include/net/x25.h

File Facts

System

Linux kernel

Corpus path

include/net/x25.h

Extension

.h

Size

9642 bytes

Lines

324

Domain

Networking Core

Bucket

Sockets, Protocols, Packet Path, And Network Policy

Inferred role

Networking Core: implementation source

Status

source implementation candidate

Why This File Exists

Networking stack implementation surface: socket APIs, protocol dispatch, packet flow, routing, filtering, and network namespaces.

• Networking stack implementation surface: socket APIs, protocol dispatch, packet flow, routing, filtering, and network namespaces.
• Uses kernel synchronization; read lock ordering, sleepability, and interrupt context assumptions before translating.
• Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

• linux/x25.h
• linux/slab.h
• linux/refcount.h
• net/sock.h

Detected Declarations

• struct x25_route
• struct x25_neigh
• struct x25_sock
• struct x25_forward
• struct x25_skb_cb
• function x25_neigh_hold
• function x25_neigh_put
• function x25_route_hold
• function x25_route_put
• function x25_register_sysctl
• function x25_unregister_sysctl

Annotated Snippet

struct x25_route {
	struct list_head	node;		
	struct x25_address	address;
	unsigned int		sigdigits;
	struct net_device	*dev;
	refcount_t		refcnt;
};

struct x25_neigh {
	struct list_head	node;
	struct net_device	*dev;
	unsigned int		state;
	unsigned int		extended;
	struct sk_buff_head	queue;
	unsigned long		t20;
	struct timer_list	t20timer;
	unsigned long		global_facil_mask;
	refcount_t		refcnt;
};

struct x25_sock {
	struct sock		sk;
	struct x25_address	source_addr, dest_addr;
	struct x25_neigh	*neighbour;
	unsigned int		lci, cudmatchlength;
	unsigned char		state, condition;
	unsigned short		vs, vr, va, vl;
	unsigned long		t2, t21, t22, t23;
	unsigned short		fraglen;
	unsigned long		flags;
	struct sk_buff_head	ack_queue;
	struct sk_buff_head	fragment_queue;
	struct sk_buff_head	interrupt_in_queue;
	struct sk_buff_head	interrupt_out_queue;
	struct timer_list	timer;
	struct x25_causediag	causediag;
	struct x25_facilities	facilities;
	struct x25_dte_facilities dte_facilities;
	struct x25_calluserdata	calluserdata;
	unsigned long 		vc_facil_mask;	/* inc_call facilities mask */
};

struct x25_forward {
	struct list_head	node;
	unsigned int		lci;
	struct net_device	*dev1;
	struct net_device	*dev2;
	atomic_t		refcnt;
};

#define x25_sk(ptr) container_of_const(ptr, struct x25_sock, sk)

/* af_x25.c */
extern int  sysctl_x25_restart_request_timeout;
extern int  sysctl_x25_call_request_timeout;
extern int  sysctl_x25_reset_request_timeout;
extern int  sysctl_x25_clear_request_timeout;
extern int  sysctl_x25_ack_holdback_timeout;
extern int  sysctl_x25_forward;

int x25_parse_address_block(struct sk_buff *skb,
			    struct x25_address *called_addr,
			    struct x25_address *calling_addr);

int x25_addr_ntoa(unsigned char *, struct x25_address *, struct x25_address *);
int x25_addr_aton(unsigned char *, struct x25_address *, struct x25_address *);
struct sock *x25_find_socket(unsigned int, struct x25_neigh *);
void x25_destroy_socket_from_timer(struct sock *);
int x25_rx_call_request(struct sk_buff *, struct x25_neigh *, unsigned int);
void x25_kill_by_neigh(struct x25_neigh *);

/* x25_dev.c */
void x25_send_frame(struct sk_buff *, struct x25_neigh *);
int x25_lapb_receive_frame(struct sk_buff *, struct net_device *,
			   struct packet_type *, struct net_device *);
void x25_establish_link(struct x25_neigh *);

/* x25_facilities.c */
int x25_parse_facilities(struct sk_buff *, struct x25_facilities *,
			 struct x25_dte_facilities *, unsigned long *);
int x25_create_facilities(unsigned char *, struct x25_facilities *,
			  struct x25_dte_facilities *, unsigned long);
int x25_negotiate_facilities(struct sk_buff *, struct sock *,
			     struct x25_facilities *,
			     struct x25_dte_facilities *);
void x25_limit_facilities(struct x25_facilities *, struct x25_neigh *);

/* x25_forward.c */
void x25_clear_forward_by_lci(unsigned int lci);
void x25_clear_forward_by_dev(struct net_device *);

Annotation

• Immediate include surface: `linux/x25.h`, `linux/slab.h`, `linux/refcount.h`, `net/sock.h`.
• Detected declarations: `struct x25_route`, `struct x25_neigh`, `struct x25_sock`, `struct x25_forward`, `struct x25_skb_cb`, `function x25_neigh_hold`, `function x25_neigh_put`, `function x25_route_hold`, `function x25_route_put`, `function x25_register_sysctl`.
• Atlas domain: Networking Core / Sockets, Protocols, Packet Path, And Network Policy.
• Implementation status: source implementation candidate.
• Synchronization appears in or near this file; preserve lock ordering, sleepability, and interrupt-context constraints.

Implementation Notes

• This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
• Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
• Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.