[linux-2.6-block.git] / include / asm-mips / ioctl.h

/*
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * Copyright (C) 1995, 96, 99, 2001 Ralf Baechle
 */
#ifndef _ASM_IOCTL_H
#define _ASM_IOCTL_H

/*
 * The original linux ioctl numbering scheme was just a general
 * "anything goes" setup, where more or less random numbers were
 * assigned.  Sorry, I was clueless when I started out on this.
 *
 * On the alpha, we'll try to clean it up a bit, using a more sane
 * ioctl numbering, and also trying to be compatible with OSF/1 in
 * the process. I'd like to clean it up for the i386 as well, but
 * it's so painful recognizing both the new and the old numbers..
 *
 * The same applies for for the MIPS ABI; in fact even the macros
 * from Linux/Alpha fit almost perfectly.
 */

#define _IOC_NRBITS	8
#define _IOC_TYPEBITS	8
#define _IOC_SIZEBITS	13
#define _IOC_DIRBITS	3

#define _IOC_NRMASK	((1 << _IOC_NRBITS)-1)
#define _IOC_TYPEMASK	((1 << _IOC_TYPEBITS)-1)
#define _IOC_SIZEMASK	((1 << _IOC_SIZEBITS)-1)
#define _IOC_DIRMASK	((1 << _IOC_DIRBITS)-1)

#define _IOC_NRSHIFT	0
#define _IOC_TYPESHIFT	(_IOC_NRSHIFT+_IOC_NRBITS)
#define _IOC_SIZESHIFT	(_IOC_TYPESHIFT+_IOC_TYPEBITS)
#define _IOC_DIRSHIFT	(_IOC_SIZESHIFT+_IOC_SIZEBITS)

/*
 * Direction bits _IOC_NONE could be 0, but OSF/1 gives it a bit.
 * And this turns out useful to catch old ioctl numbers in header
 * files for us.
 */
#define _IOC_NONE	1U
#define _IOC_READ	2U
#define _IOC_WRITE	4U

/*
 * The following are included for compatibility
 */
#define _IOC_VOID	0x20000000
#define _IOC_OUT	0x40000000
#define _IOC_IN		0x80000000
#define _IOC_INOUT	(IOC_IN|IOC_OUT)

#define _IOC(dir, type, nr, size) \
	(((dir)  << _IOC_DIRSHIFT) | \
	 ((type) << _IOC_TYPESHIFT) | \
	 ((nr)   << _IOC_NRSHIFT) | \
	 ((size) << _IOC_SIZESHIFT))

/* provoke compile error for invalid uses of size argument */
extern unsigned int __invalid_size_argument_for_IOC;
#define _IOC_TYPECHECK(t) \
	((sizeof(t) == sizeof(t[1]) && \
	  sizeof(t) < (1 << _IOC_SIZEBITS)) ? \
	  sizeof(t) : __invalid_size_argument_for_IOC)

/* used to create numbers */
#define _IO(type, nr)		_IOC(_IOC_NONE, (type), (nr), 0)
#define _IOR(type, nr, size)	_IOC(_IOC_READ, (type), (nr), (_IOC_TYPECHECK(size)))
#define _IOW(type, nr, size)	_IOC(_IOC_WRITE, (type), (nr), (_IOC_TYPECHECK(size)))
#define _IOWR(type, nr, size)	_IOC(_IOC_READ|_IOC_WRITE, (type), (nr), (_IOC_TYPECHECK(size)))
#define _IOR_BAD(type, nr, size)	_IOC(_IOC_READ, (type), (nr), sizeof(size))
#define _IOW_BAD(type, nr, size)	_IOC(_IOC_WRITE, (type), (nr), sizeof(size))
#define _IOWR_BAD(type, nr, size)	_IOC(_IOC_READ|_IOC_WRITE, (type), (nr), sizeof(size))


/* used to decode them.. */
#define _IOC_DIR(nr)		(((nr) >> _IOC_DIRSHIFT) & _IOC_DIRMASK)
#define _IOC_TYPE(nr)		(((nr) >> _IOC_TYPESHIFT) & _IOC_TYPEMASK)
#define _IOC_NR(nr)		(((nr) >> _IOC_NRSHIFT) & _IOC_NRMASK)
#define _IOC_SIZE(nr)		(((nr) >> _IOC_SIZESHIFT) & _IOC_SIZEMASK)

/* ...and for the drivers/sound files... */

#define IOC_IN		(_IOC_WRITE << _IOC_DIRSHIFT)
#define IOC_OUT		(_IOC_READ << _IOC_DIRSHIFT)
#define IOC_INOUT	((_IOC_WRITE|_IOC_READ) << _IOC_DIRSHIFT)
#define IOCSIZE_MASK	(_IOC_SIZEMASK << _IOC_SIZESHIFT)
#define IOCSIZE_SHIFT	(_IOC_SIZESHIFT)

#endif /* _ASM_IOCTL_H */
Commit	Line	Data
1da177e4 LT	1	/*
	2	* This file is subject to the terms and conditions of the GNU General Public
	3	* License. See the file "COPYING" in the main directory of this archive
	4	* for more details.
	5	*
	6	* Copyright (C) 1995, 96, 99, 2001 Ralf Baechle
	7	*/
	8	#ifndef _ASM_IOCTL_H
	9	#define _ASM_IOCTL_H
	10
	11	/*
	12	* The original linux ioctl numbering scheme was just a general
	13	* "anything goes" setup, where more or less random numbers were
	14	* assigned. Sorry, I was clueless when I started out on this.
	15	*
	16	* On the alpha, we'll try to clean it up a bit, using a more sane
	17	* ioctl numbering, and also trying to be compatible with OSF/1 in
	18	* the process. I'd like to clean it up for the i386 as well, but
	19	* it's so painful recognizing both the new and the old numbers..
	20	*
	21	* The same applies for for the MIPS ABI; in fact even the macros
	22	* from Linux/Alpha fit almost perfectly.
	23	*/
	24
	25	#define _IOC_NRBITS 8
	26	#define _IOC_TYPEBITS 8
	27	#define _IOC_SIZEBITS 13
	28	#define _IOC_DIRBITS 3
	29
	30	#define _IOC_NRMASK ((1 << _IOC_NRBITS)-1)
	31	#define _IOC_TYPEMASK ((1 << _IOC_TYPEBITS)-1)
	32	#define _IOC_SIZEMASK ((1 << _IOC_SIZEBITS)-1)
	33	#define _IOC_DIRMASK ((1 << _IOC_DIRBITS)-1)
	34
	35	#define _IOC_NRSHIFT 0
	36	#define _IOC_TYPESHIFT (_IOC_NRSHIFT+_IOC_NRBITS)
	37	#define _IOC_SIZESHIFT (_IOC_TYPESHIFT+_IOC_TYPEBITS)
	38	#define _IOC_DIRSHIFT (_IOC_SIZESHIFT+_IOC_SIZEBITS)
	39
1da177e4 LT	40	/*
	41	* Direction bits _IOC_NONE could be 0, but OSF/1 gives it a bit.
	42	* And this turns out useful to catch old ioctl numbers in header
	43	* files for us.
	44	*/
	45	#define _IOC_NONE 1U
	46	#define _IOC_READ 2U
	47	#define _IOC_WRITE 4U
	48
	49	/*
	50	* The following are included for compatibility
	51	*/
	52	#define _IOC_VOID 0x20000000
	53	#define _IOC_OUT 0x40000000
	54	#define _IOC_IN 0x80000000
	55	#define _IOC_INOUT (IOC_IN\|IOC_OUT)
	56
21a151d8	57	#define _IOC(dir, type, nr, size) \
1da177e4 LT	58	(((dir) << _IOC_DIRSHIFT) \| \
	59	((type) << _IOC_TYPESHIFT) \| \
	60	((nr) << _IOC_NRSHIFT) \| \
	61	((size) << _IOC_SIZESHIFT))
	62
	63	/* provoke compile error for invalid uses of size argument */
	64	extern unsigned int __invalid_size_argument_for_IOC;
	65	#define _IOC_TYPECHECK(t) \
	66	((sizeof(t) == sizeof(t[1]) && \
	67	sizeof(t) < (1 << _IOC_SIZEBITS)) ? \
	68	sizeof(t) : __invalid_size_argument_for_IOC)
	69
	70	/* used to create numbers */
21a151d8 RB	71	#define _IO(type, nr) _IOC(_IOC_NONE, (type), (nr), 0)
	72	#define _IOR(type, nr, size) _IOC(_IOC_READ, (type), (nr), (_IOC_TYPECHECK(size)))
	73	#define _IOW(type, nr, size) _IOC(_IOC_WRITE, (type), (nr), (_IOC_TYPECHECK(size)))
	74	#define _IOWR(type, nr, size) _IOC(_IOC_READ\|_IOC_WRITE, (type), (nr), (_IOC_TYPECHECK(size)))
	75	#define _IOR_BAD(type, nr, size) _IOC(_IOC_READ, (type), (nr), sizeof(size))
	76	#define _IOW_BAD(type, nr, size) _IOC(_IOC_WRITE, (type), (nr), sizeof(size))
	77	#define _IOWR_BAD(type, nr, size) _IOC(_IOC_READ\|_IOC_WRITE, (type), (nr), sizeof(size))
1da177e4 LT	78
	79
	80	/* used to decode them.. */
	81	#define _IOC_DIR(nr) (((nr) >> _IOC_DIRSHIFT) & _IOC_DIRMASK)
	82	#define _IOC_TYPE(nr) (((nr) >> _IOC_TYPESHIFT) & _IOC_TYPEMASK)
	83	#define _IOC_NR(nr) (((nr) >> _IOC_NRSHIFT) & _IOC_NRMASK)
	84	#define _IOC_SIZE(nr) (((nr) >> _IOC_SIZESHIFT) & _IOC_SIZEMASK)
	85
	86	/* ...and for the drivers/sound files... */
	87
	88	#define IOC_IN (_IOC_WRITE << _IOC_DIRSHIFT)
	89	#define IOC_OUT (_IOC_READ << _IOC_DIRSHIFT)
	90	#define IOC_INOUT ((_IOC_WRITE\|_IOC_READ) << _IOC_DIRSHIFT)
	91	#define IOCSIZE_MASK (_IOC_SIZEMASK << _IOC_SIZESHIFT)
	92	#define IOCSIZE_SHIFT (_IOC_SIZESHIFT)
	93
	94	#endif /* _ASM_IOCTL_H */