net/mptcp/bpf.c
Source file repositories/reference/linux-study-clean/net/mptcp/bpf.c
File Facts
- System
- Linux kernel
- Corpus path
net/mptcp/bpf.c- Extension
.c- Size
- 855 bytes
- Lines
- 37
- 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.
- Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.
Dependency Surface
linux/bpf.hprotocol.h
Detected Declarations
function Copyrightfunction bpf_mptcp_kfunc_init
Annotated Snippet
// SPDX-License-Identifier: GPL-2.0
/* Multipath TCP
*
* Copyright (c) 2020, Tessares SA.
* Copyright (c) 2022, SUSE.
*
* Author: Nicolas Rybowski <nicolas.rybowski@tessares.net>
*/
#define pr_fmt(fmt) "MPTCP: " fmt
#include <linux/bpf.h>
#include "protocol.h"
struct mptcp_sock *bpf_mptcp_sock_from_subflow(struct sock *sk)
{
if (sk && sk_fullsock(sk) && sk_is_tcp(sk) && sk_is_mptcp(sk))
return mptcp_sk(mptcp_subflow_ctx(sk)->conn);
return NULL;
}
BTF_SET8_START(bpf_mptcp_fmodret_ids)
BTF_ID_FLAGS(func, update_socket_protocol)
BTF_SET8_END(bpf_mptcp_fmodret_ids)
static const struct btf_kfunc_id_set bpf_mptcp_fmodret_set = {
.owner = THIS_MODULE,
.set = &bpf_mptcp_fmodret_ids,
};
static int __init bpf_mptcp_kfunc_init(void)
{
return register_btf_fmodret_id_set(&bpf_mptcp_fmodret_set);
}
late_initcall(bpf_mptcp_kfunc_init);
Annotation
- Immediate include surface: `linux/bpf.h`, `protocol.h`.
- Detected declarations: `function Copyright`, `function bpf_mptcp_kfunc_init`.
- Atlas domain: Networking Core / Sockets, Protocols, Packet Path, And Network Policy.
- Implementation status: source implementation candidate.
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.