page_frag	sk_frag;
 466	struct timer_list	sk_timer;
 467
 468	unsigned long		sk_pacing_rate; /* bytes per second */
 469	atomic_t		sk_zckey;
 470	atomic_t		sk_tskey;
 471	__cacheline_group_end(sock_write_tx);
 472
 473	__cacheline_group_begin(sock_read_tx);
 474	unsigned long		sk_max_pacing_rate;
 475	long			sk_sndtimeo;
 476	u32			sk_priority;
 477	u32			sk_mark;
 478	struct dst_entry __rcu	*sk_dst_cache;
 479	netdev_features_t	sk_route_caps;
 480#ifdef CONFIG_SOCK_VALIDATE_XMIT
 481	struct sk_buff*		(*sk_validate_xmit_skb)(struct sock *sk,
 482							struct net_device *dev,
 483							struct sk_buff *skb);
 484#endif
 485	u16			sk_gso_type;
 486	u16			sk_gso_max_segs;
 487	unsigned int		sk_gso_max_size;
 488	gfp_t			sk_allocation;
 489	u32			sk_txhash;
 490	u8			sk_pacing_shift;
 491	bool			sk_use_task_frag;
 492	__cacheline_group_end(sock_read_tx);
 493
 494	/*
 495	 * Because of non atomicity rules, all
 496	 * changes are protected by socket lock.
 497	 */
 498	u8			sk_gso_disabled : 1,
 499				sk_kern_sock : 1,
 500				sk_no_check_tx : 1,
 501				sk_no_check_rx : 1;
 502	u8			sk_shutdown;
 503	u16			sk_type;
 504	u16			sk_protocol;
 505	unsigned long	        sk_lingertime;
 
 506	struct proto		*sk_prot_creator;
 507	rwlock_t		sk_callback_lock;
 508	int			sk_err_soft;
 509	u32			sk_ack_backlog;
 510	u32			sk_max_ack_backlog;
 511	kuid_t			sk_uid;
 512	spinlock_t		sk_peer_lock;
 513	int			sk_bind_phc;
 
 
 514	struct pid		*sk_peer_pid;
 515	const struct cred	*sk_peer_cred;
 516
 
 
 
 517	ktime_t			sk_stamp;
 518#if BITS_PER_LONG==32
 519	seqlock_t		sk_stamp_seq;
 520#endif
 521	int			sk_disconnects;
 522
 523	u8			sk_txrehash;
 524	u8			sk_clockid;
 525	u8			sk_txtime_deadline_mode : 1,
 526				sk_txtime_report_errors : 1,
 527				sk_txtime_unused : 6;
 528
 529	void			*sk_user_data;
 
 
 
 
 530#ifdef CONFIG_SECURITY
 531	void			*sk_security;
 532#endif
 533	struct sock_cgroup_data	sk_cgrp_data;
 
 
 534	void			(*sk_state_change)(struct sock *sk);
 
 535	void			(*sk_write_space)(struct sock *sk);
 536	void			(*sk_error_report)(struct sock *sk);
 537	int			(*sk_backlog_rcv)(struct sock *sk,
 538						  struct sk_buff *skb);
 539	void                    (*sk_destruct)(struct sock *sk);
 540	struct sock_reuseport __rcu	*sk_reuseport_cb;
 541#ifdef CONFIG_BPF_SYSCALL
 542	struct bpf_local_storage __rcu	*sk_bpf_storage;
 543#endif
 544	struct rcu_head		sk_rcu;
 545	netns_tracker		ns_tracker;
 546	struct xarray		sk_user_frags;
 547};
 548
 549struct sock_bh_locked {
 550	struct sock *sock;
 551	local_lock_t bh_lock;
 552};
 553
 554enum sk_pacing {
 555	SK_PACING_NONE		= 0,
 556	SK_PACING_NEEDED	= 1,
 557	SK_PACING_FQ		= 2,
 558};
 559
 560/* flag bits in sk_user_data
 561 *
 562 * - SK_USER_DATA_NOCOPY:      Pointer stored in sk_user_data might
 563 *   not be suitable for copying when cloning the socket. For instance,
 564 *   it can point to a reference counted object. sk_user_data bottom
 565 *   bit is set if pointer must not be copied.
 566 *
 567 * - SK_USER_DATA_BPF:         Mark whether sk_user_data field is
 568 *   managed/owned by a BPF reuseport array. This bit should be set
 569 *   when sk_user_data's sk is added to the bpf's reuseport_array.
 570 *
 571 * - SK_USER_DATA_PSOCK:       Mark whether pointer stored in
 572 *   sk_user_data points to psock type. This bit should be set
 573 *   when sk_user_data is assigned to a psock object.
 574 */
 575#define SK_USER_DATA_NOCOPY	1UL
 576#define SK_USER_DATA_BPF	2UL
 577#define SK_USER_DATA_PSOCK	4UL
 578#define SK_USER_DATA_PTRMASK	~(SK_USER_DATA_NOCOPY | SK_USER_DATA_BPF |\
 579				  SK_USER_DATA_PSOCK)
 580
 581/**
 582 * sk_user_data_is_nocopy - Test if sk_user_data pointer must not be copied
 583 * @sk: socket
 584 */
 585static inline bool sk_user_data_is_nocopy(const struct sock *sk)
 586{
 587	return ((uintptr_t)sk->sk_user_data & SK_USER_DATA_NOCOPY);
 588}
 589
 590#define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data)))
 591
 592/**
 593 * __locked_read_sk_user_data_with_flags - return the pointer
 594 * only if argument flags all has been set in sk_user_data. Otherwise
 595 * return NULL
 596 *
 597 * @sk: socket
 598 * @flags: flag bits
 599 *
 600 * The caller must be holding sk->sk_callback_lock.
 601 */
 602static inline void *
 603__locked_read_sk_user_data_with_flags(const struct sock *sk,
 604				      uintptr_t flags)
 605{
 606	uintptr_t sk_user_data =
 607		(uintptr_t)rcu_dereference_check(__sk_user_data(sk),
 608						 lockdep_is_held(&sk->sk_callback_lock));
 609
 610	WARN_ON_ONCE(flags & SK_USER_DATA_PTRMASK);
 611
 612	if ((sk_user_data & flags) == flags)
 613		return (void *)(sk_user_data & SK_USER_DATA_PTRMASK);
 614	return NULL;
 615}
 616
 617/**
 618 * __rcu_dereference_sk_user_data_with_flags - return the pointer
 619 * only if argument flags all has been set in sk_user_data. Otherwise
 620 * return NULL
 621 *
 622 * @sk: socket
 623 * @flags: flag bits
 624 */
 625static inline void *
 626__rcu_dereference_sk_user_data_with_flags(const struct sock *sk,
 627					  uintptr_t flags)
 628{
 629	uintptr_t sk_user_data = (uintptr_t)rcu_dereference(__sk_user_data(sk));
 630
 631	WARN_ON_ONCE(flags & SK_USER_DATA_PTRMASK);
 632
 633	if ((sk_user_data & flags) == flags)
 634		return (void *)(sk_user_data & SK_USER_DATA_PTRMASK);
 635	return NULL;
 636}
 637
 638#define rcu_dereference_sk_user_data(sk)				\
 639	__rcu_dereference_sk_user_data_with_flags(sk, 0)
 640#define __rcu_assign_sk_user_data_with_flags(sk, ptr, flags)		\
 641({									\
 642	uintptr_t __tmp1 = (uintptr_t)(ptr),				\
 643		  __tmp2 = (uintptr_t)(flags);				\
 644	WARN_ON_ONCE(__tmp1 & ~SK_USER_DATA_PTRMASK);			\
 645	WARN_ON_ONCE(__tmp2 & SK_USER_DATA_PTRMASK);			\
 646	rcu_assign_pointer(__sk_user_data((sk)),			\
 647			   __tmp1 | __tmp2);				\
 648})
 649#define rcu_assign_sk_user_data(sk, ptr)				\
 650	__rcu_assign_sk_user_data_with_flags(sk, ptr, 0)
 651
 652static inline
 653struct net *sock_net(const struct sock *sk)
 654{
 655	return read_pnet(&sk->sk_net);
 656}
 657
 658static inline
 659void sock_net_set(struct sock *sk, struct net *net)
 660{
 661	write_pnet(&sk->sk_net, net);
 662}
 663
 664/*
 665 * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK
 666 * or not whether his port will be reused by someone else. SK_FORCE_REUSE
 667 * on a socket means that the socket will reuse everybody else's port
 668 * without looking at the other's sk_reuse value.
 669 */
 670
 671#define SK_NO_REUSE	0
 672#define SK_CAN_REUSE	1
 673#define SK_FORCE_REUSE	2
 674
 675int sk_set_peek_off(struct sock *sk, int val);
 676
 677static inline int sk_peek_offset(const struct sock *sk, int flags)
 678{
 679	if (unlikely(flags & MSG_PEEK)) {
 680		return READ_ONCE(sk->sk_peek_off);
 681	}
 682
 683	return 0;
 684}
 685
 686static inline void sk_peek_offset_bwd(struct sock *sk, int val)
 687{
 688	s32 off = READ_ONCE(sk->sk_peek_off);
 689
 690	if (unlikely(off >= 0)) {
 691		off = max_t(s32, off - val, 0);
 692		WRITE_ONCE(sk->sk_peek_off, off);
 693	}
 694}
 695
 696static inline void sk_peek_offset_fwd(struct sock *sk, int val)
 697{
 698	sk_peek_offset_bwd(sk, -val);
 
 699}
 700
 701/*
 702 * Hashed lists helper routines
 703 */
 704static inline struct sock *sk_entry(const struct hlist_node *node)
 705{
 706	return hlist_entry(node, struct sock, sk_node);
 707}
 708
 709static inline struct sock *__sk_head(const struct hlist_head *head)
 710{
 711	return hlist_entry(head->first, struct sock, sk_node);
 712}
 713
 714static inline struct sock *sk_head(const struct hlist_head *head)
 715{
 716	return hlist_empty(head) ? NULL : __sk_head(head);
 717}
 718
 719static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head)
 720{
 721	return hlist_nulls_entry(head->first, struct sock, sk_nulls_node);
 722}
 723
 724static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head)
 725{
 726	return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head);
 727}
 728
 729static inline struct sock *sk_next(const struct sock *sk)
 730{
 731	return hlist_entry_safe(sk->sk_node.next, struct sock, sk_node);
 
 732}
 733
 734static inline struct sock *sk_nulls_next(const struct sock *sk)
 735{
 736	return (!is_a_nulls(sk->sk_nulls_node.next)) ?
 737		hlist_nulls_entry(sk->sk_nulls_node.next,
 738				  struct sock, sk_nulls_node) :
 739		NULL;
 740}
 741
 742static inline bool sk_unhashed(const struct sock *sk)
 743{
 744	return hlist_unhashed(&sk->sk_node);
 745}
 746
 747static inline bool sk_hashed(const struct sock *sk)
 748{
 749	return !sk_unhashed(sk);
 750}
 751
 752static inline void sk_node_init(struct hlist_node *node)
 753{
 754	node->pprev = NULL;
 755}
 756
 
 
 
 
 
 757static inline void __sk_del_node(struct sock *sk)
 758{
 759	__hlist_del(&sk->sk_node);
 760}
 761
 762/* NB: equivalent to hlist_del_init_rcu */
 763static inline bool __sk_del_node_init(struct sock *sk)
 764{
 765	if (sk_hashed(sk)) {
 766		__sk_del_node(sk);
 767		sk_node_init(&sk->sk_node);
 768		return true;
 769	}
 770	return false;
 771}
 772
 773/* Grab socket reference count. This operation is valid only
 774   when sk is ALREADY grabbed f.e. it is found in hash table
 775   or a list and the lookup is made under lock preventing hash table
 776   modifications.
 777 */
 778
 779static __always_inline void sock_hold(struct sock *sk)
 780{
 781	refcount_inc(&sk->sk_refcnt);
 782}
 783
 784/* Ungrab socket in the context, which assumes that socket refcnt
 785   cannot hit zero, f.e. it is true in context of any socketcall.
 786 */
 787static __always_inline void __sock_put(struct sock *sk)
 788{
 789	refcount_dec(&sk->sk_refcnt);
 790}
 791
 792static inline bool sk_del_node_init(struct sock *sk)
 793{
 794	bool rc = __sk_del_node_init(sk);
 795
 796	if (rc) {
 797		/* paranoid for a while -acme */
 798		WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
 799		__sock_put(sk);
 800	}
 801	return rc;
 802}
 803#define sk_del_node_init_rcu(sk)	sk_del_node_init(sk)
 804
 805static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk)
 806{
 807	if (sk_hashed(sk)) {
 808		hlist_nulls_del_init_rcu(&sk->sk_nulls_node);
 809		return true;
 810	}
 811	return false;
 812}
 813
 814static inline bool sk_nulls_del_node_init_rcu(struct sock *sk)
 815{
 816	bool rc = __sk_nulls_del_node_init_rcu(sk);
 817
 818	if (rc) {
 819		/* paranoid for a while -acme */
 820		WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
 821		__sock_put(sk);
 822	}
 823	return rc;
 824}
 825
 826static inline void __sk_add_node(struct sock *sk, struct hlist_head *list)
 827{
 828	hlist_add_head(&sk->sk_node, list);
 829}
 830
 831static inline void sk_add_node(struct sock *sk, struct hlist_head *list)
 832{
 833	sock_hold(sk);
 834	__sk_add_node(sk, list);
 835}
 836
 837static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list)
 838{
 839	sock_hold(sk);
 840	if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport &&
 841	    sk->sk_family == AF_INET6)
 842		hlist_add_tail_rcu(&sk->sk_node, list);
 843	else
 844		hlist_add_head_rcu(&sk->sk_node, list);
 845}
 846
 847static inline void sk_add_node_tail_rcu(struct sock *sk, struct hlist_head *list)
 848{
 849	sock_hold(sk);
 850	hlist_add_tail_rcu(&sk->sk_node, list);
 851}
 852
 853static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
 854{
 855	hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list);
 856}
 857
 858static inline void __sk_nulls_add_node_tail_rcu(struct sock *sk, struct hlist_nulls_head *list)
 859{
 860	hlist_nulls_add_tail_rcu(&sk->sk_nulls_node, list);
 861}
 862
 863static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
 864{
 865	sock_hold(sk);
 866	__sk_nulls_add_node_rcu(sk, list);
 867}
 868
 869static inline void __sk_del_bind_node(struct sock *sk)
 870{
 871	__hlist_del(&sk->sk_bind_node);
 872}
 873
 874static inline void sk_add_bind_node(struct sock *sk,
 875					struct hlist_head *list)
 876{
 877	hlist_add_head(&sk->sk_bind_node, list);
 878}
 879
 880#define sk_for_each(__sk, list) \
 881	hlist_for_each_entry(__sk, list, sk_node)
 882#define sk_for_each_rcu(__sk, list) \
 883	hlist_for_each_entry_rcu(__sk, list, sk_node)
 884#define sk_nulls_for_each(__sk, node, list) \
 885	hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)
 886#define sk_nulls_for_each_rcu(__sk, node, list) \
 887	hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)
 888#define sk_for_each_from(__sk) \
 889	hlist_for_each_entry_from(__sk, sk_node)
 890#define sk_nulls_for_each_from(__sk, node) \
 891	if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \
 892		hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node)
 893#define sk_for_each_safe(__sk, tmp, list) \
 894	hlist_for_each_entry_safe(__sk, tmp, list, sk_node)
 895#define sk_for_each_bound(__sk, list) \
 896	hlist_for_each_entry(__sk, list, sk_bind_node)
 897#define sk_for_each_bound_safe(__sk, tmp, list) \
 898	hlist_for_each_entry_safe(__sk, tmp, list, sk_bind_node)
 899
 900/**
 901 * sk_for_each_entry_offset_rcu - iterate over a list at a given struct offset
 902 * @tpos:	the type * to use as a loop cursor.
 903 * @pos:	the &struct hlist_node to use as a loop cursor.
 904 * @head:	the head for your list.
 905 * @offset:	offset of hlist_node within the struct.
 906 *
 907 */
 908#define sk_for_each_entry_offset_rcu(tpos, pos, head, offset)		       \
 909	for (pos = rcu_dereference(hlist_first_rcu(head));		       \
 910	     pos != NULL &&						       \
 911		({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;});       \
 912	     pos = rcu_dereference(hlist_next_rcu(pos)))
 913
 914static inline struct user_namespace *sk_user_ns(const struct sock *sk)
 915{
 916	/* Careful only use this in a context where these parameters
 917	 * can not change and must all be valid, such as recvmsg from
 918	 * userspace.
 919	 */
 920	return sk->sk_socket->file->f_cred->user_ns;
 921}
 922
 923/* Sock flags */
 924enum sock_flags {
 925	SOCK_DEAD,
 926	SOCK_DONE,
 927	SOCK_URGINLINE,
 928	SOCK_KEEPOPEN,
 929	SOCK_LINGER,
 930	SOCK_DESTROY,
 931	SOCK_BROADCAST,
 932	SOCK_TIMESTAMP,
 933	SOCK_ZAPPED,
 934	SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */
 935	SOCK_DBG, /* %SO_DEBUG setting */
 936	SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
 937	SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */
 938	SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
 
 939	SOCK_MEMALLOC, /* VM depends on this socket for swapping */
 
 
 
 940	SOCK_TIMESTAMPING_RX_SOFTWARE,  /* %SOF_TIMESTAMPING_RX_SOFTWARE */
 
 
 
 941	SOCK_FASYNC, /* fasync() active */
 942	SOCK_RXQ_OVFL,
 943	SOCK_ZEROCOPY, /* buffers from userspace */
 944	SOCK_WIFI_STATUS, /* push wifi status to userspace */
 945	SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS.
 946		     * Will use last 4 bytes of packet sent from
 947		     * user-space instead.
 948		     */
 949	SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */
 950	SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */
 951	SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */
 952	SOCK_TXTIME,
 953	SOCK_XDP, /* XDP is attached */
 954	SOCK_TSTAMP_NEW, /* Indicates 64 bit timestamps always */
 955	SOCK_RCVMARK, /* Receive SO_MARK  ancillary data with packet */
 956};
 957
 958#define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))
 959/*
 960 * The highest bit of sk_tsflags is reserved for kernel-internal
 961 * SOCKCM_FLAG_TS_OPT_ID. There is a check in core/sock.c to control that
 962 * SOF_TIMESTAMPING* values do not reach this reserved area
 963 */
 964#define SOCKCM_FLAG_TS_OPT_ID	BIT(31)
 965
 966static inline void sock_copy_flags(struct sock *nsk, const struct sock *osk)
 967{
 968	nsk->sk_flags = osk->sk_flags;
 969}
 970
 971static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
 972{
 973	__set_bit(flag, &sk->sk_flags);
 974}
 975
 976static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag)
 977{
 978	__clear_bit(flag, &sk->sk_flags);
 979}
 980
 981static inline void sock_valbool_flag(struct sock *sk, enum sock_flags bit,
 982				     int valbool)
 983{
 984	if (valbool)
 985		sock_set_flag(sk, bit);
 986	else
 987		sock_reset_flag(sk, bit);
 988}
 989
 990static inline bool sock_flag(const struct sock *sk, enum sock_flags flag)
 991{
 992	return test_bit(flag, &sk->sk_flags);
 993}
 994
 995#ifdef CONFIG_NET
 996DECLARE_STATIC_KEY_FALSE(memalloc_socks_key);
 997static inline int sk_memalloc_socks(void)
 998{
 999	return static_branch_unlikely(&memalloc_socks_key);
1000}
1001
1002void __receive_sock(struct file *file);
1003#else
1004
1005static inline int sk_memalloc_socks(void)
1006{
1007	return 0;
1008}
1009
1010static inline void __receive_sock(struct file *file)
1011{ }
1012#endif
1013
1014static inline gfp_t sk_gfp_mask(const struct sock *sk, gfp_t gfp_mask)
1015{
1016	return gfp_mask | (sk->sk_allocation & __GFP_MEMALLOC);
1017}
1018
1019static inline void sk_acceptq_removed(struct sock *sk)
1020{
1021	WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog - 1);
1022}
1023
1024static inline void sk_acceptq_added(struct sock *sk)
1025{
1026	WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog + 1);
1027}
1028
1029/* Note: If you think the test should be:
1030 *	return READ_ONCE(sk->sk_ack_backlog) >= READ_ONCE(sk->sk_max_ack_backlog);
1031 * Then please take a look at commit 64a146513f8f ("[NET]: Revert incorrect accept queue backlog changes.")
1032 */
1033static inline bool sk_acceptq_is_full(const struct sock *sk)
1034{
1035	return READ_ONCE(sk->sk_ack_backlog) > READ_ONCE(sk->sk_max_ack_backlog);
1036}
1037
1038/*
1039 * Compute minimal free write space needed to queue new packets.
1040 */
1041static inline int sk_stream_min_wspace(const struct sock *sk)
1042{
1043	return READ_ONCE(sk->sk_wmem_queued) >> 1;
1044}
1045
1046static inline int sk_stream_wspace(const struct sock *sk)
1047{
1048	return READ_ONCE(sk->sk_sndbuf) - READ_ONCE(sk->sk_wmem_queued);
1049}
1050
1051static inline void sk_wmem_queued_add(struct sock *sk, int val)
1052{
1053	WRITE_ONCE(sk->sk_wmem_queued, sk->sk_wmem_queued + val);
1054}
1055
1056static inline void sk_forward_alloc_add(struct sock *sk, int val)
1057{
1058	/* Paired with lockless reads of sk->sk_forward_alloc */
1059	WRITE_ONCE(sk->sk_forward_alloc, sk->sk_forward_alloc + val);
1060}
1061
1062void sk_stream_write_space(struct sock *sk);
1063
1064/* OOB backlog add */
1065static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
1066{
1067	/* dont let skb dst not refcounted, we are going to leave rcu lock */
1068	skb_dst_force(skb);
1069
1070	if (!sk->sk_backlog.tail)
1071		WRITE_ONCE(sk->sk_backlog.head, skb);
1072	else
1073		sk->sk_backlog.tail->next = skb;
1074
1075	WRITE_ONCE(sk->sk_backlog.tail, skb);
1076	skb->next = NULL;
1077}
1078
1079/*
1080 * Take into account size of receive queue and backlog queue
1081 * Do not take into account this skb truesize,
1082 * to allow even a single big packet to come.
1083 */
1084static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit)
 
1085{
1086	unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc);
1087
1088	return qsize > limit;
1089}
1090
1091/* The per-socket spinlock must be held here. */
1092static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb,
1093					      unsigned int limit)
1094{
1095	if (sk_rcvqueues_full(sk, limit))
1096		return -ENOBUFS;
1097
1098	/*
1099	 * If the skb was allocated from pfmemalloc reserves, only
1100	 * allow SOCK_MEMALLOC sockets to use it as this socket is
1101	 * helping free memory
1102	 */
1103	if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC))
1104		return -ENOMEM;
1105
1106	__sk_add_backlog(sk, skb);
1107	sk->sk_backlog.len += skb->truesize;
1108	return 0;
1109}
1110
1111int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb);
1112
1113INDIRECT_CALLABLE_DECLARE(int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb));
1114INDIRECT_CALLABLE_DECLARE(int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb));
1115
1116static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
1117{
1118	if (sk_memalloc_socks() && skb_pfmemalloc(skb))
1119		return __sk_backlog_rcv(sk, skb);
1120
1121	return INDIRECT_CALL_INET(sk->sk_backlog_rcv,
1122				  tcp_v6_do_rcv,
1123				  tcp_v4_do_rcv,
1124				  sk, skb);
 
 
 
 
 
 
 
 
 
1125}
1126
1127static inline void sk_incoming_cpu_update(struct sock *sk)
1128{
1129	int cpu = raw_smp_processor_id();
 
 
 
 
 
 
 
 
1130
1131	if (unlikely(READ_ONCE(sk->sk_incoming_cpu) != cpu))
1132		WRITE_ONCE(sk->sk_incoming_cpu, cpu);
 
 
 
1133}
1134
 
 
 
 
 
 
1135
1136static inline void sock_rps_save_rxhash(struct sock *sk,
1137					const struct sk_buff *skb)
1138{
1139#ifdef CONFIG_RPS
1140	/* The following WRITE_ONCE() is paired with the READ_ONCE()
1141	 * here, and another one in sock_rps_record_flow().
1142	 */
1143	if (unlikely(READ_ONCE(sk->sk_rxhash) != skb->hash))
1144		WRITE_ONCE(sk->sk_rxhash, skb->hash);
1145#endif
1146}
1147
1148static inline void sock_rps_reset_rxhash(struct sock *sk)
1149{
1150#ifdef CONFIG_RPS
1151	/* Paired with READ_ONCE() in sock_rps_record_flow() */
1152	WRITE_ONCE(sk->sk_rxhash, 0);
1153#endif
1154}
1155
1156#define sk_wait_event(__sk, __timeo, __condition, __wait)		\
1157	({	int __rc, __dis = __sk->sk_disconnects;			\
1158		release_sock(__sk);					\
1159		__rc = __condition;					\
1160		if (!__rc) {						\
1161			*(__timeo) = wait_woken(__wait,			\
1162						TASK_INTERRUPTIBLE,	\
1163						*(__timeo));		\
1164		}							\
1165		sched_annotate_sleep();					\
1166		lock_sock(__sk);					\
1167		__rc = __dis == __sk->sk_disconnects ? __condition : -EPIPE; \
1168		__rc;							\
1169	})
1170
1171int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
1172int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
1173void sk_stream_wait_close(struct sock *sk, long timeo_p);
1174int sk_stream_error(struct sock *sk, int flags, int err);
1175void sk_stream_kill_queues(struct sock *sk);
1176void sk_set_memalloc(struct sock *sk);
1177void sk_clear_memalloc(struct sock *sk);
1178
1179void __sk_flush_backlog(struct sock *sk);
1180
1181static inline bool sk_flush_backlog(struct sock *sk)
1182{
1183	if (unlikely(READ_ONCE(sk->sk_backlog.tail))) {
1184		__sk_flush_backlog(sk);
1185		return true;
1186	}
1187	return false;
1188}
1189
1190int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb);
1191
1192struct request_sock_ops;
1193struct timewait_sock_ops;
1194struct inet_hashinfo;
1195struct raw_hashinfo;
1196struct smc_hashinfo;
1197struct module;
1198struct sk_psock;
1199
1200/*
1201 * caches using SLAB_TYPESAFE_BY_RCU should let .next pointer from nulls nodes
1202 * un-modified. Special care is taken when initializing object to zero.
1203 */
1204static inline void sk_prot_clear_nulls(struct sock *sk, int size)
1205{
1206	if (offsetof(struct sock, sk_node.next) != 0)
1207		memset(sk, 0, offsetof(struct sock, sk_node.next));
1208	memset(&sk->sk_node.pprev, 0,
1209	       size - offsetof(struct sock, sk_node.pprev));
1210}
1211
1212struct proto_accept_arg {
1213	int flags;
1214	int err;
1215	int is_empty;
1216	bool kern;
1217};
1218
1219/* Networking protocol blocks we attach to sockets.
1220 * socket layer -> transport layer interface
 
1221 */
1222struct proto {
1223	void			(*close)(struct sock *sk,
1224					long timeout);
1225	int			(*pre_connect)(struct sock *sk,
1226					struct sockaddr *uaddr,
1227					int addr_len);
1228	int			(*connect)(struct sock *sk,
1229					struct sockaddr *uaddr,
1230					int addr_len);
1231	int			(*disconnect)(struct sock *sk, int flags);
1232
1233	struct sock *		(*accept)(struct sock *sk,
1234					  struct proto_accept_arg *arg);
1235
1236	int			(*ioctl)(struct sock *sk, int cmd,
1237					 int *karg);
1238	int			(*init)(struct sock *sk);
1239	void			(*destroy)(struct sock *sk);
1240	void			(*shutdown)(struct sock *sk, int how);
1241	int			(*setsockopt)(struct sock *sk, int level,
1242					int optname, sockptr_t optval,
1243					unsigned int optlen);
1244	int			(*getsockopt)(struct sock *sk, int level,
1245					int optname, char __user *optval,
1246					int __user *option);
1247	void			(*keepalive)(struct sock *sk, int valbool);
1248#ifdef CONFIG_COMPAT
 
 
 
 
 
 
 
 
1249	int			(*compat_ioctl)(struct sock *sk,
1250					unsigned int cmd, unsigned long arg);
1251#endif
1252	int			(*sendmsg)(struct sock *sk, struct msghdr *msg,
1253					   size_t len);
1254	int			(*recvmsg)(struct sock *sk, struct msghdr *msg,
1255					   size_t len, int flags, int *addr_len);
1256	void			(*splice_eof)(struct socket *sock);
 
 
 
1257	int			(*bind)(struct sock *sk,
1258					struct sockaddr *addr, int addr_len);
1259	int			(*bind_add)(struct sock *sk,
1260					struct sockaddr *addr, int addr_len);
1261
1262	int			(*backlog_rcv) (struct sock *sk,
1263						struct sk_buff *skb);
1264	bool			(*bpf_bypass_getsockopt)(int level,
1265							 int optname);
1266
1267	void		(*release_cb)(struct sock *sk);
 
1268
1269	/* Keeping track of sk's, looking them up, and port selection methods. */
1270	int			(*hash)(struct sock *sk);
1271	void			(*unhash)(struct sock *sk);
1272	void			(*rehash)(struct sock *sk);
1273	int			(*get_port)(struct sock *sk, unsigned short snum);
1274	void			(*put_port)(struct sock *sk);
1275#ifdef CONFIG_BPF_SYSCALL
1276	int			(*psock_update_sk_prot)(struct sock *sk,
1277							struct sk_psock *psock,
1278							bool restore);
1279#endif
1280
1281	/* Keeping track of sockets in use */
1282#ifdef CONFIG_PROC_FS
1283	unsigned int		inuse_idx;
1284#endif
1285
1286#if IS_ENABLED(CONFIG_MPTCP)
1287	int			(*forward_alloc_get)(const struct sock *sk);
1288#endif
1289
1290	bool			(*stream_memory_free)(const struct sock *sk, int wake);
1291	bool			(*sock_is_readable)(struct sock *sk);
1292	/* Memory pressure */
1293	void			(*enter_memory_pressure)(struct sock *sk);
1294	void			(*leave_memory_pressure)(struct sock *sk);
1295	atomic_long_t		*memory_allocated;	/* Current allocated memory. */
1296	int  __percpu		*per_cpu_fw_alloc;
1297	struct percpu_counter	*sockets_allocated;	/* Current number of sockets. */
1298
1299	/*
1300	 * Pressure flag: try to collapse.
1301	 * Technical note: it is used by multiple contexts non atomically.
1302	 * Make sure to use READ_ONCE()/WRITE_ONCE() for all reads/writes.
1303	 * All the __sk_mem_schedule() is of this nature: accounting
1304	 * is strict, actions are advisory and have some latency.
1305	 */
1306	unsigned long		*memory_pressure;
1307	long			*sysctl_mem;
1308
1309	int			*sysctl_wmem;
1310	int			*sysctl_rmem;
1311	u32			sysctl_wmem_offset;
1312	u32			sysctl_rmem_offset;
1313
1314	int			max_header;
1315	bool			no_autobind;
1316
1317	struct kmem_cache	*slab;
1318	unsigned int		obj_size;
1319	unsigned int		ipv6_pinfo_offset;
1320	slab_flags_t		slab_flags;
1321	unsigned int		useroffset;	/* Usercopy region offset */
1322	unsigned int		usersize;	/* Usercopy region size */
1323
1324	unsigned int __percpu	*orphan_count;
1325
1326	struct request_sock_ops	*rsk_prot;
1327	struct timewait_sock_ops *twsk_prot;
1328
1329	union {
1330		struct inet_hashinfo	*hashinfo;
1331		struct udp_table	*udp_table;
1332		struct raw_hashinfo	*raw_hash;
1333		struct smc_hashinfo	*smc_hash;
1334	} h;
1335
1336	struct module		*owner;
1337
1338	char			name[32];
1339
1340	struct list_head	node;
1341	int			(*diag_destroy)(struct sock *sk, int err);
1342} __randomize_layout;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1343
1344int proto_register(struct proto *prot, int alloc_slab);
1345void proto_unregister(struct proto *prot);
1346int sock_load_diag_module(int family, int protocol);
1347
1348INDIRECT_CALLABLE_DECLARE(bool tcp_stream_memory_free(const struct sock *sk, int wake));
 
 
 
1349
1350static inline int sk_forward_alloc_get(const struct sock *sk)
1351{
1352#if IS_ENABLED(CONFIG_MPTCP)
1353	if (sk->sk_prot->forward_alloc_get)
1354		return sk->sk_prot->forward_alloc_get(sk);
1355#endif
1356	return READ_ONCE(sk->sk_forward_alloc);
1357}
1358
1359static inline bool __sk_stream_memory_free(const struct sock *sk, int wake)
 
1360{
1361	if (READ_ONCE(sk->sk_wmem_queued) >= READ_ONCE(sk->sk_sndbuf))
1362		return false;
1363
1364	return sk->sk_prot->stream_memory_free ?
1365		INDIRECT_CALL_INET_1(sk->sk_prot->stream_memory_free,
1366				     tcp_stream_memory_free, sk, wake) : true;
 
 
 
 
 
 
 
 
 
1367}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1368
1369static inline bool sk_stream_memory_free(const struct sock *sk)
1370{
1371	return __sk_stream_memory_free(sk, 0);
 
 
 
 
1372}
1373
1374static inline bool __sk_stream_is_writeable(const struct sock *sk, int wake)
1375{
1376	return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) &&
1377	       __sk_stream_memory_free(sk, wake);
1378}
1379
1380static inline bool sk_stream_is_writeable(const struct sock *sk)
 
1381{
1382	return __sk_stream_is_writeable(sk, 0);
1383}
1384
1385static inline int sk_under_cgroup_hierarchy(struct sock *sk,
1386					    struct cgroup *ancestor)
1387{
1388#ifdef CONFIG_SOCK_CGROUP_DATA
1389	return cgroup_is_descendant(sock_cgroup_ptr(&sk->sk_cgrp_data),
1390				    ancestor);
1391#else
1392	return -ENOTSUPP;
1393#endif
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1394}
1395
1396#define SK_ALLOC_PERCPU_COUNTER_BATCH 16
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1397
1398static inline void sk_sockets_allocated_dec(struct sock *sk)
1399{
1400	percpu_counter_add_batch(sk->sk_prot->sockets_allocated, -1,
1401				 SK_ALLOC_PERCPU_COUNTER_BATCH);
 
 
 
 
 
 
 
 
1402}
1403
1404static inline void sk_sockets_allocated_inc(struct sock *sk)
1405{
1406	percpu_counter_add_batch(sk->sk_prot->sockets_allocated, 1,
1407				 SK_ALLOC_PERCPU_COUNTER_BATCH);
 
 
 
 
 
 
 
 
1408}
1409
1410static inline u64
1411sk_sockets_allocated_read_positive(struct sock *sk)
1412{
1413	return percpu_counter_read_positive(sk->sk_prot->sockets_allocated);
 
 
 
 
 
1414}
1415
1416static inline int
1417proto_sockets_allocated_sum_positive(struct proto *prot)
1418{
1419	return percpu_counter_sum_positive(prot->sockets_allocated);
1420}
1421
1422#ifdef CONFIG_PROC_FS
1423#define PROTO_INUSE_NR	64	/* should be enough for the first time */
1424struct prot_inuse {
1425	int all;
1426	int val[PROTO_INUSE_NR];
1427};
1428
1429static inline void sock_prot_inuse_add(const struct net *net,
1430				       const struct proto *prot, int val)
1431{
1432	this_cpu_add(net->core.prot_inuse->val[prot->inuse_idx], val);
1433}
1434
1435static inline void sock_inuse_add(const struct net *net, int val)
 
1436{
1437	this_cpu_add(net->core.prot_inuse->all, val);
 
 
1438}
1439
 
 
 
 
1440int sock_prot_inuse_get(struct net *net, struct proto *proto);
1441int sock_inuse_get(struct net *net);
1442#else
1443static inline void sock_prot_inuse_add(const struct net *net,
1444				       const struct proto *prot, int val)
1445{
1446}
1447
1448static inline void sock_inuse_add(const struct net *net, int val)
1449{
1450}
1451#endif
1452
1453
1454/* With per-bucket locks this operation is not-atomic, so that
1455 * this version is not worse.
1456 */
1457static inline int __sk_prot_rehash(struct sock *sk)
1458{
1459	sk->sk_prot->unhash(sk);
1460	return sk->sk_prot->hash(sk);
1461}
1462
 
 
1463/* About 10 seconds */
1464#define SOCK_DESTROY_TIME (10*HZ)
1465
1466/* Sockets 0-1023 can't be bound to unless you are superuser */
1467#define PROT_SOCK	1024
1468
1469#define SHUTDOWN_MASK	3
1470#define RCV_SHUTDOWN	1
1471#define SEND_SHUTDOWN	2
1472
 
 
1473#define SOCK_BINDADDR_LOCK	4
1474#define SOCK_BINDPORT_LOCK	8
1475
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1476struct socket_alloc {
1477	struct socket socket;
1478	struct inode vfs_inode;
1479};
1480
1481static inline struct socket *SOCKET_I(struct inode *inode)
1482{
1483	return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
1484}
1485
1486static inline struct inode *SOCK_INODE(struct socket *socket)
1487{
1488	return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
1489}
1490
1491/*
1492 * Functions for memory accounting
1493 */
1494int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind);
1495int __sk_mem_schedule(struct sock *sk, int size, int kind);
1496void __sk_mem_reduce_allocated(struct sock *sk, int amount);
1497void __sk_mem_reclaim(struct sock *sk, int amount);
1498
 
 
1499#define SK_MEM_SEND	0
1500#define SK_MEM_RECV	1
1501
1502/* sysctl_mem values are in pages */
1503static inline long sk_prot_mem_limits(const struct sock *sk, int index)
1504{
1505	return READ_ONCE(sk->sk_prot->sysctl_mem[index]);
1506}
1507
1508static inline int sk_mem_pages(int amt)
1509{
1510	return (amt + PAGE_SIZE - 1) >> PAGE_SHIFT;
1511}
1512
1513static inline bool sk_has_account(struct sock *sk)
1514{
1515	/* return true if protocol supports memory accounting */
1516	return !!sk->sk_prot->memory_allocated;
1517}
1518
1519static inline bool sk_wmem_schedule(struct sock *sk, int size)
1520{
1521	int delta;
1522
1523	if (!sk_has_account(sk))
1524		return true;
1525	delta = size - sk->sk_forward_alloc;
1526	return delta <= 0 || __sk_mem_schedule(sk, delta, SK_MEM_SEND);
1527}
1528
1529static inline bool
1530__sk_rmem_schedule(struct sock *sk, int size, bool pfmemalloc)
1531{
1532	int delta;
1533
1534	if (!sk_has_account(sk))
1535		return true;
1536	delta = size - sk->sk_forward_alloc;
1537	return delta <= 0 || __sk_mem_schedule(sk, delta, SK_MEM_RECV) ||
1538	       pfmemalloc;
1539}
1540
1541static inline bool
1542sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size)
1543{
1544	return __sk_rmem_schedule(sk, size, skb_pfmemalloc(skb));
1545}
1546
1547static inline int sk_unused_reserved_mem(const struct sock *sk)
1548{
1549	int unused_mem;
1550
1551	if (likely(!sk->sk_reserved_mem))
1552		return 0;
1553
1554	unused_mem = sk->sk_reserved_mem - sk->sk_wmem_queued -
1555			atomic_read(&sk->sk_rmem_alloc);
1556
1557	return unused_mem > 0 ? unused_mem : 0;
1558}
1559
1560static inline void sk_mem_reclaim(struct sock *sk)
1561{
1562	int reclaimable;
1563
1564	if (!sk_has_account(sk))
1565		return;
1566
1567	reclaimable = sk->sk_forward_alloc - sk_unused_reserved_mem(sk);
1568
1569	if (reclaimable >= (int)PAGE_SIZE)
1570		__sk_mem_reclaim(sk, reclaimable);
1571}
1572
1573static inline void sk_mem_reclaim_final(struct sock *sk)
1574{
1575	sk->sk_reserved_mem = 0;
1576	sk_mem_reclaim(sk);
 
 
1577}
1578
1579static inline void sk_mem_charge(struct sock *sk, int size)
1580{
1581	if (!sk_has_account(sk))
1582		return;
1583	sk_forward_alloc_add(sk, -size);
1584}
1585
1586static inline void sk_mem_uncharge(struct sock *sk, int size)
1587{
1588	if (!sk_has_account(sk))
1589		return;
1590	sk_forward_alloc_add(sk, size);
1591	sk_mem_reclaim(sk);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1592}
1593
1594/*
1595 * Macro so as to not evaluate some arguments when
1596 * lockdep is not enabled.
1597 *
1598 * Mark both the sk_lock and the sk_lock.slock as a
1599 * per-address-family lock class.
1600 */
1601#define sock_lock_init_class_and_name(sk, sname, skey, name, key)	\
1602do {									\
1603	sk->sk_lock.owned = 0;						\
1604	init_waitqueue_head(&sk->sk_lock.wq);				\
1605	spin_lock_init(&(sk)->sk_lock.slock);				\
1606	debug_check_no_locks_freed((void *)&(sk)->sk_lock,		\
1607			sizeof((sk)->sk_lock));				\
1608	lockdep_set_class_and_name(&(sk)->sk_lock.slock,		\
1609				(skey), (sname));				\
1610	lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0);	\
1611} while (0)
1612
1613static inline bool lockdep_sock_is_held(const struct sock *sk)
1614{
1615	return lockdep_is_held(&sk->sk_lock) ||
1616	       lockdep_is_held(&sk->sk_lock.slock);
1617}
1618
1619void lock_sock_nested(struct sock *sk, int subclass);
1620
1621static inline void lock_sock(struct sock *sk)
1622{
1623	lock_sock_nested(sk, 0);
1624}
1625
1626void __lock_sock(struct sock *sk);
1627void __release_sock(struct sock *sk);
1628void release_sock(struct sock *sk);
1629
1630/* BH context may only use the following locking interface. */
1631#define bh_lock_sock(__sk)	spin_lock(&((__sk)->sk_lock.slock))
1632#define bh_lock_sock_nested(__sk) \
1633				spin_lock_nested(&((__sk)->sk_lock.slock), \
1634				SINGLE_DEPTH_NESTING)
1635#define bh_unlock_sock(__sk)	spin_unlock(&((__sk)->sk_lock.slock))
1636
1637bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock);
1638
1639/**
1640 * lock_sock_fast - fast version of lock_sock
1641 * @sk: socket
1642 *
1643 * This version should be used for very small section, where process won't block
1644 * return false if fast path is taken:
1645 *
1646 *   sk_lock.slock locked, owned = 0, BH disabled
1647 *
1648 * return true if slow path is taken:
1649 *
1650 *   sk_lock.slock unlocked, owned = 1, BH enabled
1651 */
1652static inline bool lock_sock_fast(struct sock *sk)
1653{
1654	/* The sk_lock has mutex_lock() semantics here. */
1655	mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
1656
1657	return __lock_sock_fast(sk);
1658}
1659
1660/* fast socket lock variant for caller already holding a [different] socket lock */
1661static inline bool lock_sock_fast_nested(struct sock *sk)
1662{
1663	mutex_acquire(&sk->sk_lock.dep_map, SINGLE_DEPTH_NESTING, 0, _RET_IP_);
1664
1665	return __lock_sock_fast(sk);
1666}
1667
1668/**
1669 * unlock_sock_fast - complement of lock_sock_fast
1670 * @sk: socket
1671 * @slow: slow mode
1672 *
1673 * fast unlock socket for user context.
1674 * If slow mode is on, we call regular release_sock()
1675 */
1676static inline void unlock_sock_fast(struct sock *sk, bool slow)
1677	__releases(&sk->sk_lock.slock)
1678{
1679	if (slow) {
1680		release_sock(sk);
1681		__release(&sk->sk_lock.slock);
1682	} else {
1683		mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
1684		spin_unlock_bh(&sk->sk_lock.slock);
1685	}
1686}
1687
1688void sockopt_lock_sock(struct sock *sk);
1689void sockopt_release_sock(struct sock *sk);
1690bool sockopt_ns_capable(struct user_namespace *ns, int cap);
1691bool sockopt_capable(int cap);
1692
1693/* Used by processes to "lock" a socket state, so that
1694 * interrupts and bottom half handlers won't change it
1695 * from under us. It essentially blocks any incoming
1696 * packets, so that we won't get any new data or any
1697 * packets that change the state of the socket.
1698 *
1699 * While locked, BH processing will add new packets to
1700 * the backlog queue.  This queue is processed by the
1701 * owner of the socket lock right before it is released.
1702 *
1703 * Since ~2.3.5 it is also exclusive sleep lock serializing
1704 * accesses from user process context.
1705 */
1706
1707static inline void sock_owned_by_me(const struct sock *sk)
1708{
1709#ifdef CONFIG_LOCKDEP
1710	WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks);
1711#endif
1712}
1713
1714static inline void sock_not_owned_by_me(const struct sock *sk)
1715{
1716#ifdef CONFIG_LOCKDEP
1717	WARN_ON_ONCE(lockdep_sock_is_held(sk) && debug_locks);
1718#endif
1719}
1720
1721static inline bool sock_owned_by_user(const struct sock *sk)
1722{
1723	sock_owned_by_me(sk);
1724	return sk->sk_lock.owned;
1725}
1726
1727static inline bool sock_owned_by_user_nocheck(const struct sock *sk)
1728{
1729	return sk->sk_lock.owned;
1730}
1731
1732static inline void sock_release_ownership(struct sock *sk)
1733{
1734	DEBUG_NET_WARN_ON_ONCE(!sock_owned_by_user_nocheck(sk));
1735	sk->sk_lock.owned = 0;
1736
1737	/* The sk_lock has mutex_unlock() semantics: */
1738	mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
1739}
1740
1741/* no reclassification while locks are held */
1742static inline bool sock_allow_reclassification(const struct sock *csk)
1743{
1744	struct sock *sk = (struct sock *)csk;
1745
1746	return !sock_owned_by_user_nocheck(sk) &&
1747		!spin_is_locked(&sk->sk_lock.slock);
1748}
1749
1750struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1751		      struct proto *prot, int kern);
1752void sk_free(struct sock *sk);
1753void sk_net_refcnt_upgrade(struct sock *sk);
1754void sk_destruct(struct sock *sk);
1755struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority);
1756void sk_free_unlock_clone(struct sock *sk);
1757
1758struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1759			     gfp_t priority);
1760void __sock_wfree(struct sk_buff *skb);
1761void sock_wfree(struct sk_buff *skb);
1762struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
1763			     gfp_t priority);
1764void skb_orphan_partial(struct sk_buff *skb);
1765void sock_rfree(struct sk_buff *skb);
1766void sock_efree(struct sk_buff *skb);
1767#ifdef CONFIG_INET
1768void sock_edemux(struct sk_buff *skb);
1769void sock_pfree(struct sk_buff *skb);
1770
1771static inline void skb_set_owner_edemux(struct sk_buff *skb, struct sock *sk)
1772{
1773	skb_orphan(skb);
1774	if (refcount_inc_not_zero(&sk->sk_refcnt)) {
1775		skb->sk = sk;
1776		skb->destructor = sock_edemux;
1777	}
1778}
1779#else
1780#define sock_edemux sock_efree
1781#endif
1782
1783int sk_setsockopt(struct sock *sk, int level, int optname,
1784		  sockptr_t optval, unsigned int optlen);
1785int sock_setsockopt(struct socket *sock, int level, int op,
1786		    sockptr_t optval, unsigned int optlen);
1787int do_sock_setsockopt(struct socket *sock, bool compat, int level,
1788		       int optname, sockptr_t optval, int optlen);
1789int do_sock_getsockopt(struct socket *sock, bool compat, int level,
1790		       int optname, sockptr_t optval, sockptr_t optlen);
1791
1792int sk_getsockopt(struct sock *sk, int level, int optname,
1793		  sockptr_t optval, sockptr_t optlen);
1794int sock_gettstamp(struct socket *sock, void __user *userstamp,
1795		   bool timeval, bool time32);
1796struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1797				     unsigned long data_len, int noblock,
1798				     int *errcode, int max_page_order);
1799
1800static inline struct sk_buff *sock_alloc_send_skb(struct sock *sk,
1801						  unsigned long size,
1802						  int noblock, int *errcode)
1803{
1804	return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0);
1805}
1806
1807void *sock_kmalloc(struct sock *sk, int size, gfp_t priority);
1808void sock_kfree_s(struct sock *sk, void *mem, int size);
1809void sock_kzfree_s(struct sock *sk, void *mem, int size);
1810void sk_send_sigurg(struct sock *sk);
1811
1812static inline void sock_replace_proto(struct sock *sk, struct proto *proto)
1813{
1814	if (sk->sk_socket)
1815		clear_bit(SOCK_SUPPORT_ZC, &sk->sk_socket->flags);
1816	WRITE_ONCE(sk->sk_prot, proto);
1817}
1818
1819struct sockcm_cookie {
1820	u64 transmit_time;
1821	u32 mark;
1822	u32 tsflags;
1823	u32 ts_opt_id;
1824};
1825
1826static inline void sockcm_init(struct sockcm_cookie *sockc,
1827			       const struct sock *sk)
1828{
1829	*sockc = (struct sockcm_cookie) {
1830		.tsflags = READ_ONCE(sk->sk_tsflags)
1831	};
1832}
1833
1834int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg,
1835		     struct sockcm_cookie *sockc);
1836int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
1837		   struct sockcm_cookie *sockc);
1838
1839/*
1840 * Functions to fill in entries in struct proto_ops when a protocol
1841 * does not implement a particular function.
1842 */
1843int sock_no_bind(struct socket *, struct sockaddr *, int);
1844int sock_no_connect(struct socket *, struct sockaddr *, int, int);
1845int sock_no_socketpair(struct socket *, struct socket *);
1846int sock_no_accept(struct socket *, struct socket *, struct proto_accept_arg *);
1847int sock_no_getname(struct socket *, struct sockaddr *, int);
 
 
1848int sock_no_ioctl(struct socket *, unsigned int, unsigned long);
1849int sock_no_listen(struct socket *, int);
1850int sock_no_shutdown(struct socket *, int);
1851int sock_no_sendmsg(struct socket *, struct msghdr *, size_t);
1852int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len);
1853int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int);
 
 
1854int sock_no_mmap(struct file *file, struct socket *sock,
1855		 struct vm_area_struct *vma);
 
 
1856
1857/*
1858 * Functions to fill in entries in struct proto_ops when a protocol
1859 * uses the inet style.
1860 */
1861int sock_common_getsockopt(struct socket *sock, int level, int optname,
1862				  char __user *optval, int __user *optlen);
1863int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1864			int flags);
1865int sock_common_setsockopt(struct socket *sock, int level, int optname,
1866			   sockptr_t optval, unsigned int optlen);
 
 
 
 
1867
1868void sk_common_release(struct sock *sk);
1869
1870/*
1871 *	Default socket callbacks and setup code
1872 */
1873
1874/* Initialise core socket variables using an explicit uid. */
1875void sock_init_data_uid(struct socket *sock, struct sock *sk, kuid_t uid);
1876
1877/* Initialise core socket variables.
1878 * Assumes struct socket *sock is embedded in a struct socket_alloc.
1879 */
1880void sock_init_data(struct socket *sock, struct sock *sk);
1881
1882/*
1883 * Socket reference counting postulates.
1884 *
1885 * * Each user of socket SHOULD hold a reference count.
1886 * * Each access point to socket (an hash table bucket, reference from a list,
1887 *   running timer, skb in flight MUST hold a reference count.
1888 * * When reference count hits 0, it means it will never increase back.
1889 * * When reference count hits 0, it means that no references from
1890 *   outside exist to this socket and current process on current CPU
1891 *   is last user and may/should destroy this socket.
1892 * * sk_free is called from any context: process, BH, IRQ. When
1893 *   it is called, socket has no references from outside -> sk_free
1894 *   may release descendant resources allocated by the socket, but
1895 *   to the time when it is called, socket is NOT referenced by any
1896 *   hash tables, lists etc.
1897 * * Packets, delivered from outside (from network or from another process)
1898 *   and enqueued on receive/error queues SHOULD NOT grab reference count,
1899 *   when they sit in queue. Otherwise, packets will leak to hole, when
1900 *   socket is looked up by one cpu and unhasing is made by another CPU.
1901 *   It is true for udp/raw, netlink (leak to receive and error queues), tcp
1902 *   (leak to backlog). Packet socket does all the processing inside
1903 *   BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
1904 *   use separate SMP lock, so that they are prone too.
1905 */
1906
1907/* Ungrab socket and destroy it, if it was the last reference. */
1908static inline void sock_put(struct sock *sk)
1909{
1910	if (refcount_dec_and_test(&sk->sk_refcnt))
1911		sk_free(sk);
1912}
1913/* Generic version of sock_put(), dealing with all sockets
1914 * (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...)
1915 */
1916void sock_gen_put(struct sock *sk);
1917
1918int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested,
1919		     unsigned int trim_cap, bool refcounted);
1920static inline int sk_receive_skb(struct sock *sk, struct sk_buff *skb,
1921				 const int nested)
1922{
1923	return __sk_receive_skb(sk, skb, nested, 1, true);
1924}
1925
1926static inline void sk_tx_queue_set(struct sock *sk, int tx_queue)
1927{
1928	/* sk_tx_queue_mapping accept only upto a 16-bit value */
1929	if (WARN_ON_ONCE((unsigned short)tx_queue >= USHRT_MAX))
1930		return;
1931	/* Paired with READ_ONCE() in sk_tx_queue_get() and
1932	 * other WRITE_ONCE() because socket lock might be not held.
1933	 */
1934	WRITE_ONCE(sk->sk_tx_queue_mapping, tx_queue);
1935}
1936
1937#define NO_QUEUE_MAPPING	USHRT_MAX
1938
1939static inline void sk_tx_queue_clear(struct sock *sk)
1940{
1941	/* Paired with READ_ONCE() in sk_tx_queue_get() and
1942	 * other WRITE_ONCE() because socket lock might be not held.
1943	 */
1944	WRITE_ONCE(sk->sk_tx_queue_mapping, NO_QUEUE_MAPPING);
1945}
1946
1947static inline int sk_tx_queue_get(const struct sock *sk)
1948{
1949	if (sk) {
1950		/* Paired with WRITE_ONCE() in sk_tx_queue_clear()
1951		 * and sk_tx_queue_set().
1952		 */
1953		int val = READ_ONCE(sk->sk_tx_queue_mapping);
1954
1955		if (val != NO_QUEUE_MAPPING)
1956			return val;
1957	}
1958	return -1;
1959}
1960
1961static inline void __sk_rx_queue_set(struct sock *sk,
1962				     const struct sk_buff *skb,
1963				     bool force_set)
1964{
1965#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
1966	if (skb_rx_queue_recorded(skb)) {
1967		u16 rx_queue = skb_get_rx_queue(skb);
1968
1969		if (force_set ||
1970		    unlikely(READ_ONCE(sk->sk_rx_queue_mapping) != rx_queue))
1971			WRITE_ONCE(sk->sk_rx_queue_mapping, rx_queue);
1972	}
1973#endif
1974}
1975
1976static inline void sk_rx_queue_set(struct sock *sk, const struct sk_buff *skb)
1977{
1978	__sk_rx_queue_set(sk, skb, true);
1979}
1980
1981static inline void sk_rx_queue_update(struct sock *sk, const struct sk_buff *skb)
1982{
1983	__sk_rx_queue_set(sk, skb, false);
1984}
1985
1986static inline void sk_rx_queue_clear(struct sock *sk)
1987{
1988#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
1989	WRITE_ONCE(sk->sk_rx_queue_mapping, NO_QUEUE_MAPPING);
1990#endif
1991}
1992
1993static inline int sk_rx_queue_get(const struct sock *sk)
1994{
1995#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
1996	if (sk) {
1997		int res = READ_ONCE(sk->sk_rx_queue_mapping);
1998
1999		if (res != NO_QUEUE_MAPPING)
2000			return res;
2001	}
2002#endif
2003
2004	return -1;
2005}
2006
2007static inline void sk_set_socket(struct sock *sk, struct socket *sock)
2008{
 
2009	sk->sk_socket = sock;
2010}
2011
2012static inline wait_queue_head_t *sk_sleep(struct sock *sk)
2013{
2014	BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0);
2015	return &rcu_dereference_raw(sk->sk_wq)->wait;
2016}
2017/* Detach socket from process context.
2018 * Announce socket dead, detach it from wait queue and inode.
2019 * Note that parent inode held reference count on this struct sock,
2020 * we do not release it in this function, because protocol
2021 * probably wants some additional cleanups or even continuing
2022 * to work with this socket (TCP).
2023 */
2024static inline void sock_orphan(struct sock *sk)
2025{
2026	write_lock_bh(&sk->sk_callback_lock);
2027	sock_set_flag(sk, SOCK_DEAD);
2028	sk_set_socket(sk, NULL);
2029	sk->sk_wq  = NULL;
2030	write_unlock_bh(&sk->sk_callback_lock);
2031}
2032
2033static inline void sock_graft(struct sock *sk, struct socket *parent)
2034{
2035	WARN_ON(parent->sk);
2036	write_lock_bh(&sk->sk_callback_lock);
2037	rcu_assign_pointer(sk->sk_wq, &parent->wq);
2038	parent->sk = sk;
2039	sk_set_socket(sk, parent);
2040	sk->sk_uid = SOCK_INODE(parent)->i_uid;
2041	security_sock_graft(sk, parent);
2042	write_unlock_bh(&sk->sk_callback_lock);
2043}
2044
2045kuid_t sock_i_uid(struct sock *sk);
2046unsigned long __sock_i_ino(struct sock *sk);
2047unsigned long sock_i_ino(struct sock *sk);
2048
2049static inline kuid_t sock_net_uid(const struct net *net, const struct sock *sk)
2050{
2051	return sk ? sk->sk_uid : make_kuid(net->user_ns, 0);
2052}
2053
2054static inline u32 net_tx_rndhash(void)
2055{
2056	u32 v = get_random_u32();
2057
2058	return v ?: 1;
2059}
2060
2061static inline void sk_set_txhash(struct sock *sk)
2062{
2063	/* This pairs with READ_ONCE() in skb_set_hash_from_sk() */
2064	WRITE_ONCE(sk->sk_txhash, net_tx_rndhash());
2065}
2066
2067static inline bool sk_rethink_txhash(struct sock *sk)
2068{
2069	if (sk->sk_txhash && sk->sk_txrehash == SOCK_TXREHASH_ENABLED) {
2070		sk_set_txhash(sk);
2071		return true;
2072	}
2073	return false;
2074}
2075
2076static inline struct dst_entry *
2077__sk_dst_get(const struct sock *sk)
2078{
2079	return rcu_dereference_check(sk->sk_dst_cache,
2080				     lockdep_sock_is_held(sk));
2081}
2082
2083static inline struct dst_entry *
2084sk_dst_get(const struct sock *sk)
2085{
2086	struct dst_entry *dst;
2087
2088	rcu_read_lock();
2089	dst = rcu_dereference(sk->sk_dst_cache);
2090	if (dst && !rcuref_get(&dst->__rcuref))
2091		dst = NULL;
2092	rcu_read_unlock();
2093	return dst;
2094}
2095
2096static inline void __dst_negative_advice(struct sock *sk)
2097{
2098	struct dst_entry *dst = __sk_dst_get(sk);
2099
2100	if (dst && dst->ops->negative_advice)
2101		dst->ops->negative_advice(sk, dst);
2102}
2103
2104static inline void dst_negative_advice(struct sock *sk)
2105{
2106	sk_rethink_txhash(sk);
2107	__dst_negative_advice(sk);
 
2108}
2109
2110static inline void
2111__sk_dst_set(struct sock *sk, struct dst_entry *dst)
2112{
2113	struct dst_entry *old_dst;
2114
2115	sk_tx_queue_clear(sk);
2116	WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2117	old_dst = rcu_dereference_protected(sk->sk_dst_cache,
2118					    lockdep_sock_is_held(sk));
 
 
2119	rcu_assign_pointer(sk->sk_dst_cache, dst);
2120	dst_release(old_dst);
2121}
2122
2123static inline void
2124sk_dst_set(struct sock *sk, struct dst_entry *dst)
2125{
2126	struct dst_entry *old_dst;
2127
2128	sk_tx_queue_clear(sk);
2129	WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2130	old_dst = unrcu_pointer(xchg(&sk->sk_dst_cache, RCU_INITIALIZER(dst)));
2131	dst_release(old_dst);
2132}
2133
2134static inline void
2135__sk_dst_reset(struct sock *sk)
2136{
2137	__sk_dst_set(sk, NULL);
2138}
2139
2140static inline void
2141sk_dst_reset(struct sock *sk)
2142{
2143	sk_dst_set(sk, NULL);
 
 
2144}
2145
2146struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
2147
2148struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
2149
2150static inline void sk_dst_confirm(struct sock *sk)
2151{
2152	if (!READ_ONCE(sk->sk_dst_pending_confirm))
2153		WRITE_ONCE(sk->sk_dst_pending_confirm, 1);
2154}
2155
2156static inline void sock_confirm_neigh(struct sk_buff *skb, struct neighbour *n)
2157{
2158	if (skb_get_dst_pending_confirm(skb)) {
2159		struct sock *sk = skb->sk;
2160
2161		if (sk && READ_ONCE(sk->sk_dst_pending_confirm))
2162			WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2163		neigh_confirm(n);
2164	}
2165}
2166
2167bool sk_mc_loop(const struct sock *sk);
2168
2169static inline bool sk_can_gso(const struct sock *sk)
2170{
2171	return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type);
2172}
2173
2174void sk_setup_caps(struct sock *sk, struct dst_entry *dst);
2175
2176static inline void sk_gso_disable(struct sock *sk)
2177{
2178	sk->sk_gso_disabled = 1;
2179	sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2180}
2181
2182static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
2183					   struct iov_iter *from, char *to,
2184					   int copy, int offset)
2185{
2186	if (skb->ip_summed == CHECKSUM_NONE) {
2187		__wsum csum = 0;
2188		if (!csum_and_copy_from_iter_full(to, copy, &csum, from))
2189			return -EFAULT;
 
2190		skb->csum = csum_block_add(skb->csum, csum, offset);
2191	} else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
2192		if (!copy_from_iter_full_nocache(to, copy, from))
 
2193			return -EFAULT;
2194	} else if (!copy_from_iter_full(to, copy, from))
2195		return -EFAULT;
2196
2197	return 0;
2198}
2199
2200static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
2201				       struct iov_iter *from, int copy)
2202{
2203	int err, offset = skb->len;
2204
2205	err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy),
2206				       copy, offset);
2207	if (err)
2208		__skb_trim(skb, offset);
2209
2210	return err;
2211}
2212
2213static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from,
2214					   struct sk_buff *skb,
2215					   struct page *page,
2216					   int off, int copy)
2217{
2218	int err;
2219
2220	err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off,
2221				       copy, skb->len);
2222	if (err)
2223		return err;
2224
2225	skb_len_add(skb, copy);
2226	sk_wmem_queued_add(sk, copy);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2227	sk_mem_charge(sk, copy);
2228	return 0;
2229}
2230
2231/**
2232 * sk_wmem_alloc_get - returns write allocations
2233 * @sk: socket
2234 *
2235 * Return: sk_wmem_alloc minus initial offset of one
2236 */
2237static inline int sk_wmem_alloc_get(const struct sock *sk)
2238{
2239	return refcount_read(&sk->sk_wmem_alloc) - 1;
2240}
2241
2242/**
2243 * sk_rmem_alloc_get - returns read allocations
2244 * @sk: socket
2245 *
2246 * Return: sk_rmem_alloc
2247 */
2248static inline int sk_rmem_alloc_get(const struct sock *sk)
2249{
2250	return atomic_read(&sk->sk_rmem_alloc);
2251}
2252
2253/**
2254 * sk_has_allocations - check if allocations are outstanding
2255 * @sk: socket
2256 *
2257 * Return: true if socket has write or read allocations
2258 */
2259static inline bool sk_has_allocations(const struct sock *sk)
2260{
2261	return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk);
2262}
2263
2264/**
2265 * skwq_has_sleeper - check if there are any waiting processes
2266 * @wq: struct socket_wq
2267 *
2268 * Return: true if socket_wq has waiting processes
2269 *
2270 * The purpose of the skwq_has_sleeper and sock_poll_wait is to wrap the memory
2271 * barrier call. They were added due to the race found within the tcp code.
2272 *
2273 * Consider following tcp code paths::
 
 
2274 *
2275 *   CPU1                CPU2
2276 *   sys_select          receive packet
2277 *   ...                 ...
2278 *   __add_wait_queue    update tp->rcv_nxt
2279 *   ...                 ...
2280 *   tp->rcv_nxt check   sock_def_readable
2281 *   ...                 {
2282 *   schedule               rcu_read_lock();
2283 *                          wq = rcu_dereference(sk->sk_wq);
2284 *                          if (wq && waitqueue_active(&wq->wait))
2285 *                              wake_up_interruptible(&wq->wait)
2286 *                          ...
2287 *                       }
2288 *
2289 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
2290 * in its cache, and so does the tp->rcv_nxt update on CPU2 side.  The CPU1
2291 * could then endup calling schedule and sleep forever if there are no more
2292 * data on the socket.
2293 *
2294 */
2295static inline bool skwq_has_sleeper(struct socket_wq *wq)
2296{
2297	return wq && wq_has_sleeper(&wq->wait);
 
 
 
 
 
 
2298}
2299
2300/**
2301 * sock_poll_wait - wrapper for the poll_wait call.
2302 * @filp:           file
2303 * @sock:           socket to wait on
2304 * @p:              poll_table
2305 *
2306 * See the comments in the wq_has_sleeper function.
2307 */
2308static inline void sock_poll_wait(struct file *filp, struct socket *sock,
2309				  poll_table *p)
2310{
2311	/* Provides a barrier we need to be sure we are in sync
2312	 * with the socket flags modification.
2313	 *
2314	 * This memory barrier is paired in the wq_has_sleeper.
2315	 */
2316	poll_wait(filp, &sock->wq.wait, p);
2317}
2318
2319static inline void skb_set_hash_from_sk(struct sk_buff *skb, struct sock *sk)
2320{
2321	/* This pairs with WRITE_ONCE() in sk_set_txhash() */
2322	u32 txhash = READ_ONCE(sk->sk_txhash);
2323
2324	if (txhash) {
2325		skb->l4_hash = 1;
2326		skb->hash = txhash;
 
 
2327	}
2328}
2329
2330void skb_set_owner_w(struct sk_buff *skb, struct sock *sk);
2331
2332/*
2333 *	Queue a received datagram if it will fit. Stream and sequenced
2334 *	protocols can't normally use this as they need to fit buffers in
2335 *	and play with them.
2336 *
2337 *	Inlined as it's very short and called for pretty much every
2338 *	packet ever received.
2339 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2340static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
2341{
2342	skb_orphan(skb);
2343	skb->sk = sk;
2344	skb->destructor = sock_rfree;
2345	atomic_add(skb->truesize, &sk->sk_rmem_alloc);
2346	sk_mem_charge(sk, skb->truesize);
2347}
2348
2349static inline __must_check bool skb_set_owner_sk_safe(struct sk_buff *skb, struct sock *sk)
2350{
2351	if (sk && refcount_inc_not_zero(&sk->sk_refcnt)) {
2352		skb_orphan(skb);
2353		skb->destructor = sock_efree;
2354		skb->sk = sk;
2355		return true;
2356	}
2357	return false;
2358}
2359
2360static inline struct sk_buff *skb_clone_and_charge_r(struct sk_buff *skb, struct sock *sk)
2361{
2362	skb = skb_clone(skb, sk_gfp_mask(sk, GFP_ATOMIC));
2363	if (skb) {
2364		if (sk_rmem_schedule(sk, skb, skb->truesize)) {
2365			skb_set_owner_r(skb, sk);
2366			return skb;
2367		}
2368		__kfree_skb(skb);
2369	}
2370	return NULL;
2371}
2372
2373static inline void skb_prepare_for_gro(struct sk_buff *skb)
2374{
2375	if (skb->destructor != sock_wfree) {
2376		skb_orphan(skb);
2377		return;
2378	}
2379	skb->slow_gro = 1;
2380}
2381
2382void sk_reset_timer(struct sock *sk, struct timer_list *timer,
2383		    unsigned long expires);
2384
2385void sk_stop_timer(struct sock *sk, struct timer_list *timer);
2386
2387void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer);
2388
2389int __sk_queue_drop_skb(struct sock *sk, struct sk_buff_head *sk_queue,
2390			struct sk_buff *skb, unsigned int flags,
2391			void (*destructor)(struct sock *sk,
2392					   struct sk_buff *skb));
2393int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
2394
2395int sock_queue_rcv_skb_reason(struct sock *sk, struct sk_buff *skb,
2396			      enum skb_drop_reason *reason);
2397
2398static inline int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
2399{
2400	return sock_queue_rcv_skb_reason(sk, skb, NULL);
2401}
2402
2403int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
2404struct sk_buff *sock_dequeue_err_skb(struct sock *sk);
2405
2406/*
2407 *	Recover an error report and clear atomically
2408 */
2409
2410static inline int sock_error(struct sock *sk)
2411{
2412	int err;
2413
2414	/* Avoid an atomic operation for the common case.
2415	 * This is racy since another cpu/thread can change sk_err under us.
2416	 */
2417	if (likely(data_race(!sk->sk_err)))
2418		return 0;
2419
2420	err = xchg(&sk->sk_err, 0);
2421	return -err;
2422}
2423
2424void sk_error_report(struct sock *sk);
2425
2426static inline unsigned long sock_wspace(struct sock *sk)
2427{
2428	int amt = 0;
2429
2430	if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
2431		amt = sk->sk_sndbuf - refcount_read(&sk->sk_wmem_alloc);
2432		if (amt < 0)
2433			amt = 0;
2434	}
2435	return amt;
2436}
2437
2438/* Note:
2439 *  We use sk->sk_wq_raw, from contexts knowing this
2440 *  pointer is not NULL and cannot disappear/change.
2441 */
2442static inline void sk_set_bit(int nr, struct sock *sk)
2443{
2444	if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2445	    !sock_flag(sk, SOCK_FASYNC))
2446		return;
2447
2448	set_bit(nr, &sk->sk_wq_raw->flags);
2449}
2450
2451static inline void sk_clear_bit(int nr, struct sock *sk)
2452{
2453	if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2454	    !sock_flag(sk, SOCK_FASYNC))
2455		return;
2456
2457	clear_bit(nr, &sk->sk_wq_raw->flags);
2458}
2459
2460static inline void sk_wake_async(const struct sock *sk, int how, int band)
2461{
2462	if (sock_flag(sk, SOCK_FASYNC)) {
2463		rcu_read_lock();
2464		sock_wake_async(rcu_dereference(sk->sk_wq), how, band);
2465		rcu_read_unlock();
2466	}
2467}
2468
2469static inline void sk_wake_async_rcu(const struct sock *sk, int how, int band)
2470{
2471	if (unlikely(sock_flag(sk, SOCK_FASYNC)))
2472		sock_wake_async(rcu_dereference(sk->sk_wq), how, band);
2473}
2474
2475/* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might
2476 * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak.
2477 * Note: for send buffers, TCP works better if we can build two skbs at
2478 * minimum.
2479 */
2480#define TCP_SKB_MIN_TRUESIZE	(2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff)))
2481
2482#define SOCK_MIN_SNDBUF		(TCP_SKB_MIN_TRUESIZE * 2)
2483#define SOCK_MIN_RCVBUF		 TCP_SKB_MIN_TRUESIZE
2484
2485static inline void sk_stream_moderate_sndbuf(struct sock *sk)
2486{
2487	u32 val;
2488
2489	if (sk->sk_userlocks & SOCK_SNDBUF_LOCK)
2490		return;
2491
2492	val = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
2493	val = max_t(u32, val, sk_unused_reserved_mem(sk));
2494
2495	WRITE_ONCE(sk->sk_sndbuf, max_t(u32, val, SOCK_MIN_SNDBUF));
2496}
2497
 
 
2498/**
2499 * sk_page_frag - return an appropriate page_frag
2500 * @sk: socket
2501 *
2502 * Use the per task page_frag instead of the per socket one for
2503 * optimization when we know that we're in process context and own
2504 * everything that's associated with %current.
2505 *
2506 * Both direct reclaim and page faults can nest inside other
2507 * socket operations and end up recursing into sk_page_frag()
2508 * while it's already in use: explicitly avoid task page_frag
2509 * when users disable sk_use_task_frag.
2510 *
2511 * Return: a per task page_frag if context allows that,
2512 * otherwise a per socket one.
2513 */
2514static inline struct page_frag *sk_page_frag(struct sock *sk)
2515{
2516	if (sk->sk_use_task_frag)
2517		return &current->task_frag;
2518
2519	return &sk->sk_frag;
2520}
2521
2522bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag);
2523
2524/*
2525 *	Default write policy as shown to user space via poll/select/SIGIO
2526 */
2527static inline bool sock_writeable(const struct sock *sk)
2528{
2529	return refcount_read(&sk->sk_wmem_alloc) < (READ_ONCE(sk->sk_sndbuf) >> 1);
2530}
2531
2532static inline gfp_t gfp_any(void)
2533{
2534	return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2535}
2536
2537static inline gfp_t gfp_memcg_charge(void)
2538{
2539	return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2540}
2541
2542static inline long sock_rcvtimeo(const struct sock *sk, bool noblock)
2543{
2544	return noblock ? 0 : sk->sk_rcvtimeo;
2545}
2546
2547static inline long sock_sndtimeo(const struct sock *sk, bool noblock)
2548{
2549	return noblock ? 0 : sk->sk_sndtimeo;
2550}
2551
2552static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
2553{
2554	int v = waitall ? len : min_t(int, READ_ONCE(sk->sk_rcvlowat), len);
2555
2556	return v ?: 1;
2557}
2558
2559/* Alas, with timeout socket operations are not restartable.
2560 * Compare this to poll().
2561 */
2562static inline int sock_intr_errno(long timeo)
2563{
2564	return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
2565}
2566
2567struct sock_skb_cb {
2568	u32 dropcount;
2569};
2570
2571/* Store sock_skb_cb at the end of skb->cb[] so protocol families
2572 * using skb->cb[] would keep using it directly and utilize its
2573 * alignment guarantee.
2574 */
2575#define SOCK_SKB_CB_OFFSET ((sizeof_field(struct sk_buff, cb) - \
2576			    sizeof(struct sock_skb_cb)))
2577
2578#define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \
2579			    SOCK_SKB_CB_OFFSET))
2580
2581#define sock_skb_cb_check_size(size) \
2582	BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET)
2583
2584static inline void
2585sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb)
2586{
2587	SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, SOCK_RXQ_OVFL) ?
2588						atomic_read(&sk->sk_drops) : 0;
2589}
2590
2591static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb)
2592{
2593	int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs);
2594
2595	atomic_add(segs, &sk->sk_drops);
2596}
2597
2598static inline ktime_t sock_read_timestamp(struct sock *sk)
2599{
2600#if BITS_PER_LONG==32
2601	unsigned int seq;
2602	ktime_t kt;
2603
2604	do {
2605		seq = read_seqbegin(&sk->sk_stamp_seq);
2606		kt = sk->sk_stamp;
2607	} while (read_seqretry(&sk->sk_stamp_seq, seq));
2608
2609	return kt;
2610#else
2611	return READ_ONCE(sk->sk_stamp);
2612#endif
2613}
2614
2615static inline void sock_write_timestamp(struct sock *sk, ktime_t kt)
2616{
2617#if BITS_PER_LONG==32
2618	write_seqlock(&sk->sk_stamp_seq);
2619	sk->sk_stamp = kt;
2620	write_sequnlock(&sk->sk_stamp_seq);
2621#else
2622	WRITE_ONCE(sk->sk_stamp, kt);
2623#endif
2624}
2625
2626void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
2627			   struct sk_buff *skb);
2628void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
2629			     struct sk_buff *skb);
2630
2631static inline void
2632sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
2633{
2634	struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
2635	u32 tsflags = READ_ONCE(sk->sk_tsflags);
2636	ktime_t kt = skb->tstamp;
 
 
2637	/*
2638	 * generate control messages if
2639	 * - receive time stamping in software requested
 
2640	 * - software time stamp available and wanted
 
2641	 * - hardware time stamps available and wanted
 
 
2642	 */
2643	if (sock_flag(sk, SOCK_RCVTSTAMP) ||
2644	    (tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) ||
2645	    (kt && tsflags & SOF_TIMESTAMPING_SOFTWARE) ||
2646	    (hwtstamps->hwtstamp &&
2647	     (tsflags & SOF_TIMESTAMPING_RAW_HARDWARE)))
 
 
2648		__sock_recv_timestamp(msg, sk, skb);
2649	else
2650		sock_write_timestamp(sk, kt);
2651
2652	if (sock_flag(sk, SOCK_WIFI_STATUS) && skb_wifi_acked_valid(skb))
2653		__sock_recv_wifi_status(msg, sk, skb);
2654}
2655
2656void __sock_recv_cmsgs(struct msghdr *msg, struct sock *sk,
2657		       struct sk_buff *skb);
2658
2659#define SK_DEFAULT_STAMP (-1L * NSEC_PER_SEC)
2660static inline void sock_recv_cmsgs(struct msghdr *msg, struct sock *sk,
2661				   struct sk_buff *skb)
2662{
2663#define FLAGS_RECV_CMSGS ((1UL << SOCK_RXQ_OVFL)			| \
2664			   (1UL << SOCK_RCVTSTAMP)			| \
2665			   (1UL << SOCK_RCVMARK))
2666#define TSFLAGS_ANY	  (SOF_TIMESTAMPING_SOFTWARE			| \
2667			   SOF_TIMESTAMPING_RAW_HARDWARE)
2668
2669	if (sk->sk_flags & FLAGS_RECV_CMSGS ||
2670	    READ_ONCE(sk->sk_tsflags) & TSFLAGS_ANY)
2671		__sock_recv_cmsgs(msg, sk, skb);
2672	else if (unlikely(sock_flag(sk, SOCK_TIMESTAMP)))
2673		sock_write_timestamp(sk, skb->tstamp);
2674	else if (unlikely(sock_read_timestamp(sk) == SK_DEFAULT_STAMP))
2675		sock_write_timestamp(sk, 0);
2676}
2677
2678void __sock_tx_timestamp(__u32 tsflags, __u8 *tx_flags);
 
 
 
 
2679
2680/**
2681 * _sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
2682 * @sk:		socket sending this packet
2683 * @sockc:	pointer to socket cmsg cookie to get timestamping info
2684 * @tx_flags:	completed with instructions for time stamping
2685 * @tskey:      filled in with next sk_tskey (not for TCP, which uses seqno)
2686 *
2687 * Note: callers should take care of initial ``*tx_flags`` value (usually 0)
2688 */
2689static inline void _sock_tx_timestamp(struct sock *sk,
2690				      const struct sockcm_cookie *sockc,
2691				      __u8 *tx_flags, __u32 *tskey)
2692{
2693	__u32 tsflags = sockc->tsflags;
2694
2695	if (unlikely(tsflags)) {
2696		__sock_tx_timestamp(tsflags, tx_flags);
2697		if (tsflags & SOF_TIMESTAMPING_OPT_ID && tskey &&
2698		    tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK) {
2699			if (tsflags & SOCKCM_FLAG_TS_OPT_ID)
2700				*tskey = sockc->ts_opt_id;
2701			else
2702				*tskey = atomic_inc_return(&sk->sk_tskey) - 1;
2703		}
2704	}
2705	if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS)))
2706		*tx_flags |= SKBTX_WIFI_STATUS;
2707}
2708
2709static inline void sock_tx_timestamp(struct sock *sk,
2710				     const struct sockcm_cookie *sockc,
2711				     __u8 *tx_flags)
2712{
2713	_sock_tx_timestamp(sk, sockc, tx_flags, NULL);
2714}
2715
2716static inline void skb_setup_tx_timestamp(struct sk_buff *skb,
2717					  const struct sockcm_cookie *sockc)
2718{
2719	_sock_tx_timestamp(skb->sk, sockc, &skb_shinfo(skb)->tx_flags,
2720			   &skb_shinfo(skb)->tskey);
2721}
2722
2723static inline bool sk_is_inet(const struct sock *sk)
2724{
2725	int family = READ_ONCE(sk->sk_family);
2726
2727	return family == AF_INET || family == AF_INET6;
2728}
2729
2730static inline bool sk_is_tcp(const struct sock *sk)
2731{
2732	return sk_is_inet(sk) &&
2733	       sk->sk_type == SOCK_STREAM &&
2734	       sk->sk_protocol == IPPROTO_TCP;
2735}
2736
2737static inline bool sk_is_udp(const struct sock *sk)
2738{
2739	return sk_is_inet(sk) &&
2740	       sk->sk_type == SOCK_DGRAM &&
2741	       sk->sk_protocol == IPPROTO_UDP;
2742}
2743
2744static inline bool sk_is_stream_unix(const struct sock *sk)
2745{
2746	return sk->sk_family == AF_UNIX && sk->sk_type == SOCK_STREAM;
2747}
2748
2749static inline bool sk_is_vsock(const struct sock *sk)
2750{
2751	return sk->sk_family == AF_VSOCK;
2752}
2753
2754/**
2755 * sk_eat_skb - Release a skb if it is no longer needed
2756 * @sk: socket to eat this skb from
2757 * @skb: socket buffer to eat
 
2758 *
2759 * This routine must be called with interrupts disabled or with the socket
2760 * locked so that the sk_buff queue operation is ok.
2761*/
2762static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb)
 
2763{
2764	__skb_unlink(skb, &sk->sk_receive_queue);
2765	__kfree_skb(skb);
 
 
 
2766}
2767
2768static inline bool
2769skb_sk_is_prefetched(struct sk_buff *skb)
2770{
2771#ifdef CONFIG_INET
2772	return skb->destructor == sock_pfree;
2773#else
2774	return false;
2775#endif /* CONFIG_INET */
 
 
2776}
 
2777
2778/* This helper checks if a socket is a full socket,
2779 * ie _not_ a timewait or request socket.
2780 */
2781static inline bool sk_fullsock(const struct sock *sk)
2782{
2783	return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV);
2784}
2785
2786static inline bool
2787sk_is_refcounted(struct sock *sk)
2788{
2789	/* Only full sockets have sk->sk_flags. */
2790	return !sk_fullsock(sk) || !sock_flag(sk, SOCK_RCU_FREE);
2791}
2792
2793/* Checks if this SKB belongs to an HW offloaded socket
2794 * and whether any SW fallbacks are required based on dev.
2795 * Check decrypted mark in case skb_orphan() cleared socket.
 
 
2796 */
2797static inline struct sk_buff *sk_validate_xmit_skb(struct sk_buff *skb,
2798						   struct net_device *dev)
2799{
2800#ifdef CONFIG_SOCK_VALIDATE_XMIT
2801	struct sock *sk = skb->sk;
2802
2803	if (sk && sk_fullsock(sk) && sk->sk_validate_xmit_skb) {
2804		skb = sk->sk_validate_xmit_skb(sk, dev, skb);
2805	} else if (unlikely(skb_is_decrypted(skb))) {
2806		pr_warn_ratelimited("unencrypted skb with no associated socket - dropping\n");
2807		kfree_skb(skb);
2808		skb = NULL;
2809	}
2810#endif
2811
2812	return skb;
2813}
2814
2815/* This helper checks if a socket is a LISTEN or NEW_SYN_RECV
2816 * SYNACK messages can be attached to either ones (depending on SYNCOOKIE)
2817 */
2818static inline bool sk_listener(const struct sock *sk)
2819{
2820	return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV);
2821}
2822
2823/* This helper checks if a socket is a LISTEN or NEW_SYN_RECV or TIME_WAIT
2824 * TCP SYNACK messages can be attached to LISTEN or NEW_SYN_RECV (depending on SYNCOOKIE)
2825 * TCP RST and ACK can be attached to TIME_WAIT.
2826 */
2827static inline bool sk_listener_or_tw(const struct sock *sk)
2828{
2829	return (1 << READ_ONCE(sk->sk_state)) &
2830	       (TCPF_LISTEN | TCPF_NEW_SYN_RECV | TCPF_TIME_WAIT);
2831}
2832
2833void sock_enable_timestamp(struct sock *sk, enum sock_flags flag);
 
 
2834int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level,
2835		       int type);
2836
2837bool sk_ns_capable(const struct sock *sk,
2838		   struct user_namespace *user_ns, int cap);
2839bool sk_capable(const struct sock *sk, int cap);
2840bool sk_net_capable(const struct sock *sk, int cap);
2841
2842void sk_get_meminfo(const struct sock *sk, u32 *meminfo);
 
 
 
 
 
2843
2844/* Take into consideration the size of the struct sk_buff overhead in the
2845 * determination of these values, since that is non-constant across
2846 * platforms.  This makes socket queueing behavior and performance
2847 * not depend upon such differences.
2848 */
2849#define _SK_MEM_PACKETS		256
2850#define _SK_MEM_OVERHEAD	SKB_TRUESIZE(256)
2851#define SK_WMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2852#define SK_RMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2853
2854extern __u32 sysctl_wmem_max;
2855extern __u32 sysctl_rmem_max;
2856
 
 
2857extern __u32 sysctl_wmem_default;
2858extern __u32 sysctl_rmem_default;
2859
2860#define SKB_FRAG_PAGE_ORDER	get_order(32768)
2861DECLARE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
2862
2863static inline int sk_get_wmem0(const struct sock *sk, const struct proto *proto)
2864{
2865	/* Does this proto have per netns sysctl_wmem ? */
2866	if (proto->sysctl_wmem_offset)
2867		return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_wmem_offset));
2868
2869	return READ_ONCE(*proto->sysctl_wmem);
2870}
2871
2872static inline int sk_get_rmem0(const struct sock *sk, const struct proto *proto)
2873{
2874	/* Does this proto have per netns sysctl_rmem ? */
2875	if (proto->sysctl_rmem_offset)
2876		return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_rmem_offset));
2877
2878	return READ_ONCE(*proto->sysctl_rmem);
2879}
2880
2881/* Default TCP Small queue budget is ~1 ms of data (1sec >> 10)
2882 * Some wifi drivers need to tweak it to get more chunks.
2883 * They can use this helper from their ndo_start_xmit()
2884 */
2885static inline void sk_pacing_shift_update(struct sock *sk, int val)
2886{
2887	if (!sk || !sk_fullsock(sk) || READ_ONCE(sk->sk_pacing_shift) == val)
2888		return;
2889	WRITE_ONCE(sk->sk_pacing_shift, val);
2890}
2891
2892/* if a socket is bound to a device, check that the given device
2893 * index is either the same or that the socket is bound to an L3
2894 * master device and the given device index is also enslaved to
2895 * that L3 master
2896 */
2897static inline bool sk_dev_equal_l3scope(struct sock *sk, int dif)
2898{
2899	int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
2900	int mdif;
2901
2902	if (!bound_dev_if || bound_dev_if == dif)
2903		return true;
2904
2905	mdif = l3mdev_master_ifindex_by_index(sock_net(sk), dif);
2906	if (mdif && mdif == bound_dev_if)
2907		return true;
2908
2909	return false;
2910}
2911
2912void sock_def_readable(struct sock *sk);
2913
2914int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk);
2915void sock_set_timestamp(struct sock *sk, int optname, bool valbool);
2916int sock_set_timestamping(struct sock *sk, int optname,
2917			  struct so_timestamping timestamping);
2918
2919void sock_enable_timestamps(struct sock *sk);
2920void sock_no_linger(struct sock *sk);
2921void sock_set_keepalive(struct sock *sk);
2922void sock_set_priority(struct sock *sk, u32 priority);
2923void sock_set_rcvbuf(struct sock *sk, int val);
2924void sock_set_mark(struct sock *sk, u32 val);
2925void sock_set_reuseaddr(struct sock *sk);
2926void sock_set_reuseport(struct sock *sk);
2927void sock_set_sndtimeo(struct sock *sk, s64 secs);
2928
2929int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len);
2930
2931int sock_get_timeout(long timeo, void *optval, bool old_timeval);
2932int sock_copy_user_timeval(struct __kernel_sock_timeval *tv,
2933			   sockptr_t optval, int optlen, bool old_timeval);
2934
2935int sock_ioctl_inout(struct sock *sk, unsigned int cmd,
2936		     void __user *arg, void *karg, size_t size);
2937int sk_ioctl(struct sock *sk, unsigned int cmd, void __user *arg);
2938static inline bool sk_is_readable(struct sock *sk)
2939{
2940	if (sk->sk_prot->sock_is_readable)
2941		return sk->sk_prot->sock_is_readable(sk);
2942	return false;
2943}
2944#endif	/* _SOCK_H */
v3.15
 
   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
 129typedef __u32 __bitwise __portpair;
 130typedef __u64 __bitwise __addrpair;
 131
 132/**
 133 *	struct sock_common - minimal network layer representation of sockets
 134 *	@skc_daddr: Foreign IPv4 addr
 135 *	@skc_rcv_saddr: Bound local IPv4 addr
 
 136 *	@skc_hash: hash value used with various protocol lookup tables
 137 *	@skc_u16hashes: two u16 hash values used by UDP lookup tables
 138 *	@skc_dport: placeholder for inet_dport/tw_dport
 139 *	@skc_num: placeholder for inet_num/tw_num
 
 140 *	@skc_family: network address family
 141 *	@skc_state: Connection state
 142 *	@skc_reuse: %SO_REUSEADDR setting
 143 *	@skc_reuseport: %SO_REUSEPORT setting
 
 
 144 *	@skc_bound_dev_if: bound device index if != 0
 145 *	@skc_bind_node: bind hash linkage for various protocol lookup tables
 146 *	@skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol
 147 *	@skc_prot: protocol handlers inside a network family
 148 *	@skc_net: reference to the network namespace of this socket
 
 
 
 149 *	@skc_node: main hash linkage for various protocol lookup tables
 150 *	@skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol
 151 *	@skc_tx_queue_mapping: tx queue number for this connection
 
 
 
 
 
 
 
 
 
 
 
 
 
 152 *	@skc_refcnt: reference count
 153 *
 154 *	This is the minimal network layer representation of sockets, the header
 155 *	for struct sock and struct inet_timewait_sock.
 156 */
 157struct sock_common {
 158	/* skc_daddr and skc_rcv_saddr must be grouped on a 8 bytes aligned
 159	 * address on 64bit arches : cf INET_MATCH()
 160	 */
 161	union {
 162		__addrpair	skc_addrpair;
 163		struct {
 164			__be32	skc_daddr;
 165			__be32	skc_rcv_saddr;
 166		};
 167	};
 168	union  {
 169		unsigned int	skc_hash;
 170		__u16		skc_u16hashes[2];
 171	};
 172	/* skc_dport && skc_num must be grouped as well */
 173	union {
 174		__portpair	skc_portpair;
 175		struct {
 176			__be16	skc_dport;
 177			__u16	skc_num;
 178		};
 179	};
 180
 181	unsigned short		skc_family;
 182	volatile unsigned char	skc_state;
 183	unsigned char		skc_reuse:4;
 184	unsigned char		skc_reuseport:4;
 
 
 185	int			skc_bound_dev_if;
 186	union {
 187		struct hlist_node	skc_bind_node;
 188		struct hlist_nulls_node skc_portaddr_node;
 189	};
 190	struct proto		*skc_prot;
 191#ifdef CONFIG_NET_NS
 192	struct net	 	*skc_net;
 193#endif
 194
 195#if IS_ENABLED(CONFIG_IPV6)
 196	struct in6_addr		skc_v6_daddr;
 197	struct in6_addr		skc_v6_rcv_saddr;
 198#endif
 199
 
 
 
 
 
 
 
 
 
 
 
 
 200	/*
 201	 * fields between dontcopy_begin/dontcopy_end
 202	 * are not copied in sock_copy()
 203	 */
 204	/* private: */
 205	int			skc_dontcopy_begin[0];
 206	/* public: */
 207	union {
 208		struct hlist_node	skc_node;
 209		struct hlist_nulls_node skc_nulls_node;
 210	};
 211	int			skc_tx_queue_mapping;
 212	atomic_t		skc_refcnt;
 
 
 
 
 
 
 
 
 
 213	/* private: */
 214	int                     skc_dontcopy_end[0];
 
 
 
 
 
 215	/* public: */
 216};
 217
 218struct cg_proto;
 
 
 219/**
 220  *	struct sock - network layer representation of sockets
 221  *	@__sk_common: shared layout with inet_timewait_sock
 222  *	@sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
 223  *	@sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
 224  *	@sk_lock:	synchronizer
 
 225  *	@sk_rcvbuf: size of receive buffer in bytes
 226  *	@sk_wq: sock wait queue and async head
 227  *	@sk_rx_dst: receive input route used by early demux
 
 
 228  *	@sk_dst_cache: destination cache
 229  *	@sk_dst_lock: destination cache lock
 230  *	@sk_policy: flow policy
 231  *	@sk_receive_queue: incoming packets
 232  *	@sk_wmem_alloc: transmit queue bytes committed
 
 233  *	@sk_write_queue: Packet sending queue
 234  *	@sk_async_wait_queue: DMA copied packets
 235  *	@sk_omem_alloc: "o" is "option" or "other"
 236  *	@sk_wmem_queued: persistent queue size
 237  *	@sk_forward_alloc: space allocated forward
 
 238  *	@sk_napi_id: id of the last napi context to receive data for sk
 239  *	@sk_ll_usec: usecs to busypoll when there is no data
 240  *	@sk_allocation: allocation mode
 241  *	@sk_pacing_rate: Pacing rate (if supported by transport/packet scheduler)
 
 242  *	@sk_max_pacing_rate: Maximum pacing rate (%SO_MAX_PACING_RATE)
 243  *	@sk_sndbuf: size of send buffer in bytes
 244  *	@sk_flags: %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE,
 245  *		   %SO_OOBINLINE settings, %SO_TIMESTAMPING settings
 246  *	@sk_no_check: %SO_NO_CHECK setting, whether or not checkup packets
 247  *	@sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
 248  *	@sk_route_nocaps: forbidden route capabilities (e.g NETIF_F_GSO_MASK)
 249  *	@sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
 250  *	@sk_gso_max_size: Maximum GSO segment size to build
 251  *	@sk_gso_max_segs: Maximum number of GSO segments
 
 252  *	@sk_lingertime: %SO_LINGER l_linger setting
 253  *	@sk_backlog: always used with the per-socket spinlock held
 254  *	@sk_callback_lock: used with the callbacks in the end of this struct
 255  *	@sk_error_queue: rarely used
 256  *	@sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt,
 257  *			  IPV6_ADDRFORM for instance)
 258  *	@sk_err: last error
 259  *	@sk_err_soft: errors that don't cause failure but are the cause of a
 260  *		      persistent failure not just 'timed out'
 261  *	@sk_drops: raw/udp drops counter
 262  *	@sk_ack_backlog: current listen backlog
 263  *	@sk_max_ack_backlog: listen backlog set in listen()
 
 
 
 264  *	@sk_priority: %SO_PRIORITY setting
 265  *	@sk_cgrp_prioidx: socket group's priority map index
 266  *	@sk_type: socket type (%SOCK_STREAM, etc)
 267  *	@sk_protocol: which protocol this socket belongs in this network family
 
 268  *	@sk_peer_pid: &struct pid for this socket's peer
 269  *	@sk_peer_cred: %SO_PEERCRED setting
 270  *	@sk_rcvlowat: %SO_RCVLOWAT setting
 271  *	@sk_rcvtimeo: %SO_RCVTIMEO setting
 272  *	@sk_sndtimeo: %SO_SNDTIMEO setting
 273  *	@sk_rxhash: flow hash received from netif layer
 
 274  *	@sk_filter: socket filtering instructions
 275  *	@sk_protinfo: private area, net family specific, when not using slab
 276  *	@sk_timer: sock cleanup timer
 277  *	@sk_stamp: time stamp of last packet received
 
 
 
 
 
 
 
 
 
 278  *	@sk_socket: Identd and reporting IO signals
 279  *	@sk_user_data: RPC layer private data
 280  *	@sk_frag: cached page frag
 281  *	@sk_peek_off: current peek_offset value
 282  *	@sk_send_head: front of stuff to transmit
 
 283  *	@sk_security: used by security modules
 284  *	@sk_mark: generic packet mark
 285  *	@sk_classid: this socket's cgroup classid
 286  *	@sk_cgrp: this socket's cgroup-specific proto data
 287  *	@sk_write_pending: a write to stream socket waits to start
 
 288  *	@sk_state_change: callback to indicate change in the state of the sock
 289  *	@sk_data_ready: callback to indicate there is data to be processed
 290  *	@sk_write_space: callback to indicate there is bf sending space available
 291  *	@sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
 292  *	@sk_backlog_rcv: callback to process the backlog
 
 293  *	@sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
 294 */
 
 
 
 
 
 
 
 
 
 295struct sock {
 296	/*
 297	 * Now struct inet_timewait_sock also uses sock_common, so please just
 298	 * don't add nothing before this first member (__sk_common) --acme
 299	 */
 300	struct sock_common	__sk_common;
 301#define sk_node			__sk_common.skc_node
 302#define sk_nulls_node		__sk_common.skc_nulls_node
 303#define sk_refcnt		__sk_common.skc_refcnt
 304#define sk_tx_queue_mapping	__sk_common.skc_tx_queue_mapping
 
 
 
 305
 306#define sk_dontcopy_begin	__sk_common.skc_dontcopy_begin
 307#define sk_dontcopy_end		__sk_common.skc_dontcopy_end
 308#define sk_hash			__sk_common.skc_hash
 309#define sk_portpair		__sk_common.skc_portpair
 310#define sk_num			__sk_common.skc_num
 311#define sk_dport		__sk_common.skc_dport
 312#define sk_addrpair		__sk_common.skc_addrpair
 313#define sk_daddr		__sk_common.skc_daddr
 314#define sk_rcv_saddr		__sk_common.skc_rcv_saddr
 315#define sk_family		__sk_common.skc_family
 316#define sk_state		__sk_common.skc_state
 317#define sk_reuse		__sk_common.skc_reuse
 318#define sk_reuseport		__sk_common.skc_reuseport
 
 
 319#define sk_bound_dev_if		__sk_common.skc_bound_dev_if
 320#define sk_bind_node		__sk_common.skc_bind_node
 321#define sk_prot			__sk_common.skc_prot
 322#define sk_net			__sk_common.skc_net
 323#define sk_v6_daddr		__sk_common.skc_v6_daddr
 324#define sk_v6_rcv_saddr	__sk_common.skc_v6_rcv_saddr
 
 
 
 
 
 
 325
 326	socket_lock_t		sk_lock;
 
 
 327	struct sk_buff_head	sk_receive_queue;
 328	/*
 329	 * The backlog queue is special, it is always used with
 330	 * the per-socket spinlock held and requires low latency
 331	 * access. Therefore we special case it's implementation.
 332	 * Note : rmem_alloc is in this structure to fill a hole
 333	 * on 64bit arches, not because its logically part of
 334	 * backlog.
 335	 */
 336	struct {
 337		atomic_t	rmem_alloc;
 338		int		len;
 339		struct sk_buff	*head;
 340		struct sk_buff	*tail;
 341	} sk_backlog;
 342#define sk_rmem_alloc sk_backlog.rmem_alloc
 343	int			sk_forward_alloc;
 344#ifdef CONFIG_RPS
 345	__u32			sk_rxhash;
 346#endif
 
 
 
 
 
 347#ifdef CONFIG_NET_RX_BUSY_POLL
 
 348	unsigned int		sk_napi_id;
 349	unsigned int		sk_ll_usec;
 
 350#endif
 351	atomic_t		sk_drops;
 352	int			sk_rcvbuf;
 353
 354	struct sk_filter __rcu	*sk_filter;
 355	struct socket_wq __rcu	*sk_wq;
 
 
 
 
 
 356
 357#ifdef CONFIG_NET_DMA
 358	struct sk_buff_head	sk_async_wait_queue;
 359#endif
 
 360
 
 
 
 
 361#ifdef CONFIG_XFRM
 362	struct xfrm_policy	*sk_policy[2];
 363#endif
 364	unsigned long 		sk_flags;
 365	struct dst_entry	*sk_rx_dst;
 366	struct dst_entry __rcu	*sk_dst_cache;
 367	spinlock_t		sk_dst_lock;
 368	atomic_t		sk_wmem_alloc;
 
 
 
 
 
 
 369	atomic_t		sk_omem_alloc;
 370	int			sk_sndbuf;
 
 
 
 
 
 
 
 
 371	struct sk_buff_head	sk_write_queue;
 372	kmemcheck_bitfield_begin(flags);
 373	unsigned int		sk_shutdown  : 2,
 374				sk_no_check  : 2,
 375				sk_userlocks : 4,
 376				sk_protocol  : 8,
 377				sk_type      : 16;
 378	kmemcheck_bitfield_end(flags);
 379	int			sk_wmem_queued;
 380	gfp_t			sk_allocation;
 381	u32			sk_pacing_rate; /* bytes per second */
 382	u32			sk_max_pacing_rate;
 
 
 
 
 
 383	netdev_features_t	sk_route_caps;
 384	netdev_features_t	sk_route_nocaps;
 385	int			sk_gso_type;
 
 
 
 
 
 386	unsigned int		sk_gso_max_size;
 387	u16			sk_gso_max_segs;
 388	int			sk_rcvlowat;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 389	unsigned long	        sk_lingertime;
 390	struct sk_buff_head	sk_error_queue;
 391	struct proto		*sk_prot_creator;
 392	rwlock_t		sk_callback_lock;
 393	int			sk_err,
 394				sk_err_soft;
 395	unsigned short		sk_ack_backlog;
 396	unsigned short		sk_max_ack_backlog;
 397	__u32			sk_priority;
 398#if IS_ENABLED(CONFIG_CGROUP_NET_PRIO)
 399	__u32			sk_cgrp_prioidx;
 400#endif
 401	struct pid		*sk_peer_pid;
 402	const struct cred	*sk_peer_cred;
 403	long			sk_rcvtimeo;
 404	long			sk_sndtimeo;
 405	void			*sk_protinfo;
 406	struct timer_list	sk_timer;
 407	ktime_t			sk_stamp;
 408	struct socket		*sk_socket;
 
 
 
 
 
 
 
 
 
 
 409	void			*sk_user_data;
 410	struct page_frag	sk_frag;
 411	struct sk_buff		*sk_send_head;
 412	__s32			sk_peek_off;
 413	int			sk_write_pending;
 414#ifdef CONFIG_SECURITY
 415	void			*sk_security;
 416#endif
 417	__u32			sk_mark;
 418	u32			sk_classid;
 419	struct cg_proto		*sk_cgrp;
 420	void			(*sk_state_change)(struct sock *sk);
 421	void			(*sk_data_ready)(struct sock *sk);
 422	void			(*sk_write_space)(struct sock *sk);
 423	void			(*sk_error_report)(struct sock *sk);
 424	int			(*sk_backlog_rcv)(struct sock *sk,
 425						  struct sk_buff *skb);
 426	void                    (*sk_destruct)(struct sock *sk);
 
 
 
 
 
 
 
 
 
 
 
 
 427};
 428
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 429#define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data)))
 430
 431#define rcu_dereference_sk_user_data(sk)	rcu_dereference(__sk_user_data((sk)))
 432#define rcu_assign_sk_user_data(sk, ptr)	rcu_assign_pointer(__sk_user_data((sk)), ptr)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 433
 434/*
 435 * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK
 436 * or not whether his port will be reused by someone else. SK_FORCE_REUSE
 437 * on a socket means that the socket will reuse everybody else's port
 438 * without looking at the other's sk_reuse value.
 439 */
 440
 441#define SK_NO_REUSE	0
 442#define SK_CAN_REUSE	1
 443#define SK_FORCE_REUSE	2
 444
 445static inline int sk_peek_offset(struct sock *sk, int flags)
 
 
 446{
 447	if ((flags & MSG_PEEK) && (sk->sk_peek_off >= 0))
 448		return sk->sk_peek_off;
 449	else
 450		return 0;
 
 451}
 452
 453static inline void sk_peek_offset_bwd(struct sock *sk, int val)
 454{
 455	if (sk->sk_peek_off >= 0) {
 456		if (sk->sk_peek_off >= val)
 457			sk->sk_peek_off -= val;
 458		else
 459			sk->sk_peek_off = 0;
 460	}
 461}
 462
 463static inline void sk_peek_offset_fwd(struct sock *sk, int val)
 464{
 465	if (sk->sk_peek_off >= 0)
 466		sk->sk_peek_off += val;
 467}
 468
 469/*
 470 * Hashed lists helper routines
 471 */
 472static inline struct sock *sk_entry(const struct hlist_node *node)
 473{
 474	return hlist_entry(node, struct sock, sk_node);
 475}
 476
 477static inline struct sock *__sk_head(const struct hlist_head *head)
 478{
 479	return hlist_entry(head->first, struct sock, sk_node);
 480}
 481
 482static inline struct sock *sk_head(const struct hlist_head *head)
 483{
 484	return hlist_empty(head) ? NULL : __sk_head(head);
 485}
 486
 487static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head)
 488{
 489	return hlist_nulls_entry(head->first, struct sock, sk_nulls_node);
 490}
 491
 492static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head)
 493{
 494	return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head);
 495}
 496
 497static inline struct sock *sk_next(const struct sock *sk)
 498{
 499	return sk->sk_node.next ?
 500		hlist_entry(sk->sk_node.next, struct sock, sk_node) : NULL;
 501}
 502
 503static inline struct sock *sk_nulls_next(const struct sock *sk)
 504{
 505	return (!is_a_nulls(sk->sk_nulls_node.next)) ?
 506		hlist_nulls_entry(sk->sk_nulls_node.next,
 507				  struct sock, sk_nulls_node) :
 508		NULL;
 509}
 510
 511static inline bool sk_unhashed(const struct sock *sk)
 512{
 513	return hlist_unhashed(&sk->sk_node);
 514}
 515
 516static inline bool sk_hashed(const struct sock *sk)
 517{
 518	return !sk_unhashed(sk);
 519}
 520
 521static inline void sk_node_init(struct hlist_node *node)
 522{
 523	node->pprev = NULL;
 524}
 525
 526static inline void sk_nulls_node_init(struct hlist_nulls_node *node)
 527{
 528	node->pprev = NULL;
 529}
 530
 531static inline void __sk_del_node(struct sock *sk)
 532{
 533	__hlist_del(&sk->sk_node);
 534}
 535
 536/* NB: equivalent to hlist_del_init_rcu */
 537static inline bool __sk_del_node_init(struct sock *sk)
 538{
 539	if (sk_hashed(sk)) {
 540		__sk_del_node(sk);
 541		sk_node_init(&sk->sk_node);
 542		return true;
 543	}
 544	return false;
 545}
 546
 547/* Grab socket reference count. This operation is valid only
 548   when sk is ALREADY grabbed f.e. it is found in hash table
 549   or a list and the lookup is made under lock preventing hash table
 550   modifications.
 551 */
 552
 553static inline void sock_hold(struct sock *sk)
 554{
 555	atomic_inc(&sk->sk_refcnt);
 556}
 557
 558/* Ungrab socket in the context, which assumes that socket refcnt
 559   cannot hit zero, f.e. it is true in context of any socketcall.
 560 */
 561static inline void __sock_put(struct sock *sk)
 562{
 563	atomic_dec(&sk->sk_refcnt);
 564}
 565
 566static inline bool sk_del_node_init(struct sock *sk)
 567{
 568	bool rc = __sk_del_node_init(sk);
 569
 570	if (rc) {
 571		/* paranoid for a while -acme */
 572		WARN_ON(atomic_read(&sk->sk_refcnt) == 1);
 573		__sock_put(sk);
 574	}
 575	return rc;
 576}
 577#define sk_del_node_init_rcu(sk)	sk_del_node_init(sk)
 578
 579static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk)
 580{
 581	if (sk_hashed(sk)) {
 582		hlist_nulls_del_init_rcu(&sk->sk_nulls_node);
 583		return true;
 584	}
 585	return false;
 586}
 587
 588static inline bool sk_nulls_del_node_init_rcu(struct sock *sk)
 589{
 590	bool rc = __sk_nulls_del_node_init_rcu(sk);
 591
 592	if (rc) {
 593		/* paranoid for a while -acme */
 594		WARN_ON(atomic_read(&sk->sk_refcnt) == 1);
 595		__sock_put(sk);
 596	}
 597	return rc;
 598}
 599
 600static inline void __sk_add_node(struct sock *sk, struct hlist_head *list)
 601{
 602	hlist_add_head(&sk->sk_node, list);
 603}
 604
 605static inline void sk_add_node(struct sock *sk, struct hlist_head *list)
 606{
 607	sock_hold(sk);
 608	__sk_add_node(sk, list);
 609}
 610
 611static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list)
 612{
 613	sock_hold(sk);
 614	hlist_add_head_rcu(&sk->sk_node, list);
 
 
 
 
 
 
 
 
 
 
 615}
 616
 617static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
 618{
 619	hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list);
 620}
 621
 
 
 
 
 
 622static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
 623{
 624	sock_hold(sk);
 625	__sk_nulls_add_node_rcu(sk, list);
 626}
 627
 628static inline void __sk_del_bind_node(struct sock *sk)
 629{
 630	__hlist_del(&sk->sk_bind_node);
 631}
 632
 633static inline void sk_add_bind_node(struct sock *sk,
 634					struct hlist_head *list)
 635{
 636	hlist_add_head(&sk->sk_bind_node, list);
 637}
 638
 639#define sk_for_each(__sk, list) \
 640	hlist_for_each_entry(__sk, list, sk_node)
 641#define sk_for_each_rcu(__sk, list) \
 642	hlist_for_each_entry_rcu(__sk, list, sk_node)
 643#define sk_nulls_for_each(__sk, node, list) \
 644	hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)
 645#define sk_nulls_for_each_rcu(__sk, node, list) \
 646	hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)
 647#define sk_for_each_from(__sk) \
 648	hlist_for_each_entry_from(__sk, sk_node)
 649#define sk_nulls_for_each_from(__sk, node) \
 650	if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \
 651		hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node)
 652#define sk_for_each_safe(__sk, tmp, list) \
 653	hlist_for_each_entry_safe(__sk, tmp, list, sk_node)
 654#define sk_for_each_bound(__sk, list) \
 655	hlist_for_each_entry(__sk, list, sk_bind_node)
 
 
 656
 657static inline struct user_namespace *sk_user_ns(struct sock *sk)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 658{
 659	/* Careful only use this in a context where these parameters
 660	 * can not change and must all be valid, such as recvmsg from
 661	 * userspace.
 662	 */
 663	return sk->sk_socket->file->f_cred->user_ns;
 664}
 665
 666/* Sock flags */
 667enum sock_flags {
 668	SOCK_DEAD,
 669	SOCK_DONE,
 670	SOCK_URGINLINE,
 671	SOCK_KEEPOPEN,
 672	SOCK_LINGER,
 673	SOCK_DESTROY,
 674	SOCK_BROADCAST,
 675	SOCK_TIMESTAMP,
 676	SOCK_ZAPPED,
 677	SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */
 678	SOCK_DBG, /* %SO_DEBUG setting */
 679	SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
 680	SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */
 681	SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
 682	SOCK_QUEUE_SHRUNK, /* write queue has been shrunk recently */
 683	SOCK_MEMALLOC, /* VM depends on this socket for swapping */
 684	SOCK_TIMESTAMPING_TX_HARDWARE,  /* %SOF_TIMESTAMPING_TX_HARDWARE */
 685	SOCK_TIMESTAMPING_TX_SOFTWARE,  /* %SOF_TIMESTAMPING_TX_SOFTWARE */
 686	SOCK_TIMESTAMPING_RX_HARDWARE,  /* %SOF_TIMESTAMPING_RX_HARDWARE */
 687	SOCK_TIMESTAMPING_RX_SOFTWARE,  /* %SOF_TIMESTAMPING_RX_SOFTWARE */
 688	SOCK_TIMESTAMPING_SOFTWARE,     /* %SOF_TIMESTAMPING_SOFTWARE */
 689	SOCK_TIMESTAMPING_RAW_HARDWARE, /* %SOF_TIMESTAMPING_RAW_HARDWARE */
 690	SOCK_TIMESTAMPING_SYS_HARDWARE, /* %SOF_TIMESTAMPING_SYS_HARDWARE */
 691	SOCK_FASYNC, /* fasync() active */
 692	SOCK_RXQ_OVFL,
 693	SOCK_ZEROCOPY, /* buffers from userspace */
 694	SOCK_WIFI_STATUS, /* push wifi status to userspace */
 695	SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS.
 696		     * Will use last 4 bytes of packet sent from
 697		     * user-space instead.
 698		     */
 699	SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */
 700	SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */
 
 
 
 
 
 701};
 702
 703static inline void sock_copy_flags(struct sock *nsk, struct sock *osk)
 
 
 
 
 
 
 
 
 704{
 705	nsk->sk_flags = osk->sk_flags;
 706}
 707
 708static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
 709{
 710	__set_bit(flag, &sk->sk_flags);
 711}
 712
 713static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag)
 714{
 715	__clear_bit(flag, &sk->sk_flags);
 716}
 717
 
 
 
 
 
 
 
 
 
 718static inline bool sock_flag(const struct sock *sk, enum sock_flags flag)
 719{
 720	return test_bit(flag, &sk->sk_flags);
 721}
 722
 723#ifdef CONFIG_NET
 724extern struct static_key memalloc_socks;
 725static inline int sk_memalloc_socks(void)
 726{
 727	return static_key_false(&memalloc_socks);
 728}
 
 
 729#else
 730
 731static inline int sk_memalloc_socks(void)
 732{
 733	return 0;
 734}
 735
 
 
 736#endif
 737
 738static inline gfp_t sk_gfp_atomic(struct sock *sk, gfp_t gfp_mask)
 739{
 740	return GFP_ATOMIC | (sk->sk_allocation & __GFP_MEMALLOC);
 741}
 742
 743static inline void sk_acceptq_removed(struct sock *sk)
 744{
 745	sk->sk_ack_backlog--;
 746}
 747
 748static inline void sk_acceptq_added(struct sock *sk)
 749{
 750	sk->sk_ack_backlog++;
 751}
 752
 
 
 
 
 753static inline bool sk_acceptq_is_full(const struct sock *sk)
 754{
 755	return sk->sk_ack_backlog > sk->sk_max_ack_backlog;
 756}
 757
 758/*
 759 * Compute minimal free write space needed to queue new packets.
 760 */
 761static inline int sk_stream_min_wspace(const struct sock *sk)
 762{
 763	return sk->sk_wmem_queued >> 1;
 764}
 765
 766static inline int sk_stream_wspace(const struct sock *sk)
 767{
 768	return sk->sk_sndbuf - sk->sk_wmem_queued;
 
 
 
 
 
 
 
 
 
 
 
 769}
 770
 771void sk_stream_write_space(struct sock *sk);
 772
 773/* OOB backlog add */
 774static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
 775{
 776	/* dont let skb dst not refcounted, we are going to leave rcu lock */
 777	skb_dst_force(skb);
 778
 779	if (!sk->sk_backlog.tail)
 780		sk->sk_backlog.head = skb;
 781	else
 782		sk->sk_backlog.tail->next = skb;
 783
 784	sk->sk_backlog.tail = skb;
 785	skb->next = NULL;
 786}
 787
 788/*
 789 * Take into account size of receive queue and backlog queue
 790 * Do not take into account this skb truesize,
 791 * to allow even a single big packet to come.
 792 */
 793static inline bool sk_rcvqueues_full(const struct sock *sk, const struct sk_buff *skb,
 794				     unsigned int limit)
 795{
 796	unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc);
 797
 798	return qsize > limit;
 799}
 800
 801/* The per-socket spinlock must be held here. */
 802static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb,
 803					      unsigned int limit)
 804{
 805	if (sk_rcvqueues_full(sk, skb, limit))
 806		return -ENOBUFS;
 807
 
 
 
 
 
 
 
 
 808	__sk_add_backlog(sk, skb);
 809	sk->sk_backlog.len += skb->truesize;
 810	return 0;
 811}
 812
 813int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb);
 814
 
 
 
 815static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
 816{
 817	if (sk_memalloc_socks() && skb_pfmemalloc(skb))
 818		return __sk_backlog_rcv(sk, skb);
 819
 820	return sk->sk_backlog_rcv(sk, skb);
 821}
 822
 823static inline void sock_rps_record_flow_hash(__u32 hash)
 824{
 825#ifdef CONFIG_RPS
 826	struct rps_sock_flow_table *sock_flow_table;
 827
 828	rcu_read_lock();
 829	sock_flow_table = rcu_dereference(rps_sock_flow_table);
 830	rps_record_sock_flow(sock_flow_table, hash);
 831	rcu_read_unlock();
 832#endif
 833}
 834
 835static inline void sock_rps_reset_flow_hash(__u32 hash)
 836{
 837#ifdef CONFIG_RPS
 838	struct rps_sock_flow_table *sock_flow_table;
 839
 840	rcu_read_lock();
 841	sock_flow_table = rcu_dereference(rps_sock_flow_table);
 842	rps_reset_sock_flow(sock_flow_table, hash);
 843	rcu_read_unlock();
 844#endif
 845}
 846
 847static inline void sock_rps_record_flow(const struct sock *sk)
 848{
 849#ifdef CONFIG_RPS
 850	sock_rps_record_flow_hash(sk->sk_rxhash);
 851#endif
 852}
 853
 854static inline void sock_rps_reset_flow(const struct sock *sk)
 855{
 856#ifdef CONFIG_RPS
 857	sock_rps_reset_flow_hash(sk->sk_rxhash);
 858#endif
 859}
 860
 861static inline void sock_rps_save_rxhash(struct sock *sk,
 862					const struct sk_buff *skb)
 863{
 864#ifdef CONFIG_RPS
 865	if (unlikely(sk->sk_rxhash != skb->hash)) {
 866		sock_rps_reset_flow(sk);
 867		sk->sk_rxhash = skb->hash;
 868	}
 
 869#endif
 870}
 871
 872static inline void sock_rps_reset_rxhash(struct sock *sk)
 873{
 874#ifdef CONFIG_RPS
 875	sock_rps_reset_flow(sk);
 876	sk->sk_rxhash = 0;
 877#endif
 878}
 879
 880#define sk_wait_event(__sk, __timeo, __condition)			\
 881	({	int __rc;						\
 882		release_sock(__sk);					\
 883		__rc = __condition;					\
 884		if (!__rc) {						\
 885			*(__timeo) = schedule_timeout(*(__timeo));	\
 
 
 886		}							\
 
 887		lock_sock(__sk);					\
 888		__rc = __condition;					\
 889		__rc;							\
 890	})
 891
 892int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
 893int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
 894void sk_stream_wait_close(struct sock *sk, long timeo_p);
 895int sk_stream_error(struct sock *sk, int flags, int err);
 896void sk_stream_kill_queues(struct sock *sk);
 897void sk_set_memalloc(struct sock *sk);
 898void sk_clear_memalloc(struct sock *sk);
 899
 900int sk_wait_data(struct sock *sk, long *timeo);
 
 
 
 
 
 
 
 
 
 
 
 901
 902struct request_sock_ops;
 903struct timewait_sock_ops;
 904struct inet_hashinfo;
 905struct raw_hashinfo;
 
 906struct module;
 
 907
 908/*
 909 * caches using SLAB_DESTROY_BY_RCU should let .next pointer from nulls nodes
 910 * un-modified. Special care is taken when initializing object to zero.
 911 */
 912static inline void sk_prot_clear_nulls(struct sock *sk, int size)
 913{
 914	if (offsetof(struct sock, sk_node.next) != 0)
 915		memset(sk, 0, offsetof(struct sock, sk_node.next));
 916	memset(&sk->sk_node.pprev, 0,
 917	       size - offsetof(struct sock, sk_node.pprev));
 918}
 919
 
 
 
 
 
 
 
 920/* Networking protocol blocks we attach to sockets.
 921 * socket layer -> transport layer interface
 922 * transport -> network interface is defined by struct inet_proto
 923 */
 924struct proto {
 925	void			(*close)(struct sock *sk,
 926					long timeout);
 
 
 
 927	int			(*connect)(struct sock *sk,
 928					struct sockaddr *uaddr,
 929					int addr_len);
 930	int			(*disconnect)(struct sock *sk, int flags);
 931
 932	struct sock *		(*accept)(struct sock *sk, int flags, int *err);
 
 933
 934	int			(*ioctl)(struct sock *sk, int cmd,
 935					 unsigned long arg);
 936	int			(*init)(struct sock *sk);
 937	void			(*destroy)(struct sock *sk);
 938	void			(*shutdown)(struct sock *sk, int how);
 939	int			(*setsockopt)(struct sock *sk, int level,
 940					int optname, char __user *optval,
 941					unsigned int optlen);
 942	int			(*getsockopt)(struct sock *sk, int level,
 943					int optname, char __user *optval,
 944					int __user *option);
 
 945#ifdef CONFIG_COMPAT
 946	int			(*compat_setsockopt)(struct sock *sk,
 947					int level,
 948					int optname, char __user *optval,
 949					unsigned int optlen);
 950	int			(*compat_getsockopt)(struct sock *sk,
 951					int level,
 952					int optname, char __user *optval,
 953					int __user *option);
 954	int			(*compat_ioctl)(struct sock *sk,
 955					unsigned int cmd, unsigned long arg);
 956#endif
 957	int			(*sendmsg)(struct kiocb *iocb, struct sock *sk,
 958					   struct msghdr *msg, size_t len);
 959	int			(*recvmsg)(struct kiocb *iocb, struct sock *sk,
 960					   struct msghdr *msg,
 961					   size_t len, int noblock, int flags,
 962					   int *addr_len);
 963	int			(*sendpage)(struct sock *sk, struct page *page,
 964					int offset, size_t size, int flags);
 965	int			(*bind)(struct sock *sk,
 966					struct sockaddr *uaddr, int addr_len);
 
 
 967
 968	int			(*backlog_rcv) (struct sock *sk,
 969						struct sk_buff *skb);
 
 
 970
 971	void		(*release_cb)(struct sock *sk);
 972	void		(*mtu_reduced)(struct sock *sk);
 973
 974	/* Keeping track of sk's, looking them up, and port selection methods. */
 975	void			(*hash)(struct sock *sk);
 976	void			(*unhash)(struct sock *sk);
 977	void			(*rehash)(struct sock *sk);
 978	int			(*get_port)(struct sock *sk, unsigned short snum);
 979	void			(*clear_sk)(struct sock *sk, int size);
 
 
 
 
 
 980
 981	/* Keeping track of sockets in use */
 982#ifdef CONFIG_PROC_FS
 983	unsigned int		inuse_idx;
 984#endif
 985
 986	bool			(*stream_memory_free)(const struct sock *sk);
 
 
 
 
 
 987	/* Memory pressure */
 988	void			(*enter_memory_pressure)(struct sock *sk);
 
 989	atomic_long_t		*memory_allocated;	/* Current allocated memory. */
 
 990	struct percpu_counter	*sockets_allocated;	/* Current number of sockets. */
 
 991	/*
 992	 * Pressure flag: try to collapse.
 993	 * Technical note: it is used by multiple contexts non atomically.
 
 994	 * All the __sk_mem_schedule() is of this nature: accounting
 995	 * is strict, actions are advisory and have some latency.
 996	 */
 997	int			*memory_pressure;
 998	long			*sysctl_mem;
 
 999	int			*sysctl_wmem;
1000	int			*sysctl_rmem;
 
 
 
1001	int			max_header;
1002	bool			no_autobind;
1003
1004	struct kmem_cache	*slab;
1005	unsigned int		obj_size;
1006	int			slab_flags;
 
 
 
1007
1008	struct percpu_counter	*orphan_count;
1009
1010	struct request_sock_ops	*rsk_prot;
1011	struct timewait_sock_ops *twsk_prot;
1012
1013	union {
1014		struct inet_hashinfo	*hashinfo;
1015		struct udp_table	*udp_table;
1016		struct raw_hashinfo	*raw_hash;
 
1017	} h;
1018
1019	struct module		*owner;
1020
1021	char			name[32];
1022
1023	struct list_head	node;
1024#ifdef SOCK_REFCNT_DEBUG
1025	atomic_t		socks;
1026#endif
1027#ifdef CONFIG_MEMCG_KMEM
1028	/*
1029	 * cgroup specific init/deinit functions. Called once for all
1030	 * protocols that implement it, from cgroups populate function.
1031	 * This function has to setup any files the protocol want to
1032	 * appear in the kmem cgroup filesystem.
1033	 */
1034	int			(*init_cgroup)(struct mem_cgroup *memcg,
1035					       struct cgroup_subsys *ss);
1036	void			(*destroy_cgroup)(struct mem_cgroup *memcg);
1037	struct cg_proto		*(*proto_cgroup)(struct mem_cgroup *memcg);
1038#endif
1039};
1040
1041/*
1042 * Bits in struct cg_proto.flags
1043 */
1044enum cg_proto_flags {
1045	/* Currently active and new sockets should be assigned to cgroups */
1046	MEMCG_SOCK_ACTIVE,
1047	/* It was ever activated; we must disarm static keys on destruction */
1048	MEMCG_SOCK_ACTIVATED,
1049};
1050
1051struct cg_proto {
1052	struct res_counter	memory_allocated;	/* Current allocated memory. */
1053	struct percpu_counter	sockets_allocated;	/* Current number of sockets. */
1054	int			memory_pressure;
1055	long			sysctl_mem[3];
1056	unsigned long		flags;
1057	/*
1058	 * memcg field is used to find which memcg we belong directly
1059	 * Each memcg struct can hold more than one cg_proto, so container_of
1060	 * won't really cut.
1061	 *
1062	 * The elegant solution would be having an inverse function to
1063	 * proto_cgroup in struct proto, but that means polluting the structure
1064	 * for everybody, instead of just for memcg users.
1065	 */
1066	struct mem_cgroup	*memcg;
1067};
1068
1069int proto_register(struct proto *prot, int alloc_slab);
1070void proto_unregister(struct proto *prot);
 
1071
1072static inline bool memcg_proto_active(struct cg_proto *cg_proto)
1073{
1074	return test_bit(MEMCG_SOCK_ACTIVE, &cg_proto->flags);
1075}
1076
1077static inline bool memcg_proto_activated(struct cg_proto *cg_proto)
1078{
1079	return test_bit(MEMCG_SOCK_ACTIVATED, &cg_proto->flags);
 
 
 
 
1080}
1081
1082#ifdef SOCK_REFCNT_DEBUG
1083static inline void sk_refcnt_debug_inc(struct sock *sk)
1084{
1085	atomic_inc(&sk->sk_prot->socks);
1086}
1087
1088static inline void sk_refcnt_debug_dec(struct sock *sk)
1089{
1090	atomic_dec(&sk->sk_prot->socks);
1091	printk(KERN_DEBUG "%s socket %p released, %d are still alive\n",
1092	       sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks));
1093}
1094
1095static inline void sk_refcnt_debug_release(const struct sock *sk)
1096{
1097	if (atomic_read(&sk->sk_refcnt) != 1)
1098		printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n",
1099		       sk->sk_prot->name, sk, atomic_read(&sk->sk_refcnt));
1100}
1101#else /* SOCK_REFCNT_DEBUG */
1102#define sk_refcnt_debug_inc(sk) do { } while (0)
1103#define sk_refcnt_debug_dec(sk) do { } while (0)
1104#define sk_refcnt_debug_release(sk) do { } while (0)
1105#endif /* SOCK_REFCNT_DEBUG */
1106
1107#if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_NET)
1108extern struct static_key memcg_socket_limit_enabled;
1109static inline struct cg_proto *parent_cg_proto(struct proto *proto,
1110					       struct cg_proto *cg_proto)
1111{
1112	return proto->proto_cgroup(parent_mem_cgroup(cg_proto->memcg));
1113}
1114#define mem_cgroup_sockets_enabled static_key_false(&memcg_socket_limit_enabled)
1115#else
1116#define mem_cgroup_sockets_enabled 0
1117static inline struct cg_proto *parent_cg_proto(struct proto *proto,
1118					       struct cg_proto *cg_proto)
1119{
1120	return NULL;
1121}
1122#endif
1123
1124static inline bool sk_stream_memory_free(const struct sock *sk)
1125{
1126	if (sk->sk_wmem_queued >= sk->sk_sndbuf)
1127		return false;
1128
1129	return sk->sk_prot->stream_memory_free ?
1130		sk->sk_prot->stream_memory_free(sk) : true;
1131}
1132
1133static inline bool sk_stream_is_writeable(const struct sock *sk)
1134{
1135	return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) &&
1136	       sk_stream_memory_free(sk);
1137}
1138
1139
1140static inline bool sk_has_memory_pressure(const struct sock *sk)
1141{
1142	return sk->sk_prot->memory_pressure != NULL;
1143}
1144
1145static inline bool sk_under_memory_pressure(const struct sock *sk)
 
1146{
1147	if (!sk->sk_prot->memory_pressure)
1148		return false;
1149
1150	if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1151		return !!sk->sk_cgrp->memory_pressure;
1152
1153	return !!*sk->sk_prot->memory_pressure;
1154}
1155
1156static inline void sk_leave_memory_pressure(struct sock *sk)
1157{
1158	int *memory_pressure = sk->sk_prot->memory_pressure;
1159
1160	if (!memory_pressure)
1161		return;
1162
1163	if (*memory_pressure)
1164		*memory_pressure = 0;
1165
1166	if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1167		struct cg_proto *cg_proto = sk->sk_cgrp;
1168		struct proto *prot = sk->sk_prot;
1169
1170		for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto))
1171			cg_proto->memory_pressure = 0;
1172	}
1173
1174}
1175
1176static inline void sk_enter_memory_pressure(struct sock *sk)
1177{
1178	if (!sk->sk_prot->enter_memory_pressure)
1179		return;
1180
1181	if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1182		struct cg_proto *cg_proto = sk->sk_cgrp;
1183		struct proto *prot = sk->sk_prot;
1184
1185		for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto))
1186			cg_proto->memory_pressure = 1;
1187	}
1188
1189	sk->sk_prot->enter_memory_pressure(sk);
1190}
1191
1192static inline long sk_prot_mem_limits(const struct sock *sk, int index)
1193{
1194	long *prot = sk->sk_prot->sysctl_mem;
1195	if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1196		prot = sk->sk_cgrp->sysctl_mem;
1197	return prot[index];
1198}
1199
1200static inline void memcg_memory_allocated_add(struct cg_proto *prot,
1201					      unsigned long amt,
1202					      int *parent_status)
1203{
1204	struct res_counter *fail;
1205	int ret;
1206
1207	ret = res_counter_charge_nofail(&prot->memory_allocated,
1208					amt << PAGE_SHIFT, &fail);
1209	if (ret < 0)
1210		*parent_status = OVER_LIMIT;
1211}
1212
1213static inline void memcg_memory_allocated_sub(struct cg_proto *prot,
1214					      unsigned long amt)
1215{
1216	res_counter_uncharge(&prot->memory_allocated, amt << PAGE_SHIFT);
1217}
1218
1219static inline u64 memcg_memory_allocated_read(struct cg_proto *prot)
1220{
1221	u64 ret;
1222	ret = res_counter_read_u64(&prot->memory_allocated, RES_USAGE);
1223	return ret >> PAGE_SHIFT;
1224}
1225
1226static inline long
1227sk_memory_allocated(const struct sock *sk)
1228{
1229	struct proto *prot = sk->sk_prot;
1230	if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1231		return memcg_memory_allocated_read(sk->sk_cgrp);
1232
1233	return atomic_long_read(prot->memory_allocated);
1234}
1235
1236static inline long
1237sk_memory_allocated_add(struct sock *sk, int amt, int *parent_status)
1238{
1239	struct proto *prot = sk->sk_prot;
1240
1241	if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1242		memcg_memory_allocated_add(sk->sk_cgrp, amt, parent_status);
1243		/* update the root cgroup regardless */
1244		atomic_long_add_return(amt, prot->memory_allocated);
1245		return memcg_memory_allocated_read(sk->sk_cgrp);
1246	}
1247
1248	return atomic_long_add_return(amt, prot->memory_allocated);
1249}
1250
1251static inline void
1252sk_memory_allocated_sub(struct sock *sk, int amt)
1253{
1254	struct proto *prot = sk->sk_prot;
1255
1256	if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1257		memcg_memory_allocated_sub(sk->sk_cgrp, amt);
1258
1259	atomic_long_sub(amt, prot->memory_allocated);
1260}
1261
1262static inline void sk_sockets_allocated_dec(struct sock *sk)
1263{
1264	struct proto *prot = sk->sk_prot;
1265
1266	if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1267		struct cg_proto *cg_proto = sk->sk_cgrp;
1268
1269		for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto))
1270			percpu_counter_dec(&cg_proto->sockets_allocated);
1271	}
1272
1273	percpu_counter_dec(prot->sockets_allocated);
1274}
1275
1276static inline void sk_sockets_allocated_inc(struct sock *sk)
1277{
1278	struct proto *prot = sk->sk_prot;
1279
1280	if (mem_cgroup_sockets_enabled && sk->sk_cgrp) {
1281		struct cg_proto *cg_proto = sk->sk_cgrp;
1282
1283		for (; cg_proto; cg_proto = parent_cg_proto(prot, cg_proto))
1284			percpu_counter_inc(&cg_proto->sockets_allocated);
1285	}
1286
1287	percpu_counter_inc(prot->sockets_allocated);
1288}
1289
1290static inline int
1291sk_sockets_allocated_read_positive(struct sock *sk)
1292{
1293	struct proto *prot = sk->sk_prot;
1294
1295	if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1296		return percpu_counter_read_positive(&sk->sk_cgrp->sockets_allocated);
1297
1298	return percpu_counter_read_positive(prot->sockets_allocated);
1299}
1300
1301static inline int
1302proto_sockets_allocated_sum_positive(struct proto *prot)
1303{
1304	return percpu_counter_sum_positive(prot->sockets_allocated);
1305}
1306
1307static inline long
1308proto_memory_allocated(struct proto *prot)
 
 
 
 
 
 
 
1309{
1310	return atomic_long_read(prot->memory_allocated);
1311}
1312
1313static inline bool
1314proto_memory_pressure(struct proto *prot)
1315{
1316	if (!prot->memory_pressure)
1317		return false;
1318	return !!*prot->memory_pressure;
1319}
1320
1321
1322#ifdef CONFIG_PROC_FS
1323/* Called with local bh disabled */
1324void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc);
1325int sock_prot_inuse_get(struct net *net, struct proto *proto);
 
1326#else
1327static inline void sock_prot_inuse_add(struct net *net, struct proto *prot,
1328		int inc)
 
 
 
 
1329{
1330}
1331#endif
1332
1333
1334/* With per-bucket locks this operation is not-atomic, so that
1335 * this version is not worse.
1336 */
1337static inline void __sk_prot_rehash(struct sock *sk)
1338{
1339	sk->sk_prot->unhash(sk);
1340	sk->sk_prot->hash(sk);
1341}
1342
1343void sk_prot_clear_portaddr_nulls(struct sock *sk, int size);
1344
1345/* About 10 seconds */
1346#define SOCK_DESTROY_TIME (10*HZ)
1347
1348/* Sockets 0-1023 can't be bound to unless you are superuser */
1349#define PROT_SOCK	1024
1350
1351#define SHUTDOWN_MASK	3
1352#define RCV_SHUTDOWN	1
1353#define SEND_SHUTDOWN	2
1354
1355#define SOCK_SNDBUF_LOCK	1
1356#define SOCK_RCVBUF_LOCK	2
1357#define SOCK_BINDADDR_LOCK	4
1358#define SOCK_BINDPORT_LOCK	8
1359
1360/* sock_iocb: used to kick off async processing of socket ios */
1361struct sock_iocb {
1362	struct list_head	list;
1363
1364	int			flags;
1365	int			size;
1366	struct socket		*sock;
1367	struct sock		*sk;
1368	struct scm_cookie	*scm;
1369	struct msghdr		*msg, async_msg;
1370	struct kiocb		*kiocb;
1371};
1372
1373static inline struct sock_iocb *kiocb_to_siocb(struct kiocb *iocb)
1374{
1375	return (struct sock_iocb *)iocb->private;
1376}
1377
1378static inline struct kiocb *siocb_to_kiocb(struct sock_iocb *si)
1379{
1380	return si->kiocb;
1381}
1382
1383struct socket_alloc {
1384	struct socket socket;
1385	struct inode vfs_inode;
1386};
1387
1388static inline struct socket *SOCKET_I(struct inode *inode)
1389{
1390	return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
1391}
1392
1393static inline struct inode *SOCK_INODE(struct socket *socket)
1394{
1395	return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
1396}
1397
1398/*
1399 * Functions for memory accounting
1400 */
 
1401int __sk_mem_schedule(struct sock *sk, int size, int kind);
1402void __sk_mem_reclaim(struct sock *sk);
 
1403
1404#define SK_MEM_QUANTUM ((int)PAGE_SIZE)
1405#define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM)
1406#define SK_MEM_SEND	0
1407#define SK_MEM_RECV	1
1408
 
 
 
 
 
 
1409static inline int sk_mem_pages(int amt)
1410{
1411	return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT;
1412}
1413
1414static inline bool sk_has_account(struct sock *sk)
1415{
1416	/* return true if protocol supports memory accounting */
1417	return !!sk->sk_prot->memory_allocated;
1418}
1419
1420static inline bool sk_wmem_schedule(struct sock *sk, int size)
1421{
 
 
1422	if (!sk_has_account(sk))
1423		return true;
1424	return size <= sk->sk_forward_alloc ||
1425		__sk_mem_schedule(sk, size, SK_MEM_SEND);
1426}
1427
1428static inline bool
1429sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size)
1430{
 
 
1431	if (!sk_has_account(sk))
1432		return true;
1433	return size<= sk->sk_forward_alloc ||
1434		__sk_mem_schedule(sk, size, SK_MEM_RECV) ||
1435		skb_pfmemalloc(skb);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1436}
1437
1438static inline void sk_mem_reclaim(struct sock *sk)
1439{
 
 
1440	if (!sk_has_account(sk))
1441		return;
1442	if (sk->sk_forward_alloc >= SK_MEM_QUANTUM)
1443		__sk_mem_reclaim(sk);
 
 
 
1444}
1445
1446static inline void sk_mem_reclaim_partial(struct sock *sk)
1447{
1448	if (!sk_has_account(sk))
1449		return;
1450	if (sk->sk_forward_alloc > SK_MEM_QUANTUM)
1451		__sk_mem_reclaim(sk);
1452}
1453
1454static inline void sk_mem_charge(struct sock *sk, int size)
1455{
1456	if (!sk_has_account(sk))
1457		return;
1458	sk->sk_forward_alloc -= size;
1459}
1460
1461static inline void sk_mem_uncharge(struct sock *sk, int size)
1462{
1463	if (!sk_has_account(sk))
1464		return;
1465	sk->sk_forward_alloc += size;
1466}
1467
1468static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb)
1469{
1470	sock_set_flag(sk, SOCK_QUEUE_SHRUNK);
1471	sk->sk_wmem_queued -= skb->truesize;
1472	sk_mem_uncharge(sk, skb->truesize);
1473	__kfree_skb(skb);
1474}
1475
1476/* Used by processes to "lock" a socket state, so that
1477 * interrupts and bottom half handlers won't change it
1478 * from under us. It essentially blocks any incoming
1479 * packets, so that we won't get any new data or any
1480 * packets that change the state of the socket.
1481 *
1482 * While locked, BH processing will add new packets to
1483 * the backlog queue.  This queue is processed by the
1484 * owner of the socket lock right before it is released.
1485 *
1486 * Since ~2.3.5 it is also exclusive sleep lock serializing
1487 * accesses from user process context.
1488 */
1489#define sock_owned_by_user(sk)	((sk)->sk_lock.owned)
1490
1491static inline void sock_release_ownership(struct sock *sk)
1492{
1493	sk->sk_lock.owned = 0;
1494}
1495
1496/*
1497 * Macro so as to not evaluate some arguments when
1498 * lockdep is not enabled.
1499 *
1500 * Mark both the sk_lock and the sk_lock.slock as a
1501 * per-address-family lock class.
1502 */
1503#define sock_lock_init_class_and_name(sk, sname, skey, name, key)	\
1504do {									\
1505	sk->sk_lock.owned = 0;						\
1506	init_waitqueue_head(&sk->sk_lock.wq);				\
1507	spin_lock_init(&(sk)->sk_lock.slock);				\
1508	debug_check_no_locks_freed((void *)&(sk)->sk_lock,		\
1509			sizeof((sk)->sk_lock));				\
1510	lockdep_set_class_and_name(&(sk)->sk_lock.slock,		\
1511				(skey), (sname));				\
1512	lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0);	\
1513} while (0)
1514
 
 
 
 
 
 
1515void lock_sock_nested(struct sock *sk, int subclass);
1516
1517static inline void lock_sock(struct sock *sk)
1518{
1519	lock_sock_nested(sk, 0);
1520}
1521
 
 
1522void release_sock(struct sock *sk);
1523
1524/* BH context may only use the following locking interface. */
1525#define bh_lock_sock(__sk)	spin_lock(&((__sk)->sk_lock.slock))
1526#define bh_lock_sock_nested(__sk) \
1527				spin_lock_nested(&((__sk)->sk_lock.slock), \
1528				SINGLE_DEPTH_NESTING)
1529#define bh_unlock_sock(__sk)	spin_unlock(&((__sk)->sk_lock.slock))
1530
1531bool lock_sock_fast(struct sock *sk);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1532/**
1533 * unlock_sock_fast - complement of lock_sock_fast
1534 * @sk: socket
1535 * @slow: slow mode
1536 *
1537 * fast unlock socket for user context.
1538 * If slow mode is on, we call regular release_sock()
1539 */
1540static inline void unlock_sock_fast(struct sock *sk, bool slow)
 
1541{
1542	if (slow)
1543		release_sock(sk);
1544	else
 
 
1545		spin_unlock_bh(&sk->sk_lock.slock);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1546}
1547
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1548
1549struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1550		      struct proto *prot);
1551void sk_free(struct sock *sk);
1552void sk_release_kernel(struct sock *sk);
 
1553struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority);
 
1554
1555struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1556			     gfp_t priority);
 
1557void sock_wfree(struct sk_buff *skb);
 
 
1558void skb_orphan_partial(struct sk_buff *skb);
1559void sock_rfree(struct sk_buff *skb);
 
 
1560void sock_edemux(struct sk_buff *skb);
 
1561
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1562int sock_setsockopt(struct socket *sock, int level, int op,
1563		    char __user *optval, unsigned int optlen);
1564
1565int sock_getsockopt(struct socket *sock, int level, int op,
1566		    char __user *optval, int __user *optlen);
1567struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1568				    int noblock, int *errcode);
 
 
 
 
1569struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1570				     unsigned long data_len, int noblock,
1571				     int *errcode, int max_page_order);
 
 
 
 
 
 
 
 
1572void *sock_kmalloc(struct sock *sk, int size, gfp_t priority);
1573void sock_kfree_s(struct sock *sk, void *mem, int size);
 
1574void sk_send_sigurg(struct sock *sk);
1575
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1576/*
1577 * Functions to fill in entries in struct proto_ops when a protocol
1578 * does not implement a particular function.
1579 */
1580int sock_no_bind(struct socket *, struct sockaddr *, int);
1581int sock_no_connect(struct socket *, struct sockaddr *, int, int);
1582int sock_no_socketpair(struct socket *, struct socket *);
1583int sock_no_accept(struct socket *, struct socket *, int);
1584int sock_no_getname(struct socket *, struct sockaddr *, int *, int);
1585unsigned int sock_no_poll(struct file *, struct socket *,
1586			  struct poll_table_struct *);
1587int sock_no_ioctl(struct socket *, unsigned int, unsigned long);
1588int sock_no_listen(struct socket *, int);
1589int sock_no_shutdown(struct socket *, int);
1590int sock_no_getsockopt(struct socket *, int , int, char __user *, int __user *);
1591int sock_no_setsockopt(struct socket *, int, int, char __user *, unsigned int);
1592int sock_no_sendmsg(struct kiocb *, struct socket *, struct msghdr *, size_t);
1593int sock_no_recvmsg(struct kiocb *, struct socket *, struct msghdr *, size_t,
1594		    int);
1595int sock_no_mmap(struct file *file, struct socket *sock,
1596		 struct vm_area_struct *vma);
1597ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset,
1598			 size_t size, int flags);
1599
1600/*
1601 * Functions to fill in entries in struct proto_ops when a protocol
1602 * uses the inet style.
1603 */
1604int sock_common_getsockopt(struct socket *sock, int level, int optname,
1605				  char __user *optval, int __user *optlen);
1606int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock,
1607			       struct msghdr *msg, size_t size, int flags);
1608int sock_common_setsockopt(struct socket *sock, int level, int optname,
1609				  char __user *optval, unsigned int optlen);
1610int compat_sock_common_getsockopt(struct socket *sock, int level,
1611		int optname, char __user *optval, int __user *optlen);
1612int compat_sock_common_setsockopt(struct socket *sock, int level,
1613		int optname, char __user *optval, unsigned int optlen);
1614
1615void sk_common_release(struct sock *sk);
1616
1617/*
1618 *	Default socket callbacks and setup code
1619 */
1620
1621/* Initialise core socket variables */
 
 
 
 
 
1622void sock_init_data(struct socket *sock, struct sock *sk);
1623
1624/*
1625 * Socket reference counting postulates.
1626 *
1627 * * Each user of socket SHOULD hold a reference count.
1628 * * Each access point to socket (an hash table bucket, reference from a list,
1629 *   running timer, skb in flight MUST hold a reference count.
1630 * * When reference count hits 0, it means it will never increase back.
1631 * * When reference count hits 0, it means that no references from
1632 *   outside exist to this socket and current process on current CPU
1633 *   is last user and may/should destroy this socket.
1634 * * sk_free is called from any context: process, BH, IRQ. When
1635 *   it is called, socket has no references from outside -> sk_free
1636 *   may release descendant resources allocated by the socket, but
1637 *   to the time when it is called, socket is NOT referenced by any
1638 *   hash tables, lists etc.
1639 * * Packets, delivered from outside (from network or from another process)
1640 *   and enqueued on receive/error queues SHOULD NOT grab reference count,
1641 *   when they sit in queue. Otherwise, packets will leak to hole, when
1642 *   socket is looked up by one cpu and unhasing is made by another CPU.
1643 *   It is true for udp/raw, netlink (leak to receive and error queues), tcp
1644 *   (leak to backlog). Packet socket does all the processing inside
1645 *   BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
1646 *   use separate SMP lock, so that they are prone too.
1647 */
1648
1649/* Ungrab socket and destroy it, if it was the last reference. */
1650static inline void sock_put(struct sock *sk)
1651{
1652	if (atomic_dec_and_test(&sk->sk_refcnt))
1653		sk_free(sk);
1654}
1655/* Generic version of sock_put(), dealing with all sockets
1656 * (TCP_TIMEWAIT, ESTABLISHED...)
1657 */
1658void sock_gen_put(struct sock *sk);
1659
1660int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested);
 
 
 
 
 
 
1661
1662static inline void sk_tx_queue_set(struct sock *sk, int tx_queue)
1663{
1664	sk->sk_tx_queue_mapping = tx_queue;
 
 
 
 
 
 
1665}
1666
 
 
1667static inline void sk_tx_queue_clear(struct sock *sk)
1668{
1669	sk->sk_tx_queue_mapping = -1;
 
 
 
1670}
1671
1672static inline int sk_tx_queue_get(const struct sock *sk)
1673{
1674	return sk ? sk->sk_tx_queue_mapping : -1;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1675}
1676
1677static inline void sk_set_socket(struct sock *sk, struct socket *sock)
1678{
1679	sk_tx_queue_clear(sk);
1680	sk->sk_socket = sock;
1681}
1682
1683static inline wait_queue_head_t *sk_sleep(struct sock *sk)
1684{
1685	BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0);
1686	return &rcu_dereference_raw(sk->sk_wq)->wait;
1687}
1688/* Detach socket from process context.
1689 * Announce socket dead, detach it from wait queue and inode.
1690 * Note that parent inode held reference count on this struct sock,
1691 * we do not release it in this function, because protocol
1692 * probably wants some additional cleanups or even continuing
1693 * to work with this socket (TCP).
1694 */
1695static inline void sock_orphan(struct sock *sk)
1696{
1697	write_lock_bh(&sk->sk_callback_lock);
1698	sock_set_flag(sk, SOCK_DEAD);
1699	sk_set_socket(sk, NULL);
1700	sk->sk_wq  = NULL;
1701	write_unlock_bh(&sk->sk_callback_lock);
1702}
1703
1704static inline void sock_graft(struct sock *sk, struct socket *parent)
1705{
 
1706	write_lock_bh(&sk->sk_callback_lock);
1707	sk->sk_wq = parent->wq;
1708	parent->sk = sk;
1709	sk_set_socket(sk, parent);
 
1710	security_sock_graft(sk, parent);
1711	write_unlock_bh(&sk->sk_callback_lock);
1712}
1713
1714kuid_t sock_i_uid(struct sock *sk);
 
1715unsigned long sock_i_ino(struct sock *sk);
1716
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1717static inline struct dst_entry *
1718__sk_dst_get(struct sock *sk)
1719{
1720	return rcu_dereference_check(sk->sk_dst_cache, sock_owned_by_user(sk) ||
1721						       lockdep_is_held(&sk->sk_lock.slock));
1722}
1723
1724static inline struct dst_entry *
1725sk_dst_get(struct sock *sk)
1726{
1727	struct dst_entry *dst;
1728
1729	rcu_read_lock();
1730	dst = rcu_dereference(sk->sk_dst_cache);
1731	if (dst)
1732		dst_hold(dst);
1733	rcu_read_unlock();
1734	return dst;
1735}
1736
1737static inline void dst_negative_advice(struct sock *sk)
1738{
1739	struct dst_entry *ndst, *dst = __sk_dst_get(sk);
1740
1741	if (dst && dst->ops->negative_advice) {
1742		ndst = dst->ops->negative_advice(dst);
 
1743
1744		if (ndst != dst) {
1745			rcu_assign_pointer(sk->sk_dst_cache, ndst);
1746			sk_tx_queue_clear(sk);
1747		}
1748	}
1749}
1750
1751static inline void
1752__sk_dst_set(struct sock *sk, struct dst_entry *dst)
1753{
1754	struct dst_entry *old_dst;
1755
1756	sk_tx_queue_clear(sk);
1757	/*
1758	 * This can be called while sk is owned by the caller only,
1759	 * with no state that can be checked in a rcu_dereference_check() cond
1760	 */
1761	old_dst = rcu_dereference_raw(sk->sk_dst_cache);
1762	rcu_assign_pointer(sk->sk_dst_cache, dst);
1763	dst_release(old_dst);
1764}
1765
1766static inline void
1767sk_dst_set(struct sock *sk, struct dst_entry *dst)
1768{
1769	spin_lock(&sk->sk_dst_lock);
1770	__sk_dst_set(sk, dst);
1771	spin_unlock(&sk->sk_dst_lock);
 
 
 
1772}
1773
1774static inline void
1775__sk_dst_reset(struct sock *sk)
1776{
1777	__sk_dst_set(sk, NULL);
1778}
1779
1780static inline void
1781sk_dst_reset(struct sock *sk)
1782{
1783	spin_lock(&sk->sk_dst_lock);
1784	__sk_dst_reset(sk);
1785	spin_unlock(&sk->sk_dst_lock);
1786}
1787
1788struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
1789
1790struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
1791
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1792static inline bool sk_can_gso(const struct sock *sk)
1793{
1794	return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type);
1795}
1796
1797void sk_setup_caps(struct sock *sk, struct dst_entry *dst);
1798
1799static inline void sk_nocaps_add(struct sock *sk, netdev_features_t flags)
1800{
1801	sk->sk_route_nocaps |= flags;
1802	sk->sk_route_caps &= ~flags;
1803}
1804
1805static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
1806					   char __user *from, char *to,
1807					   int copy, int offset)
1808{
1809	if (skb->ip_summed == CHECKSUM_NONE) {
1810		int err = 0;
1811		__wsum csum = csum_and_copy_from_user(from, to, copy, 0, &err);
1812		if (err)
1813			return err;
1814		skb->csum = csum_block_add(skb->csum, csum, offset);
1815	} else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
1816		if (!access_ok(VERIFY_READ, from, copy) ||
1817		    __copy_from_user_nocache(to, from, copy))
1818			return -EFAULT;
1819	} else if (copy_from_user(to, from, copy))
1820		return -EFAULT;
1821
1822	return 0;
1823}
1824
1825static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
1826				       char __user *from, int copy)
1827{
1828	int err, offset = skb->len;
1829
1830	err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy),
1831				       copy, offset);
1832	if (err)
1833		__skb_trim(skb, offset);
1834
1835	return err;
1836}
1837
1838static inline int skb_copy_to_page_nocache(struct sock *sk, char __user *from,
1839					   struct sk_buff *skb,
1840					   struct page *page,
1841					   int off, int copy)
1842{
1843	int err;
1844
1845	err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off,
1846				       copy, skb->len);
1847	if (err)
1848		return err;
1849
1850	skb->len	     += copy;
1851	skb->data_len	     += copy;
1852	skb->truesize	     += copy;
1853	sk->sk_wmem_queued   += copy;
1854	sk_mem_charge(sk, copy);
1855	return 0;
1856}
1857
1858static inline int skb_copy_to_page(struct sock *sk, char __user *from,
1859				   struct sk_buff *skb, struct page *page,
1860				   int off, int copy)
1861{
1862	if (skb->ip_summed == CHECKSUM_NONE) {
1863		int err = 0;
1864		__wsum csum = csum_and_copy_from_user(from,
1865						     page_address(page) + off,
1866							    copy, 0, &err);
1867		if (err)
1868			return err;
1869		skb->csum = csum_block_add(skb->csum, csum, skb->len);
1870	} else if (copy_from_user(page_address(page) + off, from, copy))
1871		return -EFAULT;
1872
1873	skb->len	     += copy;
1874	skb->data_len	     += copy;
1875	skb->truesize	     += copy;
1876	sk->sk_wmem_queued   += copy;
1877	sk_mem_charge(sk, copy);
1878	return 0;
1879}
1880
1881/**
1882 * sk_wmem_alloc_get - returns write allocations
1883 * @sk: socket
1884 *
1885 * Returns sk_wmem_alloc minus initial offset of one
1886 */
1887static inline int sk_wmem_alloc_get(const struct sock *sk)
1888{
1889	return atomic_read(&sk->sk_wmem_alloc) - 1;
1890}
1891
1892/**
1893 * sk_rmem_alloc_get - returns read allocations
1894 * @sk: socket
1895 *
1896 * Returns sk_rmem_alloc
1897 */
1898static inline int sk_rmem_alloc_get(const struct sock *sk)
1899{
1900	return atomic_read(&sk->sk_rmem_alloc);
1901}
1902
1903/**
1904 * sk_has_allocations - check if allocations are outstanding
1905 * @sk: socket
1906 *
1907 * Returns true if socket has write or read allocations
1908 */
1909static inline bool sk_has_allocations(const struct sock *sk)
1910{
1911	return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk);
1912}
1913
1914/**
1915 * wq_has_sleeper - check if there are any waiting processes
1916 * @wq: struct socket_wq
1917 *
1918 * Returns true if socket_wq has waiting processes
1919 *
1920 * The purpose of the wq_has_sleeper and sock_poll_wait is to wrap the memory
1921 * barrier call. They were added due to the race found within the tcp code.
1922 *
1923 * Consider following tcp code paths:
1924 *
1925 * CPU1                  CPU2
1926 *
1927 * sys_select            receive packet
 
1928 *   ...                 ...
1929 *   __add_wait_queue    update tp->rcv_nxt
1930 *   ...                 ...
1931 *   tp->rcv_nxt check   sock_def_readable
1932 *   ...                 {
1933 *   schedule               rcu_read_lock();
1934 *                          wq = rcu_dereference(sk->sk_wq);
1935 *                          if (wq && waitqueue_active(&wq->wait))
1936 *                              wake_up_interruptible(&wq->wait)
1937 *                          ...
1938 *                       }
1939 *
1940 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
1941 * in its cache, and so does the tp->rcv_nxt update on CPU2 side.  The CPU1
1942 * could then endup calling schedule and sleep forever if there are no more
1943 * data on the socket.
1944 *
1945 */
1946static inline bool wq_has_sleeper(struct socket_wq *wq)
1947{
1948	/* We need to be sure we are in sync with the
1949	 * add_wait_queue modifications to the wait queue.
1950	 *
1951	 * This memory barrier is paired in the sock_poll_wait.
1952	 */
1953	smp_mb();
1954	return wq && waitqueue_active(&wq->wait);
1955}
1956
1957/**
1958 * sock_poll_wait - place memory barrier behind the poll_wait call.
1959 * @filp:           file
1960 * @wait_address:   socket wait queue
1961 * @p:              poll_table
1962 *
1963 * See the comments in the wq_has_sleeper function.
1964 */
1965static inline void sock_poll_wait(struct file *filp,
1966		wait_queue_head_t *wait_address, poll_table *p)
 
 
 
 
 
 
 
 
 
 
1967{
1968	if (!poll_does_not_wait(p) && wait_address) {
1969		poll_wait(filp, wait_address, p);
1970		/* We need to be sure we are in sync with the
1971		 * socket flags modification.
1972		 *
1973		 * This memory barrier is paired in the wq_has_sleeper.
1974		 */
1975		smp_mb();
1976	}
1977}
1978
 
 
1979/*
1980 *	Queue a received datagram if it will fit. Stream and sequenced
1981 *	protocols can't normally use this as they need to fit buffers in
1982 *	and play with them.
1983 *
1984 *	Inlined as it's very short and called for pretty much every
1985 *	packet ever received.
1986 */
1987
1988static inline void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
1989{
1990	skb_orphan(skb);
1991	skb->sk = sk;
1992	skb->destructor = sock_wfree;
1993	/*
1994	 * We used to take a refcount on sk, but following operation
1995	 * is enough to guarantee sk_free() wont free this sock until
1996	 * all in-flight packets are completed
1997	 */
1998	atomic_add(skb->truesize, &sk->sk_wmem_alloc);
1999}
2000
2001static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
2002{
2003	skb_orphan(skb);
2004	skb->sk = sk;
2005	skb->destructor = sock_rfree;
2006	atomic_add(skb->truesize, &sk->sk_rmem_alloc);
2007	sk_mem_charge(sk, skb->truesize);
2008}
2009
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2010void sk_reset_timer(struct sock *sk, struct timer_list *timer,
2011		    unsigned long expires);
2012
2013void sk_stop_timer(struct sock *sk, struct timer_list *timer);
2014
2015int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2016
2017int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
 
2018
2019/*
2020 *	Recover an error report and clear atomically
2021 */
2022
2023static inline int sock_error(struct sock *sk)
2024{
2025	int err;
2026	if (likely(!sk->sk_err))
 
 
 
 
2027		return 0;
 
2028	err = xchg(&sk->sk_err, 0);
2029	return -err;
2030}
2031
 
 
2032static inline unsigned long sock_wspace(struct sock *sk)
2033{
2034	int amt = 0;
2035
2036	if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
2037		amt = sk->sk_sndbuf - atomic_read(&sk->sk_wmem_alloc);
2038		if (amt < 0)
2039			amt = 0;
2040	}
2041	return amt;
2042}
2043
2044static inline void sk_wake_async(struct sock *sk, int how, int band)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2045{
2046	if (sock_flag(sk, SOCK_FASYNC))
2047		sock_wake_async(sk->sk_socket, how, band);
 
 
 
 
 
 
 
 
 
2048}
2049
2050/* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might
2051 * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak.
2052 * Note: for send buffers, TCP works better if we can build two skbs at
2053 * minimum.
2054 */
2055#define TCP_SKB_MIN_TRUESIZE	(2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff)))
2056
2057#define SOCK_MIN_SNDBUF		(TCP_SKB_MIN_TRUESIZE * 2)
2058#define SOCK_MIN_RCVBUF		 TCP_SKB_MIN_TRUESIZE
2059
2060static inline void sk_stream_moderate_sndbuf(struct sock *sk)
2061{
2062	if (!(sk->sk_userlocks & SOCK_SNDBUF_LOCK)) {
2063		sk->sk_sndbuf = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
2064		sk->sk_sndbuf = max_t(u32, sk->sk_sndbuf, SOCK_MIN_SNDBUF);
2065	}
 
 
 
 
 
2066}
2067
2068struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp);
2069
2070/**
2071 * sk_page_frag - return an appropriate page_frag
2072 * @sk: socket
2073 *
2074 * If socket allocation mode allows current thread to sleep, it means its
2075 * safe to use the per task page_frag instead of the per socket one.
 
 
 
 
 
 
 
 
 
2076 */
2077static inline struct page_frag *sk_page_frag(struct sock *sk)
2078{
2079	if (sk->sk_allocation & __GFP_WAIT)
2080		return &current->task_frag;
2081
2082	return &sk->sk_frag;
2083}
2084
2085bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag);
2086
2087/*
2088 *	Default write policy as shown to user space via poll/select/SIGIO
2089 */
2090static inline bool sock_writeable(const struct sock *sk)
2091{
2092	return atomic_read(&sk->sk_wmem_alloc) < (sk->sk_sndbuf >> 1);
2093}
2094
2095static inline gfp_t gfp_any(void)
2096{
2097	return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2098}
2099
 
 
 
 
 
2100static inline long sock_rcvtimeo(const struct sock *sk, bool noblock)
2101{
2102	return noblock ? 0 : sk->sk_rcvtimeo;
2103}
2104
2105static inline long sock_sndtimeo(const struct sock *sk, bool noblock)
2106{
2107	return noblock ? 0 : sk->sk_sndtimeo;
2108}
2109
2110static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
2111{
2112	return (waitall ? len : min_t(int, sk->sk_rcvlowat, len)) ? : 1;
 
 
2113}
2114
2115/* Alas, with timeout socket operations are not restartable.
2116 * Compare this to poll().
2117 */
2118static inline int sock_intr_errno(long timeo)
2119{
2120	return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
2121}
2122
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2123void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
2124			   struct sk_buff *skb);
2125void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
2126			     struct sk_buff *skb);
2127
2128static inline void
2129sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
2130{
 
 
2131	ktime_t kt = skb->tstamp;
2132	struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
2133
2134	/*
2135	 * generate control messages if
2136	 * - receive time stamping in software requested (SOCK_RCVTSTAMP
2137	 *   or SOCK_TIMESTAMPING_RX_SOFTWARE)
2138	 * - software time stamp available and wanted
2139	 *   (SOCK_TIMESTAMPING_SOFTWARE)
2140	 * - hardware time stamps available and wanted
2141	 *   (SOCK_TIMESTAMPING_SYS_HARDWARE or
2142	 *   SOCK_TIMESTAMPING_RAW_HARDWARE)
2143	 */
2144	if (sock_flag(sk, SOCK_RCVTSTAMP) ||
2145	    sock_flag(sk, SOCK_TIMESTAMPING_RX_SOFTWARE) ||
2146	    (kt.tv64 && sock_flag(sk, SOCK_TIMESTAMPING_SOFTWARE)) ||
2147	    (hwtstamps->hwtstamp.tv64 &&
2148	     sock_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE)) ||
2149	    (hwtstamps->syststamp.tv64 &&
2150	     sock_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE)))
2151		__sock_recv_timestamp(msg, sk, skb);
2152	else
2153		sk->sk_stamp = kt;
2154
2155	if (sock_flag(sk, SOCK_WIFI_STATUS) && skb->wifi_acked_valid)
2156		__sock_recv_wifi_status(msg, sk, skb);
2157}
2158
2159void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2160			      struct sk_buff *skb);
2161
2162static inline void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2163					  struct sk_buff *skb)
 
2164{
2165#define FLAGS_TS_OR_DROPS ((1UL << SOCK_RXQ_OVFL)			| \
2166			   (1UL << SOCK_RCVTSTAMP)			| \
2167			   (1UL << SOCK_TIMESTAMPING_SOFTWARE)		| \
2168			   (1UL << SOCK_TIMESTAMPING_RAW_HARDWARE)	| \
2169			   (1UL << SOCK_TIMESTAMPING_SYS_HARDWARE))
 
 
 
 
 
 
 
 
 
2170
2171	if (sk->sk_flags & FLAGS_TS_OR_DROPS)
2172		__sock_recv_ts_and_drops(msg, sk, skb);
2173	else
2174		sk->sk_stamp = skb->tstamp;
2175}
2176
2177/**
2178 * sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
2179 * @sk:		socket sending this packet
2180 * @tx_flags:	filled with instructions for time stamping
2181 *
2182 * Currently only depends on SOCK_TIMESTAMPING* flags.
2183 */
2184void sock_tx_timestamp(struct sock *sk, __u8 *tx_flags);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2185
2186/**
2187 * sk_eat_skb - Release a skb if it is no longer needed
2188 * @sk: socket to eat this skb from
2189 * @skb: socket buffer to eat
2190 * @copied_early: flag indicating whether DMA operations copied this data early
2191 *
2192 * This routine must be called with interrupts disabled or with the socket
2193 * locked so that the sk_buff queue operation is ok.
2194*/
2195#ifdef CONFIG_NET_DMA
2196static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb, bool copied_early)
2197{
2198	__skb_unlink(skb, &sk->sk_receive_queue);
2199	if (!copied_early)
2200		__kfree_skb(skb);
2201	else
2202		__skb_queue_tail(&sk->sk_async_wait_queue, skb);
2203}
 
 
 
 
 
 
2204#else
2205static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb, bool copied_early)
2206{
2207	__skb_unlink(skb, &sk->sk_receive_queue);
2208	__kfree_skb(skb);
2209}
2210#endif
2211
2212static inline
2213struct net *sock_net(const struct sock *sk)
 
 
2214{
2215	return read_pnet(&sk->sk_net);
2216}
2217
2218static inline
2219void sock_net_set(struct sock *sk, struct net *net)
2220{
2221	write_pnet(&sk->sk_net, net);
 
2222}
2223
2224/*
2225 * Kernel sockets, f.e. rtnl or icmp_socket, are a part of a namespace.
2226 * They should not hold a reference to a namespace in order to allow
2227 * to stop it.
2228 * Sockets after sk_change_net should be released using sk_release_kernel
2229 */
2230static inline void sk_change_net(struct sock *sk, struct net *net)
 
2231{
2232	struct net *current_net = sock_net(sk);
 
2233
2234	if (!net_eq(current_net, net)) {
2235		put_net(current_net);
2236		sock_net_set(sk, hold_net(net));
 
 
 
2237	}
 
 
 
2238}
2239
2240static inline struct sock *skb_steal_sock(struct sk_buff *skb)
 
 
 
2241{
2242	if (skb->sk) {
2243		struct sock *sk = skb->sk;
2244
2245		skb->destructor = NULL;
2246		skb->sk = NULL;
2247		return sk;
2248	}
2249	return NULL;
 
 
 
2250}
2251
2252void sock_enable_timestamp(struct sock *sk, int flag);
2253int sock_get_timestamp(struct sock *, struct timeval __user *);
2254int sock_get_timestampns(struct sock *, struct timespec __user *);
2255int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level,
2256		       int type);
2257
2258bool sk_ns_capable(const struct sock *sk,
2259		   struct user_namespace *user_ns, int cap);
2260bool sk_capable(const struct sock *sk, int cap);
2261bool sk_net_capable(const struct sock *sk, int cap);
2262
2263/*
2264 *	Enable debug/info messages
2265 */
2266extern int net_msg_warn;
2267#define NETDEBUG(fmt, args...) \
2268	do { if (net_msg_warn) printk(fmt,##args); } while (0)
2269
2270#define LIMIT_NETDEBUG(fmt, args...) \
2271	do { if (net_msg_warn && net_ratelimit()) printk(fmt,##args); } while(0)
 
 
 
 
 
 
 
2272
2273extern __u32 sysctl_wmem_max;
2274extern __u32 sysctl_rmem_max;
2275
2276extern int sysctl_optmem_max;
2277
2278extern __u32 sysctl_wmem_default;
2279extern __u32 sysctl_rmem_default;
2280
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2281#endif	/* _SOCK_H */