net/nfc/llcp_sock.c
Source file repositories/reference/linux-study-clean/net/nfc/llcp_sock.c
File Facts
- System
- Linux kernel
- Corpus path
net/nfc/llcp_sock.c- Extension
.c- Size
- 22971 bytes
- Lines
- 1069
- Domain
- Networking Core
- Bucket
- Sockets, Protocols, Packet Path, And Network Policy
- Inferred role
- Networking Core: operation-table or driver-model contract
- Status
- pattern 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.
- Defines an operation table; this is where Linux turns generic core objects into subsystem-specific behavior.
- Touches user memory; correctness depends on fault-safe copying and privilege boundary handling.
- Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.
Dependency Surface
linux/init.hlinux/kernel.hlinux/module.hlinux/nfc.hlinux/sched/signal.hnfc.hllcp.h
Detected Declarations
function Copyrightfunction llcp_sock_bindfunction llcp_raw_sock_bindfunction llcp_sock_listenfunction nfc_llcp_setsockoptfunction nfc_llcp_getsockoptfunction nfc_llcp_accept_unlinkfunction nfc_llcp_accept_enqueuefunction list_for_each_entry_safefunction llcp_sock_acceptfunction llcp_sock_getnamefunction llcp_accept_pollfunction list_for_each_entryfunction llcp_sock_pollfunction llcp_sock_releasefunction list_for_each_entry_safefunction llcp_sock_connectfunction llcp_sock_sendmsgfunction llcp_sock_recvmsgfunction llcp_sock_destructfunction nfc_llcp_sock_freefunction llcp_sock_createfunction nfc_llcp_sock_initfunction nfc_llcp_sock_exit
Annotated Snippet
static const struct proto_ops llcp_sock_ops = {
.family = PF_NFC,
.owner = THIS_MODULE,
.bind = llcp_sock_bind,
.connect = llcp_sock_connect,
.release = llcp_sock_release,
.socketpair = sock_no_socketpair,
.accept = llcp_sock_accept,
.getname = llcp_sock_getname,
.poll = llcp_sock_poll,
.ioctl = sock_no_ioctl,
.listen = llcp_sock_listen,
.shutdown = sock_no_shutdown,
.setsockopt = nfc_llcp_setsockopt,
.getsockopt = nfc_llcp_getsockopt,
.sendmsg = llcp_sock_sendmsg,
.recvmsg = llcp_sock_recvmsg,
.mmap = sock_no_mmap,
};
static const struct proto_ops llcp_rawsock_ops = {
.family = PF_NFC,
.owner = THIS_MODULE,
.bind = llcp_raw_sock_bind,
.connect = sock_no_connect,
.release = llcp_sock_release,
.socketpair = sock_no_socketpair,
.accept = sock_no_accept,
.getname = llcp_sock_getname,
.poll = llcp_sock_poll,
.ioctl = sock_no_ioctl,
.listen = sock_no_listen,
.shutdown = sock_no_shutdown,
.sendmsg = sock_no_sendmsg,
.recvmsg = llcp_sock_recvmsg,
.mmap = sock_no_mmap,
};
static void llcp_sock_destruct(struct sock *sk)
{
struct nfc_llcp_sock *llcp_sock = nfc_llcp_sock(sk);
pr_debug("%p\n", sk);
if (sk->sk_state == LLCP_CONNECTED)
nfc_put_device(llcp_sock->dev);
skb_queue_purge(&sk->sk_receive_queue);
nfc_llcp_sock_free(llcp_sock);
if (!sock_flag(sk, SOCK_DEAD)) {
pr_err("Freeing alive NFC LLCP socket %p\n", sk);
return;
}
}
struct sock *nfc_llcp_sock_alloc(struct socket *sock, int type, gfp_t gfp, int kern)
{
struct sock *sk;
struct nfc_llcp_sock *llcp_sock;
sk = sk_alloc(&init_net, PF_NFC, gfp, &llcp_sock_proto, kern);
if (!sk)
return NULL;
llcp_sock = nfc_llcp_sock(sk);
sock_init_data(sock, sk);
sk->sk_state = LLCP_CLOSED;
sk->sk_protocol = NFC_SOCKPROTO_LLCP;
sk->sk_type = type;
sk->sk_destruct = llcp_sock_destruct;
llcp_sock->ssap = 0;
llcp_sock->dsap = LLCP_SAP_SDP;
llcp_sock->rw = LLCP_MAX_RW + 1;
llcp_sock->miux = cpu_to_be16(LLCP_MAX_MIUX + 1);
llcp_sock->send_n = llcp_sock->send_ack_n = 0;
llcp_sock->recv_n = llcp_sock->recv_ack_n = 0;
llcp_sock->remote_ready = 1;
llcp_sock->reserved_ssap = LLCP_SAP_MAX;
nfc_llcp_socket_remote_param_init(llcp_sock);
skb_queue_head_init(&llcp_sock->tx_queue);
skb_queue_head_init(&llcp_sock->tx_pending_queue);
INIT_LIST_HEAD(&llcp_sock->accept_queue);
if (sock != NULL)
sock->state = SS_UNCONNECTED;
Annotation
- Immediate include surface: `linux/init.h`, `linux/kernel.h`, `linux/module.h`, `linux/nfc.h`, `linux/sched/signal.h`, `nfc.h`, `llcp.h`.
- Detected declarations: `function Copyright`, `function llcp_sock_bind`, `function llcp_raw_sock_bind`, `function llcp_sock_listen`, `function nfc_llcp_setsockopt`, `function nfc_llcp_getsockopt`, `function nfc_llcp_accept_unlink`, `function nfc_llcp_accept_enqueue`, `function list_for_each_entry_safe`, `function llcp_sock_accept`.
- Atlas domain: Networking Core / Sockets, Protocols, Packet Path, And Network Policy.
- Implementation status: pattern implementation candidate.
- This snippet crosses the user/kernel memory boundary; validate fault handling and access checks before translating the pattern.
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.