bc_dev.h

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/*******************************************************************
 *	Copyright (c) 1994-1998 Jetico, Inc., Finland
 *	All rights reserved.
 *
 *	File:		driver/bc.h
 *
 *	Description:	device structure
 *
 *	Scope:		BestCrypt pseudo-device driver
 *
 *	Platforms:	Linux
 *
 *	Author:		Nail R. Kaipov
 *
 *	Created:	10-Nov-1998
 *
 *	Revision:	21-Mar-2000.	cleaning up (v0.4b-2)
 *			07-Feb-2001.	unified for 2.2.x & 2.4.x
 *
 *******************************************************************/

#ifndef __BC__
#define __BC__

#ifdef __KERNEL__

/* bc device description */
struct bc_device {
	int			bc_number;	/* number of device  */
	int			bc_refcnt;	/* references count  */
	loff_t			bc_offset;	/* master offset     */

	loff_t			bc_start_sector;/* starting sector   */
	loff_t			bc_num_sectors;	/* data	size         */

	KEY_HANDLE		bc_key;		/* key handle        */
	struct bc_algorithm	*bc_alg;	/* encryption algo   */
	struct file		*bc_file;	/* mounted container */
	struct dentry		*bc_dentry;	/* bc special dentry */
	struct semaphore	bc_control;	/* ioctl control     */
	int			bc_activity;	/* monitor disk r/w  */

#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,0) && LINUX_VERSION_CODE <= KERNEL_VERSION(2,7,0))
	dev_t			bc_dev;		/* real device       */
	atomic_t		bc_pending;	/* # of pending bios	*/
	spinlock_t		bc_lock;	/* bc access lock	*/
	struct semaphore	bc_thread;	/* start/stop thread	*/
	struct semaphore	bc_run;		/* worker thread signal	*/
	unsigned char		*bc_buffer;	/* buffer for write op	*/

	struct gendisk		*bc_gendisk;	/* underlying gendisk	*/
	int			bc_gfpmask;	/* save inode GFP mask	*/
	struct bio		*bc_biohead;	/* pending request bios	*/
	struct bio		*bc_biotail;	/* pending request bios	*/
	request_queue_t		bc_queue;	/* per-device req queue	*/

	int			(*bc_process_bio)(struct bc_device *bc, struct bio *bio);
#elif (LINUX_VERSION_CODE >= KERNEL_VERSION(2,4,0) && LINUX_VERSION_CODE <= KERNEL_VERSION(2,5,0))
	kdev_t			bc_dev;		/* real device       */
	atomic_t		bc_pending;	/* number of pending */
	spinlock_t		bc_lock;	/* bc access lock    */
	devfs_handle_t		bc_hdevfs;	/* dev devfs handle  */
	struct semaphore	bc_thread;	/* start/stop thread */
	struct semaphore	bc_run;		/* thread workload   */
	struct buffer_head	*bc_bh;		/* buffer list head  */
	struct buffer_head	*bc_bhtail;	/* buffer list tail  */
	unsigned char		*bc_buffer;	/* write buffer      */
	int			bc_gfpmask;
#else
	kdev_t			bc_dev;		/* real device       */
#endif
	struct file_operations	bc_fops;
	struct file_operations  *bc_save_fops;
	struct bc_device_flags {
		unsigned	active     : 1; /* serves requests    */
		unsigned	busy       : 1; /* rescan in progress */
		unsigned	readonly   : 1; /* read only          */
		unsigned	multpart   : 1; /* partition check    */
		unsigned	iv_64bit   : 1; /* full 64-bit IV     */
		unsigned	mounted    : 1; /* 2.6 mounted&locked */
		unsigned	configured : 1; /* 2.6 configured     */
		unsigned	reserved   : 25;
	}			 bc_flags;
};

struct bc_disk {
	int			bd_number;	/* disk number = real minor  */
	int			bd_refcnt;	/* references count          */
	loff_t			bd_offset;	/* disk offset               */
	struct bc_disk_flags {
		unsigned	configured : 1;	/* disk configured           */
		unsigned	mounted    : 1; /* device mounted and locked */
		unsigned	reserved   : 30;
	}			bd_flags;
};

#define DEVICE_CONF	"bc.conf"
#define DEVICE_STAT	"bc.stat"


#define DEFAULT_BC_DEVICES	16
#define DEFAULT_BC_PARTITIONS	1
#define MAX_MINORS		256

#if   ((LINUX_VERSION_CODE >= KERNEL_VERSION(2,2,0)) && (LINUX_VERSION_CODE < KERNEL_VERSION(2,3,37)))

#define MAJOR_NR	0x07
#define DEVICE_NAME	"loop"
extern struct file_operations *get_blkfops(int);
#define BC_BUFFERS	NR_REQUEST/4
#define BC_BUFFER_SIZE	4096

#elif ((LINUX_VERSION_CODE >= KERNEL_VERSION(2,4,2)) && (LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0)))

#define MAJOR_NR	0xBC
#define DEVICE_NAME	"bcrypt"
#define BC_BUFFER_SIZE	4096

#elif ((LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,0)) && (LINUX_VERSION_CODE < KERNEL_VERSION(2,7,0)))
#define MAJOR_NR	0xBC
#define DEVICE_NAME	"bcrypt"
#define BC_BUFFER_SIZE	PAGE_SIZE

#else
#error BestCrypt should not work on this kernel
#endif

#define BC_HANDLER(dbg, x, y)   case (x): /*printk(dbg "\n"); */\
				error = (y); \
				break;

#define BC_GET_ARG(arg, query)  if (NULL == (arg)) return -EINVAL; \
                                if (copy_from_user(&(query), arg, sizeof(query))) \
					return -EFAULT;
									

#endif /* __KERNEL__ */

#endif /* __BC__ */