include/net/inet_frag.h
Source file repositories/reference/linux-study-clean/include/net/inet_frag.h
File Facts
- System
- Linux kernel
- Corpus path
include/net/inet_frag.h- Extension
.h- Size
- 5062 bytes
- Lines
- 183
- 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/rhashtable-types.hlinux/completion.hlinux/in6.hlinux/rbtree_types.hlinux/refcount.hnet/dropreason-core.h
Detected Declarations
struct fqdirstruct frag_v4_compare_keystruct frag_v6_compare_keystruct inet_frag_queuestruct inet_fragsfunction inet_frag_putnfunction frag_mem_limitfunction sub_frag_mem_limitfunction add_frag_mem_limit
Annotated Snippet
struct fqdir {
/* sysctls */
long high_thresh;
long low_thresh;
int timeout;
int max_dist;
struct inet_frags *f;
struct net *net;
bool dead;
struct rhashtable rhashtable ____cacheline_aligned_in_smp;
/* Keep atomic mem on separate cachelines in structs that include it */
atomic_long_t mem ____cacheline_aligned_in_smp;
struct work_struct destroy_work;
struct llist_node free_list;
};
/**
* enum: fragment queue flags
*
* @INET_FRAG_FIRST_IN: first fragment has arrived
* @INET_FRAG_LAST_IN: final fragment has arrived
* @INET_FRAG_COMPLETE: frag queue has been processed and is due for destruction
* @INET_FRAG_HASH_DEAD: inet_frag_kill() has not removed fq from rhashtable
* @INET_FRAG_DROP: if skbs must be dropped (instead of being consumed)
*/
enum {
INET_FRAG_FIRST_IN = BIT(0),
INET_FRAG_LAST_IN = BIT(1),
INET_FRAG_COMPLETE = BIT(2),
INET_FRAG_HASH_DEAD = BIT(3),
INET_FRAG_DROP = BIT(4),
};
struct frag_v4_compare_key {
__be32 saddr;
__be32 daddr;
u32 user;
u32 vif;
__be16 id;
u16 protocol;
};
struct frag_v6_compare_key {
struct in6_addr saddr;
struct in6_addr daddr;
u32 user;
__be32 id;
u32 iif;
};
/**
* struct inet_frag_queue - fragment queue
*
* @node: rhash node
* @key: keys identifying this frag.
* @timer: queue expiration timer
* @lock: spinlock protecting this frag
* @refcnt: reference count of the queue
* @rb_fragments: received fragments rb-tree root
* @fragments_tail: received fragments tail
* @last_run_head: the head of the last "run". see ip_fragment.c
* @stamp: timestamp of the last received fragment
* @len: total length of the original datagram
* @meat: length of received fragments so far
* @tstamp_type: stamp has a mono delivery time (EDT)
* @flags: fragment queue flags
* @max_size: maximum received fragment size
* @fqdir: pointer to struct fqdir
* @rcu: rcu head for freeing deferall
*/
struct inet_frag_queue {
struct rhash_head node;
union {
struct frag_v4_compare_key v4;
struct frag_v6_compare_key v6;
} key;
struct timer_list timer;
spinlock_t lock;
refcount_t refcnt;
struct rb_root rb_fragments;
struct sk_buff *fragments_tail;
struct sk_buff *last_run_head;
ktime_t stamp;
int len;
int meat;
u8 tstamp_type;
__u8 flags;
u16 max_size;
Annotation
- Immediate include surface: `linux/rhashtable-types.h`, `linux/completion.h`, `linux/in6.h`, `linux/rbtree_types.h`, `linux/refcount.h`, `net/dropreason-core.h`.
- Detected declarations: `struct fqdir`, `struct frag_v4_compare_key`, `struct frag_v6_compare_key`, `struct inet_frag_queue`, `struct inet_frags`, `function inet_frag_putn`, `function frag_mem_limit`, `function sub_frag_mem_limit`, `function add_frag_mem_limit`.
- 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.