include/net/af_unix.h

File Facts

System

Linux kernel

Corpus path

include/net/af_unix.h

Extension

.h

Size

1405 bytes

Lines

64

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/atomic.h
• linux/mutex.h
• linux/net.h
• linux/path.h
• linux/refcount.h
• linux/spinlock.h
• linux/wait.h
• net/sock.h
• uapi/linux/un.h

Detected Declarations

• struct unix_address
• struct scm_stat
• struct unix_sock

Annotated Snippet

struct unix_address {
	refcount_t	refcnt;
	int		len;
	struct sockaddr_un name[];
};

struct scm_stat {
	atomic_t nr_fds;
	unsigned long nr_unix_fds;
};

/* The AF_UNIX socket */
struct unix_sock {
	/* WARNING: sk has to be the first member */
	struct sock		sk;
	struct unix_address	*addr;
	struct path		path;
	struct mutex		iolock, bindlock;
	struct sock		*peer;
	struct sock		*listener;
	struct unix_vertex	*vertex;
	spinlock_t		lock;
	struct socket_wq	peer_wq;
#define peer_wait		peer_wq.wait
	wait_queue_entry_t	peer_wake;
	struct scm_stat		scm_stat;
	int			inq_len;
	bool			recvmsg_inq;
#if IS_ENABLED(CONFIG_AF_UNIX_OOB)
	struct sk_buff		*oob_skb;
#endif
};

#define unix_sk(ptr) container_of_const(ptr, struct unix_sock, sk)
#define unix_peer(sk) (unix_sk(sk)->peer)

#define unix_state_lock(s)	spin_lock(&unix_sk(s)->lock)
#define unix_state_unlock(s)	spin_unlock(&unix_sk(s)->lock)

#endif

Annotation

• Immediate include surface: `linux/atomic.h`, `linux/mutex.h`, `linux/net.h`, `linux/path.h`, `linux/refcount.h`, `linux/spinlock.h`, `linux/wait.h`, `net/sock.h`.
• Detected declarations: `struct unix_address`, `struct scm_stat`, `struct unix_sock`.
• 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.