Linux核心数据结构--device

系统中每个网络设备都用一个设备数据结构来表示。

struct 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;


  /* I/O specific fields                                           */

  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 char           irq;             /* device IRQ number    */



  /* Low-level status flags. */

  volatile unsigned char  start,           /* start an operation   */

                          interrupt;       /* interrupt arrived    */

  unsigned long           tbusy;           /* transmitter busy     */

  struct device           *next;



  /* The device initialization function. Called only once.         */

int                     (*init)(struct device *dev);



  /* 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          */



  struct enet_statistics* (*get_stats)(struct 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 (jiffies) of

                                              last transmit        */

  unsigned long           last_rx;         /* Time of last Rx      */

unsigned short          flags;           /* interface flags (BSD)*/

  unsigned short          family;          /* address family ID    */

  unsigned short          metric;          /* routing metric       */

  unsigned short          mtu;             /* MTU value            */

  unsigned short          type;            /* hardware type        */

  unsigned short          hard_header_len; /* hardware hdr len     */

  void                    *priv;           /* private data         */



  /* Interface address info. */

  unsigned char           broadcast[MAX_ADDR_LEN];

  unsigned char           pad;              

  unsigned char           dev_addr[MAX_ADDR_LEN]; 
  unsigned char           addr_len;        /* hardware addr len    */

  unsigned long           pa_addr;         /* protocol address     */

  unsigned long           pa_brdaddr;      /* protocol broadcast addr*/

  unsigned long           pa_dstaddr;      /* protocol P-P other addr*/

  unsigned long           pa_mask;         /* protocol netmask     */

  unsigned short          pa_alen;         /* protocol address len */



  struct dev_mc_list      *mc_list;        /* M'cast mac addrs     */

  int                     mc_count;        /* No installed mcasts  */

 

  struct ip_mc_list       *ip_mc_list;     /* IP m'cast filter chain */

  __u32                   tx_queue_len;    /* Max frames per queue   */

   

  /* For load balancing driver pair support */

  unsigned long           pkt_queue;       /* Packets queued       */

  struct device           *slave;          /* Slave device         */

  struct net_alias_info   *alias_info;     /* main dev alias info  */

  struct net_alias        *my_alias;       /* alias devs           */

 

  /* Pointer to the interface buffers. */

  struct sk_buff_head     buffs[DEV_NUMBUFFS];


  /* Pointers to interface service routines. */

  int                     (*open)(struct device *dev);

  int                     (*stop)(struct device *dev);

  int                     (*hard_start_xmit) (struct sk_buff *skb,

                                              struct device *dev);

  int                     (*hard_header) (struct sk_buff *skb,

                                          struct device *dev,

                                          unsigned short type,

                                          void *daddr,

                                          void *saddr,

                                          unsigned len);

  int                     (*rebuild_header)(void *eth,

                                          struct device *dev,

                                          unsigned long raddr,

                                          struct sk_buff *skb);

  void                    (*set_multicast_list)(struct device *dev);

  int                     (*set_mac_address)(struct device *dev,

                                          void *addr);

  int                     (*do_ioctl)(struct device *dev,

                                          struct ifreq *ifr,

                                          int cmd);

  int                     (*set_config)(struct device *dev,

                                          struct ifmap *map);

  void                    (*header_cache_bind)(struct hh_cache **hhp,

                                          struct device *dev,

                                          unsigned short htype,

                                          __u32 daddr);

  void                    (*header_cache_update)(struct hh_cache *hh,

                                          struct device *dev,

                                          unsigned char *  haddr);

  int                     (*change_mtu)(struct device *dev,

                                          int new_mtu);

  struct iw_statistics*   (*get_wireless_stats)(struct device *dev);

};