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/*-
* Parts Copyright (c) 1995 Terrence R. Lambert
* Copyright (c) 1995 Julian R. Elischer
* All rights reserved.
*
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Terrence R. Lambert.
* 4. The name Terrence R. Lambert may not be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY Julian R. Elischer ``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 TERRENCE R. LAMBERT 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.
*
* $Id: kern_conf.c,v 1.31 1999/03/23 21:11:47 dfr Exp $
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/module.h>
#include <sys/conf.h>
#include <sys/vnode.h>
#define NUMCDEV 256
#define cdevsw_ALLOCSTART (NUMCDEV/2)
struct cdevsw *cdevsw[NUMCDEV];
int nchrdev = NUMCDEV;
int bmaj2cmaj[NUMCDEV];
int nblkdev = NUMCDEV;
/*
* Routine to convert from character to block device number.
*
* A minimal stub routine can always return NODEV.
*/
dev_t
chrtoblk(dev_t dev)
{
struct cdevsw *cd;
if((cd = cdevsw[major(dev)]) != NULL) {
if (cd->d_bmaj != -1)
return(makedev(cd->d_bmaj,minor(dev)));
}
return(NODEV);
}
int
cdevsw_add(dev_t *descrip,
struct cdevsw *newentry,
struct cdevsw **oldentry)
{
int i ;
if ( (int)*descrip == NODEV) { /* auto (0 is valid) */
/*
* Search the table looking for a slot...
*/
for (i = cdevsw_ALLOCSTART; i < nchrdev; i++)
if (cdevsw[i] == NULL)
break; /* found one! */
/* out of allocable slots? */
if (i >= nchrdev) {
return ENFILE;
}
} else { /* assign */
i = major(*descrip);
if (i < 0 || i >= nchrdev) {
return EINVAL;
}
}
/* maybe save old */
if (oldentry) {
*oldentry = cdevsw[i];
}
if (newentry) {
newentry->d_bmaj = -1;
newentry->d_maj = i;
}
/* replace with new */
cdevsw[i] = newentry;
/* done! let them know where we put it */
*descrip = makedev(i,0);
return 0;
}
/*
* note must call cdevsw_add before bdevsw_add due to d_bmaj hack.
*/
void
cdevsw_add_generic(int bmaj, int cmaj, struct cdevsw *cdevsw)
{
dev_t dev;
dev = makedev(cmaj, 0);
cdevsw_add(&dev, cdevsw, NULL);
bmaj2cmaj[bmaj] = cmaj;
}
int
devsw_module_handler(module_t mod, int what, void* arg)
{
struct devsw_module_data* data = (struct devsw_module_data*) arg;
int error;
switch (what) {
case MOD_LOAD:
error = cdevsw_add(&data->cdev, data->cdevsw, NULL);
if (!error && data->cdevsw->d_strategy != nostrategy) {
if (data->bdev == NODEV)
data->bdev = data->cdev;
bmaj2cmaj[major(data->bdev)] = major(data->cdev);
}
if (!error && data->chainevh)
error = data->chainevh(mod, what, data->chainarg);
return error;
case MOD_UNLOAD:
if (data->chainevh) {
error = data->chainevh(mod, what, data->chainarg);
if (error)
return error;
}
if (data->cdevsw->d_strategy != nostrategy)
bmaj2cmaj[major(data->bdev)] = 0;
error = cdevsw_add(&data->cdev, NULL, NULL);
return error;
}
if (data->chainevh)
return data->chainevh(mod, what, data->chainarg);
else
return 0;
}
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