v4.19.13 snapshot.
diff --git a/include/net/sock.h b/include/net/sock.h
new file mode 100644
index 0000000..f18dbd6
--- /dev/null
+++ b/include/net/sock.h
@@ -0,0 +1,2512 @@
+/*
+ * INET An implementation of the TCP/IP protocol suite for the LINUX
+ * operating system. INET is implemented using the BSD Socket
+ * interface as the means of communication with the user level.
+ *
+ * Definitions for the AF_INET socket handler.
+ *
+ * Version: @(#)sock.h 1.0.4 05/13/93
+ *
+ * Authors: Ross Biro
+ * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
+ * Corey Minyard <wf-rch!minyard@relay.EU.net>
+ * Florian La Roche <flla@stud.uni-sb.de>
+ *
+ * Fixes:
+ * Alan Cox : Volatiles in skbuff pointers. See
+ * skbuff comments. May be overdone,
+ * better to prove they can be removed
+ * than the reverse.
+ * Alan Cox : Added a zapped field for tcp to note
+ * a socket is reset and must stay shut up
+ * Alan Cox : New fields for options
+ * Pauline Middelink : identd support
+ * Alan Cox : Eliminate low level recv/recvfrom
+ * David S. Miller : New socket lookup architecture.
+ * Steve Whitehouse: Default routines for sock_ops
+ * Arnaldo C. Melo : removed net_pinfo, tp_pinfo and made
+ * protinfo be just a void pointer, as the
+ * protocol specific parts were moved to
+ * respective headers and ipv4/v6, etc now
+ * use private slabcaches for its socks
+ * Pedro Hortas : New flags field for socket options
+ *
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+#ifndef _SOCK_H
+#define _SOCK_H
+
+#include <linux/hardirq.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/list_nulls.h>
+#include <linux/timer.h>
+#include <linux/cache.h>
+#include <linux/bitops.h>
+#include <linux/lockdep.h>
+#include <linux/netdevice.h>
+#include <linux/skbuff.h> /* struct sk_buff */
+#include <linux/mm.h>
+#include <linux/security.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <linux/page_counter.h>
+#include <linux/memcontrol.h>
+#include <linux/static_key.h>
+#include <linux/sched.h>
+#include <linux/wait.h>
+#include <linux/cgroup-defs.h>
+#include <linux/rbtree.h>
+#include <linux/filter.h>
+#include <linux/rculist_nulls.h>
+#include <linux/poll.h>
+
+#include <linux/atomic.h>
+#include <linux/refcount.h>
+#include <net/dst.h>
+#include <net/checksum.h>
+#include <net/tcp_states.h>
+#include <linux/net_tstamp.h>
+#include <net/smc.h>
+#include <net/l3mdev.h>
+
+/*
+ * This structure really needs to be cleaned up.
+ * Most of it is for TCP, and not used by any of
+ * the other protocols.
+ */
+
+/* Define this to get the SOCK_DBG debugging facility. */
+#define SOCK_DEBUGGING
+#ifdef SOCK_DEBUGGING
+#define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \
+ printk(KERN_DEBUG msg); } while (0)
+#else
+/* Validate arguments and do nothing */
+static inline __printf(2, 3)
+void SOCK_DEBUG(const struct sock *sk, const char *msg, ...)
+{
+}
+#endif
+
+/* This is the per-socket lock. The spinlock provides a synchronization
+ * between user contexts and software interrupt processing, whereas the
+ * mini-semaphore synchronizes multiple users amongst themselves.
+ */
+typedef struct {
+ spinlock_t slock;
+ int owned;
+ wait_queue_head_t wq;
+ /*
+ * We express the mutex-alike socket_lock semantics
+ * to the lock validator by explicitly managing
+ * the slock as a lock variant (in addition to
+ * the slock itself):
+ */
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ struct lockdep_map dep_map;
+#endif
+} socket_lock_t;
+
+struct sock;
+struct proto;
+struct net;
+
+typedef __u32 __bitwise __portpair;
+typedef __u64 __bitwise __addrpair;
+
+/**
+ * struct sock_common - minimal network layer representation of sockets
+ * @skc_daddr: Foreign IPv4 addr
+ * @skc_rcv_saddr: Bound local IPv4 addr
+ * @skc_hash: hash value used with various protocol lookup tables
+ * @skc_u16hashes: two u16 hash values used by UDP lookup tables
+ * @skc_dport: placeholder for inet_dport/tw_dport
+ * @skc_num: placeholder for inet_num/tw_num
+ * @skc_family: network address family
+ * @skc_state: Connection state
+ * @skc_reuse: %SO_REUSEADDR setting
+ * @skc_reuseport: %SO_REUSEPORT setting
+ * @skc_bound_dev_if: bound device index if != 0
+ * @skc_bind_node: bind hash linkage for various protocol lookup tables
+ * @skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol
+ * @skc_prot: protocol handlers inside a network family
+ * @skc_net: reference to the network namespace of this socket
+ * @skc_node: main hash linkage for various protocol lookup tables
+ * @skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol
+ * @skc_tx_queue_mapping: tx queue number for this connection
+ * @skc_rx_queue_mapping: rx queue number for this connection
+ * @skc_flags: place holder for sk_flags
+ * %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE,
+ * %SO_OOBINLINE settings, %SO_TIMESTAMPING settings
+ * @skc_incoming_cpu: record/match cpu processing incoming packets
+ * @skc_refcnt: reference count
+ *
+ * This is the minimal network layer representation of sockets, the header
+ * for struct sock and struct inet_timewait_sock.
+ */
+struct sock_common {
+ /* skc_daddr and skc_rcv_saddr must be grouped on a 8 bytes aligned
+ * address on 64bit arches : cf INET_MATCH()
+ */
+ union {
+ __addrpair skc_addrpair;
+ struct {
+ __be32 skc_daddr;
+ __be32 skc_rcv_saddr;
+ };
+ };
+ union {
+ unsigned int skc_hash;
+ __u16 skc_u16hashes[2];
+ };
+ /* skc_dport && skc_num must be grouped as well */
+ union {
+ __portpair skc_portpair;
+ struct {
+ __be16 skc_dport;
+ __u16 skc_num;
+ };
+ };
+
+ unsigned short skc_family;
+ volatile unsigned char skc_state;
+ unsigned char skc_reuse:4;
+ unsigned char skc_reuseport:1;
+ unsigned char skc_ipv6only:1;
+ unsigned char skc_net_refcnt:1;
+ int skc_bound_dev_if;
+ union {
+ struct hlist_node skc_bind_node;
+ struct hlist_node skc_portaddr_node;
+ };
+ struct proto *skc_prot;
+ possible_net_t skc_net;
+
+#if IS_ENABLED(CONFIG_IPV6)
+ struct in6_addr skc_v6_daddr;
+ struct in6_addr skc_v6_rcv_saddr;
+#endif
+
+ atomic64_t skc_cookie;
+
+ /* following fields are padding to force
+ * offset(struct sock, sk_refcnt) == 128 on 64bit arches
+ * assuming IPV6 is enabled. We use this padding differently
+ * for different kind of 'sockets'
+ */
+ union {
+ unsigned long skc_flags;
+ struct sock *skc_listener; /* request_sock */
+ struct inet_timewait_death_row *skc_tw_dr; /* inet_timewait_sock */
+ };
+ /*
+ * fields between dontcopy_begin/dontcopy_end
+ * are not copied in sock_copy()
+ */
+ /* private: */
+ int skc_dontcopy_begin[0];
+ /* public: */
+ union {
+ struct hlist_node skc_node;
+ struct hlist_nulls_node skc_nulls_node;
+ };
+ unsigned short skc_tx_queue_mapping;
+#ifdef CONFIG_XPS
+ unsigned short skc_rx_queue_mapping;
+#endif
+ union {
+ int skc_incoming_cpu;
+ u32 skc_rcv_wnd;
+ u32 skc_tw_rcv_nxt; /* struct tcp_timewait_sock */
+ };
+
+ refcount_t skc_refcnt;
+ /* private: */
+ int skc_dontcopy_end[0];
+ union {
+ u32 skc_rxhash;
+ u32 skc_window_clamp;
+ u32 skc_tw_snd_nxt; /* struct tcp_timewait_sock */
+ };
+ /* public: */
+};
+
+/**
+ * struct sock - network layer representation of sockets
+ * @__sk_common: shared layout with inet_timewait_sock
+ * @sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
+ * @sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
+ * @sk_lock: synchronizer
+ * @sk_kern_sock: True if sock is using kernel lock classes
+ * @sk_rcvbuf: size of receive buffer in bytes
+ * @sk_wq: sock wait queue and async head
+ * @sk_rx_dst: receive input route used by early demux
+ * @sk_dst_cache: destination cache
+ * @sk_dst_pending_confirm: need to confirm neighbour
+ * @sk_policy: flow policy
+ * @sk_receive_queue: incoming packets
+ * @sk_wmem_alloc: transmit queue bytes committed
+ * @sk_tsq_flags: TCP Small Queues flags
+ * @sk_write_queue: Packet sending queue
+ * @sk_omem_alloc: "o" is "option" or "other"
+ * @sk_wmem_queued: persistent queue size
+ * @sk_forward_alloc: space allocated forward
+ * @sk_napi_id: id of the last napi context to receive data for sk
+ * @sk_ll_usec: usecs to busypoll when there is no data
+ * @sk_allocation: allocation mode
+ * @sk_pacing_rate: Pacing rate (if supported by transport/packet scheduler)
+ * @sk_pacing_status: Pacing status (requested, handled by sch_fq)
+ * @sk_max_pacing_rate: Maximum pacing rate (%SO_MAX_PACING_RATE)
+ * @sk_sndbuf: size of send buffer in bytes
+ * @__sk_flags_offset: empty field used to determine location of bitfield
+ * @sk_padding: unused element for alignment
+ * @sk_no_check_tx: %SO_NO_CHECK setting, set checksum in TX packets
+ * @sk_no_check_rx: allow zero checksum in RX packets
+ * @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
+ * @sk_route_nocaps: forbidden route capabilities (e.g NETIF_F_GSO_MASK)
+ * @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
+ * @sk_gso_max_size: Maximum GSO segment size to build
+ * @sk_gso_max_segs: Maximum number of GSO segments
+ * @sk_pacing_shift: scaling factor for TCP Small Queues
+ * @sk_lingertime: %SO_LINGER l_linger setting
+ * @sk_backlog: always used with the per-socket spinlock held
+ * @sk_callback_lock: used with the callbacks in the end of this struct
+ * @sk_error_queue: rarely used
+ * @sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt,
+ * IPV6_ADDRFORM for instance)
+ * @sk_err: last error
+ * @sk_err_soft: errors that don't cause failure but are the cause of a
+ * persistent failure not just 'timed out'
+ * @sk_drops: raw/udp drops counter
+ * @sk_ack_backlog: current listen backlog
+ * @sk_max_ack_backlog: listen backlog set in listen()
+ * @sk_uid: user id of owner
+ * @sk_priority: %SO_PRIORITY setting
+ * @sk_type: socket type (%SOCK_STREAM, etc)
+ * @sk_protocol: which protocol this socket belongs in this network family
+ * @sk_peer_pid: &struct pid for this socket's peer
+ * @sk_peer_cred: %SO_PEERCRED setting
+ * @sk_rcvlowat: %SO_RCVLOWAT setting
+ * @sk_rcvtimeo: %SO_RCVTIMEO setting
+ * @sk_sndtimeo: %SO_SNDTIMEO setting
+ * @sk_txhash: computed flow hash for use on transmit
+ * @sk_filter: socket filtering instructions
+ * @sk_timer: sock cleanup timer
+ * @sk_stamp: time stamp of last packet received
+ * @sk_tsflags: SO_TIMESTAMPING socket options
+ * @sk_tskey: counter to disambiguate concurrent tstamp requests
+ * @sk_zckey: counter to order MSG_ZEROCOPY notifications
+ * @sk_socket: Identd and reporting IO signals
+ * @sk_user_data: RPC layer private data
+ * @sk_frag: cached page frag
+ * @sk_peek_off: current peek_offset value
+ * @sk_send_head: front of stuff to transmit
+ * @sk_security: used by security modules
+ * @sk_mark: generic packet mark
+ * @sk_cgrp_data: cgroup data for this cgroup
+ * @sk_memcg: this socket's memory cgroup association
+ * @sk_write_pending: a write to stream socket waits to start
+ * @sk_state_change: callback to indicate change in the state of the sock
+ * @sk_data_ready: callback to indicate there is data to be processed
+ * @sk_write_space: callback to indicate there is bf sending space available
+ * @sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
+ * @sk_backlog_rcv: callback to process the backlog
+ * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
+ * @sk_reuseport_cb: reuseport group container
+ * @sk_rcu: used during RCU grace period
+ * @sk_clockid: clockid used by time-based scheduling (SO_TXTIME)
+ * @sk_txtime_deadline_mode: set deadline mode for SO_TXTIME
+ * @sk_txtime_unused: unused txtime flags
+ */
+struct sock {
+ /*
+ * Now struct inet_timewait_sock also uses sock_common, so please just
+ * don't add nothing before this first member (__sk_common) --acme
+ */
+ struct sock_common __sk_common;
+#define sk_node __sk_common.skc_node
+#define sk_nulls_node __sk_common.skc_nulls_node
+#define sk_refcnt __sk_common.skc_refcnt
+#define sk_tx_queue_mapping __sk_common.skc_tx_queue_mapping
+#ifdef CONFIG_XPS
+#define sk_rx_queue_mapping __sk_common.skc_rx_queue_mapping
+#endif
+
+#define sk_dontcopy_begin __sk_common.skc_dontcopy_begin
+#define sk_dontcopy_end __sk_common.skc_dontcopy_end
+#define sk_hash __sk_common.skc_hash
+#define sk_portpair __sk_common.skc_portpair
+#define sk_num __sk_common.skc_num
+#define sk_dport __sk_common.skc_dport
+#define sk_addrpair __sk_common.skc_addrpair
+#define sk_daddr __sk_common.skc_daddr
+#define sk_rcv_saddr __sk_common.skc_rcv_saddr
+#define sk_family __sk_common.skc_family
+#define sk_state __sk_common.skc_state
+#define sk_reuse __sk_common.skc_reuse
+#define sk_reuseport __sk_common.skc_reuseport
+#define sk_ipv6only __sk_common.skc_ipv6only
+#define sk_net_refcnt __sk_common.skc_net_refcnt
+#define sk_bound_dev_if __sk_common.skc_bound_dev_if
+#define sk_bind_node __sk_common.skc_bind_node
+#define sk_prot __sk_common.skc_prot
+#define sk_net __sk_common.skc_net
+#define sk_v6_daddr __sk_common.skc_v6_daddr
+#define sk_v6_rcv_saddr __sk_common.skc_v6_rcv_saddr
+#define sk_cookie __sk_common.skc_cookie
+#define sk_incoming_cpu __sk_common.skc_incoming_cpu
+#define sk_flags __sk_common.skc_flags
+#define sk_rxhash __sk_common.skc_rxhash
+
+ socket_lock_t sk_lock;
+ atomic_t sk_drops;
+ int sk_rcvlowat;
+ struct sk_buff_head sk_error_queue;
+ struct sk_buff_head sk_receive_queue;
+ /*
+ * The backlog queue is special, it is always used with
+ * the per-socket spinlock held and requires low latency
+ * access. Therefore we special case it's implementation.
+ * Note : rmem_alloc is in this structure to fill a hole
+ * on 64bit arches, not because its logically part of
+ * backlog.
+ */
+ struct {
+ atomic_t rmem_alloc;
+ int len;
+ struct sk_buff *head;
+ struct sk_buff *tail;
+ } sk_backlog;
+#define sk_rmem_alloc sk_backlog.rmem_alloc
+
+ int sk_forward_alloc;
+#ifdef CONFIG_NET_RX_BUSY_POLL
+ unsigned int sk_ll_usec;
+ /* ===== mostly read cache line ===== */
+ unsigned int sk_napi_id;
+#endif
+ int sk_rcvbuf;
+
+ struct sk_filter __rcu *sk_filter;
+ union {
+ struct socket_wq __rcu *sk_wq;
+ struct socket_wq *sk_wq_raw;
+ };
+#ifdef CONFIG_XFRM
+ struct xfrm_policy __rcu *sk_policy[2];
+#endif
+ struct dst_entry *sk_rx_dst;
+ struct dst_entry __rcu *sk_dst_cache;
+ atomic_t sk_omem_alloc;
+ int sk_sndbuf;
+
+ /* ===== cache line for TX ===== */
+ int sk_wmem_queued;
+ refcount_t sk_wmem_alloc;
+ unsigned long sk_tsq_flags;
+ union {
+ struct sk_buff *sk_send_head;
+ struct rb_root tcp_rtx_queue;
+ };
+ struct sk_buff_head sk_write_queue;
+ __s32 sk_peek_off;
+ int sk_write_pending;
+ __u32 sk_dst_pending_confirm;
+ u32 sk_pacing_status; /* see enum sk_pacing */
+ long sk_sndtimeo;
+ struct timer_list sk_timer;
+ __u32 sk_priority;
+ __u32 sk_mark;
+ u32 sk_pacing_rate; /* bytes per second */
+ u32 sk_max_pacing_rate;
+ struct page_frag sk_frag;
+ netdev_features_t sk_route_caps;
+ netdev_features_t sk_route_nocaps;
+ netdev_features_t sk_route_forced_caps;
+ int sk_gso_type;
+ unsigned int sk_gso_max_size;
+ gfp_t sk_allocation;
+ __u32 sk_txhash;
+
+ /*
+ * Because of non atomicity rules, all
+ * changes are protected by socket lock.
+ */
+ unsigned int __sk_flags_offset[0];
+#ifdef __BIG_ENDIAN_BITFIELD
+#define SK_FL_PROTO_SHIFT 16
+#define SK_FL_PROTO_MASK 0x00ff0000
+
+#define SK_FL_TYPE_SHIFT 0
+#define SK_FL_TYPE_MASK 0x0000ffff
+#else
+#define SK_FL_PROTO_SHIFT 8
+#define SK_FL_PROTO_MASK 0x0000ff00
+
+#define SK_FL_TYPE_SHIFT 16
+#define SK_FL_TYPE_MASK 0xffff0000
+#endif
+
+ unsigned int sk_padding : 1,
+ sk_kern_sock : 1,
+ sk_no_check_tx : 1,
+ sk_no_check_rx : 1,
+ sk_userlocks : 4,
+ sk_protocol : 8,
+ sk_type : 16;
+#define SK_PROTOCOL_MAX U8_MAX
+ u16 sk_gso_max_segs;
+ u8 sk_pacing_shift;
+ unsigned long sk_lingertime;
+ struct proto *sk_prot_creator;
+ rwlock_t sk_callback_lock;
+ int sk_err,
+ sk_err_soft;
+ u32 sk_ack_backlog;
+ u32 sk_max_ack_backlog;
+ kuid_t sk_uid;
+ struct pid *sk_peer_pid;
+ const struct cred *sk_peer_cred;
+ long sk_rcvtimeo;
+ ktime_t sk_stamp;
+ u16 sk_tsflags;
+ u8 sk_shutdown;
+ u32 sk_tskey;
+ atomic_t sk_zckey;
+
+ u8 sk_clockid;
+ u8 sk_txtime_deadline_mode : 1,
+ sk_txtime_report_errors : 1,
+ sk_txtime_unused : 6;
+
+ struct socket *sk_socket;
+ void *sk_user_data;
+#ifdef CONFIG_SECURITY
+ void *sk_security;
+#endif
+ struct sock_cgroup_data sk_cgrp_data;
+ struct mem_cgroup *sk_memcg;
+ void (*sk_state_change)(struct sock *sk);
+ void (*sk_data_ready)(struct sock *sk);
+ void (*sk_write_space)(struct sock *sk);
+ void (*sk_error_report)(struct sock *sk);
+ int (*sk_backlog_rcv)(struct sock *sk,
+ struct sk_buff *skb);
+#ifdef CONFIG_SOCK_VALIDATE_XMIT
+ struct sk_buff* (*sk_validate_xmit_skb)(struct sock *sk,
+ struct net_device *dev,
+ struct sk_buff *skb);
+#endif
+ void (*sk_destruct)(struct sock *sk);
+ struct sock_reuseport __rcu *sk_reuseport_cb;
+ struct rcu_head sk_rcu;
+};
+
+enum sk_pacing {
+ SK_PACING_NONE = 0,
+ SK_PACING_NEEDED = 1,
+ SK_PACING_FQ = 2,
+};
+
+#define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data)))
+
+#define rcu_dereference_sk_user_data(sk) rcu_dereference(__sk_user_data((sk)))
+#define rcu_assign_sk_user_data(sk, ptr) rcu_assign_pointer(__sk_user_data((sk)), ptr)
+
+/*
+ * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK
+ * or not whether his port will be reused by someone else. SK_FORCE_REUSE
+ * on a socket means that the socket will reuse everybody else's port
+ * without looking at the other's sk_reuse value.
+ */
+
+#define SK_NO_REUSE 0
+#define SK_CAN_REUSE 1
+#define SK_FORCE_REUSE 2
+
+int sk_set_peek_off(struct sock *sk, int val);
+
+static inline int sk_peek_offset(struct sock *sk, int flags)
+{
+ if (unlikely(flags & MSG_PEEK)) {
+ return READ_ONCE(sk->sk_peek_off);
+ }
+
+ return 0;
+}
+
+static inline void sk_peek_offset_bwd(struct sock *sk, int val)
+{
+ s32 off = READ_ONCE(sk->sk_peek_off);
+
+ if (unlikely(off >= 0)) {
+ off = max_t(s32, off - val, 0);
+ WRITE_ONCE(sk->sk_peek_off, off);
+ }
+}
+
+static inline void sk_peek_offset_fwd(struct sock *sk, int val)
+{
+ sk_peek_offset_bwd(sk, -val);
+}
+
+/*
+ * Hashed lists helper routines
+ */
+static inline struct sock *sk_entry(const struct hlist_node *node)
+{
+ return hlist_entry(node, struct sock, sk_node);
+}
+
+static inline struct sock *__sk_head(const struct hlist_head *head)
+{
+ return hlist_entry(head->first, struct sock, sk_node);
+}
+
+static inline struct sock *sk_head(const struct hlist_head *head)
+{
+ return hlist_empty(head) ? NULL : __sk_head(head);
+}
+
+static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head)
+{
+ return hlist_nulls_entry(head->first, struct sock, sk_nulls_node);
+}
+
+static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head)
+{
+ return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head);
+}
+
+static inline struct sock *sk_next(const struct sock *sk)
+{
+ return hlist_entry_safe(sk->sk_node.next, struct sock, sk_node);
+}
+
+static inline struct sock *sk_nulls_next(const struct sock *sk)
+{
+ return (!is_a_nulls(sk->sk_nulls_node.next)) ?
+ hlist_nulls_entry(sk->sk_nulls_node.next,
+ struct sock, sk_nulls_node) :
+ NULL;
+}
+
+static inline bool sk_unhashed(const struct sock *sk)
+{
+ return hlist_unhashed(&sk->sk_node);
+}
+
+static inline bool sk_hashed(const struct sock *sk)
+{
+ return !sk_unhashed(sk);
+}
+
+static inline void sk_node_init(struct hlist_node *node)
+{
+ node->pprev = NULL;
+}
+
+static inline void sk_nulls_node_init(struct hlist_nulls_node *node)
+{
+ node->pprev = NULL;
+}
+
+static inline void __sk_del_node(struct sock *sk)
+{
+ __hlist_del(&sk->sk_node);
+}
+
+/* NB: equivalent to hlist_del_init_rcu */
+static inline bool __sk_del_node_init(struct sock *sk)
+{
+ if (sk_hashed(sk)) {
+ __sk_del_node(sk);
+ sk_node_init(&sk->sk_node);
+ return true;
+ }
+ return false;
+}
+
+/* Grab socket reference count. This operation is valid only
+ when sk is ALREADY grabbed f.e. it is found in hash table
+ or a list and the lookup is made under lock preventing hash table
+ modifications.
+ */
+
+static __always_inline void sock_hold(struct sock *sk)
+{
+ refcount_inc(&sk->sk_refcnt);
+}
+
+/* Ungrab socket in the context, which assumes that socket refcnt
+ cannot hit zero, f.e. it is true in context of any socketcall.
+ */
+static __always_inline void __sock_put(struct sock *sk)
+{
+ refcount_dec(&sk->sk_refcnt);
+}
+
+static inline bool sk_del_node_init(struct sock *sk)
+{
+ bool rc = __sk_del_node_init(sk);
+
+ if (rc) {
+ /* paranoid for a while -acme */
+ WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
+ __sock_put(sk);
+ }
+ return rc;
+}
+#define sk_del_node_init_rcu(sk) sk_del_node_init(sk)
+
+static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk)
+{
+ if (sk_hashed(sk)) {
+ hlist_nulls_del_init_rcu(&sk->sk_nulls_node);
+ return true;
+ }
+ return false;
+}
+
+static inline bool sk_nulls_del_node_init_rcu(struct sock *sk)
+{
+ bool rc = __sk_nulls_del_node_init_rcu(sk);
+
+ if (rc) {
+ /* paranoid for a while -acme */
+ WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
+ __sock_put(sk);
+ }
+ return rc;
+}
+
+static inline void __sk_add_node(struct sock *sk, struct hlist_head *list)
+{
+ hlist_add_head(&sk->sk_node, list);
+}
+
+static inline void sk_add_node(struct sock *sk, struct hlist_head *list)
+{
+ sock_hold(sk);
+ __sk_add_node(sk, list);
+}
+
+static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list)
+{
+ sock_hold(sk);
+ if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport &&
+ sk->sk_family == AF_INET6)
+ hlist_add_tail_rcu(&sk->sk_node, list);
+ else
+ hlist_add_head_rcu(&sk->sk_node, list);
+}
+
+static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
+{
+ hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list);
+}
+
+static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
+{
+ sock_hold(sk);
+ __sk_nulls_add_node_rcu(sk, list);
+}
+
+static inline void __sk_del_bind_node(struct sock *sk)
+{
+ __hlist_del(&sk->sk_bind_node);
+}
+
+static inline void sk_add_bind_node(struct sock *sk,
+ struct hlist_head *list)
+{
+ hlist_add_head(&sk->sk_bind_node, list);
+}
+
+#define sk_for_each(__sk, list) \
+ hlist_for_each_entry(__sk, list, sk_node)
+#define sk_for_each_rcu(__sk, list) \
+ hlist_for_each_entry_rcu(__sk, list, sk_node)
+#define sk_nulls_for_each(__sk, node, list) \
+ hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)
+#define sk_nulls_for_each_rcu(__sk, node, list) \
+ hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)
+#define sk_for_each_from(__sk) \
+ hlist_for_each_entry_from(__sk, sk_node)
+#define sk_nulls_for_each_from(__sk, node) \
+ if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \
+ hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node)
+#define sk_for_each_safe(__sk, tmp, list) \
+ hlist_for_each_entry_safe(__sk, tmp, list, sk_node)
+#define sk_for_each_bound(__sk, list) \
+ hlist_for_each_entry(__sk, list, sk_bind_node)
+
+/**
+ * sk_for_each_entry_offset_rcu - iterate over a list at a given struct offset
+ * @tpos: the type * to use as a loop cursor.
+ * @pos: the &struct hlist_node to use as a loop cursor.
+ * @head: the head for your list.
+ * @offset: offset of hlist_node within the struct.
+ *
+ */
+#define sk_for_each_entry_offset_rcu(tpos, pos, head, offset) \
+ for (pos = rcu_dereference(hlist_first_rcu(head)); \
+ pos != NULL && \
+ ({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;}); \
+ pos = rcu_dereference(hlist_next_rcu(pos)))
+
+static inline struct user_namespace *sk_user_ns(struct sock *sk)
+{
+ /* Careful only use this in a context where these parameters
+ * can not change and must all be valid, such as recvmsg from
+ * userspace.
+ */
+ return sk->sk_socket->file->f_cred->user_ns;
+}
+
+/* Sock flags */
+enum sock_flags {
+ SOCK_DEAD,
+ SOCK_DONE,
+ SOCK_URGINLINE,
+ SOCK_KEEPOPEN,
+ SOCK_LINGER,
+ SOCK_DESTROY,
+ SOCK_BROADCAST,
+ SOCK_TIMESTAMP,
+ SOCK_ZAPPED,
+ SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */
+ SOCK_DBG, /* %SO_DEBUG setting */
+ SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
+ SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */
+ SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
+ SOCK_QUEUE_SHRUNK, /* write queue has been shrunk recently */
+ SOCK_MEMALLOC, /* VM depends on this socket for swapping */
+ SOCK_TIMESTAMPING_RX_SOFTWARE, /* %SOF_TIMESTAMPING_RX_SOFTWARE */
+ SOCK_FASYNC, /* fasync() active */
+ SOCK_RXQ_OVFL,
+ SOCK_ZEROCOPY, /* buffers from userspace */
+ SOCK_WIFI_STATUS, /* push wifi status to userspace */
+ SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS.
+ * Will use last 4 bytes of packet sent from
+ * user-space instead.
+ */
+ SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */
+ SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */
+ SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */
+ SOCK_TXTIME,
+};
+
+#define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))
+
+static inline void sock_copy_flags(struct sock *nsk, struct sock *osk)
+{
+ nsk->sk_flags = osk->sk_flags;
+}
+
+static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
+{
+ __set_bit(flag, &sk->sk_flags);
+}
+
+static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag)
+{
+ __clear_bit(flag, &sk->sk_flags);
+}
+
+static inline bool sock_flag(const struct sock *sk, enum sock_flags flag)
+{
+ return test_bit(flag, &sk->sk_flags);
+}
+
+#ifdef CONFIG_NET
+DECLARE_STATIC_KEY_FALSE(memalloc_socks_key);
+static inline int sk_memalloc_socks(void)
+{
+ return static_branch_unlikely(&memalloc_socks_key);
+}
+#else
+
+static inline int sk_memalloc_socks(void)
+{
+ return 0;
+}
+
+#endif
+
+static inline gfp_t sk_gfp_mask(const struct sock *sk, gfp_t gfp_mask)
+{
+ return gfp_mask | (sk->sk_allocation & __GFP_MEMALLOC);
+}
+
+static inline void sk_acceptq_removed(struct sock *sk)
+{
+ sk->sk_ack_backlog--;
+}
+
+static inline void sk_acceptq_added(struct sock *sk)
+{
+ sk->sk_ack_backlog++;
+}
+
+static inline bool sk_acceptq_is_full(const struct sock *sk)
+{
+ return sk->sk_ack_backlog > sk->sk_max_ack_backlog;
+}
+
+/*
+ * Compute minimal free write space needed to queue new packets.
+ */
+static inline int sk_stream_min_wspace(const struct sock *sk)
+{
+ return sk->sk_wmem_queued >> 1;
+}
+
+static inline int sk_stream_wspace(const struct sock *sk)
+{
+ return sk->sk_sndbuf - sk->sk_wmem_queued;
+}
+
+void sk_stream_write_space(struct sock *sk);
+
+/* OOB backlog add */
+static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
+{
+ /* dont let skb dst not refcounted, we are going to leave rcu lock */
+ skb_dst_force(skb);
+
+ if (!sk->sk_backlog.tail)
+ sk->sk_backlog.head = skb;
+ else
+ sk->sk_backlog.tail->next = skb;
+
+ sk->sk_backlog.tail = skb;
+ skb->next = NULL;
+}
+
+/*
+ * Take into account size of receive queue and backlog queue
+ * Do not take into account this skb truesize,
+ * to allow even a single big packet to come.
+ */
+static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit)
+{
+ unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc);
+
+ return qsize > limit;
+}
+
+/* The per-socket spinlock must be held here. */
+static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb,
+ unsigned int limit)
+{
+ if (sk_rcvqueues_full(sk, limit))
+ return -ENOBUFS;
+
+ /*
+ * If the skb was allocated from pfmemalloc reserves, only
+ * allow SOCK_MEMALLOC sockets to use it as this socket is
+ * helping free memory
+ */
+ if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC))
+ return -ENOMEM;
+
+ __sk_add_backlog(sk, skb);
+ sk->sk_backlog.len += skb->truesize;
+ return 0;
+}
+
+int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb);
+
+static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
+{
+ if (sk_memalloc_socks() && skb_pfmemalloc(skb))
+ return __sk_backlog_rcv(sk, skb);
+
+ return sk->sk_backlog_rcv(sk, skb);
+}
+
+static inline void sk_incoming_cpu_update(struct sock *sk)
+{
+ int cpu = raw_smp_processor_id();
+
+ if (unlikely(sk->sk_incoming_cpu != cpu))
+ sk->sk_incoming_cpu = cpu;
+}
+
+static inline void sock_rps_record_flow_hash(__u32 hash)
+{
+#ifdef CONFIG_RPS
+ struct rps_sock_flow_table *sock_flow_table;
+
+ rcu_read_lock();
+ sock_flow_table = rcu_dereference(rps_sock_flow_table);
+ rps_record_sock_flow(sock_flow_table, hash);
+ rcu_read_unlock();
+#endif
+}
+
+static inline void sock_rps_record_flow(const struct sock *sk)
+{
+#ifdef CONFIG_RPS
+ if (static_key_false(&rfs_needed)) {
+ /* Reading sk->sk_rxhash might incur an expensive cache line
+ * miss.
+ *
+ * TCP_ESTABLISHED does cover almost all states where RFS
+ * might be useful, and is cheaper [1] than testing :
+ * IPv4: inet_sk(sk)->inet_daddr
+ * IPv6: ipv6_addr_any(&sk->sk_v6_daddr)
+ * OR an additional socket flag
+ * [1] : sk_state and sk_prot are in the same cache line.
+ */
+ if (sk->sk_state == TCP_ESTABLISHED)
+ sock_rps_record_flow_hash(sk->sk_rxhash);
+ }
+#endif
+}
+
+static inline void sock_rps_save_rxhash(struct sock *sk,
+ const struct sk_buff *skb)
+{
+#ifdef CONFIG_RPS
+ if (unlikely(sk->sk_rxhash != skb->hash))
+ sk->sk_rxhash = skb->hash;
+#endif
+}
+
+static inline void sock_rps_reset_rxhash(struct sock *sk)
+{
+#ifdef CONFIG_RPS
+ sk->sk_rxhash = 0;
+#endif
+}
+
+#define sk_wait_event(__sk, __timeo, __condition, __wait) \
+ ({ int __rc; \
+ release_sock(__sk); \
+ __rc = __condition; \
+ if (!__rc) { \
+ *(__timeo) = wait_woken(__wait, \
+ TASK_INTERRUPTIBLE, \
+ *(__timeo)); \
+ } \
+ sched_annotate_sleep(); \
+ lock_sock(__sk); \
+ __rc = __condition; \
+ __rc; \
+ })
+
+int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
+int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
+void sk_stream_wait_close(struct sock *sk, long timeo_p);
+int sk_stream_error(struct sock *sk, int flags, int err);
+void sk_stream_kill_queues(struct sock *sk);
+void sk_set_memalloc(struct sock *sk);
+void sk_clear_memalloc(struct sock *sk);
+
+void __sk_flush_backlog(struct sock *sk);
+
+static inline bool sk_flush_backlog(struct sock *sk)
+{
+ if (unlikely(READ_ONCE(sk->sk_backlog.tail))) {
+ __sk_flush_backlog(sk);
+ return true;
+ }
+ return false;
+}
+
+int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb);
+
+struct request_sock_ops;
+struct timewait_sock_ops;
+struct inet_hashinfo;
+struct raw_hashinfo;
+struct smc_hashinfo;
+struct module;
+
+/*
+ * caches using SLAB_TYPESAFE_BY_RCU should let .next pointer from nulls nodes
+ * un-modified. Special care is taken when initializing object to zero.
+ */
+static inline void sk_prot_clear_nulls(struct sock *sk, int size)
+{
+ if (offsetof(struct sock, sk_node.next) != 0)
+ memset(sk, 0, offsetof(struct sock, sk_node.next));
+ memset(&sk->sk_node.pprev, 0,
+ size - offsetof(struct sock, sk_node.pprev));
+}
+
+/* Networking protocol blocks we attach to sockets.
+ * socket layer -> transport layer interface
+ */
+struct proto {
+ void (*close)(struct sock *sk,
+ long timeout);
+ int (*pre_connect)(struct sock *sk,
+ struct sockaddr *uaddr,
+ int addr_len);
+ int (*connect)(struct sock *sk,
+ struct sockaddr *uaddr,
+ int addr_len);
+ int (*disconnect)(struct sock *sk, int flags);
+
+ struct sock * (*accept)(struct sock *sk, int flags, int *err,
+ bool kern);
+
+ int (*ioctl)(struct sock *sk, int cmd,
+ unsigned long arg);
+ int (*init)(struct sock *sk);
+ void (*destroy)(struct sock *sk);
+ void (*shutdown)(struct sock *sk, int how);
+ int (*setsockopt)(struct sock *sk, int level,
+ int optname, char __user *optval,
+ unsigned int optlen);
+ int (*getsockopt)(struct sock *sk, int level,
+ int optname, char __user *optval,
+ int __user *option);
+ void (*keepalive)(struct sock *sk, int valbool);
+#ifdef CONFIG_COMPAT
+ int (*compat_setsockopt)(struct sock *sk,
+ int level,
+ int optname, char __user *optval,
+ unsigned int optlen);
+ int (*compat_getsockopt)(struct sock *sk,
+ int level,
+ int optname, char __user *optval,
+ int __user *option);
+ int (*compat_ioctl)(struct sock *sk,
+ unsigned int cmd, unsigned long arg);
+#endif
+ int (*sendmsg)(struct sock *sk, struct msghdr *msg,
+ size_t len);
+ int (*recvmsg)(struct sock *sk, struct msghdr *msg,
+ size_t len, int noblock, int flags,
+ int *addr_len);
+ int (*sendpage)(struct sock *sk, struct page *page,
+ int offset, size_t size, int flags);
+ int (*bind)(struct sock *sk,
+ struct sockaddr *uaddr, int addr_len);
+
+ int (*backlog_rcv) (struct sock *sk,
+ struct sk_buff *skb);
+
+ void (*release_cb)(struct sock *sk);
+
+ /* Keeping track of sk's, looking them up, and port selection methods. */
+ int (*hash)(struct sock *sk);
+ void (*unhash)(struct sock *sk);
+ void (*rehash)(struct sock *sk);
+ int (*get_port)(struct sock *sk, unsigned short snum);
+
+ /* Keeping track of sockets in use */
+#ifdef CONFIG_PROC_FS
+ unsigned int inuse_idx;
+#endif
+
+ bool (*stream_memory_free)(const struct sock *sk);
+ bool (*stream_memory_read)(const struct sock *sk);
+ /* Memory pressure */
+ void (*enter_memory_pressure)(struct sock *sk);
+ void (*leave_memory_pressure)(struct sock *sk);
+ atomic_long_t *memory_allocated; /* Current allocated memory. */
+ struct percpu_counter *sockets_allocated; /* Current number of sockets. */
+ /*
+ * Pressure flag: try to collapse.
+ * Technical note: it is used by multiple contexts non atomically.
+ * All the __sk_mem_schedule() is of this nature: accounting
+ * is strict, actions are advisory and have some latency.
+ */
+ unsigned long *memory_pressure;
+ long *sysctl_mem;
+
+ int *sysctl_wmem;
+ int *sysctl_rmem;
+ u32 sysctl_wmem_offset;
+ u32 sysctl_rmem_offset;
+
+ int max_header;
+ bool no_autobind;
+
+ struct kmem_cache *slab;
+ unsigned int obj_size;
+ slab_flags_t slab_flags;
+ unsigned int useroffset; /* Usercopy region offset */
+ unsigned int usersize; /* Usercopy region size */
+
+ struct percpu_counter *orphan_count;
+
+ struct request_sock_ops *rsk_prot;
+ struct timewait_sock_ops *twsk_prot;
+
+ union {
+ struct inet_hashinfo *hashinfo;
+ struct udp_table *udp_table;
+ struct raw_hashinfo *raw_hash;
+ struct smc_hashinfo *smc_hash;
+ } h;
+
+ struct module *owner;
+
+ char name[32];
+
+ struct list_head node;
+#ifdef SOCK_REFCNT_DEBUG
+ atomic_t socks;
+#endif
+ int (*diag_destroy)(struct sock *sk, int err);
+} __randomize_layout;
+
+int proto_register(struct proto *prot, int alloc_slab);
+void proto_unregister(struct proto *prot);
+int sock_load_diag_module(int family, int protocol);
+
+#ifdef SOCK_REFCNT_DEBUG
+static inline void sk_refcnt_debug_inc(struct sock *sk)
+{
+ atomic_inc(&sk->sk_prot->socks);
+}
+
+static inline void sk_refcnt_debug_dec(struct sock *sk)
+{
+ atomic_dec(&sk->sk_prot->socks);
+ printk(KERN_DEBUG "%s socket %p released, %d are still alive\n",
+ sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks));
+}
+
+static inline void sk_refcnt_debug_release(const struct sock *sk)
+{
+ if (refcount_read(&sk->sk_refcnt) != 1)
+ printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n",
+ sk->sk_prot->name, sk, refcount_read(&sk->sk_refcnt));
+}
+#else /* SOCK_REFCNT_DEBUG */
+#define sk_refcnt_debug_inc(sk) do { } while (0)
+#define sk_refcnt_debug_dec(sk) do { } while (0)
+#define sk_refcnt_debug_release(sk) do { } while (0)
+#endif /* SOCK_REFCNT_DEBUG */
+
+static inline bool sk_stream_memory_free(const struct sock *sk)
+{
+ if (sk->sk_wmem_queued >= sk->sk_sndbuf)
+ return false;
+
+ return sk->sk_prot->stream_memory_free ?
+ sk->sk_prot->stream_memory_free(sk) : true;
+}
+
+static inline bool sk_stream_is_writeable(const struct sock *sk)
+{
+ return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) &&
+ sk_stream_memory_free(sk);
+}
+
+static inline int sk_under_cgroup_hierarchy(struct sock *sk,
+ struct cgroup *ancestor)
+{
+#ifdef CONFIG_SOCK_CGROUP_DATA
+ return cgroup_is_descendant(sock_cgroup_ptr(&sk->sk_cgrp_data),
+ ancestor);
+#else
+ return -ENOTSUPP;
+#endif
+}
+
+static inline bool sk_has_memory_pressure(const struct sock *sk)
+{
+ return sk->sk_prot->memory_pressure != NULL;
+}
+
+static inline bool sk_under_memory_pressure(const struct sock *sk)
+{
+ if (!sk->sk_prot->memory_pressure)
+ return false;
+
+ if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
+ mem_cgroup_under_socket_pressure(sk->sk_memcg))
+ return true;
+
+ return !!*sk->sk_prot->memory_pressure;
+}
+
+static inline long
+sk_memory_allocated(const struct sock *sk)
+{
+ return atomic_long_read(sk->sk_prot->memory_allocated);
+}
+
+static inline long
+sk_memory_allocated_add(struct sock *sk, int amt)
+{
+ return atomic_long_add_return(amt, sk->sk_prot->memory_allocated);
+}
+
+static inline void
+sk_memory_allocated_sub(struct sock *sk, int amt)
+{
+ atomic_long_sub(amt, sk->sk_prot->memory_allocated);
+}
+
+static inline void sk_sockets_allocated_dec(struct sock *sk)
+{
+ percpu_counter_dec(sk->sk_prot->sockets_allocated);
+}
+
+static inline void sk_sockets_allocated_inc(struct sock *sk)
+{
+ percpu_counter_inc(sk->sk_prot->sockets_allocated);
+}
+
+static inline int
+sk_sockets_allocated_read_positive(struct sock *sk)
+{
+ return percpu_counter_read_positive(sk->sk_prot->sockets_allocated);
+}
+
+static inline int
+proto_sockets_allocated_sum_positive(struct proto *prot)
+{
+ return percpu_counter_sum_positive(prot->sockets_allocated);
+}
+
+static inline long
+proto_memory_allocated(struct proto *prot)
+{
+ return atomic_long_read(prot->memory_allocated);
+}
+
+static inline bool
+proto_memory_pressure(struct proto *prot)
+{
+ if (!prot->memory_pressure)
+ return false;
+ return !!*prot->memory_pressure;
+}
+
+
+#ifdef CONFIG_PROC_FS
+/* Called with local bh disabled */
+void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc);
+int sock_prot_inuse_get(struct net *net, struct proto *proto);
+int sock_inuse_get(struct net *net);
+#else
+static inline void sock_prot_inuse_add(struct net *net, struct proto *prot,
+ int inc)
+{
+}
+#endif
+
+
+/* With per-bucket locks this operation is not-atomic, so that
+ * this version is not worse.
+ */
+static inline int __sk_prot_rehash(struct sock *sk)
+{
+ sk->sk_prot->unhash(sk);
+ return sk->sk_prot->hash(sk);
+}
+
+/* About 10 seconds */
+#define SOCK_DESTROY_TIME (10*HZ)
+
+/* Sockets 0-1023 can't be bound to unless you are superuser */
+#define PROT_SOCK 1024
+
+#define SHUTDOWN_MASK 3
+#define RCV_SHUTDOWN 1
+#define SEND_SHUTDOWN 2
+
+#define SOCK_SNDBUF_LOCK 1
+#define SOCK_RCVBUF_LOCK 2
+#define SOCK_BINDADDR_LOCK 4
+#define SOCK_BINDPORT_LOCK 8
+
+struct socket_alloc {
+ struct socket socket;
+ struct inode vfs_inode;
+};
+
+static inline struct socket *SOCKET_I(struct inode *inode)
+{
+ return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
+}
+
+static inline struct inode *SOCK_INODE(struct socket *socket)
+{
+ return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
+}
+
+/*
+ * Functions for memory accounting
+ */
+int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind);
+int __sk_mem_schedule(struct sock *sk, int size, int kind);
+void __sk_mem_reduce_allocated(struct sock *sk, int amount);
+void __sk_mem_reclaim(struct sock *sk, int amount);
+
+/* We used to have PAGE_SIZE here, but systems with 64KB pages
+ * do not necessarily have 16x time more memory than 4KB ones.
+ */
+#define SK_MEM_QUANTUM 4096
+#define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM)
+#define SK_MEM_SEND 0
+#define SK_MEM_RECV 1
+
+/* sysctl_mem values are in pages, we convert them in SK_MEM_QUANTUM units */
+static inline long sk_prot_mem_limits(const struct sock *sk, int index)
+{
+ long val = sk->sk_prot->sysctl_mem[index];
+
+#if PAGE_SIZE > SK_MEM_QUANTUM
+ val <<= PAGE_SHIFT - SK_MEM_QUANTUM_SHIFT;
+#elif PAGE_SIZE < SK_MEM_QUANTUM
+ val >>= SK_MEM_QUANTUM_SHIFT - PAGE_SHIFT;
+#endif
+ return val;
+}
+
+static inline int sk_mem_pages(int amt)
+{
+ return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT;
+}
+
+static inline bool sk_has_account(struct sock *sk)
+{
+ /* return true if protocol supports memory accounting */
+ return !!sk->sk_prot->memory_allocated;
+}
+
+static inline bool sk_wmem_schedule(struct sock *sk, int size)
+{
+ if (!sk_has_account(sk))
+ return true;
+ return size <= sk->sk_forward_alloc ||
+ __sk_mem_schedule(sk, size, SK_MEM_SEND);
+}
+
+static inline bool
+sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size)
+{
+ if (!sk_has_account(sk))
+ return true;
+ return size<= sk->sk_forward_alloc ||
+ __sk_mem_schedule(sk, size, SK_MEM_RECV) ||
+ skb_pfmemalloc(skb);
+}
+
+static inline void sk_mem_reclaim(struct sock *sk)
+{
+ if (!sk_has_account(sk))
+ return;
+ if (sk->sk_forward_alloc >= SK_MEM_QUANTUM)
+ __sk_mem_reclaim(sk, sk->sk_forward_alloc);
+}
+
+static inline void sk_mem_reclaim_partial(struct sock *sk)
+{
+ if (!sk_has_account(sk))
+ return;
+ if (sk->sk_forward_alloc > SK_MEM_QUANTUM)
+ __sk_mem_reclaim(sk, sk->sk_forward_alloc - 1);
+}
+
+static inline void sk_mem_charge(struct sock *sk, int size)
+{
+ if (!sk_has_account(sk))
+ return;
+ sk->sk_forward_alloc -= size;
+}
+
+static inline void sk_mem_uncharge(struct sock *sk, int size)
+{
+ if (!sk_has_account(sk))
+ return;
+ sk->sk_forward_alloc += size;
+
+ /* Avoid a possible overflow.
+ * TCP send queues can make this happen, if sk_mem_reclaim()
+ * is not called and more than 2 GBytes are released at once.
+ *
+ * If we reach 2 MBytes, reclaim 1 MBytes right now, there is
+ * no need to hold that much forward allocation anyway.
+ */
+ if (unlikely(sk->sk_forward_alloc >= 1 << 21))
+ __sk_mem_reclaim(sk, 1 << 20);
+}
+
+static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb)
+{
+ sock_set_flag(sk, SOCK_QUEUE_SHRUNK);
+ sk->sk_wmem_queued -= skb->truesize;
+ sk_mem_uncharge(sk, skb->truesize);
+ __kfree_skb(skb);
+}
+
+static inline void sock_release_ownership(struct sock *sk)
+{
+ if (sk->sk_lock.owned) {
+ sk->sk_lock.owned = 0;
+
+ /* The sk_lock has mutex_unlock() semantics: */
+ mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
+ }
+}
+
+/*
+ * Macro so as to not evaluate some arguments when
+ * lockdep is not enabled.
+ *
+ * Mark both the sk_lock and the sk_lock.slock as a
+ * per-address-family lock class.
+ */
+#define sock_lock_init_class_and_name(sk, sname, skey, name, key) \
+do { \
+ sk->sk_lock.owned = 0; \
+ init_waitqueue_head(&sk->sk_lock.wq); \
+ spin_lock_init(&(sk)->sk_lock.slock); \
+ debug_check_no_locks_freed((void *)&(sk)->sk_lock, \
+ sizeof((sk)->sk_lock)); \
+ lockdep_set_class_and_name(&(sk)->sk_lock.slock, \
+ (skey), (sname)); \
+ lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \
+} while (0)
+
+#ifdef CONFIG_LOCKDEP
+static inline bool lockdep_sock_is_held(const struct sock *sk)
+{
+ return lockdep_is_held(&sk->sk_lock) ||
+ lockdep_is_held(&sk->sk_lock.slock);
+}
+#endif
+
+void lock_sock_nested(struct sock *sk, int subclass);
+
+static inline void lock_sock(struct sock *sk)
+{
+ lock_sock_nested(sk, 0);
+}
+
+void __release_sock(struct sock *sk);
+void release_sock(struct sock *sk);
+
+/* BH context may only use the following locking interface. */
+#define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock))
+#define bh_lock_sock_nested(__sk) \
+ spin_lock_nested(&((__sk)->sk_lock.slock), \
+ SINGLE_DEPTH_NESTING)
+#define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock))
+
+bool lock_sock_fast(struct sock *sk);
+/**
+ * unlock_sock_fast - complement of lock_sock_fast
+ * @sk: socket
+ * @slow: slow mode
+ *
+ * fast unlock socket for user context.
+ * If slow mode is on, we call regular release_sock()
+ */
+static inline void unlock_sock_fast(struct sock *sk, bool slow)
+{
+ if (slow)
+ release_sock(sk);
+ else
+ spin_unlock_bh(&sk->sk_lock.slock);
+}
+
+/* Used by processes to "lock" a socket state, so that
+ * interrupts and bottom half handlers won't change it
+ * from under us. It essentially blocks any incoming
+ * packets, so that we won't get any new data or any
+ * packets that change the state of the socket.
+ *
+ * While locked, BH processing will add new packets to
+ * the backlog queue. This queue is processed by the
+ * owner of the socket lock right before it is released.
+ *
+ * Since ~2.3.5 it is also exclusive sleep lock serializing
+ * accesses from user process context.
+ */
+
+static inline void sock_owned_by_me(const struct sock *sk)
+{
+#ifdef CONFIG_LOCKDEP
+ WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks);
+#endif
+}
+
+static inline bool sock_owned_by_user(const struct sock *sk)
+{
+ sock_owned_by_me(sk);
+ return sk->sk_lock.owned;
+}
+
+static inline bool sock_owned_by_user_nocheck(const struct sock *sk)
+{
+ return sk->sk_lock.owned;
+}
+
+/* no reclassification while locks are held */
+static inline bool sock_allow_reclassification(const struct sock *csk)
+{
+ struct sock *sk = (struct sock *)csk;
+
+ return !sk->sk_lock.owned && !spin_is_locked(&sk->sk_lock.slock);
+}
+
+struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
+ struct proto *prot, int kern);
+void sk_free(struct sock *sk);
+void sk_destruct(struct sock *sk);
+struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority);
+void sk_free_unlock_clone(struct sock *sk);
+
+struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
+ gfp_t priority);
+void __sock_wfree(struct sk_buff *skb);
+void sock_wfree(struct sk_buff *skb);
+struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
+ gfp_t priority);
+void skb_orphan_partial(struct sk_buff *skb);
+void sock_rfree(struct sk_buff *skb);
+void sock_efree(struct sk_buff *skb);
+#ifdef CONFIG_INET
+void sock_edemux(struct sk_buff *skb);
+#else
+#define sock_edemux sock_efree
+#endif
+
+int sock_setsockopt(struct socket *sock, int level, int op,
+ char __user *optval, unsigned int optlen);
+
+int sock_getsockopt(struct socket *sock, int level, int op,
+ char __user *optval, int __user *optlen);
+struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
+ int noblock, int *errcode);
+struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
+ unsigned long data_len, int noblock,
+ int *errcode, int max_page_order);
+void *sock_kmalloc(struct sock *sk, int size, gfp_t priority);
+void sock_kfree_s(struct sock *sk, void *mem, int size);
+void sock_kzfree_s(struct sock *sk, void *mem, int size);
+void sk_send_sigurg(struct sock *sk);
+
+struct sockcm_cookie {
+ u64 transmit_time;
+ u32 mark;
+ u16 tsflags;
+};
+
+static inline void sockcm_init(struct sockcm_cookie *sockc,
+ const struct sock *sk)
+{
+ *sockc = (struct sockcm_cookie) { .tsflags = sk->sk_tsflags };
+}
+
+int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg,
+ struct sockcm_cookie *sockc);
+int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
+ struct sockcm_cookie *sockc);
+
+/*
+ * Functions to fill in entries in struct proto_ops when a protocol
+ * does not implement a particular function.
+ */
+int sock_no_bind(struct socket *, struct sockaddr *, int);
+int sock_no_connect(struct socket *, struct sockaddr *, int, int);
+int sock_no_socketpair(struct socket *, struct socket *);
+int sock_no_accept(struct socket *, struct socket *, int, bool);
+int sock_no_getname(struct socket *, struct sockaddr *, int);
+int sock_no_ioctl(struct socket *, unsigned int, unsigned long);
+int sock_no_listen(struct socket *, int);
+int sock_no_shutdown(struct socket *, int);
+int sock_no_getsockopt(struct socket *, int , int, char __user *, int __user *);
+int sock_no_setsockopt(struct socket *, int, int, char __user *, unsigned int);
+int sock_no_sendmsg(struct socket *, struct msghdr *, size_t);
+int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len);
+int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int);
+int sock_no_mmap(struct file *file, struct socket *sock,
+ struct vm_area_struct *vma);
+ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset,
+ size_t size, int flags);
+ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
+ int offset, size_t size, int flags);
+
+/*
+ * Functions to fill in entries in struct proto_ops when a protocol
+ * uses the inet style.
+ */
+int sock_common_getsockopt(struct socket *sock, int level, int optname,
+ char __user *optval, int __user *optlen);
+int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
+ int flags);
+int sock_common_setsockopt(struct socket *sock, int level, int optname,
+ char __user *optval, unsigned int optlen);
+int compat_sock_common_getsockopt(struct socket *sock, int level,
+ int optname, char __user *optval, int __user *optlen);
+int compat_sock_common_setsockopt(struct socket *sock, int level,
+ int optname, char __user *optval, unsigned int optlen);
+
+void sk_common_release(struct sock *sk);
+
+/*
+ * Default socket callbacks and setup code
+ */
+
+/* Initialise core socket variables */
+void sock_init_data(struct socket *sock, struct sock *sk);
+
+/*
+ * Socket reference counting postulates.
+ *
+ * * Each user of socket SHOULD hold a reference count.
+ * * Each access point to socket (an hash table bucket, reference from a list,
+ * running timer, skb in flight MUST hold a reference count.
+ * * When reference count hits 0, it means it will never increase back.
+ * * When reference count hits 0, it means that no references from
+ * outside exist to this socket and current process on current CPU
+ * is last user and may/should destroy this socket.
+ * * sk_free is called from any context: process, BH, IRQ. When
+ * it is called, socket has no references from outside -> sk_free
+ * may release descendant resources allocated by the socket, but
+ * to the time when it is called, socket is NOT referenced by any
+ * hash tables, lists etc.
+ * * Packets, delivered from outside (from network or from another process)
+ * and enqueued on receive/error queues SHOULD NOT grab reference count,
+ * when they sit in queue. Otherwise, packets will leak to hole, when
+ * socket is looked up by one cpu and unhasing is made by another CPU.
+ * It is true for udp/raw, netlink (leak to receive and error queues), tcp
+ * (leak to backlog). Packet socket does all the processing inside
+ * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
+ * use separate SMP lock, so that they are prone too.
+ */
+
+/* Ungrab socket and destroy it, if it was the last reference. */
+static inline void sock_put(struct sock *sk)
+{
+ if (refcount_dec_and_test(&sk->sk_refcnt))
+ sk_free(sk);
+}
+/* Generic version of sock_put(), dealing with all sockets
+ * (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...)
+ */
+void sock_gen_put(struct sock *sk);
+
+int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested,
+ unsigned int trim_cap, bool refcounted);
+static inline int sk_receive_skb(struct sock *sk, struct sk_buff *skb,
+ const int nested)
+{
+ return __sk_receive_skb(sk, skb, nested, 1, true);
+}
+
+static inline void sk_tx_queue_set(struct sock *sk, int tx_queue)
+{
+ /* sk_tx_queue_mapping accept only upto a 16-bit value */
+ if (WARN_ON_ONCE((unsigned short)tx_queue >= USHRT_MAX))
+ return;
+ sk->sk_tx_queue_mapping = tx_queue;
+}
+
+#define NO_QUEUE_MAPPING USHRT_MAX
+
+static inline void sk_tx_queue_clear(struct sock *sk)
+{
+ sk->sk_tx_queue_mapping = NO_QUEUE_MAPPING;
+}
+
+static inline int sk_tx_queue_get(const struct sock *sk)
+{
+ if (sk && sk->sk_tx_queue_mapping != NO_QUEUE_MAPPING)
+ return sk->sk_tx_queue_mapping;
+
+ return -1;
+}
+
+static inline void sk_rx_queue_set(struct sock *sk, const struct sk_buff *skb)
+{
+#ifdef CONFIG_XPS
+ if (skb_rx_queue_recorded(skb)) {
+ u16 rx_queue = skb_get_rx_queue(skb);
+
+ if (WARN_ON_ONCE(rx_queue == NO_QUEUE_MAPPING))
+ return;
+
+ sk->sk_rx_queue_mapping = rx_queue;
+ }
+#endif
+}
+
+static inline void sk_rx_queue_clear(struct sock *sk)
+{
+#ifdef CONFIG_XPS
+ sk->sk_rx_queue_mapping = NO_QUEUE_MAPPING;
+#endif
+}
+
+#ifdef CONFIG_XPS
+static inline int sk_rx_queue_get(const struct sock *sk)
+{
+ if (sk && sk->sk_rx_queue_mapping != NO_QUEUE_MAPPING)
+ return sk->sk_rx_queue_mapping;
+
+ return -1;
+}
+#endif
+
+static inline void sk_set_socket(struct sock *sk, struct socket *sock)
+{
+ sk_tx_queue_clear(sk);
+ sk->sk_socket = sock;
+}
+
+static inline wait_queue_head_t *sk_sleep(struct sock *sk)
+{
+ BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0);
+ return &rcu_dereference_raw(sk->sk_wq)->wait;
+}
+/* Detach socket from process context.
+ * Announce socket dead, detach it from wait queue and inode.
+ * Note that parent inode held reference count on this struct sock,
+ * we do not release it in this function, because protocol
+ * probably wants some additional cleanups or even continuing
+ * to work with this socket (TCP).
+ */
+static inline void sock_orphan(struct sock *sk)
+{
+ write_lock_bh(&sk->sk_callback_lock);
+ sock_set_flag(sk, SOCK_DEAD);
+ sk_set_socket(sk, NULL);
+ sk->sk_wq = NULL;
+ write_unlock_bh(&sk->sk_callback_lock);
+}
+
+static inline void sock_graft(struct sock *sk, struct socket *parent)
+{
+ WARN_ON(parent->sk);
+ write_lock_bh(&sk->sk_callback_lock);
+ rcu_assign_pointer(sk->sk_wq, parent->wq);
+ parent->sk = sk;
+ sk_set_socket(sk, parent);
+ sk->sk_uid = SOCK_INODE(parent)->i_uid;
+ security_sock_graft(sk, parent);
+ write_unlock_bh(&sk->sk_callback_lock);
+}
+
+kuid_t sock_i_uid(struct sock *sk);
+unsigned long sock_i_ino(struct sock *sk);
+
+static inline kuid_t sock_net_uid(const struct net *net, const struct sock *sk)
+{
+ return sk ? sk->sk_uid : make_kuid(net->user_ns, 0);
+}
+
+static inline u32 net_tx_rndhash(void)
+{
+ u32 v = prandom_u32();
+
+ return v ?: 1;
+}
+
+static inline void sk_set_txhash(struct sock *sk)
+{
+ sk->sk_txhash = net_tx_rndhash();
+}
+
+static inline void sk_rethink_txhash(struct sock *sk)
+{
+ if (sk->sk_txhash)
+ sk_set_txhash(sk);
+}
+
+static inline struct dst_entry *
+__sk_dst_get(struct sock *sk)
+{
+ return rcu_dereference_check(sk->sk_dst_cache,
+ lockdep_sock_is_held(sk));
+}
+
+static inline struct dst_entry *
+sk_dst_get(struct sock *sk)
+{
+ struct dst_entry *dst;
+
+ rcu_read_lock();
+ dst = rcu_dereference(sk->sk_dst_cache);
+ if (dst && !atomic_inc_not_zero(&dst->__refcnt))
+ dst = NULL;
+ rcu_read_unlock();
+ return dst;
+}
+
+static inline void dst_negative_advice(struct sock *sk)
+{
+ struct dst_entry *ndst, *dst = __sk_dst_get(sk);
+
+ sk_rethink_txhash(sk);
+
+ if (dst && dst->ops->negative_advice) {
+ ndst = dst->ops->negative_advice(dst);
+
+ if (ndst != dst) {
+ rcu_assign_pointer(sk->sk_dst_cache, ndst);
+ sk_tx_queue_clear(sk);
+ sk->sk_dst_pending_confirm = 0;
+ }
+ }
+}
+
+static inline void
+__sk_dst_set(struct sock *sk, struct dst_entry *dst)
+{
+ struct dst_entry *old_dst;
+
+ sk_tx_queue_clear(sk);
+ sk->sk_dst_pending_confirm = 0;
+ old_dst = rcu_dereference_protected(sk->sk_dst_cache,
+ lockdep_sock_is_held(sk));
+ rcu_assign_pointer(sk->sk_dst_cache, dst);
+ dst_release(old_dst);
+}
+
+static inline void
+sk_dst_set(struct sock *sk, struct dst_entry *dst)
+{
+ struct dst_entry *old_dst;
+
+ sk_tx_queue_clear(sk);
+ sk->sk_dst_pending_confirm = 0;
+ old_dst = xchg((__force struct dst_entry **)&sk->sk_dst_cache, dst);
+ dst_release(old_dst);
+}
+
+static inline void
+__sk_dst_reset(struct sock *sk)
+{
+ __sk_dst_set(sk, NULL);
+}
+
+static inline void
+sk_dst_reset(struct sock *sk)
+{
+ sk_dst_set(sk, NULL);
+}
+
+struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
+
+struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
+
+static inline void sk_dst_confirm(struct sock *sk)
+{
+ if (!sk->sk_dst_pending_confirm)
+ sk->sk_dst_pending_confirm = 1;
+}
+
+static inline void sock_confirm_neigh(struct sk_buff *skb, struct neighbour *n)
+{
+ if (skb_get_dst_pending_confirm(skb)) {
+ struct sock *sk = skb->sk;
+ unsigned long now = jiffies;
+
+ /* avoid dirtying neighbour */
+ if (n->confirmed != now)
+ n->confirmed = now;
+ if (sk && sk->sk_dst_pending_confirm)
+ sk->sk_dst_pending_confirm = 0;
+ }
+}
+
+bool sk_mc_loop(struct sock *sk);
+
+static inline bool sk_can_gso(const struct sock *sk)
+{
+ return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type);
+}
+
+void sk_setup_caps(struct sock *sk, struct dst_entry *dst);
+
+static inline void sk_nocaps_add(struct sock *sk, netdev_features_t flags)
+{
+ sk->sk_route_nocaps |= flags;
+ sk->sk_route_caps &= ~flags;
+}
+
+static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
+ struct iov_iter *from, char *to,
+ int copy, int offset)
+{
+ if (skb->ip_summed == CHECKSUM_NONE) {
+ __wsum csum = 0;
+ if (!csum_and_copy_from_iter_full(to, copy, &csum, from))
+ return -EFAULT;
+ skb->csum = csum_block_add(skb->csum, csum, offset);
+ } else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
+ if (!copy_from_iter_full_nocache(to, copy, from))
+ return -EFAULT;
+ } else if (!copy_from_iter_full(to, copy, from))
+ return -EFAULT;
+
+ return 0;
+}
+
+static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
+ struct iov_iter *from, int copy)
+{
+ int err, offset = skb->len;
+
+ err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy),
+ copy, offset);
+ if (err)
+ __skb_trim(skb, offset);
+
+ return err;
+}
+
+static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from,
+ struct sk_buff *skb,
+ struct page *page,
+ int off, int copy)
+{
+ int err;
+
+ err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off,
+ copy, skb->len);
+ if (err)
+ return err;
+
+ skb->len += copy;
+ skb->data_len += copy;
+ skb->truesize += copy;
+ sk->sk_wmem_queued += copy;
+ sk_mem_charge(sk, copy);
+ return 0;
+}
+
+/**
+ * sk_wmem_alloc_get - returns write allocations
+ * @sk: socket
+ *
+ * Returns sk_wmem_alloc minus initial offset of one
+ */
+static inline int sk_wmem_alloc_get(const struct sock *sk)
+{
+ return refcount_read(&sk->sk_wmem_alloc) - 1;
+}
+
+/**
+ * sk_rmem_alloc_get - returns read allocations
+ * @sk: socket
+ *
+ * Returns sk_rmem_alloc
+ */
+static inline int sk_rmem_alloc_get(const struct sock *sk)
+{
+ return atomic_read(&sk->sk_rmem_alloc);
+}
+
+/**
+ * sk_has_allocations - check if allocations are outstanding
+ * @sk: socket
+ *
+ * Returns true if socket has write or read allocations
+ */
+static inline bool sk_has_allocations(const struct sock *sk)
+{
+ return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk);
+}
+
+/**
+ * skwq_has_sleeper - check if there are any waiting processes
+ * @wq: struct socket_wq
+ *
+ * Returns true if socket_wq has waiting processes
+ *
+ * The purpose of the skwq_has_sleeper and sock_poll_wait is to wrap the memory
+ * barrier call. They were added due to the race found within the tcp code.
+ *
+ * Consider following tcp code paths::
+ *
+ * CPU1 CPU2
+ * sys_select receive packet
+ * ... ...
+ * __add_wait_queue update tp->rcv_nxt
+ * ... ...
+ * tp->rcv_nxt check sock_def_readable
+ * ... {
+ * schedule rcu_read_lock();
+ * wq = rcu_dereference(sk->sk_wq);
+ * if (wq && waitqueue_active(&wq->wait))
+ * wake_up_interruptible(&wq->wait)
+ * ...
+ * }
+ *
+ * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
+ * in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1
+ * could then endup calling schedule and sleep forever if there are no more
+ * data on the socket.
+ *
+ */
+static inline bool skwq_has_sleeper(struct socket_wq *wq)
+{
+ return wq && wq_has_sleeper(&wq->wait);
+}
+
+/**
+ * sock_poll_wait - place memory barrier behind the poll_wait call.
+ * @filp: file
+ * @sock: socket to wait on
+ * @p: poll_table
+ *
+ * See the comments in the wq_has_sleeper function.
+ *
+ * Do not derive sock from filp->private_data here. An SMC socket establishes
+ * an internal TCP socket that is used in the fallback case. All socket
+ * operations on the SMC socket are then forwarded to the TCP socket. In case of
+ * poll, the filp->private_data pointer references the SMC socket because the
+ * TCP socket has no file assigned.
+ */
+static inline void sock_poll_wait(struct file *filp, struct socket *sock,
+ poll_table *p)
+{
+ if (!poll_does_not_wait(p)) {
+ poll_wait(filp, &sock->wq->wait, p);
+ /* We need to be sure we are in sync with the
+ * socket flags modification.
+ *
+ * This memory barrier is paired in the wq_has_sleeper.
+ */
+ smp_mb();
+ }
+}
+
+static inline void skb_set_hash_from_sk(struct sk_buff *skb, struct sock *sk)
+{
+ if (sk->sk_txhash) {
+ skb->l4_hash = 1;
+ skb->hash = sk->sk_txhash;
+ }
+}
+
+void skb_set_owner_w(struct sk_buff *skb, struct sock *sk);
+
+/*
+ * Queue a received datagram if it will fit. Stream and sequenced
+ * protocols can't normally use this as they need to fit buffers in
+ * and play with them.
+ *
+ * Inlined as it's very short and called for pretty much every
+ * packet ever received.
+ */
+static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
+{
+ skb_orphan(skb);
+ skb->sk = sk;
+ skb->destructor = sock_rfree;
+ atomic_add(skb->truesize, &sk->sk_rmem_alloc);
+ sk_mem_charge(sk, skb->truesize);
+}
+
+void sk_reset_timer(struct sock *sk, struct timer_list *timer,
+ unsigned long expires);
+
+void sk_stop_timer(struct sock *sk, struct timer_list *timer);
+
+int __sk_queue_drop_skb(struct sock *sk, struct sk_buff_head *sk_queue,
+ struct sk_buff *skb, unsigned int flags,
+ void (*destructor)(struct sock *sk,
+ struct sk_buff *skb));
+int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
+int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
+
+int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
+struct sk_buff *sock_dequeue_err_skb(struct sock *sk);
+
+/*
+ * Recover an error report and clear atomically
+ */
+
+static inline int sock_error(struct sock *sk)
+{
+ int err;
+ if (likely(!sk->sk_err))
+ return 0;
+ err = xchg(&sk->sk_err, 0);
+ return -err;
+}
+
+static inline unsigned long sock_wspace(struct sock *sk)
+{
+ int amt = 0;
+
+ if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
+ amt = sk->sk_sndbuf - refcount_read(&sk->sk_wmem_alloc);
+ if (amt < 0)
+ amt = 0;
+ }
+ return amt;
+}
+
+/* Note:
+ * We use sk->sk_wq_raw, from contexts knowing this
+ * pointer is not NULL and cannot disappear/change.
+ */
+static inline void sk_set_bit(int nr, struct sock *sk)
+{
+ if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
+ !sock_flag(sk, SOCK_FASYNC))
+ return;
+
+ set_bit(nr, &sk->sk_wq_raw->flags);
+}
+
+static inline void sk_clear_bit(int nr, struct sock *sk)
+{
+ if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
+ !sock_flag(sk, SOCK_FASYNC))
+ return;
+
+ clear_bit(nr, &sk->sk_wq_raw->flags);
+}
+
+static inline void sk_wake_async(const struct sock *sk, int how, int band)
+{
+ if (sock_flag(sk, SOCK_FASYNC)) {
+ rcu_read_lock();
+ sock_wake_async(rcu_dereference(sk->sk_wq), how, band);
+ rcu_read_unlock();
+ }
+}
+
+/* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might
+ * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak.
+ * Note: for send buffers, TCP works better if we can build two skbs at
+ * minimum.
+ */
+#define TCP_SKB_MIN_TRUESIZE (2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff)))
+
+#define SOCK_MIN_SNDBUF (TCP_SKB_MIN_TRUESIZE * 2)
+#define SOCK_MIN_RCVBUF TCP_SKB_MIN_TRUESIZE
+
+static inline void sk_stream_moderate_sndbuf(struct sock *sk)
+{
+ if (!(sk->sk_userlocks & SOCK_SNDBUF_LOCK)) {
+ sk->sk_sndbuf = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
+ sk->sk_sndbuf = max_t(u32, sk->sk_sndbuf, SOCK_MIN_SNDBUF);
+ }
+}
+
+struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp,
+ bool force_schedule);
+
+/**
+ * sk_page_frag - return an appropriate page_frag
+ * @sk: socket
+ *
+ * If socket allocation mode allows current thread to sleep, it means its
+ * safe to use the per task page_frag instead of the per socket one.
+ */
+static inline struct page_frag *sk_page_frag(struct sock *sk)
+{
+ if (gfpflags_allow_blocking(sk->sk_allocation))
+ return ¤t->task_frag;
+
+ return &sk->sk_frag;
+}
+
+bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag);
+
+int sk_alloc_sg(struct sock *sk, int len, struct scatterlist *sg,
+ int sg_start, int *sg_curr, unsigned int *sg_size,
+ int first_coalesce);
+
+/*
+ * Default write policy as shown to user space via poll/select/SIGIO
+ */
+static inline bool sock_writeable(const struct sock *sk)
+{
+ return refcount_read(&sk->sk_wmem_alloc) < (sk->sk_sndbuf >> 1);
+}
+
+static inline gfp_t gfp_any(void)
+{
+ return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
+}
+
+static inline long sock_rcvtimeo(const struct sock *sk, bool noblock)
+{
+ return noblock ? 0 : sk->sk_rcvtimeo;
+}
+
+static inline long sock_sndtimeo(const struct sock *sk, bool noblock)
+{
+ return noblock ? 0 : sk->sk_sndtimeo;
+}
+
+static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
+{
+ return (waitall ? len : min_t(int, sk->sk_rcvlowat, len)) ? : 1;
+}
+
+/* Alas, with timeout socket operations are not restartable.
+ * Compare this to poll().
+ */
+static inline int sock_intr_errno(long timeo)
+{
+ return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
+}
+
+struct sock_skb_cb {
+ u32 dropcount;
+};
+
+/* Store sock_skb_cb at the end of skb->cb[] so protocol families
+ * using skb->cb[] would keep using it directly and utilize its
+ * alignement guarantee.
+ */
+#define SOCK_SKB_CB_OFFSET ((FIELD_SIZEOF(struct sk_buff, cb) - \
+ sizeof(struct sock_skb_cb)))
+
+#define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \
+ SOCK_SKB_CB_OFFSET))
+
+#define sock_skb_cb_check_size(size) \
+ BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET)
+
+static inline void
+sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb)
+{
+ SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, SOCK_RXQ_OVFL) ?
+ atomic_read(&sk->sk_drops) : 0;
+}
+
+static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb)
+{
+ int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs);
+
+ atomic_add(segs, &sk->sk_drops);
+}
+
+void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
+ struct sk_buff *skb);
+void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
+ struct sk_buff *skb);
+
+static inline void
+sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
+{
+ ktime_t kt = skb->tstamp;
+ struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
+
+ /*
+ * generate control messages if
+ * - receive time stamping in software requested
+ * - software time stamp available and wanted
+ * - hardware time stamps available and wanted
+ */
+ if (sock_flag(sk, SOCK_RCVTSTAMP) ||
+ (sk->sk_tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) ||
+ (kt && sk->sk_tsflags & SOF_TIMESTAMPING_SOFTWARE) ||
+ (hwtstamps->hwtstamp &&
+ (sk->sk_tsflags & SOF_TIMESTAMPING_RAW_HARDWARE)))
+ __sock_recv_timestamp(msg, sk, skb);
+ else
+ sk->sk_stamp = kt;
+
+ if (sock_flag(sk, SOCK_WIFI_STATUS) && skb->wifi_acked_valid)
+ __sock_recv_wifi_status(msg, sk, skb);
+}
+
+void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
+ struct sk_buff *skb);
+
+#define SK_DEFAULT_STAMP (-1L * NSEC_PER_SEC)
+static inline void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
+ struct sk_buff *skb)
+{
+#define FLAGS_TS_OR_DROPS ((1UL << SOCK_RXQ_OVFL) | \
+ (1UL << SOCK_RCVTSTAMP))
+#define TSFLAGS_ANY (SOF_TIMESTAMPING_SOFTWARE | \
+ SOF_TIMESTAMPING_RAW_HARDWARE)
+
+ if (sk->sk_flags & FLAGS_TS_OR_DROPS || sk->sk_tsflags & TSFLAGS_ANY)
+ __sock_recv_ts_and_drops(msg, sk, skb);
+ else if (unlikely(sock_flag(sk, SOCK_TIMESTAMP)))
+ sk->sk_stamp = skb->tstamp;
+ else if (unlikely(sk->sk_stamp == SK_DEFAULT_STAMP))
+ sk->sk_stamp = 0;
+}
+
+void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags);
+
+/**
+ * sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
+ * @sk: socket sending this packet
+ * @tsflags: timestamping flags to use
+ * @tx_flags: completed with instructions for time stamping
+ *
+ * Note: callers should take care of initial ``*tx_flags`` value (usually 0)
+ */
+static inline void sock_tx_timestamp(const struct sock *sk, __u16 tsflags,
+ __u8 *tx_flags)
+{
+ if (unlikely(tsflags))
+ __sock_tx_timestamp(tsflags, tx_flags);
+ if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS)))
+ *tx_flags |= SKBTX_WIFI_STATUS;
+}
+
+/**
+ * sk_eat_skb - Release a skb if it is no longer needed
+ * @sk: socket to eat this skb from
+ * @skb: socket buffer to eat
+ *
+ * This routine must be called with interrupts disabled or with the socket
+ * locked so that the sk_buff queue operation is ok.
+*/
+static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb)
+{
+ __skb_unlink(skb, &sk->sk_receive_queue);
+ __kfree_skb(skb);
+}
+
+static inline
+struct net *sock_net(const struct sock *sk)
+{
+ return read_pnet(&sk->sk_net);
+}
+
+static inline
+void sock_net_set(struct sock *sk, struct net *net)
+{
+ write_pnet(&sk->sk_net, net);
+}
+
+static inline struct sock *skb_steal_sock(struct sk_buff *skb)
+{
+ if (skb->sk) {
+ struct sock *sk = skb->sk;
+
+ skb->destructor = NULL;
+ skb->sk = NULL;
+ return sk;
+ }
+ return NULL;
+}
+
+/* This helper checks if a socket is a full socket,
+ * ie _not_ a timewait or request socket.
+ */
+static inline bool sk_fullsock(const struct sock *sk)
+{
+ return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV);
+}
+
+/* Checks if this SKB belongs to an HW offloaded socket
+ * and whether any SW fallbacks are required based on dev.
+ */
+static inline struct sk_buff *sk_validate_xmit_skb(struct sk_buff *skb,
+ struct net_device *dev)
+{
+#ifdef CONFIG_SOCK_VALIDATE_XMIT
+ struct sock *sk = skb->sk;
+
+ if (sk && sk_fullsock(sk) && sk->sk_validate_xmit_skb)
+ skb = sk->sk_validate_xmit_skb(sk, dev, skb);
+#endif
+
+ return skb;
+}
+
+/* This helper checks if a socket is a LISTEN or NEW_SYN_RECV
+ * SYNACK messages can be attached to either ones (depending on SYNCOOKIE)
+ */
+static inline bool sk_listener(const struct sock *sk)
+{
+ return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV);
+}
+
+void sock_enable_timestamp(struct sock *sk, int flag);
+int sock_get_timestamp(struct sock *, struct timeval __user *);
+int sock_get_timestampns(struct sock *, struct timespec __user *);
+int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level,
+ int type);
+
+bool sk_ns_capable(const struct sock *sk,
+ struct user_namespace *user_ns, int cap);
+bool sk_capable(const struct sock *sk, int cap);
+bool sk_net_capable(const struct sock *sk, int cap);
+
+void sk_get_meminfo(const struct sock *sk, u32 *meminfo);
+
+/* Take into consideration the size of the struct sk_buff overhead in the
+ * determination of these values, since that is non-constant across
+ * platforms. This makes socket queueing behavior and performance
+ * not depend upon such differences.
+ */
+#define _SK_MEM_PACKETS 256
+#define _SK_MEM_OVERHEAD SKB_TRUESIZE(256)
+#define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
+#define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
+
+extern __u32 sysctl_wmem_max;
+extern __u32 sysctl_rmem_max;
+
+extern int sysctl_tstamp_allow_data;
+extern int sysctl_optmem_max;
+
+extern __u32 sysctl_wmem_default;
+extern __u32 sysctl_rmem_default;
+
+static inline int sk_get_wmem0(const struct sock *sk, const struct proto *proto)
+{
+ /* Does this proto have per netns sysctl_wmem ? */
+ if (proto->sysctl_wmem_offset)
+ return *(int *)((void *)sock_net(sk) + proto->sysctl_wmem_offset);
+
+ return *proto->sysctl_wmem;
+}
+
+static inline int sk_get_rmem0(const struct sock *sk, const struct proto *proto)
+{
+ /* Does this proto have per netns sysctl_rmem ? */
+ if (proto->sysctl_rmem_offset)
+ return *(int *)((void *)sock_net(sk) + proto->sysctl_rmem_offset);
+
+ return *proto->sysctl_rmem;
+}
+
+/* Default TCP Small queue budget is ~1 ms of data (1sec >> 10)
+ * Some wifi drivers need to tweak it to get more chunks.
+ * They can use this helper from their ndo_start_xmit()
+ */
+static inline void sk_pacing_shift_update(struct sock *sk, int val)
+{
+ if (!sk || !sk_fullsock(sk) || sk->sk_pacing_shift == val)
+ return;
+ sk->sk_pacing_shift = val;
+}
+
+/* if a socket is bound to a device, check that the given device
+ * index is either the same or that the socket is bound to an L3
+ * master device and the given device index is also enslaved to
+ * that L3 master
+ */
+static inline bool sk_dev_equal_l3scope(struct sock *sk, int dif)
+{
+ int mdif;
+
+ if (!sk->sk_bound_dev_if || sk->sk_bound_dev_if == dif)
+ return true;
+
+ mdif = l3mdev_master_ifindex_by_index(sock_net(sk), dif);
+ if (mdif && mdif == sk->sk_bound_dev_if)
+ return true;
+
+ return false;
+}
+
+#endif /* _SOCK_H */