cs350/kern/include/device.h

/*
 * Copyright (c) 2000, 2001, 2002, 2003, 2004, 2005, 2008, 2009
 *	The President and Fellows of Harvard College.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE UNIVERSITY AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE UNIVERSITY OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#ifndef _DEVICE_H_
#define _DEVICE_H_

/*
 * Devices.
 */


struct uio;  /* in <uio.h> */

/*
 * Filesystem-namespace-accessible device.
 * d_io is for both reads and writes; the uio indicates the direction.
 */
struct device {
	int (*d_open)(struct device *, int flags_from_open);
	int (*d_close)(struct device *);
	int (*d_io)(struct device *, struct uio *);
	int (*d_ioctl)(struct device *, int op, userptr_t data);

	blkcnt_t d_blocks;
	blksize_t d_blocksize;

	dev_t d_devnumber;	/* serial number for this device */

	void *d_data;		/* device-specific data */
};

/* Create vnode for a vfs-level device. */
struct vnode *dev_create_vnode(struct device *dev);


/* Initialization functions for builtin vfs-level devices. */
void devnull_create(void);

/* Function that kicks off device probe and attach. */
void dev_bootstrap(void);


#endif /* _DEVICE_H_ */