netdevice.h

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/*
 * INET		An implementation of the TCP/IP protocol suite for the LINUX
 *		operating system.  INET is implemented using the  BSD Socket
 *		interface as the means of communication with the user level.
 *
 *		Definitions for the Interfaces handler.
 *
 * Version:	@(#)dev.h	1.0.10	08/12/93
 *
 * Authors:	Ross Biro, <[e-mail]>
 *		Fred N. van Kempen, <[e-mail]>
 *		Corey Minyard <wf-rch![e-mail]>
 *		Donald J. Becker, <[e-mail]>
 *		Alan Cox, <[e-mail]>
 *		Bjorn Ekwall. <[e-mail]>
 *              Pekka Riikonen <[e-mail]>
 *
 *		This program is free software; you can redistribute it and/or
 *		modify it under the terms of the GNU General Public License
 *		as published by the Free Software Foundation; either version
 *		2 of the License, or (at your option) any later version.
 *
 *		Moved to /usr/include/linux for NET3
 */
#ifndef _LINUX_NETDEVICE_H
#define _LINUX_NETDEVICE_H

#include <linux/if.h>
#include <linux/if_ether.h>
#include <linux/if_packet.h>

#include <asm/atomic.h>
#include <asm/cache.h>
#include <asm/byteorder.h>

#ifdef __KERNEL__
#include <linux/config.h>
#ifdef CONFIG_NET_PROFILE
#include <net/profile.h>
#endif

struct divert_blk;

#define NET_XMIT_SUCCESS	0
#define NET_XMIT_DROP		1	/* skb dropped			*/
#define NET_XMIT_CN		2	/* congestion notification	*/
#define NET_XMIT_POLICED	3	/* skb is shot by police	*/
#define NET_XMIT_BYPASS		4	/* packet does not leave via dequeue;
					   (TC use only - dev_queue_xmit
					   returns this as NET_XMIT_SUCCESS) */

/* Backlog congestion levels */
#define NET_RX_SUCCESS		0   /* keep 'em coming, baby */
#define NET_RX_DROP		1  /* packet dropped */
#define NET_RX_CN_LOW		2   /* storm alert, just in case */
#define NET_RX_CN_MOD		3   /* Storm on its way! */
#define NET_RX_CN_HIGH		4   /* The storm is here */
#define NET_RX_BAD		5  /* packet dropped due to kernel error */

#define net_xmit_errno(e)	((e) != NET_XMIT_CN ? -ENOBUFS : 0)

#endif

#define MAX_ADDR_LEN	7		/* Largest hardware address length */

/*
 *	Compute the worst case header length according to the protocols
 *	used.
 */
 
#if !defined(CONFIG_AX25) && !defined(CONFIG_AX25_MODULE) && !defined(CONFIG_TR)
#define LL_MAX_HEADER	32
#else
#if defined(CONFIG_AX25) || defined(CONFIG_AX25_MODULE)
#define LL_MAX_HEADER	96
#else
#define LL_MAX_HEADER	48
#endif
#endif

#if !defined(CONFIG_NET_IPIP) && \
    !defined(CONFIG_IPV6) && !defined(CONFIG_IPV6_MODULE)
#define MAX_HEADER LL_MAX_HEADER
#else
#define MAX_HEADER (LL_MAX_HEADER + 48)
#endif

/*
 *	Network device statistics. Akin to the 2.0 ether stats but
 *	with byte counters.
 */
 
struct net_device_stats
{
	unsigned long	rx_packets;		/* total packets received	*/
	unsigned long	tx_packets;		/* total packets transmitted	*/
	unsigned long	rx_bytes;		/* total bytes received 	*/
	unsigned long	tx_bytes;		/* total bytes transmitted	*/
	unsigned long	rx_errors;		/* bad packets received		*/
	unsigned long	tx_errors;		/* packet transmit problems	*/
	unsigned long	rx_dropped;		/* no space in linux buffers	*/
	unsigned long	tx_dropped;		/* no space available in linux	*/
	unsigned long	multicast;		/* multicast packets received	*/
	unsigned long	collisions;

	/* detailed rx_errors: */
	unsigned long	rx_length_errors;
	unsigned long	rx_over_errors;		/* receiver ring buff overflow	*/
	unsigned long	rx_crc_errors;		/* recved pkt with crc error	*/
	unsigned long	rx_frame_errors;	/* recv'd frame alignment error */
	unsigned long	rx_fifo_errors;		/* recv'r fifo overrun		*/
	unsigned long	rx_missed_errors;	/* receiver missed packet	*/

	/* detailed tx_errors */
	unsigned long	tx_aborted_errors;
	unsigned long	tx_carrier_errors;
	unsigned long	tx_fifo_errors;
	unsigned long	tx_heartbeat_errors;
	unsigned long	tx_window_errors;
	
	/* for cslip etc */
	unsigned long	rx_compressed;
	unsigned long	tx_compressed;
};


/* Media selection options. */
enum {
        IF_PORT_UNKNOWN = 0,
        IF_PORT_10BASE2,
        IF_PORT_10BASET,
        IF_PORT_AUI,
        IF_PORT_100BASET,
        IF_PORT_100BASETX,
        IF_PORT_100BASEFX
};

#ifdef __KERNEL__

extern const char *if_port_text[];

#include <linux/cache.h>
#include <linux/skbuff.h>

struct neighbour;
struct neigh_parms;
struct sk_buff;

struct netif_rx_stats
{
	unsigned total;
	unsigned dropped;
	unsigned time_squeeze;
	unsigned throttled;
	unsigned fastroute_hit;
	unsigned fastroute_success;
	unsigned fastroute_defer;
	unsigned fastroute_deferred_out;
	unsigned fastroute_latency_reduction;
	unsigned cpu_collision;
} __attribute__ ((__aligned__(SMP_CACHE_BYTES)));

extern struct netif_rx_stats netdev_rx_stat[];


/*
 *	We tag multicasts with these structures.
 */
 
struct dev_mc_list
{	
	struct dev_mc_list	*next;
	__u8			dmi_addr[MAX_ADDR_LEN];
	unsigned char		dmi_addrlen;
	int			dmi_users;
	int			dmi_gusers;
};

struct hh_cache
{
	struct hh_cache *hh_next;	/* Next entry			     */
	atomic_t	hh_refcnt;	/* number of users                   */
	unsigned short  hh_type;	/* protocol identifier, f.e ETH_P_IP */
	int		hh_len;		/* length of header */
	int		(*hh_output)(struct sk_buff *skb);
	rwlock_t	hh_lock;
	/* cached hardware header; allow for machine alignment needs.        */
	unsigned long	hh_data[16/sizeof(unsigned long)];
};

/* These flag bits are private to the generic network queueing
 * layer, they may not be explicitly referenced by any other
 * code.
 */

enum netdev_state_t
{
	__LINK_STATE_XOFF=0,
	__LINK_STATE_START,
	__LINK_STATE_PRESENT,
	__LINK_STATE_SCHED,
	__LINK_STATE_NOCARRIER
};


/*
 * This structure holds at boot time configured netdevice settings. They
 * are then used in the device probing. 
 */
struct netdev_boot_setup {
	char name[IFNAMSIZ];
	struct ifmap map;
};
#define NETDEV_BOOT_SETUP_MAX 8


/*
 *	The DEVICE structure.
 *	Actually, this whole structure is a big mistake.  It mixes I/O
 *	data with strictly "high-level" data, and it has to know about
 *	almost every data structure used in the INET module.
 *
 *	FIXME: cleanup struct net_device such that network protocol info
 *	moves out.
 */

struct net_device
{

	/*
	 * This is the first field of the "visible" part of this structure
	 * (i.e. as seen by users in the "Space.c" file).  It is the name
	 * the interface.
	 */
	char			name[IFNAMSIZ];

	/*
	 *	I/O specific fields
	 *	FIXME: Merge these and struct ifmap into one
	 */
	unsigned long		rmem_end;	/* shmem "recv" end	*/
	unsigned long		rmem_start;	/* shmem "recv" start	*/
	unsigned long		mem_end;	/* shared mem end	*/
	unsigned long		mem_start;	/* shared mem start	*/
	unsigned long		base_addr;	/* device I/O address	*/
	unsigned int		irq;		/* device IRQ number	*/

	/*
	 *	Some hardware also needs these fields, but they are not
	 *	part of the usual set specified in Space.c.
	 */

	unsigned char		if_port;	/* Selectable AUI, TP,..*/
	unsigned char		dma;		/* DMA channel		*/

	unsigned long		state;

	struct net_device	*next;
	
	/* The device initialization function. Called only once. */
	int			(*init)(struct net_device *dev);

	/* ------- Fields preinitialized in Space.c finish here ------- */

	struct net_device	*next_sched;

	/* Interface index. Unique device identifier	*/
	int			ifindex;
	int			iflink;


	struct net_device_stats* (*get_stats)(struct net_device *dev);
	struct iw_statistics*	(*get_wireless_stats)(struct net_device *dev);

	/*
	 * This marks the end of the "visible" part of the structure. All
	 * fields hereafter are internal to the system, and may change at
	 * will (read: may be cleaned up at will).
	 */

	/* These may be needed for future network-power-down code. */
	unsigned long		trans_start;	/* Time (in jiffies) of last Tx	*/
	unsigned long		last_rx;	/* Time of last Rx	*/

	unsigned short		flags;	/* interface flags (a la BSD)	*/
	unsigned short		gflags;
	unsigned		mtu;	/* interface MTU value		*/
	unsigned short		type;	/* interface hardware type	*/
	unsigned short		hard_header_len;	/* hardware hdr length	*/
	void			*priv;	/* pointer to private data	*/

	struct net_device	*master; /* Pointer to master device of a group,
					  * which this device is member of.
					  */

	/* Interface address info. */
	unsigned char		broadcast[MAX_ADDR_LEN];	/* hw bcast add	*/
	unsigned char		pad;		/* make dev_addr aligned to 8 bytes */
	unsigned char		dev_addr[MAX_ADDR_LEN];	/* hw address	*/
	unsigned char		addr_len;	/* hardware address length	*/

	struct dev_mc_list	*mc_list;	/* Multicast mac addresses	*/
	int			mc_count;	/* Number of installed mcasts	*/
	int			promiscuity;
	int			allmulti;

	int			watchdog_timeo;
	struct timer_list	watchdog_timer;

	/* Protocol specific pointers */
	
	void 			*atalk_ptr;	/* AppleTalk link 	*/
	void			*ip_ptr;	/* IPv4 specific data	*/  
	void                    *dn_ptr;        /* DECnet specific data */
	void                    *ip6_ptr;       /* IPv6 specific data */
	void			*ec_ptr;	/* Econet specific data	*/

	struct Qdisc		*qdisc;
	struct Qdisc		*qdisc_sleeping;
	struct Qdisc		*qdisc_list;
	struct Qdisc		*qdisc_ingress;
	unsigned long		tx_queue_len;	/* Max frames per queue allowed */

	/* hard_start_xmit synchronizer */
	spinlock_t		xmit_lock;
	/* cpu id of processor entered to hard_start_xmit or -1,
	   if nobody entered there.
	 */
	int			xmit_lock_owner;
	/* device queue lock */
	spinlock_t		queue_lock;
	/* Number of references to this device */
	atomic_t		refcnt;
	/* The flag marking that device is unregistered, but held by an user */