freebsd-skq/sys/kern/kern_conf.c
phk 507c870974 Make a "DWIM" function for adding [bc]devsw entries for bdev drivers.
Saves about 280 butes of source per driver, 56 bytes in object size
and another 56 bytes moves from data to bss.

No functional change intended nor expected.

GENERIC should be about one k smaller now :-)
1996-07-23 21:52:43 +00:00

194 lines
5.0 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 1.9 1995/12/22 15:56:33 phk 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)
void
cdevsw_make(struct bdevsw *from)
{
struct cdevsw *to = from->d_cdev;
if (!to)
panic("No target cdevsw in bdevsw");
to->d_open = from->d_open;
to->d_close = from->d_close;
to->d_read = rawread;
to->d_write = rawwrite;
to->d_ioctl = from->d_ioctl;
to->d_stop = nostop;
to->d_reset = nullreset;
to->d_devtotty = nodevtotty;
to->d_select = seltrue;
to->d_mmap = nommap;
to->d_strategy = from->d_strategy;
to->d_name = from->d_name;
to->d_bdev = from;
to->d_maj = -1;
}
void
bdevsw_add_generic(int bdev, int cdev, struct bdevsw *bdevsw)
{
dev_t dev;
cdevsw_make(bdevsw);
dev = makedev(cdev, 0);
cdevsw_add(&dev, bdevsw->d_cdev, NULL);
dev = makedev(bdev, 0);
bdevsw_add(&dev, bdevsw , NULL);
}