net/mpls/af_mpls.c

File Facts

System

Linux kernel

Corpus path

net/mpls/af_mpls.c

Extension

.c

Size

67182 bytes

Lines

2893

Domain

Networking Core

Bucket

Sockets, Protocols, Packet Path, And Network Policy

Inferred role

Networking Core: exported/initcall integration point

Status

integration 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.
• Exports symbols or registers init work; inspect boot/module ordering and who consumes the exported contract.
• Uses kernel synchronization; read lock ordering, sleepability, and interrupt context assumptions before translating.
• Touches IRQ or DMA behavior; this matters for the representative real-device path.
• Allocates kernel memory; connect allocation flags and lifetime to context constraints.
• Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

• linux/types.h
• linux/skbuff.h
• linux/socket.h
• linux/sysctl.h
• linux/net.h
• linux/module.h
• linux/if_arp.h
• linux/ipv6.h
• linux/mpls.h
• linux/netconf.h
• linux/nospec.h
• linux/vmalloc.h
• linux/percpu.h
• net/gso.h
• net/ip.h
• net/dst.h
• net/sock.h
• net/arp.h
• net/ip_fib.h
• net/netevent.h
• net/ip_tunnels.h
• net/netns/generic.h
• net/ipv6.h
• net/rtnh.h
• internal.h

Detected Declarations

• struct mpls_route_config
• function ipgre_mpls_encap_hlen
• function ipgre_tunnel_encap_add_mpls_ops
• function ipgre_tunnel_encap_del_mpls_ops
• function ipgre_tunnel_encap_add_mpls_ops
• function ipgre_tunnel_encap_del_mpls_ops
• function mpls_output_possible
• function mpls_nh_header_size
• function mpls_dev_mtu
• function mpls_pkt_too_big
• function mpls_stats_inc_outucastpkts
• function mpls_multipath_hash
• function pskb_may_pull
• function hop
• function mpls_egress
• function mpls_forward
• function mpls_rt_free_rcu
• function change_nexthops
• function mpls_rt_free
• function mpls_notify_route
• function mpls_route_update
• function find_free_label
• function mpls_nh_assign_dev
• function nla_get_via
• function mpls_nh_build_from_cfg
• function mpls_nh_build
• function mpls_count_nexthops
• function mpls_nh_build_multi
• function change_nexthops
• function mpls_label_ok
• function mpls_route_add
• function mpls_route_del
• function mpls_get_stats
• function for_each_possible_cpu
• function mpls_fill_stats_af
• function mpls_get_stats_af_size
• function mpls_netconf_fill_devconf
• function mpls_netconf_msgsize_devconf
• function mpls_netconf_notify_devconf
• function mpls_netconf_valid_get_req
• function mpls_netconf_get_devconf
• function mpls_netconf_dump_devconf
• function mpls_conf_proc
• function mpls_dev_sysctl_register
• function mpls_dev_sysctl_unregister
• function for_each_possible_cpu
• function mpls_dev_destroy_rcu
• function mpls_ifdown

Annotated Snippet

module_init(mpls_init);

static void __exit mpls_exit(void)
{
	rtnl_unregister_all(PF_MPLS);
	rtnl_af_unregister(&mpls_af_ops);
	dev_remove_pack(&mpls_packet_type);
	unregister_netdevice_notifier(&mpls_dev_notifier);
	unregister_pernet_subsys(&mpls_net_ops);
	ipgre_tunnel_encap_del_mpls_ops();
}
module_exit(mpls_exit);

MODULE_DESCRIPTION("MultiProtocol Label Switching");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS_NETPROTO(PF_MPLS);

Annotation

• Immediate include surface: `linux/types.h`, `linux/skbuff.h`, `linux/socket.h`, `linux/sysctl.h`, `linux/net.h`, `linux/module.h`, `linux/if_arp.h`, `linux/ipv6.h`.
• Detected declarations: `struct mpls_route_config`, `function ipgre_mpls_encap_hlen`, `function ipgre_tunnel_encap_add_mpls_ops`, `function ipgre_tunnel_encap_del_mpls_ops`, `function ipgre_tunnel_encap_add_mpls_ops`, `function ipgre_tunnel_encap_del_mpls_ops`, `function mpls_output_possible`, `function mpls_nh_header_size`, `function mpls_dev_mtu`, `function mpls_pkt_too_big`.
• Atlas domain: Networking Core / Sockets, Protocols, Packet Path, And Network Policy.
• Implementation status: integration implementation candidate.
• Synchronization appears in or near this file; preserve lock ordering, sleepability, and interrupt-context constraints.
• IRQ or DMA behavior appears here, which is relevant to the selected PCIe/NVMe device path.

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.