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android-kvm / linux / c35a824c31834d947fb99b0c608c1b9f922b4ba0 / . / include / net / sock.h
blob: bdc4323ce53c957c30809b0773b2d558dce555b7 [file] [log] [blame]
/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* 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
*/
#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/sockptr.h>
#include <linux/indirect_call_wrapper.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/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_addrpair: 8-byte-aligned __u64 union of @skc_daddr & @skc_rcv_saddr
* @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_portpair: __u32 union of @skc_dport & @skc_num
* @skc_family: network address family
* @skc_state: Connection state
* @skc_reuse: %SO_REUSEADDR setting
* @skc_reuseport: %SO_REUSEPORT setting
* @skc_ipv6only: socket is IPV6 only
* @skc_net_refcnt: socket is using net ref counting
* @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_v6_daddr: IPV6 destination address
* @skc_v6_rcv_saddr: IPV6 source address
* @skc_cookie: socket's cookie value
* @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_listener: connection request listener socket (aka rsk_listener)
* [union with @skc_flags]
* @skc_tw_dr: (aka tw_dr) ptr to &struct inet_timewait_death_row
* [union with @skc_flags]
* @skc_incoming_cpu: record/match cpu processing incoming packets
* @skc_rcv_wnd: (aka rsk_rcv_wnd) TCP receive window size (possibly scaled)
* [union with @skc_incoming_cpu]
* @skc_tw_rcv_nxt: (aka tw_rcv_nxt) TCP window next expected seq number
* [union with @skc_incoming_cpu]
* @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 bpf_local_storage;
/**
* 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_rx_skb_cache: cache copy of recently accessed RX skb
* @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_route_forced_caps: static, forced route capabilities
* (set in tcp_init_sock())
* @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_prefer_busy_poll: prefer busypolling over softirq processing
* @sk_busy_poll_budget: napi processing budget when busypolling
* @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_stamp_seq: lock for accessing sk_stamp on 32 bit architectures only
* @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
* @tcp_rtx_queue: TCP re-transmit queue [union with @sk_send_head]
* @sk_tx_skb_cache: cache copy of recently accessed TX skb
* @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_validate_xmit_skb: ptr to an optional validate function
* @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
* @sk_reuseport_cb: reuseport group container
* @sk_bpf_storage: ptr to cache and control for bpf_sk_storage
* @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_report_errors: set report errors 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 *sk_rx_skb_cache;
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;
/* private: */
struct socket_wq *sk_wq_raw;
/* public: */
};
#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 *sk_tx_skb_cache;
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;
unsigned long sk_pacing_rate; /* bytes per second */
unsigned long 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.
*/
u8 sk_padding : 1,
sk_kern_sock : 1,
sk_no_check_tx : 1,
sk_no_check_rx : 1,
sk_userlocks : 4;
u8 sk_pacing_shift;
u16 sk_type;
u16 sk_protocol;
u16 sk_gso_max_segs;
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;
#ifdef CONFIG_NET_RX_BUSY_POLL
u8 sk_prefer_busy_poll;
u16 sk_busy_poll_budget;
#endif
struct pid *sk_peer_pid;
const struct cred *sk_peer_cred;
long sk_rcvtimeo;
ktime_t sk_stamp;
#if BITS_PER_LONG==32
seqlock_t sk_stamp_seq;
#endif
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;
#ifdef CONFIG_BPF_SYSCALL
struct bpf_local_storage __rcu *sk_bpf_storage;
#endif
struct rcu_head sk_rcu;
};
enum sk_pacing {
SK_PACING_NONE = 0,
SK_PACING_NEEDED = 1,
SK_PACING_FQ = 2,
};
/* Pointer stored in sk_user_data might not be suitable for copying
* when cloning the socket. For instance, it can point to a reference
* counted object. sk_user_data bottom bit is set if pointer must not
* be copied.
*/
#define SK_USER_DATA_NOCOPY 1UL
#define SK_USER_DATA_BPF 2UL /* Managed by BPF */
#define SK_USER_DATA_PTRMASK ~(SK_USER_DATA_NOCOPY | SK_USER_DATA_BPF)
/**
* sk_user_data_is_nocopy - Test if sk_user_data pointer must not be copied
* @sk: socket
*/
static inline bool sk_user_data_is_nocopy(const struct sock *sk)
{
return ((uintptr_t)sk->sk_user_data & SK_USER_DATA_NOCOPY);
}
#define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data)))
#define rcu_dereference_sk_user_data(sk) \
({ \
void *__tmp = rcu_dereference(__sk_user_data((sk))); \
(void *)((uintptr_t)__tmp & SK_USER_DATA_PTRMASK); \
})
#define rcu_assign_sk_user_data(sk, ptr) \
({ \
uintptr_t __tmp = (uintptr_t)(ptr); \
WARN_ON_ONCE(__tmp & ~SK_USER_DATA_PTRMASK); \
rcu_assign_pointer(__sk_user_data((sk)), __tmp); \
})
#define rcu_assign_sk_user_data_nocopy(sk, ptr) \
({ \
uintptr_t __tmp = (uintptr_t)(ptr); \
WARN_ON_ONCE(__tmp & ~SK_USER_DATA_PTRMASK); \
rcu_assign_pointer(__sk_user_data((sk)), \
__tmp | SK_USER_DATA_NOCOPY); \
})
/*
* 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_add_node_tail_rcu(struct sock *sk, struct hlist_head *list)
{
sock_hold(sk);
hlist_add_tail_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_tail_rcu(struct sock *sk, struct hlist_nulls_head *list)
{
hlist_nulls_add_tail_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_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,
SOCK_XDP, /* XDP is attached */
SOCK_TSTAMP_NEW, /* Indicates 64 bit timestamps always */
};
#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 void sock_valbool_flag(struct sock *sk, enum sock_flags bit,
int valbool)
{
if (valbool)
sock_set_flag(sk, bit);
else
sock_reset_flag(sk, bit);
}
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);
}
void __receive_sock(struct file *file);
#else
static inline int sk_memalloc_socks(void)
{
return 0;
}
static inline void __receive_sock(struct file *file)
{ }
#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)
{
WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog - 1);
}
static inline void sk_acceptq_added(struct sock *sk)
{
WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog + 1);
}
static inline bool sk_acceptq_is_full(const struct sock *sk)
{
return READ_ONCE(sk->sk_ack_backlog) > READ_ONCE(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 READ_ONCE(sk->sk_wmem_queued) >> 1;
}
static inline int sk_stream_wspace(const struct sock *sk)
{
return READ_ONCE(sk->sk_sndbuf) - READ_ONCE(sk->sk_wmem_queued);
}
static inline void sk_wmem_queued_add(struct sock *sk, int val)
{
WRITE_ONCE(sk->sk_wmem_queued, sk->sk_wmem_queued + val);
}
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)
WRITE_ONCE(sk->sk_backlog.head, skb);
else
sk->sk_backlog.tail->next = skb;
WRITE_ONCE(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(READ_ONCE(sk->sk_incoming_cpu) != cpu))
WRITE_ONCE(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_branch_unlikely(&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, sockptr_t 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_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 *addr, int addr_len);
int (*bind_add)(struct sock *sk,
struct sockaddr *addr, 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, int wake);
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 */
INDIRECT_CALLABLE_DECLARE(bool tcp_stream_memory_free(const struct sock *sk, int wake));
static inline bool __sk_stream_memory_free(const struct sock *sk, int wake)
{
if (READ_ONCE(sk->sk_wmem_queued) >= READ_ONCE(sk->sk_sndbuf))
return false;
#ifdef CONFIG_INET
return sk->sk_prot->stream_memory_free ?
INDIRECT_CALL_1(sk->sk_prot->stream_memory_free,
tcp_stream_memory_free,
sk, wake) : true;
#else
return sk->sk_prot->stream_memory_free ?
sk->sk_prot->stream_memory_free(sk, wake) : true;
#endif
}
static inline bool sk_stream_memory_free(const struct sock *sk)
{
return __sk_stream_memory_free(sk, 0);
}
static inline bool __sk_stream_is_writeable(const struct sock *sk, int wake)
{
return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) &&
__sk_stream_memory_free(sk, wake);
}
static inline bool sk_stream_is_writeable(const struct sock *sk)
{
return __sk_stream_is_writeable(sk, 0);
}
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 u64
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);
}
DECLARE_STATIC_KEY_FALSE(tcp_tx_skb_cache_key);
static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb)
{
sk_wmem_queued_add(sk, -skb->truesize);
sk_mem_uncharge(sk, skb->truesize);
if (static_branch_unlikely(&tcp_tx_skb_cache_key) &&
!sk->sk_tx_skb_cache && !skb_cloned(skb)) {
skb_ext_reset(skb);
skb_zcopy_clear(skb, true);
sk->sk_tx_skb_cache = skb;
return;
}
__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, _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)
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);
}
void lock_sock_nested(struct sock *sk, int subclass);
static inline void lock_sock(struct sock *sk)
{
lock_sock_nested(sk, 0);
}
void __lock_sock(struct sock *sk);
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) __acquires(&sk->sk_lock.slock);
/**
* 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)
__releases(&sk->sk_lock.slock)
{
if (slow) {
release_sock(sk);
__release(&sk->sk_lock.slock);
} 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);
void sock_pfree(struct sk_buff *skb);
#else
#define sock_edemux sock_efree
#endif
int sock_setsockopt(struct socket *sock, int level, int op,
sockptr_t optval, unsigned int optlen);
int sock_getsockopt(struct socket *sock, int level, int op,
char __user *optval, int __user *optlen);
int sock_gettstamp(struct socket *sock, void __user *userstamp,
bool timeval, bool time32);
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_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,
sockptr_t 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->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 (!READ_ONCE(sk->sk_dst_pending_confirm))
WRITE_ONCE(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 (READ_ONCE(n->confirmed) != now)
WRITE_ONCE(n->confirmed, now);
if (sk && READ_ONCE(sk->sk_dst_pending_confirm))
WRITE_ONCE(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_wmem_queued_add(sk, copy);
sk_mem_charge(sk, copy);
return 0;
}
/**
* sk_wmem_alloc_get - returns write allocations
* @sk: socket
*
* Return: 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
*
* Return: 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
*
* Return: 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
*
* Return: 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.
*/
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);
void sk_stop_timer_sync(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)
{
u32 val;
if (sk->sk_userlocks & SOCK_SNDBUF_LOCK)
return;
val = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
WRITE_ONCE(sk->sk_sndbuf, max_t(u32, val, 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
*
* Use the per task page_frag instead of the per socket one for
* optimization when we know that we're in the normal context and owns
* everything that's associated with %current.
*
* gfpflags_allow_blocking() isn't enough here as direct reclaim may nest
* inside other socket operations and end up recursing into sk_page_frag()
* while it's already in use.
*
* Return: a per task page_frag if context allows that,
* otherwise a per socket one.
*/
static inline struct page_frag *sk_page_frag(struct sock *sk)
{
if (gfpflags_normal_context(sk->sk_allocation))
return &current->task_frag;
return &sk->sk_frag;
}
bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag);
/*
* 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) < (READ_ONCE(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)
{
int v = waitall ? len : min_t(int, READ_ONCE(sk->sk_rcvlowat), len);
return v ?: 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 ((sizeof_field(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);
}
static inline ktime_t sock_read_timestamp(struct sock *sk)
{
#if BITS_PER_LONG==32
unsigned int seq;
ktime_t kt;
do {
seq = read_seqbegin(&sk->sk_stamp_seq);
kt = sk->sk_stamp;
} while (read_seqretry(&sk->sk_stamp_seq, seq));
return kt;
#else
return READ_ONCE(sk->sk_stamp);
#endif
}
static inline void sock_write_timestamp(struct sock *sk, ktime_t kt)
{
#if BITS_PER_LONG==32
write_seqlock(&sk->sk_stamp_seq);
sk->sk_stamp = kt;
write_sequnlock(&sk->sk_stamp_seq);
#else
WRITE_ONCE(sk->sk_stamp, kt);
#endif
}
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
sock_write_timestamp(sk, 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)))
sock_write_timestamp(sk, skb->tstamp);
else if (unlikely(sk->sk_stamp == SK_DEFAULT_STAMP))
sock_write_timestamp(sk, 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
* @tskey: filled in with next sk_tskey (not for TCP, which uses seqno)
*
* Note: callers should take care of initial ``*tx_flags`` value (usually 0)
*/
static inline void _sock_tx_timestamp(struct sock *sk, __u16 tsflags,
__u8 *tx_flags, __u32 *tskey)
{
if (unlikely(tsflags)) {
__sock_tx_timestamp(tsflags, tx_flags);
if (tsflags & SOF_TIMESTAMPING_OPT_ID && tskey &&
tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK)
*tskey = sk->sk_tskey++;
}
if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS)))
*tx_flags |= SKBTX_WIFI_STATUS;
}
static inline void sock_tx_timestamp(struct sock *sk, __u16 tsflags,
__u8 *tx_flags)
{
_sock_tx_timestamp(sk, tsflags, tx_flags, NULL);
}
static inline void skb_setup_tx_timestamp(struct sk_buff *skb, __u16 tsflags)
{
_sock_tx_timestamp(skb->sk, tsflags, &skb_shinfo(skb)->tx_flags,
&skb_shinfo(skb)->tskey);
}
DECLARE_STATIC_KEY_FALSE(tcp_rx_skb_cache_key);
/**
* 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);
if (static_branch_unlikely(&tcp_rx_skb_cache_key) &&
!sk->sk_rx_skb_cache) {
sk->sk_rx_skb_cache = skb;
skb_orphan(skb);
return;
}
__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 bool
skb_sk_is_prefetched(struct sk_buff *skb)
{
#ifdef CONFIG_INET
return skb->destructor == sock_pfree;
#else
return false;
#endif /* CONFIG_INET */
}
/* 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);
}
static inline bool
sk_is_refcounted(struct sock *sk)
{
/* Only full sockets have sk->sk_flags. */
return !sk_fullsock(sk) || !sock_flag(sk, SOCK_RCU_FREE);
}
/**
* skb_steal_sock - steal a socket from an sk_buff
* @skb: sk_buff to steal the socket from
* @refcounted: is set to true if the socket is reference-counted
*/
static inline struct sock *
skb_steal_sock(struct sk_buff *skb, bool *refcounted)
{
if (skb->sk) {
struct sock *sk = skb->sk;
*refcounted = true;
if (skb_sk_is_prefetched(skb))
*refcounted = sk_is_refcounted(sk);
skb->destructor = NULL;
skb->sk = NULL;
return sk;
}
*refcounted = false;
return NULL;
}
/* Checks if this SKB belongs to an HW offloaded socket
* and whether any SW fallbacks are required based on dev.
* Check decrypted mark in case skb_orphan() cleared socket.
*/
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);
#ifdef CONFIG_TLS_DEVICE
} else if (unlikely(skb->decrypted)) {
pr_warn_ratelimited("unencrypted skb with no associated socket - dropping\n");
kfree_skb(skb);
skb = NULL;
#endif
}
#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, enum sock_flags flag);
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;
DECLARE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
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) || READ_ONCE(sk->sk_pacing_shift) == val)
return;
WRITE_ONCE(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;
}
void sock_def_readable(struct sock *sk);
int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk);
void sock_enable_timestamps(struct sock *sk);
void sock_no_linger(struct sock *sk);
void sock_set_keepalive(struct sock *sk);
void sock_set_priority(struct sock *sk, u32 priority);
void sock_set_rcvbuf(struct sock *sk, int val);
void sock_set_mark(struct sock *sk, u32 val);
void sock_set_reuseaddr(struct sock *sk);
void sock_set_reuseport(struct sock *sk);
void sock_set_sndtimeo(struct sock *sk, s64 secs);
int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len);
#endif /* _SOCK_H */