#ifndef	_DEVBLKDEV_H#define _DEVBLKDEV_H#include <dev/lib/root.h>#include <kern/sched.h>#include "req.h"#define SECTSIZE 512#define SECTBITS 9#define MAXBUFPERIO 32struct buf_t;struct blkdev_t {	sema_t reqsema;	reqq_t reqq; /* requeset queue */	req_t * curreq; /* current request */	blkdev_t() : reqsema(MAXBUFPERIO * 2) { curreq = NULL; }	virtual ~blkdev_t();	void addreq(int rw, buf_t * b);	void doreq(req_t * r);	void doreq();	void endcurreq();	virtual void docurreq() = 0;	virtual int open(int flags, inode_t * inode, fdes_t ** fdes);	virtual int ioctl(dev_t dev, int cmd, ulong arg) = 0;	virtual ulong getsize(dev_t dev) = 0;};	extern blkdev_t * blkdevvec[MAXBLKDEV];extern inline blkdev_t * getblkdev(dev_t dev){	return (major(dev) < MAXBLKDEV) ?  blkdevvec[major(dev)] : NULL;}struct inode_t;struct fdes_t;extern int openblkfd(int flags, inode_t * inode, fdes_t ** fdes);#endif