rawtx.h

实现一个网卡到内存空间的零拷贝程序

/*
 *  rawtx.h
 *  Joris van Rantwijk, May 2001.
 *
 *  Desperate attempt to implement a quick-and-dirty zero-copy
 *  networking interface in the Linux kernel.
 */

#include <linux/types.h>
#include <linux/unistd.h>
#include <asm/atomic.h>

#define RAWTX_MAJOR		241

#define RAWTX_DBUFFER_MAX_SIZE	65536
#define RAWTX_BUFFER_TAIL_ROOM	(sizeof(struct skb_shared_info))
#define RAWTX_UDP_IP_HEADER_LEN	(20 + 8)

#define RAWTX_IOCTL_SETDEVICE   1
#define RAWTX_IOCTL_SETPROTO	2
#define RAWTX_IOCTL_SETSADDR    3
#define RAWTX_IOCTL_SETDADDR    4
#define RAWTX_IOCTL_SETSRCADDR	5
#define RAWTX_IOCTL_SETDSTADDR	6
#define RAWTX_IOCTL_SETQUEUELEN 7
#define RAWTX_IOCTL_SENDBUFFER	8

#define RAWTX_PROTO_RAW		1
#define RAWTX_PROTO_ETHERNET	2
#define RAWTX_PROTO_UDPIP	3
#define RAWTX_PROTO_UDPIP_NOSUM 4

struct rawtx_private_data;

struct rawtx_buffer {
	volatile int busy;
	unsigned int header_len;
	unsigned int data_len;
	char buffer[0];
};

/* end */