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/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
/* All Rights Reserved */
/*
* Copyright 2009 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*
* Copyright 2017 Nexenta Systems, Inc. All rights reserved.
*/
/*
* UNIX Device Driver Interface functions
* (excerpts)
*/
#include <sys/types.h>
#include <sys/sysmacros.h>
#include <sys/param.h>
#include <sys/ddi.h>
#include <sys/mkdev.h>
#include <sys/debug.h>
#ifndef NODEV32
#define NODEV32 (dev32_t)(-1)
#endif /* NODEV32 */
/*
* return internal major number corresponding to device
* number (new format) argument
*/
major_t
getmajor(dev_t dev)
{
#ifdef _LP64
return ((major_t)((dev >> NBITSMINOR64) & MAXMAJ64));
#else
return ((major_t)((dev >> NBITSMINOR) & MAXMAJ));
#endif
}
/*
* return internal minor number corresponding to device
* number (new format) argument
*/
minor_t
getminor(dev_t dev)
{
#ifdef _LP64
return ((minor_t)(dev & MAXMIN64));
#else
return ((minor_t)(dev & MAXMIN));
#endif
}
/*
* encode external major and minor number arguments into a
* new format device number
*/
dev_t
makedevice(major_t maj, minor_t minor)
{
#ifdef _LP64
return (((dev_t)maj << NBITSMINOR64) | (minor & MAXMIN64));
#else
return (((dev_t)maj << NBITSMINOR) | (minor & MAXMIN));
#endif
}
/*
* Compress 'long' device number encoding to 32-bit device number
* encoding. If it won't fit, we return failure, but set the
* device number to 32-bit NODEV for the sake of our callers.
*/
int
cmpldev(dev32_t *dst, dev_t dev)
{
#if defined(_LP64)
if (dev == NODEV) {
*dst = NODEV32;
} else {
major_t major = dev >> L_BITSMINOR;
minor_t minor = dev & L_MAXMIN;
if (major > L_MAXMAJ32 || minor > L_MAXMIN32) {
*dst = NODEV32;
return (0);
}
*dst = (dev32_t)((major << L_BITSMINOR32) | minor);
}
#else
*dst = (dev32_t)dev;
#endif
return (1);
}
/*
* Expand 32-bit dev_t's to long dev_t's. Expansion always "fits"
* into the return type, but we're careful to expand NODEV explicitly.
*/
dev_t
expldev(dev32_t dev32)
{
#ifdef _LP64
if (dev32 == NODEV32)
return (NODEV);
return (makedevice((dev32 >> L_BITSMINOR32) & L_MAXMAJ32,
dev32 & L_MAXMIN32));
#else
return ((dev_t)dev32);
#endif
}
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