net_device 구조체 필드 정리

struct net_device {
	char			name[IFNAMSIZ];
	struct netdev_name_node	*name_node;
	struct dev_ifalias	__rcu *ifalias;
	/*
	 *	I/O specific fields
	 *	FIXME: Merge these and struct ifmap into one
	 */
	unsigned long		mem_end;
	unsigned long		mem_start;
	unsigned long		base_addr;
	int			irq;

	/*
	 *	Some hardware also needs these fields (state,dev_list,
	 *	napi_list,unreg_list,close_list) but they are not
	 *	part of the usual set specified in Space.c.
	 */

	unsigned long		state;

	struct list_head	dev_list;
	struct list_head	napi_list;
	struct list_head	unreg_list;
	struct list_head	close_list;
	struct list_head	ptype_all;
	struct list_head	ptype_specific;

	struct {
		struct list_head upper;
		struct list_head lower;
	} adj_list;

	netdev_features_t	features;
	netdev_features_t	hw_features;
	netdev_features_t	wanted_features;
	netdev_features_t	vlan_features;
	netdev_features_t	hw_enc_features;
	netdev_features_t	mpls_features;
	netdev_features_t	gso_partial_features;

	int			ifindex;
	int			group;

	struct net_device_stats	stats;

	atomic_long_t		rx_dropped;
	atomic_long_t		tx_dropped;
	atomic_long_t		rx_nohandler;

	/* Stats to monitor link on/off, flapping */
	atomic_t		carrier_up_count;
	atomic_t		carrier_down_count;

#ifdef CONFIG_WIRELESS_EXT
	const struct iw_handler_def *wireless_handlers;
	struct iw_public_data	*wireless_data;
#endif
	const struct net_device_ops *netdev_ops;
	const struct ethtool_ops *ethtool_ops;
#ifdef CONFIG_NET_L3_MASTER_DEV
	const struct l3mdev_ops	*l3mdev_ops;
#endif
#if IS_ENABLED(CONFIG_IPV6)
	const struct ndisc_ops *ndisc_ops;
#endif

#ifdef CONFIG_XFRM_OFFLOAD
	const struct xfrmdev_ops *xfrmdev_ops;
#endif

#if IS_ENABLED(CONFIG_TLS_DEVICE)
	const struct tlsdev_ops *tlsdev_ops;
#endif

	const struct header_ops *header_ops;

	unsigned int		flags;
	unsigned int		priv_flags;

	unsigned short		gflags;
	unsigned short		padded;

	unsigned char		operstate;
	unsigned char		link_mode;

	unsigned char		if_port;
	unsigned char		dma;

	/* Note : dev->mtu is often read without holding a lock.
	 * Writers usually hold RTNL.
	 * It is recommended to use READ_ONCE() to annotate the reads,
	 * and to use WRITE_ONCE() to annotate the writes.
	 */
	unsigned int		mtu;
	unsigned int		min_mtu;
	unsigned int		max_mtu;
	unsigned short		type;
	unsigned short		hard_header_len;
	unsigned char		min_header_len;
	unsigned char		name_assign_type;

	unsigned short		needed_headroom;
	unsigned short		needed_tailroom;

	/* Interface address info. */
	unsigned char		perm_addr[MAX_ADDR_LEN];
	unsigned char		addr_assign_type;
	unsigned char		addr_len;
	unsigned char		upper_level;
	unsigned char		lower_level;

	unsigned short		neigh_priv_len;
	unsigned short          dev_id;
	unsigned short          dev_port;
	spinlock_t		addr_list_lock;

	struct netdev_hw_addr_list	uc;
	struct netdev_hw_addr_list	mc;
	struct netdev_hw_addr_list	dev_addrs;

#ifdef CONFIG_SYSFS
	struct kset		*queues_kset;
#endif
#ifdef CONFIG_LOCKDEP
	struct list_head	unlink_list;
#endif
	unsigned int		promiscuity;
	unsigned int		allmulti;
	bool			uc_promisc;
#ifdef CONFIG_LOCKDEP
	unsigned char		nested_level;
#endif


	/* Protocol-specific pointers */

#if IS_ENABLED(CONFIG_VLAN_8021Q)
	struct vlan_info __rcu	*vlan_info;
#endif
#if IS_ENABLED(CONFIG_NET_DSA)
	struct dsa_port		*dsa_ptr;
#endif
#if IS_ENABLED(CONFIG_TIPC)
	struct tipc_bearer __rcu *tipc_ptr;
#endif
#if IS_ENABLED(CONFIG_IRDA) || IS_ENABLED(CONFIG_ATALK)
	void 			*atalk_ptr;
#endif
	struct in_device __rcu	*ip_ptr;
#if IS_ENABLED(CONFIG_DECNET)
	struct dn_dev __rcu     *dn_ptr;
#endif
	struct inet6_dev __rcu	*ip6_ptr;
#if IS_ENABLED(CONFIG_AX25)
	void			*ax25_ptr;
#endif
	struct wireless_dev	*ieee80211_ptr;
	struct wpan_dev		*ieee802154_ptr;
#if IS_ENABLED(CONFIG_MPLS_ROUTING)
	struct mpls_dev __rcu	*mpls_ptr;
#endif

/*
 * Cache lines mostly used on receive path (including eth_type_trans())
 */
	/* Interface address info used in eth_type_trans() */
	unsigned char		*dev_addr;

	struct netdev_rx_queue	*_rx;
	unsigned int		num_rx_queues;
	unsigned int		real_num_rx_queues;

	struct bpf_prog __rcu	*xdp_prog;
	unsigned long		gro_flush_timeout;
	int			napi_defer_hard_irqs;
	rx_handler_func_t __rcu	*rx_handler;
	void __rcu		*rx_handler_data;

#ifdef CONFIG_NET_CLS_ACT
	struct mini_Qdisc __rcu	*miniq_ingress;
#endif
	struct netdev_queue __rcu *ingress_queue;
#ifdef CONFIG_NETFILTER_INGRESS
	struct nf_hook_entries __rcu *nf_hooks_ingress;
#endif

	unsigned char		broadcast[MAX_ADDR_LEN];
#ifdef CONFIG_RFS_ACCEL
	struct cpu_rmap		*rx_cpu_rmap;
#endif
	struct hlist_node	index_hlist;

/*
 * Cache lines mostly used on transmit path
 */
	struct netdev_queue	*_tx ____cacheline_aligned_in_smp;
	unsigned int		num_tx_queues;
	unsigned int		real_num_tx_queues;
	struct Qdisc		*qdisc;
	unsigned int		tx_queue_len;
	spinlock_t		tx_global_lock;

	struct xdp_dev_bulk_queue __percpu *xdp_bulkq;

#ifdef CONFIG_XPS
	struct xps_dev_maps __rcu *xps_cpus_map;
	struct xps_dev_maps __rcu *xps_rxqs_map;
#endif
#ifdef CONFIG_NET_CLS_ACT
	struct mini_Qdisc __rcu	*miniq_egress;
#endif

#ifdef CONFIG_NET_SCHED
	DECLARE_HASHTABLE	(qdisc_hash, 4);
#endif
	/* These may be needed for future network-power-down code. */
	struct timer_list	watchdog_timer;
	int			watchdog_timeo;

	u32                     proto_down_reason;

	struct list_head	todo_list;
	int __percpu		*pcpu_refcnt;

	struct list_head	link_watch_list;

	enum { NETREG_UNINITIALIZED=0,
	       NETREG_REGISTERED,	/* completed register_netdevice */
	       NETREG_UNREGISTERING,	/* called unregister_netdevice */
	       NETREG_UNREGISTERED,	/* completed unregister todo */
	       NETREG_RELEASED,		/* called free_netdev */
	       NETREG_DUMMY,		/* dummy device for NAPI poll */
	} reg_state:8;

	bool dismantle;

	enum {
		RTNL_LINK_INITIALIZED,
		RTNL_LINK_INITIALIZING,
	} rtnl_link_state:16;

	bool needs_free_netdev;
	void (*priv_destructor)(struct net_device *dev);

#ifdef CONFIG_NETPOLL
	struct netpoll_info __rcu	*npinfo;
#endif

	possible_net_t			nd_net;

	/* mid-layer private */
	union {
		void					*ml_priv;
		struct pcpu_lstats __percpu		*lstats;
		struct pcpu_sw_netstats __percpu	*tstats;
		struct pcpu_dstats __percpu		*dstats;
	};

#if IS_ENABLED(CONFIG_GARP)
	struct garp_port __rcu	*garp_port;
#endif
#if IS_ENABLED(CONFIG_MRP)
	struct mrp_port __rcu	*mrp_port;
#endif

	struct device		dev;
	const struct attribute_group *sysfs_groups[4];
	const struct attribute_group *sysfs_rx_queue_group;

	const struct rtnl_link_ops *rtnl_link_ops;

	/* for setting kernel sock attribute on TCP connection setup */
#define GSO_MAX_SIZE		65536
	unsigned int		gso_max_size;
#define GSO_MAX_SEGS		65535
	u16			gso_max_segs;

#ifdef CONFIG_DCB
	const struct dcbnl_rtnl_ops *dcbnl_ops;
#endif
	s16			num_tc;
	struct netdev_tc_txq	tc_to_txq[TC_MAX_QUEUE];
	u8			prio_tc_map[TC_BITMASK + 1];

#if IS_ENABLED(CONFIG_FCOE)
	unsigned int		fcoe_ddp_xid;
#endif
#if IS_ENABLED(CONFIG_CGROUP_NET_PRIO)
	struct netprio_map __rcu *priomap;
#endif
	struct phy_device	*phydev;
	struct sfp_bus		*sfp_bus;
	struct lock_class_key	*qdisc_tx_busylock;
	struct lock_class_key	*qdisc_running_key;
	bool			proto_down;
	unsigned		wol_enabled:1;

	struct list_head	net_notifier_list;

#if IS_ENABLED(CONFIG_MACSEC)
	/* MACsec management functions */
	const struct macsec_ops *macsec_ops;
#endif
	const struct udp_tunnel_nic_info	*udp_tunnel_nic_info;
	struct udp_tunnel_nic	*udp_tunnel_nic;

	/* protected by rtnl_lock */
	struct bpf_xdp_entity	xdp_state[__MAX_XDP_MODE];
};