include/net/flow.h
Source file repositories/reference/linux-study-clean/include/net/flow.h
File Facts
- System
- Linux kernel
- Corpus path
include/net/flow.h- Extension
.h- Size
- 5207 bytes
- Lines
- 199
- 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/in6.hlinux/atomic.hlinux/container_of.hlinux/uidgid.hnet/inet_dscp.h
Detected Declarations
struct flow_keysstruct flowi_tunnelstruct flowi_commonstruct flowi4struct flowi6struct flowifunction flowi4_init_outputfunction flowi4_update_output
Annotated Snippet
struct flowi_tunnel {
__be64 tun_id;
};
struct flowi_common {
int flowic_oif;
int flowic_iif;
int flowic_l3mdev;
__u32 flowic_mark;
dscp_t flowic_dscp;
__u8 flowic_scope;
__u8 flowic_proto;
__u8 flowic_flags;
#define FLOWI_FLAG_ANYSRC 0x01
#define FLOWI_FLAG_KNOWN_NH 0x02
#define FLOWI_FLAG_L3MDEV_OIF 0x04
#define FLOWI_FLAG_ANY_SPORT 0x08
__u32 flowic_secid;
kuid_t flowic_uid;
__u32 flowic_multipath_hash;
struct flowi_tunnel flowic_tun_key;
};
union flowi_uli {
struct {
__be16 dport;
__be16 sport;
} ports;
struct {
__u8 type;
__u8 code;
} icmpt;
__be32 gre_key;
struct {
__u8 type;
} mht;
};
struct flowi4 {
struct flowi_common __fl_common;
#define flowi4_oif __fl_common.flowic_oif
#define flowi4_iif __fl_common.flowic_iif
#define flowi4_l3mdev __fl_common.flowic_l3mdev
#define flowi4_mark __fl_common.flowic_mark
#define flowi4_dscp __fl_common.flowic_dscp
#define flowi4_scope __fl_common.flowic_scope
#define flowi4_proto __fl_common.flowic_proto
#define flowi4_flags __fl_common.flowic_flags
#define flowi4_secid __fl_common.flowic_secid
#define flowi4_tun_key __fl_common.flowic_tun_key
#define flowi4_uid __fl_common.flowic_uid
#define flowi4_multipath_hash __fl_common.flowic_multipath_hash
/* (saddr,daddr) must be grouped, same order as in IP header */
__be32 saddr;
__be32 daddr;
union flowi_uli uli;
#define fl4_sport uli.ports.sport
#define fl4_dport uli.ports.dport
#define fl4_icmp_type uli.icmpt.type
#define fl4_icmp_code uli.icmpt.code
#define fl4_mh_type uli.mht.type
#define fl4_gre_key uli.gre_key
} __attribute__((__aligned__(BITS_PER_LONG/8)));
static inline void flowi4_init_output(struct flowi4 *fl4, int oif,
__u32 mark, __u8 tos, __u8 scope,
__u8 proto, __u8 flags,
__be32 daddr, __be32 saddr,
__be16 dport, __be16 sport,
kuid_t uid)
{
fl4->flowi4_oif = oif;
fl4->flowi4_iif = LOOPBACK_IFINDEX;
fl4->flowi4_l3mdev = 0;
fl4->flowi4_mark = mark;
fl4->flowi4_dscp = inet_dsfield_to_dscp(tos);
fl4->flowi4_scope = scope;
fl4->flowi4_proto = proto;
fl4->flowi4_flags = flags;
fl4->flowi4_secid = 0;
fl4->flowi4_tun_key.tun_id = 0;
fl4->flowi4_uid = uid;
fl4->daddr = daddr;
fl4->saddr = saddr;
fl4->fl4_dport = dport;
Annotation
- Immediate include surface: `linux/in6.h`, `linux/atomic.h`, `linux/container_of.h`, `linux/uidgid.h`, `net/inet_dscp.h`.
- Detected declarations: `struct flow_keys`, `struct flowi_tunnel`, `struct flowi_common`, `struct flowi4`, `struct flowi6`, `struct flowi`, `function flowi4_init_output`, `function flowi4_update_output`.
- 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.