79c0c4b77f
vfs_cache.c: Fix a very rare probelm in the vnode-cache. Submitted by: Terry Lambert <terry@lambert.org>
160 lines
4.3 KiB
C
160 lines
4.3 KiB
C
/*-
|
|
* 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 1.8 1995/12/21 20:09:39 julian Exp $
|
|
*/
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/types.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/conf.h>
|
|
#include <sys/vnode.h>
|
|
|
|
#define NUMCDEV 96
|
|
#define NUMBDEV 32
|
|
|
|
struct bdevsw *bdevsw[NUMBDEV];
|
|
int nblkdev = NUMBDEV;
|
|
struct cdevsw *cdevsw[NUMCDEV];
|
|
int nchrdev = NUMCDEV;
|
|
|
|
|
|
|
|
/*
|
|
* Routine to determine if a device is a disk.
|
|
*
|
|
* KLUDGE XXX add flags to cdevsw entries for disks XXX
|
|
* A minimal stub routine can always return 0.
|
|
*/
|
|
int
|
|
isdisk(dev, type)
|
|
dev_t dev;
|
|
int type;
|
|
{
|
|
|
|
switch (major(dev)) {
|
|
case 15: /* VBLK: vn, VCHR: cd */
|
|
return (1);
|
|
case 0: /* wd */
|
|
case 2: /* fd */
|
|
case 4: /* sd */
|
|
case 6: /* cd */
|
|
case 7: /* mcd */
|
|
case 16: /* scd */
|
|
case 17: /* matcd */
|
|
case 18: /* ata */
|
|
case 19: /* wcd */
|
|
case 20: /* od */
|
|
if (type == VBLK)
|
|
return (1);
|
|
return (0);
|
|
case 3: /* wd */
|
|
case 9: /* fd */
|
|
case 13: /* sd */
|
|
case 29: /* mcd */
|
|
case 43: /* vn */
|
|
case 45: /* scd */
|
|
case 46: /* matcd */
|
|
case 69: /* wcd */
|
|
case 70: /* od */
|
|
if (type == VCHR)
|
|
return (1);
|
|
/* fall through */
|
|
default:
|
|
return (0);
|
|
}
|
|
/* NOTREACHED */
|
|
}
|
|
|
|
|
|
/*
|
|
* Routine to convert from character to block device number.
|
|
*
|
|
* A minimal stub routine can always return NODEV.
|
|
*/
|
|
dev_t
|
|
chrtoblk(dev_t dev)
|
|
{
|
|
struct bdevsw *bd;
|
|
struct cdevsw *cd;
|
|
|
|
if(cd = cdevsw[major(dev)]) {
|
|
if ( (bd = cd->d_bdev) )
|
|
return(makedev(bd->d_maj,minor(dev)));
|
|
}
|
|
return(NODEV);
|
|
}
|
|
|
|
/*
|
|
* (re)place an entry in the bdevsw or cdevsw table
|
|
* return the slot used in major(*descrip)
|
|
*/
|
|
#define ADDENTRY(TTYPE,NXXXDEV) \
|
|
int TTYPE##_add(dev_t *descrip, \
|
|
struct TTYPE *newentry, \
|
|
struct TTYPE **oldentry) \
|
|
{ \
|
|
int i ; \
|
|
if ( (int)*descrip == -1) { /* auto (0 is valid) */ \
|
|
/* \
|
|
* Search the table looking for a slot... \
|
|
*/ \
|
|
for (i = 0; i < NXXXDEV; i++) \
|
|
if (TTYPE[i] == NULL) \
|
|
break; /* found one! */ \
|
|
/* out of allocable slots? */ \
|
|
if (i == NXXXDEV) { \
|
|
return ENFILE; \
|
|
} \
|
|
} else { /* assign */ \
|
|
i = major(*descrip); \
|
|
if (i < 0 || i >= NXXXDEV) { \
|
|
return EINVAL; \
|
|
} \
|
|
} \
|
|
\
|
|
/* maybe save old */ \
|
|
if (oldentry) { \
|
|
*oldentry = TTYPE[i]; \
|
|
} \
|
|
newentry->d_maj = i; \
|
|
/* replace with new */ \
|
|
TTYPE[i] = newentry; \
|
|
\
|
|
/* done! let them know where we put it */ \
|
|
*descrip = makedev(i,0); \
|
|
return 0; \
|
|
} \
|
|
|
|
ADDENTRY(bdevsw, nblkdev)
|
|
ADDENTRY(cdevsw, nchrdev)
|